A spin-mechanical quantum chip for exploring exotic interactions.

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.

Identification of endoplasmic reticulum stress genes in human stroke based on bioinformatics and machine learning.

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.

Single-Shot Readout of a Solid-State Electron Spin Qutrit.

Quantum systems usually feature a rich multilevel structure with promising resources for developing superior quantum technologies compared with their binary counterpart. Single-shot readout of these high-dimensional quantum systems is essential for exploiting their potential. Although there have been various high-spin systems, the single-shot readout of the overall state of high-spin systems remains a challenging issue. Here we demonstrate a reliable single-shot readout of spin qutrit state in a low-temperature solid-state system utilizing a binary readout scheme. We achieve a single-shot readout of an electron spin qutrit associated with a single nitrogen-vacancy center in diamond with an average fidelity of 87.80%. We use this spin qutrit system to verify quantum contextuality, a fundamental test of quantum mechanics. We observe a violation of the noncontextual hidden variable inequality with the developed single-shot readout in contrast to the conventional binary readout. These results pave the way for developing quantum information processing based on spin qutrits.

99.92%-Fidelity cnot Gates in Solids by Noise Filtering.

Inevitable interactions with the reservoir largely degrade the performance of entangling gates, which hinders practical quantum computation from coming into existence. Here, we experimentally demonstrate a 99.920(7)%-fidelity controlled-not gate by suppressing the complicated noise in a solid-state spin system at room temperature. We found that the fidelity limited at 99% in previous works results from considering only static classical noise, and, thus, in this work, a complete noise model is constructed by also considering the time dependence and the quantum nature of the spin bath. All noises in the model are dynamically corrected by an exquisitely designed shaped pulse, giving the resulting error below 10^{-4}. The residual gate error is mainly originated from the longitudinal relaxation and the waveform distortion that can both be further reduced technically. Our noise-resistant method is universal and will benefit other solid-state spin systems.

Negative cooperativity between Gemin2 and RNA provides insights into RNA selection and the SMN complex's release in snRNP assembly.

The assembly of snRNP cores, in which seven Sm proteins, D1/D2/F/E/G/D3/B, form a ring around the nonameric Sm site of snRNAs, is the early step of spliceosome formation and essential to eukaryotes. It is mediated by the PMRT5 and SMN complexes sequentially in vivo. SMN deficiency causes neurodegenerative disease spinal muscular atrophy (SMA). How the SMN complex assembles snRNP cores is largely unknown, especially how the SMN complex achieves high RNA assembly specificity and how it is released. Here we show, using crystallographic and biochemical approaches, that Gemin2 of the SMN complex enhances RNA specificity of SmD1/D2/F/E/G via a negative cooperativity between Gemin2 and RNA in binding SmD1/D2/F/E/G. Gemin2, independent of its N-tail, constrains the horseshoe-shaped SmD1/D2/F/E/G from outside in a physiologically relevant, narrow state, enabling high RNA specificity. Moreover, the assembly of RNAs inside widens SmD1/D2/F/E/G, causes the release of Gemin2/SMN allosterically and allows SmD3/B to join. The assembly of SmD3/B further facilitates the release of Gemin2/SMN. This is the first to show negative cooperativity in snRNP assembly, which provides insights into RNA selection and the SMN complex's release. These findings reveal a basic mechanism of snRNP core assembly and facilitate pathogenesis studies of SMA.

Looking at MOOC discussion data to uncover the relationship between discussion pacings, learners' cognitive presence and learning achievements.

The MOOCs (Massive Open Online Courses) forum carries rich discussion data that contains multi-level cognition-related behavior patterns, which brings the potential for an in-depth investigation into the development trend of the group and individual cognitive presence in discourse interaction. This paper describes a study conducted in the context of an introductory astronomy course on the Chinese MOOCs platform, examining the relationship between discussion pacings (i.e., instructor-paced or learner-paced discussion), cognitive presence, and learning achievements. Using content analysis, lag sequential analysis, logistic regression, and grouped regression approaches, the study analysed the online discussion data collected from the Astronomy Talk course involving 2603 participants who contributed 24,018 posts. The findings of the study demonstrated the significant cognitive sequential patterns, and revealed the significant differences in the distribution of cognitive presence with different discussion pacings and learning achievement groups, respectively. Moreover, we found that the high-achieving learners were mostly in the exploration, integration, and resolution phase, and learner-paced discussion had a greater moderating effect on the relationship between cognitive presence and learning achievements. Based on the findings and discussion, suggestions for improving the learners' cognitive presence and learning achievements in the MOOC environment are discussed.

Nucleo-cytoplasmic RNA distribution responsible for maintaining neuroinflammatory microenvironment.

Subcellular localization of transcripts is highly associated with regulation of gene expression, synthesis of protein, and also the development of the human brain cortex. Although many mechanisms are prevalent in the occurrence of neuroinflammation, the mechanisms based on differences in subcellular localization of transcripts have not been explored. To characterize the dynamic profile of nuclear and cytoplasmic transcripts during the progress of haemorrhage-induced neuroinflammation, we isolated nucleo-cytoplasmic RNA fractions of oxyhaemoglobin (oxy-Hb) treated microglia cells and sequenced both fractions. We discovered that cytoplasmic retained genes were the major forces to maintain the neuroinflammatory microenvironment with 10 hub genes and 40 conserved genes were identified. Moreover, antisense RNA Gm44096 and lincRNA Gm47270, which co-expressed with a crowd of inflammatory genes in the cytoplasm, were discovered as regulatory strategies for sustaining the neuroinflammatory microenvironment. Thus, our study provides a new perspective on understanding haemorrhage-induced neuroinflammation and also reveals a mechanism of lncRNA responsible for maintaining the neuroinflammatory microenvironment.

SH3PXD2A-AS1/miR-330-5p/UBA2 ceRNA network mediates the progression of colorectal cancer through regulating the activity of the Wnt/ß-catenin signaling pathway.

Long non-coding RNAs have important roles in the occurrence and progression of various cancers. However, the molecular mechanism of lncRNAs in colorectal cancer (CRC) is not well illustrated. Thus, we used bioinformatics methods to find potential lncRNAs associated with CRC progression, and chose SH3PXD2A-AS1 as a candidate for further analysis. The roles of SH3PXD2A-AS1 in CRC cells were determined by CCK-8, transwell invasion, wound healing and flow cytometry assays. Besides, we established the CRC tumor models in nude mice to study the effect of SH3PXD2A-AS1 on the tumor growth. Based on the ceRNA hypothesis, we used miRDB and miRTarBase websites to identify the SH3PXD2A-AS1-related ceRNA regulatory network, and measured the roles of this network in CRC cells. The results revealed that the expression profiles of SH3PXD2A-AS1 from GEO and TCGA databases showed an aberrant high level in CRC tissues compared with colorectal normal tissues. SH3PXD2A-AS1 over-expression was also found in CRC cells. SH3PXD2A-AS1 knockdown inhibited the CRC cellular proliferation, invasion and migration but induced apoptosis. Besides, SH3PXD2A-AS1 knockdown also suppressed the growth of CRC tumors. Furthermore, SH3PXD2A-AS1 could function as a ceRNA of miR-330-5p. Additionally, UBA2 was proved to be a target gene of miR-330-5p. Moreover, SH3PXD2A-AS1 knockdown downregulated UBA2 expression through sponging miR-330-5p to inactivate the Wnt/ß-catenin signaling pathway, thereby inhibiting the cell growth and promoting apoptosis. Therefore, the SH3PXD2A-AS1/miR-330-5p/UBA2 network could regulate the progression of CRC through the Wnt/ß-catenin pathway. These findings offer new sights for understanding the pathogenesis of CRC and provide potential biomarkers for CRC treatment.

Transcription factor CaNAC1 regulates low-temperature-induced phospholipid degradation in green bell pepper.

Phospholipids constitute the main component of biomembranes. During low-temperature storage and transportation of harvested bell peppers (Capsicum annuum), chilling injury participates in their decay. A primary cause of this chilling injury is phospholipid degradation. In this study, three genes encoding phospholipase D (PLD) were identified from bell peppers and their activities were examined under cold stress. Low temperature (4 °C) induced strong accumulation of the CaPLDα4 transcript, suggesting that it is associated with the phenomenon of phospholipid degradation and destruction of cell membranes. Low temperature also significantly induced increased amounts of NAM-ATAF1/2-CUC2 (NAC) domain transcription factors. CaNAC1 was found to interact with the promoter of CaPLD4 in a yeast one-hybrid screen. Electrophoretic mobility shift and ß-glucuronidase reporter assays demonstrated that CaNAC1 binds to the CTGCAG motif in the CaPLDα4 promoter, thereby activating its transcription and controlling phospholipid degradation. The ubiquitination sites of the CaNAC1 protein were characterized by liquid chromatography-tandem mass spectrometry. We conclude that CaNAC1 is a transcriptional activator of CaPLDα4 and suggested that it participates in the degradation of membrane lipids in bell peppers when they are stored at low temperature.

Direct Measurement of Topological Numbers with Spins in Diamond.

Topological numbers can characterize the transition between different topological phases, which are not described by Landau's paradigm of symmetry breaking. Since the discovery of the quantum Hall effect, more topological phases have been theoretically predicted and experimentally verified. However, it is still an experimental challenge to directly measure the topological numbers of various predicted topological phases. In this Letter, we demonstrate quantum simulation of topological phase transition of a quantum wire (QW), by precisely modulating the Hamiltonian of a single nitrogen-vacancy (NV) center in diamond. Deploying a quantum algorithm of finding eigenvalues, we reliably extract both the dispersion relations and topological numbers. This method can be further generalized to simulate more complicated topological systems.

Experimental Realization of High-Efficiency Counterfactual Computation.

Counterfactual computation (CFC) exemplifies the fascinating quantum process by which the result of a computation may be learned without actually running the computer. In previous experimental studies, the counterfactual efficiency is limited to below 50%. Here we report an experimental realization of the generalized CFC protocol, in which the counterfactual efficiency can break the 50% limit and even approach unity in principle. The experiment is performed with the spins of a negatively charged nitrogen-vacancy color center in diamond. Taking advantage of the quantum Zeno effect, the computer can remain in the not-running subspace due to the frequent projection by the environment, while the computation result can be revealed by final detection. The counterfactual efficiency up to 85% has been demonstrated in our experiment, which opens the possibility of many exciting applications of CFC, such as high-efficiency quantum integration and imaging.

Exploring the influence of students' perceptions of face-to-face collaboration on cognitive engagement and learning outcomes in collaborative programming.

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.

Bromodomain-containing protein 4 knockdown promotes neuronal ferroptosis in a mouse model of subarachnoid hemorrhage.

Neuronal cell death is a common outcome of multiple pathophysiological processes and a key factor in neurological dysfunction after subarachnoid hemorrhage. Neuronal ferroptosis in particular plays an important role in early brain injury. Bromodomain-containing protein 4, a member of the bromo and extraterminal domain family of proteins, participated in multiple cell death pathways, but the mechanisms by which it regulates ferroptosis remain unclear. The primary aim of this study was to investigate how bromodomain-containing protein 4 affects neuronal ferroptosis following subarachnoid hemorrhage in vivo and in vitro. Our findings revealed that endogenous bromodomain-containing protein 4 co-localized with neurons, and its expression was decreased 48 hours after subarachnoid hemorrhage of the cerebral cortex in vivo. In addition, ferroptosis-related pathways were activated in vivo and in vitro after subarachnoid hemorrhage. Targeted inhibition of bromodomain-containing protein 4 in neurons increased lipid peroxidation and intracellular ferrous iron accumulation via ferritinophagy and ultimately led to neuronal ferroptosis. Using cleavage under targets and tagmentation analysis, we found that bromodomain-containing protein 4 enrichment in the Raf-1 promoter region decreased following oxyhemoglobin stimulation in vitro. Furthermore, treating bromodomain-containing protein 4-knockdown HT-22 cell lines with GW5074, a Raf-1 inhibitor, exacerbated neuronal ferroptosis by suppressing the Raf-1/ERK1/2 signaling pathway. Moreover, targeted inhibition of neuronal bromodomain-containing protein 4 exacerbated early and long-term neurological function deficits after subarachnoid hemorrhage. Our findings suggest that bromodomain-containing protein 4 may have neuroprotective effects after subarachnoid hemorrhage, and that inhibiting ferroptosis could help treat subarachnoid hemorrhage.

Comparison of the Immunogenicity of the LZ901 Vaccine and HZ/su Vaccine in a Mouse Model.

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.

Sub-nanotesla sensitivity at the nanoscale with a single spin.

High-sensitivity detection of the microscopic magnetic field is essential in many fields. Good sensitivity and high spatial resolution are mutually contradictory in measurement, which is quantified by the energy resolution limit. Here we report that a sensitivity of 0.5 nT/[Formula: see text] at the nanoscale is achieved experimentally by using nitrogen-vacancy defects in diamond with depths of tens of nanometers. The achieved sensitivity is substantially enhanced by integrating with multiple quantum techniques, including real-time-feedback initialization, dynamical decoupling with shaped pulses and repetitive readout via quantum logic. Our magnetic sensors will shed new light on searching new physics beyond the standard model, investigating microscopic magnetic phenomena in condensed matters, and detection of life activities at the sub-cellular scale.

Apolipoprotein E Polymorphism Impacts White Matter Injury Through Microglial Phagocytosis After Experimental Subarachnoid Hemorrhage.

Apolipoprotein E (apoE, protein; APOE, gene), divided into three alleles of E2, E3 and E4 in humans, is associated with the progression of white matter lesion load. However, mechanism evidence has not been reported regarding the APOE genotype in early white matter injury (WMI) under subarachnoid hemorrhage (SAH) conditions. In the present study, we investigated the effects of APOE gene polymorphisms, by constructing microglial APOE3 and APOE4-specific overexpression, on WMI and underlying mechanisms of microglia phagocytosis in a mice model of SAH. A total of 167 male C57BL/6J mice (weight 22-26 g) were used. SAH and bleeding environment were induced by endovascular perforation in vivo and oxyHb in vitro, respectively. Multi-technology approaches, including immunohistochemistry, high throughput sequencing, gene editing for adeno-associated viruses, and several molecular biotechnologies were used to validate the effects of APOE polymorphisms on microglial phagocytosis and WMI after SAH. Our results revealed that APOE4 significantly aggravated the WMI and decreased neurobehavioral function by impairing microglial phagocytosis after SAH. Indicators negatively associated with microglial phagocytosis increased like CD16, CD86 and the ratio of CD16/CD206, while the indicators positively associated with microglial phagocytosis decreased like Arg-1 and CD206. The increased ROS and aggravating mitochondrial damage demonstrated that the damaging effects of APOE4 in SAH may be associated with microglial oxidative stress-dependent mitochondrial damage. Inhibiting mitochondrial oxidative stress by Mitoquinone (mitoQ) can enhance the phagocytic function of microglia. In conclusion, anti-oxidative stress and phagocytosis protection may serve as promising treatments in the management of SAH.

Different expression patterns of CEACAM1 and its impacts on angiogenesis in gastric nonneoplastic and neoplastic lesions.

OBJECTIVE: This study was designed to investigate the expression patterns of CEACAM1 and its relationship with angiogenesis in nonneoplastic and neoplastic gastric lesions. METHODS: CEACAM1 and TGF-ß expression was detected by immunohistochemical staining and dual-labeling immunohistochemical staining in neoplastic and nonneoplastic lesions. MVD-CD31 and MVD-CD105 were counted in CEACAM1-positive areas by dual-labeling immunohistochemistry. RESULTS: There was no expression of CEACAM1 in normal gastric mucosa. In IM and GIN, CEACAM1 was mainly expressed with membranous pattern. CEACAM1 was expressed with membranous pattern in well-differentiated adenocarcinoma, with cytoplasmic pattern in poorly differentiated adenocarcinoma, and with cytoplasmic and membranous pattern mixed together in intermediately adenocarcinoma. The expression patterns of CEACAM1 showed a significant difference (P < 0.05) in nonneoplastic and neoplastic lesions. Coexpression of CEACAM1 and TGF-ß was elevated and significantly different from nonneoplastic to neoplastic lesions (P < 0.05). Moreover, CEACAM1 and TGF-ß coexpression were related to carcinoma progression (r = 0.35; P < 0.05). MVD-CD31 and MVD-CD105 showed significant differences from nonneoplastic to neoplastic lesions (P < 0.05). CONCLUSIONS: CEACAM1 has different expression patterns in nonneoplastic and neoplastic lesions. The coexpression of CEACAM1 and TGF-ß increased from nonneoplastic to neoplastic lesions and may be related with tumor progression via promoting tumorous angiogenesis.

Coherence-protected quantum gate by continuous dynamical decoupling in diamond.

In order to achieve reliable quantum-information processing results, we need to protect quantum gates along with the qubits from decoherence. Here we demonstrate experimentally on a nitrogen-vacancy system that by using a continuous-wave dynamical decoupling method, we might not only prolong the coherence time by about 20 times but also protect the quantum gates for the duration of the controlling time. This protocol shares the merits of retaining the superiority of prolonging the coherence time and at the same time easily combining with quantum logic tasks. This method can be useful in tasks where the duration of quantum controlling exceeds far beyond the dephasing time.

Excellent Energy Storage Properties Achieved in Sodium Niobate-Based Relaxor Ceramics through Doping Tantalum.

Lead-free relaxor ferroelectric ceramics are potential for energy storage applications due to their comprehensive energy storage properties. However, the energy efficiency of many relaxor ceramics is not high enough, leading to high Joule heat during the charge-discharge cycles, thus lowering their energy storage performance. In this work, tantalum (Ta) dopants were introduced into sodium niobate-based relaxor ceramics to improve the resistivity and energy efficiency. The leakage current was reduced by Ta doping, especially at the high electric field. The enhanced resistivity is attributed to the increased bandgap induced by Ta doping. The impedance spectroscopy shows that both the grain and grain boundary resistivities are improved in the high temperature region. As a result, the optimal recoverable energy density and energy efficiency are 6.5 J/cm3 and 94% at 450 kV/cm, respectively. In addition, the energy storage properties exhibit satisfactory temperature stability and cycling reliability. All these merits demonstrate that the Ta modified sodium niobate-based relaxor ceramic a potential candidate for high-power energy storage applications.

Beating the standard quantum limit under ambient conditions with solid-state spins.

The use of entangled sensors improves the precision limit from the standard quantum limit (SQL) to the Heisenberg limit. Most previous experiments beating the SQL are performed on the sensors that are well isolated under extreme conditions. Here, we demonstrate a sub-SQL interferometer at ambient conditions by using a multispin system, namely, the nitrogen-vacancy (NV) defect in diamond. We achieve two-spin interference with a phase sensitivity of 1.79 ± 0.06 dB beyond the SQL and three-spin interference with a phase sensitivity of 2.77 ± 0.10 dB. Besides, a magnetic sensitivity of 0.87 ± 0.09 dB beyond the SQL is achieved by two-spin interference for detecting a real magnetic field. Particularly, the deterministic and joint initialization of NV negative state, NV electron spin, and two nuclear spins is realized at room temperature. The techniques used here are of fundamental importance for quantum sensing and computing, and naturally applicable to other solid-state spin systems.