Search

The Cu-LDH@X composite materials were synthesized using the in-situ self-sacrificial template method, and the acid-base bifunctional Cs/Cu-LDO@X catalysts were prepared by impregnation-calcination. The as-synthesized catalysts were characterized by XRD, N 2 adsorption-desorption, SEM, HRTEM (EDS), FTIR, XPS, NH 3 -TPD, CO 2 -TPD techniques. The catalytic performance of the catalysts was evaluated in one step by implying a fixed-bed microreactor for the side-chain alkylation of toluene with methanol to styrene. The reaction mechanisms of the side-chain alkylation on the catalysts surface were deeply investigated. The Cs/Cu-LDO@X catalysts with adjustable acid-base sites and nanolayered structures demonstrated good catalytic performance for the side-chain alkylation of toluene. The Cs/Cu-LDO@X-3 catalyst exhibited the best catalytic performance with toluene conversion is up to 6.58%, while the selectivity of side-chain alkylated products and styrene is 91.64% and 54.16% respectively. The reaction mechanism investigation indicates that methanol dehydrogenated firstly to form formaldehyde under the action of the base sites on the catalyst surface, later, the adsorbed toluene on the acid sites underwent side-chain alkylation with formaldehyde. High selectivity of produced styrene owing to the synergistic interactions of acid-base sites and layered space-confined effects of the catalytic system. [Display omitted] • Synthesis of Cu-LDH@X composite materials by self-sacrificial template method. • Cs/Cu-LDO@X catalyst prepared by impregnation-calcination for styrene production. • Controllable acid-base properties in the catalysts enhanced catalytic performance. • Layered structure was beneficial to improve styrene selectivity. • Acid-base sites and layers space-confined effects play a synergistic role. [ABSTRACT FROM AUTHOR]

Objectives: Postoperative pancreatic fistula (POPF) is a major concern after pancreatoduodenectomy (PD). We recently designed a new anastomotic method to reduce the rate of pancreatic fistula: polytetrafluoroethylene suture buttress-reinforced pancreaticojejunostomy (PBRP).Methods: An animal model and a computer simulation were used to measure the maximum stress and tensile strength of the pancreas with and without the suture buttresses. Then, a randomized controlled trial (RCT) was performed to compare the outcome of PD between patients who underwent PBRP vs traditional pancreaticojejunostomy (TP).Results: The maximum load in the animal model was significantly higher with the suture buttresses than without (5.47 ± 1.67 N vs 3.72 ± 1.36 N, p < 0.01), and in the computer simulation, the peak stress was lower with the suture buttresses than without (54.86 vs 486.8 MPa). There were no significant differences between the two groups in the overall frequency of POPF, but the rate of clinically relevant POPF was significantly lower in the PBRP group (2.8 vs 22.8%, p = 0.028). The pancreaticojejunostomy time was significantly longer in the PBRP group (19.57 ± 3.31 vs 17.17 ± 4.83 min, p = 0.018), and the PBRP group showed a shorter drainage tube retention duration (10 vs 12 days, p = 0.006) and postoperative hospital stay (13 d vs 15 d, p = 0.031).Conclusions: PBRP is a feasible and reliable procedure for preventing clinically relevant POPF. Additional multi-institution randomized trials should be conducted to confirm these results. [ABSTRACT FROM AUTHOR]

In this paper, an output feedback H ∞ controller is proposed for active suspension of an electric vehicle driven by in-wheel motors with actuator faults and time delay. The dynamic damping in-wheel motor driven system, in which the in-wheel motor is designed as a dynamic vibration absorber (DVA), is developed to improve ride quality and isolate the force transmitted to motor bearings. Furthermore, parameters of vehicle suspension and DVA are optimized based on the particle swarm optimization (PSO) to achieve better suspension performance. As some of the states such as the DVA velocity and unsprung mass velocity are difficult to measure, a robust H ∞ output feedback controller is developed to deal with the problem of active suspension control with actuator faults and time delay. The proposed controller could guarantee the system's asymptotic stability and H ∞ performance, simultaneously satisfying the performance constraints such as road holding, suspension stroke, and actuator limitation. Finally, the effectiveness of the proposed output feedback controllers is demonstrated based on the quarter vehicle suspension model under bump and random road excitations. • A dynamic damping in-wheel motor driven system is employed. • The motor and vehicle suspension parameters are optimized based on PSO method. • A robust output feedback H ∞ controller is designed for active suspension system. • Actuator faults and time delay are dealt with via the output feedback controller. [ABSTRACT FROM AUTHOR]

An efficient Co-catalyzed hydro-difluoromethylthiolation/hydro-trifluoromethylthiolation reaction of unactivated alkenes was described. Both reactions were conducted at room temperature and a variety of common functional groups such as halogen, ester, aldehyde, enolizable ketone or ester, nitro or cyano group, sulfonate and carbamate were compatible with the reaction conditions. Radical cyclization and radical inhibitor experiments suggested that the reaction proceeds through a free radical process. Image 1 [ABSTRACT FROM AUTHOR]

As a persistent and widespread toxic organic pollutant in the environment, perfluorooctane sulfonate (PFOS) has the potential to cause great harm to wildlife. In our study, the effects of PFOS on neurodevelopment gene expression, neurotransmitter content, neuronal morphology, acetylcholinesterase (AChE) activity were examined, and the potential neurotoxicity mechanisms of PFOS were also investigated in planarians, Dugesia japonica . Using quantitative real-time PCR analysis, five neurodevelopmental related genes were measured, among which, DjotxA , DjotxB , DjFoxD , and DjFoxG were found to be down-regulated, while Djnlg was found to be up-regulated, following exposure to PFOS for 10 days compared with control groups. In addition, the neurotransmitters including dopamine, serotonin, and γ-aminobutyricacid as well as the acitivity of AChE were altered by PFOS exposure. Furthermore, PFOS exposure altered brain morphology as well as smaller cephalic ganglia which displayed reduced nerve fiber density decreased brain branches compared to controls. Our results demonstrate that neurotransmission was disturbed after exposure to PFOS and that exposure to this pollutant can cause neurotoxic defects. Results from this study provide valuable information regarding the neuro- and ecological toxicity of PFOS in aquatic animals and aquatic environments. [ABSTRACT FROM AUTHOR]

[Display omitted] Subcellular localization of organelles can achieve accurate drug delivery and maximize drug efficacy. As the largest organelle in eukaryotic cells, the endoplasmic reticulum (ER) plays an important role in protein synthesis, folding, and posttranslational modification; lipid biosynthesis; and calcium homeostasis. Observing the changes in various metal ions, active substances, and the microenvironment in the ER is crucial for diagnosing and treating many diseases, including cancer. Excessive endoplasmic reticulum stress (ERS) can have a killing effect on malignant cells and can mediate cell apoptosis, proper modulation of ERS can provide new perspectives for the treatment of many diseases, including cancer. Therefore, the ER is used as a new anticancer target in cancer treatment. This review discusses ER-targeting fluorescent probes and ERS-mediated nanoanticancer strategies. [ABSTRACT FROM AUTHOR]

The content of the Si–OH group markedly affects the physical and chemical properties of MQ silicone resin (MQ) and its secondary processing products. However, current methods for the determination of the Si–OH group are still unsatisfactory due to their insensitivity and inaccuracy. Herein, an accurate analytical method has been developed for the determination of the active Si–OH group in MQ based on benzoylation and GPC–UV analysis. The UV-insensitive Si–OH group in MQ was converted to a UV-sensitive benzoyl group by the benzoylation with p -methoxy benzoyl chloride, which greatly improved its detection sensitivity. The interference of water was also excluded by the introduction of GPC separation. The effect of several derivatization parameters was investigated and optimized, and complete benzoylation of the Si–OH group in MQ was achieved under the optimized experimental parameters. Good linearity was obtained in a range of 0.425–42.5 μg/g for the content of the Si–OH group in MQ, with a correlation coefficient greater than 0.999. Reasonable reproducibility was also obtained, with the intraday RSD (N = 3) of 1.78 % and the interday RSD (3 days) of 3.98 %, respectively. This method has been successfully applied for the determination of the active Si–OH group in several commercial MQs. [ABSTRACT FROM AUTHOR]

• Thermophilic lipase was immobilized in inorganic nanoflower via biomimetic mineralization. • The immobilized enzyme showed favorable catalytic activity and stability. • The immobilized enzyme possessed excellent reusability and long-term storage stability. Thermophilic lipase QLM from Alcaligenes sp. was successfully immobilized in Cu 3 (PO 4) 2 -based inorganic hybrid nanoflower through biomimetic mineralization. The morphology, structure and element composition of immobilized enzyme were systemically characterized to elucidate the successful loading of enzyme molecules. The optimal temperature (65 °C) and pH (8.0) of immobilized enzyme were then determined by monitoring the hydrolysis of p -nitrophenyl caprylate. Moreover, compared with free enzyme, immobilized enzyme in inorganic hybrid nanoflower exhibited enhanced stability against thermal, pH and metal ions, attributing to the protective effect of nanoflower shell. Additionally, the immobilized enzyme possessed excellent reusability and long-term storage stability, with slightly decreased activity after being repeatedly used for 8 cycles or stored in water at room temperature for 4 weeks. Overall, the immobilization in inorganic hybrid nanoflower provided a facile and effective approach for the preparation of immobilized enzymes with favorable activity, stability and reusability, and thus the strategy showed great potential in developing ideal catalysts for future biocatalytic applications. [ABSTRACT FROM AUTHOR]

Perfluorooctanoic acid (PFOA) is a widely used synthetic industrial chemical which accumulates in ecosystems and organisms. Our study have investigated the neurobehavioral effects of PFOA and the alleviation effects of PFOA-induced neurotoxicity by blueberry anthocyanins (ANT) in Dugesia japonica. The planarians were exposed to PFOA and ANT for ten days. Researchs showed that exposure to PFOA affected locomotor behavior and ANT significantly alleviated the reduction in locomotion induced by PFOA. The regeneration of eyespots and auricles was suppressed by PFOA and was promoted by ANT. Following exposure to PFOA, acetylcholinesterase activity continually decreased and was unaffected in the ANT group, but was elevated after combined administration of PFOA and ANT. Oxidative DNA damage was found in planarians exposed to PFOA and was attenuated after administration of ANT by the alkaline comet assay. Concentrations of three neurotransmitters increased following exposure to PFOA and decreased after administration of ANT. Furthermore, ANT promoted and PFOA inhibited neuronal regeneration. DjotxA , DjotxB , DjFoxG , DjFoxD and Djnlg associated with neural processes were up-regulated following exposure to PFOA. Our findings indicate that PFOA is a neurotoxicant while ANT can attenuate these detrimental effects. Image 1 • PFOA led to behavioral and regeneration alterations in planarians. • PFOA decreased AChE activity and neurotransmitter contents. • PFOA caused DNA damage in planarians. • PFOA caused neural morphology and genes expression changes. • Anthocyanin exposure provided protective effects against PFOA toxicity. Anthocyanin exposure provided protective effects against PFOA toxicity. [ABSTRACT FROM AUTHOR]

MIL-101(Cr)@SiO 2 @Fe 3 O 4 magnetic catalytic supports were synthesized by the in-situ growth method, where a MIL-101(Cr) shell was deposited on the surface of the SiO 2 @Fe 3 O 4 core. A series of Au/MIL-101(Cr)@SiO 2 @Fe 3 O 4 magnetic core-shell catalysts with different Au contents were prepared and Au nanoparticles (Au NPs) were decorated on the magnetic supports by the impregnation-reduction method. The structure of the as-synthesized catalysts was characterized by XRD, FTIR, HRTEM, XPS, N 2 adsorption-desorption, NH 3 -TPD, CO 2 -TPD, and VSM, etc. The N-methylation reaction performance and recyclability performance of the catalysts were evaluated in a high-pressure microreactor. The mechanism of the N-methylation reaction had been deeply studied. The results indicated that the thickness of the MIL-101(Cr) shell was about 120 nm, and the Au NPs (~3 nm) were dispersed on the surface and/or in the pores of MIL-101(Cr). The catalytic performance for N-methylation of CO 2 and aniline/H 2 to N-methylaniline and N,N-dimethylaniline was satisfactory. Moreover, the incredible recyclability performance (external magnet) and applicability of different amine substrates were achieved. Under the optimized conditions, the 2%Au/MIL-101(Cr)@SiO 2 @Fe 3 O 4 catalyst demonstrated the best performance, the aniline conversion nearly 44.0%, the selectivity of N-methylaniline and N,N-dimethylaniline were 71.8% and 27.6%, respectively. The reaction mechanism investigation indicated that, firstly, H 2 was adsorbed and activated on the Au NPs, and CO 2 was adsorbed and activated on the O2- Lewis base sites of MIL-101(Cr) cages. Later, the activated H-atoms reacted with the activated CO 2 to generate the formic acid as an intermediate product. Finally, the formic acid reacted with the adsorbed aniline and activated on the Cr3+ Lewis acid sites to produce N-methylaniline and N,N-dimethylaniline. The enhanced selectivity of the reaction might be attributed to the core-shell architecture, high surface area, plentiful active sites, and synergistic interactions between Au NPs and acid-base sites of the MIL-101(Cr) catalyst. [Display omitted] • The magnetic Au/MIL-101(Cr)@SiO 2 @Fe 3 O 4 core-shell catalysts were prepared. • There were adjustable acid-base sites in the MIL-101(Cr) shell. • The catalysts had satisfactory performance for N-methylation of CO 2 and aniline/H 2. • H 2 was adsorbed and activated on the Au NPs sites. • CO 2 was adsorbed and activated on the O2- Lewis base sites. [ABSTRACT FROM AUTHOR]

Fluoride is an essential trace element in the human body and plays an essential role in various physiological processes. However, fluoride ion detection in vivo remains challenging due to the lack of probes that can enter the organism and emit at the near infrared region (NIR). Herein, we developed a boron-dipyrromethene (BODIPY)-based NIR probe that takes advantage of the high resolution and deep penetration of photoacoustic imaging, which can produce high NIR absorption at 803 nm in the presence of fluoride ions, resulting in a strong photoacoustic signal in the NIR region. In addition, the probe exhibits high selectivity for fluoride ions. In view of these outstanding features, the probe was then successfully applied to fluoride ion imaging in living mice, proving that a probe is a promising tool for fluoride ion detection in vitro and in vivo. [Display omitted] • A boron-dipyrromethene (BODIPY)-based NIR photoacoustic probe for fluoride ions was developed. • The F− induced cleavage of Si–O bond results in a significant redshift to 803 nm. • Imaging fluoride ions in living mice was successfully applied. • This is the first photoacoustic probe of fluoride ions in the NIR region (700–900 nm). [ABSTRACT FROM AUTHOR]

• Thermophilic lipase was immobilized in bio-based metal-organic frameworks. • The immobilized enzyme exhibited favorable catalytic activity and stability. • The immobilized enzyme could efficiently catalyze the biodiesel synthesis. Herein, thermophilic lipase QLM from Alcaligenes sp. has been successfully immobilized in bio-based metal-organic frameworks (MOFs) through biomimetic mineralization, using zinc acetate and adenine as metal ion and organic ligand, respectively. The morphology and structure of lipase@Bio-MOF was systematically characterized by scanning electron microcopy (SEM), transmission electron microcopy (TEM), powder X-ray diffraction (PXRD) and Fourier transform infrared spectra (FT-IR). The enzyme loading in immobilized enzyme was measured to be 15.9 % by thermogravimetric analysis (TGA). Further, it was demonstrated to possess favorable catalytic activity and stability under high temperature and alkaline conditions and in the presence of metal ions, using the hydrolysis of p -nitrophenyl caprylate as a model. Finally, the immobilized enzyme was successfully applied in the preparation of biodiesel through the trans-esterification of sunflower oil with methanol, obtaining a conversion of >60 % at a high oil/methanol ratio of 8:1. Meanwhile, it showed excellent recyclability during the biodiesel production, and no changes of morphology and crystal structure were observed after being used for 3 cycles. Overall, the immobilized lipase in bio-based MOFs provided an economically and environmentally viable biocatalyst for the synthesis of biodiesel. [ABSTRACT FROM AUTHOR]