External Impact Research Articles

Numerical simulation of cable sheath damage detection based on torsional mode guided wave

In view of the cracking, sag, and damage of sheath caused by the load effect and external force impact of power cable, the echo parameters of cable sheath damage detection based on the characteristics of torsional guided wave propagation are studied in this work. According to the Navier displacement equilibrium equation, the dispersion curve of a magnetostrictive guided wave of the cable sheath was solved, and the T(0,1) mode with a group velocity of 1198.8 m/s and no dispersion was selected. Furthermore, while considering the excitation frequency, loss rate, and direction of the damaged section, the displacement field and the echo characteristic parameters of guided wave in the cable sheath were solved. Moreover, by analyzing the time-domain signals of damaged section echo, the cubic fitting function for the loss rate of the damaged section and the damaged section echo coefficient were obtained, which can effectively characterize the quantitative relationship between the damaged location, size, and guided wave echo of the cable sheath.

Mussel-inspired tough ionogel with robust adhesion and mechanical adaptivity for impact resistance

Intrinsic adhesiveness and mechanical adaptivity allowing spontaneous anchoring and impact-stiffening, which facilitate safer impact protection, remain challenges for the design and synthesis of advanced tough impact-resistant materials. Herein, a novel biomimetic mechanically robust impact-resistant ionogel with the mussel-inspired diphasic structure was elaborately developed. The salt-bridge hydrogen bonds between carboxyl and imidazole groups inside rigid clusters serve as reversible crosslinking sites and prime energy-dissipation motifs, leading to strong noncovalent cohesion. Furthermore, the hydrophobic ionic liquid enriches surface interactions, providing extensive adhesive performance for in-situ attachment under external impact. Benefitting from the dynamic nature of the salt-bridge hydrogen bonds, the ionogel possesses impressive energy dissipation, self-healing, and recyclable properties. Notably, the prepared ionogel exhibits rate-dependent mechanical adaptivity and outstanding impact-stiffening performance with extraordinary initial modulus (∼6.3 GPa), impact strength (∼178.5 MPa), and impact toughness (∼89.6 MJ m−3) under high-speed impact (∼5200 s−1). This work offers promising biomimetic design inspirations for the future development of advanced, flexible, sustainable, and protective materials.

Magneto-thermoelastic surface waves phenomenon with voids, gravity, initial stress, and rotation under four theories

This paper addresses a significant research gap in the study of surface waves propagation in a nonhomogeneous, within a magneto-thermoviscoelastic material of higher order, initial stress, rotation, gravity effects and voids. This study provides analytical solutions for surface waves propagating through a medium consisting of a magneto-thermoelastic material with voids under the rotation, electro-magnetic field, gravity field and initial stress. The analytical solutions are derived for the displacement components, volume fraction, temperature to Stoneley and Rayleigh waves are computed numerically and presented graphically considering the external parameters impact. Furthermore, this investigates how magnetic field, voids, gravity, initial stress and fiber-reinforced parameters influence these wave phenomena. This investigation provides valuable insights into the synergistic dynamics among electric constituents, voids, Stoneley and Rayleigh waves propagation, enabling advancements in sensor technology, augmented energy harvesting methodologies, and pioneering seismic monitoring approaches. For certain materials, numerical simulations are provided and graphically displayed. The results of this study reveal several unique cases that significantly contribute to the understanding of Rayleigh and Stoneley waves propagation within this intricate material system, particularly in the presence of voids.

Incidence of anxiety after traumatic brain injury: a systematic review and meta-analysis

BackgroundTraumatic brain injury (TBI) is defined as acquired cerebral damage caused by an external mechanical impact, which has the potential to lead to transient or enduring debilitation. TBI is associated with many forms of long-lasting psychiatric conditions, including anxiety disorders. As anxiety is highly debilitating by causing impaired social functioning and decreased quality of life for the afflicted, especially in the form of anxiety disorders such as generalized anxiety disorder, certain efforts have been made to explore the factors associated with it, and one such factor is TBI.MethodsWe searched PubMed, Scopus, and Web of Science on January 26th, 2024 for observational case–control or cohort or cross-sectional studies assessing the incidence of anxiety symptoms or disorders in patients with TBI compared to healthy individuals or the same individuals if pre-TBI information regarding anxiety was available. We calculated the pooled incidence and relative risk (RR) and 95% confidence interval (95CI) using the inverse variance method. Publication bias was assessed using Eggers’s regression test. Quality assessment was performed using the Newcastle–Ottawa scale. Sub-group analyses were conducted for the type of anxiety (anxiety disorder vs anxiety symptoms), TBI severity, and type of anxiety disorders.ResultsThe incidence rate of anxiety after traumatic brain injury was 17.45% (95CI: 12.59%, 22.31%) in a total of 705,024 individuals. Moreover, TBI patients were found to be 1.9 times as likely to have anxiety compared to their non-TBI counterparts [Random effects model RR = 1.90 [1.62; 2.23], p-value < 0.0001] using a population of 569,875 TBI cases and 1,640,312 non-TBI controls. Sub-group analysis revealed TBI severity was not associated with anxiety and generalized anxiety disorder was the most common type of anxiety disorder reported post-TBI.ConclusionPatients who have experienced a TBI exhibit a significantly greater incidence of anxiety symptoms and anxiety disorders in the aftermath when compared to healthy individuals.

The impact of SRDI policy for SMEs on corporate innovation under the COVID-19: evidence from China

ABSTRACT This study focuses on small and medium-sized enterprises (SMEs) in China, and examines whether and how the SRDI (Specialized, Refinement, Differential and Innovation) policy support impacts SMEs’ innovation under the COVID-19. We find that the R&D investment and innovation outputs in SMEs supported by the SRDI policy gets significantly increased, which results from the increase in government subsidies and the implementation of digital transformation. Furthermore, the positive impact of the policy on SMEs’ innovation is more significant after the outbreak of the COVID-19. It shows that resource support from government and digital transformation can help reduce the external adverse impact of the COVID-19 on SMEs’ innovation and enhance the risk-taking and sustainable development capabilities of SMEs when the Black Swan incident occurs.

Climate Change Affects the Vulnerability of Belarusian Lakes to External Impact

Climate Change Affects the Vulnerability of Belarusian Lakes to External Impact

A Longitudinal Evaluation of Collaboration in Plastic Surgery Clinical Research.

Few dedicated, funded clinical research fellowship positions exist in plastic surgery. This study provides insights from an established clinical research fellowship, highlighting its educational impact and confirming the impact of positive institutional support and a collaborative-first approach. All research fellows within the program from 2008 to 2020 were examined during their year of employment and subsequent 2 years. Internal and external collaboration trends were assessed using PubMed affiliations. Correlation between external collaborations and research impact were examined. Research impact was characterized by publication count, journal impact factor, and journal diversity. Thirty-one research fellows were identified, with a 100% match rate. Four phases of development were identified, and a three-period cycle of productivity was noted to occur every 3 years. A shift toward more external collaborations occurred after 2016 (P = 0.008). A positive correlation was observed between external collaborations and academic output (r = 0.72, P = 0.004), journal diversity (r = 0.74, P = 0.004), and journal impact (r = 0.63, P < 0.05). Significant growth was observed in the collaborative networks (P = 0.002), publications (P = 0.003), journal diversity (P < 0.001), and research personnel (P = 0.002). As a result of our strategic decision to engage collaborators across multiple disciplines, there is discernible improvement in measurable impact, contributing to the growth of our program. Dedicating resources to foster deeper collaborations can enrich the field of plastic surgery research, recognizing that this investment fuels the cycle of productivity, offering promising returns to the future.

Информационный фактор нестабильности финансового рынка в условиях санкций недружественных стран и его нивелирование

The article is devoted to the analysis of one of the factors of financial market instability in the context of sanctions pressure on our country. The author analyzes the processes of informational and psychological manipulation of the actions of financial market participants. The opinions of scientists on problematic and controversial issues related to the destabilization of the situation in the financial market, as well as possible solutions to reduce the external impact of economic processes in the Russian Federation are presented. A measure of leveling the informational and related psychological factors of financial market instability is proposed.

Aramid-Reinforced UV Curable Adhesive Resins for Use As an Interlayer in Laminated Glass.

Colorless, transparent, and mechanically robust aramid polymers are synthesized from two diamine monomers with strong electron-withdrawing groups, using low-temperature solution condensation with diacid chloride. The aramids dissolved very well in the liquid acrylamide monomers. When N,N-dimethylacrylamide (DMA) is used as a reactive diluent, films with the desired features are produced from the hybrid aramid-DMA resins via ultraviolet (UV)curing. The hybrid films are colorless and transparent in the visible region and showed an increase in the glass transition temperature, tensile strength, and elastic modulus in proportion to the aramid content. Laminated glass is manufactured using the hybrid resin as an interlayer, which exhibits very strong adhesion between the two sheets of glass, is not easily broken by an external impact, and do not scatter fragments. Moreover, the laminated glass do not distort images and functioned very effectively in UV blocking, soundproofing, and suppressing changes in the ambient temperature. Heat treatment further improves the light transmittance and impact resistance of the laminated glass. Laminated glass specimens with various fluorescence colors are also manufactured. Aramid-reinforced films prepared using N,N-diethylacrylamide as a reactive diluent underwent thermally induced phase separation in a wet state, providing smart glass with a privacy protection function.

Shear Thickening Fluid and Sponge-Hybrid Triboelectric Nanogenerator for a Motion Sensor Array-Based Lying State Detection System.

Issues of size and power consumption in IoT devices can be addressed through triboelectricity-driven energy harvesting technology, which generates electrical signals without external power sources or batteries. This technology significantly reduces the complexity of devices, enhances installation flexibility, and minimizes power consumption. By utilizing shear thickening fluid (STF), which exhibits variable viscosity upon external impact, the sensitivity of triboelectric nanogenerator (TENG)-based sensors can be adjusted. For this study, the highest electrical outputs of STF and sponge-hybrid TENG (SSH-TENG) devices under various input forces and frequencies were generated with an open-circuit voltage (VOC) of 98 V and a short-circuit current (ISC) of 4.5 µA. The maximum power density was confirmed to be 0.853 mW/m2 at a load resistance of 30 MΩ. Additionally, a lying state detection system for use in medical settings was implemented using SSH-TENG as a hybrid triboelectric motion sensor (HTMS). Each unit of a 3 × 2 HTMS array, connected to a half-wave rectifier and 1 MΩ parallel resistor, was interfaced with an MCU. Real-time detection of the patient's condition through the HTMS array could enable the early identification of hazardous situations and alerts. The proposed HTMS continuously monitors the patient's movements, promptly identifying areas prone to pressure ulcers, thus effectively contributing to pressure ulcer prevention.

Understanding crisis perception and organizational learning – A case study of school organizations in the COVID-19 pandemic

The research investigates the organizational dynamics of learning-in-crisis (LiC) in five Hungarian education institutions in the light of the COVID-19 pandemic with a focus on digital competence building, and the influence of organizational perception of contextual factors. The path of organisation-level learning that takes place as a result of the crisis event was analysed along two factors: the extent of perceived impact and the relevance of the rare event. Results of the qualitative, interview- and observation-based research show that learning willingness is different in the face of an identical external impact, influenced by organizational and financial capacity, as well as autonomy and stakeholder maturity for change. The depth of learning is related to the strategic and cultural fit with the sought-after competence, as well as field of knowledge and the presence of parallel crises.

ANISOTROPY AND MECHANICAL CHARACTERISTICS OF ULTRA-HIGH PERFORMANCE CONCRETE AND ITS INTERPENETRATING PHASE COMPOSITE WITH TRIPLY PERIODIC MINIMAL SURFACE ARCHITECTURES

Abstract This work numerically explores the anisotropy, impact phase wave propagation, buckling resistance, and natural vibration of ultra-high performance concrete (UHPC) and UHPC-steel interpenetrating phase composite (IPC) with triply periodic minimal surfaces (TPMSs), including sheet and solid Gyroid, Primitive, Diamond, and I-WP. The experiment is conducted verifying the accuracy of the numerical model in terms of Young's modulus of polylactic acid (PLA)-based TPMS lattices and PLA-cement IPCs with TPMS cores, with the highest percent difference of 15% found for IPCs and 17% found for lattice. The results indicate that UHPC material with sheet Gyroid exhibits the least extreme anisotropy in response to the varying orientation among other lattices regardless of the change of solid density, making it the ideal candidate for construction materials. Interestingly, compared to UHPC-based TPMS lattice, IPCs possess a much smaller anisotropy and exhibit almost isotropy regardless the variation of solid density and TPMS topology, offering a free selection of TPMS type to fabricate IPCs without much care of anisotropy. The phase wave and buckling resistance of UHPC- and IPC-based beams with TPMSs nonlinearly decrease with a drop of TPMS solid density, but it is the almost linear pattern for the case of natural vibration frequency. UHPC material and IPC with sheet Gyroid lattice are found to possess the lowest phase wave velocity and exhibit the least anisotropy of wave propagation, showing it as an ideal candidate for UHPC material to suppress the destructive energy induced by the external impact.

Microseismic comprehensive evaluation method for coal burst: a case study in the Zhaolou Coal Mine

To explore the multiparameter precursor characteristics of pre- and post-coal burst. Based on a coal burst of LW 1305 in the Zhaolou Coal Mine, an early warning method combining stress‒strain curve and microseismic multiparameter is proposed. The research results show that coal burst was induced by the intrinsic static high-stress concentration and the strong external impact loading generated by fracturing of the key stratum. The precursors mainly characterize the enhancement trend of the S value, the sudden and sharp increase in the A(t) value, the continuous and abnormal decrease in the b value, the increasing absolute value of Z sharply and larger than 2, the continuous and abnormal decrease in the Qt value, and the dominant frequency moving to the low-frequency band. Essentially, many micro-fissures inside the key stratum initiated, converged and connected to form macro-fractures, which was verified by the attenuation rate of the K value. Considering the time-varying effect of the overlying stratum movement, the curves of the six parameters agree well with those of stress vs. strain, which indicates that it is reasonable to take the observed zone as a whole system to investigate the variation in the multiple parameters and fracturing of the key stratum. The research results can be applied to the monitoring, early warning and control of coal burst so that effective safety measures can be taken in real time.

Highly thermal conductivity polymer composites reinforced by BNNS/UHMWPE fabric for reliable electronic thermal protection and management

With the rapid development of 5G communication and microelectronics technology, the heat accumulation of high-power electronic devices puts forward an urgent demand for high thermal conductivity (TC) composites. However, it's still a great challenge through electrically insulating polymer to achieve good comprehensive performance of high TC, flexibility, and safety reliability. Herein, ultra-high molecular weight polyethylene (UHMWPE) fabric was coated with boron nitride nanosheets (BNNS) by dispersion and interfacial reinforcement of cellulose nanofibers (CNFs), and the BNNS/UHMWPE fabric-reinforced polymer composite (B/UF-PC) with 3D continuous thermal pathway was obtained by further composite with polydimethylsiloxane (PDMS). The continuous thermal pathways of highly aligned UHMWPE fibers in the fabric and the synergistic effect of the BNNS network enhance the out-of-plane and in-plane TC to 6.02 and 11.78 W/m K, respectively. Moreover, B/UF-PC exhibits flexible, lightweight (0.89 g/cm3), and significantly higher tensile strength (87.40 MPa) and energy absorption efficiency (98 %) than those of polymer composites, which allows it to be used in reliable electronic thermal management to prevent heat accumulation and external mechanical impact. This work provides a strategy for efficiently preparing flexible polymer composites with high TC and insulation properties.

The ion beam interceptor concept for a space station collision avoidance with space debris

Space debris poses a great threat to space stations. When a collision hazard is detected, the space station's orbit should be adjusted. An alternative approach is to apply collision avoidance measures that consist in creating an external impact on the space debris object to change its orbit and increase the miss distance slightly. Such an impact can be carried out using a ground-based or orbital laser, through the use of nano-tugs thrusters, or by placing a cloud of particles in the path of the object. This study proposes to use the plume of a thruster of an active spacecraft called an Ion Beam Interceptor. When a potential collision is detected, the interceptor undocks from the space station, approaches the space debris object and directs an ion beam, which is generated by the spacecraft's thrusters, at it. Hitting into the surface of the object, the particles of the ion beam exert a force effect on it, which leads to the required change in the orbit. After the completion of the maneuver, the interceptor returns to the space station for refueling and servicing. The objective of the study is a preliminary assessment of the feasibility and effectiveness of the proposed approach of protecting a space station from space debris impact using an active spacecraft. A mission profile of the space station protection is proposed. A series of numerical simulations are performed to determine mission parameters and fuel costs. Based on an analysis of the orbits of space objects located near the space station, the maximum angle between the orbital planes of the dangerous object and the station are determined at which it is advisable to use the Ion Beam Interceptor. The developed concept also allows to implement just-in-time collision avoidance measures for space debris objects whose orbital planes are close to the plane of the space station.

Совершенствование системы государственных закупок в целях обеспечения экономической безопасности в условиях внешнего экономического давления

The external impact of unfriendly countries on the Russian economy in order to destabilize it largely determines the strategies for ensuring the economic security of the Russian Federation in the long term. An effective tool for improving economic security can be the public procurement system, provided that the internal competition of Russian producers is maintained, as well as ensuring control over the procurement system by the state and society. The article studies the problem of the need to improve the mechanism of public procurement in order to enhance Russia’s economic security in the conditions of sanctions pressure. The relevance and novelty of the study are determined by the increasing volume of purchases made to meet state and municipal needs, the need to expand the domestic market and stimulate the development of entrepreneurship. The external impact of unfriendly countries on the Russian economy in order to destabilize it largely determines the strategies for ensuring economic security of the Russian Federation in the long term. The system of public procurement can be an effective tool to improve economic security, provided that the internal competition of Russian manufacturers is maintained and the procurement system is controlled by the state and society.

Utilization of satellite data for landslide disaster mitigation in extreme event: a case study June 18, 2016, landslide in Banjarnegara Regency, Indonesia

Abstract Understanding the characteristics of landslides produced by rainfall and soil humidity is critical for reducing the occurrence of landslides. Extreme rain, as an external impact, has been suggested to play a role in landslide development. Many people were killed in a landslide that occurred in the Banjarnegara Regency on June 18, 2016, which was unexpected because June is not Indonesia’s rainy season. El Niño and La Niña events were observed in Indonesia in 2015-2016. The initial hypothesis is that such extreme rain conditions caused this landslide. This study aims to apply an alternative approach to detecting landslides by monitoring soil moisture and rainfall with remote sensing data during extreme events. An analysis of precipitation and moisture data has been carried out before the event and is associated with the El Niño and La Niña phenomena. The findings indicate that the natural environment of Banjarnegara Regency is unique. Landslides occur even during the extreme dry season. Rain still drops, and soil moisture is high. The impact of local variables is more significant than regional conditions. They are still at risk of a landslide during the El Niño phase. During that stage, Banjarnegara Regency’s potential landslide area would continue to be observed. Monitoring needs to be carried out rapidly, with a high level of spatial and temporal resolution. It is possible to resolve it using IMERG and SMAP data.

The role of immune metabolism in skin cancers: implications for pathogenesis and therapy.

The skin is a complex organ that serves as a critical barrier against external pathogens and environmental impact. Recent advances in immunometabolism have highlighted the intricate link between cellular metabolism and immune function, particularly in the context of skin cancers. This review aims to provide a comprehensive overview of the key metabolic pathways and adaptations that occur in immune cells during homeostasis and activation, and explore how metabolic reprogramming contributes to the pathogenesis of specific skin cancers. We discuss the complex interplay between tumor cells and infiltrating immune cells, which shapes the tumor microenvironment and influences disease outcomes. The review delves into the role of various metabolic pathways, such as glycolysis, oxidative phosphorylation, and lipid metabolism, in the regulation of immune cell function and their impact on the development and progression of skin cancers. Furthermore, we examine the potential of targeting metabolic pathways as a therapeutic strategy in skin cancers and discuss the challenges and future perspectives in this rapidly evolving field. By understanding the metabolic basis of skin immune responses, we can develop novel, personalized therapies for the treatment of skin cancers, ultimately improving patient outcomes and quality of life. The insights gained from this review will contribute to the growing body of knowledge in immunometabolism and its application in the management of skin cancers, paving the way for more effective and targeted interventions in the future.

Reevaluating the linkage between trade openness and economic growth in Nigeria

This study reevaluated the linkage between trade openness and economic growth in Nigeria with data for the period of 1981 to 2022. The study employed Descriptive Statistics, Unit Root Test, Cointegration analysis, Regression Analysis (ARDL), Error Correction Model as the methods of analysis. The findings from the study showed that trade openness and external reserve impact positively and significantly on economic growth while exchange rate was found to be negative and significant. Also, findings from the error correction model showed that trade openness has a positive and insignificant impact on economic growth, external balance also has a positive significant impact on economic growth. Exchange rate on the other hand displays a negative insignificant impact on economic growth. The error correction term indicated that about 79 percent deviation in the previous year is corrected in the current year. The study therefore concluded that trade openness is a fundamental for economic growth in Nigeria and that external reserve crucial to funding of critical import necessary for domestic production. Furthermore, exchange rate of the naira showed that the economy will benefit more if the appropriate rate is prevalent in the market as this will make export to be attractive. A long run relationship was found among the variables used in the study. Based on the findings from the study we recommended that the government should engage more in international trade especially for key production inputs to boost domestic production. The government should also ensure that they maintain a healthy external reserve and ensure it is channel into the import of critical inputs. The true value of the exchange rate of the naira in relation to major currencies of the world should be targeted in order to make our exports attractive.

An integrated framework for improving green agricultural production sustainability in human-natural systems

Water scarcity, land pollution, and global warming are serious challenges and crises facing the development of sustainable or green agriculture and need to be addressed using efficient and environmentally friendly management strategies. This paper proposed an integrated framework appropriate for agricultural green total factor productivity (AGTFP) assessment coupled with microscopic and mesoscopic perspectives under water-energy-food (WEF) nexus, which generated scientific and reasonable strategies for green and low-carbon agriculture from internal core factors and peripheral environmental impacts to improve green agricultural production sustainability. Taking the Lianshui irrigation district (LID) with three sub-areas as the object, internal core factors were explored by partial least squares regression (PLSR) and the external impact path through partial least squares structural equation modeling (PLS-SEM). Results indicated that AGTFP in LID was the smallest (0.818) compared to the three sub-areas and was in a fluctuating state. Meanwhile, AGTFP which was calculated considering undesirable outputs, was closer to tangible productivity. Resource endowments and technical facilities will promote agricultural production, desirable outputs will stimulate green production, and undesirable outputs can inhibit green production. The external influence pathway was shown to be primary environment - > secondary environment - > economic aspects - > social aspects - > AGTFP. The innovative perspectives presented in this study can facilitate preferable decisions and avoid unintended consequences for human-natural systems.