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Vortex electromagnetic waves (VEMWs) carrying orbital angular momentum (OAM) are promising to benefit the higher degree of freedom for inverse synthetic aperture radar (ISAR) imaging on account of their helical wavefront. For high‐speed targets, the ‘stop and go’ hypothesis is no longer valid. Thus, the intrapulse movement of the target will cause the broadening and shift of the one‐dimensional range profile and the blurring of the OAM eigenvalues coupling azimuth. This contribution proposes a high‐speed target imaging method for the VEMW ISAR. First, an OAM‐based ISAR imaging model for high‐speed targets is derived and the echo characteristics are analysed. Subsequently, in order to effectively estimate the ratio of the echo to correct the imaging result, an estimation method that takes into account the calculation speed and accuracy is proposed. On this basis, the target velocity distribution obtained under multiple echoes is analysed to improve the accuracy of the results. Finally, the range profile and azimuthal profile are reconstructed. Compared with the existing vortex electromagnetic imaging algorithm, the proposed method can effectively eliminate the influence of high‐speed motion on the range and azimuth profile. This work provides suggestions for the development of EM vortex ISAR imaging technology.

Cerebral vasospasm (CVS) is a frequent and serious neurosurgical complication, without sufficient therapy. This retrospective study was performed to analyze if nimodipine can improve prognosis and reduce ischaemia secondary to delayed CVS after intracranial tumour surgery. A retrospective review was performed over the years 2011 to 2012 for patients with an anterior cranial fossa tumour and underwent intracranial tumour surgery. The surgical field was soaked with nimodipine solution or normal saline. Transcranial Doppler ultrasonography was used to measure velocity in the middle cerebral artery (MCA) and the distal extracranial internal carotid artery (eICA). Follow-up was performed using the Glasgow Outcome Scale (GOS) after discharge. There were 94 patients that met the inclusion criteria. They included 50 males and 44 females, with a mean age of 49.6 years. In the nimodipine group, CVS occurred in 13 patients; 9 patients had CVS between 4 and 7 days, and 4 had CVS between 8 and 14 days. In the normal saline group, 19 patients had CVS, 3 presented with CVS within 3 days, 11 between 4-7 days and 5 between 8-14 days. A significant difference in the occurrence of CVS was observed between the two groups. Preoperative and postoperative the MCA velocities were compared, revealing a significant change in the normal saline group but not in the nimodipine group. Nimodipine markedly improves prognosis and significantly reduces ischaemia secondary to delayed CVS after intracranial tumour surgery, as well as the risks of mortality and morbidity.

Based on the ‘resource curse’ theory, this study uses panel data for 256 prefecture‐level cities in China from 2003 to 2016 to test the relationship and mechanism between natural resource dependence and economic development. The panel model and instrumental variable regression results show that natural resources generally promote economic development, but for 109 resource‐based cities, the influence of natural resources on economic development seems quite different. The panel threshold model shows that in the resource‐based cities, (i) resources have a ‘blessing effect’ on economic development during economic prosperity (GDP growth rate is greater than 12.1 per cent); (ii) the relationship is not statistically significant when the GDP growth rate is between 5 per cent and 12.1 per cent; and (iii) when the GDP growth rate is lower than 5 per cent, natural resources have a ‘curse effect’ on economic development. Furthermore, the results of the mediation effect model show that the mediation effect of industrial diversification on the relationship between resource dependence and economic development suppresses the promotion of natural resource on economy. An excessive concentration of resource industries has a crowding‐out effect on non‐resource industries in resource‐based cities, which reduces the level of industrial diversification and is not conducive to economic development.

While hundreds of consistently altered metabolic genes had been identified in hepatocellular carcinoma (HCC), the prognostic role of them remains to be further elucidated. Messenger RNA expression profiles and clinicopathological data were downloaded from The Cancer Genome Atlas-Liver Hepatocellular Carcinoma and GSE14520 data set from the Gene Expression Omnibus database. Univariate Cox regression analysis and lasso Cox regression model established a novel four-gene metabolic signature (including acetyl-CoA acetyltransferase 1, glutamic-oxaloacetic transaminase 2, phosphatidylserine synthase 2, and uridine-cytidine kinase 2) for HCC prognosis prediction. Patients in the high-risk group shown significantly poorer survival than patients in the low-risk group. The signature was significantly correlated with other negative prognostic factors such as higher α-fetoprotein. The signature was found to be an independent prognostic factor for HCC survival. Nomogram including the signature shown some clinical net benefit for overall survival prediction. Furthermore, gene set enrichment analyses revealed several significantly enriched pathways, which might help explain the underlying mechanisms. Our study identified a novel robust four-gene metabolic signature for HCC prognosis prediction. The signature might reflect the dysregulated metabolic microenvironment and provided potential biomarkers for metabolic therapy and treatment response prediction in HCC.

Cytochrome P450 1A1 (CYP1A1) is abundant in the kidney, liver, and intestine and is involved in the phase I metabolism of numerous endogenous and exogenous compounds. Therefore, exploring the regulatory mechanism of its basal expression in humans is particularly important to understand the bioactivation of several procarcinogens to their carcinogenic derivatives. Site-specific mutagenesis and deletion of the transcription factor binding site determined the core cis-acting elements in the human CYP1A1 proximal and distal promoter regions. The proximal promoter region [overlapping xenobiotic-responsive element (XRE) and GC box sequences] determined the basal expression of CYP1A1. In human hepatocellular carcinoma cells (HepG2) with aryl hydrocarbon receptor (AhR) or specificity protein 1 (Sp1) knockdown, we confirmed that AhR and Sp1 are involved in basal CYP1A1 expression. In HepG2 cells overexpressing either AhR or Sp1, AhR determined the proximal transactivation of basal CYP1A1 expression. Via DNA affinity precipitation assays and ChIP, we found that AhR bound to the promoter and recruited Sp1 to transactivate CYP1A1 expression. The coordinated interaction between Sp1 and AhR was identified to be DNA mediated. Our work revealed a basal regulatory mechanism of an interesting human gene by which AhR interacts with Sp1 through DNA and recruits Sp1 to regulate basal CYP1A1 expression.

Background MicroRNAs (miRNAs) function as tumor promoting or tumor suppressing factors in many cancers. MiR-520b contributes to progression in head-neck and liver cancers, spinal osteosarcoma, and glioma; however, the association of miR-520b with lung cancer progression remains unknown. In this investigation, we explore the effect of miR-520b targeting HDAC4 on lung cancer growth. Methods The regulation of miR-520b or its inhibitor on HDAC4 expression was analyzed using Western blot analysis. After treatment of miR-520b or its inhibitor, miR-520b and HDAC4 levels were examined using quantitative real time-PCR. The modulation of miR-520b on HDAC4 was investigated by luciferase reporter gene assay. Cell proliferation evaluation was performed using colony formation and methyl-thiazolyl-tetrazolium assays. The correlation between miR-520b and HDAC4 in human clinical samples was verified using Pearson's correlation coefficient. Results An obvious decrease in HDAC4 expression was observed in lung cancer A549 cells treated with different doses of miR-520b. The miR-520b inhibitor enhanced HDAC4 expression in lung cancer cells. Bioinformatics predicted the targeting of miR-520b on HDAC4. MiR-520b directly targeted the 3' untranslated region of HDAC4. The introduction of miR-520b obviously inhibited cell proliferation in vitro. Anti-miR-520b was capable of accelerating lung cancer cell proliferation; however, HDAC4 knockdown destroyed anti-miR-520b-induced cell proliferation. Finally, a negative correlation between miR-520b and HDAC4 was observed in clinical human lung cancer samples. Conclusion MiR-520b decreases HDAC4 expression to control cell proliferation in lung cancer.

One natural p-terphenyl glycoside, gliocladinin C, and two furano-polyene derivatives, chaetominins A and B, were isolated from potato endophytic fungus Chaetomium subaffine. The absolute configurations of these compounds were elucidated by HR-ESI-MS, NMR, the DP4+ probabilities and electronic circular dichroism (ECD) spectra. Furthermore, gliocladinin C and chaetominin A showed cytotoxic activity against two selected human tumor cell lines (Hep-2 and HepG-2).

A coupling model for a compound quartz crystal resonator (QCR) system, consisting of a QCR under the thickness-shear mode (TSM) vibrations and surface micro-beam arrays immersed in liquid, is developed using the modified couple stress theory and the Hamilton's variational principle. Couple stresses are included in both governing equations of micro-beams and the quartz crystal plate. Incorporating the boundary conditions, a set of homogeneous equations is numerically solved to get the frequency shift caused by micro-beams for different material parameters, such as Young's modulus and material characteristic length. The normalized beam deflections are plotted and discussed. Influence of couple stresses of both micro-beams and QCR together with their interaction on frequency shift is discussed in detail. The obtained results are useful in measuring geometrical and physical properties of micro-beams using plate-like acoustic wave sensors.

Summary Recent advances in financial econometrics have allowed for the construction of efficient ex post measures of daily volatility. This paper investigates the importance of instability in models of realised volatility and their corresponding forecasts. Testing for model instability is conducted with a subsampling method. We show that removing structurally unstable data of a short duration has a negligible impact on the accuracy of conditional mean forecasts of volatility. In contrast, it does provide a substantial improvement in a model's forecast density of volatility. In addition, the forecasting performance improves, often dramatically, when we evaluate models on structurally stable data.

A new I2/CuO-promoted one-pot tandem strategy is presented for the synthesis of imidazo[1,2-a]pyridine derivatives which has a broad scope of substrates, including aryl methyl ketones, heteroaryl ketones, α,β-unsaturated methyl ketones, β-ketone esters, and substituted 2-aminopyridines.

In the present study, the porcine zona pellucida (ZP)-3alpha eukaryotic expression vector pVAX1-pZP3alpha was constructed by genetic recombinant technology, then the recombinant plasmid was encapsulated in nanoparticles with chitosan, and the imaging of chitosan/pVAX1-pZP3alpha nanoparticles by Atomic Force Microscope (AFM) was processed. Feeding mouse with those microencapsulation by gastric larvae, and after 5 days, detecting its expression in mouse intestine by RT-PCR and indirect immunofluorescence (IIF). Results show that the porcine ZP-3alpha eukaryotic expression vector pVAX1-pZP3alpha had been constructed correctly, and the chitosan-DNA expressing ZP microencapsulation was prepared successfully. After 5 days of feeding mouse, the transcription and expression of those DNA vaccines were found in mouse alvine chorion. The preparation of chitosan/pVAX1-pZP3alpha plasmid DNA nanoparticles and its expression in mice will help to investigate the feasibility of ZP DNA vaccine to induce oviduct local mucosal immunity against ZP to block the fertilization without causing ovarian dysfunction, which will provide new ideas and ways for research and exploiting more effective, more convenient oral contraceptive vaccines.