Machine learning has the potential to revolutionize the field of molecular simulation through the development of efficient and accurate models of interatomic interactions. Neural networks can model ...interactions with the accuracy of quantum mechanics-based calculations, but with a fraction of the cost, enabling simulations of large systems over long timescales. However, implicit in the construction of neural network potentials is an assumption of locality, wherein atomic arrangements on the nanometer-scale are used to learn interatomic interactions. Because of this assumption, the resulting neural network models cannot describe long-range interactions that play critical roles in dielectric screening and chemical reactivity. Here, we address this issue by introducing the self-consistent field neural network - a general approach for learning the long-range response of molecular systems in neural network potentials that relies on a physically meaningful separation of the interatomic interactions - and demonstrate its utility by modeling liquid water with and without applied fields.
Based on self-determination theory, we conceptualized the effect of empowering leadership on employee voice
harmonious passion. This paper further explored the moderating effect of job ...characteristics in the voice process and proposed a moderated mediation model. Using a sample of 674 supervisor-subordinate dyads, we found that (1) empowering leadership was positively related to employees' harmonious passion and voice behavior, (2) harmonious passion played a mediating role in the relationship between empowering leadership and employee voice, and (3) job autonomy strengthened the effect of harmonious passion on employee voice, which, in turn, enhanced the mediated relationship between empowering leadership and employee voice
harmonious passion. We discuss the implications of these findings for research and practice.
Titanium (Ti) and its alloys are the most widely used materials for biomedical applications, owing to their good corrosion resistance, mechanical properties, and biocompatibility. However, their ...long-term performance is compromised by the post-surgery complications such as implant-associated infection and mechanical loosening. Surface modification can be adopted to alleviate these concerns while preserving the desirable bulk attributes. Among various techniques, electrochemical methods offer merits such as mild processing conditions, non-line-of-sight operation, low cost, as well as large-scale production. This paper gives a brief overview of surface engineering of the Ti-based alloys from the perspective of electrochemistry. It mainly focuses on three major electrochemical techniques: low voltage anodization, micro-arc oxidation, and electrodeposition. Overall, effects have been made to bring out a comprehensive understanding of electrochemical modification of Ti-based alloys for biomedical applications.
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Anti-CRISPR proteins (Acrs) targeting CRISPR-Cas9 systems represent natural “off switches” for Cas9-based applications. Recently, AcrIIC1, AcrIIC2, and AcrIIC3 proteins were found to inhibit ...Neisseria meningitidis Cas9 (NmeCas9) activity in bacterial and human cells. Here we report biochemical and structural data that suggest molecular mechanisms of AcrIIC2- and AcrIIC3-mediated Cas9 inhibition. AcrIIC2 dimer interacts with the bridge helix of Cas9, interferes with RNA binding, and prevents DNA loading into Cas9. AcrIIC3 blocks the DNA loading step through binding to a non-conserved surface of the HNH domain of Cas9. AcrIIC3 also forms additional interactions with the REC lobe of Cas9 and induces the dimerization of the AcrIIC3-Cas9 complex. While AcrIIC2 targets Cas9 orthologs from different subtypes, albeit with different efficiency, AcrIIC3 specifically inhibits NmeCas9. Structure-guided changes in NmeCas9 orthologs convert them into anti-CRISPR-sensitive proteins. Our studies provide insights into anti-CRISPR-mediated suppression mechanisms and guidelines for designing regulatory tools in Cas9-based applications.
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•Crystal structures of Cas9-bound AcrIICs suggest distinct inhibitory mechanisms•AcrIIC2 interferes with RNA- and DNA-loading steps through binding to Cas9 BH motif•AcrIIC3 induces Cas9 dimerization by interacting with the HNH domain and REC lobe•Cas9 enzymes can be reengineered to become susceptible to AcrIIC’s inhibition
Zhu et al. report biochemical and structural data that suggest molecular mechanisms of AcrIIC2- and AcrIIC3-mediated inhibition of Cas9. The two inhibitors employ distinct means to block Cas9 activity that include binding to different regions, targeting distinct steps of catalysis, and inhibiting different scopes of Cas9 orthologs.
Catalase (CAT) is an antioxidant enzyme expressed by the
gene family and exists in almost all aerobic organisms. Environmental stresses induce the generation of reactive oxygen species (ROS) that ...eventually hinder plant growth and development. The CAT enzyme translates the hydrogen peroxide (H
O
) to water (H
O) and reduce the ROS levels to shelter the cells' death. So far, the
gene family has not been reported in rapeseed (
L.). Therefore, a genome-wide comprehensive analysis was conducted to classify the
genes in the rapeseed genome. The current study identified 14
genes in the rapeseed genome. Based on phylogenetic and synteny analysis, the
belong to four groups (Groups I-IV). A gene structure and conserved motif analysis showed that Group I, Group II, and Group IV possess almost the same intron/exon pattern, and an equal number of motifs, while Group III contains diverse structures and contain 15 motifs. By analyzing the
-elements in the promoters, we identified five hormone-correlated responsive elements and four stress-related responsive elements. Further, six putative bna-miRNAs were also identified, targeting three genes (
and
). Gene ontology (GO) enrichment analysis showed that the
genes were largely related to cellular organelles, ROS response, stimulus response, stress response, and antioxidant enzymes. Almost 10
genes showed higher expression levels in different tissues, i.e., root, leaf, stem, and silique. The expression analysis showed that
and
were significantly upregulated by cold, salinity, abscisic acid (ABA), and gibberellic acid (GA) treatment, but not by drought and methyl jasmonate (MeJA). Notably, most of the genes were upregulated by waterlogging stress, except
, and
. Our results opened new windows for future investigations and provided insights into the
family genes in rapeseed.
1,4,5,8,9,12‐Hexaazatriphenylene (HAT) is one of the smallest polyheterocyclic aromatic building blocks for forming conjugated metal–organic frameworks (cMOFs). However, the strong inter‐molecular ...steric hindrance impedes the growth of HAT‐based cMOFs. Here we employ on‐surface synthesis to grow single‐layer two‐dimensional cMOFs of M3(HAT)2 (M=Ni, Fe, Co). Using scanning tunnelling microscopy and density‐functional theory (DFT) analysis, we resolve that the frameworks comprise a hexagonal lattice of HAT molecules and a Kagome lattice of metal atoms. The DFT analysis indicates that Ni, Co and Fe carry a magnetic moment of 1.1, 2.5, and 3.7 μB, respectively. We anticipate that the small π‐conjugated core of HAT and strong bidentate chelating coordination give rise to appealing electronic and magnetic properties.
1,4,5,8,9,12‐Hexaazatriphenylene (HAT)‐based two‐dimensional conjugated metal–organic frameworks of M3(HAT)2 (M=Fe, Ni, Co) were synthesized by means of an on‐surface self‐assembly protocol which effectively overcomes the strong inter‐molecular steric hindrance.
Abstract
Poly(ethylene oxide)-based solid-state electrolytes are widely considered promising candidates for the next generation of lithium and sodium metal batteries. However, several challenges, ...including low oxidation resistance and low cation transference number, hinder poly(ethylene oxide)-based electrolytes for broad applications. To circumvent these issues, here, we propose the design, synthesis and application of a fluoropolymer, i.e., poly(2,2,2-trifluoroethyl methacrylate). This polymer, when introduced into a poly(ethylene oxide)-based solid electrolyte, improves the electrochemical window stability and transference number. Via multiple physicochemical and theoretical characterizations, we identify the presence of tailored supramolecular bonds and peculiar morphological structures as the main factors responsible for the improved electrochemical performances. The polymeric solid electrolyte is also investigated in full lithium and sodium metal lab-scale cells. Interestingly, when tested in a single-layer pouch cell configuration in combination with a Li metal negative electrode and a LiMn
0.6
Fe
0.4
PO
4
-based positive electrode, the polymeric solid-state electrolyte enables 200 cycles at 42 mA·g
−1
and 70 °C with a stable discharge capacity of approximately 2.5 mAh when an external pressure of 0.28 MPa is applied.
Electrical interactions between bacteria and the environment are delicate and essential. In this study, an external electrical current is applied to capacitive titania nanotubes doped with carbon ...(TNT-C) to evaluate the effects on bacteria killing and the underlying mechanism is investigated. When TNT-C is charged, post-charging antibacterial effects proportional to the capacitance are observed. This capacitance-based antibacterial system works well with both direct and alternating current (DC, AC) and the higher discharging capacity in the positive DC (DC+) group leads to better antibacterial performance. Extracellular electron transfer observed during early contact contributes to the surface-dependent post-charging antibacterial process. Physiologically, the electrical interaction deforms the bacteria morphology and elevates the intracellular reactive oxygen species level without impairing the growth of osteoblasts. Our finding spurs the design of light-independent antibacterial materials and provides insights into the use of electricity to modify biomaterials to complement other bacteria killing measures such as light irradiation.
Oxygen-enriched hierarchical porous carbon (OHPC) is synthesized via an environmentally friendly, facile and cost-effective one-pot pyrolysis of KMnO4@cork composites. The evolution path of KMnO4 and ...its activation mechanism at various stages have been preliminarily understood based on the analysis of XRD data of samples with different synthetic conditions. Benefiting from the synchronous oxidation modification and activation of KMnO4, the as-synthesized OHPC demonstrated a high oxygen content and hierarchical porous structure. The electrochemical measurements revealed that the OHPC electrode in a 6 M KOH three-electrode system exhibited a high specific capacitance of 290 F g−1 at 0.2 A g−1, and retained 210 F g−1 even at 70 A g−1, with a high capacitance retention of 72.4%. The excellent electrochemical performance can be ascribed to the special hierarchical porous structure and abundant content of oxygen (16.8 at%). Further feasibility characterization confirmed that the constructed OHPC-based symmetric supercapacitors demonstrated a high specific capacitance of 242 F g−1 and excellent durability after 10000 cycles (95.2% capacitance retention) in an alkaline 6 M KOH electrolyte, and displayed a high energy density of 14.7 Wh kg−1 in neutral 1 M Na2SO4. This study opens up an environmentally friendly, facile and cost-effective route for the synthesis of biomass derived carbons for advanced energy storage.
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With the development of society and economy, the metro has become one of the essential components of the urban transportation system. Commuting passengers prefer the metro due to its punctual, high ...speeds and uncongested characteristics compared to private cars, taxis, bus, etc., especially in morning and evening rush hour. So, identifying metro commuters and mining its commuting mobility patterns play an essential role in improving service quality, promoting public transit use, and optimizing operational scheduling. We develop a method to mine metro commuting mobility patterns using massive smart card data. Firstly, we extracted individual daily regular OD (origin and destination) based on spatio-temporal similarity measurement from massive smart card data. The information entropy gain algorithm is used to further identify commuters from individual regular OD. Secondly, the station-oriented commute space model is built from space views. Metro stations are divided into employment, residential, and balanced type according to job-housing function pattern. They are divided into high efficiency, general, and low efficiency type according to commute efficiency pattern. Function pattern refers to the proportional relationship between the residence and employment land use around the rail station. Efficiency pattern is a comprehensive index to measure the commute time and distance. Finally, stations are clustered by the K-means method to determine what type they are. The experiment found that metro commuters accounted for 41% of the morning peak traffic using smart card data in Chongqing, China. Three typical job-housing function patterns and three commute efficiency patterns are discovered, respectively, and the characteristics of each are mined.
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