Selective binding and periodic arrangement of magic boron clusters on monolayer borophene.

The synthesis and characterization of small boron clusters with unique size and regular arrangement are crucial for boron chemistry and two-dimensional borophene materials. In this study, together with theoretical calculations, the joint molecular beam epitaxy and scanning tunneling microscopy experiments achieve the formation of unique B5 clusters on monolayer borophene (MLB) on a Cu(111) surface. The B5 clusters tend to selectively bind to specific sites of MLB with covalent boron-boron bonds in the periodic arrangement, which can be ascribed to the charge distribution and electron delocalization character of MLB and also prohibits nearby co-adsorption of B5 clusters. Furthermore, the close-packed adsorption of B5 clusters would facilitate the synthesis of bilayer borophene, exhibiting domino effect-like growth mode. The successful growth and characterization of uniform boron clusters on a surface enrich the boron-based nanomaterials and reveal the essential role of small clusters during the growth of borophene.

Directional electronic tuning of Ni nanoparticles by interfacial oxygen bridging of support for catalyzing alkaline hydrogen oxidation.

Metallic nickel (Ni) is a promising candidate to substitute Pt-based catalysts for hydrogen oxidation reaction (HOR), but huge challenges still exist in precise modulation of the electronic structure to boost the electrocatalytic performances. Herein, we present the use of single-layer Ti3C2Tx MXene to deliberately tailor the electronic structure of Ni nanoparticles via interfacial oxygen bridges, which affords Ni/Ti3C2Tx electrocatalyst with exceptional performances for HOR in an alkaline medium. Remarkably, it shows a high kinetic current of 16.39 mA cmdisk-2 at the overpotential of 50 mV for HOR [78 and 2.7 times higher than that of metallic Ni and Pt/C (20%), respectively], also with good durability and CO antipoisoning ability (1,000 ppm) that are not available for conventional Pt/C (20%) catalyst. The ultrahigh conductivity of single-layer Ti3C2Tx provides fast transmission of electrons for Ni nanoparticles, of which the uniform and small sizes endow them with high-density active sites. Further, the terminated -O/-OH functional groups on Ti3C2Tx directionally capture electrons from Ni nanoparticles via interfacial Ni-O bridges, leading to obvious electronic polarization. This could enhance the Nids-O2p interaction and weaken Nids-H1s interaction of Ni sites in Ni/Ti3C2Txenabling a suitable H-/OH-binding energy and thus enhancing the HOR activity.

Kurarinone alleviated Parkinson's disease via stabilization of epoxyeicosatrienoic acids in animal model.

Parkinson's disease (PD) is one of the most common neurodegenerative disorders and is characterized by loss of dopaminergic neurons in the substantia nigra (SN), causing bradykinesia and rest tremors. Although the molecular mechanism of PD is still not fully understood, neuroinflammation has a key role in the damage of dopaminergic neurons. Herein, we found that kurarinone, a unique natural product from Sophora flavescens, alleviated the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced behavioral deficits and dopaminergic neurotoxicity, including the losses of neurotransmitters and tyrosine hydroxylase (TH)-positive cells (SN and striatum [STR]). Furthermore, kurarinone attenuated the MPTP-mediated neuroinflammation via suppressing the activation of microglia involved in the nuclear factor kappa B signaling pathway. The proteomics result of the solvent-induced protein precipitation and thermal proteome profiling suggest that the soluble epoxide hydrolase (sEH) enzyme, which is associated with the neuroinflammation of PD, is a promising target of kurarinone. This is supported by the increase of plasma epoxyeicosatrienoic acids (sEH substrates) and the decrease of dihydroxyeicosatrienoic acids (sEH products), and the results of in vitro inhibition kinetics, surface plasmon resonance, and cocrystallization of kurarinone with sEH revealed that this natural compound is an uncompetitive inhibitor. In addition, sEH knockout (KO) attenuated the progression of PD, and sEH KO plus kurarinone did not further reduce the protection of PD in MPTP-induced PD mice. These findings suggest that kurarinone could be a potential natural candidate for the treatment of PD, possibly through sEH inhibition.

DNMT3a-mediated methylation of PPARγ promote intervertebral disc degeneration by regulating the NF-κB pathway.

Intervertebral disc degeneration (IVDD) is a common chronic musculoskeletal disease that causes chronic low back pain and imposes an immense financial strain on patients. The pathological mechanisms underlying IVDD have not been fully elucidated. The development of IVDD is closely associated with abnormal epigenetic changes, suggesting that IVDD progression may be controlled by epigenetic mechanisms. Consequently, this study aimed to investigate the role of epigenetic regulation, including DNA methyltransferase 3a (DNMT3a)-mediated methylation and peroxisome proliferator-activated receptor γ (PPARγ) inhibition, in IVDD development. The expression of DNMT3a and PPARγ in early and late IVDD of nucleus pulposus (NP) tissues was detected using immunohistochemistry and western blotting analyses. Cellularly, DNMT3a inhibition significantly inhibited IL-1ß-induced apoptosis and extracellular matrix (ECM) degradation in rat NP cells. Pretreatment with T0070907, a specific inhibitor of PPARγ, significantly reversed the anti-apoptotic and ECM degradation effects of DNMT3a inhibition. Mechanistically, DNMT3a modified PPARγ promoter hypermethylation to activate the nuclear factor-κB (NF-κB) pathway. DNMT3a inhibition alleviated IVDD progression. Conclusively, the results of this study show that DNMT3a activates the NF-κB pathway by modifying PPARγ promoter hypermethylation to promote apoptosis and ECM degradation. Therefore, we believe that the ability of DNMT3a to mediate the PPARγ/NF-κB axis may provide new ideas for the potential pathogenesis of IVDD and may become an attractive target for the treatment of IVDD.

Antibody-secreting cells as a source of NR1-IgGs in N-methyl-D-aspartate receptor-antibody encephalitis.

BACKGROUND: The pathogenicity of NR1-IgGs in N-methyl-D-aspartate receptor (NMDAR)-antibody encephalitis is known, but the immunobiological mechanisms underlying their production remain unclear. METHODS: For the first time, we explore the origin of NR1-IgGs and evaluate the contribution of B-cells to serum NR1-IgGs levels. Peripheral blood mononuclear cells (PBMCs) were obtained from patients and healthy controls (HCs). Naïve, unswitched memory (USM), switched memory B cells (SM), antibody-secreting cells (ASCs), and PBMC depleted of ASCs were obtained by fluorescence-activated cell sorting and cultured in vitro. RESULTS: For some patients, PBMCs spontaneously produced NR1-IgGs. Compared to the patients in PBMC negative group, the positive group had higher NR1-IgG titers in cerebrospinal fluid and Modified Rankin scale scores. The proportions of NR1-IgG positive wells in PBMCs cultures were correlated with NR1-IgGs titers in serum and CSF. The purified ASCs, SM, USM B cells produced NR1-IgGs in vitro. Compared to the patients in ASCs negative group, the positive group exhibited a worse response to second-line IT at 3-month follow-up. Naïve B cells also produce NR1-IgGs, implicating that NR1-IgGs originate from naïve B cells and a pre-germinal centres defect in B cell tolerance checkpoint in some patients. For HCs, no NR1-IgG from cultures was observed. PBMC depleted of ASCs almost eliminated the production of NR1-IgGs. CONCLUSIONS: These collective findings suggested that ASCs might mainly contribute to the production of peripheral NR1-IgG in patients with NMDAR-antibody encephalitis in the acute phase. Our study reveals the pathogenesis and helps develop tailored treatments (eg, anti-CD38) for NMDAR-antibody encephalitis.

Six-Coordinated CoII Single-Molecule Magnets: Synthetic Strategy, Structure and Magnetic Properties.

The pursuit of molecule-based magnetic memory materials contributes significantly to high-density information storage research in the frame of the ongoing information technologies revolution. Remarkable progress has been achieved in both transition metal (TM) and lanthanide based single-molecule magnets (SMMs). Notably, six-coordinated CoII SMMs hold particular research significance owing to the economic and abundant nature of 3d TM ions compared to lanthanide ions, the substantial spin-orbit coupling of CoII ions, the potential for precise control over coordination geometry, and the air-stability of coordination-saturated structures. In this review, we will summarize the progress made in six-coordinated CoII SMMs, organized by their coordination geometry and molecular structure similarity. Valuable insights, principles, and new mechanism gleaned from this research and remaining issues that need to be addressed will also be discussed to guide future optimization.

Switching from eltrombopag to hetrombopag in patients with primary immune thrombocytopenia: a post-hoc analysis of a multicenter, randomized phase III trial.

While studies have explored the feasibility of switching between various thrombopoietin receptor agonists in treating immune thrombocytopenia (ITP), data on the switching from eltrombopag to hetrombopag remains scarce. This post-hoc analysis of a phase III hetrombopag trial aimed to assess the outcomes of ITP patients who switched from eltrombopag to hetrombopag. In the original phase III trial, patients initially randomized to the placebo group were switched to eltrombopag. Those who completed this 14-week eltrombopag were eligible to switch to a 24-week hetrombopag. Treatment response, defined as a platelet count of ≥ 50 × 109/L, and safety were evaluated before and after the switch. Sixty-three patients who completed the 14-week eltrombopag and switched to hetrombopag were included in this post-hoc analysis. Response rates before and after the switch were 66.7% and 88.9%, respectively. Among those with pre-switching platelet counts below 30 × 109/L, eight out of 12 patients (66.7%) responded, while eight out of nine patients (88.9%) with pre-switching platelet counts between 30 × 109/L and 50 × 109/L responded post-switching. Treatment-related adverse events were observed in 50.8% of patients during eltrombopag treatment and 38.1% during hetrombopag treatment. No severe adverse events were noted during hetrombopag treatment. Switching from eltrombopag to hetrombopag in ITP management appears to be effective and well-tolerated. Notably, hetrombopag yielded high response rates, even among patients who had previously shown limited response to eltrombopag. However, these observations need to be confirmed in future trials.

Bottom-Up Construction of Rhombic Lamellar CoNi-MOFs for the Electrochemical Sensing of H2S.

Lamellar metal-organic frameworks (MOFs) have attracted significant attention in the field of electrochemical sensing due to their abundant open active sites and specific electron conductivity. Herein, by employing a bottom-up synthesis strategy, rhombic lamellar heterometallic CoNi-MOFs with varying thicknesses are constructed. This is achieved by using 4-methylpyridine as a capping agent based on the (4,6)-linked Co2(azpy)2(bptc) (azpy = 4,4'-azopyridine, bptc = 3,3',5,5'-biphenyltetracarboxylic acid) structure with a fsc topology and by introducing Ni species simultaneously. To mitigate sulfur deposition on electrodes, the triple pulse amperometry (TPA) method is employed. Among the synthesized lamellar CoNi-MOFs, lamellar CoNi-MOF-3 with the minimum thickness exhibits an optimal electrochemical sensing performance toward hydrogen sulfide, with a sensitivity of 119.3 µA·mM-1·cm-2 in the linear range of 2-2000 µM. This study pioneers a new approach to the controlled construction and electrochemical activity modification of lamellar MOF materials.

Construction of a Bifunctional Redox-Site Conjugated Covalent-Organic Framework for Photoinduced Precision Trapping of Uranyl Ions.

The performance of covalent-organic frameworks (COFs) for the photocatalytic extraction of uranium is greatly limited by the number of adsorption sites. Herein, inspired by electronegative redox reactions, we designed a nitrogen-oxygen rich pyrazine connected COF (TQY-COF) with multiple redox sites as a platform for extracting uranium via combining superaffinity and enhanced photoinduction. The preorganized bisnitrogen-bisoxygen donor configuration on TQY-COF is entirely matched with the typical geometric coordination of hexavalent uranyl ions, which demonstrates high affinity (tetra-coordination). In addition, the presence of the carbonyl group and pyrazine ring effectively stores and controls electron flow, which efficaciously facilitates the separation of e-/h+ and enhances photocatalytic performance. The experimental results show that TQY-COF removes up to 99.8% of uranyl ions from actual uranium mine wastewater under the light conditions without a sacrificial agent, and the separation coefficient reaches 1.73 × 106 mL g-1 in the presence of multiple metal ions, which realizes the precise separation in the complex environment. Importantly, DFT calculations further elucidate the coordination mechanism of uranium and demonstrate the necessity of the presence of N/O atoms in the photocatalytic adsorption of uranium.

Anthropocene 129I Record in the Yellow Sea Sediments and Its Indication for River-Delivered Radioactive Pollution to Marginal Seas.

As the number of coastal nuclear facilities rapidly increases and the wastewater from the Fukushima Nuclear Plant has been discharged into the Pacific Ocean, the nuclear environmental safety of China's marginal seas is gaining increased attention along with the heightened potential risk of nuclear accidents. However, insufficient work limits our understanding of the impact of human nuclear activities on the Yellow Sea (YS) and the assessment of their environmental process. This study first reports the 129I and 127I records of posthuman nuclear activities in the two YS sediments. Source identification of anthropogenic 129I reveals that, in addition to the gaseous 129I release and re-emission of oceanic 129I discharged from the European Nuclear Fuel Reprocessing Plants (NFRPs), the Chinese nuclear weapons testing fallout along with the global fallout is an additional 129I input for the continental shelf of the YS. The 129I/127I atomic ratios in the North YS (NYS) sediment are significantly higher than those in the other adjacent coastal areas, attributed to the significant riverine input of particulate 129I by the Yellow River. Furthermore, we found a remarkable 129I latitudinal disparity in the sediments than those in the seawaters in the various China seas, revealing that sediments in China's marginal seas already received a huge anthropogenic 129I from terrigenous sources via rivers and thus became a significant sink of anthropogenic 129I. This study broadens an insight into the potential impacts of terrigenous anthropogenic pollution on the Chinese coastal marine radioactive ecosystem.

Selection of reference genes in liproxstatin-1-treated K562 Leukemia cells via RT-qPCR and RNA sequencing.

BACKGROUND: Reverse transcription quantitative polymerase chain reaction (RT-qPCR) can accurately detect relative gene expression levels in biological samples. However, widely used reference genes exhibit unstable expression under certain conditions. METHODS AND RESULTS: Here, we compared the expression stability of eight reference genes (RPLP0, RPS18, RPL13, EEF1A1, ß-actin, GAPDH, HPRT1, and TUBB) commonly used in liproxstatin-1 (Lip-1)-treated K562 cells using RNA-sequencing and RT-qPCR. The expression of EEF1A1, ACTB, GAPDH, HPRT1, and TUBB was considerably lower in cells treated with 20 µM Lip-1 than in the control, and GAPDH also showed significant downregulation in the 10 µM Lip-1 group. Meanwhile, when we used geNorm, NormFinder, and BestKeeper to compare expression stability, we found that GAPDH and HPRT1 were the most unstable reference genes among all those tested. Stability analysis yielded very similar results when geNorm or BestKeeper was used but not when NormFinder was used. Specifically, geNorm and BestKeeper identified RPL13 and RPLP0 as the most stable genes under 20 µM Lip-1 treatment, whereas RPL13, EEF1A1, and TUBB were the most stable under 10 µM Lip-1 treatment. TUBB and EEF1A1 were the most stable genes in both treatment groups according to the results obtained using NormFinder. An assumed most stable gene was incorporated into each software to validate the accuracy. The results suggest that NormFinder is not an appropriate algorithm for this study. CONCLUSIONS: Stable reference genes were recognized using geNorm and BestKeeper but not NormFinder. Overall, RPL13 and RPLP0 were the most stable reference genes under 20 µM Lip-1 treatment, whereas RPL13, EEF1A1, and TUBB were the most stable genes under 10 µM Lip-1 treatment.

Rosmarinic acid in combination with ginsenoside Rg1 suppresses colon cancer metastasis via co-inhition of COX-2 and PD1/PD-L1 signaling axis.

Metastasis of colorectal cancer (CRC) is a leading cause of mortality among CRC patients. Elevated COX-2 and PD-L1 expression in colon cancer tissue has been linked to distant metastasis of tumor cells. Although COX-2 inhibitors and immune checkpoint inhibitors demonstrate improved anti-tumor efficacy, their toxicity and variable therapeutic effects in individual patients raise concerns. To address this challenge, it is vital to identify traditional Chinese medicine components that modulate COX-2 and PD-1/PD-L1: rosmarinic acid (RA) exerts striking inhibitory effect on COX-2, while ginsenoside Rg1 (GR) possesses the potential to suppress the binding of PD-1/PD-L1. In this study we investigated whether the combination of RA and GR could exert anti-metastatic effects against CRC. MC38 tumor xenograft mouse model with lung metastasis was established. The mice were administered RA (100 mg·kg-1·d-1, i.g.) alone or in combination with GR (100 mg·kg-1·d-1, i.p.). We showed that RA (50, 100, 150 µM) or a COX-2 inhibitor Celecoxib (1, 3, 9 µM) concentration-dependently inhibited the migration and invasion of MC38 cells in vitro. We further demonstrated that RA and Celecoxib inhibited the metastasis of MC38 tumors in vitro and in vivo via interfering with the COX-2-MYO10 signaling axis and inhibiting the generation of filopodia. In the MC38 tumor xenograft mice, RA administration significantly decreased the number of metastatic foci in the lungs detected by Micro CT scanning; RA in combination with GR that had inhibitory effect on the binding of PD-1 and PD-L1 further suppressed the lung metastasis of colon cancer. Compared to COX-2 inhibitors and immune checkpoint inhibitors, RA and GR displayed better safety profiles without disrupting the tissue structures of the liver, stomach and colon, offering insights into the lower toxic effects of clinical traditional Chinese medicine against tumors while retaining its efficacy.

Effector Protein Serine Carboxypeptidase FgSCP Is Essential for Full Virulence in F. graminearum and Is Involved in Modulating Plant Immune Responses.

Fusarium head blight (FHB) caused by Fusarium graminearum is a significant pathogen affecting wheat crops. During the infection process, effector proteins are secreted to modulate plant immunity and promote infection. The toxin deoxynivalenol (DON) is produced in infected wheat grains, posing a threat to human and animal health. Serine carboxypeptidases (SCPs) belong to the α/ß hydrolase family of proteases and are widely distributed in plant and fungal vacuoles as well as animal lysosomes. Research on SCPs mainly focuses on the isolation, purification of a small number of fungi as well as their study in plants.However, their functions in F. graminearum, a fungal pathogen, remain relatively unknown. In this study, the biological functions of the FgSCP gene in F. graminearum were investigated. The study revealed that mutations in FgSCP affected nutritional growth, sexual reproduction, and stress tolerance of F. graminearum. Furthermore, the deletion of FgSCP resulted in reduced pathogenicity and hindered the biosynthesis of DON. The upregulation of FgSCP expression three days after infection indicated its involvement in host invasion, possibly acting as a "smokescreen" to deceive the host and suppress the expression of host defensive genes. Subsequently, we confirmed the secretion ability of FgSCP and its ability to inhibit the cell death induced by INF1 in Nicotiana. benthamiana cells, indicating its potential role as an effector protein in suppressing plant immune responses and promoting infection. In summary, we have identified FgSCP as an essential effector protein in F. graminearum, playing critical roles in growth, virulence, secondary metabolism, and host invasion.

EphA2-specific microvesicles derived from tumor cells facilitate the targeted delivery of chemotherapeutic drugs for osteosarcoma therapy.

Despite advances in surgery and chemotherapy, the survival of patients with osteosarcoma (OS) has not been fundamentally improved over the last two decades. Microvesicles (MVs) have a high cargo-loading capacity and are emerging as a promising drug delivery nanoplatform. The aim of this study was to develop MVs as specifically designed vehicles to enable OS-specific targeting and efficient treatment of OS. Herein, we designed and constructed a nanoplatform (YSA-SPION-MV/MTX) consisting of methotrexate (MTX)-loaded MVs coated with surface-carboxyl Fe3O4 superparamagnetic nanoparticles (SPIONs) conjugated with ephrin alpha 2 (EphA2)-targeted peptides (YSAYPDSVPMMS, YSA). YSA-SPION-MV/MTX showed an effective targeting effect on OS cells, which was depended on the binding of the YSA peptide to EphA2. In the orthotopic OS mouse model, YSA-SPION-MV/MTX effectively delivered drugs to tumor sites with specific targeting, resulting in superior anti-tumor activity compared to MTX or MV/MTX. And YSA-SPION-MV/MTX also reduced the side effects of high-dose MTX. Taken together, this strategy opens up a new avenue for OS therapy. And we expect this MV-based therapy to serve as a promising platform for the next generation of precision cancer nanomedicines.

Phase retrieval from single-shot square wave fringe based on image denoising using deep learning.

Fringe-structured light measurement technology has garnered significant attention in recent years. To enhance measurement speed while maintaining a certain level of accuracy using binary fringe, this paper proposes a phase retrieval method with single-frame binary square wave fringe. The proposed method utilizes image denoising through deep learning to extract the phase, enabling the use of a trained image denoiser as a low-pass filter, which adaptively replaces the manual selection of the appropriate band-pass filter. The results demonstrate that this method achieves higher reconstruction accuracy than the traditional single-frame algorithm while preserving more object details.

A chromodomain protein mediates heterochromatin-directed piRNA expression.

PIWI-interacting RNAs (piRNAs) play significant roles in suppressing transposons, maintaining genome integrity, and defending against viral infections. How piRNA source loci are efficiently transcribed is poorly understood. Here, we show that in Caenorhabditis elegans, transcription of piRNA clusters depends on the chromatin microenvironment and a chromodomain-containing protein, UAD-2. piRNA clusters form distinct focus in germline nuclei. We conducted a forward genetic screening and identified UAD-2 that is required for piRNA focus formation. In the absence of histone 3 lysine 27 methylation or proper chromatin-remodeling status, UAD-2 is depleted from the piRNA focus. UAD-2 recruits the upstream sequence transcription complex (USTC), which binds the Ruby motif to piRNA promoters and promotes piRNA generation. Vice versa, the USTC complex is required for UAD-2 to associate with the piRNA focus. Thus, transcription of heterochromatic small RNA source loci relies on coordinated recruitment of both the readers of histone marks and the core transcriptional machinery to DNA.

Favorable Loci Identified for Stripe Rust Resistance in Chinese Winter Wheat Accessions via Genome-Wide Association Study.

Stripe rust (or yellow rust), caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating diseases of wheat worldwide. Currently, the utilization of resistant cultivars is the most viable way to reduce yield losses. In this study, a panel of 188 wheat accessions from China was evaluated for stripe rust resistance, and genome-wide association studies were performed using high-quality Diversity Arrays Technology markers. According to the phenotype and genotype data, a total of 26 significant marker-trait associations were identified, representing 18 quantitative trait loci (QTLs) on chromosomes 1B, 2A, 2B, 3A, 3B, 5A, 5B, 6B, 7B, and 7D. Of the 18 QTLs, almost all were associated with adult plant resistance (APR) except QYr.nwsuaf-6B.2, which was associated with all-stage resistance (also known as seedling resistance). Three of the 18 QTLs were mapped far from previously identified Pst resistance genes and QTLs and were considered potentially new loci. The other 15 QTLs were mapped close to known resistance genes and QTLs. Subsequent haplotype analysis for QYr.nwsuaf-2A and QYr.nwsuaf-7B.3 revealed the degrees of resistance of the panel in the APR stage. In summary, the favorable alleles identified in this study may be useful in breeding for disease resistance to stripe rust.

Detection of Biomolecules Using Solid-State Nanopores Fabricated by Controlled Dielectric Breakdown.

Nanopore sensor technology is widely used in biomolecular detection due to its advantages of low cost and easy operation. In a variety of nanopore manufacturing methods, controlled dielectric breakdown has the advantages of a simple manufacturing process and low cost under the premise of ensuring detection performance. In this paper, we have made enhancements to the applied pulses in controlled dielectric breakdown and utilized the improved dielectric breakdown technique to fabricate silicon nitride nanopores with diameters of 5 to 15 nm. Our improved fabrication method offers the advantage of precise control over the nanopore diameter (±0.4 nm) and enhances the symmetry of the nanopore. After fabrication, we performed electrical characterization on the nanopores, and the IV characteristics exhibited high linearity. Subsequently, we conducted detection experiments for DNA and protein using the prepared nanopores to assess the detection performance of the nanopores fabricated using our method. In addition, we also give a physical model of molecule translocation through the nanopores to give a reasonable explanation of the data processing results.

Negative Pressure in Water for Efficient Heat Utilization and Transfer.

Thermodynamic metastable water in negative pressure provides a possible solution to elevate the upper limit of evaporative heat transfer capacity and the efficiency of low-grade heat utilization, but practical implementations are challenging due to the difficulty in generating and maintaining large negative pressure. Herein, we report a novel structure with a hydrogel film as the evaporation surface and a permeable substrate as the functional layer to suppress cavitation. Based on the structure, we achieve an evaporation-driven flow system with negative pressure as low as -1.67 MPa. Molecular dynamics simulations elucidate the importance of strong water-polymer interactions in negative pressure generation. With the large negative pressure, we demonstrate a streaming potential generator that spontaneously converts environmental energy into electricity and outputs a voltage of 1.06 V. Moreover, we propose a "negative pressure heat pipe", which achieves a high heat transfer density of 9.6 kW cm-2 with a flow length of 1 m.

Realization of a Two-Dimensional Checkerboard Lattice in Monolayer Cu2N.

Two-dimensional checkerboard lattice, the simplest line-graph lattice, has been intensively studied as a toy model, while material design and synthesis remain elusive. Here, we report theoretical prediction and experimental realization of the checkerboard lattice in monolayer Cu2N. Experimentally, monolayer Cu2N can be realized in the well-known N/Cu(100) and N/Cu(111) systems that were previously mistakenly believed to be insulators. Combined angle-resolved photoemission spectroscopy measurements, first-principles calculations, and tight-binding analysis show that both systems host checkerboard-derived hole pockets near the Fermi level. In addition, monolayer Cu2N has outstanding stability in air and organic solvents, which is crucial for further device applications.