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The article presents an improved method for calculating the probability of failure-free operation of case-hardened spur gear transmissions. The existing methods for calculating the probability of failure-free operation of gear transmissions are analyzed. The failure tree for a case-hardened spur gear transmission is presented. The probability of failure-free operation of case-hardened cylindrical gear transmissions is presented as the product of the probabilities of failure-free operation of the gear and the wheel according to the following criteria (failure types): contact endurance (pitting), bending endurance (tooth breakage), and tooth interior fatigue fracture (deep contact chipping). An algorithm has been developed for calculating the probability of failure-free operation of case-hardened spur gear transmissions. To restore the torque distribution density function in the proposed method, nonparametric statistics methods are implemented. In the calculation of contact stresses, the skew angle is taken into account, which is the sum of two angles: the skew angle due to deformations of the transmission elements and the housing; the total angle of technological misalignment of wheel tooth surfaces, caused by errors in the manufacture of the teeth and mounting errors during the assembly of the transmission. An example of a test calculation of the probability of failure-free operation of a case-hardened spur gear transmission according to the presented method is given. Based on the work performed, conclusions are formulated.

The tooth interior fatigue fracture is an important criterion for the performance of a gear. The article analyzes the existing methods for determining the tooth interior fatigue fracture of cylindrical gears. Methods (Findley, V. I. Korotkina, E. I. Tesker and V. N. Syzrantsev) are validated on the basis of available experimental data. The results are presented in the form of graphs of changes in the safety factor for the depth of a case and a summary table of calculations and experimental results.

This article is devoted to the sociological analysis of the attitudes of religious xenophobia among the most socially and culturally developed part of modern Russian youth, represented by students. The research discourse is formed at the intersection of the problems of ?risk society?, revitalisation of religion, and xenophobia. The main purpose of the study is to obtain a reflexive assessment of the religious characteristics of Russian students in terms of xenophobic reactions, discrimination, and violations of citizens? rights on religious grounds. The method of data collection was a mass survey of Russian students from one of the regions of the Russian Federation. It was revealed that at least 20% of students find some extremist practices around them. The internet is the leading platform for xenophobic and extremist antisocial practices. In the environment that young people observe, religious xenophobia has a much larger scope than it would seem, and the ?isthmus? that brings it into a position of extremism is much narrower than it appears at first glance. The lack of understanding of the continuity between the phenomena of xenophobia and extremism constricts the area of management of the situation and creates the possibility of critical risks of conflicts with destructive consequences.

The article presents the results of monitoring the religious situation in the Belgorod region in 2016–2020. The methodological basis of the study is the theoretical concept of the religious situation by D.M. Ugrinovicha — I.N. Yablokov — R.A. Lopatkina and author's developments of individual indicators of religiosity. The author's methodology is presented, which allows to fix and compare various indicators of the religiosity of the population. The results of the study give an idea of the state and dynamics of religiosity in the region at the beginning of the 2020s

The article provides the theoretical reconstruction of the content and philosophical foundations of the consensual and the conventionalist concepts of scientific cognition. It is shown that the consensual concept generalizes the rational aspects of the conventionalist concept on the one hand and rejects it on the other hand. The latter refers to a) the interpretation of the subject of scientific cognition and b) understanding the criterion of the truth of scientific knowledge.

Subject. The study of the sanitary culture of rural population is an information and analytic base for the development and implementation of activities concerning the primary prevention of dental diseases on the territories of southern rural areas of Tyumen region. The aim is to estimate the social and hygienic level of skills in the population of Jurga district of Tyumen region. Materials and methods. The investigations were carried out using expeditionary and exploratory method. 200 men living in Jurga district took part in the questionnaire. The standardized questionnaire regarding the oral health developed by WHO experts (2013) was used. All men were divided according to the gender and age [at the age of 12 (n=69), at the age of 15(n=31), at the age of 35-44 (n=67), at the age of 65 and older (n=33)]. According to the data received the portrait concerning social and hygienic skills was made up for each age group. The results were processed using analytic program «Vortex 10.7.3». Results. The analysis of the received data revealed the low level of social and hygienic skills in the population of all aged groups living in Yurga district. The conducted medical and sociological questionnaire of population showed that the significant part of the population does not have knowledge of the choice of hygienic objects as well as the insignificant volume of skills of the individual oral hygiene. Also they do not have the necessity of carrying out preventive measures, dynamic check up of the oral health. Besides, the education of the population also plays a great role in the prevention of dental diseases. The tendency to the high motivation of carrying out the preventive measures was revealed in the persons having high education.

Subject. The relevance of the study is associated with the widespread prevalence of diseases of the temporomandibular joint and masticatory muscles. The large amount and inconsistency of literature data, the lack of generally accepted terminology and diagnostic criteria, and the variety of treatment methods proposed by various authors lead to difficulties in the choice of treatment tactics encountered by the dentist in everyday practice in treating patients with temporomandibular joint pathology. The goal is to study the available literature data on the prevalence and structure of clinical manifestations of functional disorders of the temporomandibular joint. Methodology. The study was conducted on the basis of a search and study of scientific publications on the epidemiology of clinical manifestations of functional disorders of the temporomandibular joint in the databases PubMed, eLibrary, Scopus, Web of Sciens, Medline. The selection of materials was carried out by keywords. Results. The review presents the scientific data of various authors on the epidemiology of the clinical manifestations of dysfunctional disorders of the temporomandibular joint. The most characteristic objective signs of the temporomandibular joint dysfunction syndrome are: “noise” phenomena in the joint during movements of the lower jaw, pain during palpation of the masticatory muscles, restriction of opening of the mouth, deviation during opening of the mouth, bruxomania, displaced position of the lower jaw relative to the upper (transverse, medial distal), the presence of otological symptoms (pain and / or a feeling of stuffiness in the ears), a burning sensation, tingling, tingling, or pain in the tongue. Conclusions. A study of the literature over the past 15 years has revealed a wide variation in the prevalence of clinical manifestations of functional disorders of the temporomandibular joint, which does not allow an unambiguous conclusion about the epidemiology of its dysfunction.

The article describes the method of General scientific ontological justification of scientific theories. Its essence consists in the following: 1) proof of the absence of logical contradiction between a particular scientific theory and a scientific picture of the world; 2) the interpretation of specific scientific theories in terms of relevant General scientific picture of the world; 3) the withdrawal of the main provisions will describe a scientific theory as a consequence of the General scientific picture of the world. The General scientific ontological justification of the scientific theory is only one of the factors of legitimization of the new theory as true along with three other forms of its legitimization: paradigmatic, epistemological and philosophical justification.

The article presents a new, pluralistic concept of the truth of scientific knowledge. It is based on two epistemological principles: 1) recognition of the social nature of scientific knowledge, 2) fixation of the level nature of the structure of scientific knowledge (in the structure of any science there are four qualitatively different levels of knowledge: sensory, empirical, theoretical and metatheoretical). Due to ontological, epistemological and methodological different levels of scientific knowledge on each of them there are special criteria of its truth. All of them have only two common features: a) each of them is a multicomponent, b) each criterion of truth has in its structure a consensual component.

Object. Dentoalveolar anomalies contribute to the development of morphological and functional disorders in the temporomandibular joint, and also lead to changes in aesthetics, chewing functions and speech formation. This report presents the results of a study of the prevalence and structure of dentoalveolar anomalies in adolescents of the indigenous minorities population of the Khanty-Mansiysk Avtonomniy Okrug ― Ugra. Data on the epidemiology of dentoalveolar anomalies are necessary for planning regional measures for the prevention of dental anomalies and deformities in the study area. The goal ― is to study the prevalence and the structure of dentoalveolar anomalies among adolescents of the indigenous minorities population of the Khanty-Mansiysk Avtonomniy Okrug ― Ugra. Methodology. Expedition and exploration method carried out a comprehensive dental examination adolescents of indigenous minorities population in a number of areas of the Khanty-Mansiysk Avtonomniy Okrug ― Ugra. Evaluation of dental status was carried out according to the criteria of the World Health Organization. In the section “dento-alveolar anomalies”, the density of teeth and gaps, as well as the main types of malocclusion, were recorded. Results. The prevalence of dentoalveolar anomalies among the surveyed was 35,4 %. The proportion of crowded teeth in the overall structure of the dental-alveolar anomalies is 30,3 %, the proportion of diastema is 2,1 %. The frequency of occlusion anomalies against the background of connective tissue dysplasia is 3,5 times higher. Summary. The high prevalence of dentoalveolar anomalies among adolescents of the indigenous minorities population of the Khanty-Mansiyskiy Avtonomniy Okrug ― Ugra was revealed. Most often, dental-alveolar anomalies were occured in the form of crowding of the upper and lower teeth, the gaps between the incisors and canines, the abnormal position of the incisors on the upper and lower jaw, changes in the closure of the molars. Dental-alveolar anomalies were more often recorded in the group of adolescents with signs of CTD.

We report on a recently developed laser-probing diagnostic which allows direct measurements of ray-deflection angles in one axis, whilst retaining imaging capabilities in the other axis. This allows us to measure the spectrum of angular deflections from a laser beam which passes though a turbulent high-energy-density plasma. This spectrum contains information about the density fluctuations within the plasma, which deflect the probing laser over a range of angles. %The principle of this diagnostic is described, along with our specific experimental realisation. We create synthetic diagnostics using ray-tracing to compare this new diagnostic with standard shadowgraphy and schlieren imaging approaches, which demonstrates the enhanced sensitivity of this new diagnostic over standard techniques. We present experimental data from turbulence behind a reverse shock in a plasma and demonstrate that this technique can measure angular deflections between 0.06 and 34 mrad, corresponding to a dynamic range of over 500., Comment: 5 pages, 4 figures. Prepared as a contributed paper for HTPD December 2020, RSI special edition

Collisional self-interactions occurring in protostellar jets give rise to strong shocks, the structure of which can be affected by radiative cooling within the flow. To study such colliding flows, we use the AstroBEAR AMR code to conduct hydrodynamic simulations in both one and three dimensions with a power law cooling function. The characteristic length and time scales for cooling are temperature dependent and thus may vary as shocked gas cools. When the cooling length decreases sufficiently rapidly the system becomes unstable to the radiative shock instability, which produces oscillations in the position of the shock front; these oscillations can be seen in both the one and three dimensional cases. Our simulations show no evidence of the density clumping characteristic of a thermal instability, even when the cooling function meets the expected criteria. In the three-dimensional case, the nonlinear thin shell instability (NTSI) is found to dominate when the cooling length is sufficiently small. When the flows are subjected to the radiative shock instability, oscillations in the size of the cooling region allow NTSI to occur at larger cooling lengths, though larger cooling lengths delay the onset of NTSI by increasing the oscillation period., Comment: 12 pages, 21 figures. Accepted for publication in MNRAS

The physics of astrophysical jets can be divided into three regimes: (i) engine and launch (ii) propagation and collimation, (iii) dissipation and particle acceleration. Since astrophysical jets comprise a huge range of scales and phenomena, practicality dictates that most studies of jets intentionally or inadvertently focus on one of these regimes, and even therein, one body of work may be simply boundary condition for another. We first discuss long standing persistent mysteries that pertain the physics of each of these regimes, independent of the method used to study them. This discussion makes contact with frontiers of plasma astrophysics more generally. While observations theory, and simulations, and have long been the main tools of the trade, what about laboratory experiments? Jet related experiments have offered controlled studies of specific principles, physical processes, and benchmarks for numerical and theoretical calculations. We discuss what has been done to date on these fronts. Although experiments have indeed helped us to understand certain processes, proof of principle concepts, and benchmarked codes, they have yet to solved an astrophysical jet mystery on their own. A challenge is that experimental tools used for jet-related experiments so far, are typically not machines originally designed for that purpose, or designed with specific astrophysical mysteries in mind. This presents an opportunity for a different way of thinking about the development of future platforms: start with the astrophysical mystery and build an experiment to address it., 37 pages, including 11 figures at the end; for New Astronomy Reviews special volume '100 Years of Jets' (eds. Rob Fender and Ralph Wijers)

This article addresses the monitoring problem of the telecommunication networks. We consider these networks as multilevel dynamic objects. It shows that reconfigurable systems are necessary for their monitoring process in real life. We implement the reconfiguration abilities of the systems through the synthesis of monitoring programs and their execution in the monitoring systems and on the end-user devices. This article presents a new method for the synthesis of monitoring programs and develops a new language to describe the monitoring programs. The programs are translated into binary format and executed by the virtual machines installed on the elements of the networks. We present an example of the program synthesis for real distributed networks monitoring at last.

This article proposes the principally new type of fault current limiter-the contactless nanographite current limiter (CNGCL). The device works like a superconductor. At some critical value of the current, it abruptly falls to zero, at which point the resistance jumps up to 6 orders of magnitude. So far, the critical current is small about a few hundreds of mA. It is shown that an increase in the length of the contact pads up to 1 m will raise the switching current up to 1 kA, while the power dissipated by the CNGCL will be about 100 kW. The possibility of heat removal using water cooling using a chiller of appropriate capacity is being considered. The analysis shows that these measures will make it possible to create a competitive current limiter for smart grids based on CNGCLs.

Starting with Peng and Heath (Academy of Management Review, 21: 492–528, 1996), the growth of the firm in emerging economies (EE) has received increasing attention in the literature in the last two decades. This line of research has not only extended our knowledge on firms’ strategic choices to the context of EE, but also proposed new perspectives on the growth of the firm. Leveraging prior research, this article focuses on three major modes for firm growth—organic, acquisitive, and network-based. For each mode, we identify new themes and insights emerging from the last two decades of research. They center on (1) compositional capabilities and frugal innovations for organic growth, (2) business groups and cross-border acquisitions for acquisitive growth, and (3) network capitalism and institutional transitions for network-based growth. Overall, we not only identify new themes and insights, but also outline important yet unresolved debates as future research directions.

Subject matter Russian Federation national program “Health Development” realizing at the present time involves the following direction “Primary prevention of dental disorder among Russian Federation population”. To achieve desired targeted indicators there is need in regional program development for preventing disease among Tyumen region population based on scientifically grounded data on the regional characteristics basis. Objectives Development of research and information basis for creating a regional program of primary prevention of dental disorder of Tyumen region population. Methodology. In accordance with the dental status registration charts (WHO, 2013) the assessment of Tyumen region dental disorders was made by questionnaire survey method. It includes a range of factors influencing its occurring such as region sick rate according to Medical center for information and analysis; presence of phenotypic manifestations of undifferentiated connective tissue dysplasia, drinking water fluoride content; eating behavior factor, hygienic education. Statistical processing of data was made by using Vortex 10.7.3 software. Results. Teeth caries intensity of study group was high and at some cases it differed from the targeted indicators of Russian Federation healthcare development program. Caries intensity of 12-year-old children from Tyumen and Tyumen region was 2,51; from North region 4,41; from South region 2,4 (target indicator equals 2,3). Caries intensity of an adult person aged from 35 to 44 years old from central and north regions was about 15,52 (target indicator equals 14,4). The periodontium progression symptoms of 15-year-old adolescents were found at 3 sextants at average (targeted indicator is 5 sextants with healthy periodontium). There was also found high incidence of intercurrent diseases and undifferentiated connective tissue dysplasia syndrome, low drinking water fluoridation, low level of hygienic education. Conclusions The regional program plan of primary prevention of Tyumen population dental disorder was developed according to the case studies data.

Magnetic reconnection is a process that contributes significantly to plasma dynamics and energy transfer in a wide range of plasma and magnetic field regimes, including inertial confinement fusion experiments, stellar coronae, and compact, highly magnetized objects like neutron stars. Laboratory experiments in different regimes can help refine, expand, and test the applicability of theoretical models to describe reconnection. Laser-plasma experiments exploring magnetic reconnection at a moderate intensity (IL ∼1014 W cm-2) have been performed previously, where the Biermann battery effect self-generates magnetic fields and the field dynamics studied using proton radiography. At high laser intensities (ILλL2>1018 Wcm-2μm2), relativistic surface currents and the time-varying electric sheath fields generate the azimuthal magnetic fields. Numerical modeling of these intensities has shown the conditions that within the magnetic field region can reach the threshold where the magnetic energy can exceed the rest mass energy such that σcold = B2/(μ0nemec2) > 1 [A. E. Raymond et al., Phys. Rev. E 98, 043207 (2018)]. Presented here is the analysis of the proton radiography of a high-intensity (∼1018 W cm-2) laser driven magnetic reconnection geometry. The path integrated magnetic fields are recovered using a "field-reconstruction algorithm" to quantify the field strengths, geometry, and evolution.

We present experimental measurements of a pulsed plasma gun, using two-colour imaging laser interferometry and spatially resolved Thomson scattering. Interferometry measurements give an electron density $n_e\approx2.7\times10^{17}$ cm$^{-3}$ at the centre of the plasma plume, at 5 mm from the plasma gun nozzle. The Thomson scattered light is collected from two probing angles allowed us to simultaneously measure the collective and non-collective spectrum of the electron feature from the same spatial locations. The inferred electron densities from the location of the electron plasma waves is in agreement with interferometry. The electron temperatures inferred from the two spectra are not consistent, with $T_e\approx 10$ eV for non-collective scattering and $T_e\approx 30$ eV for collective scattering. We discuss various broadening mechanisms such as finite aperture effects, density gradients within the collective volume and collisional broadening to account for some of this discrepancy. We also note the significant red/blue asymmetry of the electron plasma waves in the collective scattering spectra, which could relate to kinetic effects distorting the distribution function of the electrons., 12 pages, 9 figures, accepted for publication by PPCF

This paper describes a model of electron energization and cyclotron-maser emission applicable to astrophysical magnetized collisionless shocks. It is motivated by the work of Begelman, Ergun and Rees [Astrophys. J. 625, 51 (2005)] who argued that the cyclotron-maser instability occurs in localized magnetized collisionless shocks such as those expected in blazar jets. We report on recent research carried out to investigate electron acceleration at collisionless shocks and maser radiation associated with the accelerated electrons. We describe how electrons accelerated by lower-hybrid waves at collisionless shocks generate cyclotron-maser radiation when the accelerated electrons move into regions of stronger magnetic fields. The electrons are accelerated along the magnetic field and magnetically compressed leading to the formation of an electron velocity distribution having a horseshoe shape due to conservation of the electron magnetic moment. Under certain conditions the horseshoe electron velocity distribution function is unstable to the cyclotron-maser instability [Bingham and Cairns, Phys. Plasmas 7, 3089 (2000); Melrose, Rev. Mod. Plasma Phys. 1, 5 (2017)].

A supersonic flow of magnetized plasma is produced by the application of a 1 MA-peak, 500 ns current pulse to a cylindrical arrangement of parallel wires, known as an inverse wire array. The plasma flow is produced by the J × B acceleration of the ablated wire material, and a magnetic field of several Tesla is embedded at source by the driving current. This setup has been used for a variety of experiments investigating the interactions of magnetized plasma flows. In experiments designed to investigate magnetic reconnection, the collision of counter-streaming flows, carrying oppositely directed magnetic fields, leads to the formation of a reconnection layer in which we observe ions reaching temperatures much greater than predicted by classical heating mechanisms. The breakup of this layer under the plasmoid instability is dependent on the properties of the inflowing plasma, which can be controlled by the choice of the wire array material. In other experiments, magnetized shocks were formed by placing obstacles in the path of the magnetized plasma flow. The pile-up of magnetic flux in front of a conducting obstacle produces a magnetic precursor acting on upstream electrons at the distance of the ion inertial length. This precursor subsequently develops into a steep density transition via ion-electron fluid decoupling. Obstacles which possess a strong private magnetic field affect the upstream flow over a much greater distance, providing an extended bow shock structure. In the region surrounding the obstacle the magnetic pressure holds off the flow, forming a void of plasma material, analogous to the magnetopause around planetary bodies with self-generated magnetic fields., Department of Energy (Awards DE-NA0003764, DE-F03-02NA00057, DE-SC-0001063, DE-SC0016215), National Science Foundation (Award DE-SC0016215), Air Force Office of Scientific Research (Grant FA9550-17-1-0036), Engineering and Physical Sciences Research Council (EPSRC) (Grant EP/ N013379/1)

Optical collective Thomson scattering (TS) is used to diagnose magnetized high energy density physics experiments at the Magpie pulsed-power generator at Imperial College London. The system uses an amplified pulse from the second harmonic of a Nd:YAG laser (3 J, 8 ns, 532 nm) to probe a wide diversity of high-temperature plasma objects, with densities in the range of 1017–1019 cm−3 and temperatures between 10 eV and a few keV. The scattered light is collected from 100 μm-scale volumes within the plasmas, which are imaged onto optical fiber arrays. Multiple collection systems observe these volumes from different directions, providing simultaneous probing with different scattering K-vectors (and different associated α-parameters, typically in the range of 0.5–3), allowing independent measurements of separate velocity components of the bulk plasma flow. The fiber arrays are coupled to an imaging spectrometer with a gated intensified charge coupled device. The spectrometer is configured to view the ion-acoustic waves of the collective Thomson scattered spectrum. Fits to the spectra with the theoretical spectral density function S(K, ω) yield measurements of the local plasma temperatures and velocities. Fitting is constrained by independent measurements of the electron density from laser interferometry and the corresponding spectra for different scattering vectors. This TS diagnostic has been successfully implemented on a wide range of experiments, revealing temperature and flow velocity transitions across magnetized shocks, inside rotating plasma jets and imploding wire arrays, as well as providing direct measurements of drift velocities inside a magnetic reconnection current sheet.

Integrating the behavioral theory of the firm (the BTF) and the self-enhancement motive of managers, this paper examines how performance feedback—the discrepancy between actual performance and aspiration levels—affects the international expansion of emerging economy firms (EEFs). Empirical results using panel data on 876 publicly-listed Chinese manufacturing companies over a 7-year period indicate that performance relative to social aspiration (i.e., peer performance) and relative to historical aspiration (i.e., firms’ own past performance) affects EEFs’ levels of subsequent outward foreign direct investment (OFDI). Specifically, performance below social or historical aspiration enhances levels of OFDI, while the effect of performance below social aspiration is stronger than that of underperforming historical results. The results also show that performance above social aspiration enhances levels of OFDI, while performance above historical aspiration decreases levels of OFDI. Moreover, we uncover the importance of considering the joint effect of historical and social performance feedback, as receiving consistent or mixed signals about firm performance may result in risk-taking behaviors that differ from those triggered by just one performance signal on its own. These findings underscore the impact of performance feedback relative to social and historical aspirations on EEFs’ OFDI activities.

We present a new experimental platform for studying radiative shocks using an ``inverse liner z-pinch'' configuration. This platform was tested on the MAGPIE pulsed power facility (~1 MA with a rise time of ~240 ns) at Imperial College London, U.K. Current is discharged through a thin-walled metal tube (a liner) embedded in a low-density gas-fill and returned through a central post. The resulting magnetic pressure inside the liner launched a cylindrically symmetric, expanding radiative shock into the gas-fill at ~10 km/s. This experimental platform provides good diagnostic access, allowing multiframe optical self-emission imaging, laser interferometry, and optical emission spectrography to be fielded. Results from experiments with an Argon gas-fill initially at 0.04 mg/cm³are presented, demonstrating the successful production of cylindrically symmetric, expanding shocks that exhibit radiative effects such as the formation of a radiative precursor.

Astrophysical shocks are commonly revealed by the non-thermal emission of energetic electrons accelerated in situ1–3. Strong shocks are expected to accelerate particles to very high energies4–6; however, they require a source of particles with velocities fast enough to permit multiple shock crossings. While the resulting diffusive shock acceleration 4 process can account for observations, the kinetic physics regulating the continuous injection of non-thermal particles is not well understood. Indeed, this injection problem is particularly acute for electrons, which rely on high-frequency plasma fluctuations to raise them above the thermal pool7,8. Here we show, using laboratory laser-produced shock experiments, that, in the presence of a strong magnetic field, significant electron pre-heating is achieved. We demonstrate that the key mechanism in producing these energetic electrons is through the generation of lower-hybrid turbulence via shock-reflected ions. Our experimental results are analogous to many astrophysical systems, including the interaction of a comet with the solar wind 9 , a setting where electron acceleration via lower-hybrid waves is possible. Electrons can be accelerated by astrophysical shocks if they are sufficiently fast to start with. As laboratory laser-produced shock experiments reveal, this can be achieved by lower-hybrid waves generated by a shock-reflected ion instability.

This work presents a magnetic reconnection experiment in which the kinetic, magnetic, and thermal properties of the plasma each play an important role in the overall energy balance and structure of the generated reconnection layer. Magnetic reconnection occurs during the interaction of continuous and steady flows of super-Alfvénic, magnetized, aluminum plasma, which collide in a geometry with two-dimensional symmetry, producing a stable and long-lasting reconnection layer. Optical Thomson scattering measurements show that when the layer forms, ions inside the layer are more strongly heated than electrons, reaching temperatures of T [subscript]i ∼ Z T [subscript]e ≳ 300 eV--much greater than can be expected from strong shock and viscous heating alone. Later in time, as the plasma density in the layer increases, the electron and ion temperatures are found to equilibrate, and a constant plasma temperature is achieved through a balance of the heating mechanisms and radiative losses of the plasma. Measurements from Faraday rotation polarimetry also indicate the presence of significant magnetic field pile-up occurring at the boundary of the reconnection region, which is consistent with the super-Alfvénic velocity of the inflows. ©2018, Engineering and Physical Sciences Research Council (Grant no. EP/N013379/1), U.S. Department of Energy (Award no. DE-F03-02NA00057), U.S. Department of Energy (Award no. DE-SC-0001063), U.S. Department of Energy (Award no. DE-NA-0003764), Investissements d'Avenir programme (No. ANR-11-IDEX-0004-02), NSF-DOE partnership in Basic Plasma Science and Engineering (Award no. DE-SC-0016215)

Although numerous studies analyze mergers and acquisitions (M&As) in and out of developed economies (DE), a much smaller number of studies focus on M&As in and out of emerging economies (EE). Since there are significant differences in institutional environments, corporate governance practices, and markets between DE and EE, existing knowledge on acquisitions can be extended by examining M&As in and out of EE. This paper addresses this gap and identifies the main findings of studies on acquisitions in and out of EE. The review deals with EE M&A antecedents and performance outcomes, with a focus on what new insights can be gained and what new research directions are revealed. This paper also develops propositions regarding EE M&A antecedents and performance.

Radial wire array $Z$ -pinches, where wires are positioned radially outward from a central cathode to a concentric anode, can act as a compact bright X-ray source that could potentially be used to drive a hohlraum. Experiments were performed on the 7-MA Saturn generator using radial wire arrays. These experiments studied a number of potential risks in scaling radial wire arrays up from the 1-MA level, where they have been shown to be a promising compact X-ray source. Data indicate that at 7 MA, radial wire arrays can radiate $\sim 9$ TW with 10-ns full-width at half-maximum from a compact pinch.

A new rotated wire array $z$ -pinch configuration has been developed for use in experiments on the Magpie generator at Imperial College London. The wire array is rotated onto its side such that the array axis lies perpendicular to the axis of the pulsed power electrodes. This arrangement provides greatly improved end-on diagnostic access to the array and has a number of potential experimental applications; the design has recently been used to make novel Thomson scattering measurements of ablation flow interactions in tungsten wire arrays. Turning the wire array on its side leads to an uneven distribution of current through the wires due to the variation in the inductance of the current path through each wire. The forces acting on each wire will therefore be imbalanced, leading to uneven ablation of the wire cores. An experimental campaign was carried out to inductively retune the current distribution in the wire array. The results of these experiments are presented along with discussion of potential future experimental applications.

We describe magnetic reconnection experiments using a new, pulsed-power driven experimental platform in which the inflows are super-sonic but sub-Alfvénic. The intrinsically magnetised plasma flows are long lasting, producing a well-defined reconnection layer that persists over many hydrodynamic time scales. The layer is diagnosed using a suite of high resolution laser based diagnostics, which provide measurements of the electron density, reconnecting magnetic field, inflow and outflow velocities, and the electron and ion temperatures. Using these measurements, we observe a balance between the power flow into and out of the layer, and we find that the heating rates for the electrons and ions are significantly in excess of the classical predictions. The formation of plasmoids is observed in laser interferometry and optical self-emission, and the magnetic O-point structure of these plasmoids is confirmed using magnetic probes., Engineering and Physical Sciences Research Council (Grant EP/N013379/1), United States. Department of Energy (Awards DE-F03-02NA00057), United States. Department of Energy (Awards DE-SC-0001063), National Science Foundation (U.S.) (Award DE-sc0016215)

Suppressing of the core-corona structures shows a strong potential as a new breakthrough in the X-ray power production of the wire array Z-pinches. In this letter, the demonstration of suppressing the core-corona structures and its ablation using a novel double pulse current generator "Qin-1" facility is presented. The "Qin-1" facility coupled a ~10 kA 20 ns prepulse generator to a ~ 1 MA 170 ns main current generator. Driven by the prepulse current, the two aluminum wire array were mostly heated to gaseous state rather than the core-corona structures, and the implosion of the aluminum vapors driven by the main current showed no ablation, and no trailing mass. The seeds for the MRT instability formed from the inhomogeneous ablation were suppressed, however, the magneto Rayleigh-Taylor instability during the implosion was still significant and further researches on the generation and development of the magneto Rayleigh-Taylor instabilities of this gasified wire array are needed., 7 pages, 5 figures

We present an experimental study of the development and structure of bow shocks produced by the interaction of a magnetised, collisional, super-Alfvénic plasma flow with conducting cylindrical obstacles. The plasma flow with an embedded, frozen-in magnetic field (ReM ∼ 20) is produced by the current-driven ablation of fine aluminium wires in an inverse, exploding wire array z-pinch. We show that the orientation of the embedded field with respect to the obstacles has a dramatic effect on the bow shock structure. When the field is aligned with the obstacle, a sharp bow shock is formed with a global structure that is determined simply by the fast magneto-sonic Mach number. When the field is orthogonal to the obstacle, magnetic draping occurs. This leads to the growth of a magnetic precursor and the subsequent development of a magnetised bow shock that is mediated by two-fluid effects, with an opening angle and a stand-off distance, that are both many times larger than in the parallel geometry. By changing the field orientation, we change the fluid regime and physical mechanisms that are responsible for the development of the bow shocks. MHD simulations show good agreement with the structure of well-developed bow shocks. However, collisionless, two-fluid effects will need to be included within models to accurately reproduce the development of the shock with an orthogonal B-field.

We report on simulations of laboratory experiments in which magnetized supersonic flows are driven through a wire mesh. The goal of the study was to investigate the ability of such a configuration to generate supersonic, MHD turbulence. We first report on the morphological structures that develop in both magnetized and non-magnetized cases. We then analyze the flow using a variety of statistical measures, including power spectra and probability distribution functions of the density. Using these results we estimate the sonic mach number in the flows downstream of the wire mesh. We find the initially hypersonic (M=20) planar shock through the wire mesh does lead to downstream turbulent conditions. However, in both magnetized and non-magnetized cases, the resultant turbulence was marginally supersonic to transonic (M~1), and highly anisotropic in structure., Accepted to High Energy Density Physics, in press, 10 pages, 7 figures

The aim of this work is to produce and study a high energy density laboratory plasma relevant to astrophysical accretion disks. To this end, an experimental setup based on a modified cylindrical wire array was devised, which employs a cusp magnetic field to introduce angular momentum into the system. The setup was studied numerically with the three-dimensional, resistive magneto-hydrodynamic code GORGON. Simulations show that a differentially-rotating flow is formed, with typical rotation velocity and Mach number values of 60 km/s and Mφ ∼ 5 respectively. The plasma is radiatively cooled and presents a Reynolds number higher than 107. In addition, the magnetic Reynolds number and the plasma β are >1. Such a plasma is of interest for the study of hydrodynamic and magneto-hydrodynamic instabilities, and turbulence generation in differentially-rotating plasma flows.