The rockburst is a severe underground geological disaster, which has great damage to the workers, equipments and engineering structures. This paper aims to find a suitable way to assess the risk of ...rockburst within complicated decision making circumstances. First, plenty of literature related to the risk assessment indexes and methods of rockburst is reviewed. On account of the specific characteristics of rockburst, both quantitative and qualitative evaluation indexes are recognized in this paper. Owing to the fuzziness of human thinking and the complexity of risk assessment problems, triangular fuzzy numbers (TFNs) are advised to describe these indexes values. Meanwhile, the superiority linguistic ratings of decision makers (DMs) are used to determine the weights of indexes. After that, an extended multi-attributive border approximation area comparison (MABAC) method corresponding to TFNs is put forward to obtain the ranking results and specific risk levels of rockburst under fuzzy environment. Finally, an example of assessing the risk of rockburst in Kaiyang phosphate mine is illustrated. The rockburst proneness of four crucial areas is evaluated with the proposed method, and the ranking result is consistent with the field status. Besides, the effectiveness of this method is demonstrated with parameter and comparison analyses. The results show that the extended MABAC method is reliable and effective for evaluating the risk of rockburst, and provides references for the prevention and management of rockburst.
Shape complementarity is a biological craft for precisely binding substrates at protein–protein interfaces. An analogy to such a function can be drawn conceptually for crystalline porous solids; yet ...the manifested entities are rare in reticular chemistry. The bottleneck‐shaped pores carved out of a metal‐organic framework, Zn(MIBA)2 (aka. MAF‐stu‐13), can perfectly accommodate benzene molecules. Remarkably, its framework adapts to the optimal guest binding‐the enhanced host–guest interactions in the neck in turn minimize the guest‐guest repulsion in the pore to the extent it turns into attraction‐as demonstrated by the combined X‐ray structural and DFT computational studies. This adaptive material can be used for liquid‐phase production of ultrahigh‐purity (≥99 %) cyclohexane, achieving a balance between uptake capacity and separation selectivity and surpassing the performances of other porous and nonporous crystals reported recently (e.g. product purity 99.4 % vs. 97.5 % to date).
The bottlenecked pores in an imidazole‐containing MOF, namely MAF‐stu‐13, can adapt in shape to specifically bind benzene molecules, making it desirable for upgraded purification to yield ultrahigh‐purity (≥99 %) cyclohexane in the late stage of industrial liquid‐phase production.
ZnO is a promising high-temperature thermoelectric material because of its non-toxicity and low-cost. However, the wide band gap and low electrical conductivity lead to inferior thermoelectric ...properties. Herein, C-doping in ZnO bulk was achieved by the pyrolysis of hydrothermal surfactant TEA through a facile and speedy SPS technique. DFT calculation and experimental results show that C was incorporated into the O-site in ZnO, which reduces band gap and increases carrier concentration, thereby improving electrical conductivity and power factor. Meanwhile, the additional point defects introduced by the substitution of C/O atoms strengthen phonon scattering and decrease thermal conductivity. Benefiting from C-doping via not only tuning the electrical transport properties but also reducing the thermal conductivity, a peak ZT value of 0.024 at 773 K was achieved for Zn(O,C) bulk. It indicates that C-doping in ZnO is an effective and convenient strategy to improve thermoelectric performance.
Diamond is not only the hardest material in nature, but is also an extreme electronic material with an ultrawide bandgap, exceptional carrier mobilities, and thermal conductivity. Straining diamond ...can push such extreme figures of merit for device applications. We microfabricated single-crystalline diamond bridge structures with ~1 micrometer length by ~100 nanometer width and achieved sample-wide uniform elastic strains under uniaxial tensile loading along the 100, 101, and 111 directions at room temperature. We also demonstrated deep elastic straining of diamond microbridge arrays. The ultralarge, highly controllable elastic strains can fundamentally change the bulk band structures of diamond, including a substantial calculated bandgap reduction as much as ~2 electron volts. Our demonstration highlights the immense application potential of deep elastic strain engineering for photonics, electronics, and quantum information technologies.
The neuronal engagement of the peripheral nerve system plays a crucial role in regulating fracture healing, but how to modulate the neuronal activity to enhance fracture healing remains unexploited. ...Here it is shown that electrical stimulation (ES) directly promotes the biosynthesis and release of calcitonin gene‐related peptide (CGRP) by activating Ca2+/CaMKII/CREB signaling pathway and action potential, respectively. To accelerate rat femoral osteoporotic fracture healing which presents with decline of CGRP, soft electrodes are engineered and they are implanted at L3 and L4 dorsal root ganglions (DRGs). ES delivered at DRGs for the first two weeks after fracture increases CGRP expression in both DRGs and fracture callus. It is also identified that CGRP is indispensable for type‐H vessel formation, a biological event coupling angiogenesis and osteogenesis, contributing to ES‐enhanced osteoporotic fracture healing. This proof‐of‐concept study shows for the first time that ES at lumbar DRGs can effectively promote femoral fracture healing, offering an innovative strategy using bioelectronic device to enhance bone regeneration.
Electrical stimulation (ES) at dorsal root ganglions (DRGs) triggers calcium influx and activates the Ca2+/CaMKII/CREB signaling cascade, resulting in the transcription of calcitonin gene‐related peptide (CGRP). After synthesized in DRGs, CGRP is transported to peripheral nerve terminals and released following depolarization by ES. The released CGRP and subsequently increased type‐H vessel formation promote osteoporotic fracture healing.
Long noncoding RNAs (lncRNAs) have been reported to play pivotal roles in a variety of cancers. However, lncRNAs involved in hepatocellular carcinoma (HCC) initiation and progression remain largely ...unclear. In this study, we identified an lncRNA gradually increased during hepatocarcinogenesis (lncRNA-GIHCG) using publicly available microarray data. Our results further revealed that GIHCG is upregulated in HCC tissues in comparison with adjacent non-tumor tissues. High GIHCG expression is correlated with large tumor size, microvascular invasion, advanced BCLC stage, and poor survival of HCC patients. Functional experiments showed that GIHCG promotes HCC cells proliferation, migration, and invasion in vitro, and promotes xenografts growth and metastasis in vivo. Mechanistically, we demonstrated that GIHCG physically associates with EZH2 and the promoter of
miR-200b/a/429
, recruits EZH2 and DNMT1 to the
miR-200b/a/429
promoter regions, upregulates histone H3K27 trimethylation and DNA methylation levels on the
miR-200b/a/429
promoter, and dramatically silences miR-200b/a/429 expression. Furthermore, the biological functions of GIHCG on HCC are dependent on the silencing of miR-200b/a/429. Collectively, our results demonstrated the roles and functional mechanisms of GIHCG in HCC, and indicated GIHCG may act as a prognostic biomarker and potential therapeutic target for HCC.
Key Message
lncRNA-GIHCG is upregulated in HCC and associated with poor survival of patients.
GIHCG significantly promotes tumor growth and metastasis of HCC.
GIHCG physically associates with EZH2.
GIHCG upregulates H3K27me3 and DNA methylation levels on the
miR-200b/a/429
promoter.
GIHCG epigenetically silences miR-200b/a/429 expression.
In this study, a simple PFEM approach for analyzing large deformation problems in geotechnical practice is implemented in the commercial FEM package Abaqus. The main feature of the proposed ...Abaqus-PFEM approach lies in its capability to absorb the advantages of the functionality available in Abaqus and integrate them into PFEM with a single Python script, which leads to a considerable reduction in coding work. By utilizing the built-in functions in Abaqus to fulfil the standard incremental FEM analysis, as well as the powerful mesh-to-mesh solution mapping technique, the proposed Abaqus-PFEM approach allows for the large deformation analysis automatically running with a single Python script and requires no intervention from the user. The accuracy of the proposed Abaqus-PFEM approach is firstly validated through a simple elastic cantilever beam bending problem. Then, the performance and robustness of the proposed Abaqus-PFEM approach are further examined by three illustrative numerical examples: penetration of rigid footing, penetration of T-bar and pipeline–soil interaction problem. The numerical results demonstrate that the proposed Abaqus-PFEM approach as a powerful and easily extensible numerical tool is capable of handling large deformation and soil–structure interaction problems in geotechnical engineering, and consequently, it offers an alternative way to tackle such problems.
The height of the water-flow fracture zone (WFZ) is an important reference for designing the size of a waterproof crown pillar. Once the WFZ is connected with the sea, there will be catastrophic ...consequences, especially for undersea mining. This study suggests using a rotating forest (RoF) model to predict the height of the WFZ for the evaluation of the size of a waterproof crown pillar. To train and test the RoF model, five indicators with major influencing factors on undersea safety mining were determined, 107 field-measured mining datasets were collected, 75 (70%) datasets were used for training, and 32 (30%) datasets were used for model testing. At the same time, the random forest ensemble algorithm (RFR) and support vector machine (SVM) models were introduced for comparison and verification; in the end, the tested results were evaluated by RMSE (root-mean-square error) and R2. The comparison shows that the predicted results from the RoF model are significantly better than those from the RFR and SVM models. An importance analysis of the impact indicators shows that the mining height and depth have significant impacts on the prediction results. The development height of the WFZ in undersea safety mining was predicted via the RoF model. The predicted results via the RoF model were verified by field observations using panoramic borehole televiewers. The RoF prediction results are consistent with the observation results at all depths. Compared with the other two models, the RoF model has the smallest average absolute error at 2.87%. The results show that the RoF model can be applied to predict the height of the WFZ in undersea mining, which could be an effective way of minimizing the mineral resource waste in the study area and in other similar areas in the world under the premise of mine safety.
Retinoic acid (RA), the active metabolite of vitamin A, is one of the most important factors regulating spermatogenesis. RA activates downstream pathways through its receptors (retinoic acid receptor ...alpha RARA, retinoic acid receptor beta, and retinoic acid receptor gamma RARG) and retinoid X receptors (retinoid X receptor alpha RXRA, retinoid X receptor beta RXRB, and retinoid X receptor gamma RXRG). These receptors may serve as therapeutic targets for infertile men. However, the localization and expression of retinoid receptors in normal and infertile men were unknown. In this study, we found RARA and RARG were mostly localized in spermatocytes and round spermatids, RXRB was mainly expressed in Sertoli cells, and RXRG was expressed in most cell types in the fertile human testis. The localization of RARA, RARG, RXRB, and RXRG in men with hypospermatogenesis (HYPO) was similar to that of men with normal fertility. In addition, the messenger RNA expression levels of RARA, RARG, RXRA, RXRB, and RXRG were significantly decreased in men with Sertoli cell‐only syndrome (SCOS) and maturational arrest (MA), but not in men with HYPO. These results suggest that reduced levels of RARA, RARG, RXRB, RXRA, and RXRG are more closely associated with SCOS and MA spermatogenetic failure. These results could contribute to the development of new molecular indicators of spermatogenic dysfunction and might provide novel therapeutic targets for treating male infertility.
We found retinoic acid receptor alpha (RARA) and retinoic acid receptor gamma (RARG) were mostly localized in spermatocytes and round spermatids, retinoid X receptor beta (RXRB) was mainly expressed in Sertoli cells, and retinoic acid receptor gamma (RXRG) was expressed in most cell types in the fertile human testis. The localization of RARA, RARG, RXRB, and RXRG in men with hypospermatogenesis was similar to that of men with normal fertility.
Nanostructure engineering has been extensively applied to ZnO in an effort to improve its performance in thermoelectric material, solar cell, and nanogenerator applications. Nano-structured ZnO bulks ...are limited by their inherently low mobility caused by the high density of grain boundaries and interfaces. In this study, a hybrid micro/nano structure composed of nearly coherent grain boundaries with a low misorientation degree among the nanograins was successfully fabricated in Zn
1−
x
Al
x
O (
x
= 0, 0.01, 0.02, 0.03, 0.04 mol) bulks
via
hydrothermal synthesis and spark plasma sintering. Despite the large amount of nanograin boundaries and interfaces in the resulting material, a high carrier mobility value (50.7 cm
2
V
−1
s
−1
) was obtained in the
x
= 0.2 sample - close to the level shown by ZnO single crystals and far higher than that of its ordinary nano-structured counterparts (<15 cm
2
V
−1
s
−1
). A reduced thermal conductivity value of 2.1 W m
−1
K
−1
at 1073 K was also obtained in the micro/nano-structured
x
= 0.02 bulk due to extremely effective scattering at boundaries and interfaces also present in the nano-structured counterparts. After the simultaneous optimization of both electrical and thermal transport properties, the micro/nano-structured
x
= 0.02 sample showed a high
ZT
value (up to 0.36) at 1073 K. The proposed micro/nano-structure may also be applicable to other thermoelectric materials for further
ZT
enhancement.
We obtained a high thermoelectric figure of merit (
ZT
) in this simple ZnO by adopting a hybrid micro/nano structuring approach.
PDF
