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Currently, the coal mine fire monitoring system has achieved separate monitoring of some indicators such as the iconic gases, temperature, smoke, and flame of coal spontaneous combustion in mines.But the system has not effectively, comprehensively, and uniformly monitored the factors related to coal mine fires. In order to solve this problem, potential risk factors of coal mine fires are analyzed from two aspects: internal and external factors. A method of monitoring fire situation in different sources and areas is proposed. In terms of internal fires, monitoring is mainly carried out on goaf areas, enclosed goaf areas, and artificial natural fire observation points that are prone to fires. In terms of external fires, monitoring is mainly carried out on the mechanical and electrical chambers and their distribution points, belt conveyor systems, cables, and other aspects. A monitoring index system for coal mine fire sources and areas has been established. The system regularly collects or updates fire feature parameter data through manual or online monitoring. According to the data collection method and impact degree, fire monitoring indicators are divided into dynamic indicators, static indicators, and related indicators. The overall architecture and business process of a fire intelligent warning system is designed. The system uses a warning method based on multi index joint logical reasoning to achieve internal fire warning, and uses a multi parameter fusion warning method based on D-S evidence theory to achieve external fire warning. The on-site test results show that the fire intelligent warning system has achieved effective monitoring and warning of mine fires, with a visual display function of a coal mine fire risk warning 'one picture'. The system has a fire intelligent simulation demonstration function and a dynamic planning function for disaster avoidance routes.

Dehydrogenation of cyclohexanol to cyclohexanone is a vital step in manufacturing nylon; however, this endothermic reaction is unfavourable at low temperatures. In this work, a high-entropy oxide (Cu0.75Zn0.15Mg7.1Al1Sc1O11-HEO) was synthesized from a well-structured Cu0.75Zn0.15Mg7.1Al1Sc1(OH)20CO3 layered double hydroxide. Characterization results disclosed that Cu0.75Zn0.15Mg7.1Al1Sc1O11-HEO possesses a large specific surface area (157 m2 g−1), enhanced basicity and high Cu dispersion in the framework of HEO (74.0%). The reduced Cu0.75Zn0.15Mg7.1Al1Sc1O11-HEO catalyst was highly active and stable in the dehydrogenation of cyclohexanol compared with Cu-based catalysts prepared using binary, ternary, and quaternary mixed metal oxides. More interestingly, the conversion of cyclohexanol could be enhanced when acetone was used as the solvent and/or hydrogen acceptor. Thus, it was confirmed that the addition of acetone can enhance the yield of cyclohexanone and simultaneously result in the hydrogenation of acetone to isopropanol. [ABSTRACT FROM AUTHOR]

We analyze the initial intellectual property (IP) decisions of 336 start-ups in IP-intensive industries in China, distinguishing among patents, trademarks, and IP portfolios. Our empirical results show that the initial IP decisions of start-ups have an impact on their innovation performance. Compared with start-ups that choose trademarks or patents, start-ups that choose IP portfolios have higher financial and non-financial innovation performance. Furthermore, venture capital positively moderates the relationship between initial IP decisions and non-financial innovation performance. VC-backed start-ups that choose IP portfolios are more likely than other start-ups to achieve higher non-financial innovation performance. Finally, strategic planning also plays a role in the relationship. Among the start-ups that choose IP portfolios, those with high strategic planning gain higher non-financial innovation performance. This paper contributes to research on initial IP decisions in entrepreneurial contexts by incorporating IP portfolios to initial IP decisions and uncovering the role of initial IP decisions in innovation performance. [ABSTRACT FROM AUTHOR]

Intracerebral hemorrhage is a lethal cerebrovascular disease, and the inevitable secondary brain injury (SBI) is responsible for serious disability and death. Perfect therapeutic goal is to minimize SBI and restore neurobehavioral functions. Recently, neuroprotection is highlighted to reduce SBI, but it still faces "Neuronal survival but impaired functions" dilemma. Herein, this work further proposes a novel combinational therapeutic strategy of neuroprotection and neurogenesis toward this goal. However, appropriate therapeutic agents are rarely reported, and their discovery and development are urgently needed. Selenium participates in various physiological/pathological processes, which is hypothesized as a potential targeting molecule. To explore this effect, this work formulates an ultra-small selenium nanodot with a seleno-amino acid derived carbon dot domain and a hydrophilic PEG layer, surprisingly finding that it increases various selenoproteins levels at perihematomal region, to not only exert multiple neuroprotective roles at acute phase but promote neurogenesis and inhibit glial scar formation at recovery phase. At a safe dose, this combinational strategy effectively prevents SBI and recovers neurobehavioral functions to a normal level. Furthermore, its molecular mechanisms are revealed to broaden application scopes in other complex diseases. [ABSTRACT FROM AUTHOR]

The undesirable capacity loss after first cycle is universal among layered cathode materials, which results in the capacity and energy decay. The key to resolving this obstacle lies in understanding the effect and origin of specific active Li sites during discharge process. In this study, focusing on Ah‐level pouch cells for reliability, an ultrahigh initial Coulombic efficiency (96.1%) is achieved in an archetypical Li‐rich layered oxide material. Combining the structure and electrochemistry analysis, we demonstrate that the achievement of high‐capacity reversibility is a kinetic effect, primarily related to the sluggish Li mobility during oxygen reduction. Activating oxygen reduction through small density would induce the oxygen framework contraction, which, according to Pauli repulsion, imposes a great repulsive force to hinder the transport of tetrahedral Li. The tetrahedral Li storage upon deep oxygen reduction is experimentally visualized and, more importantly, contributes to 6% Coulombic efficiency enhancement as well as 10% energy density improvement for pouch cells, which shows great potentials breaking through the capacity and energy limitation imposed by intercalation chemistry. [ABSTRACT FROM AUTHOR]

The short-circuit ratio index (SCR) can effectively quantify the voltage support strength in traditional DC grid-connected scenarios, yet it cannot reasonably describe the voltage support strength in diverse device grid connection scenarios. This paper introduces a new calculation method of the complex short-circuit ratio index (SCR) and derives the threshold value of the complex short-circuit ratio index to enable a comprehensive quantitative assessment of grid voltage support strength across diverse device grid connection scenarios. Firstly, critical short-circuit ratio (CSCR) under different assumed conditions were derived based on the short-circuit ratio index. Secondly, the calculation method of the complex short-circuit ratio index was introduced, considering both the equivalent impedance angle of the device and the Thevenin equivalent impedance angle. This was followed by the determination of the threshold value of the complex short-circuit ratio (CSCR), enabling a precise quantitative evaluation of power grid voltage support strength in diverse device grid connection scenarios. Finally, the example analysis proves the accuracy and efficacy of the complex short-circuit ratio index in assessing the voltage support strength of diverse devices in grid-connected scenarios. [ABSTRACT FROM AUTHOR]

Pipeline leakage seriously threatens the efficient and safe gas drainage in coal mines. To achieve the accurate detection and localization of gas drainage pipeline leakages, this study proposes a gas drainage pipeline leakage detection and localization approach based on the pressure gradient method. Firstly, the basic law of gas flow in the drainage pipeline was analyzed, and a pipeline network resistance correction formula was deduced based on the pressure gradient method. Then, a drainage pipeline model was established based on the realizable k - ε turbulence model, and the pressure and flow velocity distribution during pipeline leakage under different leakage degrees, leakage locations, and pipeline negative pressures were simulated and analyzed, thus verifying the feasibility of the pipeline leakage detection and localization method. It is concluded that the positioning errors of pipeline leakage points under different leakage degrees, different leakage positions, and different pipeline negative pressures were 0.88~1.08%, 0.88~1.49%, and 0.68~0.88%, respectively. Finally, field tests were conducted in the highly located drainage roadway 8421 of the Fifth Mine of Yangquan Coal Industry Group to verify the accuracy of the proposed pipeline leakage detection and localization method, and the relative error was about 8.2%. The results show that with increased pipeline leakage hole diameters, elevated pipeline negative pressures, and closer leakage positions to the pipeline center, the relative localization error was smaller, the localization accuracy was higher, and the stability was greater. The research results could lay the foundation for the fault diagnosis and localization of coal mine gas drainage pipeline networks and provide technical support for safe and efficient coal mine gas drainage. [ABSTRACT FROM AUTHOR]

Given a bounded smooth domain $ \Omega $ in $ \mathbb{R}^2 $, we study the following anisotropic elliptic problem$\begin{cases}-\nabla(a(x) \nabla v)=a(x)\left[e^v-s \phi_1-4 \pi \alpha \delta_q-h(x)\right] & \text { in }\; \Omega, \\ v=0 & \text { on }\; \partial \Omega,\end{cases}$where $ a(x) $ is a positive smooth function, $ s>0 $ is a large parameter, $ h\in C^{0,\gamma}(\overline{\Omega}) $, $ q\in\Omega $, $ \alpha\in(-1,+\infty)\setminus\mathbb{N} $, $ \delta_q $ denotes the Dirac measure with pole at point $ q $ and $ \phi_1 $ is a positive first eigenfunction of the problem $ -\nabla\big(a(x)\nabla \phi\big) = \lambda a(x)\phi $ under Dirichlet boundary condition in $ \Omega $. We show that if $ q $ is both a local maximum point of $ \phi_1 $ and an isolated local maximum point of $ a(x)\phi_1 $, this problem has a family of solutions $ \upsilon_s $ with arbitrary $ m $ bubbles accumulating to $ q $ and the quantity $ \displaystyle{\int}_{\Omega}a(x)e^{\upsilon_s}\rightarrow8\pi(m+1+\alpha)a(q)\phi_1(q) $ as $ s\rightarrow +\infty $, which give a positive answer to the Lazer-McKenna conjecture for this case. [ABSTRACT FROM AUTHOR]

Copyright of Psyke & Logos is the property of Dansk Psykologisk Forlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Aim: The aim of this review was to determine the effectiveness of the e‐learning programs for improving the knowledge and professional practices of nursing personnel in managing pressure injuries patients. Design: Systematic review and meta‐analysis. Methods: Systematic search was done in EMBASE, SCOPUS, Cochrane library, MEDLINE, Google Scholar, ScienceDirect and Clinicaltrials.gov databases until August 2022. Meta‐analysis was carried out using random‐effects model, and the results were reported as pooled standardized mean differences (SMD), or odds ratios (OR) with 95% confidence intervals (CIs). Results: Eight studies were included in the analysis. Most of the studies had higher risk of bias. The pooled SMD for knowledge score and for the classification skill were 1.40 (95%CI: 0.45–2.35; I2 = 93.1%) and 1.75 (95%CI: 0.94–3.24; I2 = 78.3%) respectively. The pooled OR for the classification skills was 1.75 (95%CI: 0.94–3.24; I2 = 78.3%). Patient or Public Contribution: No patient or public contribution. [ABSTRACT FROM AUTHOR]

Copyright of Coal Geology & Exploration is the property of Xian Research Institute of China Coal Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shandong Medical Journal is the property of Shandong Medical Health Newspapers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Geomatics & Information Science of Wuhan University is the property of Geomatics & Information Science of Wuhan University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To study the false memory among senile normal people with high neuroticism and low neuroticism using neuropsychological scales and event-related potentials (ERPs), and to explore the effects of high neuroticism on false memory and its neuroelectrophysiological mechanism. Methods: A cross-sectional study was conducted, in which the general situation questionnaire, adult version of Eysenck personality questionnaire (EPQ) and Montreal cognitive assessment (MoCA) scale were used to establish a multi-dimensional survey in senile normal people over 60 years old from communities in Zhengzhou, and the EPQ and general situation questionnaire were used to comprehensively screen and divide the study subjects into high neuroticism group and low neuroticism group from 206 senile people. The population was matched by 1:1 according to gender, age (±2 years), and years of education (±2 years), and 40 subjects were finally enrolled for detection of electroencephalograph (EEG) components using ERPs. The Deese-Roediger-McDermott (DRM) paradigm of false memory was designed using E-prime2.0 system, and the stimulus program was presented. The EEG signals of the study subjects were recorded in real time and acquired using 64-channel Neuroscan EEG signals acquisition system. Results: High neuroticism group was evidently lower in the mean accuracy than low neuroticism group, and the difference in the mean accuracy was statistically significant (P = 0.013), but the difference in reaction time was not statistically significant. 2. The mean amplitude of EEG component N400: The difference in the main effect of N400 in the brain region was significantly different (P<0.001), and the mean amplitude of N400 was the largest in frontal region, followed by central region and parietal region successively (all P<0.05). There was no statistically significant difference in the neurotic main effect or the interaction effect of neuroticism and brain region. The latency of N400: There was no significant difference in the neurotic main effect, main effect of the brain region or the interaction effect of neuroticism and brain region. 3. The mean amplitude of EEG component LPC: The difference in the main effect of the brain region was significantly different (P<0.001), and the mean amplitude of LPC was the largest in frontal region, followed by central region and parietal region successively (all P<0.05). There was no significant difference in the neurotic main effect, neuroticism or the interaction effect of neuroticism and brain region. As to the latency of LPC, there was significant difference in the main effect of the brain region (P = 0.025), and the latency of LPC was shorter in frontal region than that in central region (P<0.05). The differences in the neurotic main effect, interaction effect of neuroticism and brain region were not statistically significant. Conclusions: High neuroticism can significantly increase the false memory of senile normal people. The EEG components N400 and LPC are potential early indicators of high neuroticism affecting false memory. High neuroticism may influence false memory by affecting the frontal cortex function. [ABSTRACT FROM AUTHOR]