Search

Due to increasingly serious soil salinisation, exploring high‐quality closely related wild species is an effective means to solve food security problems. In this study, based on comprehensive metabolomics and transcriptomics analyses of the types, quantities, metabolic pathways and gene expression of small molecule metabolites in cotyledons and embryo axis/root, we report the strategies used by barren‐tolerant wild soybean (GS2) to resist salt stress during the post‐germination period. Our results showed that salt tolerance in GS2 cotyledons mainly involves the enhanced mobilisation of reserves, including lipid and sugar breakdown and utilisation, as well as protein breakdown and, in particular, the transport of amino acids to the embryo axis/root. Moreover, antioxidant capacity is enhanced through the promotion of ascorbic acid and naringin synthesis. We also found that under salt stress, the GS2 embryo axis/root accumulates proline by promoting the ornithine biosynthetic pathway, while stimulating glutathione metabolism to eliminate excess reactive oxygen species and restore oxidative balance. In addition, to establish and elongate the embryo axis/root, lignin synthesis is enhanced by the promotion of the shikimic acid pathway, which compensates for the decrease in cell wall support caused by salt stress. This study lays the foundation for developing and utilising high‐quality wild plant resources. [ABSTRACT FROM AUTHOR]

The ion–molecule reaction is one of the most important pathways for the formation of new interstellar chemical species. Herein, infrared spectra of cationic binary clusters of acrylonitrile (AN) with methanethiol (CH3SH) and dimethyl sulfide (CH3SCH3) are measured and compared to those previous studies of AN and methanol (CH3OH) or dimethyl ether (CH3OCH3). The results suggest that the ion–molecular reactions of AN with CH3SH and CH3SCH3 only yield products with S...HN H-bonded or S∴N hemibond structures, rather than the cyclic products as observed in AN-CH3OH and AN-CH3OCH3 studied previously. The Michael addition-cyclization reaction between acrylonitrile and sulfur-containing molecules does not occur due to the weaker acidity of CH bonds in sulfur-containing molecules, which results from their weaker hyperconjugation effect compared to oxygen-containing molecules. The reduced propensity for the proton transfer from the CH bonds hinders the formation of the Michael addition-cyclization product that follows. [ABSTRACT FROM AUTHOR]

The structure of the host lattice has a substantial influence on the optical properties of lanthanide-doped luminescent materials. Hexagonal-phase (β-phase) NaREF4 (RE = rare earth) is the most commonly used crystal structure for lanthanide-doped upconversion nanoparticles (UCNPs) owing to its high upconversion (UC) efficiency. In this work, we report, for the first time, that more efficient cooperative sensitization upconversion (CSU) can be achieved in cubic-phase (α-phase) NaREF4 UCNPs instead of their β-phase counterparts. With the passivation of an inert shell, the UC emission intensity of α-NaYbF4:Tb40%@CaF2 is 10.5 times higher than that of β-NaYbF4:Tb40%@NaYF4. We propose that the high-symmetry crystal structure of the α phase facilitates the formations of [Yb–Yb] dimers and [Yb–Yb–Tb] clusters, which are particularly beneficial for CSU. Moreover, we prove that such Tb3+-based UCNPs are almost impervious to water quenching because of the large energy gap (∼15,000 cm−1) that existed in Tb3+ between its lowest emit-ting level (5D4) and next low-lying level (7F0). Finally, their potential application for single-nanoparticle imaging has also been demonstrated. As expected, the α-core-shell UCNPs measured at the single-nanoparticle level are estimated to be 9-fold brighter than their β-core-shell counterparts. Importantly, the α-NaYbF4:Tb40%@CaF2 UCNPs offer exciting opportunities for realizing single-nanoparticle imaging at ultralow irradiance (30 W/cm2).

Atmospheric new particle formation (NPF), which exerts comprehensive implications for climate, air quality and human health, has received extensive attention. From molecule to cluster is the initial and most important stage of the nucleation process of atmospheric new particles. However, due to the complexity of the nucleation process and limitations of experimental characterization techniques, there is still a great uncertainty in understanding the nucleation mechanism at the molecular level. Laboratory‐based molecular beam methods can experimentally implement the generation and growth of typical atmospheric gas‐phase nucleation precursors to nanoscale clusters, characterize the key physical and chemical properties of clusters such as structure and composition, and obtain a series of their physicochemical parameters, including association rate coefficients, electron binding energy, pickup cross section and pickup probability and so on. These parameters can quantitatively illustrate the physicochemical properties of the cluster, and evaluate the effect of different gas phase nucleation precursors on the formation and growth of atmospheric new particles. We review the present literatures on atmospheric cluster formation and reaction employing the experimental method of laboratory molecular beam. The experimental apparatuses were classified and summarized from three aspects of cluster generation, growth and detection processes. Focus of this review is on the properties of nucleation clusters involving different precursor molecules of water, sulfuric acid, nitric acid and NxOy, respectively. We hope this review will provide a deep insight for effects of cluster physicochemical properties on nucleation, and reveal the formation and growth mechanism of atmospheric new particle at the molecular level. [ABSTRACT FROM AUTHOR]

The formation of nitrogen-containing organic interstellar molecules is of great importance to reveal chemical processes and the origin of life on Earth. Benzonitrile (BN) is one of the simplest nitrogen-containing aromatic molecules in the interstellar medium (ISM) that has been detected in recent years. Methanol (CH3OH) exists widely in interstellar space with high reactivity. Herein, we measured the infrared (IR) spectra of neutral and cationic BN–CH3OH clusters by vacuum ultraviolet (VUV) photoionization combined with time-of-flight mass spectrometry. Combining IR spectra with the density functional theory calculations, we reveal that the BN–CH3OH intends to form a cyclic H-bonded structure in neutral clusters. However, after the ionization of BN–CH3OH clusters, proton-shared N···H···O and N···H···C structures are confirmed to form between BN and CH3OH, with the minor coexistence of H-bond and O-π structures. The formation of the proton-shared structure expands our knowledge of the evolution of the life-related nitrogen-containing molecules in the universe and provides a possible pathway to the further study of biorelevant aromatic organic macromolecules. [ABSTRACT FROM AUTHOR]

This research is intended to evaluate the efficacy of percutaneous vertebroplasty (PVP) versus percutaneous kyphoplasty (PKP) in osteoporotic vertebral compression fracture (OVCF), which is associated with post‐operative pain. Eligible studies were screened by searching multiple databases and sources such as PubMed, Cochrane and EMBASE for search terms updated to October 2023, and relevant literature sources were searched. Randomized, controlled, prospective or retrospective, and cohort studies were eligible. For the analysis of the primary results, an analysis of the data was carried out, such as mean difference (MD) or odds ratio (OR), and 95% confidence interval (CI). In the present research, 1933 research was screened in 4 databases, and 30 articles were chosen to be examined under strict exclusion criteria. No statistical significance was found in the use of bone cement in the PVP group and PKP (MD, −0.60; 95% CI, −1.40, 0.21, p = 0.15); PKP was associated with a reduced risk of cement leak compared with PVP group (OR, 2.18; 95% CI, 1.38, 3.46, p = 0.0009); no statistical significance was found in the wound VAS score in PVP operation compared with that of PKP (MD, 0.16; 95% CI, −0.07, 0.40, p = 0.17); no statistical significance was found between the time of PVP operation and the time of PKP operation (MD, −2.65; 95% CI, −8.91, 3.60, p = 0.41). Compared with PVP technology, the PKP treatment of osteoporotic vertebral compression fractures reduces post‐operative cement leakage, but there is no significant difference in the number of operative cement and wound VAS after operation. Nor did there appear to be a statistically significant difference in time between the two operations. [ABSTRACT FROM AUTHOR]

Backgrounds: Previous studies have suggested that cerebral dural sinus stenosis could be a possible underlying cause of idiopathic intracranial hypertension (IIH). Venous sinus stenting (VSS) has emerged as a potential alternative for treating IIH related to dural sinus stenosis. However, most of the documented studies have been conducted in Western countries. In this study, we present the results of 16 Chinese IIH patients who underwent VSS treatment in our single center. Methods: We prospectively collected angiographic and manometric data from IIH patients who underwent angioplasty/stenting. All patients had confirmed dural sinus stenosis and had failed maximal medical therapy (MMT). Demographic, clinical, and radiological presentation, as well as long‐term follow‐up outcomes were collected retrospectively. Results: A total of 16 patients who underwent VSS were enrolled in the present study. Demographic data revealed a mean age of 40 (range 20–55), with 69% (11/16) being female, and a mean body mass index (BMI) of 27.05 (range 19.18–38.04) kg/m2. All patients presented with papilledema and visual disturbances. During a median follow‐up period of 47.5 months, 93.75% (15/16) of patients reported improvement in symptoms, although only 37.5% (6/16) experienced complete resolution. Headaches, blurred vision, and amaurosis related to increased pressure improved in 100% (8/8), 81.25% (13/16), and 75% (3/4) of patients, respectively. However, one patient suffered cerebral infarction and secondary epilepsy soon after VSS, and another patient had recurrence of symptoms due to stent wall thrombosis 2 years later. Conclusions: The significance of venous sinus stenosis in the development of IIH may be undervalued. Our study, based on a Chinese case series, affirms the long‐term safety and effectiveness of VSS in treating IIH patients with relatively lower BMI than those from Western countries. [ABSTRACT FROM AUTHOR]

Based on the climatic conditions in the northwest and the widely used water storage method in the northwest rural areas, we designed a rain and snow collection device, which is realized by an inductor and an “M” collection curtain, which uses the rotation of the motor and the supply of the heating film. Water purification and storage can be obtained through compound grit tanks, biochar adsorption systems, etc. The collected water resources can be integrated with water purification and storage through flood control and antifreeze devices. Real-time senses the changes of water level and water temperature. In this article, a calculation model for the optimal sedimentation effect is also established, which can calculate the minimum scale parameters of the sedimentation tank under different weather conditions, and provide guidance for the construction of the system. In addition, we tested the actual collection capacity of the system, and the results showed that the system has high practical value. At present, there is no a complete and systematic study integrated with it in the Northwest region. This system can alleviate the lack of water resources in some areas to a certain extent, play a positive role in the rural ecological environment and lessen flood

We developed a highly sensitive and stable SERS-active substrate of Au@Ag@Ag core/shell/shell nanorods, formed by encapsulating Au nanorods (Au NRs) into a bilayer silver shell with Raman reporter molecules (4-mercaptobenzoic acid (4-MBA) and thiram) in the shell–shell gap. The core/shell/shell nanostructures demonstrated a high SERS enhancement and easy assembly. The important role of the bilayer silver shell in boosting the SERS intensity and detection sensitivity was revealed by comparing the performances of the Au@Ag@4-MBA@Ag NRs, Au@Ag@4-MBA NRs, and Au@4-MBA NRs. The obtained Au@Ag@4-MBA@Ag NRs exhibited a significantly promoted SERS intensity, which could reach around 2.6 times and 240 times that of the Au@Ag@4-MBA NRs and Au@4-MBA NRs, where the enhancement factor was found to be strongly correlated with the shell thickness. The controllable plasma properties and SERS effect of the Au@Ag@4-MBA@Ag NRs could be optimized by adjusting the dose of silver nitrate. The SERS substrate comprising core/shell/shell nanorods was highly reproducible and stable (retaining 83% SERS intensity after one month). Moreover, the highly sensitive detection of the pesticide thiram with a detection limit as low as 1.74 × 10−9 M was achieved by taking advantage of the great SERS response of the core/shell/shell nanostructures, which was 1–2 orders of magnitude lower than for other SERS substrates. The developed SERS substrate could be readily extended to embed other target analytes into the core/shell/shell nanostructure for novel and sensitive detection. This study could enable fresh approaches toward next-generation ultrasensitive analyte detection. [ABSTRACT FROM AUTHOR]

The key to improve the service effect of virtual digital human is the personality trait recognition technology of users. However, the complexity of Chinese and the sparsity of short texts limit the accuracy of personality trait recognition. Therefore, we applied emotional features to the research of personality trait recognition and constructed a deep learning model for Chinese corpus personality trait recognition to improve the accuracy of personality trait recognition. The model ( R-B e) extracted semantic features and embedded emotional features through RoBERTa-wwm-ext Chinese pre-training model, BiLSTM neural network, and attention mechanism. Some experiments were carried out using two Chinese datasets with different scenes. The comparative experiments and ablation experiments showed that the overall effect of the personality trait recognition model ( R-B e) is the best, and the Macro-F1 value reaches 75.3%, which is significantly better than the existing models. The results showed that emotional features can significantly improve the accuracy of multi-label personality trait classification in both Chinese daily life scenarios and online scenarios. The proposed model can integrate emotional features and Chinese semantic features to improve the accuracy of personality traits recognition. These findings support the development of personality trait recognition and the application of virtual digital human. [ABSTRACT FROM AUTHOR]