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Mining-induced fracture of overburden strata is intimately related to underground water disasters in coal mining. In this work, we develop an analytical model that uses the probability integral method to calculate the subsidence of the subsurface and the overburden strata. In the developed model, according to the failure characteristics of the mining-induced strata, the horizontal deformation of the strata is expressed by the tensile rate of the elastic plate’s neutral plane to reflect the degree of fracture initiation and expansion. The distribution of the water-flowing fractured zone (WFZ) in the overburden strata is calculated by substituting the probability integral function of overburden strata movement into the equation of layer tensile rate. The panel 31071 in Peigou coal mine is taken as a case study, and the height of the water-flowing fractured zone (HWFZ) is determined by the proposed method. Conventional empirical methods and the proposed method are used to predict HWFZ in panels with mining schemes, and the results show that the model is particularly advantageous for inclined coal seam mining where the inclined mining size gradually increases and the coal seam burial depth gradually decreases. In such kind of situations, the overburden strata movement and deformation intensify and the mining fracture develops further with the progress of mining, a feature considered poorly by conventional empirical methods but well represented in the proposed method.

Energy-free cooling coatings present great potential to reduce global energy consumption, in which passive daytime radiative cooling (PDRC) without the use of additional electricity is promising. In spite of exciting progress, most of the PDRC materials are still limited by poor opto-thermal durability imposed by the unwanted surface contamination in real-world environments and complicated manufacturing processes, which hinder their practical applications. To overcome these challenges, here we develop a multi-bioinspired, hierarchically structured self-cleaning coating that imparts sustainable radiative cooling, even under harsh conditions. Our design mainly mimics the structures and functions of the Cyphochilus beetle, Saharan silver ant and lotus leaf, which synergistically results in a strong sunlight reflection, high thermal-infrared emission and robust anti-contamination. This heterogeneously integrated coating is also scalable and can be utilized on arbitrary surfaces, yielding a sub-ambient temperature drop of 13.8 °C under strong sunlight even under long-time outdoor exposure.

Subarachnoid hemorrhage (SAH) is a subtype of stroke, and early brain injury (EBI) is a contributor to its unfavorable outcome. microRNA (miRNA) is abundantly expressed in the brain and participates in brain injury. This study investigated the effect of miR-452-3p on EBI after SAH.The murine model of SAH was established. miR-452-3p expression was detected 48 h after the model establishment. Neurobehavioral function, blood-brain barrier permeability, brain water content, neuronal apoptosis, and inflammatory factors were evaluated. The cell model of SAH was induced by oxygen hemoglobin. Apoptosis rate, lactate dehydrogenase, and reactive oxygen species were detected. The targeting relationship between miR-452-3p and histone deacetylase 3 (HDAC3) was verified. The acetylation of p65 and the binding of HDAC3 to p65 were detected. The inhibitory protein of the nuclear factor κB pathway (IκBα) was detected. Suberoylanilide hydroxamic acid was injected into the SAH mice treated with miR-452-3p inhibitor.SAH mice showed upregulated miR-452-3p expression; reduced the neurological score; increased blood-brain barrier permeability, brain water content, and neuronal apoptosis; elevated pro-inflammatory factors; and reduced anti-inflammatory factors. SAH increased the apoptosis rate, lactate dehydrogenase release, and reactive oxygen species levels in oxygen-hemoglobin-treated neuron cells. Inhibition of miR-452-3p reversed the above trends. miR-452-3p targeted HDAC3. SAH upregulated p65 acetylation. miR-452-3p inhibitor promoted the binding of HDAC3 to p65, decreased p65 acetylation, and upregulated IκBα. Suberoylanilide hydroxamic acid reversed the protective effect of miR-452-3p inhibitor on SAH mice and aggravated brain injury.miR-452-3p targeted HDAC3 to inhibit the deacetylation of p65 and activate the nuclear factor κB pathway, thus aggravating EBI after SAH.

Stretchable superhydrophobic film was fabricated by casting silicone rubber polydimethylsiloxane (PDMS) on a SiO2 nanoparticle-decorated template and subsequent stripping. PDMS endowed the resulting surface with excellent flexibility and stretchability. The use of nanoparticles contributed to the sustained roughening of the surface, even under large strain, offering mechanically durable superhydrophobicity. The resulting composite film could maintain its superhydrophobicity (water contact angle ≈ 161° and sliding angle close to 0°) under a large stretching strain of up to 100% and could withstand 500 stretching–releasing cycles without losing its superhydrophobic properties. Furthermore, the obtained film was resistant to long term exposure to different pH solutions and ultraviolet light irradiation, as well as to manual destruction, sandpaper abrasion, and weight pressing.

Fault core can act as a fine groundwater seepage conduit or barrier in coal mines in China. The material properties including the granularity and clay mineral content contribute to the complexity of the fault core’s hydrogeological characteristics, especially its permeability. Seven fault core samples in Renlou coal mine were collected for clay mineral analysis and water saturation tests. The tests revealed distinct inhomogeneous particle size and porous media feature of fault core samples after water saturation for 14 days and different expansibility values ranged from 1.842 to 8.294%. The Darcy tests showed that the permeability weakening ratio increased as a power function in relation to the final expansion ratio. Finally, it was concluded that if the total mudstone thickness was greater in the entire faulted stratum section, the fault core was more impermeable and acted as a seepage barrier.

Stretchable superhydrophobic film was fabricated by casting silicone rubber polydimethylsiloxane (PDMS) on a SiO

Background: Cytoplasmic activation/proliferation-associated protein-1 (caprin-1) is a newly discovered RNA-binding protein and is now recognized as one of the putative oncogenes. This study was performed to reveal its presence in human gliomas and its oncogenic functions in human glioblastoma-derived Denver brain tumor research group 05 (DBTRG-05MG) cells. Materials and Methods: Clinical glioma samples were cumulatively collected for the identification of caprin-1 using immunoblot analysis and immunofluorescence detection. DBTRG cells transfected with caprin-1-specific small interfering RNA (siRNA) were used to verify caprin-1's oncogenic function using a real-time cell analyzer (RTCA) and scratch assay. Results: Seven of eight collected glioma samples were identified as positive for caprin-1 expression. siRNA dose-responsive inhibition of cell proliferation was observed in DBTRG cells with RTCA, and cell migration rate was significantly reduced by siRNA transfection (P < 0.05). Conclusion: The present study identified the higher expression of caprin-1 in human glioblastoma-derived DBTRG cells. Its oncogenic functions, mainly enhanced cell proliferation and promoted cell migration capacity, were also verified in these cells. This study provided fundamentals for developing caprin-1 as a therapeutic target for the treatment of gliomas.

Functionalization of synthetic suede materials with excellent superhydrophobicity can expand their application ranges. Superhydrophobic synthetic suede was obtained by coating with polydimethylsiloxane (PDMS) and octadecyltrichlorosilane (OTS). Utilizing the synthetic suede effect of the fibrous rough structures in combination with the low surface energy micro–nano rough structure on fibers resulting from PDMS and OTS, the surface was easily turned superhydrophobic with self-cleaning properties. Abrasion tests showed that the superhydrophobic synthetic suede has excellent superhydrophobic performance after more than 2000 severe abrasion tests. This research provides a facile strategy for the preparation of practical superhydrophobic synthetic suede materials.

Background: There are little data on the disease in children. This study aimed to analyze the epidemiological, clinical characteristics and drug resistance situation of culture-confirmed children TBM in Southwest of China，and hope this study will provide some recommendations to readers in clinical or related fields. Methods: We performed a retrospective study including children

RNA-binding proteins serve an essential role in post-transcriptional gene regulation. Cytoplasmic activation/proliferation-associated protein-1 (caprin-1) is an RNA-binding protein that participates in the regulation of cell cycle control-associated genes. Caprin-1 acts alone or in combination with other RNA-binding proteins, such as RasGAP SH3-domain-binding protein 1 and fragile X mental retardation protein. In the tumorigenesis process, caprin-1 primarily functions by activating cell proliferation and upregulating the expression of immune checkpoint proteins. Through the formation of stress granules, caprin-1 is also involved in the process by which tumor cells adapt to adverse conditions, which contributes to radiation and chemotherapy resistance. Given its role in various clinical malignancies, caprin-1 holds the potential to be used as a biomarker and a target for the development of novel therapeutics. The present review describes this newly identified putative oncogenic protein and its possible impact on tumorigenesis.

Preparation of chirality-defined single-wall carbon nanotubes (SWCNTs) is the top challenge in the nanotube field. In recent years, great progress has been made toward preparing single-chirality SWCNTs through both direct controlled synthesis and postsynthesis separation approaches. Accordingly, the uses of single-chirality-dominated SWCNTs for various applications have emerged as a new front in nanotube research. In this Review, we review recent progress made in the chirality-controlled synthesis of SWCNTs, including metal-catalyst-free SWCNT cloning by vapor-phase epitaxy elongation of purified single-chirality nanotube seeds, chirality-specific growth of SWCNTs on bimetallic solid alloy catalysts, chirality-controlled synthesis of SWCNTs using bottom-up synthetic strategy from carbonaceous molecular end-cap precursors, etc. Recent major progresses in postsynthesis separation of single-chirality SWCNT species, as well as methods for chirality characterization of SWCNTs, are also highlighted. Moreover, we discuss some examples where single-chirality SWCNTs have shown clear advantages over SWCNTs with broad chirality distributions. We hope this review could inspire more research on the chirality-controlled preparation of SWCNTs and equally important inspire the use of single-chirality SWCNT samples for more fundamental studies and practical applications.

Active matrix liquid crystal display (AMLCD) is the most widely used display technology nowadays. Transparent display is one of the emerging technologies to provide people with more features such as displaying images on transparent substrates and simultaneously enabling people to see the scenery behind the panel. Polymer-dispersed liquid crystal (PDLC) is a possible active matrix transparent display technology due to its high transparency, good visibility, and low power consumption. Carbon nanotubes (CNTs) with excellent mobility, high transparency, and room-temperature processing compatibility are ideal materials for the driver circuit of the PDLC display. Here, we report the monolithic integration of CNT thin-film transistor driver circuit with PDLC pixels. We studied the transmission properties of the PDLC pixels and characterized the performance of CNT thin-film transistors. Furthermore, we successfully demonstrated active matrix seven-segment PDLC displays using CNT driver transistors. Our achievements open up opportunities for future nanotube-based, flexible thin-film transparent display electronics.

BACKGROUND/AIM FAM92A1-289 is recognized as one of the newly-discovered putative oncogenes. This study was performed to reveal its oncogenic functions in human cervical carcinoma cells. MATERIALS AND METHODS The FAM92A1-289+ cell line was established with knock-in technique and selected by puromycin-resistance screening. Scratch assay, methylthiazol tetrazolium assay, colony forming assay and xenograft test were used to examine cell migration, cell proliferation, cell viability and tumor formation, respectively. RESULTS FAM92A1-289+ cells showed higher migration rate (p

Xiang-Jun Tang,1,* Kuan-Ming Huang,1,* Hui Gui,1,* Jun-Jie Wang,2 Jun-Ti Lu,1 Long-Jun Dai,1,3 Li Zhang,1 Gang Wang2 1Department of Neurosurgery, TaiHe Hospital, Hubei University of Medicine, Shiyan, 2Department of Pharmaceutics, Shanghai Eighth People’s Hospital, Jiangsu University, Shanghai, People’s Republic of China; 3Department of Surgery, University of British Columbia, Vancouver, BC, Canada *These authors contributed equally to this work Abstract: As one of the natural herbal flavonoids, myricetin has attracted much research interest, mainly owing to its remarkable anticancer properties and negligible side effects. It holds great potential to be developed as an ideal anticancer drug through improving its bioavailability. This study was performed to investigate the effects of Pluronic-based micelle encapsulation on myricetin-induced cytotoxicity and the mechanisms underlying its anticancer properties in human glioblastoma cells. Cell viability was assessed using a methylthiazol tetrazolium assay and a real-time cell analyzer. Immunoblotting and quantitative reverse transcriptase polymerase chain reaction techniques were used for determining the expression levels of related molecules in protein and mRNA. The results indicated that myricetin-induced cytotoxicity was highly potentiated by the encapsulation of myricetin. Mitochondrial apoptotic pathway was demonstrated to be involved in myricetin-induced glioblastoma cell death. The epidermal growth factor receptor (EGFR)/PI3K/Akt pathway located in the plasma membrane and cytosol and the RAS-ERK pathway located in mitochondria served as upstream and downstream targets, respectively, in myricetin-induced apoptosis. MiR-21 inhibitors interrupted the expression of EGFR, p-Akt, and K-Ras in the same fashion as myricetin-loaded mixed micelles (MYR-MCs) and miR-21 expression were dose-dependently inhibited by MYR-MCs, indicating the interaction of miR-21 with MYR-MCs. This study provided evidence supportive of further development of MYR-MC formulation for preferentially targeting mitochondria of glioblastoma cells. Keywords: myricetin, glioblastoma, EGFR, miR-21, mitochondrial apoptosis, mixed micelles, anticancer, drug delivery

Since the tumor-oriented homing capacity of mesenchymal stem cells (MSCs) was discovered, MSCs have attracted great interest in the research field of cancer therapy mainly focused on their use as carries for anticancer agents. Differing from DNA-based vectors, the use of mRNA-based antituor gene delivery benefits from readily transfection and mutagenesis-free. However, it is essential to verify if mRNA transfection interferes with MSCs' tropism and their antitumor properties. TRAIL- and PTEN-mRNAs were synthesized and studied in an in vitro model of MSC-mediated indirect co-culture with DBTRG human glioma cells. The expression of TRAIL and PTEN in transfected MSCs was verified by immunoblotting analysis, and the migration ability of MSCs after anticancer gene transfection was demonstrated using transwell co-cultures. The viability of DBTRG cells was determined with bioluminescence, live/dead staining and real time cell analyzer. An in vivo model of DBTRG cell-derived xenografted tumors was used to verify the antitumor effects of TRAIL- and PTEN-engineered MSCs. With regard to the effect of mRNA transfection on MSCs' migration toward glioma cells, an enhanced migration rate was observed with MSCs transfected with all tested mRNAs compared to non-transfected MSCs (p

Wireless communication system is more unstable than wired transmission due to the influence of transmission media. However, the micro-power transmission technology applied in the power system, the hardware parameter is more susceptible to various factors, resulting in unstable communication performance. By testing the RF parameter of transmitting and receiving signals of communication products in the laboratory, it can guide to optimize the hardware circuit and improve the communication performance of wireless transmission of micro-power, which has important reference value for hardware design

Semiconducting single-wall carbon nanotubes (SWCNTs) with long lengths are highly desirable for many applications such as thin-film transistors and circuits. Previously reported length sorting techniques usually require sophisticated instrumentation and are hard to scale up. In this paper, we report for the first time a general phenomenon of a length-dependent precipitation of surfactant-dispersed carbon nanotubes by polymers, salts, and their combinations. Polyelectrolytes such as polymethacrylate (PMAA) and polystyrene sulfonate (PSS) are found to be especially effective on cholate and deoxycholate dispersed SWCNTs. By adding PMAA to these nanotube dispersions in a stepwise fashion, we have achieved nanotube precipitation in a length-dependent order: first nanotubes with an average length of 650 nm, and then successively of 450 nm, 350 nm, and 250 nm. A similar effect of nanotube length sorting has also been observed for PSS. To demonstrate the utility of the length fractionation, the 650 nm-long nanotube fraction was subjected to an aqueous two-phase separation to obtain semiconducting enriched nanotubes. Thin-film transistors fabricated with the resulting semiconducting SWCNTs showed a carrier mobility up to 18 cm(2) (V s)(-1) and an on/off ratio up to 10(7). Our result sheds new light on the phase behavior of aqueous nanotube dispersions under high concentrations of polymers and salts, and offers a facile, low-cost, and scalable method to produce length sorted semiconducting nanotubes for macroelectronics applications.

In this paper, we report polyfluorene-separated ultra-high purity semiconducting carbon nanotube radio frequency transistors with a self-aligned T-shape gate structure. Because of the ultra-high semiconducting tube purity and self-aligned T-shape gate structure, these transistors showed an excellent direct current and radio frequency performance. In regard to the direct current characteristics, these transistors showed a transconductance up to 40 μS/μm and an excellent current saturation behavior with an output resistance greater than 200 kΩ·μm. In terms of the radio frequency characteristics, an extrinsic maximum oscillation frequency (f max) of 19 GHz was achieved, which is a record among all kinds of carbon nanotube transistors, and an extrinsic current gain cut-off frequency (f T) of 22 GHz was achieved, which is the highest among transistors based on carbon nanotube networks. Our results take the radio frequency performance of carbon nanotube transistors to a new level and can further accelerate the application of carbon nanotubes for future radio frequency electronics.

Groundwater inrush from karst collapse column (KCC) is a serious water hazard in North China. The factors determining the hydraulic conductivity of KCC remain unclear. This study analyzes the hydraulic conductivity of two KCCs from the same coal mine region and one KCC from different strata and statistically compares lithology-related data for KCCs from 11 coal mines in North China. Finally, we calculated the probability of the hydraulic conductivity of KCC and compared these calculations with field data. The results indicate that the hydraulic conductivity of KCC is mostly affected by surrounding lithology formation and closely correlated with mudstone content. When the thickness ratio of mudstone in the surrounding strata is less than 0.5, the hydraulic conductivity of KCC is more likely to be permeable. This observation of the mudstone thickness ratio provided here can be used as a criterion to qualitatively assess the hydraulic conductivity of KCCs.

Recent advances in synthesis and controlled assembly of monodisperse colloidal nanocrystals into superlattice structures have enabled their applications in optics, electronics, magnetic storage, etc. Morphology controllable silver nanoparticles exhibit numerous unfamiliar characters and have achieved extensive applications in many fields. When applied in solar cells, the silver nanoparticles are used as a catalyst in the preparation of silicon-based antireflective layers, and also the varied morphology silver nanostructures can be utilized for silver paste which makes up the electrode. During the applying process, the size and morphology of the silver nanoparticles are important factors which influence their properties. The paper introduces the morphology category and preparation method of the silver nanoparticles. The effects of the morphology of the silver nanoparticles on their properties are discussed, and the further development of their application in solar cells is prospected.

Due to their excellent electrical properties and compatibility with room-temperature deposition/printing processing, high-purity single-walled semiconducting carbon nanotubes hold great potential for macroelectronic applications such as in thin-film transistors and display back-panel electronics. However, the relative advantages and disadvantages of various nanotubes for macroelectronics remains an open issue, despite the great significance. Here in this paper, we report a comparative and systematic study of three kinds of mainstream carbon nanotubes (arc-discharge, HiPCO, CoMoCAT) separated using low-cost gel-based column chromatography for thin-film transistor applications, and high performance transistors-which satisfy the requirements for transistors used in active matrix organic light-emitting diode displays-have been achieved. We observe a trade-off between transistor mobility and on/off ratio depending on the nanotube diameter. While arc-discharge nanotubes with larger diameters lead to high device mobility, HiPCO and CoMoCAT nanotubes with smaller diameters can provide high on/off ratios (> 106) for transistors with comparable dimensions. Furthermore, we have also compared gel-based separated nanotubes with nanotubes separated using the density gradient ultracentrifuge (DGU) method, and find that gel-separated nanotubes can offer purity and thin-film transistor performance as good as DGU-separated nanotubes. Our approach can serve as the critical foundation for future carbon nanotube-based thin-film macroelectronics. Open image in new window

The ground movement laws due to wide strip mining under deep-lying seams has been studied with the experiment of similar material model, and the results of experiment could analysis qualitatively that it is feasible for wide strip mining under deep-lying seams. Taking 25 mining area of Hemei 9th mine as geologic background, the model of wide strip mining under deep seams has been made, which was used to study on the deformation of overburden and the ground movement laws. The results of experiment show that the properties and thickness of strata play a control role on the deformation, and the key strata play a core role; the deformation was dispersed with wide strip mining. When the width of strip mining and protective coal pillar are scientific and reasonable, the purpose of increasing the width of strip mining under the condition of controlling deformation could be achieved, and the entire mining area would be formed a flat subsidence basin. These achievements provide a scientific basis for solving the problem for the ground buildings protection in the conditions of wide strip mining under deep-lying seams, and that also provide some references for further studying on the method of wide strip mining under deep-lying seams.

This paper presents an investigation of the impacts of groundwater seepage on temperature distribution in the karst collapse pillar (KCP). A thermal mathematic model with groundwater seepage was proposed, and a numerical model was established to describe the impacts of groundwater seepage on the temperature distribution in the KCP. The results show that the groundwater seepage velocity improved with the increasing permeability of porous medium in the KCP. The increasing seepage velocity improves thermal convection and then improves thermal conduction in the porous medium. As a result, the heat in the deep Ordovician limestone groundwater gradually diffuses. The seepage velocity occurred differently in different locations of KCP, and the heat exchange was also different, resulting in temperature differences for different locations. This temperature divergence in the surrounding rocks can reach 5~9°C at distances less than 50 m to the KCP. These findings can be used to protect the mine from water inrush by monitoring temperature changes in the surrounding rocks of KCP.

Semiconducting single-wall carbon nanotubes are ideal semiconductors for printed electronics due to their advantageous electrical and mechanical properties, intrinsic printability in solution, and desirable stability in air. However, fully printed, large-area, high-performance, and flexible carbon nanotube active-matrix backplanes are still difficult to realize for future displays and sensing applications. Here, we report fully screen-printed active-matrix electrochromic displays employing carbon nanotube thin-film transistors. Our fully printed backplane shows high electrical performance with mobility of 3.92 ± 1.08 cm2 V–1 s–1, on–off current ratio Ion/Ioff ∼ 104, and good uniformity. The printed backplane was then monolithically integrated with an array of printed electrochromic pixels, resulting in an entirely screen-printed active-matrix electrochromic display (AMECD) with good switching characteristics, facile manufacturing, and long-term stability. Overall, our fully screen-printed AMECD is promisi...

In this paper, we report record radio frequency (RF) performance of carbon nanotube transistors based on combined use of a self-aligned T-shape gate structure, and well-aligned, high-semiconducting-purity, high-density polyfluorene-sorted semiconducting carbon nanotubes, which were deposited using dose-controlled, floating evaporative self-assembly method. These transistors show outstanding direct current (DC) performance with on-current density of 350 μA/μm, transconductance as high as 310 μS/μm, and superior current saturation with normalized output resistance greater than 100 kΩ·μm. These transistors create a record as carbon nanotube RF transistors that demonstrate both the current-gain cutoff frequency (ft) and the maximum oscillation frequency (fmax) greater than 70 GHz. Furthermore, these transistors exhibit good linearity performance with 1 dB gain compression point (P1dB) of 14 dBm and input third-order intercept point (IIP3) of 22 dBm. Our study advances state-of-the-art of carbon nanotube RF electronics, which have the potential to be made flexible and may find broad applications for signal amplification, wireless communication, and wearable/flexible electronics.

Water flow in faults made permeable by mining is potentially hazardous. We have found that (1) water flow due to this type of fault activation (FA) often occurs in the goaf near the working face (a zone of reduced stress); (2) the resistivity of the face goaf floor increases under normal conditions; and (3) electrical resistivity is obviously reduced during FA. At the Geting Coal Mine in China’s Shandong Province, the decrease in resistivity exceeded 40 Ωm when the fault began seeping. An experiment conducted at Face 2313 of the Geting Coal Mine showed that it is feasible to use electrical measurements to monitor and predict FA. Based on these conclusions, we established a monitoring criterion for FA.