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Neptunium is one of long-life radioelements, whose speciation in different condition of underground water and soil type, including the adsorption characteristics and adsorption mechanism on some soils, is a critical field. The adsorption behavior of Np(Ⅴ) on muscovite minerals was studied by combining theoretical calculations and static adsorption experiments, providing a reference for evaluating the safety of nuclear waste disposal sites in this work. The adsorption behavior of 239Np(Ⅴ) by different particle sizes of muscovite was studied using characterization methods such as X-ray diffraction(XRD), scanning electron microscopy(SEM), material specific surface area(BET), and NaI(Tl) gamma spectroscopy. Explored the effects of factors such as time, pH value, and the presence or absence of \begin{document}${\mathrm{CO}}_3^{2-} $\end{document} on the adsorption of Np(Ⅴ) by muscovite with different particle sizes. Combining density functional based on first principles, B3LYP was selected as the functional and 6-31G* as the basis group, and quantum chemical calculations were carried out to obtain the dissociation constant(pKa) values of the sites, in order to describe the electronic behavior of the skeleton structure. The experimental results show that different particle sizes of muscovite have an impact on the adsorption of Np(Ⅴ), and the presence or absence of \begin{document}${\mathrm{CO}}_3^{2-} $\end{document} in the environment also affect the adsorption distribution coefficient. However, as the particle size of muscovite decreases, more active sites are exposed, and the trend of adsorption distribution coefficient varies. Based on the SEM image and adsorption distribution coefficient curve, it can be seen that as the grinding mesh size of the sample increases, the end face increases, and even layered muscovite is peeled off. In the alkaline region, the adsorption distribution coefficient slightly increases, but the adsorption distribution coefficient is all less than 100. A small amount of Np(Ⅴ) is enriched in fine-grained to extremely fine-grained minerals, related to finer sediment. The adsorption of Np(Ⅴ) by muscovite is weak and not dominant. Np(Ⅴ) mainly migrates with groundwater in muscovite minerals.

Abstract. Introduction:. Chronic pain is a common and problematic consequence of injuries with few proven methods for prevention or treatment. In addition to pain, functional limitations and neuropsychiatric changes such as cognitive impairment and anxiety worsen outcomes. Objectives:. To determine whether inhibiting activation of the adaptive immune response after limb fracture would reduce pain, functional loss, memory changes, and anxiety. Methods:. These experiments used a murine tibial fracture/cast immobilization model that develops these adverse outcomes. Adaptive immunity was blocked using the immunosuppressant FK506 beginning at the time of fracture. Results:. The administration of FK506 reduced mechanical allodynia and hind limb unweighting for weeks after cast removal as well as nonevoked pain measures. Fracture was associated with working memory loss in the Y-maze assay in vehicle- but not FK506-treated mice. Object recognition memory was not improved with FK506 after fracture. Also, vehicle- but not FK506-treated mice developed an anxiety phenotype. Impaired running wheel performance after cast removal over the following 2 weeks was not improved with FK506 administration. In addition, FK506 treatment blocked Immunoglobulin M (IgM) accumulation in the skin of the fractured limbs, and hippocampal enhancement of matrix metalloproteinase-8 expression, a metalloproteinase associated with neuroplastic changes after injuries, was completely blocked. Conclusion:. Taken together, our results show that blocking the adaptive immune response after limb trauma reduces the severity of nociceptive and biological changes. The same treatment may reduce the adverse consequences of anxiety and memory deficits using some measures, but other measures of memory are not affected, and activity is not enhanced.

It is critical to develop the methods and technologies of studying the species and concentration in the processing of adsorption, and diffusion of some important radionuclides in spent fuel waste processing such as Beishan granites in domestic institutions and universities for the geological disposal of high-level radioactive wastes. Enrich the models used or constructed and the calculation procedures developed in the past two decades in this field. In order to evaluate the safety of the repository, chemical speciation analysis of nuclides is the premise of research to accurately predict the migration behavior of nuclides. In view of the rapid development of China's nuclear energy industry and the need to establish the identification of nuclides in the environment, it is of great significance to carry out the study of the chemical forms of nuclides around the repository in China. Aiming at the research requirements of element speciation distribution in the environment, a set of B/S architecture element speciation distribution simulation software is developed with JAVA as the development tool, MySQL as the database, and Tomcat as the container. In order to solve the convergence problem of chemical reaction equilibrium nonlinear equations encountered in simulation calculation, the method based on chemical reaction potential energy is introduced to solve the chemical reaction nonlinear equations quickly, and the multi-phase equilibrium calculation can be expanded. SSCS was used to study the species of U in groundwater and the effects of Eh, pH, different ions and concentrations. The calculation results indicate that neptunium mainly exists as NpO2CO-3(aq) in groundwater. Under strong acidic conditions, neptunium maily exists as NpO+2(aq), while in weak acidic, neutral or weak alkaline conditions, the main species are NpO+2(aq) and NpO2OH.When the solution is in strong alkaline conditions, the species are complicated most of neptunium exists as NpO2(CO3)-3(aq), with the possible generation of NpO2(CO3)3-2 or NpO2(CO3)5-3. Np(Ⅴ) is stable in the reduction condition, while Np(Ⅳ) and Np(Ⅵ) are the possible generation. Comparing the neptunium calculation results of the software in the environment with the PHREEQC calculation results, the relative error is within 10 %. For the distribution of trace elements in the environment, a theoretical calculation solution is provided.

Microinjection molding (μIM) is an important technique to fabricate microparts for applications in the fields of automotive and microelectromechanical systems. However, the prevailing high shear conditions in μIM are unfavorable for constructing intact electrically conductive networks because the added fillers tend to be preferentially aligned along the melt flow direction. In this work, a series of polypropylene/polyamide 6/carbon black (PP/PA6/CB) composites with a selective localization of CB in the PA6 phase were used as the model system to prepare electrically conductive microparts. The prevailing high shearing and extensional flow effects in μIM were utilized to deform CB-rich phase with an aim to in situ construct electrically conductive network, thereby improving the electrical conductivity (σ) of subsequent moldings. The results indicated that a higher σ was achieved for PP/PA6/CB microparts when compared with their PP/CB and PA6/CB counterparts, at a lower filler content (

Abstract Fruit color influences fruit quality and commodity value. Most longan (Dimocarpus longan Lour.) varieties have a yellowish-brown or grayish-yellow pericarp, and the discovery of red pericarp (RP) longan expanded the color varieties of longan fruit. Our previous research showed that the red pericarp of RP fruit was mainly caused by anthocyanin accumulation; however, its underlying regulatory mechanism remains unknown. Herein, DlMYB113, an R2R3-MYB transcription factor, was discovered by examining differentially expressed genes in two longan cultivars. Dimocarpus longan MYB (v-myb avian myeloblastosis viral) 113 (DlMYB113) expression was significantly higher in the pericarp and leaves of RP longan than in ‘Shixia’ longan. Sequence alignment analysis revealed two amino acid substitutions in the R3 domain between DlMYB113rp in RP longan and DlMYB113sx in ‘Shixia’ longan. Transient expression of DlMYB113rp significantly increased anthocyanin accumulation in tobacco leaves, whereas DlMYB113sx had negligible effect. Meanwhile, DlMYB113 overexpression promotes anthocyanin accumulation in Arabidopsis and longan calli. Site-directed mutation detection revealed divergence in DlMYB113 function when the R3 repeat 197-position base T was replaced with G, and the 317- and 318-position AT bases were replaced with GA. Our findings indicate that DlMYB113 can regulate anthocyanin production in RP longan, and three mutations in its nucleic acid sequence lead to anthocyanin accumulation, thereby developing molecular markers associated with the anthocyanin accumulation trait in RP longan. This study will facilitate early screening of longan hybrids with desirable fruit color and be significant for breeding new characteristic varieties.

Abstract The application of DNA barcoding has been significantly limited by the scarcity of reliable specimens and inadequate coverage and replication across all species. The deficiency of DNA barcode reference coverage is particularly striking for highly biodiverse subtropical and tropical regions. In this study, we present a comprehensive barcode library for woody plants in tropical and subtropical China. Our dataset includes a standard barcode library comprising the four most widely used barcodes (rbcL, matK, ITS, and ITS2) for 2,520 species from 4,654 samples across 49 orders, 144 families, and 693 genera, along with 79 samples identified at the genus level. This dataset also provides a super-barcode library consisting of 1,239 samples from 1,139 species, 411 genera, 113 families, and 40 orders. This newly developed library will serve as a valuable resource for DNA barcoding research in tropical and subtropical China and bordering countries, enable more accurate species identification, and contribute to the conservation and management of tropical and subtropical forests.

Graphene oxide(GO) has attracted extensive attention in the field of water environment treatment due to its large specific surface area and rich oxygen-containing functional groups. Graphene oxide was modified by carboxylation. The effects of solution pH, ionic strength, reaction time and initial concentration on the adsorption performance of carboxylated graphene oxide were systematically studied. It was found that carboxylated graphene oxide has strong adsorption capacity for Nd3+. The adsorption rate of Nd3+ on carboxylated graphene oxide is very fast, and most of Nd3+ can be adsorbed in 10 min. The adsorption equilibrium can be reached in 30 min, which is accord with the pseudo-second-order kinetic model. The adsorption performance is almost not affected by ionic strength. The adsorption isotherm is in accordance with Langmuir model, which indicates that the adsorption process is monolayer chemical adsorption. The study of Nd3+ adsorption behavior by carboxylated GO materials provides a new choice for the separation of rare earth elements in water treatment.

Acquired brain injury (ABI) is the most common disease of the nervous system, involving complex pathological processes, which often leads to a series of nervous system disorders. The structural destruction and dysfunction of the Neurovascular Unit (NVU) are prominent features of ABI. Therefore, understanding the molecular mechanism underlying NVU destruction and its reconstruction is the key to the treatment of ABI. SUMOylation is a protein post-translational modification (PTM), which can degrade and stabilize the substrate dynamically, thus playing an important role in regulating protein expression and biological signal transduction. Understanding the regulatory mechanism of SUMOylation can clarify the molecular mechanism of the occurrence and development of neurovascular dysfunction after ABI and is expected to provide a theoretical basis for the development of potential treatment strategies. This article reviews the role of SUMOylation in vascular events related to ABI, including NVU dysfunction and vascular remodeling, and puts forward therapeutic prospects.