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Compared with other transition metal Mxene derived quantum dots (MQDS), Ta-based Mxene quantum dots have good functionality, but Ta-based Mxene quantum dots and their applications have not been studied so far. In this paper, we report for the first time the synthesis of high fluorescence quantum yield (QY) N-doped Ta4C3 quantum dots (N-MQDs) using Ta4C3 quantum dots in acid reflux damaged Ta4C3 nanosheets as precursors and ethylenediamine as nitrogen source. The prepared N-MQDs have excellent blue photoluminescence (PL) properties, particle size is only 2.60 nm, QY is up to 23.4%, and good stability. In addition, it has been reported that N-MQDs can be used as fluorescent probe for detection of Fe3+ and remote force sensing analysis In liquid ion sensing, N-MQDS shows a unique selective quenching of Fe3+ with a detection limit as low as 2 μmol/L, and has great potential as a fast and super-sensitive fluorescent probe for the detection of heavy ion. More importantly, in solid mechanics sensing, the introduction of N-MQDs into self-healing hydrogels can be developed into a fluorescent hydrogel that can be used for accurate remote force measurement and applied in the field of mechanical sensing analysis. Therefore, Ta-based N-MQDs show excellent potential in the field of fluorescence sensing, which provides a door for multi-dimensional sensing of new materials in the future.

Flexible Al2O3/ZrO2 nanofibrous membranes of low density and high working temperature were fabricated by sol–gel electrospinning, and could be used for thermal-insulation applications.

In this paper, we report for the first time the preparation of full-color MXene quantum dots (MQDs) using V4C3. Importantly, the ML-driven XGB model guided our success in obtaining the optimal WLED with CIE color coordinates of (0.333, 0.397).

Light adaptation enables the vertebrate visual system to operate over a wide range of ambient illumination. Regulation of phototransduction in photoreceptors is considered a major mechanism underlying light adaptation. However, various types of neurons and glial cells exist in the retina, and whether and how all retinal cells interact to adapt to light/dark conditions at the cellular and molecular levels requires systematic investigation. Therefore, we utilized single-cell RNA sequencing to dissect retinal cell-type-specific transcriptomes during light/dark adaptation in mice. The results demonstrated that, in addition to photoreceptors, other retinal cell types also showed dynamic molecular changes and specifically enriched signaling pathways under light/dark adaptation. Importantly, Müller glial cells (MGs) were identified as hub cells for intercellular interactions, displaying complex cell‒cell communication with other retinal cells. Furthermore, light increased the transcription of the deiodinase Dio2 in MGs, which converted thyroxine (T4) to active triiodothyronine (T3). Subsequently, light increased T3 levels and regulated mitochondrial respiration in retinal cells in response to light conditions. As cones specifically express the thyroid hormone receptor Thrb, they responded to the increase in T3 by adjusting light responsiveness. Loss of the expression of Dio2 specifically in MGs decreased the light responsive ability of cones. These results suggest that retinal cells display global transcriptional changes under light/dark adaptation and that MGs coordinate intercellular communication during light/dark adaptation via thyroid hormone signaling.

Extrachromosomal circular DNA (eccDNA) is gaining substantial attention in basic and clinical research for its contribution to tumor heterogeneity, biogenesis, and evolution. However, its presence and molecular features in peripheral blood from cancer patients are poorly understood. Here, we demonstrated the existence of eccDNA molecules in cancer patients’ plasma using atomic-force microscopy and high throughput sequencing technology. We then developed a method named ScanTecc (Screening cancer Types with cell-free eccDNA) that integrates cell-free circular DNA sequencing and machine learning approaches for cancer patient screening and classification. We applied ScanTecc on a total of 413 patients with multiple types of human primary cancers and 52 healthy individuals and found a significantly greater number and more extended size of eccDNAs in patients’ peripheral blood. ScanTecc accurately distinguished cancer patients (including early stages I and II) from healthy individuals with an overall prediction rate of 0.85 and identified distinct cancer types with an overall prediction rate of 0.84. Our study provides evidence for a non-invasive approach potentially applicable for early detection of cancer patients in clinics.

Retinitis pigmentosa (RP) is a form of inherited retinal degenerative diseases that ultimately involves the macula, which is present in primates but not in the rodents. Therefore, creating nonhuman primate (NHP) models of RP is of critical importance to study its mechanism of pathogenesis and to evaluate potential therapeutic options in the future. Here we applied adeno-associated virus (AAV)-delivered CRISPR/SaCas9 technology to knockout the RHO gene in the retinae of the adult rhesus macaque (Macaca mulatta) to investigate the hypothesis whether non-germline mutation of the RHO gene is sufficient to recapitulate RP. Through a series of studies, we were able to demonstrate successful somatic editing of the RHO gene and reduced RHO protein expression. More importantly, the mutant macaque retinae displayed clinical RP phenotypes, including photoreceptor degeneration, retinal thinning, abnormal rod subcellular structures, and reduced photoresponse. Therefore, we suggest somatic editing of the RHO gene is able to phenocopy RP, and the reduced time span in generating NHP mutant accelerates RP research and expands the utility of NHP model for human disease study.

L-Threonine, a methylamino acid with side chains forming hydrogen bonds and nonpolar interactions, is an important amino acid in cosmetics, foods, and veterinary drugs. However, up to now, there are few studies on the fluorescence detection of L-threonine. In this work, a fluorescent sensing platform with yellow emission fluorescent carbon dots (CDs) as signal transmission probes is synthesized by a simple, convenient and environmentally friendly one-pot hydrothermal method, and a fluorescence resonance energy transfer donor/acceptor pair is constructed to detect the L-threonine content in the sample with high selectivity and sensitivity in the range of 0.1–0.5 mM, and the detection limit is 6.15 μM. In addition, CDs exhibit good photostability and photoluminescence properties under different salt solutions, pH values and time conditions, and are successfully used for the detection of L-threonine in real samples.

Water pollution caused by oil spillages has aroused worldwide attention. Therefore, it is of great significance to develop low-cost, environmentally friendly materials to remove oil contaminants from water. Herein, a “green” superhydrophobic sponge made from marine algae was fabricated by one-step growth of silicone nanofilaments onto a AgNP-decorated alginate sponge via chemical vapor deposition of an azeotrope of (CH3)3SiCl and SiCl4. The reaction of the azeotrope with the alginate sponge was termed “instant”, as it took only a few minutes (5 min) at room temperature to achieve superhydrophobicity (152.0°). Such sponges resist high temperatures, UV irradiation, organic solvents, and mechanical abrasion without losing the superhydrophobicity. The sponges absorbed oil droplets within seconds (1.3–7.0 s) with 11.7–17.1 g/g of sorption capacities for oils of different viscous levels (0.56–1775.00 mPa·s). These sponges could retain 90% of the initial oil sorption capacities after 10 consecutive oil sorption/desorption cycles. Benefiting from the superhydrophobicity and superoleophilicity, the sponges also exhibited high efficiency in oil/water mixture separation. Once the oil/water mixture was injected into the sponge, oil drops were retained in inner pores while water was rejected and spouted from the surface. These excellent performances make the resultant sponge a competitive material for oil spill emergency remediation.

Methyltransferase like 9 (Mettl9) is a member of the methyltransferase like protein family which is characterized by the presence of binding domains for S-adenosyl methionine, (SAM), a co-substrate for methylation reactions. Despite METTL9 is predicted to be a methyltransferase, its enzymatic activity, substrate specificities and biological functions are still poorly characterized. In this study, we revealed a tumor-promoting role for METTL9. We found that deletion of Mettl9 in tumor cells suppresses tumor growth and elicits potent anti-tumor immunity. Mechanistically, METTL9 is a N1-histidine methyltransferase which methylates the histidine residues of a x-His-x-His (xHxH) motif on the substrates. This motif is found extensively in zinc transporter families SLC39s and SLC30s, particularly in SLC39A7. Deletion of Mettl9 impairs cytoplasmic zinc homeostasis, resulting in an altered gene expression program with increased endoplasmic reticulum (ER) stress and reduced cell cycle. Mutation of key METTL9 catalyzed methylhistidine residues of SLC39A7 impairs cytoplasmic zinc homeostasis and affects cell growth as well. Notably, METTL9 expression is increased in some cancer types and its higher expression is associated with worse clinical outcomes, particularly in liver and pancreatic cancer. In summary, our work identified METTL9 as a potential new oncogene and its mediated methylation is of regulatory importance. Identifying selective and potent small-molecule inhibitors of METTL9 could thus represent novel therapeutic strategy for anti-proliferative cancer drugs.

The human retina is a complex neural tissue that detects light and sends visual information to the brain. However, the molecular and cellular processes that underlie aging primate retina remain unclear. Here, we provide a comprehensive transcriptomic atlas based on 119,520 single cells of the foveal and peripheral retina of humans and macaques covering different ages. The molecular features of retinal cells differed between the two species, suggesting the distinct regional and species specializations of the human and macaque retinae. In addition, human retinal aging occurred in a region- and cell-type- specific manner. Aging of human retina exhibited a foveal to peripheral gradient. MYO9A− rods and a horizontal cell subtype were greatly reduced in aging retina, indicating their vulnerability to aging. Moreover, we generated a dataset showing the cell-type- and region- specific gene expression associated with 55 types of human retinal disease, which provides a foundation to understand the molecular and cellular mechanisms underlying human retinal diseases. Together, these datasets are valuable for understanding the molecular characteristics of primate retina, as well as the molecular regulation of aging progression and related diseases.

Retinitis pigmentosa (RP) is a form of inherited retinal degenerative disease that ultimately involves the macula, which is present in primates but not in the rodents. Therefore, creating nonhuman primate (NHP) models of RP is of critical importance to study its mechanism of pathogenesis and to evaluate potential therapeutic options in the future. Here we applied adeno-associated virus (AAV)-delivered CRISPR/SaCas9 technology to knockout the RHO gene in the retinae of the adult rhesus macaque (Macaca mulatta) to investigate the hypothesis whether non-germline mutation of the RHO gene is sufficient to recapitulate RP. Through a series of studies, we were able to demonstrate successful somatic editing of the RHO gene and reduced RHO protein expression. More importantly, the mutant macaque retinae displayed clinical RP phenotypes, including photoreceptor degeneration, retinal thinning, abnormal rod subcellular structures, and reduced photoresponse. Therefore, we suggest somatic editing of the RHO gene is able to phenocopy RP, and the reduced time span in generating NHP mutant accelerates RP research and expands the utility of NHP model for human disease study.

The human retina is a complex neural tissue that detects light and sends visual information to the brain. However, the molecular and cellular processes that underlie aging primate retina remain unclear. Here, we provide a comprehensive transcriptomic atlas based on 119,520 single cells of the foveal and peripheral retina of humans and macaques covering different ages. The molecular features of retinal cells differed between the two species, suggesting the distinct regional and species specializations of the human and macaque retinae. In addition, human retinal aging occurred in a region- and cell-type- specific manner. Aging of human retina exhibited a foveal to peripheral gradient. MYO9A− rods and a horizontal cell subtype were greatly reduced in aging retina, indicating their vulnerability to aging. Moreover, we generated a dataset showing the cell-type- and region- specific gene expression associated with 55 types of human retinal disease, which provides a foundation to understand the molecular and cellular mechanisms underlying human retinal diseases. Together, these datasets are valuable for understanding the molecular characteristics of primate retina, as well as the molecular regulation of aging progression and related diseases.

Proppants play an important role to increase oil and gas output in shale oil and gas development process. Tracers are used to study the degree of heterogeneity and dynamic equivalence between injection and production wells to judge the state of oil reservoir. However, it is difficult to integrate both slow-release tracing and shale supporting functions in one material. The development of functional coated proppants with tracer slow-release function is of great significance. Here a simple method is developed to introduce a carbon quantum dots (CQDs) into polyvinyl alcohol (PVA) coated proppants and fabricate novel self-suspension proppants with tracer slow-release function. The PVA coating layer on ceramic proppants achieves the self-suspension ability. In the well, the PVA film melted in fracturing fluid and the CQDs were released as a tracer for downhole monitoring. The surface adhesion force of PVA-CQDs coated proppants is 2 times larger than that of ordinary ceramic proppants, and the liquid conductivity of the self-suspension slow-release tracer proppants (SSTP) can reach 51 D cm, which is 22.45% higher than original ceramic proppants at the closure pressure of 40 MPa. This work combined the coated proppants with the quantum dot tracer and obtained a new type of coated proppants with tracer slow-release function, which has a promising significance to improve oil and gas production and conducting cross-well monitoring.

Organophosphorus-based chemical warfare agents (CWAs) are highly poisonous, and recent attacks using nerve agents have stimulated researchers to develop breakthrough materials for their fast degradation. Zr-based materials have been identified as the most effective catalysts for breaking down CWAs, but in their powdered form, their practical application in personal protective equipment is limited. Herein, a surface-confined strategy for the direct growth of vertically aligned zirconium hydroxide (Zr(OH)4 ) nanosheets with ultrathin and tortuous structures on nanofibers is reported. The freestanding Zr(OH)4 nanosheet-assembled nanofibrous membranes (NANMs) show superior catalytic performance to degrade dimethyl methylphosphonate, a nerve agent simulant, with a half-life of 4 min. In addition, intriguing membrane-type NANMs feature integrated properties of exceptional breathability, prominent flexibility, and robust fatigue resistance over one million buckling loads. This facile strategy provides a novel route to manufacture new classes of nanosheet-supported membranes for chemical-protective materials, in particular for gas filters, protective suits, and clothing.