122 research outputs found
A Comprehensive Survey on Deep Graph Representation Learning
Graph representation learning aims to effectively encode high-dimensional
sparse graph-structured data into low-dimensional dense vectors, which is a
fundamental task that has been widely studied in a range of fields, including
machine learning and data mining. Classic graph embedding methods follow the
basic idea that the embedding vectors of interconnected nodes in the graph can
still maintain a relatively close distance, thereby preserving the structural
information between the nodes in the graph. However, this is sub-optimal due
to: (i) traditional methods have limited model capacity which limits the
learning performance; (ii) existing techniques typically rely on unsupervised
learning strategies and fail to couple with the latest learning paradigms;
(iii) representation learning and downstream tasks are dependent on each other
which should be jointly enhanced. With the remarkable success of deep learning,
deep graph representation learning has shown great potential and advantages
over shallow (traditional) methods, there exist a large number of deep graph
representation learning techniques have been proposed in the past decade,
especially graph neural networks. In this survey, we conduct a comprehensive
survey on current deep graph representation learning algorithms by proposing a
new taxonomy of existing state-of-the-art literature. Specifically, we
systematically summarize the essential components of graph representation
learning and categorize existing approaches by the ways of graph neural network
architectures and the most recent advanced learning paradigms. Moreover, this
survey also provides the practical and promising applications of deep graph
representation learning. Last but not least, we state new perspectives and
suggest challenging directions which deserve further investigations in the
future
A four-shell, 136-metal 3d-4f heterometallic cluster approximating a rectangular parallelepiped
通讯作者地址: Long, LS (通讯作者), Xiamen Univ, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China
地址:
1. Xiamen Univ, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China
2. Xiamen Univ, Dept Chem, Coll Chem & Chem Engn, Xiamen 361005, Peoples R China
3. Univ Arizona, Dept Chem, Tucson, AZ 85721 USA
4. Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA
电子邮件地址: [email protected], [email protected] nanosized heterometallic cluster containing 60 La(III) and 76 Ni(II) ions, which are arranged into a four-shell, nest-like framework structure, was obtained by the hydrolytic reaction of the mixed La(NO3)(3)-Ni(NO3)(2) system using iminodiacetate as an ancillary ligand to control the hydrolysis.NSF CAREER CHE-0238790
NNSFC 20531050,20721001
MSTC 2007CB81530
An atlas of DNA methylomes in porcine adipose and muscle tissues
It is evident that epigenetic factors, especially DNA methylation, have essential roles in obesity development. Here, using pig as a model, we investigate the systematic association between DNA methylation and obesity. We sample eight variant adipose and two distinct skeletal muscle tissues from three pig breeds living within comparable environments but displaying distinct fat level. We generate 1,381 Gb of sequence data from 180 methylated DNA immunoprecipitation libraries, and provide a genome-wide DNA methylation map as well as a gene expression map for adipose and muscle studies. The analysis shows global similarity and difference among breeds, sexes and anatomic locations, and identifies the differentially methylated regions. The differentially methylated regions in promoters are highly associated with obesity development via expression repression of both known obesity-related genes and novel genes. This comprehensive map provides a solid basis for exploring epigenetic mechanisms of adipose deposition and muscle growth
Keeping the Ball Rolling: Fullerene-like Molecular Clusters
通讯作者地址: Long, LS (通讯作者), Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China
地址:
1. Xiamen Univ, Coll Chem & Chem Engn, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China
2. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, Xiamen 361005, Peoples R China
3. Univ Arizona, Dept Chem, Tucson, AZ 85721 USA
电子邮件地址: [email protected], [email protected] discovery of fullerenes in 1985 opened a new chapter in the chemistry of highly symmetric molecules. Fullerene-like metal dusters, characterized by (multi)shell-like structures, are one rapidly developing class of molecules that share this shape. In addition to creating aesthetically pleasing molecular Structures, the ordered arrangement of metal atoms within such frameworks provides the opportunity to develop materials with properties not readily achieved in corresponding mononuclear or lower-nuclearity complexes.
In this Account, we survey the great variety of fullerene-like metal-containing clusters with an emphasis on their synthetic and structural chemistry, a first step in the discussion of this fascinating field of cluster chemistry. We group the compounds of interest into three categories based on the atomic composition of the cluster core: those with formal metal-metal bonding, those characterized by ligand participation, and those supported by polyoxometalate building blocks. The number of clusters in the first group, containing metal-metal bonds, is relatively small. However, because of the unique and complex bonding scenarios observed for some of these species, these metalloid clusters present a number of research questions with significant ramifications. Because these cores contain molecular clusters of precious metals at the nanoscale, they offer an opportunity to study chemical properties at size ranges from the molecular to nanoscale and to gain insights into the electronic structures and properties of nanomaterials of similar chemical compositions.
Clusters of the second type, whose core structures are facilitated by ligand participation, could aid in the development of functional materials. Of particular interest are the magnetic clusters containing both transition and lanthanide elements. A series of such heterometallic clusters that we prepared demonstrates diverse magnetic properties including antiferromagnetism, ferrimagnetism, and ferromagnetism. Considering the diversity of their composition, their distinct electronic structures, and the disparate coordination behaviors of the different metal elements, these materials suggest abundant opportunities for designing multifunctional materials with varied structures.
The third type of dusters that we discuss are based on polyoxometalates, in particular those containing pentagonal units. However, unlike in fullerene chemistry, which does not allow the use of discrete pentagonal building blocks, the metal oxide-based pentagonal units can be used as fundamental building blocks for constructing various Keplerate structures. These structures also have a variety of functions, including intriguing magnetic properties in some cases. Coupled with different linking groups, such pentagonal units can be used for the assembly of a large number of spherical molecules whose properties can be tuned and optimized.
Although this Account focuses on the topological aspects of fullerene-like metal clusters, we hope that this topical review will stimulate more efforts in the exploratory synthesis of new fullerene-like clusters. More importantly, we hope that further study of the bonding interactions and properties of these molecules will lead to the development of new functional materials.NNSFC 20825103
20531050
20721001
MSTC 2007CB875304
U.S. NSF CHE-023879
Roof Plate-Derived Radial Glial-like Cells Support Developmental Growth of Rapidly Adapting Mechanoreceptor Ascending Axons
Spinal cord longitudinal axons comprise some of the longest axons in our body. However, mechanisms that drive this extra long-distance axonal growth are largely unclear. We found that ascending axons of rapidly adapting (RA) mechanoreceptors closely abut a previously undescribed population of roof plate-derived radial glial-like cells (RGLCs) in the spinal cord dorsal column, which form a network of processes enriched with growth-promoting factors. In dreher mutant mice that lack RGLCs, the lengths of ascending RA mechanoreceptor axon branches are specifically reduced, whereas their descending and collateral branches, and other dorsal column and sensory pathways, are largely unaffected. Because the number and intrinsic growth ability of RA mechanoreceptors are normal in dreher mice, our data suggest that RGLCs provide critical non-cell autonomous growth support for the ascending axons of RA mechanoreceptors. Together, our work identifies a developmental mechanism specifically required for long-range spinal cord longitudinal axons.This work was supported by the NIH (1R01NS083702 and R01NS094224 to W.L., R01NS080390 to K.J.M., R01 NS093009 to V.V.C., and F31-NS100325-01A1 and T32GM07517 to K.K.), and the Klingenstein-Simons Fellowship Awards in the Neurosciences to W.L.Peer reviewe
Eigenvalue analysis of structures with interval parameters using the second-order Taylor series expansion and the DCA for QB
Chiral symmetry breaking by chemically manipulating statistical fluctuation in crystallization
通讯作者地址: Long, LS (通讯作者), Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China
地址:
1. Xiamen Univ, Coll Chem & Chem Engn, Dept Chem, State Key Lab Phys Chem Solid Surface, Xiamen 361005, Peoples R China
电子邮件地址: [email protected], [email protected]
CRISPR/Cas9-mediated genome editing induces exon skipping by alternative splicing or exon deletion
Beauty, Symmetry, and Magnetocaloric Effect-Four-Shell Keplerates with 104 Lanthanide Atoms
通讯作者地址: Kong, XJThe hydrolysis of Ln(ClO4)(3) in the presence of acetate leads to the assembly of the three largest known lanthanide-exclusive cluster complexes, [Nd-104(ClO4)(6)(CH3COO)(60)(mu(3)-OH)(168)(mu(4)-O)(30)(H2O)(112)].(ClO4)(18).(CH3CH2OH)(8).xH(2)O (1, x approximate to 158) and [Ln(104)(ClO4)(6)(CH3COO)(56)(mu(3)-OH)(168)(mu(4)-O)(30)(H2O)(112)].(ClO4)(22).(CH3CH2OH)(2).xH(2)O (2, Ln = Nd; 3, Ln = Gd; x approximate to 140). The structure of the common 104-lanthanide core, abbreviated as Ln(8)@Ln(48)@Ln(24)@Ln(24), features a four-shell arrangement of the metal atoms contained in an innermost cube (a Platonic solid) and, moving outward, three Archimedean solids: a truncated cuboctahedron, a truncated octahedron, and a rhombicuboctahedron. The magnetic entropy change of Delta Sm = 46.9 J kg(-1) K-1 at 2 K for Delta H = 7 T in the case of the Gd-104 cluster is the largest among previously known lanthanide-exclusive cluster compounds.973 Project from the Ministry of Science and Technology of China
2012CB821704
2014CB845601
National Natural Science Foundation of China
21422106
21371144
21431005
21390391
Foundation for the Author of National Excellent Doctoral Dissertation of China
201219
U.S. NSF
APVV-0132-11
3001690
Czech Research Infrastructures
LM201102
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