Application of Big Data Technology in Audit

In the new era of rapid development of big data technology, the three key points of high-quality development of auditing are auditing talents, auditing rule of law and auditing technology. In the traditional audit process, auditors focus on professional judgment and professional competence, make audit plans, implement audit procedures and draw audit conclusions. However, there are many problems in traditional audit work, such as difficulty in obtaining sufficient external information and inefficiency in analyzing audit evidence. Therefore, auditors apply big data technology to audit work to solve various problems and put forward corresponding safeguard measures

Coating of manganese functional polyetheretherketone implants for osseous interface integration

Polyetheretherketone (PEEK) has been used extensively in biomedical engineering and it is highly desirable for PEEK implant to possess the ability to promote cell growth and significant osteogenic properties and consequently stimulate bone regeneration. In this study, a manganese modified PEEK implant (PEEK-PDA-Mn) was fabricated via polydopamine chemical treatment. The results showed that manganese was successfully immobilized on PEEK surface, and the surface roughness and hydrophilicity significantly improved after surface modification. Cell experiments in vitro demonstrated that the PEEK-PDA-Mn possesses superior cytocompatibility in cell adhesion and spread. Moreover, the osteogenic properties of PEEK-PDA-Mn were proved by the increased expression of osteogenic genes, alkaline phosphatase (ALP), and mineralization in vitro. Further rat femoral condyle defect model was utilized to assess bone formation ability of different PEEK implants in vivo. The results revealed that the PEEK-PDA-Mn group promoted bone tissue regeneration in defect area. Taken together, the simple immersing method can modify the surface of PEEK, giving outstanding biocompatibility and enhanced bone tissue regeneration ability to the modified PEEK, which could be applied as an orthopedic implant in clinical

Modification of silicalite-1 by vinyltrimethoxysilane (VTMS) and preparation of silicalite-1 filled polydimethylsiloxane (PDMS) hybrid pervaporation membranes

In preparation of inorganic particles filled polymer membranes, coupling agents can help to improve the compatibility between inorganic filler and polymer matrix. In this paper, surface modification of silicalite-1 was performed by a coupling agent, vinyltrimethoxysilane (VTMS), and hybrid pervaporation membranes were prepared by incorporating the unmodified or VTMS-modified silicalite-1 into polydimethylsiloxane (PDMS). The VTMS-modified silicalite-1 particles and hybrid membranes were characterized by FT-IR, (29)Si CP MAS NMR, DSC, TGA, XRD and SEM. The results showed that the coupling agent VTMS was readily grafted on the surface of silicalite-1 by hydrolysis reaction and condensation reaction, and the chemical linking between the -CH=CH(2) group on the surface-modified silicalite-1 and -Si-H on the PDMS substantially eliminated the nonselective voids inside the membrane. When used to separate acetone, butanol, ethanol (ABE) from aqueous solution, a higher selectivity was obtained with the VTMS-modified silicalite-1/PDMS hybrid membrane. Moreover, the surface modification of silicalite-1 improved its dispersion in PDMS and increased the maximal loading of silicalite-1 in membrane preparation, and thus further enhanced the separation factor of the membrane. (C) 2010 Elsevier B.V. All rights reserved

The pain regulation of endokinin A/B or endokinin C/D on chimeric peptide MCRT in mice

The present study focused on the interactive pain regulation of endokinin A/B (EKA/B, the common C-terminal decapeptide in EKA and EKB) or endokinin C/D (EKC/D, the common C-terminal duodecapeptide in EKC and EKD) on chimeric peptide MCRT (YPFPFRTic-NH2, based on YPFP-NH2 and PFRTic-NH2) at supraspinal level in mice. Results demonstrated that the co-injection of nanomolar EKA/B and MCRT showed moderate regulation, while 30 pmol EKA/B had no effect on MCRT. The combination of EKC/D and MCRT produced enhancive antinociception, which was nearly equal to the sum of mathematical value of single EKC/D and MCRT. Mechanism studies revealed that pre-injected naloxone attenuated the combination significantly with the equivalent analgesic effects of EKC/D alone, suggesting that EKC/D and MCRT might act on two totally independent pathways. Moreover, based on the above results and previous reports, we made two reasonable hypotheses to explain the cocktail-induced analgesia, which potentially pave the way to explore the respective regulatory mechanisms of EKA/B, EKC/D and MCRT and better understand the complicated pain regulation of NK1 and Îź opioid receptors, as follows: (1) MCRT and endomorphin-1 possibly activated different Îź subtypes; (2) Picomolar EKA/B might motivate the endogenous NPFF system after NK1 activation.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

Residual stress distribution of the soldered structure with Kovar alloy and Al2O3 ceramics

Residual stress distribution in soldered structure of Kovar alloy and Al2O3 ceramics was determined using XRD analyses. In order to measure the residual stress, position of the characteristic diffraction peak and stress constant were obtained using several versatile/advanced techniques after calibration. Residual stress of soldered structure was measured based on the diffraction patterns obtained for the distribution of residual stress in the soldered joint. Only diffraction peak at 149° for Kovar alloy and two diffraction peaks ranging from 140–170° for Al2O3 ceramics were found to be appropriate for the residual stress determination. It was also confirmed that for Al2O3 ceramics the XRD peak at 152° reflects the changes of stress more precisely than the one at 146°. The stress constant K of Kovar alloy and Al2O3 ceramics was found to be −197 MPa/° and −654 MPa/°, respectively. After soldering, the maximum residual stress of the soldered joint of both materials developed at 1 mm from the soldering seam, and the values within 3 mm from the soldering seam are generally significant. Thus, it is important to pay attention to the area of 3 mm from the soldering seam in practical application

Tetrazine-Containing Amino Acid for Peptide Modification and Live Cell Labeling

<div><p>A novel amino acid derivative 3-(4-(1, 2, 4, 5-tetrazine-3-yl) phenyl)-2-aminopropanoic acid was synthesized in this study. The compound possessed better water-solubility and was synthesized more easily compared with the well-known and commercially available 3-(p-benzylamino)-1, 2, 4, 5-tetrazine. Tetrazine-containing amino acid showed excellent stability in biological media and might be used for cancer cell labeling. Moreover, the compound remained relatively stable in 50% TFA/DCM with little decomposition after prolonged exposure at room temperature. The compound could be utilized as phenylalanine or tyrosine analogue in peptide modification, and the tetrazine-containing peptide demonstrated more significant biological activity than that of the parent peptide. The combination of tetrazine group and amino acid offered broad development prospects of the bioorthogonal labeling and peptide synthesis.</p></div

Synthetic route of tetrazine-containing amino acid (S)-3-(4-(1, 2, 4, 5-tetrazin-3-yl) phenyl)-2-aminopropanoic acid 2 and protected tetrazine-containing amino acid 5 and 6, and the IED-DA reaction of 2 with 5-norbornene-2-carboxylic acid 3 give 4.

<p>a) (i) Formamidine acetate (4 eq), N₂H₄ (40 eq), S (1 eq), r.t, 22 h; (ii) CH₃COOH, NaNO₂ (5 eq), 0°C, 30 min, 64.9%. b) Phosphate buffered solution (PBS), r.t, 30 min. c) Fmoc-OSu (1.5 eq), 1: 1 Dioxane/H₂O (V/V), NaHCO₃ (2.5 eq), 0°C, overnight, 64.5%. d) Boc₂O (2 eq), 1: 1 Dioxane/H₂O (V/V), NaHCO₃ (2.5 eq), 0°C, 8h, 72.3%.</p

Fluorescent microscope images of A549 lung cancer cells after pretargeting Cetuximab antibodies modified with 5-carboxyfluorescein and norbornene and subsequent labeling with tetrazine-VT680.

<p>(A) Rhodamine channel. (B) Near-IR channel (tetrazine-VT680). Images of control experiments were also taken in near infrared channel. (C) Control experiment with unlabeled cetuximab and tetrazine-VT680. (D) Control experiment with norbornene-cetuximab and unlabeled VT680.</p

The compound 2 reacted with norbornene to label cancer cells.

<p>Cancer cells A549, which overexpressed EGFR, were exposed to the Cetuximab antibodies modified with norbornene and 5-carboxyfluorescein (green). In the next step, the pretargeted cells were labeled with a tetrazine bearing a fluorophore such as VT680 (red).</p