Dietary microRNAs have been shown to be absorbed by mammals and regulate host gene expression, but the absorption mechanism remains unknown. Here, we show that SIDT1 expressed on gastric pit cells in ...the stomach is required for the absorption of dietary microRNAs. SIDT1-deficient mice show reduced basal levels and impaired dynamic absorption of dietary microRNAs. Notably, we identified the stomach as the primary site for dietary microRNA absorption, which is dramatically attenuated in the stomachs of SIDT1-deficient mice. Mechanistic analyses revealed that the uptake of exogenous microRNAs by gastric pit cells is SIDT1 and low-pH dependent. Furthermore, oral administration of plant-derived miR2911 retards liver fibrosis, and this protective effect was abolished in SIDT1-deficient mice. Our findings reveal a major mechanism underlying the absorption of dietary microRNAs, uncover an unexpected role of the stomach and shed light on developing small RNA therapeutics by oral delivery.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This paper presents a two‐dimensional corotational curved beam element for the dynamic analysis of curved viscoelastic beams with large deformations and rotations. In contrast with traditional ...straight beam elements, the novelty of the presented formulation lies in introducing a curved reference configuration, which follows the rotation and translation of a corotational frame, to measure the pure elastic deformation of the beam and describe the spatial position of an arbitrary material point. A curvilinear coordinate system is fixed on this reference configuration to measure the local deformation of the element. Based on Hamilton's principle, the global elastic force vector, the global internal damping force vector, the global inertia force vector, and the global external damping force vector are derived using the same shape functions to ensure the consistency and independence of the element. An accurate two‐node curved element and the Kelvin–Voigt model are introduced to consider the axial deformation, bending deformation, shear deformation, rotary inertia, and viscoelasticity of the beam. Three examples are given to verify the validity, computational accuracy, and computational efficiency of the presented formulation. Moreover, the effects of the internal damping and external damping on the dynamic response of a rotating curved beam are investigated.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Integrated optics has distinct advantages for applications in space because it integrates many elements onto a monolithic, robust chip. As the development of different building blocks for integrated ...optics advances, it is of interest to answer the important question of their resistance with respect to ionizing radiation. Here we investigate effects of proton radiation on high-Q (θ(10⁶)) silicon nitride microresonators formed by a waveguide ring. We show that the irradiation with high-energy protons has no lasting effect on the linear optical losses of the microresonators.
SUMMARY
Pollen formation and pollen tube growth are essential for the delivery of male gametes into the female embryo sac for double fertilization. Little is known about the mechanisms that regulate ...the late developmental process of pollen formation and pollen germination. In this study, we characterized a group of Arabidopsis AGC kinase proteins, NDR2/4/5, involved in pollen development and pollen germination. The NDR2/4/5 genes are mainly expressed in pollen grains at the late developmental stages and in pollen tubes. They function redundantly in pollen formation and pollen germination. At the tricellular stages, the ndr2 ndr4 ndr5 mutant pollen grains exhibit an abnormal accumulation of callose, precocious germination and burst in anthers, leading to a drastic reduction in fertilization and a reduced seed set. NDR2/4/5 proteins can interact with another group of proteins (MOB1A/1B) homologous to the MOB proteins from the Hippo signaling pathway in yeast and animals. The Arabidopsis mob1a mob1b mutant pollen grains also have a phenotype similar to that of ndr2 ndr4 ndr5 pollen grains. These results provide new evidence demonstrating that the Hippo signaling components are conserved in plants and play important roles in sexual plant reproduction.
Significance Statement
The AGC protein kinases NDR2/4/5 play important roles in the late development of pollen grains and the control of pollen germination through interaction with the MOB1A/1B proteins in Arabidopsis. This study suggests that the core components in the Hippo pathway, NDRs and MOBs, are also functionally conserved in plants.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In the year 2020, the Coronavirus (COVID-19) broke out in many countries of the world. In China, the Chinese government and people have adopted strong measures. After more than a month of fighting ...against the epidemic, the epidemic has been basically under control in China. However, in other countries of the world, such as South Korea, Japan, Iran, many countries in Europe, and the Americas, the epidemic is still developing rapidly and the situation is not optimistic. This paper summarizes the transport-related experience of China in the fight against the epidemic and hopes that it will be helpful to other countries in the fight against the epidemic.
•The article summarizes transport-related efforts to control Coronavirus spread in China.•The article analyzes the mechanisms for restricting flow of people to control the epidemic.•Transportation guarantee for key personnel and material distribution, a key strategy, is summarized.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Introduction Conducting Visual Display Terminal (VDT) visual search tasks under time constraint has broad applications in fields such as security checks, medical diagnostics, and rescue operations. ...While excessive time pressure can impair performance, moderate time pressure can motivate individuals to complete tasks and increase productivity. Investigating the positive impact of time pressure on visual search tasks has become a crucial area of study. Clock timing plays a vital role in the visual interface, influencing the perception of time pressure and impacting visual search performance. However, existing research has paid little attention to the induction of time pressure and the impact of clock timing in VDT visual interfaces on visual search performance. Hence, the objective of this study is to investigate the impact of clock timing on VDT visual search performance under time constraint. Methods The content of the experimental tasks was determined through a pilot experiment. The formal experiment was conducted in two phases over six sessions. Participants were tasked with locating the letter “E” embedded within the distractor letter “F,” displayed with a clock area above the interface. The first phase of experiments included conditions of no clock, 4-min clock timing, and 4-min countdown clock timing. In the second phase of the experiment, the clock display method was a countdown clock, with three experiments conducted featuring long time, medium time, and short time. Search speed and accuracy were used as primary performance evaluation metrics to examine the impact of clock timing methods and duration on visual search performance. Twenty-one undergraduate students participated in the formal experiment. Results In the first phase of experiments, participants demonstrated significantly faster reaction times (RTs) in tasks where a clock display was present compared to tasks without (ANOVA, F(2, 60) = 4.588, P = 0.014). However, there were no significant differences in accuracy rates across different timing conditions (ANOVA, F(2, 60) = 0.146, P = 0.865), and no significant correlation between RTs and accuracy was found (Kendall’s R = 0.11, P = 0.914). During the second phase, RTs decreased significantly as time constraints became more stringent (ANOVA, F(2, 60) = 7.564, P < 0.05). Conversely, accuracy rates decreased significantly under shorter time constraints (ANOVA, F(2, 60) = 4.315, P < 0.05), with a negative correlation observed between RTs and accuracy (Kendall’s R = 0.220, P < 0.01). Discussion Compared to conditions without clock displays, having clock displays significantly improved the speed of the visual search task, although the difference in accuracy was not statistically significant. In the context of shorter clock countdown limits, Shorter timing constraints resulted in faster search speeds but also led to reduced accuracy and increased fatigue. Overall, a correlation exists between search speed and accuracy in visual tasks, where higher speed often correlates with lower accuracy. These findings provide valuable insights into clock timing design for visual search interfaces under time pressure.
Background/Aims: Cardiac fibrosis after myocardial infarction (MI) has been identified as an important factor in the deterioration of heart function. Previous studies have demonstrated that miR-21 ...plays an important role in various pathophysiological processes in the heart. However, the role of miR-21 in fibrosis regulation after MI remains unclear. Methods: To induce cardiac infarction, the left anterior descending coronary artery was permanently ligated of mice. First, we explored the expression of miR-21 in the infarcted zone in mice model of MI via RT-qPCR. Next, we examined the effects of TGF-β1 on miR-21 expression in cardiac fibroblasts (CFs). Then, CFs were infected with miR-21 mimics or miR-21 inhibitors to investigate the effects of miR-21 on the process of CFs activation in vitro. Further, bioinformatics analysis and luciferase reporter assay were performed to identify and validate the target gene of miR-21. At last, in-vivo study was done to confirm MiR-21 regulated myocardial fibrosis after MI in mice. Results: MiR-21 was up-regulated in the infarcted zone after MI in vivo. TGF-β1 treatment increased miR-21 expression in CFs. Overexpression of miR-21 promoted the effects of TGF-β1-induced activation of CFs, evidenced by increased expression of Col-1, α-SMA and F-actin, whereas inhibition of miR-21 attenuated the process of fibrosis. Bioinformatics, Western blot analysis and luciferase reporter assay demonstrated that Smad7 is a direct target of miR-21. In addition, in-vivo study revealed that MiR-21 regulated myocardial fibrosis after MI in mice. Conclusion: These findings suggested that miR-21 has a critical role in CF activation and cardiac fibrosis after MI through via TGF-β/Smad7 signaling pathway. Thus, miR-21 promises to be a potential therapy in treatment of cardiac fibrosis after MI.
This work studied the polystyrene-b-poly(ethylene-co-butylene)-b-polystyrene (SEBS) triblock copolymers functionalized by butyl quaternary ammonium (C4Q) groups and alkyl side chains of different ...chain lengths (Cn, n = 0 to 24). The hydrated membrane morphology was modeled by dissipative particle dynamics simulation at hydration levels from 10 to 30. A hydroxide model was devised to characterize the diffusivity of anions under the coarse-grained framework. In general, the ionomers with alkyl side chains provided ion conductivity of a similar level at a lower ion exchange capacity. All hydrated SEBS–C4Q–Cn ionomers showed clear phase separation of the hydrophobic and hydrophilic domains, featuring 18.6 mS/cm to 36.8 mS/cm ion conductivity. The hydrophilic channels expanded as the water content increased, forming more effective ion conductive pathways. Introducing excess alkyl side chains enhanced the nano-segregation, leading to more ordered structures and longer correlation lengths of the aqueous phase. The membrane morphology was controlled by the length of alkyl side-chains as well as their tethering positions. Ionomers with functionalized side chains tethered on the same block resulted in well-connective water networks and higher conductivities. The detailed structural analysis provides synthesis guidelines to fabricate anion exchange membranes with improved performances.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary
Root hair, a special type of tubular‐shaped cell, outgrows from the root epidermal cell and plays important roles in the acquisition of nutrients and water, as well as interactions with ...biotic and abiotic stresses. Studies in the model plant Arabidopsis have revealed that root‐hair initiation and elongation are hierarchically regulated by a group of basic helix−loop−helix (bHLH) transcription factors (TFs). However, knowledge regarding the regulatory pathways of these bHLH TFs in controlling root hair growth remains limited. In this study, RNA‐seq analysis was conducted to profile the transcriptome in the elongating maize root hair and >1000 genes with preferential expression in root hair were identified. A consensus cis‐element previously featured as the potential bHLH‐TF binding sites was present in the regulatory regions for the majority of the root hair‐preferentially expressed genes. In addition, an individual change in ZmLRL5, the highest‐expressed bHLH‐TF in maize root hair resulted in a dramatic reduction in the elongation of root hair, and rendered the growth of root hair hypersensitive to translational inhibition. Moreover, RNA‐seq, yeast‐one‐hybrid and ribosome profile analysis suggested that ZmLRL5 may function as a key player in orchestrating the translational process by directly regulating the expression of translational processes/ribosomal genes during maize root hair growth.
Significance statement
This work describes the identification of genes preferentially expressed in the growing maize root hair. We demonstrate a basic helix−loop−helix transcription factor, Lj‐RHL1‐LIKE 5 (ZmLRL5), that promotes root hair elongation by transcriptionally regulating the expression of genes required for translational processes and continuous protein synthesis. These results pinpoint a prospective mechanism for ZmLRL5 in functioning as a key hub in orchestrating protein synthesis by transcriptional control of translation‐related genes during root hair growth.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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