743 research outputs found
A subduction-related metasomatically enriched mantle origin for the Luoboling and Zhongliao Cretaceous granitoids from South China: implications for magma evolution and Cu–Mo mineralization
<div><p>The Luoboling granodiorite porphyry and Zhongliao porphyritic biotite-granodiorite occur within the Zijinshan ore field in Fujian Province, southeast China. LA–ICP–MS zircon U–Pb dating yields ages of 103.1 ± 1.1 Ma (2σ, MSWD = 3.1) and 95.9 ± 0.6 Ma (2σ, MSWD = 1.2) for the Luoboling and Zhongliao intrusions, respectively. All rocks show high SiO<sub>2</sub>, K<sub>2</sub>O, and light rare earth element levels, variable CaO and Fe<sub>2</sub>O<sub>3</sub><sup>T</sup>, but low heavy rare earth element and high field strength element (Nb, Ta, Ti) concentrations. They also exhibit uniform initial <sup>87</sup>Sr/<sup>86</sup>Sr ratios (0.7064–0.7068) and ε<sub>Nd</sub>(t) values (−4.0 to −2.6), falling within the compositional field of Cretaceous basalts and mafic dikes in the Cathaysia Block. Together with their relatively high Hf isotopic ratios (ε<sub>Hf</sub>(t) = −5.8 to +0.7), these data suggest that the Luoboling and Zhongliao intrusions were derived from a subduction-enriched mantle source. We infer fractional crystallization processes involving early fractionation of clinopyroxene and olivine, and subsequent fractionation of garnet forming the Luoboling granodiorite porphyry, eventually followed by amphibole- and biotite-dominated crystallization, with minor accessory mineral contribution, producing the (younger) Zhongliao porphyritic biotite-granodiorite. Asthenospheric mantle sources may have also contributed to generating the melts as indicated by initial Pb isotopic compositions and Hf isotopic compositions. The generation of these intrusions was associated with the Pacific subduction in an extensional setting during the Cretaceous.</p></div
Nature-Inspired One-Step Green Procedure for Enhancing the Antibacterial and Antioxidant Behavior of a Chitin Film: Controlled Interfacial Assembly of Tannic Acid onto a Chitin Film
The
final goal of this study was to develop antimicrobial food-contact
materials based on a natural phenolic compound (tannic acid) and chitin,
which is the second most abundant polysaccharide on earth, using an
interfacial assembly approach. Chitin film has poor antibacterial
and antioxidant ability, which limits its application in industrial
fields such as active packaging. Therefore, in this study, a novel
one-step green procedure was applied to introduce antibacterial and
antioxidant properties into a chitin film simultaneously by incorporation
of tannic acid into the chitin film through interfacial assembly.
The antibacterial and antioxidant behavior of chitin film has been
greatly enhanced. Hydrogen bonds and hydrophobic interaction were
found to be the main driving forces for interfacial assembly. Therefore,
controlled interfacial assembly of tannic acid onto a chitin film
demonstrated a good way to develop functional materials that can be
potentially applied in industry
Additional file 2: Table S1. of The genetic variants in 3’ untranslated region of voltage-gated sodium channel alpha 1 subunit gene affect the mRNA-microRNA interactions and associate with epilepsy
Genetic variants and alleles in 3'UTR of SCN1A_v001 of male patients and controls (in *.ped file); Table S2. genetic variants and alleles in 3'UTR of SCN1A_v001 of female patients and controls (in *.ped file); Table S3. genetic variants in 3'UTR-SCN1A found in study subjects and their locations (in *.info file); Table S4. Fisher’s exact test on rare genetic variants for case/control association study; Table S5. 50 most expressed miRNA in four parts of CNS; Table S6. STarMir parameters of predicted miRNA-binding sites of 3’UTR of SCN1A gene in genotype groups; Table S7. the frequently lost and compensatory sites for the alteration in conserved sites of miRNAs binding of 3’UTR-SCN1A in genotype groups. Table S8. the conserved sites of miRNA binding in wild type 3’UTR-SCN1A. Table S9. the comparison of STarMir parameters between males and females. “S0”-“S14.txt” were the working input files for STarMir analysis. S0. wild type (reference) 3’UTR sequence; S1. male CTTTA haplotype 3’UTR sequence; S2. male CTCTA haplotype 3’UTR sequence; S3. male CCTTA haplotype 3’UTR sequence; S4. male TTTTA haplotype 3’UTR sequence; S5. female CTTAACA haplotype 3’UTR sequence; S6. female TTCAACA haplotype 3’UTR sequence; S7. female TTTAACA 3’UTR sequence; S8. female 6568_6571del 3’UTR sequence; S9. female 7338_7344del 3’UTR sequence; S10. female 7065_7066insG 3’UTR sequence; S11. 50 microRNAs expressed in human hippocampus; S12. 50 microRNAs expressed in human frontal cortex; S13. 50 microRNAs expressed in human cerebellum; S14. 50 microRNAs expressed in human midbrain. (ZIP 403 kb
Review of Alkali-Based Pretreatment To Enhance Enzymatic Saccharification for Lignocellulosic Biomass Conversion
Lignocelluloses
have been the focus of much attention, because
of their conversion to fermentable sugars for cellulosic ethanol production,
both from the viewpoint of energy and the environment. Pretreatment
plays a crucial rule in biomass conversion, to overcome the chemical
and structural difficulties, which have evolved in lignocelluloses,
and to produce a cost-effective fermentable sugar via enzymatic saccharification.
Among the developed pretreatment approaches, alkali-based pretreatment
technology, which can utilize the equipment and chemical recovery
system in the pulping industry, has been considered one of the most
promising pretreatment methods, mainly because of its high efficiency
in delignification and high final total sugar yields. This paper reviews
the classification, mechanism, advantages, disadvantages, and the
progress of alkali-based pretreatment technologies, in order to better
understand the fundamental principles of alkali-based pretreatments.
This is of vital importance for the process improvement and commercial
production of alkali-based pretreatment for producing cellulosic ethanol
Pretreatment of Corn Stover with the Modified Hydrotropic Method To Enhance Enzymatic Hydrolysis
Hydrotropic pretreatment using sodium
xylene sulfonate (SXS) could
remove lignin and xylan from corn stover to enhance enzymatic saccharification.
Peracetic acid (PAA) treatment prior to the hydrotropic process [so-called
modified hydrotropic pretreatment (MHP)] could double the delignification
efficiency and remarkably increase glucan conversion. After pretreatment,
samples were treated by PFI refining for comparison. With the supplement
of PFI refining before enzymatic hydrolysis of the MHP-treated corn
stover, 87.6% of the glucan yield could be achieved and the corresponding
xylan yield was 43.7%. In addition, the pretreated corn stover was
analyzed by Fourier transform infrared spectroscopy (FTIR), X-ray
diffractometer (XRD), and scanning electron microscopy (SEM). The
lignin precipitate from the spend liquor was also investigated by
FTIR. The cleavage of the lignin structure could be observed from
FTIR results. The crystallinity index (CrI) of corn stover after MHP
was increased according to XRD analysis, while the reduction of total
CrI of cellulose between pretreatment samples was analyzed by FTIR.
SEM analysis demonstrated that PAA treatment affected the morphology
of corn stover fiber by generating pores and allowing for better contact
of the enzyme to polysaccharides
Synthesis of Cinnolines and Cinnolinium Salt Derivatives by Rh(III)-Catalyzed Cascade Oxidative Coupling/Cyclization Reactions
A novel method for the synthesis
of cinnolines and cinnolinium
salt derivatives via Rh(III)-catalyzed cascade oxidative coupling/cyclization
reaction from Boc-arylhydrazines and alkynes has been developed. The
reactions have a broad substrate scope and high stereoselectivity
with readily available starting materials and provides an efficient
synthetic route for this kind of compounds. A catalytically competent
five-membered rhodacycle has been isolated, thus revealing a key intermediate
in the catalytic cycle
Least-squares fits of velocity distribution function to measured data.
<p>Least-squares fits of velocity distribution function to measured data.</p
MicroRNA-153 Inhibits Osteosarcoma Cells Proliferation and Invasion by Targeting TGF-β2
<div><p>Increasing evidence indicates that microRNAs (miRNAs), a class of small noncoding RNAs, participate in almost every step of cellular processes. MiRNAs are aberrantly expressed in human cancers and contribute to cancer development and progression. Study of miRNAs may provide a new clue for understanding the mechanism of carcinogenesis and a new tool for cancer treatment. In the present study, miR-153 was downregulated in human osteosarcoma tissues and cell lines. Introduction of miR-153 mimics into the MG-63 cells inhibited cell proliferation and invasion. Our results further revealed that transforming growth factor beta 2 (TGF-β2) was negatively regulated by miR-153. Furthermore, overexpression of miR-153 decreased p-SMAD2, p-SMAD3, epidermal growth factor receptor (EGFR) and insulin-like growth factor binding protein-3 (IGFBP-3) expressions, which were the downstream signaling molecules of TGF-β. Furthermore, miRNA-153 suppressed TGF-β-mediated MG-63 proliferation and migration. Therefore, our results suggest that miR-153 may act as a tumor suppressor in osteosarcoma through targeting TGF-β2.</p></div
Evaluation of Intestinal Drug Absorption and Interaction Using Quadruple Single-Pass Intestinal Perfusion Coupled with Mass Spectrometry Imaging
Visualization and characterization
of the intestinal
membrane transporter-mediated
drug absorption and interaction are challenging due to the complex
physical and chemical environment. In this work, an integrated strategy
was developed for in situ visualization and assessment of the drug
absorption and interaction in rat intestines using quadruple single-pass
intestinal perfusion (Q-SPIP) technique coupled with matrix-assisted
laser desorption ionization mass spectrometry imaging (MALDI MSI).
Compared with the traditional SPIP only available for perfusion of
one single intestinal segment, the Q-SPIP model can simultaneously
perfuse four individual segments of each rat intestine (duodenum,
jejunum, ileum, and colon), enabling to obtain rich data from one
rat. Subsequently, the drug distribution and absorption in rat intestinal
tissue were accurately visualized by using an optimized MALDI MSI
approach. The utility and versatility of this strategy were demonstrated
via the examination of P-glycoprotein (P-gp)-mediated intestinal absorption
of berberine (BBR) and its combination with natural products possessing
inhibitory potency against P-gp. The change in the spatial distribution
of BBR was resolved, and MALDI results showed that the signal intensity
of BBR in defined regions was enhanced following coperfusion with
P-gp inhibitors. However, enhanced absorption of BBR after coperfusion
with the P-gp inhibitor was not observed in the ulcerative colitis
rat model, which may be due to the damage to the intestinal barrier.
This study exemplifies the availability and utility of Q-SPIP coupled
with MALDI MSI in the examination of transporter-mediated intestinal
drug absorption and interaction for fundamental inquiries into the
preclinical prediction of oral absorption and drug interaction potential
Comparison of one-dimensional velocity distribution at 70% D.
<p>Comparison of one-dimensional velocity distribution at 70% D.</p
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