118 research outputs found
Distributed Processing of k Shortest Path Queries over Dynamic Road Networks
The problem of identifying the k-shortest paths (KSPs for short) in a dynamic
road network is essential to many location-based services. Road networks are
dynamic in the sense that the weights of the edges in the corresponding graph
constantly change over time, representing evolving traffic conditions. Very
often such services have to process numerous KSP queries over large road
networks at the same time, thus there is a pressing need to identify
distributed solutions for this problem. However, most existing approaches are
designed to identify KSPs on a static graph in a sequential manner (i.e., the
(i+1)-th shortest path is generated based on the i-th shortest path),
restricting their scalability and applicability in a distributed setting. We
therefore propose KSP-DG, a distributed algorithm for identifying k-shortest
paths in a dynamic graph. It is based on partitioning the entire graph into
smaller subgraphs, and reduces the problem of determining KSPs into the
computation of partial KSPs in relevant subgraphs, which can execute in
parallel on a cluster of servers. A distributed two-level index called DTLP is
developed to facilitate the efficient identification of relevant subgraphs. A
salient feature of DTLP is that it indexes a set of virtual paths that are
insensitive to varying traffic conditions, leading to very low maintenance cost
in dynamic road networks. This is the first treatment of the problem of
processing KSP queries over dynamic road networks. Extensive experiments
conducted on real road networks confirm the superiority of our proposal over
baseline methods.Comment: A shorter version of this technical report has been accepted for
publication as a full paper in ACM SIGMOD 2020: International Conference on
Management of Dat
CD40LG and GZMB were correlated with adipose tissue macrophage infiltration and involved in obstructive sleep apnea related metabolic dysregulation: Evidence from bioinformatics analysis
Both obesity and obstructive sleep apnea (OSA) can lead to metabolic dysregulation and systemic inflammation. Similar to obesity, increasing evidence has revealed that immune infiltration in the visceral adipose tissue (VAT) is associated with obstructive sleep apnea-related morbidity. However, the pathological changes and potential molecular mechanisms in visceral adipose tissue of obstructive sleep apnea patients need to be further studied. Herein, by bioinformatics analysis and clinical validation methods, including the immune-related differentially expressed genes (IRDEGs) analysis, protein-protein interaction network (PPI), functional enrichment analysis, a devolution algorithm (CIBERSORT), spearman’s correlation analysis, polymerase chain reaction (PCR), Enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC), we identified and validated 10 hub IRDEGs, the relative mRNA expression of four hub genes (CRP, CD40LG, CCL20, and GZMB), and the protein expression level of two hub genes (CD40LG and GZMB) were consistent with the bioinformatics analysis results. Immune infiltration results further revealed that obstructive sleep apnea patients contained a higher proportion of pro-inflammatory M1 macrophages and a lower proportion of M2 macrophages. Spearman’s correlation analysis showed that CD40LG was positively correlated with M1 macrophages and GZMB was negatively correlated with M2 macrophages. CD40LG and GZMB might play a vital role in the visceral adipose tissue homeostasis of obstructive sleep apnea patients. Their interaction with macrophages and involved pathways not only provides new insights for understanding molecular mechanisms but also be of great significance in discovering novel small molecules or other promising candidates as immunotherapies of OSA-associated metabolic complications
Hetero-Diels–Alder Reaction between Singlet Oxygen and Anthracene Drives Integrative Cage Self-Sorting
A ZnII8L6 pseudocube containing anthracene-centered ligands, a ZnII4L′4 tetrahedron with a similar side length as the cube, and a trigonal prism ZnII6L3L′2 were formed in equilibrium from a common set of subcomponents. Hetero-Diels–Alder reaction with photogenerated singlet oxygen transformed the anthracene-containing “L” ligands into endoperoxide “LO” ones and ultimately drove the integrative self-sorting to form the trigonal prismatic cage ZnII6LO3L′2 exclusively. This ZnII6LO3L′2 structure lost dioxygen in a retro-Diels–Alder reaction after heating, which resulted in reversion to the initial ZnII8L6 + ZnII4L′4 ⇌ 2 × ZnII6L3L′2 equilibrating system. Whereas the ZnII8L6 pseudocube had a cavity too small for guest encapsulation, the ZnII6L3L′2 and ZnII6LO3L′2 trigonal prisms possessed peanut-shaped internal cavities with two isolated compartments divided by bulky anthracene panels. Guest binding was also observed to drive the equilibrating system toward exclusive formation of the ZnII6L3L′2 structure, even in the absence of reaction with singlet oxygen
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