Constraints on anomalous quartic gauge couplings via WγjjW\gamma jj production at the LHC

The vector boson scattering at the Large Hadron Collider (LHC) is sensitive to anomalous quartic gauge couplings (aQGCs). In this paper, we investigate the aQGC contribution to $W \gamma jj$ production at the LHC with $\sqrt{s}=13$ TeV in the context of an effective field theory (EFT). The unitarity bound is applied as a cut on the energy scale of this production process, which is found to have significant suppressive effects on the signals. To enhance the statistical significance, we analyse the kinematic and polarization features of the aQGC signals in detail. We find that the polarization effects induced by the aQGCs are unique and can discriminate the signals from the SM backgrounds well. With the proposed event selection strategy, we obtain the constraints on the coefficients of dimension-8 operators with current luminosity. The results indicate that the process $pp \to W \gamma jj$ is powerful for searching for the $O_{M_{2,3,4,5}}$ and $O_{T_{5,6,7}}$ operators.Comment: 29 pages, 11 figures, 7 tables, to be published in Chinese Physics

Oscillations of complex networks

A complex network processing information or physical flows is usually characterized by a number of macroscopic quantities such as the diameter and the betweenness centrality. An issue of significant theoretical and practical interest is how such a network responds to sudden changes caused by attacks or disturbances. By introducing a model to address this issue, we find that, for a finite-capacity network, perturbations can cause the network to \emph{oscillate} persistently in the sense that the characterizing quantities vary periodically or randomly with time. We provide a theoretical estimate of the critical capacity-parameter value for the onset of the network oscillation. The finding is expected to have broad implications as it suggests that complex networks may be structurally highly dynamic.Comment: 4 pages, 4 figures. submitte

Plasma removal of Parylene C

Parylene C, an emerging material in microelectromechanical systems, is of particular interest in biomedical and lab-on-a-chip applications where stable, chemically inert surfaces are desired. Practical implementation of Parylene C as a structural material requires the development of micropatterning techniques for its selective removal. Dry etching methods are currently the most suitable for batch processing of Parylene structures. A performance comparison of three different modes of Parylene C plasma etching was conducted using oxygen as the primary reactive species. Plasma, reactive ion and deep reactive ion etching techniques were explored. In addition, a new switched chemistry process with alternating cycles of fluoropolymer deposition and oxygen plasma etching was examined to produce structures with vertical sidewalls. Vertical etch rates, lateral etch rates, anisotropy and sidewall angles were characterized for each of the methods. This detailed characterization was enabled by the application of replica casting to obtain cross sections of etched structures in a non-destructive manner. Application of the developed etch recipes to the fabrication of complex Parylene C microstructures is also discussed

Genetic insights on sleep schedules: this time, it's PERsonal.

The study of circadian rhythms is emerging as a fruitful opportunity for understanding cellular mechanisms that govern human physiology and behavior, fueled by evidence directly linking sleep disorders to genetic mutations affecting circadian molecular pathways. Familial advanced sleep-phase disorder (FASPD) is the first recognized Mendelian circadian rhythm trait, and affected individuals exhibit exceptionally early sleep-wake onset due to altered post-translational regulation of period homolog 2 (PER2). Behavioral and cellular circadian rhythms are analogously affected because the circadian period length of behavior is reduced in the absence of environmental time cues, and cycle duration of the molecular clock is likewise shortened. In light of these findings, we review the PER2 dynamics in the context of circadian regulation to reveal the mechanism of sleep-schedule modulation. Understanding PER2 regulation and functionality may shed new light on how our genetic composition can influence our sleep-wake behaviors

Stab Resistant Analysis For Body Armour Design Features Manufactured Via Fused Deposition Modeling Process

Stab resistant body armour is a type of protective equipment worn to prevent from sustaining severe injuries caused by the sharp weapons. Despite many efforts have been devoted to enhance the protection and manoeuvrability of the body armour, current protective solutions continue to present a number of issues which has shown to affect the work performance of the wearers. Yet the application of additive manufacturing (AM) technology has potentially presented as an alternative solution to produce light weight body armour that able to provide adequate protection and performance characteristics due to the nature of AM build process. This research therefore attempted to investigate the feasibility to manufacture five designs of imbricate scale armour features for stab resistant application via Fused Deposition Modeling (FDM) process in order to meet the requirement of the knife resistance (KR) level one of the current HOSDB stab-resistant body armour standard with impact energy of 24 Joules. To do this, knife blades were fabricated in accordance with the international standard and securely installed to the Instron CEAST 9340 Drop Impact Tower which used to impact test on the test specimens. The test specimens were manufactured via Stratasys Fortus 400mc machine using two of the basis FDM filament materials including ABS-M30 and PC-ABS for a light weight stab resistant body protective armour. Prior to the experimental stab test, a preliminary study was performed via ANSYS which is a finite element analysis software to analyse stab resistance performance of these materials. Then, stab experimental test was conducted on both of the materials measured thickness ranging from 4.0 mm to 6.0 mm to ensure a proper material selection for stab resistance. By using the selected material, stab test was further conducted on the specimens measured thickness ranging from 7.0 mm to 10.0 mm to determine a minimum thickness resulted with a knife penetration through the underside which did not exceed the maximum penetration permissibility of 7.0 mm, as defined within HOSDB KR1-E1. The minimum thickness was then used to develop a series of designs incorporated with different imbricate scale-like features and stab tested to analyse their stab-resistant performance. Finally, one of the design which offered the highest knife penetration resistance was selected. Result obtained in the finite element analysis demonstrated the total deformation distributed in most of the PC-ABS specimens was lower than ABS-M30. This was also demonstrated in the stab experimental test of PC-ABS specimens which showed less shattering cases and lower overall knife penetration depth in comparison with ABS-M30. By using PC-ABS, further stab test demonstrated a minimum thickness of 8.0 mm can be used for the development of FDM-manufactured body armour design features. Lastly, the design feature of D5 has shown to exhibit the highest resistance to the knife penetration due to the penetration depth of 3.02 mm occurred in it was the lowest compared to other design features

Chess-Board-Like Spatio-Temporal Interference Patterns and Their Excitation

We discover new type of interference patterns generated in the focusing nonlinear Schr\"odinger equation (NLSE) with localised periodic initial conditions. At special conditions, found in the present work, these patterns exhibit novel chess-board-like spatio-temporal structures which can be observed as the outcome of collision of two breathers. The infinitely extended chess-board-like patterns correspond to the continuous spectrum bands of the NLSE theory. More complicated patterns can be observed when the initial condition contains several localised periodic swells. These patterns can be observed in a variety of physical situations ranging from optics and hydrodynamics to Bose-Einstein condensates and plasma.Comment: 6 pages, 5 figure