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Although ultra-precision diamond milling has been widely used for free-form machining surfaces on hard and brittle materials, there has been little research on its semi-ductile machining methods. Ultra-precision diamond milling can produce high-quality microstructured surfaces by ductile machining, but the machining efficiency is low. This study proposes a semi-ductile diamond milling method by fully considering the curvature variation of the surface, microstructure geometry characteristics, and machining parameters. Firstly, we consider the kinematic characteristics of ultra-precision diamond milling, establish the semi-ductile machining model, and also establish the relationship between machining parameters and fragmentation length. Moreover, by taking into account microstructural morphological characteristics, matching the chip thickness produced by subsequent tool rotation cycles in the feed direction with the material's critical cutting depth of ductile–brittle transition and maintaining a constant tool residual height in the step direction, and using an iterative algorithm to plan the position of the tool center of rotation during cutting, the dynamically changing tool trajectory is determined. Finally, the results of the comparison experiment between the semi-ductile diamond milling method and the conventional diamond milling method demonstrate that the sinusoidal surface machined by the SDDM has a surface roughness of only 18 nm and a consistent face shape accuracy, demonstrating the high quality and high efficiency of the method in creating microstructures on hard and brittle materials. [ABSTRACT FROM AUTHOR]

Dysregulated lipid droplet accumulation has been identified as one of the main contributors to liver steatosis during nonalcoholic fatty liver disease (NAFLD). However, the underlying molecular mechanisms for excessive lipid droplet formation in the liver remain largely unknown. In the current study, hepatic E4 promoter–binding protein 4 (E4BP4) plays a critical role in promoting lipid droplet formation and liver steatosis in a high-fat diet (HFD)–induced NAFLD mouse model. Hepatic E4bp4 deficiency (E4bp4-LKO) protects mice from HFD-induced liver steatosis independently of obesity and insulin resistance. Our microarray study showed a markedly reduced expression of lipid droplet binding genes, such as Fsp27, in the liver of E4bp4-LKO mice. E4BP4 is both necessary and sufficient to activate Fsp27 expression and lipid droplet formation in primary mouse hepatocytes. Overexpression of Fsp27 increased lipid droplets and triglycerides in E4bp4-LKO primary mouse hepatocytes and restored hepatic steatosis in HFD-fed E4bp4-LKO mice. Mechanistically, E4BP4 enhances the transactivation of Fsp27 by CREBH in hepatocytes. Furthermore, E4BP4 is modified by SUMOylation, and HFD feeding induces deSUMOylation of hepatic E4BP4. SUMOylation of five lysine residues of E4BP4 is critical for the downregulation of Fsp27 and lipid droplets by cAMP signaling in hepatocytes. Taken together, this study revealed that E4BP4 drives liver steatosis in HFD-fed mice through its regulation of lipid droplet binding proteins. Our study also highlights the critical role of deSUMOylation of hepatic E4BP4 in promoting NAFLD. [ABSTRACT FROM AUTHOR]

In this research, four water-insoluble flavonoid compounds were utilized and reacted with arginine to prepare four carbonized polymer dots with good water-solubility in a hydrothermal reactor. Structural characterization demonstrated that the prepared carbonized polymer dots were classic core-shell structure. Effect of the prepared carbonized polymer dots on protein amyloid aggregation was further investigated using hen egg white lysozyme and human lysozyme as model protein in aqueous solution. All of the prepared carbonized polymer dots could retard the amyloid aggregation of hen egg white lysozyme and human lysozyme in a dose-depended manner. All measurements displayed that the inhibition ratio of luteolin-derived carbonized polymer dots (CPDs-1) was higher than that of the other three carbonized polymer dots under the same dosage. This result may be interpreted by the highest content of phenolic hydroxyl groups on the periphery. The inhibition ratio of CPDs-1 on hen egg white lysozyme and human lysozyme reached 88 % and 83 % at the concentration of 0.5 mg/mL, respectively. CPDs-1 also could disaggregate the formed mature amyloid fibrils into short aggregates. [Display omitted] • Four water-soluble flavonoid-derived carbonized polymer dots were synthesized. • All carbonized polymer dots could inhibit HEWL and HL amyloid aggregation. • Luteolin-derived carbonized polymer dots showed the highest inhibition ratio. • The inhibition ratio was greatly related to phenolic hydroxyl groups. • Luteolin-derived carbonized polymer dots also could disaggregate the formed fibrils. [ABSTRACT FROM AUTHOR]

Global crises have created unprecedented challenges for communities and economies across the world, triggering turmoil in global finance and economy. This study adopts the dynamic conditional correlation multiple generalized autoregressive conditional heteroskedasticity (DCC–MGARCH) model to explore contagion effects across financial markets in crisis. The main findings are as follows: (1) the financial crisis and COVID-19 pandemic intensified the connection between the Chinese and US stock markets in the short term; (2) the dynamic conditional correlations (DCCs) during the COVID-19 pandemic are higher than those during the 2008 financial crisis owing to the further opening of the Chinese capital market, and financial institutions' investments in the European market are higher than those in the American markets; (3) a stepwise increase is observed in the dynamic conditional correlation between the returns on the S&P 500 Index and SSEC during and after the onset of a destructive crisis; and (4) a unidirectional contagion effect exists between the Chinese market and US market, and the Hong Kong stock market contributes to the risk spillover. Effective transmission channels of external negative shocks may be investors' sentiments, financial institutions, and the RMB exchange rate in the stock markets. This study provides useful suggestions to authorities formulating financial regulations and investors diversifying risk investments. [ABSTRACT FROM AUTHOR]

The effects of Si and Cu doping on crystal structures, magnetism, and the magnetocaloric effect of EuAl 4 have been investigated. EuAl 4 , EuAl 3.35 Si 0.65 , and EuAl 3.82 Cu 0.18 single crystals grown by the Al flux method are isotypic and crystallize in BaAl 4 -type structure with space group I 4 /mmm. Compared to the pristine compound EuAl 4 , the lattice parameter a keeps almost unchanged and c decreases obviously by Si doping, while a decreases and c increases upon Cu-substitution. These irregular changes in the lattice parameters may contribute to the electronegativity difference between Si and Cu. Cu and Si doping enhances the ferromagnetic interaction, and the direction of easy magnetization changes from the ab plane to the c axis upon the Cu-substitution. Multiple-step metamagnetic transitions are still observed in EuAl 3.35 Si 0.65 as applying the magnetic field along the c axis, while EuAl 3.82 Cu 0.18 shows ferromagnetic behavior along the ab plane and c axis. As a consequence, the low-field magnetocaloric effect is significantly enhanced. The maximum magnetic entropy change under a field change of 20 kOe increases from − 8.4 J/kg K for EuAl 4 to − 12.9 J/kg K for EuAl 3.35 Si 0.65 and − 15.9 J/kg K for EuAl 3.82 Cu 0.18. The corresponding values of refrigerating capacity are 67, 140, and 147 J/kg, respectively. The remarkable magnetocaloric performances suggest that the Cu-doped EuAl 4 compound is an excellent candidate material for low-temperature magnetic refrigeration. • The doping of Si and Cu leads to the contraction of cell volume in EuAl 4 compounds. • Cu substitution enhances the ferromagnetism, and changes the direction of easy magnetization from the ab plane to c axis. • Large low-field magnetocaloric effect is acquired in Cu-doped EuAl 4 single crystal. [ABSTRACT FROM AUTHOR]

A novel polymer poly (6-O-MMAGlc) has been synthesized via free radical polymerization of monomer methyl 6-O-methacryloyl-α-D-glucoside (6-O-MMAGlc) and characterized. The influence of poly(6-O-MMAGlc) on the formation of hen egg white lysozyme (HEWL) amyloid fibril was detailly investigated, indicating that the polymer could effectively inhibit the formation of HEWL amyloid fibril. The formation kinetics of HEWL amyloid fibril with the presence of poly(6-O-MMAGlc) was measured by Thioflavin T (ThT) fluorescence method, demonstrating that poly(6-O-MMAGlc) could significantly inhibit the amyloid fibril formation of HEWL in a dose-dependent manner. The inhibitory result was furtherly illustrated by congo red (CR) binding assay, 8-anilino-1-naphthalenesulfonic acid (ANS) fluorescence assay, circular dichroism (CD) spectroscopy and transmission electron microscope (TEM). • A novel polyglucoside was synthesized. • The polyglucoside can inhibit the formation of HEWL amyloid fibrils. • The inhibitory effectivity was in a dose-dependent manner. [ABSTRACT FROM AUTHOR]

Given the high fluorescence quantum yield and modifiability of pyrene, we designed, synthesized and characterized three novel pyrene derivatives (1‐‐3) bearing electron donors and/or acceptors. All of them exhibited strong emission bands at 470 nm, 527 nm, 606 nm in toluene and slightly red‐shifted bands in the solid state due to intermolecular interactions in the densely packed state. In addition, these compounds exhibited high thermal stability with decomposition temperatures of up to 372 °C for 1, 462 °C for 2 and 429 °C for 3. Fabrication of organic light emitting diodes with 1–3 as active layers were conducted, and the devices gave multi‐color fluorescence, including cyan, chartreuse and orange light with the CIE coordinates of (0.14, 0.35), (0.38, 0.59) and (0.58, 0.41), respectively. [ABSTRACT FROM AUTHOR]

Micro lens arrays (MLAs) are widely applied in different areas to fulfill different functions. Ultra-precision diamond cutting technology can generate MLA with sub-micrometer form accuracy and nanometer surface roughness but mostly for nonferrous material. In this paper, a three-axis micro punching machine tool is developed to use diamond tool to produce MLAs on steel mold. The developed micro punching machine realizes high-feed and high-precision motions by a macro-micro composite structure. An on-site measurement system based on machine vision is designed to provide evaluation results for MLAs and compensation data for the PZT. The fabrication methodologies for MLAs are studied under the consideration of the output voltage of PZT, tool path generation, and machining parameters. Experiments are conducted to testify the machine tool and the on-site measurement system by machining of MLAs on mold steel. The experimental results show that the micro punching machine can produce MLAs on hard materials with sub-micrometer form accuracy, and the evaluation results from the on-site measurement are close to those from the white-interference profiler. [ABSTRACT FROM AUTHOR]

Abstract Gene therapy has shown promise in antitumor strategies for advanced cancer. However, efficient and safe delivery of potent therapeutic gene expressing in specific tumor tissues remains elusive, especially when there exist stromal obstacles. Here we report a non-viral gene delivery approach targeting pancreatic stellate cells (PSCs) as the transfection host in the fibroblast-enriched tumor microenvironment of pancreatic cancer. Plasmid DNA (pDNA) encapsulated in branched polyethylenemine (BPEI) was found to selectively transfect PSCs rather than pancreatic cancer cells and other fibroblast cell lines. Mechanism investigations reveal that the highly expressed fibroblast growth factor receptors (FGFRs) in PSCs facilitated the cellular uptake of polyplexes in PSCs. This delivery platform carrying gene encoding of TNF-related apoptosis-inducing ligand (TRAIL) displayed effective by-stander effect and tumor cell-selective cytotoxicity. More importantly, the therapeutic efficacy was proved in a PSC-enriched orthotopic pancreatic tumor model. Thus, this gene delivery strategy smartly converts PSCs as the microenvironment obstacle for drug delivery into the producer and reservoir of selective tumor-killing proteins. Graphical abstract Unlabelled Image [ABSTRACT FROM AUTHOR]

The potential application of curcumin was heavily limited in biomedicine because of its poor solubility in pure water. To circumvent the detracting feature, two novel water-soluble amino acid modified curcumin derivatives ( MLC and DLC ) have been synthesized through the condensation reaction between curcumin and N α -Fmoc-N ε -Boc- l -lysine. Benefiting from the enhanced solubility of 3.32 × 10 − 2 g/mL for MLC and 4.66 × 10 − 2 g/mL for DLC , the inhibition effects of the as-prepared derivatives on the amyloid fibrillation of lysozyme (HEWL) were investigated detaily in water solution. The obtained results showed that the amyloid fibrillation of HEWL was inhibited to a great extent when the concentrations of MLC and DLC reach to 20.139 mM and 49.622 mM, respectively. The fluorescence quenching upon the addition of curcumin to HEWL provide a support for static and dynamic recombination quenching process. The binding driving force was assigned to classical hydrophobic interaction between curcumin derivatives and HEWL. In addition, UV–Vis absorption and circular dichroism (CD) spectra confirmed the change of the conformation of HEWL. [ABSTRACT FROM AUTHOR]

Hypergraph is an effective method used to represent the contextual correlation within hyperspectral imagery for clustering. Nevertheless, how to discover the closely correlated samples to form hyperedges is the key issue for constructing an informative hypergraph. In this article, a new spatial-spectral locality constrained elastic net hypergraph learning model is proposed for hyperspectral image clustering (i.e. unsupervised classification). In order to utilize the spatial-spectral correlation among the pixels in hyperspectral images, first, we construct a locality-constrained dictionary by selecting K relevant pixels within a spatial neighbourhood, which activates the most correlated atoms and suppresses the uncorrelated ones. Second, each pixel is represented as a linear combination of the atoms in the dictionary under the elastic net regularization. Third, based on the obtained representations, the pixels and their most related pixels are linked as hyperedges, which can effectively capture high-order relationships among the pixels. Finally, a hypergraph Laplacian matrix is built for unsupervised learning. Experiments have been conducted on two widely used hyperspectral images, and the results show that the proposed method can achieve a superior clustering performance when compared to state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Crayfish carapace powder is a low cost natural absorbent effective for the removal of heavy metals. Its adsorption capacity was far superior to its extracts—namely, chitin and chitosan. To understand the mechanism of heavy metals removed by this material, various techniques were implemented to characterize the samples. Scanning electron microscopy and X-ray diffraction analysis showed there was metal carbonate crystal formed on the surface of carapace granules after adsorbing heavy metal ions. The ion exchange between Ca2+and M2+, chelation between M2+and chitin, protein, chemical precipitation, and physical adsorption may be the external mechanism of adsorption. [ABSTRACT FROM PUBLISHER]

A series of pyrene/phenanthrene-fused furan derivatives ( 1- 8) were synthesized by a simple condensation reaction between pyrene-4,5-diketone/phenanthrenequinone and substituted phenol/naphthol in the presence of trifluoromethanesulfonic acid in 1,2-dichlorobenzene heated at reflux. The formed compounds can emit strong blue light in organic solvents. Additionally, the self-assembly behaviors of two of the compounds ( 3 and 5) were studied through re-precipitation method and the resulting nanostructures were characterized by UV/Vis, fluorescence spectra, and field-emission scanning electron microscopy (FESEM). The findings showed that the shape and size of compounds 3 and 5 could be tuned by the ratio of THF and hexadecyl trimethyl ammonium bromide (CTAB) solution in water. [ABSTRACT FROM AUTHOR]

A porous imidazolium polymeric network was synthesized via alkylation of tetrakis-[4-(1 H -imidazole-1-yl)phenyl]methane with 1,4-bis(bromomethyl)benzene. Its complexation with palladium yielded a Pd-NHC porous polymeric network, namely Pd-pNHC. Pd-pNHC showed selective uptake of CO 2 over N 2 due to its polar surface. Pd-pNHC has a BET specific surface area of 308 m 2 g −1 and a micropore volume of 0.190 cm 3 g −1 . Pd-pNHC showed ability to absorb both hydrophilic and aromatic guests (MeOH, EtOH and benzene). Pd(II) catalytically active centers within the porous polymeric network were readily accessible to substrates as demonstrated in Suzuki–Miyaura coupling reactions. High yields were achieved in the coupling reactions of various arylbromides under mild conditions. Additionally, Pd-pNHC catalyzed the reactions in a heterogeneous way and the catalyst could be used for at least ten times without loss of activity. [ABSTRACT FROM AUTHOR]

Highlights: [•] A simple method is developed by phase separation triggered by temperature. [•] Impurities are removed through magnified solubility differences. [•] Temperature combined with ethanol-washing is studied. [•] Physicochemical properties and purity of KGM could be controlled by temperature. [ABSTRACT FROM AUTHOR]

Simple Summary: Environmental noise influences the behavioral patterns of animals. However, few quantitative studies have evaluated the effects of ship noise on wintering waterbirds in lakes. In this study, the effects of ship noise simulated by noise playback at different intensities and interference distances on the behaviors of the bean goose, a wintering waterbird species, were evaluated. Sensitivity to noise was higher in small populations than in large populations. Noises of >70 dB at distances of <100 m and >80 dB at <200 m clearly altered the flight patterns of bean geese. This study provides insight into the tolerance of endangered and protected waterbirds to environmental noise and may guide the development of strategies to minimize the impact of ship noise. Wild animals are vulnerable to environmental noise. In wetlands, wintering waterbirds are easily disturbed by ship noises; however, the behavioral changes of waterbirds in response to different levels of noise are unclear. We simulated the acoustic environment created by ship movement to investigate the effects of ship noise on foraging, vigilance, and flight behaviors of the wintering bean goose (Anser fabalis). In particular, we used a noise playback method to simulate the acoustic environment created by ship operations at various noise levels (i.e., background noise <50 dB, 60, 70, 80, 90, and 100 dB), distances from the noise (i.e., short <100 m, medium 100–200 m, and long distances 200–300 m), and noise duration (i.e., short 0–1 min, medium 2–3 min, and long 4–5 min). Results indicated that the noise intensity and interference distance had obvious influence on the bean geese behavior, but the noise duration had no effect. Smaller populations (N ≤ 30) were more sensitive to noise interference. As the noise level increased, the frequency of foraging behavior decreased and the frequencies of vigilance and flight behaviors increased, particularly above 70 dB. For noises >70 dB at short disturbance distances and >80 dB at medium disturbance distances, flight behavior increased significantly. These findings suggested that ships should keep a distance of more than 200 m from waterbirds to reduce noise interference. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel indigo derivative (1) was synthesized and characterized. [•] Single crystal analysis shows that compound 1 is a planar molecule. [•] Its positive response to fluoride ions can be directly detected by the ‘naked eyes’. [ABSTRACT FROM AUTHOR]

Highlights: [•] Aqueous CdSe/ZnS QDs were prepared using polymaleic anhydrides as capping ligand. [•] Effect of reaction temperature and time were systematically studied in the synthesis process. [•] Water-soluble QDs exhibited a good stability in physiological relevant environment. [•] The aqueous QDs were applied as biological probe to detect human embryonic stem cell. [ABSTRACT FROM AUTHOR]

Current action mechanisms for aptamer‐based therapeutics depend on occupancy‐driven pharmacology to mediate protein functions. We report a new mechanism where aptamers leverage cellular proteasomal degradation system to degrade proteins for cancer treatment. A DNA aptamer (hereinafter referred to as c‐Met‐Ap) binds to the extracellular domain of mesenchymal‐epithelial transition factor (c‐Met) and selectively induces c‐Met phosphorylation at Y1003 and Y1349. The phosphorylation of Y1003 recruits E3 ubiquitin ligase casitas B‐lineage lymphoma, causing c‐Met ubiquitination and degradation in the proteasome. Furthermore, c‐Met‐Ap can induce a decrease in the heterodimeric partner proteins of c‐Met and the downstream effector proteins in the c‐Met signal axis, effectively inhibiting tumor growth in A549 tumor‐bearing BALB/c mice. Our study uncovers a novel, actionable mechanism for aptamer therapeutics and opens a new avenue for developing highly efficient anticancer drugs. [ABSTRACT FROM AUTHOR]

Current action mechanisms for aptamer‐based therapeutics depend on occupancy‐driven pharmacology to mediate protein functions. We report a new mechanism where aptamers leverage cellular proteasomal degradation system to degrade proteins for cancer treatment. A DNA aptamer (hereinafter referred to as c‐Met‐Ap) binds to the extracellular domain of mesenchymal‐epithelial transition factor (c‐Met) and selectively induces c‐Met phosphorylation at Y1003 and Y1349. The phosphorylation of Y1003 recruits E3 ubiquitin ligase casitas B‐lineage lymphoma, causing c‐Met ubiquitination and degradation in the proteasome. Furthermore, c‐Met‐Ap can induce a decrease in the heterodimeric partner proteins of c‐Met and the downstream effector proteins in the c‐Met signal axis, effectively inhibiting tumor growth in A549 tumor‐bearing BALB/c mice. Our study uncovers a novel, actionable mechanism for aptamer therapeutics and opens a new avenue for developing highly efficient anticancer drugs. [ABSTRACT FROM AUTHOR]

Fengyun-3C (FY-3C) is a second-generation meteorological satellite of China that was launched on 23 September 2013. The on board Visible and Infrared Radiometer (VIRR) can be used to observe global sea surface temperature (SST). In this paper, the VIRR SST products are compared with MODIS SST products and buoy measurements from 2015 to 2019. The collocations of VIRR, MODIS, and buoy SST are generated separately during the day and night with the spatial window of 0.05° × 0.05°. The comparison results show that the biases of VIRR SST minus buoy SST during the day and night are −0.21 and −0.13 °C with a corresponding robust standard deviation (RSD) of 0.58 and 0.59 °C, respectively. The mean differences between VIRR and MODIS are −0.10 and 0.08 °C with RSDs of 0.53 and 0.58 °C for the daytime and nighttime, respectively. The consistency of VIRR SST accuracy from 2015 to 2019 and the dependence of VIRR SST error on SST and latitude are also investigated. [ABSTRACT FROM AUTHOR]

R4665 --> Background: As the most common chronic liver disease, non‐alcoholic fatty liver disease (NAFLD) affects 10‐30% of the general population. Characterized by excessive lipid droplet formation in hepatocytes, fatty liver may progress to nonalcoholic steatohepatitis (NASH), eventually leading to cirrhosis and liver failure. Currently, there have been no effective therapeutic or preventive measures for NAFLD. Thus, there is an urgent need to identify hepatic mediators that promote lipid droplet accumulation as well as the underlying molecular mechanisms in the liver during the pathogenesis of NAFLD. We previously reported that E4 promoter‐binding protein 4 (E4BP4) is an insulin‐induced stabilizer of the lipogenic factor SREBP‐1c and promotes the SREBP‐1c‐mediated lipogenesis in hepatocytes. Our most recent mass spectrometry data revealed that E4BP4 may undergo SUMOylation, a reversible post‐translational modification that was shown to regulate E4BP4‐dependent NK cell development. In this study, we set out to determine how hepatic E4BP4 regulates lipid droplet formation and liver steatosis a high‐fat diet‐induced NAFLD mouse model and investigate how E4BP4 SUMOylation impacts the process. Results: Compared with E4bp4flox/flox mice, E4bp4 liver‐specific KO (E4bp4‐LKO) mice exhibit decreased lipid accumulation in the liver despite similar body weight after 12 weeks of high‐fat diet feeding. Our microarray analysis showed a reduction in the expression of lipid droplet biding genes such as Cidea, Cidec (Fsp27), Plin4 in the liver of E4bp4‐LKO mice. Restoring E4bp4 expression in E4bp4‐LKO primary hepatocytes was sufficient to induce lipid droplet formation and Fsp27β expression, while overexpression of Fsp27β increased lipid droplets and triglycerides in E4bp4‐LKO primary mouse hepatocytes and promoted lipid accumulation HFD‐fed E4bp4‐LKO mice. Meanwhile, we generated an E4BP4 mutant, namely E4BP4‐5KR, which contains five lysine to arginine (5KR) substitutions in the five SUMOylation motifs. Our in vitro SUMOylation assay confirmed the SUMOylation of E4BP4‐WT but not E4BP4‐5KR mutant in the presence of E1/2, SUMO2/3, and ATP. We detected more lipid droplet formation in hepa1 cells transfected with E4bp4‐5KR vs. E4bp4‐WT. Lastly, the abundance of SUMOylated E4BP4 was reduced in the liver of high‐fat diet‐fed mice vs. regular chow‐fed mice. Conclusion: All together, our data demonstrated that E4bp4 drives lipid droplet formation and live steatosis in high‐fat diet‐fed mice likely through its regulation of lipid‐droplet binding genes. Our study also highlights the critical role of deSUMOylation of hepatic E4BP4 in promoting NAFLD and suggests that E4BP4 SUMOylation in the liver could be targeted for treating NAFLD. [ABSTRACT FROM AUTHOR]

Four novel curved polycyclic aromatic hydrocarbons 3 a, 5, 8, 15 a have been synthesized and characterized, where molecules 3 a and 15 a bear [5]carbohelicene units. X‐ray single crystal analyses indicate that compound 3 a shows offset packing arrangements of (P5)‐ and (M5)‐isomers, and 15 a has a symmetrical plane and looks like a butterfly. In comparison, 8 exhibits a slightly curved structure, in which the significant convex‐to‐convex π‐overlap with the shortest distance of 3.42 Å occurs. In addition, the effect of annulation mode of twistarenes on the physical properties, self‐assembly behaviors, and switchable photoconductivity of the as‐prepared curved aromatic compounds were further examined in a comparative manner. [ABSTRACT FROM AUTHOR]

Many proteins could aggregate into amyloid fibrils under certain conditions. However, the aggregation process and morphology of the fibrils may be significantly different because of the distinct protein structure. In this article, the hydrophilic carbon dots (Lys‐CA‐CDs) were prepared using lysine (Lys) and citric acid (CA) as reactant under the assistance of a microwave. The dissimilar modulation effect of Lys‐CA‐CDs on the aggregation process of distinct structure protein was further investigated, where bovine serum albumin (BSA) and hen egg white lysozyme (HEWL) were chosen as model proteins. All results showed that Lys‐CA‐CDs displayed the contrary influence on the aggregation process of BSA and HEWL. Lys‐CA‐CDs could induce BSA to aggregate into more wormlike fibrils and inhibit the aggregation of HEWL into hair‐like fibrils. The influence on the aggregation process of BSA may be assigned to the increased concentration of BSA around the Lys‐CA‐CDs caused by their interaction. However, inserting of Lys‐CA‐CDs into the inner structure of HEWL led to the change of protein secondary structure. The change of secondary structure further made it difficult for HEWL to aggregate into fibrils and Lys‐CA‐CDs showed the inhibition effect on HEWL aggregation. [ABSTRACT FROM AUTHOR]

The visible and infrared scanning radiometer (VIRR) onboard the Fengyun-3C (FY-3C) meteorological satellite has 11 μm and 12 μm channels, which are capable of sea surface temperature (SST) observations. This study is based on atmospheric radiative transfer modeling (RTM) by applying Bayesian cloud detection theory and optimal estimation (OE) to obtain sea surface skin temperature ( SST skin ) from VIRR in the Northwest Pacific. The inter-calibration of FY-3C/VIRR 11 μm and 12 μm brightness temperature (BT) is carried out using the Moderate Resolution Imaging Spectroradiometer (MODIS) as the reference sensor. Bayesian cloud detection and OE SST retrieval with the calibration BT data is performed to obtain SST skin . The SST skin retrievals are compared with the buoy SST with a temporal window of 1 h and a spatial window of 0.01°. The bias is −0.12 °C, and the standard deviation is 0.52 °C. Comparisons of the retrieved SST skin with the AVHRR (Advanced Very High Resolution Radiometer) SST skin from European Space Agency Sea Surface Temperature Climate Change Initiative (ESA SST CCI) project show the bias of 0.08 °C and the standard deviation of 0.55 °C. The results indicate that the VIRR SST skin are consistent with AVHRR SST skin and buoy SST. [ABSTRACT FROM AUTHOR]

Ethnopharmacological relevance Oral squamous cell carcinoma (OSCC) is one of the most common malignant tumors, seriously compromising patients' quality of life. Previous studies showed that Zengshengping (ZSP), a popular traditional Chinese medicine, has certain inhibiting effects on both oral precancerous lesions and OSCC. However, few reports underlined ZSP side effects such as liver toxicity, which limit its long-term application. Aim of the study was to evaluate the chemopreventive effect of a modified ZSPs formula on oral cancer in a hamster model. Its effect on hamster liver was also assessed. Materials and Methods The original medicine (ZSP-1) and other two formulas slightly different and called ZSP-2 and ZSP-3 were prepared ahead of time. DMBA (0.5%) was topically applied for 6 weeks to induce a premalignant lesion on hamsters' cheek pouch, then ZSP-1/2/3 were intragastrically administered for 8 weeks. Hamster treated with DMBA + each of the ZSPs represented the ZSP-1/2/3 groups, while those without ZSP-1/2/3 treatment represented the DMBA group. To assess the effect of ZSPs in the liver, intragastric administration of ZSP-1/2/3 was carried out to other groups of hamsters for 12 weeks and the blood was collected every two weeks to detect the hepatic function. Some of the hamsters were sacrificed at the end of 12 weeks, while the remaining animals were sacrificed after other 4 weeks to estimate the effect of ZSP-1/2/3 withdrawal on the liver. Results showed that tumor development in the ZSP-1/2/3 groups was less than that in DMBA group. BrdU, CD31 and COX-2 expression in the hyperplastic tissues was significantly lower in the ZSP-1/2/3 groups than that in the DMBA group. In addition, VEGF and COX-2 expression in ZSP-1/2/3 groups was lower while caspase-9 and p53 expression was higher than those in the DMBA group. Finally, PTEN expression in ZSP-1/2/3 groups was higher than that in the DMBA group. As regard the effect in the liver, ALP in the ZSP-1/2/3 groups was higher than that in the control group treated with an intragastric administration of ddH 2 O. After 4 weeks of withdrawal, the hamsters of the ZSP-3 group did not recover from the increase in ALP. Histopathology showed the presence of inflammatory lesions in each group after 12 weeks, especially in the ZSP-1/3 groups, and the number of apoptotic cells in the ZSP-3 group was higher than that in the other groups, without any recovery after withdrawal of the drug. At 12 weeks, the MDA in the ZSP-1 group was higher than that in the control group and the ZSP-2 group, but the difference disappeared after drug withdrawal because the MDA in the ZSP-1/3 groups decreased. Conclusions ZSP-2 possessed a chemopreventive effect against oral cancer by inhibiting inflammation, proliferation of tumor cells, generation of microvessels and by promoting tumor cell apoptosis. In addition, hepatotoxicity of ZSP-2, which might be related to oxidative stress injury, was reduced to some extent. Image 1 • The modified ZSPs have the chemopreventive effect on oral cancer in a hamster model. • Hepatotoxicity of original ZSP is relevant to oxidative stress injury. • Partial chemical compositions in RDB and CD contribute to original ZSP's hepatotoxicity. [ABSTRACT FROM AUTHOR]

Two novel Boc- L -isoleucine-functionalized curcumin derivatives have been synthesized and characterized, which exhibited enhanced solubility in water compared with the natural curcumin. The solubility could reach 2.12 mg/mL for the monosubstituted compound and 3.05 mg/mL for the disubstituted compound, respectively. Their anti-amyloidogenic capacity on the model protein, hen egg white lysozyme (HEWL), was examined in aqueous solution. ThT fluorescence assay showed that the operation concentration was only 0.5 mM when the inhibition ratio was above 70%. Meanwhile, the inhibitory capacity of monosubstituted curcumin derivative on the formation of HEWL amyloid fibrils was found to be superior to that of disubstituted derivative, suggesting that the phenolic hydroxyl group might contribute to the anti-amyloidogenic activity. Interaction study showed that both curcumin derivatives could bind with HEWL near tryptophan residues and form new ground-state complex before HEWL self-assemblies into amyloid fibrils and thus inhibits the formation of amyloid fibrils. Both of the two cucumin derivatives have displayed low cytotoxicity with HeLa cell. Unlabelled Image • Two water-soluble curcumin derivatives DILC/MILC were successfully synthesized. • The amyloid inhibitory activity of MILC was higher than that of DILC. • It was found that DILC/MILC could form a complex with lysozyme. • DILC/MILC displays low cytotoxicity towards HeLa cells. [ABSTRACT FROM AUTHOR]

Background: Progressive reduction of sodium intake is an attractive approach for addressing excessive salt intake, but evidence for this strategy in real practice is limited. We aimed to determine the feasibility, effectiveness, and safety of a progressive sodium intake reduction intervention in real-world setting. Methods: We randomized 48 residential elderly care facilities in China, with 1612 participants aged 55 years and older, to either progressive reduction (PR, 24 facilities) or no reduction (NR, 24 facilities) of the supply of study salt to the kitchens of these facilities for 2 years. The primary efficacy outcome was systolic blood pressure (SBP) at any scheduled follow-up visit. Secondary efficacy outcomes included diastolic blood pressure (DBP) at any scheduled follow-up visit, and major adverse cardiovascular events (comprising non-fatal stroke, non-fatal myocardial infarction, hospitalized non-fatal heart failure, or vascular death) and total mortality. The perception of food saltiness, the addition of out-of-study salt in meals, and 24-h urinary sodium excretion were used as process indicators. Results: Pre-specified analysis per randomization found no effect of the intervention on the 2-year overall mean systolic and diastolic blood pressure (SBP, DBP) and any other outcomes. However, post hoc analysis showed that the intervention effect on blood pressure varied over multiple follow-up visits (p for interaction < 0.046) and presented favorable differences at the 24-month visit (SBP = − 3.0 mmHg, 95%CI = − 5.6, − 0.5; p = 0.020; DBP = − 2.0 mmHg, 95%CI − 3.4, − 0.63; p = 0.004). The effect on 24-h sodium was non-significant (− 8.4 mmol, 95%CI = − 21.8 to 4.9, p = 0.216), though fewer participants with NR than with PR reported food tasting bland (odds ratio 0.46; 95%CI 0.29 to 0.73; p = 0.001). Reporting of bland food taste and other process measures indicated that intervention delivery and adherence were not fully achieved as designed. Conclusions: The experience of this real-world study demonstrated that achieving acceptability and sustainability of the progressive sodium intake reduction strategy among older adults was challenging, but it has shown potential for effectiveness in these and potentially other residential settings if the lessons of DECIDE-Salt are applied in further studies. Trial registration: ClinicalTrials.gov (NCT03290716). [ABSTRACT FROM AUTHOR]

• An analytical force model for diamond sculpturing of textured grooves is proposed. • The oscillations induced dynamic material removal mechanism is considered in the model. • A dynamic slip-line model is proposed to derive the shearing force. • The ploughing material removal mechanism is considered based on the indentation theory. The investigation on the cutting force for ultra-precision diamond sculpturing (UPDS) is important to understand its material removal mechanism and tool-workpiece reaction behaviors during cutting. However, few studies have focused on the cutting force model for UPDS of micro-grooves with textured surfaces. The prediction of the cutting force for UPDS is complicated due to its unique kinematics featuring oscillated servo motions, which inevitably leads to the dynamic material removal process featuring time varying plastic deformation directions. In the present study, an analytical cutting force model for UPDS of textured micro-grooves is proposed with the full consideration of the oscillations induced dynamic cutting conditions, round-edged effect as well as the shearing and ploughing mechanisms. Specifically, the nominal shearing force is derived by a dynamic slip-line model involving the time varying shear angle, stress, strain and strain rate in the deformation zone. A two-state model is adopted to describe sticking and sliding states of the chip on the tool rake face, based on which the frictional shearing force is calculated. When the depth of cut is lower than the critical chip thickness, the material is removed by the ploughing force that is of proportional relation to the tool-workpiece interference volume according to the indentation theory. Finally, the whole cutting force is obtained by discretization method, and the model is experimentally validated through sculpturing two types of textured micro-grooves with harmonic structures. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Novel furan ‐ embedded heteroarenes were synthesized by a one ‐ pot condensation reaction between pyrene ‐ 4,5 ‐ diketone/phenanthrenequinone and substituted phenol/naphthol catalyzed by triflic acid. The resulting molecules emit blue light in organic solvents. The self ‐ assembly behaviors of 11 ‐ fluoropyreno[4,5 ‐ b]benzofuran and naphtho[1,2 ‐ b]pyreno[4,5 ‐ d]furan were investigated by a re ‐ precipitation method, which indicated that the shape and size could be tuned by the ratio of THF to a solution of hexadecyl trimethyl ammonium bromide in water. For more details see the Full Paper by J. Xiao et al. on page 14791 ff. [ABSTRACT FROM AUTHOR]

Identification of geometric errors of translational axis is a key step to improve the accuracy of machine tools. However, during the procedure of measurement, installation errors of instruments are inevitable and should influence the measurement results. In order to avoid this and improve the reliability and accuracy of measurement, a novel identification measurement method is proposed. The errors of positioning and straightness of translational axis are measured by a laser interferometer in four installation positions. Twelve measured results are obtained, and then are used to identify six geometric errors of translation axis, based on the homogeneous transformation matrix and the least square method. Furthermore, an optimization method based on sensitivity analysis of the identification matrix is presented to obtain the optimum installation positions of the laser interferometer, to diminish the influence of the installation errors. Finally, simulations and experiments are conducted to validate the correctness and effectiveness of proposed method. The results indicate that the optimization identification method proposed is effective and accurate. [ABSTRACT FROM AUTHOR]

Exploration of functional materials for use in water treatment is one global requirement for protecting life and the environment. However, the state-of-the-art the materials used in oil/water separation and water harvesting still face challenges such as complicated processing steps, poor microstructure controllability and small-scale preparation. Here, a novel wire electrical discharge machining (WEDM) strategy is introduced to fabricate a functional copper mesh by cross machining both sides of the substrate, followed by a one-step low surface energy modification. The WEDM process makes the three-dimensional micro-nano structures can be well protected, and the low energy modification renders the surfaces superhydrophobic. The surfaces with micro-nano structures exhibited excellent superhydrophobicity (WCA≈158.8° and RA≈2°) and high durability towards mechanical abrasion (>100 cycles) and ultraviolet irradiation (>152° for 24 h). For various light/heavy oil/water mixtures, the separation efficiency of the meshes reached 98.1%, and the oil flux could reach 128.5 kL /(mm2·h). The superhydrophobic mesh could realize a highly efficient fog collection [12.0 L/(m2·h)], which was 390% and 830% higher than those treated by WEDM and the untreated copper plates, respectively. Therefore, we expect that the multifunctional superhydrophobic meshes may serve as a promising candidate for alleviating the water pollution and shortage. [Display omitted] [ABSTRACT FROM AUTHOR]

Fraxinellone (FRA), a major active component from Cortex Dictamni, produces hepatotoxicity via the metabolization of furan rings by CYP450. However, the mechanism underlying the hepatotoxicity of FRA remains unclear. Therefore, zebrafish larvae at 72 h post fertilization were used to evaluate the metabolic hepatotoxicity of FRA and to explore the underlying molecular mechanisms. The results showed that FRA (10–30 μM) induced liver injury and obvious alterations in the metabolomics of zebrafish larvae. FRA induces apoptosis by increasing the level of ROS and activating the JNK/P53 pathway. In addition, FRA can induce cholestasis by down-regulating bile acid transporters P-gp, Bsep, and Ntcp. The addition of the CYP3A inhibitor ketoconazole (1 μM) significantly reduced the hepatotoxicity of FRA (30 μM), which indicated that FRA induced hepatotoxicity through CYP3A metabolism. Targeted metabolomics analysis indicates the changes in amino acid levels can be combined with molecular biology to clarify the mechanism of hepatotoxicity induced by FRA, and amino acid metabolism monitoring may provide a new method for the prevention and treatment of DILI from FRA. [ABSTRACT FROM AUTHOR]

V-groove structure is extensively used for planar optical-fiber alignment, and its quality is critical to the functionality of the fiber connector. The core pitch of v-groove structure is the most important machining parameter, which determines the v-groove quality. And its machining precision is dominated by the machine tool motion precision in the z-axis direction. Six single kinematic errors derived from the multi-body system theory are the main factors affecting the accuracy of the machine tool motion in the z-axis direction. Therefore, this paper presents a single kinematic errors accurate fitting methodology for the micro v-groove machine tools. A function is fitted with a set of data using the existing fitting method and verified by another set of data measured at other testing points. Each set of test points have the same intervals, but their starting points are different from each other. The fitted function is constantly upgraded in the process of the verification. And the accurate fitted function is finally obtained by the recycling verification process. The results show that the accurate fitting method is effective and practical. [ABSTRACT FROM AUTHOR]

Investigation of an organic extract of the stems of Garcinia bracteata led to the isolation of two new flavones, named bracflavones A ( 1) and B ( 2). Their structures were elucidated by spectroscopic evidence. The compounds feature an isopropoxy group at C-3 compared with related known flavonoids isolated from the genus Garcinia. Compounds 1 and 2 were tested for their cytotoxicity. The results revealed that compound 1 showed high cytotoxicity against A549 and PC3 cell lines, and compound 2 showed high cytotoxicity against NB4, A549, SH-SY5Y, PC3, and MCF7 cell lines. [ABSTRACT FROM AUTHOR]

Although ultra-precision fly grooving (UPFG) is widely applied to fabricate micro-structured surfaces, few studies have focused on the cutting force model of UPFG. The unique kinematics of UPFG leads to the trans-scale variation of undeformed chip thickness from nanoscale to microscale, in which case the influence of material microstructure and size effect is prominent. This study proposes an analytical cutting force model for UPFG with full consideration of the kinematics, chip formation mechanism, material microstructure, material elastic recovery, size effect, and tool geometry. Specifically, by correlating micro-forming theory to crystal plastic theory, a hybrid slip-line model (HSLM) is developed to determine the flow stress in primary deformation zone, which can quantify the influence of size effect and microstructure, such as grain size, grain boundary, dislocation density, and crystal anisotropy, on flow stress. Then, the normal cutting force and frictional cutting force are estimated by analyzing the stress distribution and frictional states at tool-chip interface. The rubbing force induced by material elastic recovery is determined based on indentation theory. Finally, the models are experimentally validated by fly cutting of polycrystalline copper with different machining parameters, and it is also demonstrated that the proposed HSLM can capture the periodic transformation of cutting mechanism in UPFG from ploughing (compressive stress) to shearing (tensile stress) with tool rotation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Organic–inorganic hybrid aerogels with high micro- and mesoporosity were prepared from Al(acac)3/Cr(acac)3 subunits. [•] Heterometallic aerogels were prepared. [•] The aerogels have relatively hydrophobic pore surface. [•] The aerogels show ability to absorb various guest molecules. [Copyright &y& Elsevier]

Abstract: The geometric structures, relative stabilities, growth patterns, and electronic properties of pure and Rb2-substituted Au n +2 (n =1–10) clusters are investigated by using the density functional theory within generalized gradient approximation in conjunction with a valence electron basis set. The stable geometries with different spin multiplicities are determined. The results show that doping gold clusters with two Rb atoms dramatically affects the ground-state geometries of the pure gold clusters, the doped Rb atoms prefer locating on the surface and mirror symmetry positions, and the Au-capped Rb2Au n –1 clusters are the dominant growth pattern. The ground-state structures of Rb2Au n (n ⩾3) clusters tend to be considered as three dimensional configurations with a two dimensional (or only slightly tilted) gold subunits motif. The energetic and electronic properties of the Rb2Au n and Au n +2 (n =1–10) clusters are strongly dependent on sizes and structures. The average atomic binding energies show that the doped Rb atoms enhance the stabilities of host clusters for the larger clusters (n >5). Dramatic odd–even alternative behaviors are found in the fragmentation energies, the second-finite difference of energies, the HOMO–LUMO gaps, VIPs, and chemical hardness for both Rb2Au n and Au n +2 (n =1–10) clusters. In addition, it is found that Rb2Au6 isomer is the most stable of the Rb2Au n (n =1–10) clusters. [Copyright &y& Elsevier]

An amphiphilic oligo p-phenylene derivative (DCHO) bearing electron-donating group (-NH(CH2)2OH) and electron-withdrawing group (-CHO) has been synthesised and characterised. The sensing characteristics of this probe (DCHO) for cysteine (Cys) and homocysteine (Hcy) are studied in a mixture solution of DMSO-HEPES by UV-vis and fluorescence spectra. 1H NMR, MALDI-TOF and UV-vis titration experiments proved that thiazolidine and thiazinane derivatives were formed. The highly Cys/Hcy-selective fluorescence hypsochromic shift (>110 nm) can be observed due to the switching of intramolecular charge transfer, leading to potential fabrication of ratiometric fluorescent detection of Cys/Hcy. [ABSTRACT FROM AUTHOR]

Microstructured surfaces with subsurface fine crystallization have excellent mechanical properties. This study proposes a cooperative servo indenting (CSI) approach for accurately machining fine-crystallized microstructured surfaces on titanium alloys. Slow servo indentation is used in CSI to generate desired microstructured surfaces, in which large plastic strain is generated at the deep subsurface, resulting in subsurface dislocation concentration and grain refinement. Meanwhile, another fast servo motion (FSM) system cooperatively moves to compensate the springback errors according to the instantaneous indenting depth. To determine the compensating motions, a springback error model is proposed by considering the dynamic recrystallization (DRX), dislocation increment, indenting forces and subsurface strain-stress distribution. The proposed CSI approach and model are experimentally validated by machining different microstructured surfaces, such as hierarchical micro-grooves, micro QR codes, inverted micro-pyramid arrays, on Ti6Al4V alloys. The results show that springback errors lead to near 30% deviation between the machined microstructured surfaces and the desired ones, and the proposed CSI can efficiently reduce the springback errors from 4.26 to 0.62 µm. Through EBSD and nano-indentation analysis, it is also validated that highly increased dislocation density and DRX at the subsurface promote an increase of hardness of the microstructured surfaces. Besides, the grain size obviously reduces from 15 to 3 µm in the subsurface region at a depth of nearly 45 µm. [Display omitted] • The energy consumption mechanism in diamond cutting of titanium alloys is analytically and experimentally revealed. • The energy model fully considers spring back, temperature evolution and material microstructures. • The simulated and experimental results have a good accordance with the maximum error of 6.3%. • Minimum energy is consumed when cutting mechanism transforms from ploughing to shearing. • Flow stress increases with increasing speed due to prominent viscous drag effect. [ABSTRACT FROM AUTHOR]

• Two chiral CDs were synthesized by rapid microwave-assisted method. • BSA could aggregate into worm-like amyloid fibril after incubation at 65 ℃ for 8 h. • D-Asp-CDs exhibits more promotion effect on amyloid fibrillation than L-Asp-CDs. • Addition of L/D-Asp-CDs induced to net-work fibrils or more larger aggregates. In this study, two chiral carbon dots (CDs) were synthesized using L/D-aspartic acid as a carbon and chirality source via a rapid microwave-assisted one-step method. The prepared chiral CDs were characterized using various analysis techniques. Transmission electron microscopy images showed that the sizes of L-Asp-CDs and D-Asp-CDs were mainly distributed in the range of 2–4 and 1–3 nm, respectively. In circular dichroism spectra, the peaks at 200–220 nm for L-Asp-CDs and D-Asp-CDs were inherited from L-Asp and D-Asp acid, respectively. In addition, amidation reactions generated new chiral centers. Thioflavin T was used to show that the formation of bovine serum albumin (BSA) amyloid fibril did not involve a nucleation phase, and D-Asp-CDs exhibited a more significant promotion effect on BSA amyloid fibrillation than L-Asp-CDs. Native BSA could form worm-like amyloid fibrils after incubation at 65 °C for 8 h. However, the addition of L-Asp-CDs and D-Asp-CDs led to fibril networks and larger aggregates, respectively. The promotion effect was attributed to the high local concentration due to the absorption on the surface of CDs. The interaction between BSA and L/D-Asp-CDs was further studied, and the quenching mechanism was static quenching. The complex formed between BSA and D-Asp-CDs was more stable than that formed between BSA and L-Asp-CDs, which explains why D-Asp-CDs promoted BSA amyloid fibrillation more significantly than L-Asp-CDs. [Display omitted] [ABSTRACT FROM AUTHOR]

The number of the hyperbranched polymers in the system is investigated for the polymerization process to give the asymptotic form of the concentration of the n-mer. The polydispersity exponent is calculated, which coincides with that of the classical result. Finally, the asymptotic forms of the number, the weight and the z-average degrees of the polymerization were evaluated analytically to obtain polydispersity index, which is close to 1 as the reaction is quantitatively completed. [ABSTRACT FROM AUTHOR]

Background: Intellectual disability (ID) constitutes the most common group of neurodevelopmental disorders. Exome sequencing has enabled the discovery of genetic mutations responsible for a wide range of ID disorders. Case presentation: In this study, we reported on two male siblings, aged 4 and 2 years, with motor and mental developmental delays and mild dysmorphic facial features. To identify the genetic causes of these symptoms, we employed trio-whole exome sequencing for the proband. We found a novel hemizygous missense variant in the PAK3 gene (c.1112G > A, p.Cys371Tyr), which encodes the p21-activated kinase 3, in the proband, which inherited from mother. The younger brother also has the hemizygous variant, which was confirmed by Sanger sequencing. The variant is located in the kinase domain and was regarded as a likely pathogenic variant in this family. Conclusion: We diagnosed two male siblings with developmental delays as having a PAK3 likely pathogenic variant. This finding expands the list of PAK3 gene mutations associated with neurodevelopmental disorders and provides further details on its clinical features. [ABSTRACT FROM AUTHOR]

The rare-earth based magnetic kagome materials RMn 6 Sn 6 have attracted tremendous interest for their potential to host exotic topological quantum states. Here, we report the observation of the anomalous Hall effect in the kagome ferromagnet YbMn 6 Sn 6 single crystal. YbMn 6 Sn 6 has an easy-plane ferromagnetic structure till 2 K without magnetic ordering of the R ions. The low-temperature magnetoresistance is positive and does not exhibit a tendency to saturate up to 5 T. The magnetoresistance becomes negative with the increasing temperature. An intrinsic anomalous Hall conductivity with the value of 40.2 Ω−1·cm−1 is obtained in YbMn 6 Sn 6 , which is associated with the Berry curvature of electronic band structure in momentum space. Our results indicate that YbMn 6 Sn 6 may be an excellent platform to study the relationship between the magnetic and electronic structure and to explore novel quantum phenomenon. • The magnetic and transport properties of YbMn 6 Sn 6 single crystal have been investigated systematically. • Both positive and negative MR is observed in YbMn 6 Sn 6. • The intrinsic AHC deriving from Mn-based kagome lattice is comparable with that for DyMn 6 Sn 6. [ABSTRACT FROM AUTHOR]

A novel thermosensitive and water-soluble fluorescent polymer PNIPAM-curcumin (P2) containing curcumin unit was synthesized through one-pot method. The chemical structure and optical properties of compounds and polymer were characterized and tested. As the results turned out that P2 displayed excellent water solubility, thermosensitivity and exhibited strong fluorescence emission band in water. Moreover, P2 was further investigated by MTT assay and live cell imaging with HeLa cells. P2 did not have cytotoxicity in concentration of 200 µg · mL−1within 48 h and the intracellular fluorescence intensity enhanced with the concentration of P2 varying from 0 to 500 µg · mL−1. According to the experimental results, as a fluorescence probe, P2 synthesized does not only possess nice water solubility but also has the advantage of no cytotoxicity, and it can easily enter the cells, which indicates that it is a characteristic of high sensitivity and responsiveness. Therefore, P2 will have immense potential to be applied in biomedical fields. [ABSTRACT FROM PUBLISHER]

Curcumin is a potential natural anticancer drug with low oral bioavailability because of poor water solubility. The aqueous solubility of curcumin is enhanced by means of modification with the carbohydrate units. Polymerization of the curcumin-containing monomer with carbohydrate-containing monomer gives the water-soluble glycopolymer bearing curcumin pendant residues. The obtained copolymers (P1andP2) having desirable water solubility were well-characterized by infrared spectroscopy (IR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), UV–Vis absorption spectroscopy, and photoluminescence spectroscopy. The copolymerP2with a molar ratio of 1:6 (curcumin/carbohydrate) calculated from the proton NMR results exhibits a similar anticancer activity compared to original curcumin, which may serve as a potential chemotherapeutic agent in the field of anticancer medicine. The prepared glycopolymer (P2) bearing curcumin residues exhibit a similar anticancer activity to original curcumin. [ABSTRACT FROM PUBLISHER]

• A model is proposed to predict the deformation errors for microstructured surface generation of titanium alloys. • The model fully considers the dynamic cutting forces, material microstructure evolution, thermal-mechanical coupling effect and subsurface stress-strain distribution. • A novel cooperative servo cutting strategy is proposed for compensation of the deformation errors in a real-time and self-adaptive way. • The proposed strategy makes the error distribution more uniform and highly reduces the deformation error from 1.29 to 0.24 μm. • This study is helpful for understanding the plastic and elastic deformation mechanism for microstructured surface generation. In diamond servo cutting (DSC) of microstructured surfaces, the oscillated cutting motion inevitably cause non-uniform surface deformation errors. Although static and dynamic geometric errors for DSC have been studied, few studies focus on the prediction and compensation strategies of the surface deformation errors for microstructured surface generation. This study proposes an microstructured surface generation model of titanium alloys by considering the dynamic cutting forces, material microstructure evolution, thermal-mechanical coupling effect and subsurface stress-strain distribution. Harmonic microstructured surfaces are fabricated to characterize the non-uniform surface deformation errors as well as to validate the proposed model. The results show that the proposed model can accurately simulate the variation of surface plastic and elastic deformation errors as a function of undeformed chip thickness and cutting direction. Compared with the downslope cutting direction, the machined surface in upslope direction is subjected to greater plastic strain and plastic deformation errors even at the same depth of cut, due to cutting direction effect. To compensate surface deformation errors, a cooperative servo cutting (CSC) strategy is proposed by incorporating a self-adaptive fast tool servo into conventional servo cutting. The instantaneous compensation motion of CSC is jointly determined by the curvature radius deviation, instantaneous cutting depth and cutting direction. The experimental results show that CSC can make the error distribution more uniform, and greatly decrease the peak-to-valley surface deformation errors from 1.29 to 0.24 μm for different microstructured surfaces. [Display omitted] [ABSTRACT FROM AUTHOR]

Because of the difficulties in populating and stabilizing the high energy triplet excited states, achieving violet organic afterglow at ambient conditions is still a formidable challenge. In this work, we propose an efficient strategy to activate violet and deep-blue afterglow of high energy triplet excited state by in situ embedding of carbon dots (CDs) into cyanuric acid crystals (CA) (named CDs@CA). The formation of covalent bonds in CDs@CA were found crucial in activating the afterglow with lifetime and phosphorescence quantum yields up to 1.80 s and 39%, respectively. Furthermore, the relationship between luminescence and copolymerization (covalent bonding) of CDs@CA were explored, which provides evidence for the regularity of multiple luminescent centers. A light-stimulated response of CDs@CA was found useful for applications in advanced anti-counterfeiting. These results provide a foundation for designing highly efficient violet and deep-blue organic afterglow materials with potential applications in the fields of bioimaging, anticounterfeiting, and optoelectronic devices. [Display omitted] • The formation of covalent bonds in CDs@CA were found crucial in activating the afterglow with lifetime and phosphorescence quantum yields up to 1.80 s and 39%, respectively. • The relationships between luminescence and copolymerization in CDs@CA were explored. • CDs-based materials can display various violet and deep-blue afterglow by further modifying and replacing the matrices with sub-fluorophores, such as P O, C O, B O, or C N. • The light-stimulated response of CDs@CA is proposed for applications in advanced anti-counterfeiting. [ABSTRACT FROM AUTHOR]

C20H28BCl3F4Ru2, triclinic, P1̄ (no. 2), a = 7.7061(15) Å, b = 12.654(3) Å, c = 13.993(3) Å, α = 68.25(3)°, β = 78.71(3)°, γ = 88.89(3)°, V = 1240.8(5) Å3, Z = 2, Rgt(F) = 0.0686, wRref(F2) = 0.2017, T = 293(2) K. [ABSTRACT FROM AUTHOR]

Two new coumarins, 7-(4-hydroxyphenyl)-6H-[1, 3]dioxolo[4,5-g]chromen-6-one ( 1) and 7-(2-hydroxy-3,4-dimethoxyphenyl)-6H-[1,3]dioxolo[4,5-g]chromen-6-one ( 2), together with five known coumarins ( 3-7), were isolated from the roots and stems of flue-cured tobacco (a variety of Nicotiana tabacum L.). Their structures were elucidated by spectroscopic methods, including extensive 1D and 2D NMR techniques. Compounds 1 and 2 were tested for their anti-tobacco mosaic virus (anti-TMV) activity, and they show potential anti-TMV activity with inhibition rates of 14.5 and 31.2%, respectively. [ABSTRACT FROM AUTHOR]