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Abstract Background Primary human hepatocytes (PHHs) are highly valuable for drug-metabolism evaluation, liver disease modeling and hepatocyte transplantation. However, their availability is significantly restricted due to limited donor sources, alongside their constrained proliferation capabilities and reduced functionality when cultured in vitro. To address this challenge, we aimed to develop a novel method to efficiently expand PHHs in vitro without a loss of function. Methods By mimicking the in vivo liver regeneration route, we developed a two-step strategy involving the de-differentiation/expansion and subsequent maturation of PHHs to generate abundant functional hepatocytes in vitro. Initially, we applied SiPer, a prediction algorithm, to identify candidate small molecules capable of activating liver regenerative transcription factors, thereby formulating a novel hepatic expansion medium to de-differentiate PHHs into proliferative human hepatic progenitor-like cells (ProHPLCs). These ProHPLCs were then re-differentiated into functionally mature hepatocytes using a new hepatocyte maturation condition. Additionally, we investigated the underlying mechanism of PHHs expansion under our new conditions. Results The novel hepatic expansion medium containing hydrocortisone facilitated the de-differentiation of PHHs into ProHPLCs, which exhibited key hepatic progenitor characteristics and demonstrated a marked increase in proliferation capacity compared to cells cultivated in previously established expansion conditions. Remarkably, these subsequent matured hepatocytes rivaled PHHs in terms of transcriptome profiles, drug metabolizing activities and in vivo engraftment capabilities. Importantly, our findings suggest that the enhanced expansion of PHHs by hydrocortisone may be mediated through the PPARα signaling pathway and regenerative transcription factors. Conclusions This study presents a two-step strategy that initially induces PHHs into a proliferative state (ProHPLCs) to ensure sufficient cell quantity, followed by the maturation of ProHPLCs into fully functional hepatocytes to guarantee optimal cell quality. This approach offers a promising means of producing large numbers of seeding cells for hepatocyte-based applications.

After ischemic stroke (IS), secondary injury is intimately linked to endoplasmic reticulum (ER) stress and body-brain crosstalk. Nonetheless, the underlying mechanism systemic immune disorder mediated ER stress in human IS remains unknown. In this study, 32 candidate ER stress-related genes (ERSRGs) were identified by overlapping MSigDB ER stress pathway genes and DEGs. Three Key ERSRGs (ATF6, DDIT3 and ERP29) were identified using LASSO, random forest, and SVM-RFE. IS patients with different ERSRGs profile were clustered into two groups using consensus clustering and the difference between 2 group was further explored by GSVA. Through immune cell infiltration deconvolution analysis, and middle cerebral artery occlusion (MCAO) mouse scRNA analysis, we found that the expression of 3 key ERSRGs were closely related with peripheral macrophage cell ER stress in IS and this was further confirmed by RT-qPCR experiment. These ERS genes might be helpful to further accurately regulate the central nervous system and systemic immune response through ER stress and have potential application value in clinical practice in IS.

Collaborative programming is being increasingly used to overcome the difficulties of the individual programming process. In this study, we investigated the effect of collaborative perception on cognitive engagement and learning outcomes in collaborative programming. We used a quasi-experimental research to determine the differences in cognitive engagement and learning outcomes of three groups with different levels of collaborative perception. The findings highlight several important conclusions. First, there were significant differences in cognitive engagement and learning outcomes across collaborative perception groups. Students with high levels of collaborative perception demonstrate more comprehensive and diverse cognitive engagement, resulting in higher learning outcomes compared to those with lower perception. Second, students in the low collaborative perception group had more Clarification-Elaboration cognitive connections, and students in the high collaborative perception group had stronger Clarification-Positioning and Clarification-Verification cognitive connections. Third, collaborative perception positively moderated the relationship between cognitive engagement and learning outcomes. In particular, three cognitive engagement, Clarification, Elaboration, and Positioning, had a greater impact on performance when moderated by collaborative perceptions. These findings have practical implications for educators and course designers, emphasizing the importance of considering students' collaborative perception when forming groups and promoting effective collaborative programming.

Abstract Great effort has been made recently to investigate the phase transitions in two-dimensional (2D) magnets while leaving subtle quantification unsolved. Here, we demonstrate the thermal-activated escape in 2D Fe3GeTe2 ferromagnets near the critical point with a quantum magnetometry based on nitrogen-vacancy centers. We observe random switching between the two spin states with auto-correlation time described by the Arrhenius law, where a change of temperature by 0.8 K induces a change of lifetime by three orders of magnitude. Moreover, a large energy difference between the two spin states about 51.3 meV is achieved by a weak out-of-plane magnetic field of 1 G, yielding occupation probability described by Boltzmann’s law. Using these data, we identify all the parameters in the Ginzburg-Landau model. This work provides quantitative description of the phase transition in 2D magnets, which paves the way for investigating the critical fluctuation and even non-equilibrium phase transitions in these 2D materials.

Herpes zoster (HZ) is an infectious disease caused by the reactivation of varicella zoster virus (VZV), with 68% of cases occurring in adults over 50 years of age. HZ/su (Shingrix®) was approved by the Food and Drug Administration in 2017 for the prevention of HZ in individuals ≥ 50 years of age and showed very good protection from HZ. However, due to the use of the adjuvant AS01B, adverse reactions caused by Shingrix are a concern. Aluminum hydroxide is the most commonly used adjuvant and is widely used in a variety of vaccines. We developed a recombinant zoster vaccine (code: LZ901) consisting of a tetramer of VZV glycoprotein E (gE) and a human Fc fusion protein expressed in CHO cells, an immune complex-like molecule that can be adsorbed with an aluminum hydroxide adjuvant. We compared the immunogenicity of LZ901 with that of HZ/su in BALB/c mice. The results showed that LZ901 induced levels of gE-specific IgG antibodies comparable to those induced by HZ/su, and the results of FAMA titers further demonstrated their similar neutralizing antibody abilities. Most importantly, LZ901 induced higher levels of cell-mediated immunity (CMI) (which plays a decisive role in the efficacy of zoster vaccines) than HZ/su in BALB/c mice. The numbers of cytokine-producing T cells in LZ901-vaccinated mice were significantly greater than those in v-vaccinated mice, and the proportions of CD4+ and CD8+ T cells producing at least two types of cytokines in LZ901-vaccinated mice were significantly greater than those in HZ/su-vaccinated mice.

Abstract Electrostatic energy storage capacitors based on dielectrics have attracted much attention due to their wide applications in advanced electrical technology and electronic devices. Generally, high energy density is achieved at a high electric field, while conduction loss becomes nonnegligible, which harms practical applications. Here distinctly suppressed leakage current in BaZr0.5Ti0.5O3‐based films by entropy engineering is realized. With increased entropy, the leakage current density decreases by two orders of magnitude at the electric field of 3 MV cm−1, leading to a markedly improved energy efficiency of 87% at an ultrahigh breakdown strength of 8 MV cm−1 in high‐entropy films. Thereby, a high energy density of 51.9 J cm−3 is achieved. This work demonstrates the effectiveness of entropy engineering in improving the breakdown strength of dielectric films and shows great potential in enhancing the energy storage performance of capacitors.

Abstract Due to the great demand for global energy consumption, electro‐thermal energy interconversion has drawn great attention. Ferroelectrics as promising candidates realize energy conversion through pyroelectric and electrocaloric effects, but their efficiency is not sufficiently high. Herein, using phase‐field simulations, it is demonstrated that superlattices with polar topologies tend to have various polarization behaviors, and the antiferroelectric‐ to paraelectric‐like phase transition induces a large polarization change and thus a high pyroelectric response. In KNbO3/KTaO3 superlattices, the pyroelectric energy conversion has a scaled efficiency of 50% and the equivalent ZT of 7.2, and the electrocaloric cooling temperature reaches 40 K. The operation temperature can be tuned by changing the thickness of the superlattice. The results reveal that oxide superlattices are competitive in energy harvesting and conversion, thus creating new application prospects for polar topologies.

Herein, the (1 − x)(Sr0.7Bi0.2)TiO3–xBi(Mg0.5Hf0.5)O3 (SBT–100xBMH, x = 0.04–0.10) relaxor ferroelectric ceramics are fabricated via the high‐temperature solid‐state reaction method. Dielectric and ferroelectric measurements reveal a typical relaxor characteristic with diffused and frequency‐dependent dielectric peaks. The characteristic Weibull breakdown strength (BDS) of 470 kV cm−1 with satisfied reliability is obtained by DC breakdown measurement. A maximum recoverable energy density of 3.5 J cm−3 with the corresponding energy efficiency of 92% is simultaneously achieved at 380 kV cm−1. The recoverable energy density exhibits minor degradations from ambient temperature to 200 °C with variation below 20%, whereas the energy efficiency is maintained above 90%. In addition, the SBT–8BMH ceramic possesses a fast charge–discharge speed with high discharge power density of 2.9 MW cm−3. All the results make this lead‐free relaxor ferroelectric ceramic a promising potential candidate for high‐temperature energy‐storage capacitor applications.

In a heterodyne receiver, the image can interfere with the desired signal and must be eliminated at the mixing stage. This paper presents a flexible microwave photonic image-reject mixer based on a widely tunable microwave photonic filter (MPF), which is used to select the desired signal and suppress the image. The MPF is realized by using stimulated Brillouin scattering, which offers significant advantages of wideband tunability, high selectivity, and large image rejection. In this work, a theoretical model is established to describe the operation principle of the proposed mixer at first. Then, in the experiment, a 7.8-GHz radio frequency (RF) signal is successfully down-converted to an intermediate frequency signal between 0.2 and 1.5 GHz, with an image rejection of larger than 40 dB. Additionally, when the RF frequency is tuned from 1.8 to 19.8 GHz, the image rejection remains above 40 dB.

A tunable single passband microwave photonic filter (MPF) of overcoming fiber dispersion induced amplitude fading of the microwave passband is proposed and demonstrated. The passband amplitude of the MPF can be kept invariant for different central frequencies. The scheme is realized based on a dual-drive Mach-Zehnder modulator (DDMZM) and a broadband optical source sliced by a delay interferometer. The DDMZM is single-electrode driven and the microwave signal is modulated onto the optical carrier with simultaneous phase and intensity modulation formats. The ratio of the two modulation formats can be controlled by adjusting the bias of DDMZM to compensate the dispersion-induced amplitude fading at any passband of the MPF. In the experiment, the proposed MPF can be tuned between 0 and 30 GHz and the rejection ratio exceeds 30 dB.

Quantum computation provides great speedup over its classical counterpart for certain tasks. Spin system is one of the most important candidates to realize quantum computations. The initialization, readout and quantum gate operations of spin-qubits can be accomplished by advanced spin resonance techniques, which include nuclear magnetic resonance, electron paramagnetic resonance and optically detected magnetic resonance. This review aims to summarize recent experimental progresses in spin-based quantum computing. Preserving quantum states, precise quantum operations, quantum algorithms and quantum simulations on spin systems are reviewed. The fast improvement of quantum technology motivated by quantum computations results in recent progress in spin magnetic resonance in nanoscale. This review also introduces the achievements in nanoscale magnetic resonance with Nitrogen vacancy centers in diamonds.

Axion-like particles (ALPs) are predicted to mediate exotic interactions between spin and mass. We propose an ALP-searching experiment based on the levitated micromechanical oscillator, which is one of the most sensitive sensors for spin-mass forces at a short distance. The proposed experiment tests the spin-mass resonant interaction between the polarized electron spins and a diamagnetically levitated microsphere. By periodically flipping the electron spins, the contamination from nonresonant background forces can be eliminated. The levitated microoscillator can prospectively enhance the sensitivity by nearly 10^{3} times over current experiments for ALPs with mass in the range 4 meV to 0.4 eV.

The continuous spontaneous localization (CSL) model predicts a tiny break of energy conservation via a weak stochastic force acting on physical systems, which triggers the collapse of the wave function. Mechanical oscillators are a natural way to test such a force; in particular, a levitated micromechanical oscillator has been recently proposed to be an ideal system. We report a proof-of-principle experiment with a micro-oscillator generated by a microsphere diamagnetically levitated in a magnetogravitational trap under high vacuum. Due to the ultralow mechanical dissipation, the oscillator provides a new upper bound on the CSL collapse rate, which gives an improvement of two orders of magnitude over the previous bounds in the same frequency range, and partially reaches the enhanced collapse rate suggested by Adler. Although being performed at room temperature, our experiment has already exhibited advantages over those operating at low temperatures. Our results experimentally show the potential for a magnetogravitational levitated mechanical oscillator as a promising method for testing the collapse model. Further improvements in cryogenic experiments are discussed.

Fast and accurate quantum operations of a single spin in room-temperature solids are required in many modern scientific areas, for instance in quantum information, quantum metrology, and magnetometry. However, the accuracy is limited if the Rabi frequency of the control is comparable with the transition frequency of the qubit due to the breakdown of the rotating wave approximation (RWA). We report here an experimental implementation of a control method based on quantum optimal control theory which does not suffer from such restriction. We demonstrate the most commonly used single qubit rotations, i.e. $\pi /2$ - and π -pulses, beyond the RWA regime with high fidelity $F_{\pi /2}^{{\rm exp} }=0.95\pm 0.01$ and $F_{\pi }^{{\rm exp} }=0.99\pm 0.016$ , respectively. They are in excellent agreement with the theoretical predictions, $F_{\pi /2}^{{\rm theory}}=0.9545$ and $F_{\pi }^{{\rm theory}}=0.9986$ . Furthermore, we perform two basic magnetic resonance experiments both in the rotating and the laboratory frames, where we are able to deliberately ‘switch’ between the frames, to confirm the robustness of our control method. Our method is general, hence it may immediately find its wide applications in magnetic resonance, quantum computing, quantum optics, and broadband magnetometry.

We demonstrate quantum coherent control of single electronic spins in a nitron-vacancy center in diamond by exploiting and implementing the general concept of Landau-Zener-Stückelberg interferometry at room temperature. The interferometry manipulates an effective two-level system of electronic spins which are coupled to the nearby ^{14}N nuclear spin in the nitron-vacancy center as well as the nuclear spin bath in the diamond. With a microwave field to control the energy gap between the two levels and an AC field as the time-dependent driving field in Landau-Zener-Stückelberg interferometry, the interference pattern can be generated and controlled by controlling a number of parameters in the fields, corresponding to coherent control of the state of the electronic spins. In particular, the interference pattern is observed oscillating as a function of the frequency of the microwave field. Decays in the visibility of the interference pattern are also observed and well explained by numerical simulation which takes into account the thermal fluctuations arising from the nuclear bath. Therefore, our work also demonstrates that Landau-Zener-Stückelberg interferometry can be used for probing decoherence processes of electronic spins.

Periaqueductal gray (PAG), an integration center for neuronal signals, is located in the midbrain and regulates multiple physiological and pathological behaviors, including pain, defensive and aggressive behaviors, anxiety and depression, cardiovascular response, respiration, and sleep-wake behaviors. Due to the different neuroanatomical connections and functional characteristics of the four functional columns of PAG, different subregions of PAG synergistically regulate various instinctual behaviors. In the current review, we summarized the role and possible neurobiological mechanism of different subregions of PAG in the regulation of pain, defensive and aggressive behaviors, anxiety, and depression from the perspective of the up-down neuronal circuits of PAG. Furthermore, we proposed the potential clinical applications of PAG. Knowledge of these aspects will give us a better understanding of the key role of PAG in physiological and pathological behaviors and provide directions for future clinical treatments. [ABSTRACT FROM AUTHOR]

How to illuminate dark matter has become the foremost open question in fundamental science nowadays, which is of great significance in understanding the laws of nature. Exploring exotic interactions beyond the standard model is one of the essential approaches to searching for dark matter particles. Although it has been explored in a variety of lab-scale and tabletop-scale setups over the past years, no such interactions have been observed, and improving the sensitivity significantly becomes of paramount importance, but challenging. Here, we formulate the conception of a spin-mechanical quantum chip compatible with scalable on-chip detectors. Utilizing the prototype chip realized by the integration of a mechanical resonator and a diamond with single nitrogen vacancy at the microscale, the constraints of spin-velocity-dependent interactions have been improved by two orders of magnitude, where there is no evidence for new bosons in the force range below 100 nm, i.e., in the rest-mass window of 2–10 electronvolts. Based on the proof-of-principle experiment, this promising chip can be scaled up to meet the requirements of searching for exotic interactions at preeminent sensitivity. Low-cost and high-yield chip-scale setups will accelerate the process of dark matter exploration, providing a path toward on-chip fundamental physics experiments. [ABSTRACT FROM AUTHOR]