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Accretion of black holes at near-Eddington or super-Eddington rates represents the most powerful episode driving black hole growth, potentially occurring across various types of objects. However, the physics governing accretion and jet–disk coupling in such states remains unclear, primarily due to the difficulty in detecting associated jets, which may emit extremely weakly or exhibit episodic behavior. Only a few near/super-Eddington systems have demonstrated radio activity, and it remains uncertain whether jets exist and what their properties are in super-Eddington active galactic nuclei (AGNs) and ultraluminous X-ray sources. This uncertainty stems mainly from the complex radio emission mix, which includes contributions from jets, star formation activity, photoionized gas, accretion disk wind, and coronal activity. In this work, we conducted high-resolution, very long baseline interferometry observations to investigate jets in the highly accreting narrow-line Seyfert I system I Zw 1. Our observations successfully revealed small-scale jets (with a linear size of ∼45 pc) at both 1.5 and 5 GHz, based on the high radio brightness temperature, radio morphology, and spectral index distribution. Additionally, the parsec-scale jet observed in I Zw 1 displays a knotted morphology reminiscent of other sources accreting at similar rates. In summary, the high accretion rates and jet properties observed in the AGN I Zw 1 may support the AGN/X-ray binary analogy in this extreme state. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of carbonation treatment on the rebound strength measurement curve of machine-made sand concrete, this study conducted research on the carbonation mechanism sand concrete rebound strength measurement curve through rebound and compressive strength tests using carbonation degree and concrete strength grade as control variables. The results showed that in the short aging period, carbonation treatment had little effect on the compressive strength of manufactured sand concrete but could cause an increase in the rebound value measured by the high-strength and heavy rebound hammers. As the strength grade of the manufactured sand concrete increased, the rebound value measured by both the high-strength and heavy rebound hammers increased accordingly. Compared with the high-strength rebound hammer, the heavy rebound hammer had higher accuracy in detecting the rebound of the carbonated manufactured sand concrete. This study established measurement curves for uncorrected and corrected carbonation depths, among which the accuracy of the corrected carbonation depth measurement curve was higher. At the same time, this measurement curve has been applied to the rebound test of the Pinglu Canal Extra-Large Bridge Project in Guangxi, China, and its practicality and reliability have been verified. [ABSTRACT FROM AUTHOR]

Preventing the accretion of droplets on surfaces is vital and slippery liquid‐infused porous surfaces (SLIPS) have promising application prospects, such as surface self‐cleaning and droplet transportation. In this work, controllable self‐transport of bouncing droplets on ultraslippery surfaces with wedge‐shaped grooves is reported. The impact behaviors of droplets on SLIPS under various impact velocities and diameters are explored, which can be classified as hover, total bounce, partial bounce, Worthington jet, and crush. SLIPS with wedge‐shaped grooves were designed to transport accreted droplets. An energy and transport model is established to explain the impact and self‐transport mechanism, where the Laplace pressure and moving resistance between droplets play a key role. Finally, SLIPS with branched wedge‐shaped grooves were designed for droplet self‐transport and demonstrated advantages. This work provides a general reference for spontaneous motion control of sessile droplets, droplets with initial impacting velocity, or even liquid films. [ABSTRACT FROM AUTHOR]

The Hippo pathway plays crucial roles in governing various biological processes during tumorigenesis and metastasis. Within this pathway, upstream signaling stimuli activate a core kinase cascade, involving MST1/2 and LATS1/2, that subsequently phosphorylates and inhibits the transcriptional co-activators YAP and its paralog TAZ. This inhibition modulates the transcriptional regulation of downstream target genes, impacting cell proliferation, migration, and death. Despite the acknowledged significance of protein kinases in the Hippo pathway, the regulatory influence of protein phosphatases remains largely unexplored. In this study, we conducted the first gain-of-functional screen for protein tyrosine phosphatases (PTPs) regulating the Hippo pathway. Utilizing a LATS kinase biosensor (LATS-BS), a YAP/TAZ activity reporter (STBS-Luc), and a comprehensive PTP library, we identified numerous novel PTPs that play regulatory roles in the Hippo pathway. Subsequent experiments validated PTPN12, a master regulator of oncogenic receptor tyrosine kinases (RTKs), as a previously unrecognized negative regulator of the Hippo pathway effectors, oncogenic YAP/TAZ, influencing breast cancer cell proliferation and migration. In summary, our findings offer valuable insights into the roles of PTPs in the Hippo signaling pathway, significantly contributing to our understanding of breast cancer biology and potential therapeutic strategies. [ABSTRACT FROM AUTHOR]

It is necessary to measure the situation of extinguishing agent concentration along with time in the ground simulation test of helicopter/airplane powerplant. The principle that the different percentage of agent in the air has different flow resistances when these agents passing through some porous plug is used, the relation of agent concentration and flow resistance is researched and confirmed by the calibration. The special extinguishing agent concentration measurement is developed, and used in the ground simulation test of several helicopters. The results show that, the measurement has sensitive response, can reflect the varying situation of extinguishing agent concentration in real-time, and satisfy the requirement of ground simulation test in the fire extinguisher system of helicopter/airplane powerplant.

Cell surface proteins are an important class of biomarkers for fundamental biological research and for disease diagnostics and treatment. In this communication, we report a universal strategy to construct sensors that can achieve rapid imaging of cell surface proteins without any separation by using binding-induced dynamic DNA assembly. As a proof-of-principle, we developed a real-time and wash-free sensor for an important breast cancer biomarker, human epidermal growth factor receptor-2 (HER2). We then demonstrated that this sensor could be used for imaging and sensing HER2 on both fixed and live breast cancer cells. Additionally, we have also incorporated toehold-mediated DNA strand displacement reactions into the HER2 sensor, which allows for reiterating (switching on/off) fluorescence signals for HER2 from breast cancer cells in real-time.

Solid tumours can universally evade contact inhibition of proliferation (CIP), a mechanism halting cell proliferation when cell–cell contact occurs. Merlin, an ERM-like protein, crucially regulates CIP and is frequently deactivated in various cancers, indicating its significance as a tumour suppressor in cancer biology. Despite extensive investigations into Merlin's role in cancer, its lack of intrinsic catalytic activity and frequent conformation changes have made it notoriously challenging to study. To address this challenge, we harnessed innovative luciferase technologies to create and validate a NanoBiT split-luciferase biosensor system in which Merlin is cloned between two split components (LgBiT and SmBiT) of NanoLuc luciferase. This system enables precise quantification of Merlin's conformation and activity both in vitro and within living cells. This biosensor significantly enhances the study of Merlin's molecular functions, serving as a potent tool for exploring its contributions to CIP and tumorigenesis. [ABSTRACT FROM AUTHOR]