Laser biomodification of the bone bed surface for placement of spiral dental implants: a study based on scanning electron microscopy

Introduction: Various rotary and mechanical instruments are used in conventional oral surgery for osteotomies. Despite the implementation of effective cooling systems, it is difficult to prevent thermal damage to the adjacent bone caused by heat generated during the procedure. A smear layer forms on the surface, which can impede the interaction of blood elements with the underlying tissue, resulting in a delayed healing process. Aim: This study explores the possibility of overcoming these drawbacks by combining conventional methods with a pulsed Er:YAG laser. By examining the osteotomy surfaces using scanning electron microscopy (SEM), we investigated the potential synergistic effects that could benefit conventional implantology. Materials and methods: Split osteotomies were performed on mandibles of freshly euthanized domestic pigs (Sus scrofa domestica). With osteotomy surface examination, the experimental comparison involved two groups: group A - standard technique, and group B - surface ablation using an Er:YAG laser by applying our own method. The samples from both groups were examined using scanning electron microscopy (SEM). Results: In group A samples, the bone surface was smooth, with an amorphous layer and microcracks all over it. The thickness of this layer ranged from 21.77 µm to 136.2 µm, completely obstructing the Volkmann’s and Haversian canals. In group B, the borders were smooth and well defined. The bone structure remained unchanged, with empty intratrabecular spaces, no signs of carbonization, and open canals reaching the surface. The smear layer measured between 3.054 µm and 47.26 µm, with complete absence observed in some places. Conclusions: The present study provides evidence that ablation of the osteotomy surface using an Er:YAG laser leads to biomodification by eliminating the smear layer without altering the parameters of the bone bed

Innovative development of a flying robot with a flexible manipulator for aerial manipulations

This paper presents an innovative development of a flying robot or an aerial robot, with a flexible manipulator, called the Dexterous Aerial Robotic System (DFTS), for aerial manipulations, especially for inspections and reparations of various structures such as wind turbines, power lines and open gas pipelines, decorations and painting of high industrial chimneys and walls of high buildings, as well as transport and delivery of courier shipments, relocation and manipulation of assemblies and units in inaccessible or dangerous environments. The proposed DFTS consists of two independent but interconnected systems or functional units, which have two main separate functions respectively, including a basic carrying function, and a precise positioning and stabilization function. The system with a basic carrying function is actually the main flying system, the un-manned aerial vehicle (UAV); it is remotely controlled and piloted. Meanwhile, the aerial manipulation platform, called the vertical take-off and landing platform VTOL, which is an active flying platform with 6 degrees of freedom (DOF) is used for positioning and stabilization; and it is attached to the UAV via the soft link. With the use of a long soft link, the problems which are caused by the air turbulent flows generated by the UAV are minimized, and the aerial manipulations of objects are safely controlled and operated. The VTOL which is equipped with a grasping mechanism was successfully developed, prototyped and tested. The experimental results showed that, the developed VTOL can self-stabilize with the inclination angle of being up to 8 degrees

Development of a smart system for early detection of forest fires based on unmanned aerial vehicles

The naturally occurring wildfires and the people-related forest fires are events, which in many cases have significant impact on the environment, the wildlife and the human population. The most devastating among these events usually start in unpopulated remote areas, which are difficult to inspect or are not constantly being monitored or observed. This gives the local small-sized fires enough time to evolve into full-scale wide-area disasters, which in turn makes their suppression and extinguishing very difficult. In this paper, we present an autonomous system for early detection of forest fires, named THEASIS-M. The presented system represents a solution that is based on a combination of innovative technologies, including computer vision algorithms, artificial intelligence and unmanned aerial vehicles. In the first part of the study, we provide an overview on the present applications of the UAVs in the forestry domain. The paper then introduces the general architecture of the THEASIS-M system and its components. The system itself is fully autonomous and is based on several different types of UAVs, including a fixed-wing drone, which provides the overall forest monitoring capabilities of the proposed solution, and a rotary-wing UAV that is used for confirmation and monitoring of the detected fire event. The widely used technologies for computer vision and image processing, which are used for the detection of fire and smoke in the real-time video streams sent from the UAVs to the ground control station, are highlighted in the next section of this study. Finally, the experimental tests and demonstrations of the proposed THEASIS-M system are presented and briefly discussed

Azimuthal anisotropy of charged jet production in root s(NN)=2.76 TeV Pb-Pb collisions

We present measurements of the azimuthal dependence of charged jet production in central and semi-central root s(NN) = 2.76 TeV Pb-Pb collisions with respect to the second harmonic event plane, quantified as nu(ch)(2) (jet). Jet finding is performed employing the anti-k(T) algorithm with a resolution parameter R = 0.2 using charged tracks from the ALICE tracking system. The contribution of the azimuthal anisotropy of the underlying event is taken into account event-by-event. The remaining (statistical) region-to-region fluctuations are removed on an ensemble basis by unfolding the jet spectra for different event plane orientations independently. Significant non-zero nu(ch)(2) (jet) is observed in semi-central collisions (30-50% centrality) for 20 <p(T)(ch) (jet) <90 GeV/c. The azimuthal dependence of the charged jet production is similar to the dependence observed for jets comprising both charged and neutral fragments, and compatible with measurements of the nu(2) of single charged particles at high p(T). Good agreement between the data and predictions from JEWEL, an event generator simulating parton shower evolution in the presence of a dense QCD medium, is found in semi-central collisions. (C) 2015 CERN for the benefit of the ALICE Collaboration. Published by Elsevier B.V. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).Peer reviewe

Production of He-4 and (4) in Pb-Pb collisions at root(NN)-N-S=2.76 TeV at the LHC

Results on the production of He-4 and (4) nuclei in Pb-Pb collisions at root(NN)-N-S = 2.76 TeV in the rapidity range vertical bar y vertical bar <1, using the ALICE detector, are presented in this paper. The rapidity densities corresponding to 0-10% central events are found to be dN/dy4(He) = (0.8 +/- 0.4 (stat) +/- 0.3 (syst)) x 10(-6) and dN/dy4 = (1.1 +/- 0.4 (stat) +/- 0.2 (syst)) x 10(-6), respectively. This is in agreement with the statistical thermal model expectation assuming the same chemical freeze-out temperature (T-chem = 156 MeV) as for light hadrons. The measured ratio of (4)/He-4 is 1.4 +/- 0.8 (stat) +/- 0.5 (syst). (C) 2018 Published by Elsevier B.V.Peer reviewe