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The removal of necrotic and vital pulp substrates and microorganisms and their toxins from the root canal system (RCS) has been found to be the basis for a successful endodontic treatment. In this study, our aim was to evaluate the effect of passive ultrasonic irrigation (PUI) on the elimination of the organic remnant tissue from infected, narrow and curved mandibular root canals during their instrumentation. For this purpose, mesiobuccal canals from mandibular first molars were instrumented with the RaCe rotary system, using PUI activation or conventional irrigation (CI) and two apical diameters (#25 and #35). The root canal cleanness of the samples was evaluated by microscopy and using a modified Langeland’s ordinal scale. Parametric and non-parametric statistical analyses and principal coordinates analysis (PCoA) of the samples were performed. When PUI was used, there was a significant reduction of the organic remnant in the apical enlargement of 25 at 2 mm from the apex (p &lt, 0.001). After pooling the groups, regardless of the depth of the observation (2 and 4 mm from the apex), the pair #35 + PUI vs. #25 + CI showed statistically significant differences (p &lt, 0.001). The effect of PUI explained 65% of the overall variance when compared with the CI samples. The use of PUI reduced the organic material of narrow infected and curved root canals with an apical enlargement of #25 and #35. When PUI is not used, a biomechanical instrumentation up to a diameter ≥#35 is recommended.

This research is part of a broader investigation to analyse the processes followed by the Caguas Municipality at the Commonwealth of Puerto Rico in an effort to develop the characteristics of a ‘Smart City’ as an example of sustainable development. We describe the integration of the educational institutions’ initiatives and the municipal government strategic plan to contribute to the knowledge and intellectual capital that brings sustainability to the city. An actor's model was designed to represent this integration. The conceptual framework was based on the concepts of knowledge production and sharing as applied to the collaboration between critical representative actors. Field research consisting of in-depth interviews was performed to ascertain the integration processes and their relationship with such processes of knowledge production and sharing. The results showed that the governance paradigm implemented is already empowering the citizens to contribute with intellectual capital that brings sustainability to Caguas.

PurposeThis paper aims to identify the cultural barriers that set back knowledge production and sharing in organizations of the Municipality of Caguas at the Commonwealth of the Puerto Rico in order to find effective ways to overcome them. The purpose is to explore how the enterprise promotes efficiency among employees and how they develop a suitable environment for knowledge production and sharing.Design/methodology/approachThe qualitative research consists of in‐depth interviews, carried out to management personnel, and questionnaires submitted to the employees. Two hypotheses are developed and tested using the results obtained from four organizations, public and private.FindingsThe interview responses show that at the managerial level both private and public agencies have overcome the identified barriers that set back the knowledge sharing, while from the questionnaires it is found at the employee level that several cultural barriers such as organizational environment, emotional intelligence and managers' commitment are still present.Research limitations/implicationsAlthough limited by the small sample of critical actors, this study includes international and regional organizations that serve the Municipality of Caguas. The results may set a basis to develop a methodology to analyze the presence or absence of cultural barriers in other organizations, and municipalities of Puerto Rico.Originality/valueThis investigation may be used to develop standard procedures to cope with culture differences when establishing a suitable environment for knowledge production and sharing among employees.

Background In Chile, Andes virus (ANDV) is the sole aetiological agent of hantavirus cardiopulmonary syndrome (HCPS) with mean annual incidence of 55 cases, 32% case fatality rate (CFR) and no specific treatment. Neutralizing antibody (NAb) titres at hospital admission correlate inversely with HCPS severity. We designed an open trial to explore safety and efficacy and evaluate pharmacokinetics of immune plasma as a treatment strategy for this disease. Methods We performed plasmapheresis on donors at least 6 months after HCPS and measured NAb titres through a focus-reduction neutralization test. Subjects admitted to 10 study sites with suspected/confirmed HCPS were eligible for treatment with immune plasma by intravenous infusion at an ANDV NAb dose of 5,000 U/kg. HCPS was confirmed through immunoglobulin M serology or reverse transcriptase-PCR. The main outcome was mortality within 30 days. Results From 2008–2012, we enrolled and treated 32 cases and confirmed HCPS in 29. CFR of hantavirus plasma-treated cases was 4/29 (14%); CFR of non-treated cases in the same period in Chile was 63/199 (32%; P=0.049, OR=0.35, CI=0.12, 0.99); CFR of non-treated cases at the same study sites between 2005–2012 was 18/66 (27%; ( P=0.15, OR=0.43, CI=0.14, 1.34) and CFR in a previous methylprednisolone treatment study was 20/60 (33%; P=0.052, OR=0.32, CI=0.10, 1.00). We detected no serious adverse events associated to plasma infusion. Plasma NAb titres reached in recipients were variable and viral load remained stable. Conclusions Human ANDV immune plasma infusion appears safe for HCPS. We observed a decrease in CFR in treated cases with borderline significance that will require further studies for confirmation.

When a robot manipulator has to interact with its environment, it is desirable to control the force exerted by the end-effector. There are many well-know algorithms to achieve this goal, both in Cartesian and joint coordinates. In the first case, the robot model is more complex, while in the second one inverse kinematics is to be employed, since the task is usually given in workspace coordinates. In this paper, we propose a force algorithm which does not need neither the computation of inverse kinematics nor the knowledge of the robot model. Furthermore, joint velocities are not used. Experimental results are provided to test the developed theory.

All electronic processing components in future deep nanotechnologies will exhibit high noise level and/ or low S/N ratios because of the extreme voltage reduction and the nearly erratic nature of such devices. Systems implemented with these devices would exhibit a high probability to fail, causing an unacceptably reduced reliability. In this paper we introduce an innovative input and output data redundancy principle for sequential block circuits, the responsible to keep the state of the system, showing its efficiency in front of other robust technique approaches. The methodology is totally different from the Von Neumann approaches, because element are not replicated N times, but instead, they check the coherence of redundant input data no allowing data propagation in case of discrepancy. This mechanism does not require voting devices. © 2016 Owned by the authors, published by EDP Sciences.