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An investigation of risk factors has been identified as a crucial aspect of the routine management of rockburst. However, the identification methods for principal impact factors and the examination of the relationship between seismic energy and other source parameters have not been extensively explored to conduct dynamic risk management. This study aims to quantify impact risk factors and discriminate hazardous high-energy seismic events. The analytic hierarchy process (AHP) and entropy weight method (EWM) are utilized to ascertain the primary control factors based on geotechnical data and nearly two months of seismic data from a longwall panel. Furthermore, the distribution law and correlation relationship among seismic source parameters are systematically analyzed. Results show that the effect of coal depth, coal seam thickness, coal dip, and mining speed covers the entire mining process, while the fault is only prominent in localized areas. There are varying degrees of log-positive correlations between seismic energy and other source parameters, and this positive correlation is more pronounced for hazardous high-energy seismic events. Utilizing the linear logarithmic relationship between seismic energy and other source parameters, along with the impact weights of dynamic risks, the comprehensive energy index for evaluating high-energy seismic events is proposed. The comprehensive energy index identification method proves to be more accurate by comparing with the high-energy seismic events based on energy criteria. The limitations and improvements of this method are also synthesized to obtaining a wide range of applications. [ABSTRACT FROM AUTHOR]

Berberine (BBR) is used to treat cancer, inflammatory conditions, and so on. But the side effects of BBR causing constipation should not be ignored. In clinical application, the combination of Amomum villosum Lour. (AVL) and BBR can relieve it. However, the effective ingredients and molecular mechanism of AVL in relieving constipation are not clear. A small intestine propulsion experiment was conducted in constipated mice to screen active ingredients of AVL. We further confirmed the molecular mechanism of action of the active ingredient on BBR-induced constipation. Quercetin (QR) was found to be the effective ingredient of AVL in terms of relieving constipation. QR can efficiently regulate the microbiota in mice suffering from constipation. Moreover, QR significantly raised the levels of substance P and motilin while lowering those of 5-hydroxytryptamine and vasoactive intestinal peptide; furthermore, it also increased the protein expression levels of calmodulin, myosin light-chain kinase, and myosin light chain. The use of QR in combination with BBR has an adverse effect-reducing efficacy. The study provides new ideas and possibilities for the treatment of constipation induced by BBR. [ABSTRACT FROM AUTHOR]

Space-based gravitational wave detection is extremely sensitive to disturbances. The Keplerian configuration cannot accurately reflect the variations in spacecraft configuration. Planetary gravitational disturbances are one of the main sources. Numerical simulation is an effective method to investigate the impact of perturbation on spacecraft orbits. This study shows that, in the context of the Taiji project, Earth's gravity is an essential factor in the change in heliocentric formation configuration, contributing to the relative acceleration between spacecrafts in the order of O (10 − 6) m · s − 2 . Considering 00:00:00 on 27 October 2032 as the initial orbiting moment, under the influence of Earth's gravitational perturbation, the maximum relative change in armlengths and variation rates of armlengths for Taiji is 1.6 × 10 5 km , 32 m · s − 1 , respectively, compared with the unperturbed Keplerian orbit. Additionally, by considering the gravitational perturbations of Venus and Jupiter, the armlength and relative velocity for Taiji are reduced by 16.01 % and 17.45 % , respectively, compared with when only considering that of Earth. The maximum amplitude of the formation motion indicator changes with the orbit entry time. Results show that the relative velocity increase between the spacecrafts is minimal when the initial orbital moment occurs in July. Moreover, the numerical simulation results are inconsistent when using different ephemerides. The differences between ephemerides DE440 and DE430 are smaller than those between DE440 and DE421. [ABSTRACT FROM AUTHOR]

To meet the demand for higher performance and wearability, integrated circuits are developing towards having multilayered structures and greater flexibility. However, traditional circuit fabrication methods using etching and lamination processes are not compatible with flexible substrates. As a non-contact printing method in additive manufacturing, electrohydrodynamic printing possesses advantages such as environmental friendliness, sub-micron manufacturing, and the capability for flexible substrates. However, the interconnection and insulation of different conductive layers become significant challenges. This study took composite silver ink as a conductive material to fabricate a circuit via electrohydrodynamic printing, applied polyimide spraying to achieve interlayer insulation, and drilled micro through-holes to achieve interlayer interconnection. A 200 × 200 mm2 ten-layer flexible circuit was thus prepared. Furthermore, we combined a finite element simulation with reliability experiments, and the prepared ten-layer circuit was found to have excellent bending resistance and thermal cycling stability. This study provides a new method for the manufacturing of low-cost, large-sized, multilayer flexible circuits, which can improve circuit performance and boost the development of printed electronics. [ABSTRACT FROM AUTHOR]

In response to the increasingly severe situation of main roadway shock in coal seams, with a focus on the strong-bump coal seam in main roadways under an asymmetric goaf in a certain mine, theoretical analysis, numerical simulation, and engineering practices were employed. This study investigated factors influencing main roadway roof shock damage, changes in roof stress, and characteristics of overlying strata movement. This research unveiled the mechanism and prevention of roof shock in main roadways of strong-bump coal seams in an asymmetric goaf. The research results indicate that the influencing factors of main roadway roof shock damage can be divided into two categories: "strata-support" structure strength and surrounding rock stress. For the determination of the "strata-support" structure, in the case of strong bumps in coal seam roadways influenced by the asymmetric goaf, the key factors contributing to shock damage are the side abutment pressure on the coal pillar in the goaf and the activity level of the roof strata. The distribution of roof stress in the main roadway undergoes continuous changes as district faces are sequentially mined. When the goaf area on the west side gradually increases towards the south, the roof stress in the main roadway consistently rises, and the stress increment follows a pattern of initial increase followed by a decrease. The strata structure of the main roadway roof gradually transforms from an "asymmetric T" shape to a "symmetric T" shape in the transverse profile, and with the evolution of the roof rock layer structure, the mutual feedback effect of strata activity on both sides of the roadway gradually strengthens. Affected by the asymmetric goaf, the main roadway in the district undergoes three different stages: one side of subcritical mining influence → both sides of subcritical mining influence → one side of subcritical mining and one side of critical mining influence. In addition, comprehensively considering the impact of various factors in different stages, the theoretical criteria for roof shock failure in the main roadway are determined. The formulation of an optimized position for the main roadway and a scheme for depressurization through deep-hole blasting in the roof reduce the stress level in the surrounding rock of the main roadway, effectively preventing the occurrence of roof shock in the asymmetric goaf of the coal seam main roadway. [ABSTRACT FROM AUTHOR]

Demantoid is the green variety of andradite [Ca3Fe2(SiO4)3], an exceptionally rare and precious gemstone worldwide. In recent years, a small amount of gem-quality demantoid has been found in Pakistan. This research focuses on nine demantoids sourced from Muslim Bagh, Baluchistan, Pakistan, presenting a comprehensive analysis of the spectral characteristics and inclusions of Pakistani demantoid using classical gemological methods, energy dispersive X-ray fluorescence (EDXRF) chemical analyses, Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and ultraviolet and visible (UV-vis) spectroscopy. The results show that the content of Cr and V in most samples is lower than the detection line of EDXRF, with only one sample containing a Cr2O3 content of 0.032%. The extremely low Cr content sets Pakistani demantoid apart from demantoid of the serpentinite type found in other regions. Notably, the UV-vis spectrum reveals characteristic absorption at 443 nm due to Fe3+, while a further contribution from Cr3+ would be highly likely, and weak absorption at 550 nm caused by Fe3+. This suggests that iron (Fe) is the primary chromogenic element of Pakistani demantoid, but the role of Cr3+ cannot be ignored. The FTIR spectrum of Pakistani demantoid displays the absorption peaks associated with [SiO4]4− groups at 937 cm−1, 848 cm−1, and 817 cm−1, while the absorption peaks resulting from trivalent cations appear at 481 cm−1 and 442 cm−1, which are the characteristic FTIR spectra of demantoid. Raman spectroscopy further reveals absorption peaks are displayed near 994 cm−1, 843 cm−1, 818 cm−1, associated with (Si–O)Str vibrations (Si–O stretching vibration), and absorption peaks are displayed near 350 cm−1 and 310 cm−1, related to the rotation of SiO4–R(SiO4)4−, and the peaks near 514 cm−1 and 494 cm−1 are related to (Si–O)bend vibrations (Si–O bending vibration). Additionally, related absorption peaks near 168 cm−1 are attributed to the translation of SiO4–T(SiO4)4−, and absorption peaks near 234 cm−1 are associated with the translation of X2+–T(X2+) (X2+ represents divalent ions). The common dark opaque inclusions found in Pakistani demantoid consist of a combination of magnetite and hematite. Additionally, some samples of Pakistani demantoid display inclusions of calcite. This unique combination of inclusions differentiates Pakistani demantoid from demantoids sourced from other regions. It signifies that Pakistani demantoid has a distinctive geological origin resulting from the interplay of serpentinization and skarnization processes. This geological formation distinguishes it from demantoids solely hosted in serpentinite or skarn environments in other origins. The identification of these characteristics holds significant importance for accurately determining the origin of Pakistani demantoid. [ABSTRACT FROM AUTHOR]