In this Letter we study implications of the possible excess of 21-cm line global signal at the epoch of cosmic dawn on the evolutions of a class of dynamically interacting dark energy (IDE) models. ...We firstly summarize two dynamical mechanisms in which different background evolutions can exert considerable effects on the 21-cm line global signal. One of them is the change in decoupling time of Compton scattering heating, the other stems from the direct change of optical depth due to the different expansion rate of the Universe. After that, we investigate the influence of linear IDE models on 21-cm line signals and find that under the current observational constraints, it is difficult to yield a sufficiently strong 21-cm line signal to be consistent with the results of Experiment to Detect the Global Epoch of reionization Signature (EDGES) since only the optical depth could be effectively changed in these models. Accordingly, this implies us to construct a background evolution which could fulfill the reasonable change of optical depth and Compton heating decoupling time at the same moment by introducing an early dark energy dominated stage into the evolution governed by the IDE models. The comparison with astronomical observations indicate that this scenario could only alleviate, but not complete eliminate, the tension between EDGES and other cosmological surveys.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Three novel compounds (
) along with twenty-six known compounds, two known steroids (
) and twenty-four known phenylpropanoids (
) were isolated from the whole plant of
Turcz. The structures of the ...three new compounds were elucidated on the basis of ESI-MS, HR-ESIMS, 1D and 2D NMR, IR, UV spectroscopic data. The absolute stereochemistry of compound
was determined by the Gauge-Including Atomic Orbitals (GIAO) method. The in vitro antioxidant, anti-inflammatory and cytotoxic activities of the isolated compounds were evaluated by DPPH radical-scavenging assay, LPS-activated RAW 264.7 cells model and CCK-8 kit, respectively. Compound
showed high antioxidant activity with an SC
value of 16.2 ± 1.6 μM. Compound
showed considerable anti-inflammatory activity with an IC
value of 28.6 ± 3.0 μM. Compounds
and
displayed potent cytotoxic activity against human NCI-H292, SiHa, A549, and MKN45 cell lines, with the compound
having IC
values of 17.4 ± 2.4, 22.2 ± 1.1, 9.7 ± 0.9, 9.5 ±0.7 μM, and the compound
having all IC
values less than 0.1 μM in vitro.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•Structural characterization of two polysaccharides from Dendrobium officinale were described.•DOP performed the hypoglycemic activity via stimulating GLP-1 secretion in STZ-induced diabetic rats and ...STC-1 cells.•Ca2+/CaM/CaMKII and MAPK pathways might involve in the intracellular DOP-induced GLP-1 secretion.•The repeated unit of backbone of DOP-1 and DOP-2 might be the effective unit of DOP-induced GLP-1 secretion.
Two polysaccharides, named DOP-1 and DOP-2, with molecular weights of 6.8 kDa and 14.3 kDa, respectively, were isolated and purified from the stems of Dendrobium officinale. Monosaccharide composition, Fourier-transform infrared spectroscopy, methylation, and nuclear magnetic resonance analyses indicated that DOP-1 and DOP-2 may have a backbone consisted of →4)-β-d-Glcp-(1→, →4)-β-d-Manp-(1→, →4)-2-O-acetyl-β-d-Manp-(1→ and →4)-3-O-acetyl-β-d-Manp-(1→. In vivo assays showed that D. officinale polysaccharides (DOPs) exerted significant hypoglycemic effects accompanying increased serum insulin and glucagon-like peptide-1 (GLP-1) levels in streptozotocin-induced diabetic rats. Further in vitro experiments showed that DOP-induced GLP-1 secretion was inhibited by an intracellular calcium chelator, a Ca2+/calmodulin-dependent protein kinase (CaMK) II inhibitor, a specific calcium-sensing receptor antagonist, and a p38-mitogen-activated protein kinases (MAPK) inhibitor. These results indicated that DOPs may decrease fasting blood sugar levels by stimulating GLP-1 secretion and that intracellular DOP-induced GLP-1 secretion involved the Ca2+/calmodulin/CaMKII and MAPK pathways.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In our research on naturally occurring sesquiterpenes, eight shizukaol-type dimers, one chlorahololide-type dimer, and one sarcanolide-type dimer were isolated from the roots of
As the project was ...implemented, we accidentally discovered that shizukaol-type dimers can be converted into peroxidized chlorahololide-type dimers. This potential change was discovered after simulations of the changes in corresponding shizukaols showed that three peroxide products were generated (
), indicating that peroxidation reactions occurred. HPLC-HR-MS analysis results obtained for the shizukaol derivatives further demonstrate that the reaction occurred, and the type of substituent of small organic ester moieties at positions C-15' and C-13' of unit B were not decisively related to the reaction. Quantum chemical calculations of the mode dimer further demonstrated this phenomenon. The highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) energy of the precursor and production revealed the advantageous yield of 4
-hydroperoxyl production. Additionally, the potential reaction mechanism was speculated and validated using the free energy in the reaction which successfully explained the feasibility of the reaction. Finally, the anti-inflammatory activity of the precursors and products was evaluated, and the products of peroxidation showed better anti-inflammatory activity.
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Abstract
We calculate the quasinormal modes (QNM) frequencies of a test massless scalar field and an electromagnetic field around static black holes in
f
(
T
) gravity. Focusing on quadratic
f
(
T
) ...modifications, which is a good approximation for every realistic
f
(
T
) theory, we first extract the spherically symmetric solutions using the perturbative method, imposing two ansätze for the metric functions, which suitably quantify the deviation from the Schwarzschild solution. Moreover, we extract the effective potential, and then calculate the QNM frequency of the obtained solutions. Firstly, we numerically solve the Schrödinger-like equation using the discretization method, and we extract the frequency and the time evolution of the dominant mode applying the function fit method. Secondly, we perform a semi-analytical calculation by applying the WKB method with the Pade approximation. We show that the results for
f
(
T
) gravity are different compared to General Relativity, and in particular we obtain a different slope and period of the field decay behavior for different model parameter values. Hence, under the light of gravitational-wave observations of increasing accuracy from binary systems, the whole analysis could be used as an additional tool to test General Relativity and examine whether torsional gravitational modifications are possible.
The present study aimed to identify the composition of the aerial parts of
L. A chemical investigation on the EtOAc extracts from the aerial parts of
resulted in the isolation of four new ...anthraquinones, namely Cordifoquinone A-D (
-
), along with 16 known anthraquinones. Their structures were elucidated on the basis of NMR and HR-ESIMS data. All isolates were assessed for their inhibitory effects on NO production in LPS-stimulated RAW 264.7 macrophage cells. Compounds
,
and
exhibited significant inhibitory activities with IC
values of 14.05, 23.48 and 29.23 μmol·L
, respectively. Their antibacterial activities of four bacteria,
(ATCC 25922),
subsp.
(ATCC 29213),
subsp.
(ATCC 14028) and
(ATCC 27853), were also evaluated. Our results indicated that the antibacterial activity of these compounds is inactive.
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Abstract
We investigate the scalar perturbations and the possible strong coupling issues of
f
(
T
) around a cosmological background, applying the effective field theory (EFT) approach. We revisit ...the generalized EFT framework of modified teleparallel gravity, and apply it by considering both linear and second-order perturbations for
f
(
T
) theory. We find that no new scalar mode is present in both linear and second-order perturbations in
f
(
T
) gravity, which suggests a strong coupling problem. However, based on the ratio of cubic to quadratic Lagrangians, we provide a simple estimation of the strong coupling scale, a result which shows that the strong coupling problem can be avoided at least for some modes. In conclusion, perturbation behaviors that at first appear problematic may not inevitably lead to a strong coupling problem, as long as the relevant scale is comparable with the cutoff scale
M
of the applicability of the theory.
Immune and inflammatory responses have an important function in the pathophysiology of pulmonary hypertension (PH). However, little is known about the immune landscape in peripheral circulation in ...patients with high-altitude pulmonary hypertension (HAPH). We apply single-cell transcriptomics to characterize the monocytes that are significantly enriched in the peripheral blood mononuclear cells (PBMC) of HAPH patients. We discover an increase in C1 (non-classical) and C2 (intermediate) monocytes in PBMCs and a decrease in hypoxia-inducible transcription factor-1α (HIF-1α) in all monocyte subsets associated with HAPH. In addition, we demonstrate that similar immune adaptations may exist in HAPH and PH. Overall, we characterize an immune cell atlas of the peripheral blood in HAPH patients. Our data provide evidence that specific monocyte subsets and HIF-1α downregulation might be implicated in the pathogenesis of HAPH.
We study the equivalence principle, regarded as the cornerstone of general relativity, by analyzing the deformation observable of black hole shadows. Such deformation can arise from new physics and ...may be expressed as a phenomenological violation of the equivalence principle. Specifically, we assume that there is an additional background vector field that couples to the photons around the supermassive black hole. This type of coupling yields impact on the way the system depends on initial conditions and affects the black hole shadow at different wavelengths by a different amount, and therefore observations of the shadow in different wavelengths could constrain such couplings. This can be tested by future multiband observations. Adopting a specific form of the vector field, we obtain constraints on model parameters from Event Horizon Telescope observations and measurements of gas/stellar orbits.
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Eleven previously unreported compounds (1–11), including five diterpenoids (1–5) and six sesquiterpenoids (6–11), together with two known diterpenoids (12–13), have been isolated from the roots of ...Salvia prattii. Their structures were comprehensively elucidated through spectroscopic methods, and their configurations were established using computational 13C nuclear magnetic resonance and electronic circular dichroism. Compound 1 was found to be an abietane-type diterpenoid with a novel rearrangement generated from the cleavage of the C-4/5 chemical bond, 20-methyl shift, and the rearrangement of the C-10 side chain. Compounds 2–3 were the third and fourth examples of arrangement seco-norabietanes with a spiro-lactone ring. We evaluated all compounds for their protective effects against alcoholic liver diseases (ALD). Compound 2 exhibited potential protective activity and hence can be used as a novel anti-ALD candidate.
Five previously undescribed abietane-type diterpenoids, and six previously unreported sesquiterpenoids were isolated from the roots of Salvia prattii. Compound 2 exhibited potent protective effects against ethanol induced AML-12 cells. Display omitted
•Five previously undescribed abietane-type diterpenoids, and six previously unreported sesquiterpenoids were isolated from the roots of Salvia prattii.•The absolute configurations were determined by computational NMR and electronic circular dichroism method.•Compound 2 showed potential protective effect against alcoholic liver disease.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
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