570 research outputs found
Phenolic compounds and its antioxidant activities in ethanolic extracts from seven cultivars of Chinese jujube
AbstractPhenolic compounds and its antioxidant activity of extracts from seven cultivars of Chinese jujubes were investigated by high performance liquid chromatography (HPLC) with standards and different antioxidant evaluation methods, such as phosphomolybdenum assay, superoxide radical scavenging activity (SRSA), hydroxyl radical scavenging activity (HRSA), antihemolytic activity and inhibition of lipid peroxidation in rat liver homogenate, respectively. The results showed the components of the extracts are comprised of total phenols and flavonoids, and its content ranges from 454.3 to 1298.9 (GAEmg/100g dry weight). Phlorizin, catechin, gallic acid, chlorogenic acid, caffeic acid were the predominant phenolic compounds. All the extracts had significant antioxidant activities either in vitro or in vivo. Correlation analysis indicated that the antioxidant capacities of Chinese jujube extracts demonstrated a good positive relationship with some phenolic acids, which was higher in Xiao and Goutou. The results indicated that Xiao and Goutou could be attributed to a potential source of natural antioxidants for food applications
Interlayer Interactions in Anisotropic Atomically-thin Rhenium Diselenide
Recently, two-dimensional (2D) materials with strong in-plane anisotropic
properties such as black phosphorus have demonstrated great potential for
developing new devices that can take advantage of its reduced lattice symmetry
with potential applications in electronics, optoelectronics and
thermoelectrics. However, the selection of 2D material with strong in-plane
anisotropy has so far been very limited and only sporadic studies have been
devoted to transition metal dichalcogenides (TMDC) materials with reduced
lattice symmetry, which is yet to convey the full picture of their optical and
phonon properties, and the anisotropy in their interlayer interactions. Here,
we study the anisotropic interlayer interactions in an important TMDC 2D
material with reduced in-plane symmetry - atomically thin rhenium diselenide
(ReSe2) - by investigating its ultralow frequency interlayer phonon vibration
modes, the layer dependent optical bandgap, and the anisotropic
photoluminescence (PL) spectra for the first time. The ultralow frequency
interlayer Raman spectra combined with the first study of polarization-resolved
high frequency Raman spectra in mono- and bi-layer ReSe2 allows deterministic
identification of its layer number and crystal orientation. PL measurements
show anisotropic optical emission intensity with bandgap increasing from 1.26
eV in the bulk to 1.32 eV in monolayer, consistent with the theoretical results
based on first-principle calculations. The study of the layer-number dependence
of the Raman modes and the PL spectra reveals the relatively weak van der Waals
interaction and 2D quantum confinement in atomically-thin ReSe2.Comment: 17 pages, 5 figures, supplementary informatio
The effect of bioequivalent radiation dose on survival of patients with limited-stage small-cell lung cancer
GeV antiproton/gamma-ray excesses and the -boson mass anomaly: three faces of GeV dark matter particle?
For the newly discovered -boson mass anomaly, one of the simplest dark
matter (DM) models that can account for the anomaly without violating other
astrophysical/experimental constraints is the inert two Higgs doublet model, in
which the DM mass () is found to be within GeV. In this
model, the annihilation of DM via and would
produce antiprotons and gamma rays, and may account for the excesses identified
previously in both particles. Motivated by this, we re-analyze the AMS-02
antiproton and Fermi-LAT Galactic center gamma-ray data. For the antiproton
analysis, the novel treatment is the inclusion of the charge-sign-dependent
three-dimensional solar modulation model as constrained by the time-dependent
proton data. We find that the excess of antiprotons is more distinct than
previous results based on the force-field solar modulation model. The
interpretation of this excess as the annihilation of () requires a DM mass of () GeV and a
velocity-averaged cross section of . As for the
-ray data analysis, rather than adopting the widely-used spatial
template fitting, we employ an orthogonal approach with a data-driven spectral
template analysis. The fitting to the GeV -ray excess yields DM model
parameters overlapped with those to fit the antiproton excess via the
channel. The consistency of the DM particle properties required to account for
the -boson mass anomaly, the GeV antiproton excess, and the GeV -ray
excess suggest a common origin of them.Comment: 8 page
SNP Variation of RELN Gene and Schizophrenia in a Chinese Population: A Hospital-Based CaseâControl Study
Aims: We aimed to explore whether RELN contributes to the vulnerability and severity of clinical symptoms of schizophrenia (SZ) in a Chinese population.Methods: The following were conducted in an adult Han Chinese population from southern China: caseâcontrol association analyses of 30 representative single nucleotide polymorphisms (SNPs) that were screened according to specific programs based on bioinformatics tools and former research and quantitative trait locus analyses with SNPs and psychiatric symptoms evaluated with the positive and negative symptoms scale.Results: A 4-SNP haplotype consisting of rs362814, rs39339, rs540058, and rs661575 was found to be significantly associated with SZ even after Bonferroni correction (Ď2 = 29.024, p = 6.42E-04, pBonf = 0.017), and the T-C-T-C haplotype was a protective factor for SZ (OR = 0.050, 95% CI = 0.004â0.705). Moreover, the 4-SNP haplotype showed a significant association with G16 (active social avoidance) after false discovery rate correction (Ď2 = 28.620, p = 1.697E-04, pFDR = 0.025). In addition, P7 (hostility) was related to the haplotype comprising rs2229864, rs2535764, and rs262355 (Ď2 = 31.424, p = 2.103E-05, padjustment = 0.019) in quantitative trait loci analyses.Conclusion: Overall, this study showed several positive associations between RELN and SZ, as well as psychiatric symptoms, which not only supports the proposition that RELN is a susceptibility gene for SZ but also provides information on a genotype-phenotype correlation for SZ in a Chinese population
Hypercohones AâC, acylphloroglucinol derivatives with homo-adamantane cores from Hypericum cohaerens
Three new homo-adamantanyl type natural products were derived from polyprenylated polycyclic acylphloroglucinol. Hypercohones A-C (1â3), along with five other known hypercohones (4â8), were isolated from the aerial parts of Hypericum cohaerens. The structures of 1â3 were elucidated on the basis of comprehensive spectroscopic analysis. The inhibitory activities of these isolates against five human cancer cell lines in vitro were tested. [Image: see text] ELECTRONIC SUPPLEMENTARY MATERIAL: Supplementary material is available for this article at 10.1007/s13659-013-0032-9 and is accessible for authorized users
Integrative Genomics Analysis Unravels Tissue-Specific Pathways, Networks, and Key Regulators of Blood Pressure Regulation
Blood pressure (BP) is a highly heritable trait and a major cardiovascular disease risk factor. Genome wide association studies (GWAS) have implicated a number of susceptibility loci for systolic (SBP) and diastolic (DBP) blood pressure. However, a large portion of the heritability cannot be explained by the top GWAS loci and a comprehensive understanding of the underlying molecular mechanisms is still lacking. Here, we utilized an integrative genomics approach that leveraged multiple genetic and genomic datasets including (a) GWAS for SBP and DBP from the International Consortium for Blood Pressure (ICBP), (b) expression quantitative trait loci (eQTLs) from genetics of gene expression studies of human tissues related to BP, (c) knowledge-driven biological pathways, and (d) data-driven tissue-specific regulatory gene networks. Integration of these multidimensional datasets revealed tens of pathways and gene subnetworks in vascular tissues, liver, adipose, blood, and brain functionally associated with DBP and SBP. Diverse processes such as platelet production, insulin secretion/signaling, protein catabolism, cell adhesion and junction, immune and inflammation, and cardiac/smooth muscle contraction, were shared between DBP and SBP. Furthermore, âWnt signalingâ and âmammalian target of rapamycin (mTOR) signalingâ pathways were found to be unique to SBP, while âcytokine networkâ, and âtryptophan catabolismâ to DBP. Incorporation of gene regulatory networks in our analysis informed on key regulator genes that orchestrate tissue-specific subnetworks of genes whose variants together explain ~20% of BP heritability. Our results shed light on the complex mechanisms underlying BP regulation and highlight potential novel targets and pathways for hypertension and cardiovascular diseases
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