Using particle-in-cell simulations, we demonstrate a novel mechanism for the generation of terahertz radiation in a laser-plasma system. The radiation originates from current oscillations trapped in a stable soliton cavity created by the laser in the under-dense plasma region. These oscillations behave like a current dipole antenna. The characteristics of the antenna can be controlled by tuning the laser-plasma parameters to achieve the desired output frequency. We discuss the optimum conditions for the physical realization of this mechanism and its potential practical applications.

Background- Patients with different malocclusions may show the different activities of masticatory muscle. Masticatory muscle with neuromuscular disorder can act as an aggravating factor for a malocclusion. Patients may adopt faulty masticatory positions in case of different malocclusion, which may cause interference during orthodontic treatment. It mainly depends on muscle function or expression while recording. Aim- The current study is to evaluate the muscles’ activity using surface electromyography in the masseter, temporalis, and buccinator muscles in different malocclusions at rest, and during chewing and clenching. Material and Methods- A Total of 39 patients were examined and they were divided into 3 groups based on Angle’s classification of malocclusion- Group 1- Class I malocclusion, Group 2 – Class II malocclusion, and Group 3- Class III malocclusion. Result- At rest position, Group-1 subjects showed higher muscle function in the masseter and temporalis muscle (Mean- 18.54 ± 5.22 and 13.42 ± 4.16 respectively). Whereas, Buccinator showed enhanced performance in Group 1 subjects during chewing (Mean52.31 ± 8.98). However, no gender-wise discrepancy in the muscles was found during any of the masticatory functions or malocclusions. Conclusion- Patients with Class I malocclusion showed higher masseter activity than patients with Class II and Class III malocclusions. No gender-wise discrepancy was found in the muscle function during any of the masticatory functions or malocclusions.

The dynamics of electrons submitted to voltage pulses in a thin semiconductor layer is investigated using a kinetic approach based on the solution of the electron Boltzmann equation using particle-in-cell/Monte Carlo collision simulations. The results showed that due to the fairly high plasma density, oscillations emerge from a highly nonlinear interaction between the space-charge field and the electrons. The voltage pulse excites electron waves with dynamics and phase-space trajectories that depend on the doping level. High-amplitude oscillations take place during the relaxation phase and are subsequently damped over time-scales in the range 100–400 fs and decrease with the doping level. The power spectra of these oscillations show a high-energy band and a low-energy peak that were attributed to bounded plasma resonances and to a sheath effect. The high-energy THz domain reduces to sharp and well-defined peaks for the high doping case. The radiative power that would be emitted by the thin semiconductor layer strongly depends on the competition between damping and radiative decay in the electron dynamics. Simulations showed that higher doping level favor enhanced magnitude and much slower damping for the high-frequency current, which would strongly enhance the emitted level of THz radiation.

Mini screws – An absolute anchorage for en-mass retraction of bimaxillary dentoalveolar protrusion: A case report - JCO- Print ISSN No: - Online ISSN No:- 2582-0478 Article DOI No:- 10.18231/j.jco.2021.006, Journal of Contemporary Orthodontics-J Contemp Orthod

Data fusion can be defined as the processes of combining different types of sensor data into a common data type. Multisensor data fusion refers to the synergistic combination of sensory data from multiple sensors to provide reliable and accurate information. The challenge is how such huge data which is independently diverse can be fused. Hence there is a necessity for sophisticated and efficient data fusion techniques. Various approaches to address this problem have been found in literature and can be categorized broadly as a statistical method, generic Bayesian filter, and its derived filters, AI, deep learning, etc. In this paper, two different approaches and techniques to address the problem of sensor data fusion are presented and their comparative analysis is shown. Data fusion algorithms using a generic linear method (Kalman filter) and a nonlinear method (extended Kalman filter) have been designed in this work. Further, the challenges in a fusion of a variety of data, measured by different sensors, are addressed considering multiple-sensor-based autonomous vehicles as the application area for the current work.

Electromagnetic (EM) waves/disturbances are typically the best means to understand and analyse an ionized medium like plasma. However, the propagation of EM waves with a frequency lower than the plasma frequency is prohibited by the freely moving charges of the plasma. In dense plasmas, though the plasma frequency can be typically quite high, EM sources at such higher frequency are not easily available. It is, therefore, of interest to seek possibilities wherein a low frequency (lower than the plasma frequency) EM disturbance propagates inside a plasma. This is possible in the context of magnetized plasmas. However, in order to have a magnetized plasma response in high-density plasmas, one requires an extremely strong external magnetic field. In this manuscript, it is demonstrated that the nonlinearity of the plasma medium can aid the propagation of a slow (effective frequency lower than the plasma frequency) EM wave inside an overdense plasma. A possible mechanism of guiding, collimating, and trapping of the EM pulse or electron current pulses by appropriate tailoring of the local plasma density profile is also shown. Certain interesting applications of the propagation of such slow EM pulse through the inhomogeneous plasma is also discussed.

Proper diet and nutrition are important factors which influence the general health, growth and tissue tolerance of orthodontic patients on many levels.While orthodontist will rarely see frank manifestations of nutritional deficiencies, it should be recognized that suboptimal levels of certain nutrients are common and have an effect on the biological response of the tissues influenced by orthodontic treatment. Orthodontic treatment involves the use of attachments and forces element that can negatively affect the dietary intake compromising the nutrition of the patient. On the other hand for effective orthodontic treatment a balanced diet is required. Thus it becomes a vicious cycle. Most orthodontic patients are in the growing age. Balanced diet is essential for them. However some food in its hard and crunchy form may be avoidable during orthodontic treatment. Therefore alternate methods of intake of such food item is essential. This article highlights the importance of dietary considerations for orthodontic treatment and also how the patient can alter their dietary habits without compromising on nutrition. Keywords: Diet, Food, Orthodontic patients, Nutrition, Fruits.

The all pervading magnetic field in nature has aroused great curiosity and spawned many efforts to understand its generation. We propose, simulate, and experimentally demonstrate another mechanism of long-scale magnetic field generation in the context of a laser-plasma interaction. It relies on two realistic features, namely the finite size of the laser generated electron beam and an initial current imbalance. It is shown that magnetic fields of scale lengths comparable to the transverse beam dimension, are generated much before the onset of conventional instabilities associated with the beam-plasma system. This is due to radiative leakage at the boundaries of the finite beam, wherein even a small but finite current imbalance plays the crucial role of a radiative antenna. These features have been absent in simulations and theoretical analyses using the periodic boundary condition.

Electromagnetic (EM) waves/disturbances are typically the best means to understand and analyze an ionized medium like plasma. However, the propagation of electromagnetic waves with frequency lower than the plasma frequency is prohibited by the freely moving charges of the plasma. In dense plasmas though the plasma frequency can be typically quite high, EM sources at such higher frequency are not easily available. It is, therefore, of interest to seek possibilities wherein a low frequency (lower than the plasma frequency) EM disturbance propagates inside a plasma. This is possible in the context of magnetized plasmas. However, in order to have a magnetized plasma response one requires a strong external magnetic field. In this manuscript we demonstrate that the nonlinearity of the plasma medium can also aid the propagation of a slow EM wave inside plasma. Certain interesting applications of the propagation of such slow electromagnetic pulse through plasma is also discussed.

A new mechanism for direct laser energy coupling to heavier ion species in the presence of an external magnetic field has been illustrated. It has been shown that at higher amplitude, the ion disturbances form magnetosonic solitons. A 2D particle-in-cell simulation for an incident laser beam normal to an overdense plasma target in the presence of an external magnetic field has been carried out for this purpose. The external magnetic field is chosen such that the heavier ions remain unmagnetized but the lighter electron species get magnetized at the laser frequency. For conventional lasers of ∼1 μm wavelengths, the magnetic field requirement satisfying the aforementioned condition turns out to be of the order of several hundreds of kilo Tesla. This requirement goes down by one order if pulsed CO2 lasers with wavelengths of ∼10 μm are employed. At present, magnetic fields of several kilo Tesla have already been generated in the laboratory. Keeping this in view, the simulations have been carried out for the pulsed CO2 laser parameters. It is shown that the ion heating is enhanced considerably in the presence of an external magnetic field. Furthermore, it is shown that at a higher intensity of the laser, the ion disturbances acquire higher amplitude to excite Korteweg–de Vries magnetosonic solitons. The solitons, as expected, propagate stably for several thousands of ion plasma periods. However, subsequently, they are seen to develop transverse modulations which grow with time.

For finite systems boundaries can introduce remarkable novel features. A well known example is the Casimir effect [1, 2] that is observed in quantum electrodynamic systems. In classical systems too novel effects associated with finite boundaries have been observed, for example the surface plasmon mode [3] that appears when the plasma has a finite extension. In this work a novel instability associated with the finite transverse size of a beam owing through a plasma system has been shown to exist. This instability leads to distinct characteristic features of the associated magnetic field that gets generated. For example, in contrast to the well known unstable Weibel mode of a beam plasma system which generates magnetic field at the skin depth scale, this instability generates magnetic field at the scales length of the transverse beam dimension [4]. The existence of this new instability is demonstrated by analytical arguments and by simulations conducted with the help of a variety of Particle - In - Cell (PIC) codes (e.g. OSIRIS, EPOCH, PICPSI). Two fluid simulations have also been conducted which confirm the observations. Furthermore, laboratory experiments on laser plasma system also provides evidence of such an instability mechanism at work.

The Distributed multicast routing protocol under delay constraints, is one of the software, which requires simultaneous transmission of message from a source to a group of destinations within specified time delay. For example. Video Conferencing system. Multicast routing is to find a routing tree which is routed from the source and contains all the destinations. The principle goal of multicast routing is to minimize the network cost. A tree with minimal overall cost is called a Steiner tree. Finding such tree is the principle of the NP complete. Many inexpensive heuristic algorithms have been proposed for the Steiner tree problem. However, most of the proposed algorithms are centralized in nature. Centralized algorithm requires a central node to be responsible for computing the tree and this central node must have full knowledge about the global network. But, this is not practical in large networks. Therefore, existing algorithms suffer from the drawback such as heavy communication cost, long connection setup time and poor quality of produced routing trees. So far, a little work has been done on finding delay bounded Steiner tree in a distributed manner. An effort is made in this paper to this effect. The Study reveals that the drawbacks mentioned above has been sufficiently reduced. This paper gives complete guidelines for authors submitting papers for the AIRCC Journals.

We demonstrate by computer simulations, laser plasma experiments, and analytic theory that a hitherto unknown instability is excited in the beam plasma system with finite transverse size. This instability is responsible for the generation of magnetic fields at scales comparable to the transverse beam dimension which can be much longer than the electron skin depth scale. This counterintuitive result arises due to radiative leakage associated with finite beam boundaries which are absent in conventional infinite periodic systems considered in earlier simulations as well as theoretical analyses and may trigger a reexamination of a hitherto prevalent idea.

Fuzzy logic can be used to reason like humans and can deal with uncertainty other than randomness. Outlier detection is a difficult task to be performed, due to uncertainty involved in it. The outlier itself is a fuzzy concept and difficult to determine in a deterministic way. fuzzy logic system is very promising, since they exactly tackle the situation associated with outliers. Fuzzy logic that addresses the seemingly conflicting goals (i) removing noise, (ii) smoothing out outliers and certain other salient feature. This paper provides a detailed fuzzy logic used for outlier detection by discussing their pros and cons. Thus this is a very helpful document for naive researchers in this field.

The manuscript reports the observation of time dependent localized and non-propagating structures in the coupled laser plasma system through 1-D fluid and Particle-In-Cell (PIC) simulations. It is reported that such structures form spontaneously as a result of collision amongst certain exact solitonic solutions. They are seen to survive as coherent entities for a long time up to several hundreds of plasma periods. Furthermore, it is shown that such time dependence can also be artificially recreated by significantly disturbing the delicate balance between the radiation and the density fields required for the exact non-propagating solution obtained by Esirkepov et al., JETP 68(1), 36–41 (1998). The ensuing time evolution is an interesting interplay between kinetic and field energies of the system. The electrostatic plasma oscillations are coupled with oscillations in the electromagnetic field. The inhomogeneity of the background and the relativistic nature, however, invariably produces large amplitude density perturbations leading to its wave breaking. In the fluid simulations, the signature of wave breaking can be discerned by a drop in the total energy which evidently gets lost to the grid. The PIC simulations are observed to closely follow the fluid simulations till the point of wave breaking. However, the total energy in the case of PIC simulations is seen to remain conserved throughout the simulations. At the wave breaking, the particles are observed to acquire thermal kinetic energy in the case of PIC. Interestingly, even after wave breaking, compact coherent structures with trapped radiation inside high-density peaks continue to exist both in PIC and fluid simulations. Although the time evolution does not exactly match in the two simulations as it does prior to the process of wave breaking, the time-dependent features exhibited by the remnant structures are characteristically similar.

Outlier analysis was used since a year decade for removing the irregular annotations from data sets. Outlier exists in data sets due to unexpected faults, activities, fake behavior, human intervention error, sensor error due to atmospheric interference etc. These detections are required to identify the system faults, irregular behavior of data in some specific application for decision making and to identify the frauds. The numbers of research have been proposed by the researchers but with limited solutions. Proposed detection techniques are not quite sufficient to resolve the current issues like performance and detect the accurate outlier from the big data. This paper entails an architecture and algorithm for outlier analysis over big data. We proposed an architecture and algorithm for outlier analysis which can be useful to resolve the current issues.

The complete characterization of the exact 1-D solitary wave solutions (both stationary and propagating) for light plasma coupled system have been studied extensively in the parameter space of light frequency and the group speed [Poornakala et al., Phys. Plasmas 9(5), 1820 (2002)]. It has been shown in 1-D that solutions with single light wave peak and paired structures are stable and hence long lived. However, solutions having multiple peaks of light wave are unstable due to Raman scattering instability [Saxena et al., Phys. Plasmas 14, 072307 (2007)]. Here, we have shown with the help of 2-D fluid simulation that single peak and paired solutions too get destabilized by the transverse filamentation instability. The numerical growth rates obtained from simulations is seen to compare well with the analytical values. It is also shown that multiple peaks solitons first undergo the regular 1-D forward Raman scattering instability. Subsequently, they undergo a distinct second phase of destabilization through transverse filamentation instability. This is evident from the structure as well as the plot of the perturbed energy which shows a second phase of growth after saturating initially. The growth rate of the filamentation instability being comparatively slower than the forward Raman instability this phase comes quite late and is clearly distinguishable.