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Although organic–inorganic hybrid materials have played indispensable roles as mechanical 1 – 4 , optical 5 , 6 , electronic 7 , 8 and biomedical materials 9 – 11 , isolated organic–inorganic hybrid molecules (at present limited to covalent compounds 12 , 13 ) are seldom used to prepare hybrid materials, owing to the distinct behaviours of organic covalent bonds 14 and inorganic ionic bonds 15 in molecular construction. Here we integrate typical covalent and ionic bonds within one molecule to create an organic–inorganic hybrid molecule, which can be used for bottom-up syntheses of hybrid materials. A combination of the organic covalent thioctic acid (TA) and the inorganic ionic calcium carbonate oligomer (CCO) through an acid–base reaction provides a TA–CCO hybrid molecule with the representative molecular formula TA 2 Ca(CaCO 3 ) 2 . Its dual reactivity involving copolymerization of the organic TA segment and inorganic CCO segment generates the respective covalent and ionic networks. The two networks are interconnected through TA–CCO complexes to form a covalent–ionic bicontinuous structure within the resulting hybrid material, poly(TA–CCO), which unifies paradoxical mechanical properties. The reversible binding of Ca 2+ –CO 3 2− bonds in the ionic network and S–S bonds in the covalent network ensures material reprocessability with plastic-like mouldability while preserving thermal stability. The coexistence of ceramic-like, rubber-like and plastic-like behaviours within poly(TA–CCO) goes beyond current classifications of materials to generate an ‘elastic ceramic plastic’. The bottom-up creation of organic–inorganic hybrid molecules provides a feasible pathway for the molecular engineering of hybrid materials, thereby supplementing the classical methodology used for the manufacture of organic–inorganic hybrid materials. Covalent organic molecules can be combined with ionic inorganic molecules to create a hybrid material demonstrating paradoxical mechanical properties in a bottom-up manner, enabling the manufacture of an ‘elastic ceramic plastic’.

Quantification of nanoparticle-molecule interaction at a single-molecule level remains a daunting challenge, mainly due to ultra-weak emission from single molecules and the perturbation of the local environment. Here we report the rational design of an intraparticle-surface energy transfer (i-SET) process, analogous to high doping concentration-induced surface quenching effects, to realize single-molecule sensing by nanoparticle probes. This design, based on a Tb 3+ -activator-rich core-shell upconversion nanoparticle, enables a much-improved spectral response to fluorescent molecules at single-molecule levels through enhanced non-radiative energy transfer with a rate over an order of magnitude faster than conventional counterparts. We demonstrate a quantitative analysis of spectral changes of one to four fluorophores tethered on a single nanoparticle through i-SET spectroscopy. Our results provide opportunities to identify photoreaction kinetics at single-molecule levels and provide direct information for understanding behaviors of individual molecules with unprecedented sensitivity. Single-molecule sensing is very challenging due to weak emitted signals and environmental interference. Here the authors design a method (i-SET) for single molecule sensing with core-shell upconverting nanoparticles, which relies on signal enhancement by the activator-rich probes to quantify fluorophores attached to a single nanoparticle.

Color centers in diamond are promising solid-state qubits for scalable quantum photonics applications. Amongst many defects, those with inversion symmetry are of an interest due to their promising optical properties. In this work, we demonstrate a maskless implantation of an array of bright, single germanium vacancy (GeV) centers in diamond. Employing the direct focused ion beam technique, single GeV emitters are engineered with the spatial accuracy of tens of nanometers. The single GeV creation ratio reaches as high as 53% with the dose of 200 Ge+ ions per spot. The presented fabrication method is promising for future nanofabrication of integrated photonic structures with GeV emitters as a leading platform for spin-spin interactions.

A bifunctional Ni-MOF nanosheet was synthesized and developed for label-free fluorescent detection of H 2 O 2 and glucose. The Ni-MOF exhibited intrinsic peroxidase-like activity and its catalytic activity was demonstrated to be originated from the hydroxyl radicals (•OH) produced in catalytic process. Since the generated •OH enabled terephthalic acid, the non-fluorescent organic ligand of Ni-MOF, to form a strongly fluorescent 2-hydroxy terephthalic acid, the Ni-MOF nanozyme was endowed with dual-function properties of mimicking peroxidase and emitting fluorescence. Based on this bifunctional Ni-MOF nanozyme, the proposed label-free fluorescence sensing strategy was applied to detecting H 2 O 2 and glucose with wide linear ranges of 0.1–20 mM and 8–30 μM, and low detection limits of 4.0 × 10 −5  M and 4.0 × 10 −6  M, respectively. Furthermore, the bifunctional Ni-MOF-based label-free sensing platform was successfully used for the glucose detection in human serum samples, showing good reproducibility and high accuracy. This strategy provides a green and sensitive method for the determination of small biomolecules in practical applications by the combination of enzyme cascade reaction. Graphical abstract

Osteoporosis is an incurable chronic disease characterized by a lack of mineral mass in the bones. Here, the full recovery of osteoporotic bone is achieved by using a calcium phosphate polymer‐induced liquid‐precursor (CaP‐PILP). This free‐flowing CaP‐PILP material displays excellent bone inductivity and is able to readily penetrate into collagen fibrils and form intrafibrillar hydroxyapatite crystals oriented along the c‐axis. This ability is attributed to the microstructure of the material, which consists of homogeneously distributed ultrasmall (≈1 nm) amorphous calcium phosphate clusters. In vitro study shows the strong affinity of CaP‐PILP to osteoporotic bone, which can be uniformly distributed throughout the bone tissue to significantly increase the bone density. In vivo experiments show that the repaired bones exhibit satisfactory mechanical performance comparable with normal ones, following a promising treatment of osteoporosis by using CaP‐PILP. The discovery provides insight into the structure and property of biological nanocluster materials and their potential for hard tissue repair. The fluidity of calcium phosphate polymer‐induced liquid‐precursor (CaP‐PILP) allows the minimally‐invasive injection recovery of osteoporotic bone without the need for surgical incision in clinical applications. CaP‐PILP can recover osteoporotic bone back to normal, with a mechanical performance comparable to that of healthy bone. The unique characteristics of the material enable its application in osteoporotic bone recovery.

Esophageal stricture is a common complication after endoscopic submucosal dissection (ESD) for superficial esophageal cancer and precancerous lesions, we intend to investigate the independent risk factors of esophageal stricture after ESD by adding the data of included living habits, established a nomogram model to predict the risk of esophageal stricture, and verified it by external data. The clinical data and living habits of patients with early esophageal cancer and precancerous lesions who underwent ESD in the Affiliated Hospital of North Sichuan Medical College and Langzhong People's Hospital from March 2017 to August 2021 were retrospectively collected. The data collected from the two hospitals were used as the development group ( n  = 256) and the validation group ( n  = 105), respectively. Univariate and multivariate logistic regression analyses were used to determine independent risk factors for esophageal stricture after ESD and establish a nomogram model for the development group. The prediction performance of the nomogram model is internally and externally verified by calculating C-Index and plotting the receiver operating characteristic curve (ROC) and calibration curve, respectively. The results showed that Age, drinking water temperature, neutrophil–lymphocyte ratio, the extent of esophageal mucosal defect, longitudinal diameter of resected mucosa, and depth of tissue invasion ( P  < 0.05) were independent risk factors for esophageal stricture after ESD. The C-Index of the development group and validation group was 0.925 and 0.861, respectively. The ROC curve and area under the curve (AUC) of the two groups suggested that the discrimination and prediction performance of the model were good. The two groups of calibration curves are consistent and almost overlap with the ideal calibration curve, indicating that the predicted results of this model are in good agreement with the actual observed results. In conclusion, this nomogram model has a high accuracy for predicting the risk of esophageal stricture after ESD, providing a theoretical basis for reducing or avoiding esophageal stricture and guiding clinical practice.

Pasteurized yogurt is a healthy yogurt that can be stored in ambient temperature conditions. Dynamic headspace sampling (DHS) combined with gas chromatography-olfactory mass spectrometry (GC-O-MS), sensory evaluation, electronic nose (E-nose), and partial least squares discriminant analysis (PLS-DA) were used to analyze the flavor changes of pasteurized yogurt with different process combinations before and after aging. The results of odor profiles showed that the sensory descriptors of fermented, sweet, and sour were greatly affected by different process combinations. The results of odor-active compounds and relative odor activity value (r-OAV) showed that the combination of the production process affected the overall odor profile of pasteurized yogurt, which was consistent with the sensory evaluation results. A total of 15 odor-active compounds of 38 volatile compounds were detected in pasteurized yogurt samples. r-OAV results revealed that hexanal, (E)-2-octenal, 2-heptanone, and butanoic acid may be important odor-active compounds responsible for off-odor in aged, pasteurized yogurt samples. PLS-DA and variable importance of projection (VIP) results showed that butanoic acid, hexanal, acetoin, decanoic acid, 1-pentanol, 1-nonanal, and hexanoic acid were differential compounds that distinguish pasteurized yogurt before and after aging.

Presently, in the context of the novel coronavirus pneumonia epidemic, several antibiotics are overused in hospitals, causing heavy pressure on the hospital’s wastewater treatment process. Therefore, developing stable, safe, and efficient hospital wastewater treatment equipment is crucial. Herein, a bench-scale electrooxidation equipment for hospital wastewater was used to evaluate the removal effect of the main antibiotic levofloxacin (LVX) in hospital wastewater using response surface methodology (RSM). During the degradation process, the influence of the following five factors on total organic carbon (TOC) removal was discussed and the best reaction condition was obtained: current density, initial pH, flow rate, chloride ion concentration, and reaction time of 39.6 A/m2, 6.5, 50 mL/min, 4‰, and 120 min, respectively. The TOC removal could reach 41% after a reaction time of 120 min, which was consistent with the result predicted by the response surface (40.48%). Moreover, the morphology and properties of the electrode were analyzed. The degradation pathway of LVX was analyzed using high-performance liquid chromatography–mass spectrometry (LC–MS). Subsequently, the bench-scale electrooxidation equipment was changed into onboard-scale electrooxidation equipment, and the onboard-scale equipment was promoted to several hospitals in Dalian.

Background hyperlipidemia acute pancreatitis (HTG-AP) is a major hidden danger affecting human health, however, whether there is a protective effect of resveratrol on HTG-AP is unclear. Therefore our study was aimed to investigate the preventive effect and the underlying mechanism of resveratrol in the HTG-AP mice model. Methods This research was divided into two parts. In the first part, mice were adaptively fed with normal chow or HFD for 6 weeks. From the second week, resveratrol-treated mice were in intragastric administration with resveratrol (45 mg/kg/d) for 4 weeks. In the second part, the procedures were the same as the first part. After the last intragastric administration with resveratrol, all mice were intraperitoneal injections of cerulean. Results We found resveratrol effectively inhibited pancreatic pathological injury in the HFD, AP, and HTG-AP mice. Resveratrol reduced the LPS, IL-6, TNF-α, and MCP-1 expressions in the HFD mice. Resveratrol also reduced TNF-α, MDA, and MCP-1 expressions and increased SOD and T-AOC expressions in the AP and HTG-AP mice. Furthermore, resveratrol suppressed the NF-κB pro-inflammatory signaling pathway in pancreatic tissues in the AP and HTG-AP mice. Moreover, resveratrol improved the gut microbiota in the HFD mice. Conclusion The resveratrol pre-treatment could attenuate pancreas injury, inflammation, and oxidative stress in the HTG-AP mice, via restraining the NF-κB signaling pathway and regulating gut microbiota. Therefore, Our study proved that the resveratrol pre-treatment had a preventive effect on HTG-AP.

Localized interlayer excitons (LIXs) in two-dimensional moiré superlattices exhibit sharp and dense emission peaks, making them promising as highly tunable single-photon sources. However, the fundamental nature of these LIXs is still elusive. Here, we show the donor-acceptor pair (DAP) mechanism as one of the origins of these excitonic peaks. Numerical simulation results of the DAP model agree with the experimental photoluminescence spectra of LIX in the moiré MoSe 2 /WSe 2 heterobilayer. In particular, we find that the emission energy-lifetime correlation and the nonmonotonic power dependence of the lifetime agree well with the DAP IX model. Our results provide insight into the physical mechanism of LIX formation in moiré heterostructures and pave new directions for engineering interlayer exciton properties in moiré superlattices. The nature of localized interlayer excitons (LIXs) in moiré superlattices is still elusive Here, the authors propose a donor-acceptor pair mechanism for LIXs in MoSe 2 /WSe 2 heterobilayers.