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This work reports the amine and mercapto bi-functionalized mesoporous silica MCM-41 for heavy metal ions removal from aqueous solutions. XRD, FTIR and N2 adsorption–desorption analyses confirmed that a series of bi-functionalized mesoporous silica MCM-41 with huge specific surface area were successfully obtained. In aqueous solution, the adsorption performance were evaluated by the adsorption of Zn(II), Cu(II), Cr(III) and Pb(II). The obtained results indicate that synthesis process has no significant influence on the structure and the existence of functional group resulted in outstanding adsorption capacity. The methodology of pre-hydrolysis was one effective treatment for grafting useful functional group on to mesoporous silica. The adsorption reactions for the adsorption of heavy metal ions by bi-functionalized silica-based mesoporous materials were spontaneous adsorption processes over the range of experimental temperatures. The adsorption isotherm is consistent with the Freundlich adsorption isotherms model. The Freundlich parameters KF and n indicated favorable adsorption. The adsorption kinetics of heavy metalions over these bi-functionalized mesoporous silica could be well described by pseudo-second-order models. Therefore, this bi-functionalized mesoporous material has promise for the removal and recovery of heavy metal ions from water. [ABSTRACT FROM AUTHOR]

Group B Streptococcus (GBS) is a major cause of pneumonia, sepsis, and meningitis in infants younger than 3 months of age. Furthermore, GBS infection in pregnant women is associated with stillbirths and pre-term delivery. It also causes disease in immunocompromised adults and the elderly, but the highest incidence of the disease occurs in neonates and young infants. At this time, there are no licensed vaccines against GBS. Complete GBS genome sequencing has helped identify genetically conserved and immunogenic proteins, which could serve as vaccine immunogens. In this study, in silico reverse vaccinology method were used to evaluate the prevalence and conservation of GBS proteins in invasive and colonizing isolates from South African infants and women, respectively. Furthermore, this study aimed to predict potential GBS vaccine targets by evaluating metrics such as antigenicity, physico-chemical properties, subcellular localization, secondary and tertiary structures, and epitope prediction and conservation. A total of 648 invasive and 603 colonizing GBS isolate sequences were screened against a panel of 89 candidate GBS proteins. Ten of the 89 proteins were highly genetically conserved in invasive and colonizing GBS isolates, nine of which were computationally inferred proteins (gbs2106, SAN_1577, SAN_0356, SAN_1808, SAN_1685, SAN_0413, SAN_0990, SAN_1040, SAN_0226) and one was the surface Immunogenic Protein (SIP). Additionally, the nine proteins were predicted to be more antigenic than the SIP protein (antigenicity score of > 0.6498), highlighting their potential as GBS vaccine antigen targets. [ABSTRACT FROM AUTHOR]

Trace element levels in the circulation (blood, serum, plasma) are believed to play a role in the pathophysiologic processes of Alzheimer's disease (AD); however, there is heterogeneity in the available findings. This study conducted a systematic review and meta-analysis of trace elements (including: copper (Cu), iron (Fe), zinc (Zn), selenium (Se), lead (Pb), cadmium (Cd), mercury (Hg), manganese (Mn), aluminum (Al), arsenic (As), and magnesium (Mg)) in AD patients and controls to assess the variation of trace elements in the circulation of AD patients. By systematically screening case–control studies on circulatory trace element levels in AD patients from 2000 to the present in the PubMed, Web of Science, and MEDLINE databases, 52 studies were included in the final meta-analysis. The results of the random-effects model showed significantly elevated circulatory levels of Cd (SMD = 0.79, 95% CI: 0.35, 1.24), Hg (SMD = 0.59, 95% CI: 0.03, 1.16), and Cu (SMD = 0.70, 95% CI: 0.37, 1.04) in AD patients, while levels of Fe (SMD = − 0.58, 95% CI: − 1.03, − 0.13), Se (SMD = − 0.53, 95% CI: − 0.85, − 0.21), and Zn (SMD = − 0.99, 95% CI: − 1.52, − 0.46) were significantly lower. The database formed in this study provides reliable population-based research evidence for exploring changes in circulating trace element levels in AD patients. Monitoring and stabilization of circulatory trace element levels in the elderly may be a potential preventive target for AD. [ABSTRACT FROM AUTHOR]

Electrocatalytic alkynes semi-hydrogenation to produce alkenes with high yield and Faradaic efficiency remains technically challenging because of kinetically favorable hydrogen evolution reaction and over-hydrogenation. Here, we propose a hierarchically nanoporous Cu50Au50 alloy to improve electrocatalytic performance toward semi-hydrogenation of alkynes. Using Operando X-ray absorption spectroscopy and density functional theory calculations, we find that Au modulate the electronic structure of Cu, which could intrinsically inhibit the combination of H* to form H2 and weaken alkene adsorption, thus promoting alkyne semi-hydrogenation and hampering alkene over-hydrogenation. Finite element method simulations and experimental results unveil that hierarchically nanoporous catalysts induce a local microenvironment with abundant K+ cations by enhancing the electric field within the nanopore, accelerating water electrolysis to form more H*, thereby promoting the conversion of alkynes. As a result, the nanoporous Cu50Au50 electrocatalyst achieves highly efficient electrocatalytic semi-hydrogenation of alkynes with 94% conversion, 100% selectivity, and a 92% Faradaic efficiency over wide potential window. This work provides a general guidance of the rational design for high-performance electrocatalytic transfer semi-hydrogenation catalysts. Electrocatalytic alkyne semi-hydrogenation to alkenes is challenging due to the hydrogen evolution competing reaction and over-hydrogenation. Here, the authors report Cu50Au50 alloy for high selectivity towards styrene production. [ABSTRACT FROM AUTHOR]

The Chungtien schizothoracin (Ptychobarbus chungtienensis), an endangered fish species endemic to the Zhongdian Plateau, remains underexplored in terms of transcriptomic sequencing. This investigation used tissues from five distinct organs (heart, liver, spleen, kidney, and brain) of the Chungtien schizothoracin for PacBio Iso-seq and RNA-seq analyses, yielding a repertoire of 16,598 full-length transcripts spanning lengths from 363 bp to 7,157 bp. Gene family clustering and phylogenetic analysis encompassed a comprehensive set of 13 fish species, all of which were cyprinids, including the zebrafish and the examined species Ptychobarbus chungtienensis. Moreover, the identification of long non-coding RNAs (lncRNAs) and coding sequences was accomplished across all five tissues. Comprehensive analyses of gene expression profiles and differentially expressed genes among the above five tissues were performed. In summary, the obtained full-length transcripts and detailed gene expression profiles of the Chungtien schizothoracin tissues furnish crucial expression data and genetic sequences, laying the groundwork for future investigations and fostering a holistic comprehension of the adaptive mechanisms inherent in the Chungtien schizothoracin under various conditions. [ABSTRACT FROM AUTHOR]

Factor-dependent termination uses molecular motors to remodel transcription machineries, but the associated mechanisms, especially in eukaryotes, are poorly understood. Here we use single-molecule fluorescence assays to characterize in real time the composition and the catalytic states of Saccharomyces cerevisiae transcription termination complexes remodeled by Sen1 helicase. We confirm that Sen1 takes the RNA transcript as its substrate and translocates along it by hydrolyzing multiple ATPs to form an intermediate with a stalled RNA polymerase II (Pol II) transcription elongation complex (TEC). We show that this intermediate dissociates upon hydrolysis of a single ATP leading to dissociation of Sen1 and RNA, after which Sen1 remains bound to the RNA. We find that Pol II ends up in a variety of states: dissociating from the DNA substrate, which is facilitated by transcription bubble rewinding, being retained to the DNA substrate, or diffusing along the DNA substrate. Our results provide a complete quantitative framework for understanding the mechanism of Sen1-dependent transcription termination in eukaryotes. Here, the authors report the kinetics of Sen1/RNA simultaneous release, Sen1-Pol II complex dissociation, and Pol II diffusion during eukaryotic Sen1-dependent transcription termination through single-molecule fluorescence assays. [ABSTRACT FROM AUTHOR]

A comprehensive evaluation of collagen-based historical artifacts is crucial for the preservation and inheritance of cultural relics, necessitating interdisciplinary approaches that integrate scientific knowledge with practical expertise to develop effective conservation strategies. The present work was focused on a piece of historical leather armor housed in Turpan Museum, Xinjiang, China. SEM–EDS, XRD, ATR-FTIR, and NMR were carried out on this historical leather armor from macro and micro perspectives, mainly including morphology observation, composition analysis, structural assessment, which could provide both quantitative and qualitative insights into the deterioration of the historical leather armor. Additionally, the non-destructive sampling methods and the third-generation sequencing technology (TGS) were employed to identify a total of 13 bacterial species and 8 fungal species, and their metabolic pathways were predicted, providing guidance for preventive conservation and restoration strategies. By the present work, necessary fundamental knowledge might be provided for the effective preservation and inheritance of collagen-based historical artifacts. [ABSTRACT FROM AUTHOR]

The effects of Er content on microstructures and mechanical properties of Er-doped CoCrNi medium entropy alloys (MEAs) were studied in this work. A series of Er-doped CoCrNi MEAs with 0, 0.1, 0.3, 0.5, 0.7, 1.0, and 1.3 at.% Er was fabricated by high-vacuum arc melting. It was found that Er element addition led to the formation of Er-Ni riched hexagonal phase (CaCu5 type) precipitates embedded in the original FCC matrix. The volume fraction of the HCP phase increased with the increasing Er content. The grain size decreased from 18.1 to 5.1 µm as the Er content increased from 0 to 1.3 at.%. Both the ultimate tensile strength (UTS) and Vickers hardness increased with the increasing Er content, while the ductility decreased. Compared to CoCrNi MEA, the UTS and Vickers hardness of (CoCrNi)98.7Er1.3 MEA increased from 878 to 1143 MPa and 212 to 263 HV, respectively. In addition, the nanoindentation measurements on different phases indicated that the HCP precipitates had a high hardness (~ 7.87 GPa), which was almost two times of that of the FCC matrix (~ 4.72 GPa). The strengthening mechanisms included solid-solution, grain refinement, and precipitation strengthenings. [ABSTRACT FROM AUTHOR]

Background: Although phytoplankton are important primary producers in food webs, they are relatively less studied in large rivers compared to other types of systems. To fill this research gap, we studied phytoplankton taxonomic and functional composition and their relationships with water quality, habitat, climate, and land use across 30 river sections in the middle and lower reaches of the Yangtze River during 2017–2018. Results: Major observed phytoplankton groups were cyanobacteria, bacillariophyta, and chlorophyta. Phytoplankton total abundance, total biomass, and species richness significantly decreased in the dry season compared to the wet season, with the species and functional composition differing significantly between seasons. Phytoplankton species differences between seasons were mainly contributed by Oscillatoria sp., Pseudanabaena sp., and Melosira granulata. The dfferences in phytoplankton functional groups between seasons were mainly contributed by P (including Closterium sp., Melosira sp.), Lo (including Merismopedia sp., Peridinium sp., Ceratium sp., and Gymnodinium sp.), and J (including Pediastrum sp., Tetraedron sp., Crucigenia sp., Scenedesmus sp., and Coelastrum sp.). The variance partitioning showed that water quality (NO3-N, total suspended solids, turbidity) and habitat (water flow, river bank and river channel conditions) were critical factors in shaping phytoplankton patterns, followed by climate and land use. Conclusions: Results indicated that there was significant seasonal variation of phytoplankton in the Yangtze River, with water quality and habitat primarily driving phytoplankton patterns. Our study contributes to the understanding of natural and anthropogenic factors that drive seasonal successional processes of phytoplankton in the Yangtze River. These findings have important implications for environmental management as well as towards the ecological restoration of large rivers. [ABSTRACT FROM AUTHOR]

In the face of growing global tendencies of anti-globalization and de-globalization, emerging economy multinational enterprises (EMNEs) are suffering from a trust deficit and multiple liabilities of foreignness in leading economies. The purpose of this study is to empirically examine the coping strategies of EMNEs towards the challenging institutional environment in host countries. It adopts a qualitative approach, conducting longitudinal multiple cases studies among MNE subsidiaries and employing interviews as the main method of data collection. The findings reveal that EMNEs are not passive recipients of the adverse institutional environment and adopt institutional adaptation as the only response strategy. Given that a single strategy cannot be effective, they have developed both proactive and protective strategies to handle the multiple liabilities of foreignness and trust deficit. This study can help EMNEs gain a better understanding of the dominance effect and develop more effective measures to manage challenging institutional environments in host countries. Given that interactions between institutional environments and firm-level strategies of MNEs remain under-researched, this study advances understanding of strategies and behaviours of MNEs in host countries. [ABSTRACT FROM AUTHOR]

A recent single-cell survey of the small-intestinal epithelium suggests that mucosal pentraxin 2 (Mptx2) is a new Paneth cell marker, but its function and involved mechanism in the Paneth cell are still unknown. Therefore, we create Mptx2 knockout (Mptx2−/−) mice to investigate its precise effects on intestinal homeostasis using models of lipopolysaccharide (LPS), methicillin-resistant Staphylococcus aureus (MRSA) peritoneal infection, and dextran sulfate sodium (DSS)–induced intestinal injury and inflammation. We here find that Mptx2 is selectively expressed in Paneth cells in the small intestines of mice. Mptx2−/− mice have increased susceptibility to intestinal inflammation and injured. Mptx2 deficiency reduces Paneth cell count and expression of antimicrobial factors, leading to altered intestinal bacteria composition. Loss of Mptx2 aggravates MRSA infection–induced damage in the intestine while decreasing autophagy in Paneth cells. Mptx2−/− mice are more vulnerable to LPS-induced intestinal possibly due to inhibition of the autophagy/endoplasmic reticulum (ER) stress pathway. Mptx2−/− mice are susceptible to DSS-induced colitis that could be ameliorated by treatment with gentamicin or vancomycin antibiotics. In conclusion, Mptx2 is essential to maintain intestinal homeostasis potentially via regulation of autophagy in Paneth cells. Mucosal pentraxin 2 (Mptx2) is identified as a marker of Paneth cells, and its deficiency is shown to trigger microbiota dysbiosis and increased epithelial invasion by bacteria while also reducing secretory autophagy. [ABSTRACT FROM AUTHOR]

Monolayer molybdenum disulfide (MoS2), an emergent two-dimensional (2D) semiconductor, holds great promise for transcending the fundamental limits of silicon electronics and continue the downscaling of field-effect transistors. To realize its full potential and high-end applications, controlled synthesis of wafer-scale monolayer MoS2 single crystals on general commercial substrates is highly desired yet challenging. Here, we demonstrate the successful epitaxial growth of 2-inch single-crystal MoS2 monolayers on industry-compatible substrates of c-plane sapphire by engineering the formation of a specific interfacial reconstructed layer through the S/MoO3 precursor ratio control. The unidirectional alignment and seamless stitching of MoS2 domains across the entire wafer are demonstrated through cross-dimensional characterizations ranging from atomic- to centimeter-scale. The epitaxial monolayer MoS2 single crystal shows good wafer-scale uniformity and state-of-the-art quality, as evidenced from the ~100% phonon circular dichroism, exciton valley polarization of ~70%, room-temperature mobility of ~140 cm2v−1s−1, and on/off ratio of ~109. Our work provides a simple strategy to produce wafer-scale single-crystal 2D semiconductors on commercial insulator substrates, paving the way towards the further extension of Moore’s law and industrial applications of 2D electronic circuits.2D MoS2 is being intensively investigated as a promising candidate to extend the downscaling of electronic devices. Here, the authors report a buffer-layer-control method for the growth of wafer-scale single-crystalline MoS2 monolayers on industry-compatible sapphire substrates with competitive optical and electronic properties. [ABSTRACT FROM AUTHOR]

To solve the problem of excessive carbon emission and protect the environment, the government has put forward cap-and-trade (CAT) policy to limit the greenhouse gas. In order to testify the efficiency of the CAT policy and different coordinating contracts, this paper develops a closed-loop supply chain (CLSC) model consisting of a single manufacturer and retailer under various coordination scenarios. We establish a Stackelberg game model for the manufacturer and the retailer to explore the impact of the CAT policy on pricing, profits and social welfare under different contracts. Our research finds the following conclusions: (1) The CAT policy outperforms the situation with no CAT policy regarding environment, collection quantity and profit; (2) for the profits of manufacturers and CLSC, the profit-sharing contract is optimal, while the retailers may obtain the lowest interest compared with other contracts; (3) the environment benefits and the consumer surplus present contradictory relationships in the contracts. The research objectives are to find out the most appropriate strategies of CAT policy for enterprises in CLSC and improve society's utility at the same time. These findings provide instructive and practical insights for equilibrium supply chains. [ABSTRACT FROM AUTHOR]

As the wafer process becomes more complex, the probability of mixed-type defective wafer maps is constantly increasing. Therefore, it is necessary to perform effective filtering and denoising processing on the mixed-type defective wafer map to facilitate the identification. We propose a Neighborhood Path Filtering Clustering (NPFC) algorithm in this paper. For determining the number of clusters in the wafer map, we combine the clustering index of the Silhouette coefficient and the similarity index of Mahalanobis distance to propose a clustering similarity index SD. Then, calculating the compactness index between the clusters is judged whether the clusters are merged or not, to obtain the final clustering effect. The greatest advantage of this method is that it avoids the influence of algorithm parameter settings on the filtering effectiveness. Meanwhile, it can still effectively identify clusters of arbitrary shapes. The experimental results show that compared with median filtering, K-mean clustering and adjacency clustering, the NPFC algorithm achieves good results in the filtering and clustering effect. [ABSTRACT FROM AUTHOR]