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1,4-Diazabicyclo[2.2.2]octane bis(sulfur dioxide), DABCO·SO2, or DABSO, a bench-stable colorless solid, is industrially produced by the reaction of DABCO with condensed and bubbled sulfur dioxide gas at a low temperature. However, in some cases, it could catalyze organic reactions. DABSO is mostly used as a surrogate of gaseous sulfur dioxide to react with organic substrates, including Grignard reagents, aryl or alkyl halides, boronic acids, various amines, diazonium salts, carboxylic acids, heterocycles, acrylamides, alkenes, alkynes, and β-alkynyl ketones, through one-pot protocols, annulation, or coupling reactions. Most of these synthetic reactions proceed via the formation of a sulfinate radical or anion. Using DABSO as a reagent, various simple to complex structures can be constructed, such as metal sulfinates, sulfonyl fluorides, sulfonamides, sulfonohydrazides, sulfonic esters, sulfonic thioesters, and sulfones. In this review, we want to investigate mechanistically the role of DABSO in organic synthesis.Previously, we have studied the trifluoroacetic acid (TFA)-catalyzed rearrangements of unsubstituted and alkoxy-substituted ortho-(pivaloylaminomethyl)benzaldehydes and revealed the formation of rearranged, regioisomeric aldehydes along with dimer-like products ("TFA dimers"). In the present study, related reactions of ortho-(pivaloylaminomethyl)benzaldehydes are described with the difference that boron trifluoride diethyl etherate (BF3·OEt2) is used as the catalyst. Although in these reactions the formation of the same "TFA dimers" can be observed after a couple of hours reaction time, during further stirring these are transformed into a new dimer-like keto compound ("BF3 dimer") that gradually becomes the main product. Apart from this, an oxoindene-type by-product is also formed. The new products are characterized by detailed NMR studies and two of them also by single-crystal X-ray diffraction. DFT calculations support the mechanism proposed for the transformations and explain the differences observed in the product distribution.Graphene-based nanochannels are a popular choice in emerging nanofluidics applications because of their tunable and nanometer-scale channels. In this work, molecular dynamics (MD) simulations were employed both to (i) assess the stability of dry and hydrated graphene nanochannels and (ii) elucidate the properties of water confined in these channels, using replica-scale models with 0.66-2.38 nm channel heights. The use of flexible nanochannel walls allows the nanochannel height to relax in response to the solvation forces arising from the confined fluid and the forces between the confining surfaces, without the need for application of arbitrarily high external pressures. Dry nanochannels were found to completely collapse if the initial nanochannel height was less than 2 nm, due to attractive van der Waals interactions between the confining graphene surfaces. However, the presence of water was found to prevent total nanochannel collapse, due to repulsive hydration forces opposing the attractive van der Waals force. For nanochannel heights less than ∼1.7 nm, the confining surfaces must be relaxed to obtain accurate hydration pressures and water diffusion coefficients, by ensuring commensurability between the number of confined water layers and the channel height. For very small (∼0.7 nm), hydrated channels a pressure of 231 MPa due to the van der Waals forces was obtained. In the same system, the confined water forms a mobile, liquid monolayer with a diffusion coefficient of 4.0 × 10-5 cm2 s-1, much higher than bulk liquid water. Although this finding conflicts with most classical MD simulations, which predict in-plane order and arrested dynamics, it is supported by experiments and recently published first-principles MD simulations. Classical simulations can therefore be used to predict the properties of water confined in sub-nanometre graphene channels, providing sufficiently realistic molecular models and accurate intermolecular potentials are employed.Photodynamic efficiency is strongly dependent on the generation rate of reactive oxygen species (ROS) and the tissue penetration depth. Recent advances in materials science reveal that organic molecules with room-temperature phosphorescence (RTP) can potentially serve as efficient photosensitizers owing to their limited dark cytotoxicity and abundant triplet excitons upon light irradiation. In this study, we combine RTP materials with two-photon excitation to improve the ROS generation, therapeutic precision, and tissue penetration of photodynamic therapy. We successfully prepared a novel RTP-based photosensitizer (BF2DCz) with a high photoluminescence quantum yield of 47.7 ± 3% and a remarkable intersystem crossing efficiency of ∼90.3%. By encapsulation into the bovine serum albumin (BSA) matrix, BF2DCz-BSA exhibits excellent biocompatibility, negligible dark toxicity, and superior photostability. Excitation using a femtosecond laser causes BF2DCz-BSA to efficiently generate ROS and precisely exert cell damage at the desired location.It is important to maintain the normal function of the pancreas in the prevention and intervention of type 2 diabetes mellitus (T2DM). This study was undertaken to explore the protective effects of fucoidan on the pancreas in T2DM rats induced by using a high fat diet (HFD) and low dose of streptozotocin (STZ) injection. The results showed fucoidan remarkably decreased the levels of fasting blood glucose, serum insulin and glycated serum protein, and increased the level of glucagon-like peptide-1 in T2DM rats. Also, fucoidan improved insulin sensitivity and reduced the postprandial blood glucose level. Meanwhile, fucoidan alleviated pancreas damage and improved the islet β cell function in T2DM rats. Additionally, fucoidan activated the PI3K/AKT signaling pathway and regulated glucose homeostasis, which seemed to be related to the protection of the pancreas from damage by inhibiting inflammation and endoplasmic reticulum stress in T2DM rats. Collectively, these results indicated that fucoidan had a potential protective effect on the pancreas, which enriched ideas for the use of fucoidan as a nutritional agent in the cure of T2DM.Since the first reports two decades ago, droplet-based systems have emerged as a compelling tool for microbiological and (bio)chemical science, with droplet flow providing multiple advantages over standard single-phase microfluidics such as removal of Taylor dispersion, enhanced mixing, isolation of droplet contents from surfaces, and the ability to contain and address individual cells or biomolecules. Typically, a droplet microfluidic device is designed to produce droplets with well-defined sizes and compositions that flow through the device without interacting with channel walls. Selleck U0126 Successful droplet flow is fundamentally dependent on the microfluidic device - not only its geometry but moreover how the channel surfaces interact with the fluids. Here we summarise the materials and fabrication techniques required to make microfluidic devices that deliver controlled uniform droplet flow, looking not just at physical fabrication methods, but moreover how to select and modify surfaces to yield the required surface/fluid interactions. We describe the various materials, surface modification techniques, and channel geometry approaches that can be used, and give examples of the decision process when determining which material or method to use by describing the design process for five different devices with applications ranging from field-deployable chemical analysers to water-in-water droplet creation. Finally we consider how droplet microfluidic device fabrication is changing and will change in the future, and what challenges remain to be addressed in the field.Three dimensional (3D) metal structures such as nickel (Ni) and copper (Cu) frames have long been regarded as a good host for lithium (Li) metal. However, Li deposition on different metals often causes obvious over-potential, affecting the electrode performance in lithium metal batteries. Here, a Ni-N-O interface was created by surface nitridation to the Ni micro-particles, which were made into 3D current collectors. The directly grown Ni3N created a thin and lithiophilic layer containing dense Li nucleation sites. The homogeneous distribution of amorphous Ni3N and NiO at the interface allowed for a fast transfer of both electrons and ions, and thus facilitated smooth and even plating/stripping of lithium. High cycling stability and rate capability were simultaneously achieved. The 3D Li@N-Ni anode exhibited an extremely low voltage hysteresis of ∼10 mV over 850 h in a symmetric cell. The full battery paired with LiFePO4 achieved steady cycling at 5C for 1500 cycles, with coulombic efficiency constantly higher than 99.2% and an average capacity loss of 0.027 mA h g-1 per cycle, demonstrating a rational strategy for the design and fabrication of efficient lithium anodes for practical applications.Chinese yam, as a kind of traditional "medicine and food homologous food" in Asia, could assistance to digestion, nourish the lungs and relieve cough. Some research also suggested that Chinese yam could prevention of hyperglycemia, but the specific mechanism of action was not clear. In this paper, an acidic polysaccharide (CYPB) was isolated from Chinese yam with the molecular weight of 1.55 × 102 kDa. The determination of the monosaccharide composition of CYPB with ion chromatography showed that CYPB was composed of rhamnose, glucose, arabinose, galactose, glucose, xylose and glucuronic acid with the ratio of 6  3.73  7.31  10.95  4.56  1. The structural analysis indicated that the CYPB contain 1 → 3, 1 → 4, 1 → 2, 1 → 6 and 1 → 3, 6 glycoside bonds. The experimental results of diabetic mice model induced by high-fat diet (HFD) and streptozocin (STZ) indicated that CYPB could improve clinical symptoms and alleviate the glucose tolerance damage symptoms effectively. The underlying mechanism of regulate blood glucose of CYPB may be related to improve the ability of synthesize glycogen, insulin resistance and reduce gluconeogenesis by regulating the expression of InsR, PI3K, Akt and FoxO3, GLUT4 proteins in PI3K/Akt signaling pathway in T2DM mice.With the increased aging of the population, the extension of lifespan and the improvement of healthspan have become important. Our previous studies showed that the rice bran peptide KF-8 exerts an antioxidant effect in cells and mice. In this study, we evaluated the effects of KF-8 on the healthspan and lifespan of Caenorhabditis elegans. We found that KF-8 prolonged the life of nematodes and showed no reproductive toxicity towards nematodes. In addition, KF-8 improved the motility of nematodes and resulted in an extended body length. Using hydrogen peroxide and juglone as stress inducers, we found that KF-8 improved the anti-stress ability of nematodes. In addition, KF-8 upregulated the expressions of skn-1, daf-16 and antioxidant genes. In addition, the life-prolonging effect of KF-8 was lost in skn-1 mutant strains and daf-16 mutant strains, indicating that KF-8 may exert anti-aging effects through skn-1 and daf-16.