Alginate oligosaccharides are associated with some beneficial health effects. Gut microbiota is one of the most recently identified factors in the development of several metabolic diseases induced by ...high-fat diet. Our objective was to evaluate how alginate oligosaccharides impact on high-fat diet‑induced features of metabolic disorders and whether this impact is related to modulations in the modulation of the gut microbiota. C57BL/6J mice were fed with chow diet, high-fat diet, or high-fat diet supplemented with alginate oligosaccharides for 10 weeks. Alginate oligosaccharide treatment improved lipid metabolism, such as reducing levels of TG and LDL-C and inhibiting expression of lipogenesis genes. Alginate oligosaccharide administration reduced the levels of fasting blood glucose and increased the levels of serum insulin. Alginate oligosaccharide treatment was found to lower the expression of markers of inflammation, including IL1
β
and CD11c. Alginate oligosaccharide treatment modulated gut microbial communities and markedly prompted the growth of
Akkermansia muciniphila
,
Lactobacillus reuteri
, and
Lactobacillus gasseri
. Additionally, alginate oligosaccharide intervention significantly increased concentrations of short-chain fatty acids, such as acetic acid, propionic acid, and butyric acid, as well as decreased levels of endotoxin. Alginate oligosaccharides exert beneficial effects via alleviating metabolic metrics induced by high-fat diet, which is associated with increase in
A. muciniphila
,
L. reuteri
, and
L. gasseri
, as well as the release of microbiota-dependent short-chain fatty acids and inhibition of endotoxin levels.
Organic upconversion is a unique process in which low-energy light (usually NIR light) is converted to high-energy light through either the two-photon absorption (TPA) mechanism or the ...triplet-triplet annihilation (TTA) mechanism. Both TPA upconversion (TPA-UC) and TTA upconversion (TTA-UC) have been actively investigated in recent years due to their intriguing applications in optics, biophotonics, and solar energy utilization. Although they show some similarity (
i.e.
, belonging to the nonlinear two-quantum process and needing focused excitation light), TPA-UC and TTA-UC are very different, such as in mechanism, characteristics involved, molecular design and potential applications. Here, we collectively reviewed these two kinds of upconversion processes and compared their respective characteristics and merits. We also present recent advances made in the areas of TPA- and TTA-UC, the remaining challenges and opportunities, with particular emphasis on molecular engineering of these two active upconversion materials.
Recent advances and remaining challenges are presented in the areas of TPA/TTA-UC, with particular emphasis on molecular engineering of these two upconversion materials.
This paper studies the convergences of several FFT-based discretization schemes that are widely applied in computational micromechanics for deriving effective coefficients, and “convergence” here ...means the limiting behaviors as spatial resolutions tending to infinity. Those schemes include Moulinec–Suquet’s scheme, Willot’s scheme and the FEM scheme. Under some reasonable assumptions, we prove that the effective coefficients obtained by those schemes all converge to the theoretical ones. Moreover, for the FEM scheme, we can present several convergence rate estimates under additional regularity assumptions.
Organofluorine compounds have shown their great value in many aspects. Moreover, allenes are also a class of important compounds. Fluorinated or fluoroalkylated allenes might provide an option as ...candidates for drug and material developments, as allenes allow a great number of valuable transformations. Herein, we report a metal-free synthesis of difluoromethylated allenes via regioselective trifunctionalization of 1,3-enynes. This method proceeds through double C-F bond formation with concomitant introduction of an amino group to the allene. Synthetic applications are conducted and preliminary mechanistic studies suggest that a two-step pathway is involved. DFT calculations revealed an unusual dibenzenesulfonimide-assisted fluorination/fluoroamination with NFSI. In addition, kinetic reaction study revealed the induction period of both major and side products to support the proposed reaction mechanism. This work offers a convenient approach for the synthesis of a range of difluoromethylated allenes and is also a rare example of trifunctionalization of 1,3-enynes.
A critical requirement for the successful recognition of multiple analytes is the acquisition of abundant sensing information. However, for this to be achieved requires massive chemical sensors or ...multiplex materials, which complicates the multianalysis. Thus, there is a need to develop a strategy for the facile and efficient recognition of multiple analytes. Herein, we explore the angle‐dependent structural colors of photonic crystals to provide abundant optical information, thereby generating a rainbow‐color chip to realize the convenient recognition of multiple analytes. By simply using a multiangle analysis method, the monophotonic crystal matrix chip can differentially enhance fluorescence signals over broad spectral ranges, thereby resulting in abundant sensing information for highly efficient multiple analysis. Twelve saccharides with similar structures, as well as saccharides in different concentrations and mixtures, were successfully discriminated.
Color vision: A photonic crystal that recognizes saccharides specifically allows abundant optical information to be obtained in the form of structural color. The use of a multiangle analysis method enables fluorescence signals in various spectral regions to be differentially enhanced. This approach enabled 12 saccharides with similar structures, as well as saccharides at different concentrations and in mixtures, to be successfully discriminated.
Here, we report on an efficient palladium/norbornene-catalyzed domino reaction of aryl halide, O-acyl hydroxylamine (R1R2N-OBz), and aromatic pinacol boronate (R-Bpin), selectively affording a series ...of biaryl tertiary amines in good to high yields with excellent functional group tolerance. This catalytic reaction provides a new opportunity for the convergent synthesis of biaryl amines from easily accessible starting materials.
A copper‐catalyzed decarboxylative alkylation of terminal alkynes under mild reaction conditions has been reported. Various alkyl diacyl peroxides were applied as the alkyl source for the formation ...of C(sp3)−C(sp) bond. A range of terminal alkynes including aryl alkynes and alkyl alkynes delivered the alkylated internal alkynes with good to high performances. Mechanism studies suggested that this reaction involves a free radical pathway.
Abstract
3D photonic crystals (PCs) have attracted extensive attention due to their unique optical properties. However, fabricating 3D PCs structure by 3D printing colloidal particles is limited by ...control of assembly under a fast-printing speed. Here, we employ continuous digital light processing (DLP) 3D printing strategy with hydrogen bonds assisted colloidal inks for fabricating well-assembled 3D PCs structures. Stable dispersion of colloidal particles inside UV-curable system induced by hydrogen bonding and suction force induced by continuous curing manner cooperatively realize the simultaneous macroscopic printing and microscopic particle assembly, which endows volumetric color property. Structural color can be well regulated by controlling the particle diameter and printing speed, through which various complex 3D structures with desired structural color distribution and optical light-guide properties are acquired. This 3D color construction approach shows great potential in customized jewelry accessories, decoration and optical device preparation, and will innovate the development of structural color.
Snow cover is a sensitive indicator of global climate change, and optical images are an important means for monitoring its spatiotemporal changes. Due to the high reflectivity, rapid change, and ...intense spatial heterogeneity of mountainous snow cover, Sentinel-2 (S2) and Landsat 8 (L8) satellite imagery with both high spatial resolution and spectral resolution have become major data sources. However, optical sensors are more susceptible to cloud cover, and the two satellite images have significant spectral differences, making it challenging to obtain snow cover beneath clouds and cloud shadows (CCSs). Based on our previously published approach for snow reconstruction on S2 images using the Google Earth Engine (GEE), this study introduces two main innovations to reconstruct snow cover: (1) combining S2 and L8 images and choosing different CCS detection methods, and (2) improving the cloud shadow detection algorithm by considering land cover types, thus further improving the mountainous-snow-monitoring ability. The Babao River Basin of the Qilian Mountains in China is chosen as the study area; 399 scenes of S2 and 35 scenes of L8 are selected to analyze the spatiotemporal variations of snow cover from September 2019 to August 2022 in GEE. The results indicate that the snow reconstruction accuracies of both images are relatively high, and the overall accuracies for S2 and L8 are 80.74% and 88.81%, respectively. According to the time-series analysis of three hydrological years, it is found that there is a marked difference in the spatial distribution of snow cover in different hydrological years within the basin, with fluctuations observed overall.
Dietary fiber has beneficial effects on obesity-related diseases and gut microbiota, contributing a key role in the interaction between dietary metabolism and host metabolism. Our objective was to ...investigate the cause of the improvement in multiple types of physiological states with seaweed
Undaria pinnatifida
treatment on high-fat diet-fed mice and to evaluate whether its consequent anti-adiposity and anti-hyperlipidemic effects are associated with gut microbiota and its metabolomics regulation.
U. pinnatifida
administration in our experiment was shown to significantly decrease high-fat diet-induced body weight gain, as well as epididymal and abdominal adiposity.
U. pinnatifida
intake also significantly reduced liver weight and serum triacylglycerol accumulation. We also found that improving effects of
U. pinnatifida
on high-fat diet-induced metabolic dysfunctions were associated with significant increase in specific bacteria, such as
Bacteroides acidifaciens
and
Bacteroides ovatus
, as well as metabolites, including short-chain fatty acids and tricarboxylic acid cycle intermediates. Our result provides a cheap dietary strategy to host metabolism improvement and obesity management.
Key points
•
U. pinnatifida improved adipose accumulation and lipid metabolism.
•
B. acidifaciens and B. ovatus contributed to the beneficial effects of U. pinnatifida.
•
SCFAs and TCA cycle intermediates were critical to the metabolic outcomes.
•
Our study provides a cheap dietary strategy for obesity management.
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