The pollution caused by microplastics in seas and fresh water is of growing environmental concern due to their slow degradability, biological ingestion by fish and other aquatic living organisms, and ...acting as carriers to concentrate and transport synthetic and persistent organic pollutants. As well as microplastics, chemical additives added to plastics during manufacture which may leach out upon ingestion, will enter food chains and potentially cause humans serious health problems.
Regulations in many counties/regions have been setup or to be implemented to ban the production/sale and use of primary microplastics (e.g., microbeads), which could reduce microplastics in the aquatic environment in certain level. However, the fragments from larger plastic items (second microplastics) are major contributors, and then new legislations have to be proposed and implemented in order to substantially reduce the amounts of microplastics in the environment and the associated environmental impact. Moreover, approaches and measures are to be taken by encouraging companies and all users to adopt the Reduce–Reuse–Recycle circular economy as this will represent a cost-effective way of reducing the quantity of plastic objects and microplastics particles entering and gathering in the marine/aquatic environment.
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•Source/distribution and the fate of microplastics in the aquatic environment explored.•Development of microplastics regulations and management policies reviewed.•There is no regulations setup yet to manage the fragments from larger plastic items (second microplastics).•New legislations needed to substantially reduce the amounts of all plastic items into the environment.•Reduce–Reuse–Recycle circular approach is a cost-effective way of reducing the quantity of microplastics.
Recent technological advances have made it possible to decode DNA methylomes at single-base-pair resolution under various physiological conditions. Many aberrant or differentially methylated sites ...have been discovered, but the mechanisms by which changes in DNA methylation lead to observed phenotypes, such as cancer, remain elusive. The classical view of methylation-mediated protein-DNA interactions is that only proteins with a methyl-CpG binding domain (MBD) can interact with methylated DNA. However, evidence is emerging to suggest that transcription factors lacking a MBD can also interact with methylated DNA. The identification of these proteins and the elucidation of their characteristics and the biological consequences of methylation-dependent transcription factor-DNA interactions are important stepping stones towards a mechanistic understanding of methylation-mediated biological processes, which have crucial implications for human development and disease.
Porous materials, especially metal–organic frameworks, covalent organic frameworks, and supramolecular organic frameworks, are widely used in heterogeneous catalysis, adsorption, and ion exchange. ...Cucurbitnurils (Qns) suitable building units for porous materials because they possess cavities with neutral electrostatic potential, portal carbonyls with negative electrostatic potential, and outer surfaces with positive electrostatic potential, which may result in the formation of Qn‐based supramolecular frameworks (QSFs) assembled through the interaction of guests within Qns, the coordination of Qns with metal ions, and outer‐surface interaction of Qns (OSIQ). This review summarizes the various QSFs assembled via OSIQs. The QSFs can be classified as being assembled by 1) self‐induced OSIQ, 2) anion‐induced OSIQ, and 3) aromatic‐induced OSIQ. The design and construction of QSFs with novel structures and specific functional properties may establish a new research direction in Qn chemistry.
This review summarizes the outer‐surface interactions of cucurbitnurils (OSIQ) in various simple cucurbitnuril‐based supramolecular frameworks (QSFs) and QSFs assembled via self‐induced OSIQ, anion‐induced OSIQs, and aromatic‐induced OSIQs. The design and construction of QSFs with novel structures and specific functional properties establishes a new research direction in cucurbitnuril chemistry.
Long-range regulation by distal enhancers is crucial for many biological processes. The existing methods for enhancer-target gene prediction often require many genomic features. This makes them ...difficult to be applied to many cell types, in which the relevant datasets are not always available. Here, we design a tool EAGLE, an enhancer and gene learning ensemble method for identification of Enhancer-Gene (EG) interactions. Unlike existing tools, EAGLE used only six features derived from the genomic features of enhancers and gene expression datasets. Cross-validation revealed that EAGLE outperformed other existing methods. Enrichment analyses on special transcriptional factors, epigenetic modifications, and eQTLs demonstrated that EAGLE could distinguish the interacting pairs from non- interacting ones. Finally, EAGLE was applied to mouse and human genomes and identified 7,680,203 and 7,437,255 EG interactions involving 31,375 and 43,724 genes, 138,547 and 177,062 enhancers across 89 and 110 tissue/cell types in mouse and human, respectively. The obtained interactions are accessible through an interactive database enhanceratlas.org. The EAGLE method is available at https://github.com/EvansGao/EAGLE and the predicted datasets are available in http://www.enhanceratlas.org/.
Supramolecular architectures and materials have attracted immense attention during the last decades because they not only open the possibility of obtaining a large variety of aesthetically ...interesting structures but also have applications in gas storage, sensors, separation, catalysis, and so on. On the other hand, cucurbitnurils (Qns), a relatively new class of macrocyclic hosts with a rigid hydrophobic cavity and two identical carbonyl fringed portals, have attracted much attention in supramolecular chemistry. Because of the strong charge–dipole and hydrogen bonding interactions, as well as hydrophobic and hydrophilic effect derived from the negative portals and rigid cavities of Qns, nearly all research in Qns has been focused on utilizing the portals and cavities to construct supramolecular assemblies similar to other macrocyclic receptors such as cyclodextrin and calixarenes. Interestingly, a recent study revealed that other weak noncovalent interactions such as hydrogen bonding and π···π stacking, as well as C–H···π and ion–dipole interactions, could also be defined as “outer-surface interactions”, which are derived from the electrostatically positive outer surface of Qns. These interactions could be the driving forces in the formation of various novel Qn-based supramolecular architectures and functional materials. In this Account, we provide a comprehensive overview of supramolecular self-assemblies based on the outer-surface interactions of Qns. These outer-surface interactions include those between Qns, Qns and aromatic molecules, Qns and calixarenes, Qns and inorganic complex ions, and Qns and polyoxometalates. Pioneering work has shown that such weak noncovalent interactions play very important roles in the formation of various Qn-based functional materials and supramolecular architectures. For example, hydrogen bonds in outer-surface interactions between Qn molecules not only function as the sole driving force in the formation of one-dimensional Qn porous channels but also assist the bonding forces of the channels in capturing and accommodating acetylene molecules and carbon dioxide in the channel cavities. Moreover, upon introduction of a third species such as an aromatic molecule or inorganic anion into the Qn/metal system, “outer-surface interactions” could lead to Qn/metal-based self-assemblies from simple finite supramolecular coordination complexes to infinite polydimensional supramolecular architectures and other structures. Overall, this Account focuses on the novel self-assembly driving force derived from Qns including (i) concepts of the outer-surface interactions of Qns, (ii) providing plausible explanations of the mechanisms of the outer-surface interactions of Qns, and (iii) introduction of an overview of the developments and practical applications of outer-surface interactions of Qns in supramolecular chemistry. It is hoped that this study based on the outer-surface interactions of Qns can enrich the field of molecular engineering of functional supramolecular systems and provide new opportunities for the construction of functional materials and architectures.
Since 2020, due to the impact of the epidemic, blended teaching has gradually become the mainstream development direction of course teaching. Based on the special attributes of creative thinking, ...online classes are difficult for design disciplines. This study takes the course Brand Image Design of Shanghai Sanda University as a practical object, and explores how to improve the efficiency and student acceptance of blended teaching by combining problem-oriented PBL teaching mode, online course website, online real-time collaborative design platform and other Internet tools.
This paper collects data from worldwide research groups and aims to critically review and analyse the advances of knowledge development in the area of occurrence, transportation, monitoring and ...treatment of emerging micro-pollutants from around the globe and to recommend the research needs in this research area. This review discovers that •A waste water treatment plant is one of pathways for micro-pollutants to transfer into surface waters; •Sample preparation, matrix effects and validation methods are challenges and more advanced analytical instrumentation and procedures are critical in analysing emerging micro-pollutants; •Traditional activated sludge and/or bio-filtration processes showed less efficiency to remove emerging micro-pollutants; •Advanced oxidation processes need to be validated for the efficiency and cost effectiveness; • More researches are needed to classify the type and toxicity of by-products resulting from the reactions between advanced oxidation processes and emerging micro-pollutants. The suggested future research needs from this review are challenges but provide us opportunities to effectively monitor and eliminate emerging micro-pollutants in the environment.
•A waste water treatment plant is one of pathways for micro-pollutants to transfer into surface waters.•Sample preparation, matrix effects and validation methods are challenges in analysing emerging micro-pollutants.•More advanced analytical instrumentation and procedures are critical to tackle micro-pollutants' monitoring.•Traditional activated sludge and/or bio-filtration processes showed less efficiency to remove emerging micro-pollutants.•AOPs need to be validated for the efficiency and cost effectiveness in eliminating emerging micro-pollutants.
Hyperspectral image (HSI) is often disturbed by various kinds of noise, which brings great challenges to subsequent applications. Many of the existing restoration algorithms do not scale well for HSI ...with large size. This paper proposes a novel mixed-noise removal method for HSI with large size, by leveraging the superpixel segmentation-based technology and distributed algorithm based on graph signal processing. First, the underlying structure of the HSI is modeled by a two-layer architecture graph. The upper layer, called skeleton graph, is a rough graph constructed by using the modified k -nearest-neighborhood algorithm and its nodes correspond to a series of superpixels formed by HSI segmentation. The skeleton graph can efficiently characterize the inter-correlations between superpixels, while preserving the boundary information and reducing the computational complexity. The lower layer, called detailed graph consisting of a series of local graphs which are constructed to model the similarities between pixels. Second, based on the two-layer graph architecture, the HSI restoration problem is formulated as a series of optimization problems each of which resides on a subgraph. In each optimization problem, a graph Laplacian regularization is defined and incorporated into a low-rank-based model. Third, a novel distributed algorithm is tailored for the restoration problem, by using the information interaction between the nodes of skeleton graph and subgraphs. Numerical experiments conducted on both synthetic and real-world datasets demonstrate the effectiveness of the proposed restoration algorithm compared with existing methods.
Coordination‐driven self‐assembly is one of the most powerful strategies to prepare nanometer‐sized discrete (supra)molecular assemblies. Herein, we report on the use of two constitutionally isomeric ...BINOL‐based bis(pyridine) ligands for this purpose. Upon coordination to PdII ions these self‐assemble into enantiomerically pure endo‐ and exo‐functionalized hexa‐ and dodecanuclear metallosupramolecular spheres with a chiral skeleton depending on the substitution pattern of the BINOL core. These aggregates were characterized by NMR, MS, DLS, TEM, and EELS as well as ECD. Furthermore, experimental ECD data could be compared to those obtained from theoretical simulations using a simplified Tamm–Dancoff approximation to time‐dependent DFT to rationalize the extraordinary high molar circular dichroisms. Despite the rotational freedom around the central aryl–aryl bond of these ligands, the self‐assembly process happens completely selective in a “narcissistic” self‐recognition manner.
Make mine a sphere: BINOL‐based bis(pyridine) ligands coordinate to PdII ions to form hexa‐ and dodecanuclear enantiomerically pure endo‐ and exo‐functionalized metallosupramolecular spheres. Their chiral skeletons depend on the substitution pattern of the BINOL core. Despite the rotational freedom around the central aryl–aryl bond, the self‐assembly is completely selective in a narcissistic self‐recognition manner.
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