circPVT1 promotes silica-induced epithelial-mesenchymal transition by modulating the miR-497-5p/TCF3 axis

Epithelial-mesenchymal transition(EMT)is a vital pathological feature of silica-induced pulmonary fibrosis.However,whether circRNA is involved in the process remains unclear.The present study aimed to investigate the role of circPVT1 in the silica-induced EMT and the underlying mechanisms.We found that an elevated expression of circPVT1 promoted EMT and enhanced the migratory capacity of silica-treated epithelial cells.The isolation of cytoplasmic and nuclear separation assay showed that circPVT1 was predominantly expressed in the cytoplasm.RNA immunoprecipitation assay and RNA pull-down experiment indicated that cytoplasmic-localized circPVT1 was capable of binding to miR-497-5p.Furthermore,we found that miR-497-5p attenuated the silica-induced EMT process by targeting transcription factor 3(TCF3),an E-cadherin transcriptional repressor,in the silica-treated epithelial cells.Collectively,these results reveal a novel role of the circPVT1/miR-497-5p/TCF3 axis in the silica-induced EMT process in lung epithelial cells.Once validated,this finding may provide a potential theoretical basis for the development of interventions and treatments for pulmonary fibrosis.

MiRNA-145-5p inhibits gastric cancer progression via the serpin family E member 1-extracellular signal-regulated kinase-1/2 axis

BACKGROUND MicroRNAs(miRNAs)regulate gene expression and play a critical role in cancer physiology.However,there is still a limited understanding of the function and regulatory mechanism of miRNAs in gastric cancer(GC).AIM To investigate the role and molecular mechanism of miRNA-145-5p(miR145-5p)in the progression of GC.METHODS Real-time polymerase chain reaction(RT-PCR)was used to detect miRNA expression in human GC tissues and cells.The ability of cancer cells to migrate and invade was assessed using wound-healing and transwell assays,respectively.Cell proliferation was measured using cell counting kit-8 and colony formation assays,and apoptosis was evaluated using flow cytometry.Expression of the epithelial-mesenchymal transition(EMT)-associated protein was determined by Western blot.Targets of miR-145-5p were predicated using bioinformatics analysis and verified using a dual-luciferase reporter system.Serpin family E member 1(SERPINE1)expression in GC tissues and cells was evaluated using RT-PCR and immunohistochemical staining.The correlation between SERPINE1 expression and overall patient survival was determined using Kaplan-Meier plot analysis.The association between SERPINE1 and GC progression was also tested.A rescue experiment of SERPINE1 overexpression was conducted to verify the relationship between this protein and miR-145-5p.The mechanism by which miR-145-5p influences GC progression was further explored by assessing tumor formation in nude mice.RESULTS GC tissues and cells had reduced miR-145-5p expression and SERPINE1 was identified as a direct target of this miRNA.Overexpression of miR-145-5p was associated with decreased GC cell proliferation,invasion,migration,and EMT,and these effects were reversed by forcing SERPINE1 expression.Kaplan-Meier plot analysis revealed that patients with higher SERPINE1 expression had a shorter survival rate than those with lower SERPINE1 expression.Nude mouse tumorigenesis experiments confirmed that miR-145-5p targets SERPINE1 to regulate extracellular signal-regulated kinase-1/2(ERK1/2).CONCLUSION This study found that miR-145-5p inhibits tumor progression and is expressed in lower amounts in patients with GC.MiR-145-5p was found to affect GC cell proliferation,migration,and invasion by negatively regulating SERPINE1 levels and controlling the ERK1/2 pathway.

Electronic Structure and Visible-Light Absorption of Transition Metals(TM=Cr,Mn, Fe, Co) and Zn-Codoped SrTiO_3: a First-Principles Study

First-principles calculations are performed on the influence of transition metal（TM=Cr, Mn, Fe, Co） as codopants on the electronic structure and visible-light absorption of Zn-doped Sr TiO_3. The calculated results show that（Zn,Mn）-codoped Sr TiO_3 requires the smallest formation energy in four codoping systems. The structures of the codoped systems display obvious lattice distortion, inducing a phase transition from cubic to rhombohedral after codoping. Some impurity Cr, Mn and Co 3d states appear below the bottom of conduction band and some Fe 3d states are located above the top of valence band, which leads to a significant narrowing of band gap after transition metal codoping. The enhancement of visible-light absorption are observed in transition metals（TM=Cr, Mn, Fe, Co） and Zn codoped Sr TiO_3 systems. The prediction calculations suggested that the（Zn,Mn）-and（Zn,Co）-codoped SrTiO_3 could be the desirable visible-light photocatalysts.

Hypersonic boundary-layer transition on a flared cone

Transition on a flared cone with zero angle of at- tack was studied in our newly established Mach 6 quiet wind tunnel （M6QT） via wall pressure measurement and flow visualization. High-frequency pressure transducers were used to measure the second-mode waves＇ amplitudes and frequencies. Using pulsed schlieren diagnostic and Rayleigh scattering technique, we got a clear evolution of the second-mode disturbances. The second-mode waves exist for a long distance, which means that the second-mode waves grow linearly in a large region. Strong Mach waves are radiated from the edge of the boundary layer. With further development, the second-mode waves reach their maximum magnitude and harmonics of the second-mode instability appear. Then the disturbances grow nonlinearly. The second modes become weak and merge with each other. Finally, the nonlinear interaction of disturbance leads to a relatively quiet zone, which further breaks down, resulting in the transition of the bound- ary layer. Our results show that transition is determined by the second mode. The quiet zone before the final breakdown is observed in flow visualization for the first time. Eventual transition requires the presence of a quiet zone generated by nonlinear interactions.

A kind of noise-induced transition to noisy chaos in stochastically perturbed dynamical system

We investigate a kind of noise-induced transition to noisy chaos in dynamical systems. Due to similar phenomenological structures of stable hyperbolic attractors excited by various physical realizations from a given stationary random process, a specific Poincar6 map is established for stochastically perturbed quasi-Hamiltonian system. Based on this kind of map, various point sets in the Poincar6＇s cross-section and dynamical transitions can be analyzed. Results from the customary Duffing oscillator show that, the point sets in the Poincare＇s global cross-section will be highly compressed in one direction, and extend slowly along the deterministic period-doubling bifurcation trail in another direction when the strength of the harmonic excitation is fixed while the strength of the stochastic excitation is slowly increased. This kind of transition is called the noise-induced point-overspreading route to noisy chaos.

X-ray diffraction study of effect of deposition conditions on α-β phase transition and stress evolution in sputter-deposited W coatings

Pure W and W-Cu-W trilayer coatings were deposited on an Fe substrate by d.c. magnetron sputtering. The α-β phase evolution, intragranular stress evolution in sputter-deposited W layer were investigated by x-ray diffraction. They are directly related to the film microstructure, density and adhesion. Therefore, control of the film stress and phase component transition is essential for its applications. The phase component transition from β-W to α-W and intragranular stress evolution from tensile to compressive strongly depend on the deposition parameters and can be induced by lowering Ar pressure and rising target power. The compressively stressed films with α-W phase have a dense microstructure and high adhesion to Fe substrate.

THE STUDY ON COLOURING MECHANISM OF THE COLOUR-TRANSITION GLAZE

The colour-transition glazed brick has been made under suitable conditions and the expected result has been-obtained.The chemical compositions of the glaze have been given. The structures of Na_2O(K_2O)-CaO(MgO)-Al_2O_3 -SiO_2 system,parent glaze and colour-transition glaze have been invesitigated by SME,Visible spec- trum,IR spectrum and Raman spectrum.A brief exp- lanation to colouring mechanism of colour-transi- tion glaze was given in accordance with theory of optical absorption and scattering. For all specimens,liquid phase separation structures were observed generally be SEM and acomparison between parent glaze and colour-transi- tion glaze was made by Visible specta.Hence an inference can be drawn from these results that the liquid phase droplets contain Nd^(3+),Pr^(3+) ions, which cause coloration selective absorbing and scattering of incident light waves.

Doping dependent metal to insulator transition in the(Bi,Pb)-2212 system:The evolution of structural and electronic properties with europium substitution

The present work investigates the effect of europium substitution on the （Bi, Pb）-2212 system in the concentration range 0.5 ≤ x ≤1.0. Phase analysis and lattice parameter calculations on the powder diffraction data and the elemental analysis of EDX show that the Eu atoms are successfully substituted into the （Bi, Pb）-2212 system. Resistivity measurements （64-300 K） reveal that the system exhibits superconductivity at x ≤ 0.5 and semiconductivity at x 〉 0.5. With the complete suppression of superconductivity which is known to be a quasi-two dimensional phenomenon in these materials, a metal to insulator transition takes place at x = 0.6 and the predominant conduction mechanism is found to be variable range hopping between localized states, resulting in macroscopic semiconducting behaviour. The results of electrical and structural properties of the doped （Bi, Pb）-2212 compounds suggest that the decrease of charge carrier concentration and the induced structural disorder are the more effective and dominant mechanisms in the origin of the metal to insulator transition and suppression of superconductivity due to Eu substitution at its Sr site.

North slope transition zone of Songnan-Baodao sag in Qiongdongnan Basin and its control on medium and large gas fields,South China Sea

Based on analysis of newly collected 3D seismic and drilled well data,the geological structure and fault system of Baodao sag have been systematically examined to figure out characteristics of the transition fault terrace belt and its control on the formation of natural gas reservoirs.The research results show that the Baodao sag has the northern fault terrace belt,central depression belt and southern slope belt developed,among them,the northern fault terrace belt consists of multiple transition fault terrace belts such as Baodao B,A and C from west to east which control the source rocks,traps,reservoirs,oil and gas migration and hydrocarbon enrichment in the Baodao sag.The activity of the main fault of the transition belt in the sedimentary period of Yacheng Formation in the Early Oligocene controlled the hydrocarbon generation kitchen and hydrocarbon generation potential.From west to east,getting closer to the provenance,the transition belt increased in activity strength,thickness of source rock and scale of delta,and had multiple hydrocarbon generation depressions developed.The main fault had local compression under the background of tension and torsion,giving rise to composite traps under the background of large nose structure,and the Baodao A and Baodao C traps to the east are larger than Baodao B trap.Multiple fault terraces controlled the material source input from the uplift area to form large delta sand bodies,and the synthetic transition belt of the west and middle sections and the gentle slope of the east section of the F12 fault in the Baodao A transition belt controlled the input of two major material sources,giving rise to a number of delta lobes in the west and east branches.The large structural ridge formed under the control of the main fault close to the hydrocarbon generation center allows efficient migration and accumulation of oil and gas.The combination mode and active time of the main faults matched well with the natural gas charging period,resulting in the hydrocarbon gas enrichment.Baodao A transition belt is adjacent to Baodao 27,25 and 21 lows,where large braided river delta deposits supplied by Shenhu uplift provenance develop,and it is characterized by large structural ridges allowing high efficient hydrocarbon accumulation,parallel combination of main faults and early cessation of faulting activity,so it is a favorable area for hydrocarbon gas accumulation.Thick high-quality gas reservoirs have been revealed through drilling,leading to the discovery of the first large-scale gas field in Baodo 21-1 of Baodao sag.This discovery also confirms that the north transition zone of Songnan-Baodao sag has good reservoir forming conditions,and the transition fault terrace belt has great exploration potential eastward.

Correlation of SphK1, FAK, Musashi 1 and CA199 expression with angiogenesis and epithelial-mesenchymal transition in surgically removed colon cancer lesions

Objective: To investigate the correlation of SphK1, FAK, Musashi 1 and CA199 expression with angiogenesis and epithelial-mesenchymal transition in surgically removed colon cancer lesions. Methods: A total of 60 patients with colon cancer who underwent radical operation in our hospital between August 2015 and August 2017 were selected, intraoperative colon cancer tissue samples were collected as colon cancer group, and normal tissue specimens adjacent to carcinoma were collected as adjacent tissue group. Fluorescence quantitative PCR was adopted to determine the expression levels of SphK1, FAK, Musashi 1, CA199 as well as the genes related to angiogenesis and epithelial-mesenchymal transition in colon tissues with different properties. Results: SphK1, FAK, Musashi 1 and CA199 mRNA expression in colon cancer group were higher than those in adjacent tissue group;angiogenesis-related genes ANGPTL4, Apelin-13, DLL1, VEGF and HIF-α mRNA expression were higher than those in adjacent tissue group whereas TSP-1 mRNA expression was lower than that in adjacent tissue group;epithelial-mesenchymal transition-related gene E-cadherin mRNA expression was lower than that in adjacent tissue group whereas Vimentin, N-cadherin, Twist and Snail mRNA expression were higher than those in adjacent tissue group. Correlation analysis showed that the SphK1, FAK, Musashi 1 and CA199 expression in colon cancer tissues were directly correlated with the angiogenesis genes and epithelial-mesenchymal transition genes. Conclusion: SphK1, FAK, Musashi 1 and CA199 genes are abnormally expressed in colon cancer tissues and their expression levels are directly correlated with tumor angiogenesis and epithelial-mesenchymal transition process.

Tuning the particle size,physical properties,and photocatalytic activity of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio

This study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)O.The material characterizations were carried out using x-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive x-ray spectroscopy(EDX),Brunauer–Emmett–Teller(BET)surface area,Fourier transform infrared(FTIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),UV-vis absorption,and photoluminescence(PL).The results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size increase.This change is also observed in the Raman scattering and FTIR spectra with the increase in the vibration frequency of the[PO_(4)]group.The compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding energy.The photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light irradiation.This is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample.

二氧四胺大环配合物紫外-可见吸收谱

测量了二氧四胺大环配体及其 Cu( ) ,Co( ) ,Ni( )配合物的紫外 -可见吸收光谱 ,对谱带作了归属 ,发现配合物的 d- d跃迁波长满足λNi<λCo<λCu,并对其做了解释 .

黄土-红粘土记录的构造尺度气候变化

晚新生代约5Ma以来，全球气候系统发生了一系列的重要转型，地球从单极（南极）常年有冰变为两极常年有冰，新生代从“温室”转为“冰室”的漫长历程至此完成。中国连续的黄土-红粘土沉积覆盖了约8—7Ma以来的时段，提供了完整的Pliocene-Pleistocene转型时期的陆相古气候记录，是研究晚新生代构造尺度气候变化和转型的重要记录。黄土-红粘土记录表明，其构造尺度变化既在相当程度上反映了晚中新世-上新世以来的全球变冷信号和Plio／Pleistocene转折、Mid．Pleistocene转折等重要构造事件，同时也对重要的区域构造和环境演化过程有显著的响应。今后需要通过对黄土-红粘土记录的研究，就上新世-更新世一系列的转型过程中重要气候系统成员的变化特征、高低纬气候系统相互作用特征以及转型机制等第四纪气候变化的根本问题作出有特色的回答。

EDA复合物介导的光催化合成全氟取代异喹啉二酮

本文开发了一个由电子供体受体(EDA)复合物介导、可见光诱导合成全氟取代异喹啉二酮骨架的反应。该反应无需过渡金属光敏剂催化,反应条件温和,具有绿色环保、清洁高效的特点。

Anomalous spin Josephson effect in spin superconductors

The spin superconductor state is the spin-polarized triplet exciton condensate,which can be viewed as a counterpart of the charge superconductor state.As an analogy of the charge Josephson effect,the spin Josephson effect can be generated in the spin superconductor/normal metal/spin superconductor junctions.Here we study the spin supercurrent in the Josephson junctions consisting of two spin superconductors with noncollinear spin polarizations.For the Josephson junctions with out-of-plane spin polarizations,the possibleπ-state spin supercurrent appears due to the Fermi momentum-splitting Andreev-like reflections at the normal metal/spin superconductor interfaces.For the Josephson junctions with in-plane spin polarizations,the anomalous spin supercurrent appears and is driven by the misorientation angle of the in-plane polarizations.The symmetry analysis shows that the appearance of the anomalous spin Josephson current is possible when the combined symmetry of the spin rotation and the time reversal is broken.

U(1)Lμ-Lτ breaking phase transition, muon g–2, dark matter, collider, and gravitational wave

Combining the dark matter and muon g-2 anomaly,we study the U(1)Lμ-Lτbreaking phase transition,gravitational wave spectra,and direct detection at the LHC in an extra U(1)Lμ-Lτgauge symmetry extension of the standard model.The new fields include vector-like leptons(E1,E2,N),the U(1)Lμ-Lτbreaking scalar S,and the gauge boson Z’,as well as the dark matter candidate XI and its heavy partner XR.A joint explanation of the dark matter relic density and muon g-2 anomaly excludes the region where both min(mE1,mE2,mN,mXR)and min(mZ’,mS)are much larger than mXI.In the parameter space accommodating the DM relic density and muon g-2 anomaly,the model can achieve a first-order U(1)Lμ-Lτbreaking phase transition,whose strength is sensitive to the parameters of the Higgs potential.The corresponding gravitational wave spectra can reach the sensitivity of UDECIGO.In addition,the direct searches at the LHC impose stringent bounds on the mass spectra of the vector-like leptons and dark matter.

过渡金属与新型硝基酚臂式氮杂18-冠-6配位性能的研究

合成并表征了1,10-二氧-4,7,13,16-四氮杂18-冠-6(1)母体及其四取代硝基酚臂式衍生物(2)。在H2O-DMSO(V/V=1/4)混合溶剂中用UV-Vis光谱法对冠醚2与H+、Mn2+、Co2+、Ni2+、Cu2+、Zn2+、Cd2+和Hg2+离子的键合行为进行了研究,并测定了配位稳定常数。结果表明,当冠醚2处在pH值小于7.96的体系中时,其仅有316nm左右的吸收峰;当pH值大于7.96时,在400nm左右产生新的吸收峰,而且其峰位波长和强度随溶液的碱性增强逐渐增大。在冠醚2体系中有过渡金属离子存在时,冠醚在400nm左右的吸收峰发生紫移,强度也有显著的变化,证实了在大于一定pH值的环境中过渡金属与冠醚2可形成配合物。稳定常数的测定表明,冠醚2对Mn2+离子有明显的选择性,与Co2+、Ni2+、Cu2+、Zn2+的配位能力依次有所增强,与Cd2+和Hg2+离子的配位稳定性较小。

噻吩硫掺杂氮化碳促进n-π^(*)电子跃迁增强光催化活性

光催化技术是一种绿色的化学技术,它可以利用取之不尽的太阳能来降解有毒污染物或者分解水产生氢气等.毋庸置疑,这项技术的核心是半导体光催化剂,在太阳光的照射下,半导体产生电子-空穴对,分别迁移至表面参与氧化还原反应.然而,半导体光催化剂中电子和空穴易快速复合以及其对太阳能中占主导的可见光利用率较低阻碍了其在实际中的应用.因此,解决这些问题,实现光催化技术的产业化应用,成为更多研究者关注的焦点.石墨相碳氮化物(g-C_(3)N_(4))作为一种新型的聚合物半导体,因其来源丰富、合成简便、化学和物理性质稳定以及能带结构可调而吸引了研究人员的兴趣,但是它仍然存在上述问题.目前,提高g-C_(3)N_(4)光催化性能的方法大致有以下三种:改变形貌或进行元素掺杂以调节能带结构,与其他半导体复合构建异质结构来加速光生载流子的迁移,拓展可见光吸收范围.g-C_(3)N_(4)的光催化活性主要受自身骨架结构中的π电子传输影响,但π电子只能在波长<420 nm的高能量光下才能被激发.研究可知,设计N原子上孤对电子暴露于平面外部的氮化碳结构,在可见光激发下即可产生n-π^(*)电子跃迁,获得显著增强的光吸收能力,从而提升光催化活性.然而,这些研究仅关注了g-C_(3)N_(4)中N原子上孤对电子形成的n-π^(*)跃迁,并未研究外来材料杂原子上的孤对电子是否具有相似的作用.因此,利用合适的、含孤对电子的材料来修饰g-C_(3)N_(4),也有可能获得类似的n-π^(*)电子跃迁.本工作以含芳香环结构的噻吩基丙二酸(ThA)与尿素作为前驱体,通过热聚合方法合成了具有高效n-π^(*)电子跃迁的CN-ThAx材料,并在可见光条件下,通过降解双酚A以及分解水实验测试其光催化性能.采用漫反射光谱(DRS)、光致发光光谱(PL)、理论计算、扫描电镜(SEM)、透射电镜(TEM)和X射线光电子能谱(XPS)等表征手段分析了催化剂的光学性质、微观形貌和结构特征.通过DRS、PL和理论计算分析可知,n-π^(*)电子跃迁可提升CN-ThAx在450-550 nm区域的光学吸收,增强材料对可见光利用效率.SEM和TEM结果显示,ThA修饰并未改变g-C_(3)N_(4)的形貌,结合XPS结果可知,n-π^(*)电子跃迁不是由g-C_(3)N_(4)中N原子的孤对电子引起的,而是由ThA中S元素的孤对电子引起的.光催化性能测试结果也表明,ThA修饰后的CN-ThAx在可见光下具有更优的光催化性能.因此,本研究为设计具有较高可见光利用率的氮化碳材料提供了新思路.

Scaling law of hydrogen evolution reaction for InSe monolayer with 3d transition metals doping and strain engineering

Recently, two dimensional In Se attracts great attentions as potential hydrogen production photocatalysts.Here, comprehensive investigations on the hydrogen evolution reaction activity of In Se monolayer with3 d transition metal doping and biaxial strain were performed based on the density functional theory.Transition metal dopants significantly increase the bonding strength between H and Se, and then adjust the hydrogen adsorption free energy to 0.02 e V by Zn doping. The enhanced hydrogen evolution reaction activity results from less electron occupying H 1 s-Se 4 pzanti-bonding states, which is well correlated with the pzband center level. Importantly, the universal scalling law was proposed to descript the evolution of hydrogen adsorption free energy including both doping and strain effects. Moreover, with appropriate band alignment, optical absorption, and carriers separation ability, Zn doped In Se monolayer is considered as a promising candidate of visible-light photocatalyst for hydrogen production.

LncRNA cancer susceptibility 20 regulates the metastasis of human gastric cancer cells via the miR-143-5p/MEMO1 molecular axis

BACKGROUND Gastric cancer(GC)is considered as one of the most widespread malignancies.Emerging evidence has shown that lncRNAs can function as important oncogenes or tumor suppressors during GC progression.AIM To investigate the effect and mechanism of lncRNA cancer susceptibility 20(CASC20)in the proliferation and metastasis of GC cells.METHODS Data mining and clinical samples were used to evaluate the expression of CASC20 in GC and adjacent tissues.CASC20 was down-regulated in GC cells by shortinterfering RNA.Cell proliferation was evaluated by CCK-8 assay,and cell migration and invasion were detected by wound healing and Transwell assays.The expressions of proteins related to epithelial-mesenchymal transition were detected by western blot assay.RESULTS The expression of CASC20 was increased in GC tumor tissues and various GC cell lines.High CASC20 expression was correlated with a high risk of lymphatic metastasis and poor prognosis in GC patients.In vitro assays showed that silencing CASC20 reduced cell proliferation,migration,and invasion in GC cells.Mechanistic studies revealed that CASC20 exhibits oncogenic functions by regulating MEMO1 expression through competitive endogenous binding to miR-143-5p,leading to induction of epithelial-mesenchymal transition.CONCLUSION Our findings indicate that CASC20 serves as a tumor promoter by regulating metastasis in GC via the miR-143-5p/MEMO1 axis.CASC20 may be a potential therapeutic target for GC.