Publications by authors named "HaoYu Shi"

8 Publications

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Energy release induced rockbursts based on butterfly-shaped plastic zones in roadways of coal reservoirs.

PLoS One 2021 28;16(7):e0255044. Epub 2021 Jul 28.

North China Institute of Science and Technology, Beijing, China.

According to the theories of rockburst based on butterfly-shaped plastic zones, a plane strain mechanical model was established for stress distribution around the holes in homogeneous elastoplastic media. Based on the Mohr-Coulomb yield criterion and the generalized form of Hooke's law, the equation for the elastic strain-energy density of units at a 3D stress state was deduced. On this basis, the energy absorption and release in rocks surrounding a roadway during the evolution thereof in a coal reservoir tend to rock bursting were quantified. Through Flac3D 5.0 numerical simulation software, the energy released from a homogeneous circular roadway at different development states of plastic zones was investigated. By investigating conditions at the 21141 working face in Qianqiu Coal Mine, Henan Province, China, subjected to rockburst, a numerical model was established to calculate the energy released by a rockburst working face. The calculated results approximated the data monitored at the outburst site, with the same energy level recorded. The theoretical calculation for energy release from the rock surrounding a roadway is expected to reference engineering practice.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0255044PLOS
July 2021

Role of integrin‑linked kinase in static compressive stress‑induced autophagy via phosphatidylinositol 3 kinase in human periodontal ligament cells.

Int J Mol Med 2021 Sep 19;48(3). Epub 2021 Jul 19.

Key Laboratory of Shaanxi Province for Craniofacial Precision Medicine Research, College of Stomatology, Xi'an Jiaotong University, Xi'an, Shaanxi 710004, P.R. China.

Orthodontic tooth movement (OTM) is achieved by using mechanical stimuli, which lead to the remodeling of periodontal tissues. Previous findings have demonstrated that autophagy may be one of the cell responses to mechanical stress. As a key structure in the integrin pathway, integrin linked‑kinase (ILK) may play a role in the transmission of these mechanical signals. In addition, ILK is an important upstream molecule that regulates autophagy, under the influence of phosphatidylinositol 3 kinase (PI3K). Therefore, exploring the effect of mechanical stress on autophagy and the associated role of ILK/PI3K is of utmost significance to understanding the mechanism behind OTM. In the present study, human periodontal ligament cells (hPDLCs) were embedded into a collagen‑alginate complex hydrogel for three‑dimensional (3D) culturing. Static compressive stress (2.5 g/cm) was loaded using the uniform weight method for 5, 15, 30, and 60 min. The autophagy of hPDLCs was detected by the expression of Beclin‑1 () and using RT‑qPCR and LC3, respectively, using immunofluorescence. The results showed that the level of autophagy and gene expression of increased significantly under static compressive stress. In ILK‑silenced cells, static compressive stress could also upregulate ILK expression and increase the levels of autophagy. After PI3K inhibition, the increase in the autophagy level and the upregulation of expression disappeared. These findings suggest that static compressive stress can induce autophagy in hPDLCs in a rapid, transient process, regulated by ILK and PI3K. Moreover, this static stress can upregulate expression in a PI3K‑dependent manner.
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http://dx.doi.org/10.3892/ijmm.2021.5000DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8285053PMC
September 2021

Corrosion Evaluation of Pure Mg Coated by Fluorination in 0.1 M Fluoride Electrolyte.

Scanning 2021 13;2021:5574946. Epub 2021 May 13.

The Conversationalist Club, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

In the ongoing research on the application of biodegradable materials, surface treatment of is considered to be a relatively effective solution to the excessive degradation rates of Mg alloys. In this study, to further optimize the proven effective surface coatings of fluoride, a low-voltage preparation fluorination method was used to achieve coating effectiveness under safer conditions. Optical observation, scanning electron microscopy (SEM), X-ray diffraction (XRD), energy-dispersive spectroscopy (EDS), and potential dynamic polarization (PDP) experiments were used for the analysis and evaluation. The coating characteristics of the MgF coatings treated in the 10-90 V voltage range, including the structure, chemical conformation, and electrochemical corrosion assessment, were fully defined. The anodic fluoridation results showed that a pore structure of 1-14 m thickness was formed on the Mg alloy substrate, and the coating was composed of Mg fluoride. The results of immersion corrosion and electrochemical corrosion experiments showed that compared with pure Mg, anodic fluorinated samples below 40 V exhibited better corrosion resistance, the prepared MgF coating was more uniform, and the surface mostly exhibited point corrosion. When the voltage reached or exceeded 60 V, the prepared coating exhibited poor corrosion resistance, fracture, and protrusions. After corrosion, it mostly exhibited surface corrosion. The results indicate that idealized coatings can be obtained at relatively low and safe voltage ranges. This finding may enable more economical, environmentally friendly, and safe preparation of coatings.
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http://dx.doi.org/10.1155/2021/5574946DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8140829PMC
June 2021

Analysis of Three-Dimensional Morphological Differences in the Mandible between Skeletal Class I and Class II with CBCT Fixed-Point Measurement Method.

Scanning 2021 7;2021:9996857. Epub 2021 May 7.

Department of Stomatology, The Affiliated Hospital of Qingdao University, Qingdao, 266003 Shandong, China.

This study was aimed at determining the three-dimensional differences in the mandible morphology between skeletal class I and II patients, at exploring the pathogenic mechanisms and morphological characteristics of skeletal class II, and at providing clinical references. The subjects were assigned to two groups according to the size of ANB angle: skeletal class I (2° < ANB angle < 5°) and skeletal class II (5° < ANB angle < 8°). After cone-beam computed tomography (CBCT) scanning, 31 landmarks and 25 measurement items were determined by In Vivo Dental 5.1 software (Anatomage, CA) for statistical analysis. The results were as follows: Co-Go, Go-Me, and CdM-CdD in skeletal class II cases were smaller than those in skeletal class I, and GoR-Me-GoL, GoR-Me-CoL, and, Ig-Men were larger than those in skeletal class I cases. In conclusion, there were significant differences in the three-dimensional morphology of the mandible between skeletal class I and class II patients. The vertical growth of the ramus, the horizontal growth of the mandibular body, and the condyle in skeletal class II patients were smaller than those in skeletal class I cases. In skeletal class II, the growth of the anterior part of the mandible in the vertical direction was larger than that in skeletal class I, and the shape of the mandible was more extended.
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http://dx.doi.org/10.1155/2021/9996857DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8121591PMC
May 2021

Corrosion Behavior of Biodegradable Magnesium Alloy by MAF Treatment.

Scanning 2021 3;2021:5530788. Epub 2021 May 3.

The Conversationalist Club, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

Coating treatment plays an irreplaceable role in propelling the clinical application of magnesium alloys. This experiment was designed in order to observe the anticorrosion behavior of magnesium fluoride coating in rats. The MgF layer was prepared on the surface of AZ31 magnesium alloy in saturated NHHF solution by microarc fluorination (MAF) at 190 V. The cross-sectional SEM, EDS, and XRD analysis indicated that the alloy surface was covered with MgF. Meanwhile, SEM observation was used to compare the magnesium alloy samples before and after treatment, and it was found that the samples after coating were flatter and smoother. Two sets of experiments were carried out with the subjects, 6-week-old male rats. So that the untreated AZ31 samples and the microarc fluorinated AZ31 samples could be buried under the muscle layer individually. The volume changes and surface morphology of the corroded samples were monitored dynamically using micro-CT over a 16-week period . Comparison of results between the two sets of samples presented that the corrosion of the microarc fluoridated samples was much slower than that of the untreated ones. The MAF coating was shown to be effective in controlling the corrosion rate and progression of the magnesium alloy.
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http://dx.doi.org/10.1155/2021/5530788DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8112943PMC
May 2021

Accuracy and Precision Evaluation of International Standard Spherical Model by Digital Dental Scanners.

Scanning 2020 9;2020:1714642. Epub 2020 Dec 9.

Stomatological Materials Laboratory, School of Stomatology, Shandong First Medical University & Shandong Academy of Medical Sciences, Tai'an, Shandong 271016, China.

With the popularization of digital technology and the exposure of traditional technology's defects, computer-aided design and computer-aided manufacturing (CAD/CAM) has been widely used in the field of dentistry. And the accuracy of the scanning system determines the ultimate accuracy of the prosthesis, which is a very important part of CAD/CAM, so we decided to evaluate the accuracy of the intraoral and extraoral scanners. In this study, we selected the sphere model as the scanning object and obtained the final result through data analysis and 3D fitting. In terms of trueness and precision, the scanner of SHINING was significantly different from that of others; however, there was no significant difference between TRIOS and CEREC. SHINING showed the lowest level of accuracy, with CEREC slightly lower than TRIOS. The sphere model has also been proven to be scanned successfully.
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http://dx.doi.org/10.1155/2020/1714642DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787873PMC
December 2020

Calcium requirements for Chinese adults by cross-sectional statistical analyses of calcium balance studies: an individual participant data and aggregate data meta-regression.

Chin Med J (Engl) 2014 ;127(24):4250-7

Department of Nutrition and Food Hygiene, Peking University Health Science Center, Haidian District, Beijing 100191, China.

Background: Chinese dietary reference intakes for calcium are largely based on foreign studies. We undertook meta-regression to estimate calcium requirements for Chinese adults derived from calcium balance data in Chinese adults.

Methods: We searched PubMed, Cochrane CENTRAL, and SinoMed from inception to March 5, 2014, by using a structured search strategy. The bibliographies of any relevant papers and journals were also screened for potentially eligible studies. We extracted a standardized data set from studies in Chinese adults that reported calcium balance data. The relationship between calcium intake and output was examined by an individual participant data (IPD) and aggregate data (AD) meta-regression.

Results: We identified 11 metabolic studies in Chinese adults within 18-60 years of age. One hundred and forty-one IPD (n = 35) expressed as mg/d, 127 IPD (n = 32) expressed as mg×kg body wt(-1)×d(-1), and 44 AD (n = 132) expressed as mg/d were collected. The models predicted a neutral calcium balance (defined as calcium output (Y) equal to calcium intake (C)) at intakes of 460 mg/d (Y = 0.60C+183.98) and 8.27 mg×kg body wt(-1)×d(-1) (Y = 0.60C+3.33) for IPD, or 409 mg/d (Y = 0.66C+139.00) for AD. Calcium requirements at upper intakes were higher than that at lower intakes in all these models.

Conclusion: Calcium requirement for Chinese adults 18-60 years of age approximately ranges between 400 mg/d and 500 mg/d when consuming traditional plant-based Chinese diets.
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August 2015

Surface-Modified TiO Photocatalysts Prepared by a Photosynthetic Route: Mechanism, Enhancement, and Limits.

Chempluschem 2014 Jan 11;79(1):163-170. Epub 2013 Dec 11.

Faculty of Chemistry and Biochemistry, Ruhr-Universität Bochum, Universitätsstrasse 150 NC 4/073, 44780 Bochum (Germany), Fax: (+49) (0)234-32-14174.

Surface-modified TiO photocatalysts were synthesized by a photosynthetic route involving visible-light-induced (λ>455 nm) activation of benzene and toluene at the surface of TiO leading to the formation of carbonaceous polymeric deposits. IR spectroscopic and photoelectrochemical experiments showed that the mechanism of the photosynthetic reactions involves intra-bandgap surface states at TiO related to surface OH groups interacting with adsorbed aromatic molecules. The photosynthesized surface-modified TiO materials exhibited enhanced activity, relative to pristine TiO , in photocatalytic degradation (and complete mineralization) of 4-chlorophenol. The improvement was pronounced particularly under visible-light (λ>455 nm) irradiation with the relative initial photodegradation rate enhanced by a factor of four. The surface-modified photocatalysts exhibited good stability under the operating conditions, and the optimum carbon content was approximately 0.5 wt %. Mechanistic studies showed that the enhanced visible-light photodegradation of 4-chlorophenol is due to modified surface-adsorption properties that facilitate formation of a surface complex between titania and 4-chlorophenol, rather than due to any sensitizing effect of the carbonaceous deposits. The study highlights the importance of considering the interaction between pollutant molecules and the photocatalyst surface in heterogeneous photocatalysis, and possibly opens up a route for photosynthesis of further surface-modified photocatalysts with tuned surface properties.
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http://dx.doi.org/10.1002/cplu.201300277DOI Listing
January 2014
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