Publications by authors named "Wei Hang"

136 Publications

Single-Cell Mass Spectrometry Imaging of Multiple Drugs and Nanomaterials at Organelle Level.

ACS Nano 2021 Jul 27. Epub 2021 Jul 27.

Ministry of Education (MOE) Key Laboratory of Spectrochemical Analysis and Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.

Mass spectrometry imaging (MSI) techniques make possible the spatial chemical identification of analytes, especially for biological samples. As a universal energy source, laser is one of the most commonly used sampling methods in MSI techniques. However, due to the limitation of laser spot size, subcellular spatial resolution imaging, which is significant for life science researches, always remains a challenge for laser-based MSI. In this research, we designed a laser ablation (LA) system with a microlensed fiber and a "three-way" structure ablation chamber, and achieved nanoscale inductively coupled plasma (ICP) MSI with an adjustable spatial resolution down to 400 nm, which surpasses most existing technologies. With this device, the distribution of various photodynamic therapy drugs in the intestine of mouse can be clearly observed. The comparison imaging results showed that the drug distribution in tissue slice could be identified at the subcellular level with the high-resolution mode. More valuably, gold nanorods (GNRs) and carboplatin in a single cell are able to be visualized at organelle level due to the nanoscale resolution, which is able to reveal the mechanism of cell apoptosis. This reliable and economical MSI technique is expected to be used in understanding the precise chemical composition and transportation in small tissues, microorganisms, and single cells.
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http://dx.doi.org/10.1021/acsnano.1c02922DOI Listing
July 2021

[Experience in the diagnosis and treatment of the postoperative complications of craniopharyngiomas through expanded endoscopic endonasal transsphenoidal approach].

Lin Chung Er Bi Yan Hou Tou Jing Wai Ke Za Zhi 2021 Jun;35(6):505-510

Department of Otorhinolaryngology Head and Neck Surgery,Tianjin Huanhu Hospital,Tianjin,300350,China.

To summarize the clinical characteristics of the postoperative complications of surgical resection of craniopharyngiomas through expanded endoscopic endonasal transsphenoidal approach (EEETA). Strategies for prevention and management were also discussed. The clinical data of the patients who were treated through EEETA were retrospectively reviewed. The occurrence of post-operative complications were recorded. Partial removal of the tumors were accomplished in 11 cases and subtotal removal in 4 cases. The major postoperative complications were anterior pituitary hypofunction(11/15), diabetes insipidus(8/15), epistaxis(3/15), cerebrospinal fluid rhinorrhea(1/15). The cases were treated symptomatically or by re-operation. Of all the cases,10 patients were improved,1 patient had drowsiness,3 suffered from multiple organ failure,and 1 patient died. To prevent and reduce the postoperative complications of EEETA, first of all, it is essential to evaluate the need for surgical intervention and perform a comprehensive preoperative assessment. Critical nerves and vessels should be preserved carefully during operation for the sake of avoiding injuries normal pituitary and hypothalamus. Furthermore, reconstruction of the skull base is critical. The standard procedure of nasal endoscopy and the experience of the surgeons are quite significant, while the operation needs multidisciplinary collaborations.
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http://dx.doi.org/10.13201/j.issn.2096-7993.2021.06.005DOI Listing
June 2021

Construction of a molybdenum and copper co-doped nickel phosphide with lattice distortion for highly efficient electrochemical water splitting.

Dalton Trans 2021 Jul;50(28):9690-9694

College of Chemistry and Chemical Engineering, Inner Mongolia Engineering and Technology Research Center for Catalytic Conversion and Utilization of Carbon Resource Molecules, Inner Mongolia University, Hohhot 010021, China.

A self-supported dual-cation (Mo,Cu) co-doped [email protected] nickel foam catalyst (Mo,[email protected]) has been prepared, and the co-doped samples can distort the lattice and expose a larger specific surface area, which provides more reaction locations, and exhibit an efficient water splitting performance.
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http://dx.doi.org/10.1039/d1dt02019fDOI Listing
July 2021

Smart Materials for Dynamic Thermal Radiation Regulation.

Small 2021 Sep 20;17(35):e2100446. Epub 2021 May 20.

Center for Composite Materials and Structure, Harbin Institute of Technology, Harbin, 150001, China.

Thermal radiation in the mid-infrared region profoundly affects human lives in various fields, including thermal management, imaging, sensing, camouflage, and thermography. Due to their fixed emissivities, radiance features of conventional materials are usually proportional to the quadruplicate of surface temperature, which set the limit, that one type of material can only present a single thermal function. Therefore, it is necessary and urgent to design materials for dynamic thermal radiation regulations to fulfill the demands of the age of intelligent machines. Recently, the ability of some smart materials to dynamically regulate thermal radiation has been evaluated. These materials are found to be competent enough for various commands, thereby, providing better alternatives and tremendously promoting the commercial potentials. In this review, the dynamic regulatory mechanisms and recent progress in the evaluation of these smart materials are summarized, including thermochromic materials, electrochromic materials, mechanically and humidity responsive materials, with the potential applications, insufficient problems, and possible strategies highlighted.
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http://dx.doi.org/10.1002/smll.202100446DOI Listing
September 2021

Effect of Unit Cell Shape on Switchable Infrared Metamaterial VO Absorbers/Emitters.

Research (Wash D C) 2021 22;2021:9804183. Epub 2021 Apr 22.

Center for Composite Materials and Structure, Harbin Institute of Technology, Harbin 150001, China.

Metamaterial absorber/emitter is an important aspect of infrared radiation manipulation. In this paper, we proposed four simple switchable infrared metamaterial absorbers/emitters with Ag/VO disks on the Ag plane employing triangle, square, hexagon, and circle unit cells. The spectral absorption peaks whose intensities are above 0.99 occur at ~4 m after structure optimization when VO is in insulating state and disappear when VO becomes metallic state. The simulated electromagnetic field reveals that the spectral absorption peaks are attributed to the excitation of magnetic polariton within the insulating VO spacer layer, whose values exceed 1.59 orders of magnitude higher than the incident magnetic field. Longer resonant wavelength would be excited in square arrays because its configuration is a better carrier of charges at the same spans. For absorption stability, the absorbers/emitters with square and circular structures do not have any change with the polarization angles changing from 0° to 90°, due to the high rotational symmetric structure. And four absorbers/emitters reveal similar shifts and attenuations under different incident angles. We believed that the switchable absorber/emitter demonstrates promising applications in the sensing technology and adaptive infrared system.
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http://dx.doi.org/10.34133/2021/9804183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8087995PMC
April 2021

iCircDA-LTR: identification of circRNA-disease associations based on Learning to Rank.

Bioinformatics 2021 May 8. Epub 2021 May 8.

School of Computer Science and Technology, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China.

Motivation: Due to the inherent stability and close relationship with the progression of diseases, circRNAs are serving as important biomarkers and drug targets. Efficient predictors for identifying circRNA-disease associations are highly required. The existing predictors consider circRNA-disease association prediction as a classification task or a recommendation problem, failing to capture the ranking information among the associations and detect the diseases associated with new circRNAs. However, more and more circRNAs are discovered. Identification of the diseases associated with these new circRNAs remains a challenging task.

Results: In this study, we proposed a new predictor called iCricDA-LTR for circRNA-disease association prediction. Different from any existing predictor, iCricDA-LTR employed a ranking framework to model the global ranking associations among the query circRNAs and the diseases. The Learning to Rank (LTR) algorithm was employed to rank the associations based on various predictors and features in a supervised manner. The experimental results on two independent test datasets showed that iCircDA-LTR outperformed the other competing methods, especially for predicting the diseases associated with new circRNAs. As a result, iCircDA-LTR is more suitable for the real world applications.

Availability: For the convenience of researchers to detect new circRNA-disease associations. The web server of iCircDA-LTR was established and freely available at http://bliulab.net/iCircDA-LTR/.
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http://dx.doi.org/10.1093/bioinformatics/btab334DOI Listing
May 2021

[Geochemical Survey Method of Land Quality in Land Parcel Scale City: A Case Study of the Initial Area of the Xiong'an New District].

Huan Jing Ke Xue 2021 Apr;42(4):1989-2002

Institute of Geophysical & Geochemical Exploration, Chinese Academy of Geological Sciences, Langfang 065000, China.

In order to evaluate the land quality geochemical survey achievement in the service of the accurate management of urban land resources, the initial area of the Xiong'an New District as urbanization pathfinder in China is chosen as the research subject. The sample points were set by differential classification, and the spatial interpolation accuracy of the soil elements at a plot scale and a quantitative assessment of the consistency of the land plot (pattern spot) prediction evaluation were studied under the conditions of different sampling densities. The regional geochemical variation values randomly distributed on the plane can be reflected quantitatively by differential classification sampling, which can meet the basic demand of the quality attribute of a single plot (map spot) by the accurate management of urban land resources. The spatial variability of soil elements is mostly middle to moderate, and Cd, Cu, Pb, Hg, Se, N, P, and other elements of high spatial variability are affected by human industrial and agricultural production activities. Under the same sampling density, the larger the element variation coefficient, the worse the spatial interpolation accuracy. Although the interpolation accuracy of the same element index is affected by the sampling density, the increase in the sampling density could not identify the continuous component on the structure of the soil element content. The soil environment is clean, and the heavy metal content is lower than the GB15618-2018 standard. The interpolation results are basically consistent with the grading results of the measured values, while the contents of N, P, and K of the nutrient indices vary greatly, and the predicted and measured geochemical grades of the plots (map spot) differ substantially under the influence of factors such as human disturbance and spatial variability. The quantitative evaluation of the six different sampling densities indicates that the 16 points·km sampling density adopted in the geochemical survey and evaluation of urban land quality can satisfy the needs of an accurate control of urban land resources in the study area and similar areas. The research can provide key technologies to support and serve the accurate management of urban land resources for geochemical surveys and the evaluation of land quality in land parcel scale cities.
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http://dx.doi.org/10.13227/j.hjkx.202008133DOI Listing
April 2021

Characterization of type-2 diacylglycerol acyltransferases in Haematococcus lacustris reveals their functions and engineering potential in triacylglycerol biosynthesis.

BMC Plant Biol 2021 Jan 6;21(1):20. Epub 2021 Jan 6.

College of Agriculture, Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu, 030801, Shanxi, China.

Background: Haematococcus lacustris is an ideal source of astaxanthin (AST), which is stored in oil bodies containing esterified AST (EAST) and triacylglycerol (TAG). Diacylglycerol acyltransferases (DGATs) catalyze the last step of acyl-CoA-dependent TAG biosynthesis and are also considered as crucial enzymes involved in EAST biosynthesis in H. lacustris. Previous studies have identified four putative DGAT2-encoding genes in H. lacustris, and only HpDGAT2D allowed the recovery of TAG biosynthesis, but the engineering potential of HpDGAT2s in TAG biosynthesis remains ambiguous.

Results: Five putative DGAT2 genes (HpDGAT2A, HpDGAT2B, HpDGAT2C, HpDGAT2D, and HpDGAT2E) were identified in H. lacustris. Transcription analysis showed that the expression levels of the HpDGAT2A, HpDGAT2D, and HpDGAT2E genes markedly increased under high light and nitrogen deficient conditions with distinct patterns, which led to significant TAG and EAST accumulation. Functional complementation demonstrated that HpDGAT2A, HpDGAT2B, HpDGAT2D, and HpDGAT2E had the capacity to restore TAG synthesis in a TAG-deficient yeast strain (H1246) showing a large difference in enzymatic activity. Fatty acid (FA) profile assays revealed that HpDGAT2A, HpDGAT2D, and HpDGAT2E, but not HpDGAT2B, preferred monounsaturated fatty acyl-CoAs (MUFAs) for TAG synthesis in yeast cells, and showed a preference for polyunsaturated fatty acyl-CoAs (PUFAs) based on their feeding strategy. The heterologous expression of HpDGAT2D in Arabidopsis thaliana and Chlamydomonas reinhardtii significantly increased the TAG content and obviously promoted the MUFAs and PUFAs contents.

Conclusions: Our study represents systematic work on the characterization of HpDGAT2s by integrating expression patterns, AST/TAG accumulation, functional complementation, and heterologous expression in yeast, plants, and algae. These results (1) update the gene models of HpDGAT2s, (2) prove the TAG biosynthesis capacity of HpDGAT2s, (3) show the strong preference for MUFAs and PUFAs, and (4) offer target genes to modulate TAG biosynthesis by using genetic engineering methods.
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http://dx.doi.org/10.1186/s12870-020-02794-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7788937PMC
January 2021

Gold Nanoparticles on Nanosheets Derived from Layered Rare-Earth Hydroxides for Catalytic Glycerol-to-Lactic Acid Conversion.

ACS Appl Mater Interfaces 2021 Jan 4;13(1):522-530. Epub 2021 Jan 4.

College of Chemistry and Chemical Engineering, Inner Mongolia Engineering and Technology Research Center for Catalytic Conversion and Utilization of Carbon Resource Molecules, Inner Mongolia University, Hohhot 010021, China.

Layered rare-earth hydroxides (LREHs), as a series of special lamellar compounds having a similar structure to layered double hydroxides (LDHs), are becoming a new type of catalyst materials. In this study, we have prepared a series of uniform LREH (RE = Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, and Tm) nanosheets through a reverse-microemulsion method. After deposition-precipitation of HAuCl and calcination, supported Au catalysts (denoted as Au/LREO) were subsequently obtained. The catalytic properties of all the derived Au/LREO catalysts were evaluated by aerobic conversion of glycerol to lactic acid under mild conditions (90 °C, 1 atm). Among these catalysts, Au/LPrO displays the best performances, including the highest glycerol conversion, lactic acid, and C product selectivity. Both the catalytic activities and the characterizations of the structure of Au/LREO indicate that the kind of rare-earth ions plays a key role in determining the Au particle size and its valence state and reducibility, which are the important factors correlated with the catalytic activities in glycerol conversion. In fact, the three features of gold particles, the extra-small size (∼3 nm), high content of Au species, and high reducibility, are the essential prerequisites for achieving the superior catalytic performance of Au/LPrO.
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http://dx.doi.org/10.1021/acsami.0c17732DOI Listing
January 2021

Characterization of a Novel Acyl-ACP Δ Desaturase Gene Responsible for Palmitoleic Acid Accumulation in a Diatom .

Front Microbiol 2020 16;11:584589. Epub 2020 Dec 16.

College of Agriculture, Shanxi Agricultural University, Jinzhong, China.

Palmitoleic acid (16:1Δ) possesses a double bond at the seventh carbon atom from methyl end of the acyl chain and belongs to unusual ω-7 monounsaturated fatty acids with broad applications in food, pharmaceuticals, cosmetics, biofuel, and other industries. This high-value fatty acid accumulates up to >40% of total lipid in the marine diatom The present study was conducted to determine the key gene responsible for 16:1Δ biosynthesis in this unicellular alga. A new full-length cDNA and genomic DNA encoding acyl-ACP Δ desaturase (PtAAD) were isolated from cells. Expression levels of gene under normal and stress culture conditions were both positively correlated with 16:1Δ accumulation, implying its potential role for fatty acid determination. Functional complementation assay of a yeast mutant strain evidenced that could restore the synthesis of unsaturated fatty acid, especially generating high levels of 16:1Δ. Further transient expression of gene in leaves was accompanied by the accumulation of 16:1Δ, which was absent from control groups. Three-dimensional structure modeling studies showed that functional domain of PtAAD contained three variant amino acids (F160, A223, and L156), which may narrow the space shape of substrate-binding cavity to ensure the entry of 16:0-ACP. Consistent with this prediction, the mutated version of gene (F160L, A223T, and L156M) in systems failed to accumulate 16:1Δ, but increased levels of 18:1Δ. Taken together, PtAAD exhibits a strong enzymatic activity and substrate preference for 16:0-ACP, acting as the key player for high biosynthesis and accumulation of 16:1Δ in this alga. These findings provide new insights for better understanding the palmitoleic acid and oil biosynthetic mechanism in , indicating that gene may have practical applications for enriching palmitoleic acid and oil yield in other commercial oleaginous algae and crops.
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http://dx.doi.org/10.3389/fmicb.2020.584589DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7772203PMC
December 2020

iPiDA-sHN: Identification of Piwi-interacting RNA-disease associations by selecting high quality negative samples.

Comput Biol Chem 2020 Oct 29;88:107361. Epub 2020 Aug 29.

School of Computer Science and Technology, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China; School of Computer Science and Technology, Beijing Institute of Technology, Beijing 100081, China; Advanced Research Institute of Multidisciplinary Science, Beijing Institute of Technology, Beijing 100081, China. Electronic address:

As a large group of small non-coding RNAs (ncRNAs), Piwi-interacting RNAs (piRNAs) have been detected to be associated with various diseases. Identifying disease associated piRNAs can provide promising candidate molecular targets to promote the drug design. Although, a few computational ensemble methods have been developed for identifying piRNA-disease associations, the low-quality negative associations even with positive associations used during the training process prevent the predictive performance improvement. In this study, we proposed a new computational predictor named iPiDA-sHN to predict potential piRNA-disease associations. iPiDA-sHN presented the piRNA-disease pairs by incorporating piRNA sequence information, the known piRNA-disease association network, and the disease semantic graph. High-level features of piRNA-disease associations were extracted by the Convolutional Neural Network (CNN). Two-step positive-unlabeled learning strategy based on Support Vector Machine (SVM) was employed to select the high quality negative samples from the unknown piRNA-disease pairs. Finally, the SVM predictor trained with the known piRNA-disease associations and the high quality negative associations was used to predict new piRNA-disease associations. The experimental results showed that iPiDA-sHN achieved superior predictive ability compared with other state-of-the-art predictors.
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http://dx.doi.org/10.1016/j.compbiolchem.2020.107361DOI Listing
October 2020

SMI-BLAST: a novel supervised search framework based on PSI-BLAST for protein remote homology detection.

Bioinformatics 2021 05;37(7):913-920

School of Computer Science and Technology, Harbin Institute of Technology, Shenzhen, Guangdong 518055, China.

Motivation: As one of the most important and widely used mainstream iterative search tool for protein sequence search, an accurate Position-Specific Scoring Matrix (PSSM) is the key of PSI-BLAST. However, PSSMs containing non-homologous information obviously reduce the performance of PSI-BLAST for protein remote homology.

Results: To further study this problem, we summarize three types of Incorrectly Selected Homology (ISH) errors in PSSMs. A new search tool Supervised-Manner-based Iterative BLAST (SMI-BLAST) is proposed based on PSI-BLAST for solving these errors. SMI-BLAST obviously outperforms PSI-BLAST on the Structural Classification of Proteins-extended (SCOPe) dataset. Compared with PSI-BLAST on the ISH error subsets of SCOPe dataset, SMI-BLAST detects 1.6-2.87 folds more remote homologous sequences, and outperforms PSI-BLAST by 35.66% in terms of ROC1 scores. Furthermore, this framework is applied to JackHMMER, DELTA-BLAST and PSI-BLASTexB, and their performance is further improved.

Availability And Implementation: User-friendly webservers for SMI-BLAST, JackHMMER, DELTA-BLAST and PSI-BLASTexB are established at http://bliulab.net/SMI-BLAST/, by which the users can easily get the results without the need to go through the mathematical details.

Supplementary Information: Supplementary data are available at Bioinformatics online.
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http://dx.doi.org/10.1093/bioinformatics/btaa772DOI Listing
May 2021

Laser-induced acoustic desorption coupled with electrospray ionization mass spectrometry for rapid qualitative and quantitative analysis of glucocorticoids illegally added in creams.

Analyst 2020 Oct;145(20):6625-6631

Department of Chemistry and the MOE Key Lab of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

We present a strategy for the coupling of laser-induced acoustic desorption (LIAD) with electrospray ionization (ESI) mass spectrometry. Different from desorption electrospray ionization (DESI) or paper spray ionization (PSI), the technique decouples the desorption of analytes from the subsequent ionization. The desorption is initiated by a shock wave induced in 10 μm titanium (Ti) foil coated with the sample, irradiated from the rear side by a laser beam, and then the desorbed neutral analytes are post-ionized by ESI and finally characterized by quadrupole/time-of-flight (Q-TOF) mass spectrometry (MS). Separating desorption from the ionization event makes this technique flexible and decreases the matrix effect and salt effect. Various kinds of common creams containing glucocorticoids are investigated using LIAD/ESI/MS without sample pretreatment. The results show that volatile and nonvolatile analytes in creams are sampled simultaneously by LIAD, providing a convenient way for high-throughput screening of the target compounds. In addition, quantitation of glucocorticoids in creams was performed by analyzing samples with decreasing concentrations of analytes (dexamethasone (20 μg g-1) used as an internal standard (IS)), until no more signal was observed. The limits of detection (LODs) of glucocorticoids were determined experimentally to be ranging from 0.7 μg g-1 for triamcinolone acetonide to 10 μg g-1 for beclomethasone dipropionate, which are two orders of magnitude lower than the regular usage of glucocorticoids (beclomethasone dipropionate 0.25 mg g-1, triamcinolone acetonide 0.25 mg g-1). Overall, LIAD/ESI/MS is demonstrated to be of great practical importance for rapid qualitative and quantitative analysis of glucocorticoids in creams, and good sensitivity can be achieved without tedious sample pretreatment and time-consuming chromatographic separation, irrespective of the presence of complex matrices.
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http://dx.doi.org/10.1039/d0an00962hDOI Listing
October 2020

The Mechanism of Layer Stacked Clamping (LSC) for Polishing Ultra-Thin Sapphire Wafer.

Micromachines (Basel) 2020 Aug 6;11(8). Epub 2020 Aug 6.

Ultra-Precision Machining Centre, College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014, China.

Double-sides polishing technology has the advantages of high flatness and parallelism, and high polishing efficiency. It is the preferred polishing method for the preparation of ultra-thin sapphire wafer. However, the clamping method is a fundamental problem which is currently difficult to solve. In this paper, a layer stacked clamping (LSC) method of ultra-thin sapphire wafer which was used on double-sides processing was proposed and the clamping mechanism of layer stacked clamping (LSC) was studied. Based on the rough surface contact model of fractal theory, combining the theory of van der Waals force and capillary force, the adhesion model of the rough surfaces was constructed, and the reliability of the model was verified through experiments. Research has found that after displacement between the two surfaces the main force of the adhesion force is capillary force. The capillary force decreases with the increasing of surface roughness, droplet volume, and contact angle. For an ultra-thin sapphire wafer with a diameter of 50.8 mm and a thickness of 0.17 mm, more than 1.4 N of normal adhesion force can be generated through the LSC method. Through the double-sides polishing experiment using the LSC method, an ultra-thin sapphire wafer with an average surface roughness () of 1.52 nm and a flatness (PV) of 0.968 μm was obtained.
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http://dx.doi.org/10.3390/mi11080759DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7464148PMC
August 2020

[Effects of and on seed germination and seedling growth of invasive plants].

Ying Yong Sheng Tai Xue Bao 2020 Jul;31(7):2271-2278

College of Life Sciences, Anqing Normal University/Anhui Pro-vince Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, Anqing 246133, Anhui, China.

Invasive plants can inhibit the survival and reproduction of native species through alle-lopathy. It is not clear whether the native plants, especially the mosses in the ground layer, inf-luence the invasive plants. In this study, we examined the effects of two native moss species, and , on two malignant invasive plants, and . The effects of mosses on seed germination and seedling growth of both invasive species were determined based on the clump structure and allelopathy of the mosses. The germination rate, germination potential and germination index of the two invasive species were significantly inhibited when seeds fallen on or into the moss clump, with an order of inhibition effect: above moss clump>below moss clump>no moss. Radicle length and radicle/plumule of were significantly affected when seeds fallen into the moss clump. Moss water extracts significantly reduced germination rate, germination potential, and germination index of the two invasive plants, with these effects being concentration-dependent. To some extent, moss water extracts increased the plumule length, radicle length and radicle/plumule of seedlings, but without effect on . Both mosses showed inhibitory effects on seed germination and seedling growth of two invasive plants, with higher sensitivity of than . Along with the increases in concentration of water extract, stronger inhibitory effects were found. Therefore, mosses could partially inhibit seed germination and seedling growth of invasive plants.
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http://dx.doi.org/10.13287/j.1001-9332.202007.010DOI Listing
July 2020

3D Nanoscale Chemical Imaging of Core-Shell Microspheres via Microlensed Fiber Laser Desorption Postionization Mass Spectrometry.

Anal Chem 2020 07 7;92(14):9916-9921. Epub 2020 Jul 7.

Ministry of Education (MOE) Key Laboratory of Spectrochemical Analysis and Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University,Xiamen 361005, China.

A laser desorption postionization (LDPI) nanoscale resolution mass spectrometry imaging (MSI) technique based on a microlensed fiber is proposed for 3D imaging of microspheres which have a core-shell structure. Results show that the diameter of the sampling crater can be as small as 350 nm by introducing the desorption laser to the sample surface through the microlensed fiber. The use of laser postionization greatly solves the problem of weak signal caused by the very small sampling amount. A line scan of a sharp edge of Cr mesh shows that the imaging resolution of this method can reach to 300 nm. Through the imaging analysis of the alloy core-shell microspheres of Cr, Fe, Co, and Cu, the distribution of four elements at different positions can be observed visually. Particularly, the reconstruction 3D image of a single Nb-Zr core-shell particle demonstrates the potential of this technique in 3D imaging.
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http://dx.doi.org/10.1021/acs.analchem.0c01434DOI Listing
July 2020

Micro-Lensed Fiber Laser Desorption Mass Spectrometry Imaging Reveals Subcellular Distribution of Drugs within Single Cells.

Angew Chem Int Ed Engl 2020 10 13;59(41):17864-17871. Epub 2020 Aug 13.

Ministry of Education (MOE) Key Laboratory of Spectrochemical Analysis and Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005, China.

The visualization of temporal and spatial changes in the intracellular environment has great significance for chemistry and bioscience research. Mass spectrometry imaging (MSI) plays an important role because of its unique advantages, such as being label-free and high throughput, yet it is a challenge for laser-based techniques due to limited lateral resolution. Here, we develop a simple, reliable, and economic nanoscale MSI approach by introducing desorption laser with a micro-lensed fiber. Using this integrated platform, we achieved 300 nm resolution MSI and successfully visualized the distribution of various small-molecule drugs in subcellular locations. Exhaustive dynamic processes of anticancer drugs, including releasing from nanoparticle carriers entering nucleus of cells, can be readily acquired on an organelle scale. Considering the simplicity and universality of this nanoscale desorption device, it could be easily adapted to most of laser-based mass spectrometry applications.
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http://dx.doi.org/10.1002/anie.202002151DOI Listing
October 2020

Astaxanthin from Haematococcus pluvialis ameliorates the chemotherapeutic drug (doxorubicin) induced liver injury through the Keap1/Nrf2/HO-1 pathway in mice.

Food Funct 2020 May 14;11(5):4659-4671. Epub 2020 May 14.

Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu 030801, China.

The aim of this study is to probe a new function of astaxanthin (AST) from Haematococcus pluvialis on chemotherapeutic drug induced liver injury in mice. Doxorubicin-induced liver injury was treated with different doses of AST, and the body weight, food intake, urinalysis, liver function, and oxidative stress indexes were examined. The hepatocyte apoptosis level, pathological sections of liver tissue and the expression of antioxidant related genes were also determined. This study found that DOX could induce serious liver injury through cytotoxicity. AST treatment could decrease the level of liver function indexes (ALT, GOT, ALP and TBil), reduce the concentration of MDA and ROS, and increase the activities of SOD, CAT and GPX in the liver. AST could also repair the damaged hepatocyte in mice with liver injury and reduce the degree of the cellular apoptosis. In addition, AST could interfere with the expression of some related genes in the Keap1/Nrf2 signaling pathway by downregulating the expression of Keap1 and activating the transcription factor Nrf2 via enhancing the level of ERK, which upregulates downstream peroxiredoxins. The present research found and illustrated a new food function of AST, indicating that AST could be used in the therapy of chemotherapy induced side effects.
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http://dx.doi.org/10.1039/c9fo02429hDOI Listing
May 2020

iPiDi-PUL: identifying Piwi-interacting RNA-disease associations based on positive unlabeled learning.

Brief Bioinform 2021 May;22(3)

Accumulated researches have revealed that Piwi-interacting RNAs (piRNAs) are regulating the development of germ and stem cells, and they are closely associated with the progression of many diseases. As the number of the detected piRNAs is increasing rapidly, it is important to computationally identify new piRNA-disease associations with low cost and provide candidate piRNA targets for disease treatment. However, it is a challenging problem to learn effective association patterns from the positive piRNA-disease associations and the large amount of unknown piRNA-disease pairs. In this study, we proposed a computational predictor called iPiDi-PUL to identify the piRNA-disease associations. iPiDi-PUL extracted the features of piRNA-disease associations from three biological data sources, including piRNA sequence information, disease semantic terms and the available piRNA-disease association network. Principal component analysis (PCA) was then performed on these features to extract the key features. The training datasets were constructed based on known positive associations and the negative associations selected from the unknown pairs. Various random forest classifiers trained with these different training sets were merged to give the predictive results via an ensemble learning approach. Finally, the web server of iPiDi-PUL was established at http://bliulab.net/iPiDi-PUL to help the researchers to explore the associated diseases for newly discovered piRNAs.
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http://dx.doi.org/10.1093/bib/bbaa058DOI Listing
May 2021

Raman study of the photoinduced behavior of dye molecules on TiO() single crystal surfaces.

Chem Sci 2020 Apr 17;11(25):6431-6435. Epub 2020 Apr 17.

Department of Physics, State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, College of Energy, College of Materials, Xiamen University Xiamen 361005 China

In dye-sensitized solar cells (DSSCs), the TiO/dye interface significantly affects photovoltaic performance. However, the adsorption and photoinduced behavior of dye molecules on the TiO substrate remains unclear. Herein, shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) was used to study the adsorption and photoinduced behavior of dye (N719) molecules on different TiO() surfaces. On TiO(001) and TiO(110) surfaces, the SHINERS and mass spectrometry results indicate S[double bond, length as m-dash]C bond cleavage in the anchoring groups of adsorbed N719, whereas negligible bond cleavage occurs on the TiO(111) surface. Furthermore, DFT calculations show the stability of the S[double bond, length as m-dash]C anchoring group on three TiO() surfaces in the order TiO(001) < TiO(110) < TiO(111), which correlated well with the observed photocatalytic activities. This work reveals the photoactivity of different TiO() surface structures and can help with the rational design of DSSCs. Thus, this strategy can be applied to real-time probing of photoinduced processes on semiconductor single crystal surfaces.
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http://dx.doi.org/10.1039/d0sc00588fDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8159273PMC
April 2020

Cloning, expression, and characterization of a novel plant type cryptochrome gene from the green alga Haematococcus pluvialis.

Protein Expr Purif 2020 08 4;172:105633. Epub 2020 Apr 4.

Institute of Molecular Agriculture and Bioenergy, Shanxi Agricultural University, Taigu, 030801, China. Electronic address:

A full-length cDNA sequence of plant type CRY (designated Hae-P-CRY) was cloned from the green alga Haematococcus pluvialis. The cDNA sequence was 3608 base pairs (bp) in length, which contained a 2988-bp open reading frame encoding 995 amino acids with molecular mass of 107.7 kDa and isoelectric point of 6.19. Multiple alignment analysis revealed that the deduced amino acid sequence of Hae-P-CRY shared high identity of 47-66% with corresponding plant type CRYs from other eukaryotes. The catalytic motifs of plant type CRYs were detected in the amino acid sequence of Hae-P-CRY including the typical PHR and CTE domains. Phylogenetic analysis showed that the Hae-P-CRY was grouped together with other plant type CRYs from green algae and higher plants, which distinguished from other distinct groups. The transcriptional level of Hae-P-CRY was strongly decreased after 0-4 h under HL stress. In addition, the Hae-P-CRY gene was heterologously expressed in Escherichia coli BL21 (DE3) and successfully purified. The typical spectroscopic characteristics of plant type CRYs were present in Hae-P-CRY indicated that it may be an active enzyme, which provided valuable clue for further functional investigation in the green alga H. pluvialis. These results lay the foundation for further function and interaction protein identification involved in CRYs mediated signal pathway under HL stress in H. pluvialis.
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http://dx.doi.org/10.1016/j.pep.2020.105633DOI Listing
August 2020

Screening and Identification of Potential Biomarkers for Hepatocellular Carcinoma: An Analysis of TCGA Database and Clinical Validation.

Cancer Manag Res 2020 17;12:1991-2000. Epub 2020 Mar 17.

Department of Biochemistry, Guangzhou University of Chinese Medicine, Guangzhou 510006, People's Republic of China.

Introduction: Hepatocellular carcinoma (HCC) is the fifth most common cancer in the world. Up to now, many genes associated with HCC have not yet been identified. In this study, we screened the HCC-related genes through the integrated analysis of the TCGA database, of which the potential biomarkers were also further validated by clinical specimens. The discovery of potential biomarkers for HCC provides more opportunities for diagnostic indicators or gene-targeted therapies.

Methods: Cancer-related genes in The Cancer Genome Atlas (TCGA) HCC database were screened by a random forest (RF) classifier based on the RF algorithm. Proteins encoded by the candidate genes and other associated proteins obtained via protein-protein interaction (PPI) analysis were subjected to Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses. The newly identified genes were further validated in the HCC cell lines and clinical tissue specimens by Western blotting, immunofluorescence, and immunohistochemistry (IHC). Survival analysis verified the clinical value of genes.

Results: Ten genes with the best feature importance in the RF classifier were screened as candidate genes. By comprehensive analysis of PPI, GO and KEGG, these genes were confirmed to be closely related to HCC tumors. Representative NOX4 and FLVCR1 were selected for further validation by biochemical analysis which showed upregulation in both cancer cell lines and clinical tumor tissues. High expression of NOX4 or FLVCR1 in cancer cells predicts low survival.

Conclusion: Herein, we report that NOX4 and FLVCR1 are promising biomarkers for HCC that may be used as diagnostic indicators or therapeutic targets.
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http://dx.doi.org/10.2147/CMAR.S239795DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7085335PMC
March 2020

Metal Probe Microextraction Coupled to Dielectric Barrier Discharge Ionization-Mass Spectrometry for Detecting Drug Residues in Organisms.

Anal Chem 2020 04 31;92(8):5921-5928. Epub 2020 Mar 31.

Department of Chemistry and the MOE Key Lab of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.

In this study, a novel method for the direct coupling of metal probe microextraction (MPME) and a dielectric barrier discharge ionization (DBDI) source with mass spectrometry (MS) is reported. Analytes adsorbed on a tungsten needle were directly transferred to the DBDI source via rapid thermal desorption, which resulted in a limit of detection as low as 8 pg/mL. This is in part due to the "active capillary" configuration of the plasma ion source, where the efficiency of ion transfer to the MS is ∼100%. Specialty gases to maintain the plasma and carry analytes to the MS are not required. In contrast to direct one-step ionization of molecular adsorbates, the complete separation of the analyte desorption from the probe and the ionization event in our experimental setup greatly enhanced the sensitivity and detection reproducibility (RSD of 8.3%). We show detection of pyrimethamine, a first-line drug for the treatment and prevention of malaria all over the world, by this MPME/DBDI/MS method. The detection of drug residues in live fish and was achieved without the need for any sample pretreatment. The relative concentration of the drug in different organs of the fish was determined. This simple and convenient method has the potential for the analysis of chemicals even in single-cell organisms.
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http://dx.doi.org/10.1021/acs.analchem.0c00004DOI Listing
April 2020

Recovery of the biological function of ethylenediaminetetraacetic acid-washed soils: Roles of environmental variations and microbes.

Sci Total Environ 2020 May 30;715:137032. Epub 2020 Jan 30.

School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution and Remediation Technology, Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil Remediation, Guangzhou 510275, China; Guangdong Laboratory for Lingnan Modern Agriculture, South China Agriculture University, Guangzhou 510642, China.

To understand the recovery of the biological functions of washed soil, we studied changes in the microbial communities of soils washed with 10 or 60 mmol kg ethylenediaminetetraacetic acid (EDTA) for 90 d of incubation. The relative abundance of tolerant or degrading species decreased, while that of microorganisms with chemical autotrophic ability increased as the incubation time increased. The changes in the enzyme activity followed different trends. As an intracellular enzyme, dehydrogenase was initially most severely damaged by the washing process but could recover over time, while the activity of urease increased after washing with EDTA, which may be related to the use of N as a nutrient source by microorganisms. Phosphatase did not significantly change over time. The redundancy discriminant analyses indicated that there were distinct factors driving such changes in the soils washed with different EDTA dosages. For the soil washed with 10 mmol kg EDTA, bacteria with tolerance or degradation capacity of toxic pollutants, such as Nocardioidaceae, played a more important role in the recovery of soil functions; therefore, the EDTA stress indicator was the main driving factor. However, in the soil washed with 60 mmol kg EDTA, chemolithoautotrophic bacteria, such as Nitrososphaeraceae, exerted a greater influence on the recovery of biological functions due to the higher loss of nutrients and EDTA residue; therefore, the main driving factor was the nutrients supply.
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http://dx.doi.org/10.1016/j.scitotenv.2020.137032DOI Listing
May 2020

Effects of Zn in sludge-derived biochar on Cd immobilization and biological uptake by lettuce.

Sci Total Environ 2020 Apr 15;714:136721. Epub 2020 Jan 15.

School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution and Remediation Technology, Guangdong Provincial Engineering Research Center for Heavy Metal Contaminated Soil Remediation, Guangzhou 510275, China.

Considering the high Zn content of municipal sewage sludge and its competition with Cd during plant uptake due to their similar properties, the presence of Zn in sludge-derived biochar (SDBC) may affect Cd immobilization and uptake by plants. To confirm this, SDBC samples with different Zn contents were prepared and characterized. Their Cd immobilization behavior was studied by conducting batch sorption experiments, and their effects on Cd uptake by lettuce were explored by conducting hydroponic experiments. The results reveal that some Zn contained in the sewage sludge was transformed into ZnO during pyrolysis. The Brunauer-Emmett-Teller (BET) surface area of the SDBC samples containing 2324 mg kg Zn (BC-2324) was 18.3 m g, which was 132% larger than that of the samples containing 1438 mg kg Zn (BC-1438). The SDBC samples containing 1901 mg kg (BC-1901) exhibited the highest Langmuir sorption capacity of 3476 mg kg, which is 115% higher than that of SB-1438. Furthermore, the lettuce remedied with SB-1901 exhibited 44% more biomass; lower peroxidase, catalase, and malondialdehyde activity; and 18.4% less Cd in the leaves of the lettuce than the lettuce remedied with BC-1438, suggesting the potential benefits of using Zn-rich SDBC for soil amendment.
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http://dx.doi.org/10.1016/j.scitotenv.2020.136721DOI Listing
April 2020

iLncRNAdis-FB: identify lncRNA-disease associations by fusing biological feature blocks through deep neural network.

IEEE/ACM Trans Comput Biol Bioinform 2020 Jan 6;PP. Epub 2020 Jan 6.

Identification of lncRNA-disease associations is not only important for exploring the disease mechanism, but will also facilitate the molecular targeting drug discovery. Fusing multiple biological information is able to generate a more comprehensive view of lncRNA-disease association feature. However, the existing fusion strategies in this field fail to remove the noisy and irrelevant information from each data source. As a result, their predictive performance is still too low to be applied to real world applications. In this regard, a novel computational predictor called iLncRNAdis-FB is proposed based on the Convolution Neural Network (CNN) to integrate different data sources by using the feature blocks in a supervised manner. The lncRNA similarity matrix and disease similarity matrix are constructed, based on which the three-dimensional feature blocks are generated. These feature blocks are then fed into CNN to train the model so as to predict unknown lncRNA-disease associations. Experimental results show that iLncRNAdis-FB achieves better performance compared with other state-of-the-art predictors. Furthermore, a web server of iLncRNAdis-FB has been established at http://bliulab.net/iLncRNAdis-FB/, by which users can submit lncRNA sequences to detect their potential associated diseases.
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http://dx.doi.org/10.1109/TCBB.2020.2964221DOI Listing
January 2020

On the Room-Temperature Creep Behavior and Its Correlation with Length Scale of a Litao Single Crystal by Spherical Nanoindentation.

Materials (Basel) 2019 Dec 15;12(24). Epub 2019 Dec 15.

College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou 310014, China.

Relying on nanoindentation technology, the room-temperature creep behavior of a LiTaO single crystal in the typical orientation (01 1 ¯ 2), i.e., Y-42° plane was investigated. Three kinds of spherical tips with the radii of 0.76, 2.95 and 9.8 μm were respectively applied to detect nanoindentation length scale effect on creep deformation at both elastic and plastic regions. Superficially, both creep displacement and rate were nearly linearly increased with increasing holding depth and independent of tip size, which could be ascribed to the simultaneously enlarged holding strain and deformation volume beneath the indenter. At a similar holding strain, creep deformation, i.e., creep strain and strain rate were more pronounced under smaller spherical tips. Strain rate sensitivities of creep flows under different spherical tips and holding strains were also estimated. The potential room-temperature creep mechanism of LiTaO under high shear compression stress was discussed.
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http://dx.doi.org/10.3390/ma12244213DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6947211PMC
December 2019

Perspective on Advances in Laser-Based High-Resolution Mass Spectrometry Imaging.

Anal Chem 2020 01 9;92(1):543-553. Epub 2019 Dec 9.

Department of Chemistry, MOE Key Lab of Spectrochemical Analysis & Instrumentation, College of Chemistry and Chemical Engineering , Xiamen University , Xiamen 361005 , China.

Mass spectrometry imaging (MSI) has become a powerful tool in diverse fields, such as chemistry, physics, materials, and life science. Although such research is getting more prevalent, it is limited by high-resolution (HR) instrumental development. Recently, unceasing efforts have been made toward taking spatial resolution from the microscale to nanoscale, especially for near-field based techniques. These emerging and unique features behind high-resolution mass spectrometry imaging (HR-MSI) provide new possibilities in various aspects of biological researches. Since many technological advances provided a forefront for HR-MSI, compelling challenges including sensitivity, specificity, multimodal imaging, data acquisition, and processing follow undoubtedly. Gratifyingly, with attempts and experiences in the infancy, the emerging techniques move toward much more mature to deal with underlying conundrums in the future. Not only confined to commercial instruments, this perspective highlights recent innovations covering all emerging HR-MSI (with spatial resolution below 5 μm) techniques. Besides, vital limitations and handicaps at this stage are presented while corresponding schemes are proposed. This perspective also gives the authors' personal outlooks of developments and applications for HR-MSI in coming years.
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http://dx.doi.org/10.1021/acs.analchem.9b04067DOI Listing
January 2020

Screening chemical modulators of benzoic acid derivatives to improve lipid accumulation in SR21 with metabolomics analysis.

Biotechnol Biofuels 2019 4;12:209. Epub 2019 Sep 4.

1Department of Chemical and Biochemical Engineering, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, 361005 People's Republic of China.

Background: sp. is a marine fungus with great potential as an alternative commercial source of lipids rich in polyunsaturated fatty acids (PUFAs). To further increase lipid accumulation in sp., the effect of exogenous additives has become one of the hotspots of current research. Although benzoic acid derivatives showed positive effects on lipid accumulation in , the biochemical mechanism needs further investigation.

Results: Four benzoic acid derivatives (sodium benzoate, -aminobenzoic acid, -methyl benzoic acid and folic acid) were screened and evaluated for their effect on lipid accumulation in SR21. The lipid yield was increased by 56.84% with -aminobenzoic acid (-ABA) at a concentration of 200 mg/L among the four tested chemical modulators. The metabolomics analysis showed that 200 mg/L -ABA was optimal for promoting glucose catabolism in glycolysis with an increase in the mevalonate pathway and a weakening of the tricarboxylic acid (TCA) cycle. Moreover, -ABA increased NADPH generation by enhancing the pentose phosphate pathway (PPP), ultimately redirecting the metabolic flux to lipid synthesis. Fed-batch fermentation further proved that -ABA could significantly increase the yield of lipid by 30.01%, reaching 99.67 g/L, and the lipid content was increased by 35.03%, reaching 71.12%. More importantly, the yields of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were increased by 33.28% and 42.0%, respectively.

Conclusion: The addition of -ABA could promote the synthesis of tetrahydrofolate, enhancing NADPH, which ultimately promoted the flow of carbon flux to lipid synthesis. These findings provide a valuable strategy for improving the lipid accumulation in by additives.
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http://dx.doi.org/10.1186/s13068-019-1552-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6724347PMC
September 2019

Orientation-Independent Yield Stress and Activation Volume of Dislocation Nucleation in LiTaO Single Crystal by Nanoindentation.

Materials (Basel) 2019 Aug 30;12(17). Epub 2019 Aug 30.

Institute of Solid Mechanics, Beihang University, Beijing 100191, China.

Relying on nanoindentation technology, we investigated the elastic-to-plastic transition via first pop-in event and estimated the corresponding shear stress for incipient plasticity, i.e., yielding in the three typical orientations, i.e., X-112°, Y-36°, and Y-42° planes. The occurrence of incipient plasticity exhibited a stochastic distribution in a wide range for the three orientations. Accordingly, the obtained values of yield stress were uniform and scattered in the range from about 4 to 7 GPa for LiTaO single crystal. The orientation effect on yield stress at the nano-scale was revealed to be insignificant in LiTaO single crystal. The yield stresses were 5.44 ± 0.41, 5.74 ± 0.59, and 5.34 ± 0.525 GPa for the X-112°, Y-36°, and Y-42° planes, respectively. The activation volumes of dislocation nucleation were computed based on the cumulative distribution of yield stress, which were 12 Å, 8 Å, and 9 Å for the X-112°, Y-36°, and Y-42° planes. The results indicated that point-like defects could be the source of plastic initiation on the surface of LiTaO single crystal.
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http://dx.doi.org/10.3390/ma12172799DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6747799PMC
August 2019
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