Objective To investigate the association between v-Ki-ras2 Kirsten rat sarcoma viral oncogene homologue (KRAS) gene mutations and levels of human leucocyte antigen (HLA) class I antigen in primary lung tumours and metastatic lymph nodes of patients with non-small cell lung cancer (NSCLC). Methods Patients with NSCLC undergoing tumour resection were enrolled. KRAS codon 12 mutations were analysed in normal lung and lymph node tissue, primary lung tumours and metastatic lymph nodes using polymerase chain reaction-restriction fragment length polymorphism analysis. HLA class I antigen immunostaining was examined using flow cytometry. Results A total of 65 patients participated in the study. All normal lung tissues had positive HLA class I antigen immunostaining. The majority of primary lung tumours (56/65) and all of the metastatic lymph nodes (31/31) had downregulated HLA class I antigen immunostaining. There was a positive correlation between downregulated HLA class I antigen in primary tumours and metastatic lymph nodes. There was a negative correlation between KRAS codon 12 mutations and the level of HLA class I antigen in primary and metastatic tumours. Conclusions KRAS codon 12 mutations appear to be important in the downregulation of HLA class I antigen in NSCLC. Abnormal activation of the oncogenic KRAS pathway might provide a new treatment target for NSCLC.

https://imr.sagepub.com/content/41/5/1473.full.pdf

The relationship between KRAS gene mutations and HLA class I antigen downregulation in the metastasis of non-small cell lung cancer

Cellular membranes are heterogeneous planar lipid bilayers displaying lateral phase separation with the nanometer-scale liquid-ordered phase (also known as “lipid rafts”) surrounded by the liquid-disordered phase. Many membrane-associated proteins were found to permanently integrate into the lipid rafts, which is critical for their biological function. Isoforms H and N of Ras GTPase possess a unique ability to switch their lipid domain preference depending on the type of bound guanine nucleotide (GDP or GTP). This behavior, however, has never been demonstrated in vitro in model bilayers with recombinant proteins and therefore has been attributed to the action of binding of Ras to other proteins at the membrane surface. In this paper, we report the observation of the nucleotide-dependent switch of lipid domain preferences of the semisynthetic lipidated N-Ras in lipid raft vesicles in the absence of additional proteins. To detect segregation of Ras molecules in raft and disordered lipid domains, we measured...

/pdf/study-of-forster-resonance-energy-transfer-to-lipid-domain-1yypxb9piz.pdf

Study of Förster Resonance Energy Transfer to Lipid Domain Markers Ascertains Partitioning of Semisynthetic Lipidated N-Ras in Lipid Raft Nanodomains.

Abstract We present an experimental investigation of the flow structure in the near wake of a NACA0012 airfoil plunging sinusoidally at a chord Reynolds number of Re = 20 000 and for a wide range of reduced frequency k and Strouhal number based on peak-to-peak amplitude St. Estimated mean thrust coefficients using the mean and fluctuating velocity fields confirm the St2 dependence as well as a significant effect of the reduced frequency for k ≤ 1. Generally, time-averaged flow quantities are better correlated with St than k in the range tested (k ≤ 3.14 and St ≤ 0.24). Analysis of the streamwise flow and cross-flow in the near wake using two-point cross-correlations and proper orthogonal decomposition reveals that the unsteady characteristics are even better correlated with St than the mean flow quantities. The percentage energy of the fundamental wake modes of the streamwise flow and the flapping mode of the cross-flow increases with increasing St, but at different rates in the drag-producing and thrust-producing wakes. There are similarities to the wake synchronisation behind oscillating bodies. The spanwise-averaged cross-correlation coefficient in the measurement domain grows linearly for small St (in drag-producing wakes), and is nearly constant at a high value for larger St (in thrust-producing wakes). Results show that the Strouhal number is the most important parameter that determines the degree of two-dimensionality of the wake, and suggest that spanwise vortices are quasi-two-dimensional for St ≥ 0.05 and x/c ≤ 4. The implications for experimental gust generators using oscillating airfoils are discussed.

/pdf/coherence-of-unsteady-wake-of-periodically-plunging-airfoil-3eypgjy5.pdf

Coherence of unsteady wake of periodically plunging airfoil

Conditional image-to-video (cI2V) generation aims to synthesize a new plausible video starting from an image (e.g., a person's face) and a condition (e.g., an action class label like smile). The key challenge of the cI2V task lies in the simultaneous generation of realistic spatial appearance and temporal dynamics corresponding to the given image and condition. In this paper, we propose an approach for cI2V using novel latent flow diffusion models (LFDM) that synthesize an optical flow sequence in the latent space based on the given condition to warp the given image. Compared to previous direct-synthesis-based works, our proposed LFDM can better synthesize spatial details and temporal motion by fully utilizing the spatial content of the given image and warping it in the latent space according to the generated temporally-coherent flow. The training of LFDM consists of two separate stages: (1) an unsupervised learning stage to train a latent flow auto-encoder for spatial content generation, including a flow predictor to estimate latent flow between pairs of video frames, and (2) a conditional learning stage to train a 3D-UNet-based diffusion model (DM) for temporal latent flow generation. Unlike previous DMs operating in pixel space or latent feature space that couples spatial and temporal information, the DM in our LFDM only needs to learn a low-dimensional latent flow space for motion generation, thus being more computationally efficient. We conduct comprehensive experiments on multiple datasets, where LFDM consistently outperforms prior arts. Furthermore, we show that LFDM can be easily adapted to new domains by simply finetuning the image decoder. Our code is available at https://github.com/nihaomiao/CVPR23_LFDM.

Conditional Image-to-Video Generation with Latent Flow Diffusion Models

We analyze the incompressible flow past a square cylinder immersed in the wake of an upstream splitter plate, which separates two streams of different velocities, U T (top) and U B (bottom). The Reynolds number associated with the flow below the plate is kept constant at [Formula: see text], based on the square cylinder side D as characteristic length. The top-to-bottom flow dissymmetry is measured by the ratio [Formula: see text] between the Reynolds numbers above and below the plate. The equivalent bulk Reynolds taken as the mean between top and bottom changes with R in the range [Formula: see text]. A Hopf bifurcation occurs at [Formula: see text] ([Formula: see text]), which results in an asymmetric Kármán vortex street with vortices only showing on the high-velocity side of the wake. A spanwise modulational instability is responsible for the three-dimensionalization of the flow at [Formula: see text] ([Formula: see text]) with the associated wavelength of [Formula: see text]. For velocity ratios [Formula: see text], the flow becomes spatiotemporally chaotic. The migration of the mean stagnation and base pressure points on the front and rear surfaces of the cylinder as R is increased determine the boundary layer properties on the top and bottom surfaces and, with them, the shear layers that roll up into the formation of Kármán vortices, which in turn help to clarify the evolution of the lift and drag coefficients. The symmetries of the different solutions across the flow transition regime are imprinted on the top and bottom boundary layers and can, therefore, be analyzed from the time evolution and spanwise distribution of trailing edge boundary layer displacement thickness at the top and bottom rear corners. 

/pdf/aerodynamic-performances-and-wake-topology-past-a-square-209dc87c.pdf

Aerodynamic performances and wake topology past a square cylinder in the interface of two different-velocity streams

Abstract The aerodynamics of a stationary wing in a turbulent wake are investigated. Force and velocity measurements are used to describe the unsteady flow. Various wakes are studied with different dominant frequencies and length scales. In contrast to the pre-stall angles of attack, the time-averaged lift increases substantially at post-stall angles of attack as the wing interacts with the von Kármán vortex street and experiences temporal variations of the effective angle of attack. At an optimal offset distance from the wake centreline, the time-averaged lift becomes maximum despite of small amplitude oscillations in the effective angle of attack. The stall angle of attack can reach 20° and the maximum lift coefficient can reach 64 % higher than that in the freestream. Whereas large velocity fluctuations at the wake centreline cause excursions into the fully attached and separated flows during the cycle, small-amplitude oscillations at the optimal location result in periodic shedding of leading edge vortices. These vortices may produce large separation bubbles with reattachment near the trailing-edge. Vorticity roll-up, strength and size of the vortices increase with increasing wavelength and period of the von Kármán vortex street, which also coincides with an increase in the spanwise length scale of the incident wake, and all contribute to the remarkable increase in lift.

/pdf/aerodynamics-of-a-wing-in-turbulent-bluff-body-wakes-3hp9lrul.pdf

Aerodynamics of a wing in turbulent bluff body wakes

Input: Pre-trained transformer-based backbone f , final classification layer f , number of tasks T , training set {(xi,t, yi,t)}t i=1} T t=1, G-Prompt g, E-Prompt E = {et}t=1, task keys K = {kt}t=1, startg, endg, starte, ende, prompting function fprompt, number of training epochs of the t-th task Mt Initialize: , g, E, K for t = 1, · · · , T do Select the task-specific E-Prompt et and corresponding task key kt Generate the prompted architecture fg,et : attach g and et to startg-th to endg-th and starte-th to ende-th MSA layers respectively, with fprompt. for e = 1, · · · ,Mt do Draw a mini-batch B = {(xi,t, yi,t)}i=1 for (x, y) in B do Calculate the prompted feature by fg,et(x) Calculate the per sample loss Lx via equation 6 end Update , g, E, K by backpropagation end end

Complementary Prompting for Rehearsal-free Continual Learning 19 Algorithm 1: DualPrompt at training time

The ras gene family provides a global effect on gene expression by encoding small GTP-binding proteins which act as molecular switches connecting extracellular signals with nuclear transcription factors. Mutations on the K-ras gene have been found in 20-30% of non-small-cell lung cancers are believed to play a key role in this malignancy. The ras-signaling pathway has attracted considerable attention as a target for anticancer therapy because of its important role in carcinogenesis. This review summarizes the structure and function of K-ras, with attention to the facets of K-ras biology that relate to tumorigenesis and focuses on those that have been targeted for lung cancer therapy.

Z Zhang

Papers

Aerodynamics of a wing in turbulent bluff body wakes

Complementary Prompting for Rehearsal-free Continual Learning 19 Algorithm 1: DualPrompt at training time

K-ras role in lung cancer therapy.

Impact of pre-existing crystal lattice defects on the accumulation of irradiation-induced damage in a C/C composite

OC-0458 Combined radiomics and dosiomics predicts radiation pneumonitis : a model with external validation