Facile Synthesis of Enzyme-Embedded Metal–Organic Frameworks for Size-Selective Biocatalysis in Organic Solvent

In situ immobilization of enzyme into metal–organic frameworks (MOFs) is performed through a one-step and facile method. Candida antarctica lipase B (CalB) is directly embedded in zeolitic imidazolate framework (ZIF)-8 by simply mixing an aqueous solution of 2-methylimidazole and zinc nitrate hexahydrate [Zn(NO3)2⋅6H2O] containing CalB at room temperature. Due to the intrinsic micropores of ZIF-8, the obtained CalB@ZIF composite is successfully applied in size-selective transesterification reaction in organic solvent. CalB@ZIF not only shows much higher catalytic activity but also exhibits higher thermal stability than free CalB. Besides, the robust ZIF-8 shell also offers the hybrid composites excellent reusability.</p

Surface-functionalized mesoporous nanoparticles as heterogeneous supports to transfer bifunctional catalysts into organic solvents for tandem catalysis

The combination of chemo- and biocatalysts offers a powerful platform to address synthetic challenges in chemistry, particularly in synthetic cascades. However, transferring both catalysts into organic solvents remains technically difficult because of the enzyme inactivation and catalyst precipitation. Herein, we designed a facile approach using functionalized mesoporous silica nanoparticles (MSN) to transfer chemo- and biocatalysts into a variety of organic solvents. As a proof-of-concept, two distinct catalysts, palladium nanoparticles (Pd NPs) and Candida antarctica lipase B (CalB), were stepwise loaded into separate locations of the mesoporous structure, which not only provided catalysts with heterogeneous supports for the recycling but also avoided their mutual inactivation. Moreover, mesoporous particles were hydrophobized by surface alkylation, resulting in a tailor-made particle hydrophobicity, which allowed bifunctional catalysts to be dispersed in eight organic solvents. Eventually, these attractive material properties provided the MSN-based bifunctional catalysts with remarkable catalytic performance for cascade reaction synthesizing benzyl hexanoate in toluene. With a broader perspective, the success of this study opens new avenues in the field of multifunctional catalysts where a plethora of other chemo- and biocatalysts can be incorporated into surface-functionalized materials ranging from soft matters to porous networks for synthetic purposes in organic solvents

A094: The Impact of Aerobic Exercise Combined with Intermittent Fasting on Alleviating Chronic Inflammation in Obesity

Research Aim: This study utilized aerobic exercise and intermittent fasting as intervention strategies to investigate their effects on the polarization of visceral fat macrophages and the amelioration of chronic fat inflammation in rats with obesity. Research Methods: Sixty male Sprague Dawley (SD) rats, aged 3 weeks, were randomly assigned to either a normal diet group (ND) or a high-fat diet group (HFD). Following a 12-week intervention period, the groups were further subdivided into the normal diet control group (ND), high-fat diet sedentary group (HC), high-fat diet intermittent fasting group (IF), high-fat diet aerobic exercise group (HE), and aerobic exercise combined intermittent fasting group (HIE). The aerobic exercise group underwent 10 weeks of medium-intensity training at 65% of their VO2max. The fasting group adhered to a 5:2 pattern, involving a 24-hour fasting period every Wednesday and Saturday commencing at 6 pm. During post-intervention, epididymal fat samples were collected, and wet weights were recorded. HE staining facilitated the observation of fat histopathology, while immunofluorescence staining was employed to identify the expression and localization of macrophage polarization-related proteins CD86 and CD206. Protein expression levels of IL-6, IL-10, TNF-α, iNOS, and Arg-1 in adipose tissue were determined through Western blot analysis. Research Results: 1) In comparison to the NC group, the HC group exhibited a significant increase in epididymal adipose tissue weight and adipocyte surface area. 2) Following a 10-week intervention, the epididymal adipose tissue weight and adipocyte surface area in the HE, IF, and HIF groups showed a significant decrease when compared to the HC group. Notably, the HIF group demonstrated a more pronounced reduction. 3) Furthermore, in comparison to the HC group, the HIF group displayed a notable decrease in inflammation cells with a corona-like structure infiltrating the stroma of adipocytes. The protein levels of IL-6 and TNF-α significantly decreased, while the IL-10 protein level exhibited a significant increase. Moreover, the expression of CD86 and iNOS showed a significant decrease, whereas CD206 and Arg-1 expression exhibited a significant increase. Conclusion: High-fat diet induces an increase in M1 polarization and a decrease in M2 polarization in rat adipose tissue, triggering the onset of chronic inflammation. Following a ten-week intervention, moderate-intensity aerobic exercise combined with intermittent fasting proves was more effective in ameliorating chronic inflammation in the adipose tissue of rats with obesity

A132: Effect of Intermittent Fasting Combined with Aerobic Exercise on Lipid Deposition in Obese Rats

Goal: With the improvement of living standards, people\u27s diets tend to be more and more high-fat, and long-term high-fat diets may lead to obesity and other chronic health problems. Nearly 80% of obese patients are accompanied by varying degrees of hepatic steatosis, so there is an urgent need to seek a safe and effective treatment of obesity and lipid deposition. Methods: In this study, 3-week-old Sprague-Dawley rats were divided into normal control group (NC), high-fat group: control group (HC), light fasting group (HI), exercise group (HE), light fasting plus exercise group (HIE), and light fasting, and aerobic exercise were used as intervention methods for 10 weeks. Catabolic protein effects were investigated to explore the effects of both on hepatic lipid deposition, and the experimental data were statistically analyzed using SPSS 25.0, with one-way or two-way ANOVA tests to be used, and graphs were made using GraphPad Prism 8.0. Findings: (1) Weight was significantly higher in the HC group compared to the NC group (p \u3c 0.01). Compared with the HC group, the intervention group had lower body weight (P \u3c 0.05), with the HIE group having a greater reduction in body weight. (2) The results of HE and oil red staining after 10 weeks of intervention showed that the liver structure and histological morphology of high-fat rats underwent significant improvement (P \u3c 0.05), and the effect was more significant in the HIE group. (3) Compared with the NC group, serum TG, TC, LDL, AST, ALT were elevated (P \u3c 0.05) and HDL was reduced (P \u3c 0.05) in the HC group; compared with the HC group, TG, TC, LDL, AST, ALT were reduced, and HDL was elevated (P \u3c 0.05) in the intervention group. (4) Compared with the NC group, the expression of p-AMPK/AMPK, p-ACC/ACC, and CPT1 was significantly reduced in the liver tissues of mice in the HC group (P \u3c 0.01). The expression of p-AMPK/AMPK, p-ACC/ACC, and CPT1 was elevated in the liver tissues of the intervention group compared with the HC group (P \u3c 0.05). Discussion: The present study confirmed that the effect of light fasting plus exercise on the improvement of lipid deposition was better than that of one alone, which provided a new idea and direction for the improvement of obesity and lipid deposition; however, this study did not go into depth on the mechanism at the molecular level, which needs to be continued to be explored

Bidirectional Graph Reasoning Network for Panoptic Segmentation

Recent researches on panoptic segmentation resort to a single end-to-end network to combine the tasks of instance segmentation and semantic segmentation. However, prior models only unified the two related tasks at the architectural level via a multi-branch scheme or revealed the underlying correlation between them by unidirectional feature fusion, which disregards the explicit semantic and co-occurrence relations among objects and background. Inspired by the fact that context information is critical to recognize and localize the objects, and inclusive object details are significant to parse the background scene, we thus investigate on explicitly modeling the correlations between object and background to achieve a holistic understanding of an image in the panoptic segmentation task. We introduce a Bidirectional Graph Reasoning Network (BGRNet), which incorporates graph structure into the conventional panoptic segmentation network to mine the intra-modular and intermodular relations within and between foreground things and background stuff classes. In particular, BGRNet first constructs image-specific graphs in both instance and semantic segmentation branches that enable flexible reasoning at the proposal level and class level, respectively. To establish the correlations between separate branches and fully leverage the complementary relations between things and stuff, we propose a Bidirectional Graph Connection Module to diffuse information across branches in a learnable fashion. Experimental results demonstrate the superiority of our BGRNet that achieves the new state-of-the-art performance on challenging COCO and ADE20K panoptic segmentation benchmarks.Comment: CVPR202

Heterogeneous Metal–Organic-Framework-Based Biohybrid Catalysts for Cascade Reactions in Organic Solvent

In cooperative catalysis, the combination of chemo- and biocatalysts to perform one-pot reactions is a powerful tool for the improvement of chemical synthesis. Herein, UiO-66-NH2 was employed to stepwise immobilize Pd nanoparticles (NPs) and Candida antarctica lipase B (CalB) for the fabrication of biohybrid catalysts for cascade reactions. Distinct from traditional materials, UiO-66-NH2 has a robust but tunable structure that can be utilized with a ligand exchange approach to adjust its hydrophobicity, resulting in excellent catalyst dispersity in diverse reaction media. These attractive properties contribute to the formation of MOF-based biohybrid catalysts with high activity and selectivity in the synthesis of benzyl hexanoate from benzaldehyde and ethyl hexanoate. With this proof-of-concept, we reasonably expect that future tailor-made MOFs can combine other catalysts, ranging from chemical to biological catalysts for applications in industry.</p

Enzymes Immobilized on Carbon Nitride (C₃N₄) Cooperating with Metal Nanoparticles for Cascade Catalysis

The exploration of effective platforms for immobilizing chemo- and biocatalysts to develop biohybrid catalysts is an attractive subject of practical interest. In this work, carbon nitride (C3N4) is used for the first time as a platform for the immobilization of metal catalyst (Pd nanoparticles) and biocatalyst (Candida antarctica lipase B, CalB) in a facile manner to prepare biohybrid catalyst. The optimal biohybrid catalyst inherits the intrinsic performance of both Pd nanoparticles and CalB, and shows high activity in the one-pot cascade reaction converting benzaldehyde to benzyl hexanoate at room temperature. With this proof of concept, it is expected that C3N4 can be utilized for immobilizing more types of chemo- and biocatalysts for perspective applications.</p

Salinity appears to be the main factor shaping spatial COI diversity of Corbicula lineages within the Chinese Yangtze River Basin

info:eu-repo/semantics/publishe

Unveiling precipitation behavior in Mg-Y based alloys

Mg-Y based alloys exhibit a promising combination of strength and deformability through tuning precipitation and solute strengthening mechanisms and tailoring the activity of non-basal dislocations. Understanding the precipitation sequence of Mg-Y based alloys and its dependence on Yttrium concentration in the matrix will provide a guideline for fine tuning structure, morphology and distribution of precipitates in Mg-Y based alloys. In this paper, we explore the precipitation behaviors of Mg-11Y (wt%) and Mg-11Y-1Al (wt%) alloys using aberration-corrected scanning transmission electron microscopy, and rationalize the experimental observations based on first-principles density functional theory calculations. The precipitation sequence during ageing at 225 °C is identified to be SSSS → clusters/G.P. Zones →β′ (Mg7Y) → β′′/βt′′ (Mg3Y). A novel βt′′ phase forms through in-situ transformation from the β′ phase, which shares the same Mg3Y composition with D019-β′′ phase and exhibits the same cbco-structure as β′ phase in Mg-Y based alloys