The keto-enol tautomerisation in homophthalic anhydride (HA) is investigated in the ground (S
0
) and excited (S
1
) electronic states. The keto form with a dicarbonyl structure is found to be the ...most stable form in S
0
and enol form with a monocarbonyl structure in S
1
indicating an excited state intramolecular proton transfer (ESIPT) process. The computed results show consistency with the change in basis sets and methods of calculations. Apart from the two tautomers, transition states are also identified. The barrier to interconversion is found to reduce substantially in S
1
. Internal reaction coordinate (IRC) calculations confirm the pathway of interconversion between the two forms in S
0
and S
1
. The observed FT-IR spectra corroborate well with our computed spectra. The appearance of two strong lines around 1800 cm
−1
confirms the lowest energy structure to be the keto tautomer with a dicarbonyl form in S
0
. Our computations corroborate well with the crystal structure data for an analogous molecule. Electron distribution in HOMO and LUMO indicate the excitation process as π → π
*
in nature. The qualitative chemical concepts like hardness and electrophilicity are calculated to estimate the stability of the tautomers. The energy and hardness profiles with the variation of IRC are opposite to each other, verifying the principle of maximum hardness.
For centuries, national economies have been engaging in international trade and production. The resulting international supply networks not only increase wealth for countries, but also allow for ...economic shocks to propagate across borders. Using global, firm-level supply network data, we estimate a country's exposure to direct and indirect economic losses caused by the failure of a company in another country. We show the network of international systemic risk-flows. We find that rich countries expose poor countries stronger to systemic risk than vice-versa. The risk is highly concentrated, however, higher risk levels are not compensated with a risk premium in GDP levels, nor higher GDP growth. Our findings put the often praised benefits for developing countries from globalized production in a new light, by relating them to risks involved in the production processes. Exposure risks present a new dimension of global inequality that most affects the poor in supply shock crises.
This paper studies the structure of the Japanese production network, which includes one million firms and five million supplier-customer links. This study finds that this network forms a tightly-knit ...structure with a core giant strongly connected component (GSCC) surrounded by IN and OUT components constituting two half-shells of the GSCC, which we call awalnut structure because of its shape. The hierarchical structure of the communities is studied by the Infomap method, and most of the irreducible communities are found to be at the second level. The composition of some of the major communities, including overexpressions regarding their industrial or regional nature, and the connections that exist between the communities are studied in detail. The findings obtained here cause us to question the validity and accuracy of using the conventional input-output analysis, which is expected to be useful when firms in the same sectors are highly connected to each other.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Inter-firm organizations, which play a driving role in the economy of a country, can be represented in the form of a customer–supplier network. Such a network exhibits a heavy-tailed degree ...distribution, disassortative mixing and a prominent community structure. We analyze a large-scale data set of customer–supplier relationships containing data from one million Japanese firms. Using a directed network framework, we show that the production network exhibits the characteristics listed above. We conduct detailed investigations to characterize the communities in the network. The topology within smaller communities is found to be very close to a tree-like structure but becomes denser as the community size increases. A large fraction (∼40%) of firms with relatively small in- or out-degrees have customers or suppliers solely from within their own communities, indicating interactions of a highly local nature. The interaction strengths between communities as measured by the inter-community link weights follow a highly heterogeneous distribution. We further present the statistically significant over-expressions of different prefectures and sectors within different communities.
•The community structure is uncovered in a large-scale directed production network.•We conduct a detailed topological characterization of the communities.•A heterogeneous distribution of inter-modular link weights is observed.•Significant over-expressions of prefectures and sectors is detected across communities.
Cryptoassets are becoming essential in the digital economy era. XRP is one of the large market cap cryptoassets. Here, we develop a novel method of correlation tensor spectra for the dynamical XRP ...networks, which can provide an early indication for XRP price. A weighed directed weekly transaction network among XRP wallets is constructed by aggregating all transactions for a week. A vector for each node is then obtained by embedding the weekly network in continuous vector space. From a set of weekly snapshots of node vectors, we construct a correlation tensor. A double singular value decomposition of the correlation tensors gives its singular values. The significance of the singular values is shown by comparing with its randomize counterpart. The evolution of singular values shows a distinctive behavior. The largest singular value shows a significant negative correlation with XRP/USD price. We observe the minimum of the largest singular values at the XRP/USD price peak during the first week of January 2018. The minimum of the largest singular value during January 2018 is explained by decomposing the correlation tensor in the signal and noise components and also by evolution of community structure.
In 1993, the discovery of microRNAs in
(
) altered the paradigmatic view of RNA biology and post-transcriptional gene regulation. Further study revealed the role of microRNAs in disease development ...and progression. In particular, this review highlights microRNA-223 (miR-223 or miRNA-223) expression in malignant neoplastic disorders. miR-223 expression controls aspects of hematopoiesis and apoptosis, and cell proliferation, migration, and invasion. miR-223 regulates a number of gene targets, including cytoplasmic activation/proliferation-associated protein-1 (Caprin-1), insulin-like growth factor-1 receptor (IGF-1R), and other cell proliferation- and cell cycle-associated genes. Several studies have proposed miR-223 as a novel biomarker for early cancer diagnosis. Here, we emphasize miR-223's role in the development and progression of cancer.
Hi-C is currently the most widely used assay to investigate the 3D organization of the genome and to study its role in gene regulation, DNA replication, and disease. However, Hi-C experiments are ...costly to perform and involve multiple complex experimental steps; thus, accurate methods for measuring the quality and reproducibility of Hi-C data are essential to determine whether the output should be used further in a study.
Using real and simulated data, we profile the performance of several recently proposed methods for assessing reproducibility of population Hi-C data, including HiCRep, GenomeDISCO, HiC-Spector, and QuASAR-Rep. By explicitly controlling noise and sparsity through simulations, we demonstrate the deficiencies of performing simple correlation analysis on pairs of matrices, and we show that methods developed specifically for Hi-C data produce better measures of reproducibility. We also show how to use established measures, such as the ratio of intra- to interchromosomal interactions, and novel ones, such as QuASAR-QC, to identify low-quality experiments.
In this work, we assess reproducibility and quality measures by varying sequencing depth, resolution and noise levels in Hi-C data from 13 cell lines, with two biological replicates each, as well as 176 simulated matrices. Through this extensive validation and benchmarking of Hi-C data, we describe best practices for reproducibility and quality assessment of Hi-C experiments. We make all software publicly available at http://github.com/kundajelab/3DChromatin_ReplicateQC to facilitate adoption in the community.
Background
Helicobacter pylori
(
H. pylori
) has been recognized as the class I carcinogen of gastric cancer and several studies have demonstrated that chronic stress may accelerate gastric cancer ...progression. However, the evidence is not sufficient.
Methods
Here, we developed a mouse model that combined
H. pylori
infection with chronic stress. Gastric inflammation promotes gastric tumor development progression. To evaluate the number of pro-inflammatory cells through observing the numbers of activated macrophages and neutrophils in mice gastric tumors compared with untreated mice or only treated with one factor. ADRα1d /SerpinA1 expression and localization were assessed under stress conditions and
H. pylori
infection, and evaluated by analyzing IL-1α, CD8, platelet, and RBC status using α- or β- blockers against gastritis to prevent gastric cancer.
Results
Further mechanism study showed that stress hormones increase the number of CD8
+
lymphocytes by activating ADRβ2 receptors, leading to IL-1α secretion and tumorigenicity. Gastric carcinogenesis also involves gastric muscle contraction mediated through ADRα1d/Serpina1 interaction. Specifically, we showed that the ADRα1d/SerpinA1 complex increases glucose uptake and the development of hypoxia conditions. These responses promote platelet aggregation and muscle contraction. In turn, gastric cancer cells increase lactate production and promote gastric cell proliferation through Muc-13 and IL-1α stimulation.
Conclusion
H. pylori
infection in combination with chronic stress can lead to gastric cancer, and the synergistic effects of cytokine production (i.e. IL-1α), T lymphocyte dysfunction contributes to gastric carcinogenesis which will offer treatment opportunities for stress-associated gastric cancer and provide new strategies for the prevention and treatment of gastric cancer in clinics.
Graphical abstract
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