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Carotid artery plaques pose a significant threat to human life and health, with the hemodynamics playing a crucial role in their formation and progression. In this study, we reconstructed geometric models of pre-pathological carotid arteries from the computed tomography angiography images. Using computational methods of fluid–structure interaction, key hemodynamic parameters that influence the plaques formation are investigated in the carotid arteries, such as time-averaged wall shear stress and oscillatory shear index (OSI). Additionally, a correlation between the shape index of endothelial cells and the hemodynamic parameters is established. Then, combining the pathology of atherosclerosis, a set of mathematical models is constructed to describe the transendothelial transport and evolution of key substances involved in plaque formation within the carotid arterial wall, thereby predicting high-risk areas for plaque formation. The results indicate a higher risk area around the carotid bifurcation, consistent with recirculation zones of blood flow and characterized by low WSS and high OSI. The risk areas predicted by our mathematical models are well validated by clinical images, suggesting the accuracy of models established in the study. This method predicts high-risk areas of plaque formation and provides valuable guidance for the clinical diagnosis and treatment. [ABSTRACT FROM AUTHOR]

In this study, the growth and rupture of plaque were investigated to predict the development of carotid atherosclerosis and plaque. Realistic 3D models of multi-component plaque and carotid artery were established in healthy, mild, moderate, and severe stenosis. Fluid–structure interaction (FSI) simulations were performed on these models, and the wall shear stress (WSS), time-averaged wall shear stress (TAWSS), oscillatory shear index (OSI), relative residence time (RRT), and wall tensile stress (WTS) in a natural cardiac cycle were analyzed to assess the epidermal rupture, growth tendency, and internal rupture of plaques in a natural state. Results show that in severe stenosis, the WSS at the stenosis sites exceeds the threshold of rupture during almost the entire cardiac cycle, thus causing an epidermal injury, bringing about plaque detachment and thrombosis. TAWSS decreased and OSI and RRT increased in the bifurcation region and the downstream region of the plaque. The deposition is more likely to occur in these regions. A higher degree of stenosis will increase the OSI and RRT in the downstream region of the plaque, leading to continuous deterioration of the plaque, while the degree of stenosis has little effect on the upstream region of the plaque. The fibrous cap is the starting point for rupture within the plaque, and calcification increases the stress on the fibrous cap, thereby increasing the risk of rupture. [ABSTRACT FROM AUTHOR]

Summary: In maize (Zea mays L.), lateral roots are formed in the differentiation zone of all root types in a multi‐step process. The maize mutant lateral rootless 1 (lrt1) is defective in lateral root formation in primary and seminal roots but not in shoot‐borne roots.We cloned the lrt1 gene by mapping in combination with BSA‐seq and subsequent validation via CRISPR/Cas9.The lrt1 gene encodes a 209 kDa homolog of the DDB1‐CUL4‐ASSOCIATED FACTOR (DCAF) subunit of the CUL4‐based E3 ubiquitin ligase (CRL4) complex localized in the nucleus. DDB1‐CUL4‐ASSOCIATED FACTOR proteins are encoded by an evolutionary old gene family already present in nonseed plants. They are adaptors that bind substrate proteins and promote their ubiquitylation, thus typically marking them for subsequent degradation in the 26S proteasome. Gene expression studies demonstrated that lrt1 transcripts are expressed preferentially in the meristematic zone of all root types of maize. Downregulation of the rum1 gene in lrt1 mutants suggests that lrt1 acts upstream of the lateral root regulator rum1.Our results demonstrate that DCAF proteins play a key role in root‐type‐specific lateral root formation in maize. Together with its role in nitrogen acquisition in nitrogen‐poor soil, lrt1 could be a promising target for maize improvement. [ABSTRACT FROM AUTHOR]

Nanowrinkles (i.e. the buckled nanoribbons) are widely observed in nano-devices assembled by two-dimensional (2D) materials. The existence of nanowrinkles significantly affects the physical (such as mechanical, electrical and thermal) properties of 2D materials, and thus further, impedes the applications of those devices. In this paper, we take the nanowrinkle formed in a monolayer graphene as a model system to study its deformation behaviours, especially the configuration evolution and the snap-through buckling instabilities, when subjected to the out-of-plane compression. By performing molecular dynamics simulation, the graphene nanowrinkles with or without self-adhesion (which are notated as ‘clipped’ state or ‘bump’ state, respectively) are obtained depending on the geometric size and the applied axial compressive pre-strain. The elastica theory is employed to quantify the shape of ‘bump’ nanowrinkles, as well as the critical condition of the transition between ‘clipped’ and ‘bump’ states. By applying out-of-plane compression to the generated graphene nanowrinkle, it flips to an opposite configuration via snap-through buckling. We identify four different buckling modes according to the configuration evolution. An unified phase diagram is constructed to describe those buckling modes. For the cases with negligible van der Waals interaction getting involved in the snap-buckling process, i.e. without self-adhesion, the forceâ€"displacement curves for nanowrinkles with same axial pre-strain but different sizes can be scaled to collapse. Moreover, the critical buckling loads can also be scaled and predicted by the extended elastica theory. Otherwise, for the cases with self-adhesion, which corresponds to the greater axial pre-strain, the van der Waals interaction makes the scaling collapse break down. It is expected that the analysis about the snap-through buckling of graphene nanowrinkles reported in this work will advance the understanding of the mechanical behaviours of wrinkled 2D materials and promote the design of functional nanodevices, such as nanomechanical resonators and capacitors. [ABSTRACT FROM AUTHOR]

The biosynthesis of the light-harvesting complex (LHC) polypeptides of the green flagellate Mantoniella squamata (Manton et Parke) Desikachary (Micromonadophyceae, Chlorophyta) was examined by in vivo polypoptide labeling and immunoprecipitation of in vitro translation products. Using protein synthesis inhibitors, the LHC polypeptides were shown to be synthesized on 80S cytoplasmic ribosomes and not in the chloroplasts of cells. Poly (A)+RNA was isolated and proteins were synthesized by a rabbit reticulocyte lysate system, with antisera raised against M. squamata LHC used for immunoprecipitation from the translation products. One polypeptide 3-5 kDa larger than mature LHC polypeptides was immunoprecipitated. These studies indicate that although the LHC of M. squamata is quite different from the LHC of most green plants, the LHC polypeptides are synthesized as precursors in the cytoplasm of the cell and suggest that the genes encoding these polypeptides are located in the nucleus. [ABSTRACT FROM AUTHOR]

Insulators are cis -regulatory elements that separate transcriptional units, whereas silencers are elements that repress transcription regardless of their position. In plants, these elements remain largely uncharacterized. Here, we use the massively parallel reporter assay Plant STARR-seq with short fragments of eight large insulators to identify more than 100 fragments that block enhancer activity. The short fragments can be combined to generate more powerful insulators that abolish the capacity of the strong viral 35S enhancer to activate the 35S minimal promoter. Unexpectedly, when tested upstream of weak enhancers, these fragments act as silencers and repress transcription. Thus, these elements are capable of both insulating or repressing transcription dependent upon regulatory context. We validate our findings in stable transgenic Arabidopsis , maize, and rice plants. The short elements identified here should be useful building blocks for plant biotechnology efforts., Competing Interests: Competing interests T.J., J.T.C., and C.Q. have filed a patent application related to this work through the University of Washington. The remaining authors declare no competing interests.