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Water-soluble fluorescent silver nanoclusters (Ag NCs) were prepared with the assistance of commercially available polyinosinic acid (PI) or polycytidylic acid (PC). The fluorescence of the Ag NCs is effectively quenched by trace mercury(II) ions, which can be applied for their detection. The response of the Ag NCs prepared with PI to Hg(II) ion is linear in the Hg(II) concentration range from 0.05 to 1.0 μM (R = 0.9873), and from 0.5 to 10 μM of Hg(II) (R = 0.9971) for Ag NCs prepared with PC. The detection limits are 3.0 nM and 9.0 nM (at an S/N of 3), respectively. The method is simple, sensitive and fairly selective. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Highlights: [•] Well-defined urchin-like Au arrays were facilely prepared by one-step electrodeposition. [•] Iron(III) ions serve as catalysts and growth directing agents. [•] This approach is simple, controllable and convenient, without any template, seed or surfactant. [•] The Au nanocrystals display high electrocatalytic activity toward the oxidation of ethylene glycol and glycerol. [ABSTRACT FROM AUTHOR]

The quantitative analysis of the degree of knowledge granularity poses theoretical challenges for the development of granular computing. Information-theoretic measures have been proposed to address this problem, which exhibit usefulness in complete information systems. However, mathematical analysis of relationships between these information-theoretic measures and knowledge granularity has not been done. In this paper, after introducing Shannon's entropy and mutual information into complete information systems, we prove, for the first time, that these information-theoretic measures decrease monotonously as partition becomes coarser under complete information systems. Moreover, we illustrate that their inverse relationships do not hold generally and present an additional condition under which the inverse relationships are valid. By generalizing Shannon's entropy to incomplete information systems, we further discuss the relationship between the generalized Shannon's entropy (termed as rough information entropy) and knowledge granularity based on covering generalized rough sets. We find that in incomplete information systems, the rough information entropy varies nonmonotonously as covering becomes coarser. An illustrative example is given to verify the above observation result. [ABSTRACT FROM AUTHOR]

Iodine efficiently catalyzes the one-pot, three-component reaction of aryl aldehyde, 2-naphthol, and cyclic 1,3-dicarbonyl compound under solvent-free conventional heating conditions to afford the corresponding 12-aryl-8,9,10,12-tetrahydro-benzo[a]xanthen-11-one derivatives. The present approach offers several advantages such as shorter reaction times, good yields, low cost, and mild reaction conditions. [ABSTRACT FROM AUTHOR]

Noncoding RNAs have been found to play important roles in DNA damage repair, whereas the participation of circRNA remains undisclosed. Here, we characterized ciRS-7, a circRNA containing over 70 putative miR-7-binding sites, as an enhancer of miRISC condensation and DNA repair. Both in vivo and in vitro experiments confirmed the condensation of TNRC6B and AGO2, two core protein components of human miRISC. Moreover, overexpressing ciRS-7 largely increased the condensate number of TNRC6B and AGO2 in cells, while silencing ciRS-7 reduced it. Additionally, miR-7 overexpression also promoted miRISC condensation. Consistent with the previous report that AGO2 participated in RAD51-mediated DNA damage repair, the overexpression of ciRS-7 significantly promoted irradiation-induced DNA damage repair by enhancing RAD51 recruitment. Our results uncover a new role of circRNA in liquid-liquid phase separation and provide new insight into the regulatory mechanism of ciRS-7 on miRISC function and DNA repair. [ABSTRACT FROM AUTHOR]

Since the global outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a symptom of the onset of SARS-CoV-2, olfactory dysfunction (OD), has attracted tremendous attention. OD is not only a negative factor for quality of life but also an independent hazard and early biomarker for various diseases, such as Parkinson's and Huntington's diseases. Therefore, early identification and treatment of OD in patients are critical. Many etiological factors are responsible for OD based on current opinions. Sniffin'Sticks are recommended to identify the initial position (central or peripheral) for OD when treating patients clinically. It is worth emphasizing that the olfactory region in nasal cavity is recognized as the primary and critical olfactory receptor. Many nasal diseases, such as those with traumatic, obstructive and inflammatory causes, can lead to OD. The key question is no refined diagnosis or treatment strategy for nasogenic OD currently. This study summarizes the differences in medical history, symptoms, auxiliary examination, treatment and prognosis of different types of nasogenic OD by analyzing the current studies. We propose using olfactory training after 4–6 weeks of initial treatment for nasogenic OD patients with no significant improvement in olfaction. We hope that our research can provide valuable clinical guidance by systematically summarizing the clinical characteristics of nasogenic OD. [ABSTRACT FROM AUTHOR]

Eleven previously undescribed limonoids, trichisins A-K, including eight structural analogues A-H of trijugin and three H-J mexicanolide derivatives, together with two known mexicanolide derivatives were isolated from the fruits of Heynea trijuga Roxb. ex Sims. The structure determination was based on extensive physical data analyses (NMR, MS), and their basic skeletons and the absolute configurations of trichisins A, B, E, K and trichiconnarone A were assigned via X-ray crystallographic analysis (Cu K α radiation). The hemiketal motifs in trijugins A, B, and E-G are rare in limonoids. Bioactivity screenings suggested that the trijugin H and mexicanolide-type trichiconnarones A and B limonoids were effective in reversing resistance in MCF-7/DOX cells at a nontoxic concentration of 50 μM with IC 50 values of 12.45, 10.86, and 14.96 μM, respectively. [ABSTRACT FROM AUTHOR]

This paper proposes a novel method for 2D-to-3D video conversion, based on boundary information to automatically generate the depth map. First, we use the Gaussian model to detect foreground objects and then separate the foreground and background. Second, we employ the superpixel algorithm to find the edge information. According to the superpixels, we will assign corresponding hierarchical depth value to initial depth map. From the result of depth value assignment, we detect the edges by Sobel edge detection with two thresholds to strengthen edge information. To identify the boundary pixels, we use a thinning algorithm to modify edge detection. Following these results, we assign the depth value of foreground to refine it. We use four kinds of scanning path for the entire image to create a more accurate depth map. After that, we have the final depth map. Finally, we utilize depth image-based rendering (DIBR) to synthesize left and right view images. After combining the depth map and the original 2D video, a vivid 3D video is produced. [ABSTRACT FROM AUTHOR]

Abstract: Single crystalline flower-like Bi2S3 nanostructures were successfully synthesized via a simple, facile and green hydrothermal method, with the assistance of D-penicillamine. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), and found their morphologies mainly depend on the ratios of Bi3+ to D-penicillamine, as well as the reaction temperature and time. And the possible growth mechanism has been discussed in some detail. In addition, the as-prepared Bi2S3 nanoflowers show good hydrogen storage ability. This strategy can be potentially expanded to prepare other metal chalcogenides materials. [Copyright &y& Elsevier]

Abstract: Enzymatic modification of starch was conducted by lipase-coupling esterification with octenyl succinic anhydride (OSA). Parameters affecting the esterification were systematically studied. Products were characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction, differential scanning calorimetry (DSC) and viscosity analysis (VA). Optimum condition for lipase-coupling OSA starch preparation was as follows: starch pretreatment at 65°C for 15min, starch concentration 35%, amount of lipase and OSA, 0.6% and 3%, reaction pH, temperature and time, 8.0, 40°C and 30min respectively, which resulted in 0.0195 of the degree of substitution and 84.05±2.07% of the reaction efficiency. FT-IR spectroscopy confirmed the formation of OSA starch. SEM and X-ray diffraction showed apparent surface change, but no crystalline change. DSC and VA results indicated the synthesized OSA starch gelatinized rapidly with high viscosity. Attractively, reaction time drastically reduced to 30min, showing vast potential for scale production of OSA starch. [Copyright &y& Elsevier]

Shape and size control of gold (Au) nanocrystals plays important roles in their catalytic and optical properties. Hierarchical Au nanodendrites were directly electrodeposited on a glassy carbon electrode (GCE) using l-arginine as a growth-directing agent, while there is no seed, template, or surfactant involved. It was found that the experimental conditions such as the applied potentials, concentrations of HAuCl and l-arginine, and deposition time were essential to the final morphology of the Au deposits. The as-synthesized Au nanocrystals displayed enhanced electrocatalytic activity and improved stability for ethylene glycol (EG) oxidation in acidic media as compared to Au nanoparticles. [ABSTRACT FROM AUTHOR]

We have developed a simple, sensitive and selective colorimetric method for the detection of cadmium(II) (Cd) using gold nanoparticles modified with 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole. Organic solvents or additives are not required. It is found that Cd induces the aggregation of the modified Au-NPs via chelation, leading to a color change from red to blue. This change can be seen with bare eyes, and monitored by UV-vis spectroscopy, transmission electron microscopy and dynamic light scattering. The detection limit is 30 nM (at a signal-to-noise ratio of 3). The new approach was successfully applied to the detection of Cd in spiked samples of tap water and lake water, and the results agree well with those obtained by flame atomic absorption spectroscopy. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Background: Nimotuzumab is a humanized IgG1 monoclonal antibody specifically targeting EGFR. In this study, we aimed to investigate the molecular mechanisms of nimotuzumab in its effects of enhancing cancer cell radiosensitivity. Principal Finding: Lung cancer A549 cells and breast cancer MCF-7 cells were pretreated with or without nimotuzumab for 24 h before radiation to perform the clonogenic survival assay and to analyze the cell apoptosis by flow ctyometry. γ-H2AX foci were detected by confocal microscopy to assess the effect of nimotuzumab on radiation induced DNA repair. EGFR activation was examined and the levels of DNA damage repair related proteins in A549 cells at different time point and at varying doses exposure after nimotuzumab and radiation treatment were examined by Western blot. Pretreatment with nimotuzumab reduced clonogenic survival after radiation, inhibited radiation-induced EGFR activation and increased the radiation-induced apoptosis in both A549 cells and MCF-7 cells. The foci of γ-H2AX 24 h after radiation significantly increased in nimotuzumab pretreated cells with different doses. The phosphorylation of AKT and DNA-PKcs were remarkably inhibited in the combination group at each dose point as well as time point. Conclusions: Our results revealed that the possible mechanism of nimotuzumab enhancing the cancer radiosensitivity is that nimotuzumab inhibited the radiation-induced activation of DNA-PKcs through blocking the PI3K/AKT pathway, which ultimately affected the DNA DSBs repair. [ABSTRACT FROM AUTHOR]