Preserved amplitude migration based on the one way wave equation in the angle domain

Traditional pre-stack depth migration can only provide subsurface structural information. However, simple structure information is insufficient for petroleum exploration which also needs amplitude information proportional to reflection coefficients. In recent years, pre-stack depth migration algorithms which preserve amplitudes and based on the one- way wave equation have been developed. Using the method in the shot domain requires a deconvolution imaging condition which produces some instability in areas with complicated structure and dramatic lateral variation in velocity. Depth migration with preserved amplitude based on the angle domain can overcome the instability of the one-way wave migration imaging condition with preserved amplitude. It can also offer provide velocity analysis in the angle domain of common imaging point gathers. In this paper, based on the foundation of the one-way wave continuation operator with preserved amplitude, we realized the preserved amplitude prestack depth migration in the angle domain. Models and real data validate the accuracy of the method.

Effect of atomic structure on migration characteristic and solute segregation of ordered domain interfaces formed in Ni_(75)Al_xV_(25-x)

Based on the microscopic phase-field model, ordered domain interfaces formed between D022 （Ni3V） phases along [001] direction in Ni75AlxV25-x alloys were simulated, and the effects of atomic structure on the migration characteristic and solute segregation of interfaces were studied. It is found that the migration ability is related to the atomic structure of interfaces, and three kinds of interfaces can migrate except the interface （001）//（002） which has the characteristic of L12 （Ni3Al） structure. V atoms jump to the nearest neighbor site and substitute for Ni, and vice versa. Because of the site selectivity behaviors of jumping atoms, the number of jumping atoms during the migration is the least and the jumping distance of atoms is the shortest among all possible modes, and the atomic structures of interfaces are unchanged before and after the migration. The preferences and degree of segregation or depletion of alloy elements are also related to the atomic structure of interface.

Viscoacoustic prestack reverse time migration based onthe optimal time-space domain high-order finite-difference method

Prestack reverse time migration （RTM） is an accurate imaging method ofsubsurface media. The viscoacoustic prestack RTM is of practical significance because itconsiders the viscosity of the subsurface media. One of the steps of RTM is solving thewave equation and extrapolating the wave field forward and backward; therefore, solvingaccurately and efficiently the wave equation affects the imaging results and the efficiencyof RTM. In this study, we use the optimal time-space domain dispersion high-order finite-difference （FD） method to solve the viscoacoustic wave equation. Dispersion analysis andnumerical simulations show that the optimal time-space domain FD method is more accurateand suppresses the numerical dispersion. We use hybrid absorbing boundary conditions tohandle the boundary reflection. We also use source-normalized cross-correlation imagingconditions for migration and apply Laplace filtering to remove the low-frequency noise.Numerical modeling suggests that the viscoacoustic wave equation RTM has higher imagingresolution than the acoustic wave equation RTM when the viscosity of the subsurface isconsidered. In addition, for the wave field extrapolation, we use the adaptive variable-lengthFD operator to calculate the spatial derivatives and improve the computational efficiencywithout compromising the accuracy of the numerical solution.

Least squares reverse-time migration in the pseudodepth domain and reservoir exploration

Least squares reverse-time migration （LSRTM） is an inversion method that removes artificial images and preserves the amplitude of reflectivity sections. LSRTM has been used in reservoir exploration and processing of 4D seismic data. LSRTM is, however, a computationally costly and memory-intensive method. In this study, LSRTM in the pseudodepth domain was combined with the conjugate gradient method to reduce the computational cost while maintaining precision. The velocity field in the depth domain was transformed to the velocity field in the pseudodepth domain; thus, the total number of vertical sampling points was reduced and oversampling was avoided. Synthetic and field data were used to validate the proposed method. LSRTM in the pseudodepth domain in conjunction with the conjugate gradient method shows potential in treating field data.

Elp3 modulates neural crest and colorectal cancer migration requiring functional integrity of HAT and SAM domains

Cell migration is a finely tuned biological process that often involves epithelial-mesenchymal transition(EMT).EMT is typically characterized by the upregulation of mesenchymal markers such as Snail1.This process has been shown to be of critical importance to normal developmental processes,including neural crest migration and invasion.Interestingly,similar mechanisms are utilized in disease processes,such as tumor metastasis and migration.Notably,EMT and EMT-like processes confer tumor cells with the ability to migrate,invade,and adopt stem cell-like properties that largely account for immunosuppression and tumor recurrence.Therefore,identifying sensitive EMT markers may contribute to cancer prognosis and diagnosis in many facets.Previously,we showed that Elp3 plays an essential role during neural crest migration by stabilizing Snail1.In the current study,we further elucidate the molecular mechanism underlying colorectal cancer migration.We found that mElp3 exerted an identical function to xElp3 in modulating neural crest migration,and both HAT and SAM domains are imperative during this migratory process.Interestingly,overexpression of mElp3 in SW480 cells promoted cell migration and invasion,and we further showed that Elp3 stabilized Snail1 requiring integrity of both SAM and HAT domains.Our findings warrant further exploration of the specific target of Elp3 in cancer cells.

Traveltime tomography and prestack depth migration for vertical seismic profiling of an angle-domain walkaway on a complex surface

Walkaway VSP cannot obtain accurate velocity field,as it asymmetrically reflects ray path and provides uneven coverage to underground target,thereby presenting issues related to imaging quality.In this study,we propose combining traveltime tomography and prestack depth migration for VSP of an angle-domain walkaway,in a bid to establish accurate two-dimensional and three-dimensional(3 D)velocity models.First,residual curvature was defined to update velocity,and an accurate velocity field was established.To establish a high-precision velocity model,we deduced the relationship between the residual depth and traveltime of common imaging gathers(CIGs)in walkaway VSP.Solving renewal velocity using the least squares method,a four-parameter tomographic inversion equation was derived comprising formation dip angle,incidence angle,residual depth,and sensitivity matrix.In the angle domain,the reflected wave was divided into up-and down-transmitted waves and their traveltimes were calculated.The systematic cumulative method was employed in prestack depth migration of a complex surface.Through prestack depth migration,the offset-domain CIGs were obtained,and dip angle was established by defining the stack section horizon.Runge–Kutta ray tracing was employed to calculate the ray path from the reflection point to the detection point,to determine the incident angle,and to subsequently calculate the ray path from the reflection point to the irregular surface.The offset-domain residual depths were mapped to the angle domain,and a new tomographic equation was established and solved.Application in the double complex area of the Tarim Basin showed the four-parameter tomographic inversion equation derived in this paper to be both correct and practical and that the migration algorithm was able to adapt to the complex surface.

High angle prestack depth migration with absorption compensation

The absorption effect of actual subsurface media can weaken wavefield energy, decrease the dominating frequency, and further lead to reduced resolution. In migration, some actions can be taken to compensate for the absorption effect and enhance the resolution. In this paper, we derive a one-way wave equation with an attenuation term based on the time- space domain high angle one-way wave equation. A complicated geological model is then designed and synthetic shot gathers are simulated with acoustic wave equations without and with an absorbing term. The derived one-way wave equation is applied to the migration of the synthetic gathers without and with attenuation compensation for the simulated shot gathers. Three migration profiles are obtained. The first and second profiles are from the shot gathers without and with attenuation using the migration method without compensation, the third one is from the shot gathers with attenuation using the migration method with compensation. The first and third profiles are almost the same, and the second profile is different from the others below the absorptive layers. The amplitudes of the interfaces below the absorptive layers are weak because of their absorption. This method is also applied to field data. It is concluded from the migration examples that the migration method discussed in this paper is feasible.

Plate tectonic control on the formation and tectonic migration of Cenozoic basins in northern margin of the South China Sea

The tectonic evolution history of the South China Sea(SCS) is important for understanding the interaction between the Pacific Tectonic Domain and the Tethyan Tectonic Domain,as well as the regional tectonics and geodynamics during the multi-plate convergence in the Cenozoic.Several Cenozoic basins formed in the northern margin of the SCS,which preserve the sedimentary tectonic records of the opening of the SCS.Due to the spatial non-uniformity among different basins,a systematic study on the various basins in the northern margin of the SCS constituting the Northern Cenozoic Basin Group(NCBG) is essential.Here we present results from a detailed evaluation of the spatial-temporal migration of the boundary faults and primary unconformities to unravel the mechanism of formation of the NCBG.The NCBG is composed of the Beibu Gulf Basin(BBGB),Qiongdongnan Basin(QDNB),Pearl River Mouth Basin(PRMB) and Taixinan Basin(TXNB).Based on seismic profiles and gravity-magnetic anomalies,we confirm that the NE-striking onshore boundary faults propagated into the northern margin of the SCS.Combining the fault slip rate,fault combination and a comparison of the unconformities in different basins,we identify NE-striking rift composed of two-stage rifting events in the NCBG:an early-stage rifting(from the Paleocene to the Early Oligocene) and a late-stage rifting(from the Late Eocene to the beginning of the Miocene).Spatially only the late-stage faults occurs in the western part of the NCBG(the BBGB,the QDNB and the western PRMB),but the early-stage rifting is distributed in the whole NCBG.Temporally,the early-stage rifting can be subdivided into three phases which show an eastward migration,resulting in the same trend of the primary unconformities and peak faulting within the NCBG.The late-stage rifting is subdivided into two phases,which took place simultaneously in different basins.The first and second phase of the early-stage rifting is related to back-arc extension of the Pacific subduction retreat system.The third phase of the earlystage rifting resulted from the joint effect of slab-pull force due to southward subduction of the proto-SCS and the back-arc extension of the Pacific subduction retreat system.In addition,the first phase of the late-stage faulting corresponds with the combined effect of the post-collision extension along the Red River Fault and slab-pull force of the proto-SCS subduction.The second phase of the late-stage faulting fits well with the sinistral faulting of the Red River Fault in response to the Indochina Block escape tectonics and the slab-pull force of the proto-SCS.

Structure and Migration Characteristic of Heterointerfaces During the Phase Transformation from L1_2 to DO_(22) Phase

Based on the microscopic phase-field model, the structure and migration characteristic of ordered domain interfaces formed between DO22 and L12 phase are investigated, and the atomistic mechanism of phase transformation from L12 （Ni3Al） to DO22 （Ni3V） in Ni75AlxV25-x alloys are explored, using the simulated microstructure evolution pictures and the occupation probability evolution of alloy elements at the interface. The results show that five kinds of heterointerfaces are formed between DO22 and L12 phase and four of them can migrate during the phase transformation from L12 to DO22 except the interface （002）D//（001）L. The structure of interface （100）D//（200）L and interface （100）D//（200）L·^1/2[001] remain the same before and after migration, while the interface （002）D//（002）L is formed after the migration of interface （002）D//（002）L·^1/2[100] and vice versa. These two kinds of interface appear alternatively. The jump and substitute of atoms selects the optimization way to induce the migration of interface during the phase transformation, and the number of atoms needing to jump during the migration is the least among all of the possible atom jump modes.

3D prestack reverse time migration of ground penetrating radar data based on the normalized correlation imaging condition

The reverse time migration(RTM)of ground penetrating radar(GPR)is usually implemented in its two-dimensional(2D)form,due to huge computational cost.However,2D RTM algorithm is difficult to focus the scattering signal and produce a high precision subsurface image when the object is buried in a complicated subsurface environment.To better handle the multi-off set GPR data,we propose a three-dimensional(3D)prestack RTM algorithm.The high-order fi nite diff erence time domian(FDTD)method,with the accuracy of eighth-order in space and second-order in time,is applied to simulate the forward and backward extrapolation electromagnetic fi elds.In addition,we use the normalized correlation imaging condition to obtain pre-stack RTM result and the Laplace fi lter to suppress the low frequency noise generated during the correlation process.The numerical test of 3D simulated GPR data demonstrated that 3D RTM image shows excellent coincidence with the true model.Compared with 2D RTM image,the 3D RTM image can more clearly and accurately refl ect the 3D spatial distribution of the target,and the resolution of the imaging results is far better.Furthermore,the application of observed GPR data further validates the eff ectiveness of the proposed 3D GPR RTM algorithm,and its fi nal image can more reliably guide the subsequent interpretation.

轴承变工况故障的域自适应迁移深度学习诊断

为了实现变设备、变工况条件下的轴承故障精确识别,提出了基于域自适应迁移深度卷积神经网络的诊断方法。对于具有不同分布特征(即不同域)的训练集和测试集,在深度卷积神经网络中构造了故障特征提取模块、域识别模块、标签分类模块,以特征提取模块与域识别模块对抗训练的方式实现域自适应迁移能力,使深度卷积神经网络能够有效提取不同域的共同特征参数。使用凯斯西储大学和智能维护系统中心数据设计了4组迁移实验,传统深度卷积神经网络的识别精度均值为64.5%,域自适应迁移卷积神经网络的识别精度均值为94.9%,充分说明了域自适应迁移深度卷积神经网络能够有效识别变设备、变工况条件下的轴承故障。

PI3K/Akt信号通路通过上调HKDC1促进人肝癌HepG2细胞糖酵解、增殖及迁移

目的探讨磷脂酰肌醇-3-激酶/蛋白激酶B(PI3K/Akt)通过调节含己糖激酶结构域的蛋白1(HKDC1)对人肝癌HepG2细胞糖酵解、增殖和迁移的影响及机制。方法将体外培养的对数期人肝癌HepG2细胞,分为对照组、LY294002组和MK-2206组,RT-qPCR法检测各组细胞HKDC1 mRNA的表达水平,western blotting法分析各组细胞HKDC1蛋白的表达水平。将细胞分为si-NC组(转染si-NC)、si-HKDC1组(转染si-HKDC1),western blotting法分析各组细胞HKDC1蛋白的表达水平,CCK-8、5-乙炔基-2′-脱氧尿苷(EdU)实验检测各组细胞增殖活力和划痕,Transwell实验检测各组细胞迁移率,细胞外酸化率(ECAR)实验检测分析各组细胞的糖酵解和糖酵解能力,葡萄糖及乳酸含量测定实验检测各组细胞内葡萄糖及乳酸含量。将细胞分为对照组、LY294002组、过表达HKDC1+LY294002组、MK-2206组、过表达HKDC1+MK-2206组,葡萄糖及乳酸含量测定实验检测各组细胞内葡萄糖及乳酸含量。结果与对照组比较,LY294002组细胞HKDC1 mRNA表达明显降低(P<0.001),HKDC1蛋白表达降低(P<0.01);MK-2206组细胞HKDC1 mRNA表达降低(P<0.01),HKDC1蛋白表达明显降低(P<0.001)。与si-NC组相比,si-HKDC1组细胞HKDC1蛋白表达降低(P<0.001);与si-NC组相比,si-HKDC1组细胞增殖活力降低(P<0.05),EdU阳性细胞数明显减少(P<0.01);与si-NC组相比,si-HKDC1组细胞划痕愈合率明显降低(P<0.001),迁移细胞数明显减少(P<0.001);与si-NC组相比,si-HKDC1组细胞糖酵解和糖酵解能力明显减弱(P<0.01);与si-NC组相比,si-HKDC1组细胞内葡萄糖和乳酸含量明显降低(P<0.05)。与LY294002组相比,过表达HKDC1+LY294002组细胞内葡萄糖和乳酸含量明显升高(P<0.01);与MK-2206组相比,过表达HKDC1+MK-2206组细胞内葡萄糖和乳酸含量明显升高(P<0.001,P<0.01)。结论PI3K/Akt信号通路通过HKDC1促进人肝癌HepG2细胞糖酵解、增殖和迁移。

准噶尔盆地复杂山地区分方位地震处理关键技术及应用

准噶尔盆地南缘山前冲断带是我国西部重要的油气勘探领域,构造复杂,逆冲断裂发育特征为油气勘探带来巨大挑战。随“两宽一高”资料的普及,全方位处理模式愈发难以满足深层精细勘探的需求。本文以安集海背斜为例,对下组合方位各向异性问题,提出一套完整的分方位处理流程,包括分方位速度分析、分方位全局寻优剩余静校正、OVT域叠前时间偏移及加权叠加技术。这些技术的应用有效地改善了该地区断点断裂不清晰和构造样式存在多解性的问题,具一定生产推广价值。

抑制lncRNA TUG1下调核苷酸结合寡聚结构域样受体蛋白1炎症小体在延缓阿尔茨海默病进展的作用

目的探讨敲低长链非编码RNA(lncRNA)牛磺酸上调基因1(TUG1)抑制核苷酸结合寡聚结构域样受体蛋白1(NLRP1)炎症小体在缓解阿尔茨海默病进展中的作用。方法选取9~10周龄遗传背景为C57/BL6的野生型小鼠(WT组,10只)或淀粉样前体蛋白(APP)/早老素1(PS1)转基因小鼠(30只)。APP/PS1转基因小鼠随机分为模型(model)组,模型+敲低lncRNA TUG1组[model+lncRNA TUG1短发夹RNA(shRNA)组]和model+shRNA非靶标(NT)组,每组10只。分别采集12周龄第1天(3月龄)和32周龄第1天(8月龄)小鼠外周血和脑皮质组织,并分离皮质中的原代小胶质细胞和原代星形胶质细胞,每个时间点每组5只小鼠。Real-time PCR分别测定3月龄和8月龄上述4个分组小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和巨噬细胞移动抑制因子(MIF)mRNA的水平,以及原代星形胶质细胞中补体蛋白C1r和C1s mRNA的水平。ELISA法测定其外周血浆中MIF含量。对3月龄和8月龄小鼠脑皮质原代小胶质细胞和原代星形胶质细胞共培养。CCK-8法测定上述2种细胞的增殖能力。Western blotting分别测定3月龄和8月龄上述4个分组小鼠脑皮质组织中MIF、白细胞介素1β前体(pro-IL-1β)、凋亡相关斑点样蛋白(ASC)、Caspase-1(p20)、Caspase-1(full)、NLRP1及NLRP3蛋白的表达水平。采用免疫荧光染色法测定8月龄各分组小鼠脑皮质组织中β淀粉样蛋白(Aβ)表达。结果3月龄和8月龄时,与WT组小鼠相比,model组小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和MIF相对表达水平显著上调,原代小胶质细胞和原代星形胶质细胞增殖能力增强(P<0.05)。与model组相比,model+lncRNA TUG1 shRNA组小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和MIF的相对表达水平显著降低,原代小胶质细胞和原代星形胶质细胞增殖能力降低(P<0.05)。与WT组相比,model组小鼠外周血浆中MIF含量显著升高;小鼠脑皮质组织中pro-IL-1β、ASC、Caspase-1(p20)、Caspase-1(full)、NLRP1以及NLRP3的蛋白表达水平显著升高;Aβ免疫荧光强度明显增强(P<0.05)。与model组相比,model+lncRNA TUG1 shRNA组小鼠外周血浆中MIF含量显著降低;小鼠脑皮质组织中pro-IL-1β、ASC、Caspase-1(p20)、Caspase-1(full)和NLRP1的蛋白表达水平显著降低,Aβ免疫荧光强度明显降低(P<0.05),而NLRP3蛋白质的表达水平无明显变化(P>0.05)。与model组相比,model+shRNA NT组小鼠上述所有检测指标差异均无显著性(P>0.05)。结论APP/PS1转基因小鼠脑皮质组织和原代小胶质细胞中lncRNA TUG1和MIF因子表达上调与脑皮质内NLRP1炎症小体激活成正相关,敲低lncRNA TUG1可缓解阿尔茨海默病的进展。

己糖激酶结构域成分1基因敲除对人结直肠癌细胞的增殖、迁移及侵袭能力的影响

目的 探讨己糖激酶结构域成分1(HKDC1)对人结直肠癌细胞增殖、迁移、侵袭能力的影响。方法 HT-29、SW480细胞进行瞬时转染,设置HKDC1-si RNA组、阴性对照组及空白组。同时收集2020年3月至2022年5月河北北方学院附属第一医院接受手术的50例患者的结直肠癌组织和癌旁正常组织。RT-q PCR实验检测HKDC1 m RNA表达;Western blot实验检测HKDC1蛋白表达;CCK-8实验、划痕实验和Transwell实验检测细胞增殖、迁移和侵袭能力。结果 HT-29细胞HKDC1 m RNA的表达量高于SW480细胞(P<0.05),故选取HT-29细胞株用于后续实验。结直肠癌组织中HKDC1 m RNA、光密度值高于癌旁正常组织(P<0.05)。空白组与阴性对照组HKDC1 m RNA、蛋白表达水平比较,差异无统计学意义(P>0.05);HKDC1-si RNA组HKDC1 m RNA、蛋白表达水平低于阴性对照组(P<0.05)。空白组与阴性对照组光密度值比较,差异无统计学意义(P>0.05);HKDC1-si RNA组光密度值低于阴性对照组(P<0.05)。空白组与阴性对照组细胞迁移率比较,差异无统计学意义(P>0.05);HKDC1-si RNA组细胞迁移率低于阴性对照组(P<0.05)。空白组与阴性对照组细胞迁移数目比较,差异无统计学意义(P>0.05);HKDC1-si RNA组细胞迁移数目低于阴性对照组(P<0.05)。结论 HKDC1在结直肠癌组织及细胞中高表达,可促进结直肠癌细胞的增殖、迁移及侵袭能力,有望成为结直肠癌基因治疗的新靶点。

曲面构件阵列超声频域逆时偏移成像方法研究

曲面构件因其独特的结构和力学特性,广泛应用于航空航天领域。然而,未知的曲面形状导致阵列超声检测时,声传播延时计算不准确,影响缺陷检测的精度。为解决这一问题,提出了一种不依赖声传播延时的适用于曲面构件的阵列超声频域逆时偏移成像方法。首先,利用阵列超声全聚焦方法对曲面构件表面进行成像;然后,对成像结果进行阈值分割和曲线拟合,重构构件表面形状并建立二维声学特性分布模型;最后,通过频域逆时偏移将来自超声波源的正向传播波场与缺陷反射体的反向传播波场进行互相关成像。实验结果表明,所提出的方法可以有效实现曲面构件内部缺陷成像,与传统的阵列超声全聚焦方法相比,缺陷的成像质量提升66%以上,缺陷定量平均误差降低37.04%以上。

基于弹性反射波正演表达的转换波逆时偏移与反偏移

针对线性化弹性反射波方程无法直接用于弹性转换波反偏移模拟的问题,本文提出基于高频近似的一次反射波模拟新方法.该方法基于地震波传播的散射理论,先对地下速度扰动的空间变化进行高频近似,再基于散射波传播方程推导得到线性化一次反射波传播方程.基于弹性反射地震数据表达,本文采用线性算子的伴随估计反射系数,实现反射波逆时偏移.根据该线性表达,联合背景速度和成像值来模拟一次反射横波传播,实现了弹性波角度域反偏移,并进一步导出成像值关于波速的梯度.数值实验表明,基于弹性反射地震数据表达的偏移成像方法,既克服了极性反转效应,又使成像结果包含了更为丰富的反射角信息;一次反射波模拟方法获得的弹性地震数据具有较高的精度和稳定性,得到的弹性波场的振幅和相位信息与理论解析解吻合较好,有效保证了成像域层析速度反演梯度的稳定求解.

TMEFF1对神经母细胞瘤细胞系增殖的调控

目的探究具有表皮生长因子结构域和两个卵泡抑素样结构域的跨膜蛋白1(TMEFF1/tomoregulin1)对神经母细胞瘤(NB)细胞系SN-K-BE(2)增殖和迁移的调控效应。方法RT-qPCR检测神经母细胞瘤细胞系SN-K-BE(2)、IMR32、SK-N-SH、SK-N-AS和正常细胞系MCF 10A、hTERT RPE-1中TMEFF1 mRNA表达量。利用小分子干扰RNA(siRNA)瞬时敲低MCF 10A、hTERT RPE-1细胞和SN-K-BE(2)NB细胞中TMEFF1表达,RT-qPCR检测TMEFF1 mRNA瞬时敲低效果后,结晶紫染色、实时无标记细胞分析(RTCA)检测细胞增殖;CellTiter-Glo(CTG)检测细胞活性。利用短发夹RNA(shRNA)稳定敲低正常细胞系和NB细胞系中TMEFF1表达,进一步通过集落形成实验、RTCA、CTG检测细胞增殖和活性,此外,通过免疫荧光检测Ki-67细胞阳性率,细胞划痕实验检测细胞迁移率。结果与正常细胞系相比,NB细胞系中TMEFF1 mRNA表达量显著较高(P<0.001)。敲低TMEFF1对正常细胞系增殖影响无统计学意义,但在SN-K-BE(2)细胞中敲低TMEFF1,RTCA和集落形成实验结果显示细胞增殖能力减弱(P<0.05),免疫荧光结果显示Ki-67阳性细胞率减少(P<0.001),CTG结果显示细胞活性降低(P<0.01),细胞划痕实验结果显示敲低组细胞迁移率显著低于对照组(P<0.01)。结论TMEFF1是一种特异在NB细胞中高表达的膜蛋白,TMEFF1敲低后不影响正常细胞系的增殖,但显著抑制NB细胞系的增殖、迁移,提示TMEFF1可能在NB发生发展中发挥重要作用,可能成为NB靶向治疗的潜在新靶点。

EnGAN:医学图像分割中的增强生成对抗网络

原始采集的医学图像普遍存在对比度不足、细节模糊以及噪声干扰等质量问题,使得现有医学图像分割技术的精度很难达到新的突破。针对医学图像数据增强技术进行研究,在不明显改变图像外观的前提下,通过添加特定的像素补偿和进行细微的图像调整来改善原始图像质量问题,从而提高图像分割准确率。首先,设计引入了一个新的优化器模块,以产生一个连续分布的空间作为迁移的目标域,该优化器模块接受数据集的标签作为输入,并将离散的标签数据映射到连续分布的医学图像中;其次,提出了一个基于对抗生成网络的EnGAN模型,并将优化器模块产生的迁移目标域用来指导对抗网络的目标生成,从而将改善的医学图像质量知识植入模型中实现图像增强。基于COVID-19数据集,实验中使用U-Net、U-Net+ResNet34、U-Net+Attn Res U-Net等卷积神经网络作为骨干网络,Dice系数和交并比分别达到了73.5%和69.3%、75.1%和70.5%,以及75.2%和70.3%。实验的结果表明,提出的医学图像质量增强技术在最大限度保留原始特征的条件下,有效地提高了分割的准确率,为后续的医学图像处理研究提供了一个更为稳健和高效的解决方案。

脂代谢相关基因ABHD5抑制肾癌细胞体外迁移及侵袭

目的:探讨透明细胞肾细胞癌(clear cell renal cell cancinoma,ccRcc)细胞体外迁移及侵袭过程中与α/β自水解酶结构域5(α/β-hydrolase domain-containing 5,ABHD5)的关系。方法:采用TCGA数据库分析人ccRcc组织及正常肾组织中ABHD5的表达情况。采用ABHD5过表达慢病毒转染人肾透明细胞癌细胞株786-O及Caki-1后,运用real-time PCR及Western blot技术检测ABHD5表达改变情况。采用Transwell实验、划痕实验检测此基因对细胞体外迁移及侵袭能力的影响。结果:TCGA数据库显示ccRcc组织中ABHD5表达较正常肾脏组织显著下降(P=0.000),且其下降程度在复发转移肿瘤中进一步增加(P=0.007),与患者生存呈显著负相关(P<0.001)。Transwell实验、划痕实验显示过表达ABHD5显著抑制肾癌细胞体外迁移及侵袭能力(P<0.05)。过表达ABHD5通过影响Sting信号进而影响肾癌细胞体外迁移及侵袭。结论:脂代谢相关基因ABHD5抑制ccRcc癌细胞体外迁移及侵袭能力。