3,583 research outputs found
An Efficient Process for Pretreatment of Lignocelluloses in Functional Ionic Liquids
Background and Aims. The complex structure of the lignocelluloses is the main obstacle in the conversion of lignocellulosic biomass into valuable products. Ionic liquids provide the opportunities for their efficient pretreatment for biomass. Therefore, in this work, pretreatment of corn stalk was carried out in ultrasonic-assisted ionic liquid including 1-butyl-3-methylimidazolium chloride [BMIM]Cl, 1-H-3-methylimidazolium chloride [HMIM]Cl, and 1-(1-propylsulfonic)-3-imidazolium chloride [HSO3-pMIM]Cl at 70°C for 2 h. We compared the pretreatments by ionic liquid with and without the addition of deionized water. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were employed to analyze the chemical characteristics of regenerated cellulose-rich materials. Results. [HMIM]Cl and [HSO3-pMIM]Cl were effective in lignin extraction to obtain cellulose-rich materials. FTIR analysis and SEM analysis indicated the effective lignin removal and the reduced crystallinity of cellulose-rich materials. Enzymatic hydrolysis of cellulose-rich materials was performed efficiently. High yields of reducing sugar and glucose were obtained when the corn stalk was pretreated by [HMIM]Cl and [HSO3-pMIM]Cl. Conclusions. Ionic liquids provided the ideal environment for lignin extraction and enzymatic hydrolysis of corn stalk and [HMIM]Cl and [HSO3-pMIM]Cl proved the most efficient ionic liquids. This simple and environmentally acceptable method has a great potential for the preparation of bioethanol for industrial production
Constraining the cosmological parameters using gravitational wave observations of massive black hole binaries and statistical redshift information
Space-borne gravitational wave detectors like TianQin are expected to detect
GW signals emitted by the mergers of massive black hole binaries. Luminosity
distance information can be obtained from GW observations, and one can perform
cosmological inference if redshift information can also be extracted, which
would be straightforward if an electromagnetic counterpart exists. In this
paper, we concentrate on the conservative scenario where the EM counterparts
are not available, and comprehensively study if cosmological parameters can be
inferred through a statistical approach, utilizing the non-uniform distribution
of galaxies as well as the black hole mass-host galaxy bulge luminosity
relationship. By adopting different massive black hole binary merger models,
and assuming different detector configurations, we conclude that the
statistical inference of cosmological parameters is indeed possible. TianQin is
expected to constrain the Hubble constant to a relative error of about 4%-7%,
depending on the underlying model. The multidetector network of TianQin and
LISA can significantly improve the precision of cosmological parameters. In the
most favorable model, it is possible to achieve a level of 1.7% with a network
of TianQin and LISA. We find that without EM counterparts, constraints on all
other parameters need a larger number of events or more precise sky
localization of GW sources, which can be achieved by the multidetector network
or under a favorable model for massive black hole mergers. However, in the
optimistic case, where EM counterparts are available, one can obtain useful
constraints on all cosmological parameters in the Lambda-CDM cosmology,
regardless of the population model. Moreover, we can also constrain the
equation of state of the dark energy without the EM counterparts, and it is
even possible to study the evolution of EoS of the DE when the EM counterparts
are observed.Comment: 34 pages, 17 figures, update to match published versio
Equol induces apoptosis in chemoresistant ovarian cancer cells via external pathway
Polyphenolic compounds present in fruits, vegetables and grains are bioactive molecules which elicit a wide range of responses both in vivo and in vitro. The aim of this study was to investigate whether the soybean isoflavone equol could induce apoptosis in ovarian cancer cells. In this study, we evaluated molecular events associated with apoptosis induced by equol and paclitaxel (PTX) in an ovarian cancer cell line SKOV-3. To assess whether growth inhibition was due to apoptosis, flow cytometry, colorimetry experiments, immunoblot analyses through measuring DNA fragmentation, the level of TRAIL,the cleavage of poly(ADP-ribose) polymerase (PARP) and the activation of caspase-3, -8 and -9 were also performed. Additional markers of apoptosis were also measured like phosphatidylserine externalization and morphological changes. In addition, glycoprotein P (P-gp) activity in SKOV-3 ovarian cancer cell line was also estimated. The experimental results showed that apoptosis was induced by extrinsic pathway triggered by certain TNF family members. Overall results suggested that equol induces apoptosis in SKOV-3 cells via a TRAIL and caspase 8-dependent pathway whereas paclitaxel leads to smaller apoptotic events when compared to that of equol
Studies on the protective effect of total flavonoids from Cichorium glandulosum roots against carbon tetrachloride-induced liver fibrosis in rats
Purpose: To study the protective influence of total flavonoids from Cichorium glandulosum roots (TFCG) against carbon tetrachloride-mediated hepatic fibrosis in rats, and the probable mechanism of action involved.Methods: Rats with liver fibrosis were orally administered TFCG (50, 100 or 200 mg/kg) once a day for 13 weeks. Liver index and liver injury indices in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP), lactate dehydrogenase (LDH), γ-glutamyl transpeptidase (γ-GT), hydroxyproline (HYP), albumin (ALB) and malondialdehyde (MDA) were determined using electronic balance or corresponding assay kits, as appropriate. Following staining with hematoxylin and eosin and Van Gieson, histopathological changes in liver tissues were examined by light microscopy. TGF-β/Smad pathway-related protein expressions in liver tissues, viz, transforming growth factor-β1 (TGF-β1), mothers against decapentaplegic homolog 3 (Smad3), Smad7, toll-like receptor 4 (TLR4) and α-smooth muscle actin (α-SMA) were determined using immunohistochemical techniques.Results: Exposure to TFCG significantly reversed abnormal serum levels of ALT, AST, AKP, LDH, γ- GT, HYP, ALB and MDA rats with liver fibrosis to normal levels, and also decreased their liver index values (p < 0.01). Moreover, TFCG improved histopathological changes in the liver tissues of fibrotic rats, and significantly reversed abnormal TGF-β1, Smad3, Smad7, TLR4 and α-SMA protein expressions in the liver tissues of fibrotic rats to normal levels (p < 0.05 or 0.01).Conclusion: These results indicate that TFCG exerts protective effect against liver fibrosis via a mechanism related to inactivation of TGF-β/Smad pathway. Thus, TFCG may find application in liver fibrosis therapy.Keywords: Cichorium glandulosum, Flavonoids, Liver, Fibrosis, TGF-β/Smad pathwa
Spatial Interpolation of Annual Runoff in Ungauged Basins Based on the Improved Information Diffusion Model Using a Genetic Algorithm
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