The Ethnographic Approach in the Digital Scenario

In this chapter, the goal is to formalize the main differences between the applications of ethnographic techniques when they are framed in virtual or digital methods. To be more systematic in presenting these differences, a synoptic table will be offered. This table will examine the main breaking points between the methods and will be used to organize a marked comparison between studies chosen from the most cited articles of the last 20 years. In addition to testing the effectiveness of the proposed classification scheme, the purpose of the comparison conducted between the most cited articles will be to highlight where the changes that have occurred can lead to advances in the method and where these changes have become new limits on which it is necessary to continue to reflect in order to develop the methods involved and place them clearly in line with the evolution of the digital scenario.

Die Form des ›Helfens‹ und ihre (Soll-)Bruchstellen

As familiar and self-evident as what is meant by ›helping‹ may seem at first, it is difficult to define ›helping‹ in a precise conceptual way. Against this backdrop, the question of what ›helping‹ is will be taken up and dealt with from a theoretical point of view. The path taken to work out and systematically define the form of helping leads to the discussion of some of the (predetermined) breaking points built into it and to the conclusion that ›helping‹ must be categorically defined differently. Recent anthropological research also suggests this by referring to the social-theoretical embedding of individuals and leaving behind individual-theoretical understandings of isolated individuals who would then enter into a relationship with each other.

Evaluation of Injectable Hyaluronic Acid-Based Hydrogels for Endodontic Tissue Regeneration

Dental pulp tissue engineering (TE) endeavors to regenerate dentin/pulp complex by combining a suitable supporting matrix, stem cells, and biochemical stimuli. Such procedures foresee a matrix that can be easily introduced into the root canal system (RCS) and tightly adhere to dentin walls to assure the dentin surface’s proper colonization with progenitor cells capable of restoring the dentin/pulp complex. Herein was investigated an injectable self-setting hyaluronic acid-based (HA) hydrogel system, formed by aldehyde-modified (a-HA) with hydrazide-modified (ADH), enriched with platelet lysate (PL), for endodontic regeneration. The hydrogels’ working (wT) and setting (sT) times, the adhesion to the dentine walls, the hydrogel’s microstructure, and the delivery of human dental pulp cells (DPCs) were studied in vitro. Hydrogels incorporating PL showed a suitable wT and sT and a porous microstructure. The tensile tests showed that the breaking point occurs after 4.3106 ± 1.8677 mm deformation, while in the indentation test after 1.4056 ± 0.3065 mm deformation. Both breaking points occur in the hydrogel extension. The HA/PL hydrogels exhibited supportive properties and promoted cell migration toward dentin surfaces in vitro. Overall, these results support using PL-laden HA injectable hydrogels (HA/PL) as a biomaterial for DPCs encapsulation, thereby displaying great clinical potential towards endodontic regenerative therapies.

Track-Before-Detect Procedures in AM Radio-Based Passive Radar

In amplitude modulation radio-based passive radar, the track-before-detect (TBD) procedures are performed to process long time observation data. This work mainly focuses on the tracking of the time-Doppler and time-azimuth traces of multiple target under real scenarios such as low signal-to-noise ratio, hybrid clutter, severe breaking points, and intersecting traces. A new original approach to deal with the TBD problem of this work is developed. Two types of linear equations according to the simplified radio wave propagation model are formulated, which is the key point of the proposed method. We make the theoretical analysis about how the linear equations can be used to track multiple target, and how multiple target’s constant velocities and initial positions can be estimated, which is an additional parameter estimation capability of the proposed method. Both the simulated data and real experimental data are performed with the proposed method and some conventional TBD methods. Several comparisons of the results are given to verify the effectiveness of the proposed method.

Evaluation of Injectable Hyaluronic Acid-Based Hydrogels for Endodontic Tissue Regeneration

Dental pulp tissue engineering (TE) quests to regenerate dentin/pulp complex by combining a suitable supporting matrix, stem cells, and biochemical stimuli. Such procedures foresee a matrix that can be easily introduced into the root canal system (RCS) and tightly adhere to dentin walls to assure the dentin surface's proper colonization with progenitor cells capable of restoring the dentin/pulp complex. Herein was investigated an injectable self-setting hyaluronic acid-based (HA) hydrogel system, formed by aldehyde-modified (a-HA) with hydrazide-modified (ADH), enriched with platelet lysate (PL), for endodontic regeneration. The hydrogels' working (wT) and setting (sT) times, the adhesion to the dentine walls, the hydrogel's microstructure, and the delivery of human Dental Pulp Cells (DPCs) were studied in vitro. Hydrogels incorporating PL showed a suitable wT and sT and a porous microstructure. The tensile tests showed that the breaking point occurs after 4.13 mm deformation. While in the indentation test after 1.3 mm deformation. Both breaking points occur in the hydrogel extension. The HA/PL hydrogels exhibited supportive properties and promoted cell migration toward dentin surfaces in vitro. Overall, these results support using PL-laden HA injectable hydrogels (HA/PL) as a biomaterial for DPCs encapsulation, thereby displaying great clinical potential towards endodontic regenerative therapies.

Virtual vs Digital: Examples of Netnography and Digital Ethnography in Tourism Studies for a Comparison between Methods

With this paper our goal is to formalize the main differences between the applications of ethnographic techniques when they are framed in Virtual or Digital Methods. To be more systematic in presenting these differences, a synoptic table is offered. This table examines the main breaking points between the methods and is used to organize a marked comparison between two tourism studies chosen as being representative; one for the ethnographic application of Virtual Methods, and one for the ethnographic application of Digital Methods. In addition to testing the effectiveness of the proposed classification scheme, the purpose of the comparison conducted between the two tourism studies is to highlight where the changes that have occurred can lead to advances in the method and where these changes have become new limits on which it is necessary to continue to reflect in order to develop the methods involved and place them clearly in line with the evolution of the digital scenario. Keywords: Virtual Methods, Digital Methods, Netnography, Digital Ethnography, Tourism Studies.

Regularities of Methane and Coal Dust Ignition Caused by Electric Sources in Mine Workings

Fires and explosions pose the greatest threat in underground mines that use high-voltage electrical grids. The paper presents data on explosions of combustible methane and coal dust mixtures in Russian mines. It is shown that there always exists a high risk of fire resulting from a malfunction in the electrical grid. The research aims at determining the type and parameters of an electric arc, spark or open flame generated at the breaking points of electric conductors which initiate the ignition of a combustible medium. It was found that the commonly known ionic and thermal theories of ignition do not match the present state of knowledge. The methodology consisted in investigating patterns of electric charge generation and transfer up to the point of the mains failure. Regularities of energy processes in the atomic and molecular structure of the conductor material are presented. For the first time ever the concept of transformation of the electromagnetic energy generated in the alternator into photon packets of high-frequency energy is justified. An electron of the conductor atom absorbs a quantum of the generated energy, converts the generated frequency into a high-frequency photon packet and radiates it into the electric grid. It has been found that an electric arc or a spark, acting as a source of ignition for a combustible medium, is an electromagnetic emission of energy in the visible range.

Opening forces or failure of commercially available equine headcollars and other safety devices

A recent survey by the authors of the present study indicated that headcollar (halter, USA) related incidents resulting in horse injuries may be common. From the survey, 134 incidents involving horse fractures and 167 fatalities were reported. Headcollar design and materials vary markedly from traditional leather to “safety” headcollars and safety devices. Despite their almost universal use, there has been minimal study as to how these items function or specifications for performance. The aim of the present study was to select a range of commercially available standard headcollars and a number of safety devices, to test the force required to break or release them. Safety devices selected included baler twine, which is widely used by equestrians to attach a horse by a headcollar to a lead rope and in turn to a fixture. This system practice is perceived to increase safety. Devices were subjected to increasing load in the poll to lead-rope attachment axis (i.e. to simulate a horse pulling backward) using a custom-made steel rig incorporating an electric 1000 kg winch. The force was increased incrementally until either the headcollar or device opened or failed. The lowest mean opening force of 357 ± 50 N was for a safety headcollar, which is equivalent to a load of approximately 36 kg. The highest breaking force was 5798 ± 265 N for one of the eight different webbing headcollars tested. Breaking for safety devices ranged from 354 ± 121 N for “fine” baler twine to 1348 ± 307 N for a “heavy duty” baler twine. Variability in opening force was lowest in two of the webbing headcollars (CV < 5%) despite these having very high breaking points (>3500 N). The greatest variability was found for fine baler twine (CV = 34%) and one of the commercial safety devices (CV = 38%). The range of opening forces and variability in opening forces for standard headcollars, safety headcollars and safety devices is a cause for concern and may give horse owners/handlers a false sense of security with regards to safety, and actually predispose horses and handlers to an increased risk of injury.

Current Trends in the Development of International Terrorism: A Current Understanding of the Problem

The study examines the development of international terrorism and the problem of its definition. Consequently, the objective of the study was to generate a systemic view of international terrorism and to identify current trends in its development. A structural and functional analysis of international terrorism as a political phenomenon was used. Based on the analytical model provided, the development of international terrorism was divided into periods based on political and geographical zoning. Three consistent principles determine the key characteristics of international terrorism as a rational strategy of unconventional political struggle: the transition to asymmetrical actions, attacks on symbolic objects, and influencing public opinion as the main objective. This triality of characteristics linked to a model of the political process defines the existence of international terrorism as a phenomenon and provides a key to understanding its dynamics. It is concluded that there are four periods in the development of international terrorism, divided into two cycles with breaking points, ascending, and descending phases. The proposed periodization of the development of international terrorism is based on the identification of the centers as political-geographical areas, where contradictions are configured and the political struggle that is part of the logic of the terrorist strategy.