Fabrication of a nanocomposite catalyst via a novel and efficient strategy remains a challenge; Fe 3 O 4 nanoparticles anchored on graphene oxide (GO) sheet-supported metal-organic frameworks (MOFs). In this study, the physicochemical properties of the ensuing Fe 3 O 4 /Cu-BDC/GO are investigated using Fourier transform infrared spectrum, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, energy-dispersive X-ray detector, and atomic absorption spectroscopy. The salient features of the nanocomposite such as Cu-MOF, synergistic effect with GO sheets, and magnetic separation characteristics make it an excellent ternary heterostructure for aerobic oxidation of alcohols. The proposed nanocatalyst and co-catalyst 2,2,6,6-tetramethylpiperidine-N-oxyl substantially enhance the catalytic performance for the aerobic oxidation under very mild and sustainable reaction conditions. The heterogeneity of Fe 3 O 4 /Cu-BDC/GO composite catalyst is affirmed with the added advantage that the initial activity is well maintained even after seven cycles.

Melanocortin-4 receptor (MC4R) plays important roles in regulation of multiple physiological processes including energy homeostasis, reproduction, sexual function, and other functions in mammals. Recent studies suggested that teleost MC4Rs have different physiological functions and pharmacological characteristics when compared to mammalian MC4Rs. In this study, we investigated spotted sea bass (Lateolabrax maculatus) MC4R (LmMC4R) physiology and pharmacology. Spotted sea bass mc4r consisted of a 984 bp open reading frame encoding a protein of 327 amino acids. LmMC4R was homologous to those of several teleost MC4Rs and human MC4R (hMC4R). qRT-PCR and in situ hybridization revealed that mc4r transcripts were highly expressed in the brain, followed by pituitary and liver. Brain mc4r transcripts were down-regulated in long-term and short-term fasting challenges. LmMC4R was a functional receptor with lower maximal binding and higher basal activity than hMC4R. THIQ was not able to displace 125I-NDP-MSH but could affect intracellular cAMP accumulation, suggesting that it was an allosteric ligand for LmMC4R. In vitro studies with spotted sea bass brain cells indicated that mRNA levels of neuropeptide Y and Agouti-related peptide were down-regulated by α-MSH. In summary, we cloned spotted sea bass MC4R, and showed that it had different pharmacological properties compared to hMC4R, and potentially different functions.

VO 2 /PNIPAm hybrid thermochromic material has been verified as promising to improve optical performance of smart windows. However, VO 2 can be easily oxidized especially when being dispersed in the hydrogel matrix, and also the nonuniform dispersion of VO 2 in a host will worsen the material's optical performance. Herein, pure VO 2 (M)@ SiO 2 nanoparticles (NPs) were first prepared using a surfactant-free method. Then VO 2 (M)@SiO 2 /PNIPAm hybrid microgels were synthesized through suspension polymerization. The VO 2 (M)@SiO 2 NPs in the hydrogel matrix exhibited obviously improved resistance to oxidation. Monodispersed hybrid microgel with uniformly distributed VO 2 (M)@SiO 2 NPs (Sample I) was obtained. Meanwhile, compared with the best VO 2 film reported, our composite microgel (Sample III) demonstrated a 164% increase in the solar modulating ability at a relatively high average luminous transmittance (38.4%). All these remarkable features of VO 2 (M)@ SiO 2 /PNIPAm microgel synthesized in our work will help a lot in the practical application of the inorganic−organic hybrid nanothermochromic materials.

Exposure to high levels of fluoride (F^-) can result in dental fluorosis in different individuals, but the mechanism of dental fluorosis remains unclear. Autophagy is a highly conserved intracellular digestion process that degrades damaged organelles and protein aggregates. This study examined the effect of sodium fluoride (NaF) on the expression of Beclin1 and mTOR to elucidate the development mechanisms of dental fluorosis. HAT-7 cells were incubated with various concentrations of NaF, and autophagic vacuoles were studied by transmission electron microscopy. At both mRNA and protein level, expression of Beclin1, which is required for autophagosome formation and decreases the expression of mTOR, an autophagy-related complex, was increased at 1.2 mmol/l NaF compared to baseline (0 mmol/l NaF). Additionally, immunohistochemical analysis was performed on paraffin-embedded rat incisor sections to identify the expression of Beclin1 and mTOR proteins in vitro. Highly significant differences were detected compared to controls. In summary, our results demonstrate unequivocally that excessive amounts of fluoride cause autophagy of HAT-7 cells, indicating that autophagy is involved in dental fluorosis.

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Background. Dental caries is one of the most common chronic diseases observed in elderly patients. The development of preventive strategies for dental caries in elderly individuals is vital. Objective. The objective of the present study was to construct a generalized regression neural network (GRNN) prediction model for the risk assessment of dental caries among the geriatric residents of Liaoning, China. Methods. A stratified equal-capacity random sampling method was used to randomly select 1144 elderly (65-74 years) residents (gender ratio 1 : 1) of Liaoning, China. Data for the oral assessment, including caries characteristics, and questionnaire survey from each participant were collected. Multivariate logistic regression analysis was then performed to identify the independent predictors. GRNN was applied to establish a prediction model for dental caries. The accuracy of the unconditional logistic regression and the GRNN early warning model was compared. Results. A total of 1144 patients fulfilled the requirements and completed the questionnaires. The caries rate was 68.5%, and the main associated factors were toothache history, residence area, smoking, and drinking. We randomly divided the data for the 1144 participants into a training set (915 cases) and a test set (229 cases). The optimal smoothing factor was 0.7, and the area under the receiver operating characteristic curve for the GRNN model was 0.626 (95% confidence interval, 0.544 to 0.708), with a P value of 0.002. In terms of consistency, sensitivity, and specificity, the GRNN model was better than the traditional unconditional multivariate logistic regression model. Conclusion. Geriatric (65-74 years) residents of Liaoning, China, have a high rate of dental caries. Residents with a history of toothache and smoking habits are more susceptible to the disease. The GRNN early warning model is an accurate and meaningful tool for screening, early diagnosis, and treatment planning for geriatric individuals with a high risk of caries.

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