Publications by authors named "Yin Peng"

455 Publications

The Value of Three-Dimensional Printing Spine Model in Severe Spine Deformity Correction Surgery.

Global Spine J 2021 May 11:21925682211008830. Epub 2021 May 11.

Department of Orthopedic Surgery, 74639Beijing Chao-Yang Hospital, Capital Medical University, Chaoyang District, Beijing, China.

Study Design: Retrospective case-control study.

Objective: We aimed to evaluate the value of 3-dimensional printing (3DP) spine model in the surgical treatment of severe spinal deformity since the prosperous development of 3DP technology.

Methods: Severe scoliosis or hyper-kyphosis patients underwent posterior fixation and fusion surgery using the 3DP spine models were reviewed (3DP group). Spinal deformity surgeries operated by free-hand screw implantation during the same period were selected as the control group after propensity score matching (PSM). The correction rate, pedicle screw accuracy, and complications were analyzed. Class A and B screws were defined as accurate according to Gertzbein and Robbins criteria.

Results: 35 patients were enrolled in the 3DP group and 35 matched cases were included in the control group. The perioperative baseline data and deformity correction rate were similar between both groups ( > .05). However, the operation time and blood loss were significantly less in the 3DP group (296.14 ± 66.18 min vs. 329.43 ± 67.16 min, 711.43 ± 552.28 mL vs. 1322.29 ± 828.23 mL, < .05). More three-column osteotomies (Grade 3-6) were performed in the 3DP group (30/35, 85.7% vs. 21/35, 60.0%. = .016). The screw placement accuracy was significantly higher in the 3DP group (422/582, 72.51% vs. 397/575, 69.04%. = .024). The screw misplacement related complication rate was significantly higher in the free-hand group (6/35 vs. 1/35, = .046).

Conclusions: The study provided solid evidence that 3DP spine models can enhance surgeons' confidence in performing higher grade osteotomies and improve the safety and efficiency in severe spine deformity correction surgery. 3D printing technology has a good prospect in spinal deformity surgery.
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http://dx.doi.org/10.1177/21925682211008830DOI Listing
May 2021

Lowly-aggregated perylene diimide as a near-infrared electrochemiluminescence luminophore for ultrasensitive immunosensors at low potentials.

Analyst 2021 May 6. Epub 2021 May 6.

Chemistry and Chemical Engineering College, Liaocheng University, Liaocheng, 252059, China.

In the electrochemiluminescence (ECL) field, most reported luminophores were focused on high-triggering potential and short wavelength, which was adverse for the ECL theory study and application at low potentials. Perylene diimide derivatives could emit near-infrared (NIR) ECL at low-triggering potential; however, they are always highly aggregated into a microrod structure and stacked together, which largely limited their application in biological fields such as bio-sensing and bio-imaging. To overcome these obstacles, we designed a novel perylene diimide molecule, namely N,N'-dicaproate sodium-3,4,9,10-perylenedicarboximide (PDI-COONa). This molecule self-assembled into a two-dimensional network nanostructure, which largely decreased the aggregation degree of PDI molecules and provided solid bases for designing lowly-aggregated PDI molecules. Also, the formed nanoluminophore produced strong emission at -0.26 V with an NIR wavelength 700 nm, which should be due to the excited J-type PDI-COO- dimers. Moreover, this network nanoluminophore well-dispersed on graphene oxide (GO) as an ECL nanomaterial to label secondary antibodies and fabricate a sandwiched immunosensor for alpha-fetoprotein (AFP) detection between 0 and -0.6 V. This immunosensor showed a wider linear response for AFP ranging from 0.1 fg mL-1 to 1 μg mL-1 with a low detection limit 0.0353 fg mL-1 compared with other immunosensors based on PDI microrod-modified GO ECL materials. The fabricated immunosensor also showed good feasibility in human serum samples.
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http://dx.doi.org/10.1039/d1an00410gDOI Listing
May 2021

Lack of association of somatic CAG repeat expansion with striatal neurodegeneration in HD knock-in animal models.

Hum Mol Genet 2021 May 5. Epub 2021 May 5.

Guangdong Key Laboratory of Non-Human Primate Models, Guangdong-Hongkong-Macau Institute of CNS Regeneration, Jinan University, Guangzhou, 510632.

Our previous work has established a huntingtin knock-in (KI) pig model that displays striatal neuronal loss, allowing us to examine if somatic CAG expansion in striatum accounts for the preferential neurodegeneration in Huntington disease (HD). We found that HD KI pigs do not display somatic CAG expansion in striatum as HD KI mice and that the majority of polyQ repeats in exon 1 HTT in the striatum of HD KI mice are fairly stable. We also found that striatal MSH2 and MLH3, which are involved in DNA repair, are more abundant in mouse brains than pig brains. Consistently, inhibiting MSH2 and MLH3 reduced the somatic CAG expansion in HD KI mouse striatum with no influence on neuropathology. Our findings suggest that somatic CAG expansion is species-dependent, occurs in a small fraction of the HD gene in mice, and does not critically contribute to HD neuropathology.
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http://dx.doi.org/10.1093/hmg/ddab129DOI Listing
May 2021

Estimating causes of out-of-hospital deaths in China: application of SmartVA methods.

Popul Health Metr 2021 May 4;19(1):25. Epub 2021 May 4.

Institute for Health Metrics and Evaluation, University of Washington, Seattle, USA.

Background: Most deaths in China occur at home, making it difficult to collect reliable cause of death (CoD) information. Verbal autopsy (VA) was applied using the SmartVA tool to a sample of home deaths in China to explore its feasibility as a means of improving the quality of CoD data.

Methods: The study was carried out in 22 districts in 9 provinces, located in north-east, central, and western areas of China during 2017 and 2018. Trained interviewers selected suitable respondents in each household to collect information using the Population Health Metrics Research Consortium (PHMRC) shortened and validated electronic VA questionnaire on tablets. The CoD was diagnosed from the interview data using the SmartVA-Analyze 2.0 software (Tariff 2.0).

Results: Non-communicable diseases (NCDs) dominated the leading causes of death in all age groups and for both sexes. After redistribution of undetermined causes, stroke (24%), ischemic heart diseases (IHD) (21%), chronic respiratory diseases (11%), and lung cancer (6%) were the leading causes of death. The cause fractions for level-one cause categories and ranking of specific causes were similar between SmartVA and results from the Global Burden of Disease (GBD) study.

Conclusion: Evidence from this large pilot study suggests that SmartVA is a feasible and plausible tool and could be a valuable tool to improve the quality and standardization of CoD information across China.
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http://dx.doi.org/10.1186/s12963-021-00256-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8097770PMC
May 2021

MiRNA-20b/SUFU/Wnt axis accelerates gastric cancer cell proliferation, migration and EMT.

Heliyon 2021 Apr 12;7(4):e06695. Epub 2021 Apr 12.

Guangdong Key Laboratory for Genome Stability & Disease Prevention, Department of Pathology, Shenzhen University School of Medicine, Shenzhen, Guangdong 518060, China.

Previous research has found that miRNA-20b is highly expressed in gastric cancer (GC), however, its function and underlying mechanism are not clear. Wnt signaling pathway, implicated in tumorigeneisis, is activated in more than 30% of GC. We would like to characterize the biological behavior of miRNA-20b in terms of modulating Wnt/β-catenin signaling and EMT. We showed that miRNA-20b inhibitors suppressed Topflash/Fopflash dependent luciferase activity and the β-catenin nuclear translocation, resulting in inhibition of Wnt pathway activity and EMT. SUFU, negatively regulating Wnt and Hedgehog signaling pathway, was proved to be targeted by miRNA-20b. Moreover, additional knockdown of SUFU alleviated the inhibitory effect on Wnt pathway activity, EMT, cell proliferation/migration and colony formation caused by miRNA-20b inhibition. In summary, miRNA-20b is an oncogenic miRNA and promoted cell proliferation, migration and EMT in GC partially by activating Wnt pathway via targeting SUFU.
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http://dx.doi.org/10.1016/j.heliyon.2021.e06695DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8065298PMC
April 2021

Multi-PLI: interpretable multi-task deep learning model for unifying protein-ligand interaction datasets.

J Cheminform 2021 Apr 15;13(1):30. Epub 2021 Apr 15.

Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, 518055, China.

The assessment of protein-ligand interactions is critical at early stage of drug discovery. Computational approaches for efficiently predicting such interactions facilitate drug development. Recently, methods based on deep learning, including structure- and sequence-based models, have achieved impressive performance on several different datasets. However, their application still suffers from a generalizability issue because of insufficient data, especially for structure based models, as well as a heterogeneity problem because of different label measurements and varying proteins across datasets. Here, we present an interpretable multi-task model to evaluate protein-ligand interaction (Multi-PLI). The model can run classification (binding or not) and regression (binding affinity) tasks concurrently by unifying different datasets. The model outperforms traditional docking and machine learning on both binary classification and regression tasks and achieves competitive results compared with some structure-based deep learning methods, even with the same training set size. Furthermore, combined with the proposed occlusion algorithm, the model can predict the important amino acids of proteins that are crucial for binding, thus providing a biological interpretation.
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http://dx.doi.org/10.1186/s13321-021-00510-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8051026PMC
April 2021

Dual activation of Hedgehog and Wnt/β-catenin signaling pathway caused by downregulation of SUFU targeted by miRNA-150 in human gastric cancer.

Aging (Albany NY) 2021 Apr 12;13(7):10749-10769. Epub 2021 Apr 12.

Guangdong Key Laboratory for Genome Stability and Disease Prevention, Department of Pathology, Shenzhen University School of Medicine, Shenzhen 518060, Guangdong, P.R. China.

Mounting evidence has shown that miRNA-150 expression is upregulated in gastric cancer (GC) and is associated with gastric carcinogenesis, but the underlying oncogenic mechanism remains elusive. Here, we discovered that miRNA-150 targets the tumor suppressor SUFU to promote cell proliferation, migration, and the epithelial-mesenchymal transition (EMT) via the dual activation of Hedgehog (Hh) and Wnt signaling. MiRNA-150 was highly expressed in GC tissues and cell lines, and the level of this miRNA was negatively related to that of SUFU. In addition, both the miRNA-150 and SUFU levels were associated with tumor differentiation. Furthermore, miRNA-150 activated GC cell proliferation and migration . We found that miRNA-150 inhibitors repressed not only Wnt signaling by promoting cytoplasmic β-catenin localization, but also repressed Hh signaling and EMT. MiRNA-150 inhibition also resulted in significant tumor volume reductions , suggesting the potential application of miRNA-150 inhibitors in GC therapy. The expression of genes downstream of Hh and Wnt signaling was also reduced in tumors treated with miRNA-150 inhibitors. Notably, anti-SUFU siRNAs rescued the inhibitory effects of miRNA-150 inhibitors on Wnt signaling, Hh activation, EMT, cell proliferation, cell migration, and colony formation. Taken together, these findings indicate that miRNA-150 is oncogenic and promotes GC cell proliferation, migration, and EMT by activating Wnt and Hh signaling via the suppression of SUFU expression.
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http://dx.doi.org/10.18632/aging.202895DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8064165PMC
April 2021

Three-dimensional nanolithography guided by DNA modular epitaxy.

Nat Mater 2021 May 12;20(5):683-690. Epub 2021 Apr 12.

Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA, USA.

Lithographic scaling of periodic three-dimensional patterns is critical for advancing scalable nanomanufacturing. Current state-of-the-art quadruple patterning or extreme-ultraviolet lithography produce a line pitch down to around 30 nm, which might be further scaled to sub-20 nm through complex post-fabrication processes. Herein, we report the use of three-dimensional (3D) DNA nanostructures to scale the line pitch down to 16.2 nm, around 50% smaller than state-of-the-art results. We use a DNA modular epitaxy approach to fabricate 3D DNA masks with prescribed structural parameters (geometry, pitch and critical dimensions) along a designer assembly pathway. Single-run reactive ion etching then transfers the DNA patterns to a Si substrate at a lateral critical dimension of 7 nm and a vertical critical dimension of 2 nm. The nanolithography guided by DNA modular epitaxy achieves a smaller pitch than the projected values for advanced technology nodes in field-effect transistors, and provides a potential complement to the existing lithographic tools for advanced 3D nanomanufacturing.
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http://dx.doi.org/10.1038/s41563-021-00930-7DOI Listing
May 2021

Harvesting of Rhodotorula glutinis via Polyaluminum Chloride or Cationic Polyacrylamide Using the Extended DLVO Theory.

Appl Biochem Biotechnol 2021 Apr 8. Epub 2021 Apr 8.

Beijing Key Lab of Bioprocess, National Energy R&D Center for Biorefinery, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.

Polyaluminum chloride (PAC) and cationic polyacrylamide (CPAM) play a crucial role for separating microorganisms from bulk media. However, the mechanism of adsorption between cells and flocculants remain to be further defined to improve the flocculation efficiency (FE) in extreme conditions. This study conducted the flocculation process of Rhodotorula glutinis induced by PAC and CPAM, firstly. The result demonstrated that CPAM possessed more efficient harvesting ability for R. glutinis compared to PAC. The difference of flocculation capacity was then thermodynamically explained by the extended DLVO (eDLVO) theory; it turned out that the poor harvesting efficiency of PAC was attributed to lacking of binding sites as well as low adsorption force within particles. Based on this, the FE of PAC to R. glutinis was mechanically enhanced to 99.84% from 32.89% with 0.2 g/L CPAM modification at an optimum pH of 9. Also, the paper will play a guiding role in the treatment of inorganic salt ions and organic matters in wastewater.
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http://dx.doi.org/10.1007/s12010-021-03549-1DOI Listing
April 2021

Beating Standard Quantum Limit with Weak Measurement.

Entropy (Basel) 2021 Mar 16;23(3). Epub 2021 Mar 16.

CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China.

Weak measurements have been under intensive investigation in both experiment and theory. Numerous experiments have indicated that the amplified meter shift is produced by the post-selection, yielding an improved precision compared to conventional methods. However, this amplification effect comes at the cost of a reduced rate of acquiring data, which leads to an increasing uncertainty to determine the level of meter shift. From this point of view, a number of theoretical works have suggested that weak measurements cannot improve the precision, or even damage the metrology information due to the post-selection. In this review, we give a comprehensive analysis of the weak measurements to justify their positive effect on prompting measurement precision. As a further step, we introduce two modified weak measurement protocols to boost the precision beyond the standard quantum limit. Compared to previous works beating the standard quantum limit, these protocols are free of using entangled or squeezed states. The achieved precision outperforms that of the conventional method by two orders of magnitude and attains a practical Heisenberg scaling up to n=106 photons.
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http://dx.doi.org/10.3390/e23030354DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8002236PMC
March 2021

Posterior thoracolumbar hemivertebra resection and short-segment fusion in congenital scoliosis: surgical outcomes and complications with more than 5-year follow-up.

BMC Surg 2021 Mar 25;21(1):165. Epub 2021 Mar 25.

Department of Orthopedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, 8 Gong Ti Nan Lu, Chaoyang District, Beijing, 100020, China.

Background: Treatment of congenital hemivertebra is challenging and data on long-term follow-up (≥ 5 years) are lacking. This study evaluated the surgical outcomes of posterior thoracolumbar hemivertebra resection and short-segment fusion with pedicle screw fixation for treatment of congenital scoliosis with over 5-year follow-up.

Methods: This study evaluated 27 consecutive patients with congenital scoliosis who underwent posterior thoracolumbar hemivertebra resection and short-segment fusion from January 2007 to January 2015. Segmental scoliosis, total main scoliosis, compensatory cranial curve, compensatory caudal curve, trunk shift, shoulder balance, segmental kyphosis, and sagittal balance were measured on radiographs. Radiographic outcomes and all intraoperative and postoperative complications were recorded.

Results: The segmental main curve was 40.35° preoperatively, 11.94° postoperatively, and 13.24° at final follow-up, with an average correction of 65.9%. The total main curve was 43.39° preoperatively, 14.13° postoperatively, and 16.06° at final follow-up, with an average correction of 60.2%. The caudal and cranial compensatory curves were corrected from 15.78° and 13.21° to 3.57° and 6.83° postoperatively and 4.38° and 7.65° at final follow-up, with an average correction of 69.2% and 30.3%, respectively. The segmental kyphosis was corrected from 34.30° to 15.88° postoperatively and 15.12° at final follow-up, with an average correction of 61.9%. A significant correction (p < 0.001) in segmental scoliosis, total main curve, caudal compensatory curves and segmental kyphosis was observed from preoperative to the final follow-up. The correction in the compensatory cranial curve was significant between preoperative and postoperative and 2-year follow-up (p < 0.001), but a statistically significant difference was not observed between the preoperative and final follow-up (p > 0.001). There were two implant migrations, two postoperative curve progressions, five cases of proximal junctional kyphosis, and four cases of adding-on phenomena.

Conclusion: Posterior thoracolumbar hemivertebra resection after short-segment fusion with pedicle screw fixation in congenital scoliosis is a safe and effective method for treatment and can achieve rigid fixation and deformity correction.
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http://dx.doi.org/10.1186/s12893-021-01165-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7993516PMC
March 2021

Research on obstacle avoidance algorithm for unmanned ground vehicle based on multi-sensor information fusion.

Math Biosci Eng 2021 01;18(2):1022-1039

School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou 510640, China.

With the wide application of unmanned ground vehicles (UGV) in a complex environment, the research on the obstacle avoidance system has gradually become an important research part in the field of the UGV system. Aiming at the complex working environment, a sensor detection system mounted on UGV is designed and the kinematic estimation model of UGV is studied. In order to meet the obstacle avoidance requirements of UGVs in a complex environment, a fuzzy neural network obstacle avoidance algorithm based on multi-sensor information fusion is designed in this paper. MATLAB is used to simulate the obstacle avoidance algorithm. By comparing and analyzing the simulation path of UGV's obstacle avoidance motion under the navigation control of fuzzy controller and fuzzy neural network algorithm, the superiority of the proposed fuzzy neural network algorithm was verified. Finally, the superiority and reliability of the obstacle avoidance algorithm are verified through the obstacle avoidance experiment on the UGV experimental platform.
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http://dx.doi.org/10.3934/mbe.2021055DOI Listing
January 2021

Development of a Reduced Chemical Reaction Mechanism for -Pentanol Based on Combined Reduction Methods and Genetic Algorithm.

ACS Omega 2021 Mar 26;6(9):6448-6459. Epub 2021 Feb 26.

Key Laboratory of Shaanxi Province for Development and Application of New Transportation Energy, Chang'an University, Xi'an 710064, P. R. China.

To gradually reduce the demand for fossil energy and accelerate energy transformation, alcohol fuels are being vigorously developed and utilized in the world. -Pentanol as a common alcohol fuel has attracted increasing attention in recent years owing to its many advantages. In this study, a reduced mechanism of -pentanol containing 148 species and 575 reactions was established based on combined reduction methods including the direct relationship graph with error propagation, reaction pathway analysis, rate of production analysis, and temperature sensitivity analysis methods. Then, the reaction rate parameters were optimized using the nondominated sorting genetic algorithm II. A verification experiment for the oxidation of -pentanol was conducted in a jet-stirred reactor (JSR) with gas chromatography-mass spectrometry. The main species mole fractions were quantitatively analyzed in the temperature range 700-1100 K, equivalence ratios of 0.5-2.0, and a pressure of 1 atm. Extensive validations were performed over wide experimental conditions by comparing the experimental data of the ignition delay time, species concentration profiles in the JSR, and laminar flame speed. It was found that the predicted values were in good agreement with the experimental values. Therefore, the reduced mechanism developed in this study can accurately predict the experimental results, which is capable of reasonably applying to the simulation of combustion behaviors of -pentanol in internal combustion engines.
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http://dx.doi.org/10.1021/acsomega.1c00147DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7948435PMC
March 2021

Punicalin Ameliorates Cell Pyroptosis Induced by LPS/ATP Through Suppression of ROS/NLRP3 Pathway.

J Inflamm Res 2021 5;14:711-718. Epub 2021 Mar 5.

Department of Veterinary Medicine, Beijing University of Agriculture, Beijing, 102206, People's Republic of China.

Purpose: Inflammation is the driving force of many inflammatory and autoimmune diseases, Pyroptosis is a process of cell death in response to excessive inflammation. Punicalin has been reported to have anti-inflammatory effects. However, the anti-pyroptosis is unknown. Hence, this study was aimed to research the inhibition of MG on LPS/ATP-induced pyroptosis in vitro.

Methods: Lipopolysaccharide (LPS)/ATP were used to simulate mouse J774A.1 cells to mimic the inflammatory response and the role of punicalin was examined. The secretion of proinflammatory cytokines was analyzed using enzyme-linked immunosorbent assay (ELISA). The expression of nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3), apoptosis-associated speck-like protein containing a caspase activation and recruitment domain (ASC), caspase-1, and GSDMD-N in LPS/ATP-stimulated cells were examined by Western blot. N-acetylcysteine (NAC) was used to validate the role of Punicalin.

Results: Punicalin significantly blocked the production of endogenous ROS, reduced LPS/ATP-induced activation of NLRP3, caspase 1, ASC and GSDMD-N, IL-1b and IL-18 protein levels. Furthermore, N-acetylcysteine (NAC), an ROS scavenger, inhibited the LPS/ATP-stimulated activation of NLRP3 inflammasome mediated inflammation and pyroptosis.

Conclusion: Punicalin ameliorates LPS/ATP-induced pyroptosis in J774A.1 macrophages, the mechanism may involve downregulation of the ROS/NLRP3 inflammasome signaling pathway.
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http://dx.doi.org/10.2147/JIR.S299163DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7943540PMC
March 2021

Ambient nitrogen dioxide and years of life lost from chronic obstructive pulmonary disease in the elderly: A multicity study in China.

Chemosphere 2021 Jul 20;275:130041. Epub 2021 Feb 20.

Department of Occupational and Environmental Health Sciences, Peking University School of Public Health, Beijing, China. Electronic address:

Background: Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide, and nitrogen dioxide (NO) is a potential environmental risk factor for COPD. However, association between ambient NO and COPD risk remains underrecognized, especially in the elderly. This study aimed to explore association between NO and years of life lost (YLL) from COPD in the elderly from 2013 to 2017 in 37 major cities in China.

Methods: Ambient NO data and COPD morality information were obtained from the National Urban Air Quality Real-time Publishing Platform and the Chinese Centers for Disease Control and Prevention, respectively. City-specific relative changes in YLL were estimated by generalized additive models, and meta-analysis was used to combine city-specific results. Potential modifications were evaluated. Economic loss due to excess YLL from COPD associated with ambient NO was evaluated.

Results: An increase of 10 μg/m in NO for 2-day moving average led to 0.94% (95% CI: 0.56%, 1.31%) relative increase in COPD YLL. The associations were significantly higher in South than North China. Higher estimated effects were found in the warm than the cool season in the southern region. The relevant economic loss accounted for 0.04% (95% CI: 0.02%, 0.05%) of the gross domestic product (GDP) in China during the same period.

Conclusions: The findings provide evidence on the impact of short-term NO exposure on COPD YLL in the elderly, which indicated more stringent control of NO pollution and highlighted the need to protect the elderly during the warm season in South China.
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http://dx.doi.org/10.1016/j.chemosphere.2021.130041DOI Listing
July 2021

Simultaneous sensing of cysteine/homocysteine and glutathione with a fluorescent probe based on a single atom replacement strategy.

Anal Methods 2021 03 26;13(11):1358-1363. Epub 2021 Feb 26.

Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha 410081, China.

In recent years, there have been many reports of fluorescent probes for multi-channel detection of Cys, Hcy and GSH. Particularly, reports of fluorescent probes using NBD (7-nitro-1,2,3-benzoxadiazole) or SNBD (7-nitro-1,2,3-benzothiadiazole) moieties as fluorophores are particularly common. Unfortunately, their 4-sulfhydryl derivatives exhibited negligible fluorescence, which makes them incapable of detecting GSH directly. Herein, by performing single selenium-for-oxygen atom replacement within 4-chloro-substituted NBD (NBD-Cl), we developed a small molecule fluorescent probe based on a single atom replacement strategy, which enables the probe to be used for simultaneously distinguishing Cys/Hcy and GSH, along with fluorescence imaging of Cys/Hcy and GSH in live cells from red and green emission channels, respectively.
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http://dx.doi.org/10.1039/d0ay02206cDOI Listing
March 2021

Excess mortality in Wuhan city and other parts of China during the three months of the covid-19 outbreak: findings from nationwide mortality registries.

BMJ 2021 02 24;372:n415. Epub 2021 Feb 24.

The National Center for Chronic and Non-communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention (China CDC), Xicheng District, 100050, Beijing, China

Objective: To assess excess all cause and cause specific mortality during the three months (1 January to 31 March 2020) of the coronavirus disease 2019 (covid-19) outbreak in Wuhan city and other parts of China.

Design: Nationwide mortality registries.

Setting: 605 urban districts and rural counties in China's nationally representative Disease Surveillance Point (DSP) system.

Participants: More than 300 million people of all ages.

Main Outcome Measures: Observed overall and weekly mortality rates from all cause and cause specific diseases for three months (1 January to 31 March 2020) of the covid-19 outbreak compared with the predicted (or mean rates for 2015-19) in different areas to yield rate ratio.

Results: The DSP system recorded 580 819 deaths from January to March 2020. In Wuhan DSP districts (n=3), the observed total mortality rate was 56% (rate ratio 1.56, 95% confidence interval 1.33 to 1.87) higher than the predicted rate (1147 735 per 100 000), chiefly as a result of an eightfold increase in deaths from pneumonia (n=1682; 275 33 per 100 000; 8.32, 5.19 to 17.02), mainly covid-19 related, but a more modest increase in deaths from certain other diseases, including cardiovascular disease (n=2347; 408 316 per 100 000; 1.29, 1.05 to 1.65) and diabetes (n=262; 46 25 per 100 000; 1.83, 1.08 to 4.37). In Wuhan city (n=13 districts), 5954 additional (4573 pneumonia) deaths occurred in 2020 compared with 2019, with excess risks greater in central than in suburban districts (50% 15%). In other parts of Hubei province (n=19 DSP areas), the observed mortality rates from pneumonia and chronic respiratory diseases were non-significantly 28% and 23% lower than the predicted rates, despite excess deaths from covid-19 related pneumonia. Outside Hubei (n=583 DSP areas), the observed total mortality rate was non-significantly lower than the predicted rate (675 715 per 100 000), with significantly lower death rates from pneumonia (0.53, 0.46 to 0.63), chronic respiratory diseases (0.82, 0.71 to 0.96), and road traffic incidents (0.77, 0.68 to 0.88).

Conclusions: Except in Wuhan, no increase in overall mortality was found during the three months of the covid-19 outbreak in other parts of China. The lower death rates from certain non-covid-19 related diseases might be attributable to the associated behaviour changes during lockdown.
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http://dx.doi.org/10.1136/bmj.n415DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7900645PMC
February 2021

Turn-on fluorescent probe for sensing exogenous and endogenous hypochlorous acid in living cells, zebrafishes and mice.

Talanta 2021 Apr 28;225:122030. Epub 2020 Dec 28.

Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research (Ministry of Education), College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, 410081, China. Electronic address:

Hypochlorous acid (HOCl), belonging to biologically significant reactive oxygen species (ROS), plays crucial roles in many biological and pathological processes. It is of great value to explore fluorescent probes for the image of hypochlorous acid in various biological environments. We herein reported a novel fluorescent probe HN-ClO for monitoring HOCl with moderate water-solubility, good photostability, high fluorescence quantum yield and large Stokes shift. This probe exhibited excellent selectivity and high sensitivity to sense HOCl. Furthermore, probe HN-ClO was successfully applied to monitor endogenous and exogenous HOCl in living cells, zebrafishes and mice, and possessed the potential to further explore the physiological and pathological roles of hypochlorous acid in biological systems.
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http://dx.doi.org/10.1016/j.talanta.2020.122030DOI Listing
April 2021

Projecting heat-related excess mortality under climate change scenarios in China.

Nat Commun 2021 02 15;12(1):1039. Epub 2021 Feb 15.

State Key Laboratory of Infectious Disease Prevention and Control, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, China.

Recent studies have reported a variety of health consequences of climate change. However, the vulnerability of individuals and cities to climate change remains to be evaluated. We project the excess cause-, age-, region-, and education-specific mortality attributable to future high temperatures in 161 Chinese districts/counties using 28 global climate models (GCMs) under two representative concentration pathways (RCPs). To assess the influence of population ageing on the projection of future heat-related mortality, we further project the age-specific effect estimates under five shared socioeconomic pathways (SSPs). Heat-related excess mortality is projected to increase from 1.9% (95% eCI: 0.2-3.3%) in the 2010s to 2.4% (0.4-4.1%) in the 2030 s and 5.5% (0.5-9.9%) in the 2090 s under RCP8.5, with corresponding relative changes of 0.5% (0.0-1.2%) and 3.6% (-0.5-7.5%). The projected slopes are steeper in southern, eastern, central and northern China. People with cardiorespiratory diseases, females, the elderly and those with low educational attainment could be more affected. Population ageing amplifies future heat-related excess deaths 2.3- to 5.8-fold under different SSPs, particularly for the northeast region. Our findings can help guide public health responses to ameliorate the risk of climate change.
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http://dx.doi.org/10.1038/s41467-021-21305-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7884743PMC
February 2021

3D-printed drill guide template, a promising tool to improve pedicle screw placement accuracy in spinal deformity surgery: A systematic review and meta-analysis.

Eur Spine J 2021 Feb 8. Epub 2021 Feb 8.

Department of Orthopedic Surgery, Beijing Chaoyang Hospital, Capital Medical University, GongTiNanLu 8#, Chaoyang District, Beijing, 100020, China.

Purpose: This study aimed to compare the pedicle screw placement accuracy and surgical outcomes between 3D-printed (3DP) drill guide template technique and freehand technique in spinal deformity surgery.

Methods: A comprehensive systematic literature search of databases (PubMed, Embase, Cochrane Library, and Web of Science) was conducted. The meta-analysis compared the pedicle screw placement accuracy and other important surgical outcomes between the two techniques.

Results: A total of seven studies were included in the meta-analysis, comprising 87 patients with 1384 pedicle screws placed by 3DP drill guide templates and 88 patients with 1392 pedicle screws placed by freehand technique. The meta-analysis results revealed that the 3DP template technique was significantly more accurate than the freehand technique to place pedicle screws and had a higher rate of excellently placed screws (OR 2.22, P < 0.001) and qualifiedly placed screws (OR 3.66, P < 0.001), and a lower rate of poorly placed screws (OR 0.23, P < 0.001). The mean placement time per screw (WMD-1.99, P < 0.05), total screw placement time (WMD-27.86, P < 0.001), and blood loss (WMD-104.58, P < 0.05) were significantly reduced in the 3DP template group compared with the freehand group. Moreover, there was no significant statistical difference between the two techniques in terms of the operation time and correction rate of main bend curve.

Conclusions: This study demonstrated that the 3DP drill guide template was a promising tool for assisting the pedicle screw placement in spinal deformity surgery and deserved further promotion.
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http://dx.doi.org/10.1007/s00586-021-06739-xDOI Listing
February 2021

Effects of Chinese wolfberry and Astragalus extract on the antioxidant capacity of Tibetan pig liver.

PLoS One 2021 27;16(1):e0245749. Epub 2021 Jan 27.

Institute of Microbiology Chinese Academy of Sciences, Beijing, China.

The objective of this study is to determine the effect of Chinese wolfberry (Lycium barbarum) and Astragalus (Astragalus membranaceus) extract (WAE) on the antioxidant capacity of Tibetan pig liver, and discussed the regulatory effect of WAE on the liver antioxidant mechanism. Twelve healthy 120-day-old Tibetan black pigs (35±2 kg) were divided randomly into two groups. The WAE group was fed a basal diet supplemented with 1% WAE for 90 days. The control group was fed the same diet, but without the WAE. We found that liver superoxide dismutase 1 (SOD1) activity (P<0.05), total antioxidative capacity (T-AOC) (P<0.05), and catalase (CAT) activity (P<0.01) significantly increased in the WAE group compared with the control group; malondialdehyde (MDA) content decreased, but this was not significant (P >0.05). Transcriptome sequencing analysis detected 106 differentially expressed genes (DEGs) related to oxidative stress. GO enrichment analysis showed these DEGs were involved in the positive regulation of reactive oxygen metabolism and biosynthesis, process regulation, and regulation of the oxidative stress response. KEGG Pathway enrichment analysis showed they were enriched in the PI3K-Akt, AMPK, Rap1, and peroxisome signaling pathways. The expression levels of key peroxisome biosynthesis genes (e.g., PEX3 and PEX11B) and key antioxidant genes (e.g., CAT and SOD1) were significantly higher in the WAE group than in the control group. The PRDX1 and PRDX5 content also was significantly higher in the WAE group. This study showed that the WAE regulated the antioxidant and anti-stress ability of Tibetan pig liver through a "peroxisome antioxidant-oxidant stress" signaling pathway.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0245749PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7840052PMC
January 2021

Broadband Nonlinear Photonics in Few-Layer Borophene.

Small 2021 Feb 27;17(7):e2006891. Epub 2021 Jan 27.

Institute of Microscale Optoelectronics, Collaborative Innovation Centre for Optoelectronic Science & Technology, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic Engineering, Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology, Guangdong Laboratory of Artificial Intelligence and Digital Economy (SZ), Shenzhen University, Shenzhen, 518060, P. R. China.

In this paper, 2D borophene is synthesized through a liquid-phase exfoliation. The morphology and structure of as-prepared borophene are systemically analyzed, and the Z-scan is used to measure the nonlinear optical properties. It is found that the saturable absorber (SA) properties of borophene make it serve as an excellent broadband optical switch, which is strongly used for mode-locking in near- and mid-infrared laser systems. Ultrastable pulses with durations as short as 792 and 693 fs are successfully delivered at the central wavelengths of 1063 and 1560 nm, respectively. Furthermore, stable pulses at a wavelength of 1878 nm are demonstrated from a thulium mode-locked fiber laser based on the same borophene SA. This research reveals a significant potential for borophene used in lasers helping extending the frontiers of photonic technologies.
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http://dx.doi.org/10.1002/smll.202006891DOI Listing
February 2021

Effects of an industrial passive assistive exoskeleton on muscle activity, oxygen consumption and subjective responses during lifting tasks.

PLoS One 2021 20;16(1):e0245629. Epub 2021 Jan 20.

School of Mechanical and Automotive Engineering, South China University of Technology, Guangzhou, China.

The purpose of this study was to evaluate the effects of an industrial passive assisted exoskeleton (IPAE) with simulated lifting tasks on muscle activity, oxygen consumption, perceived level of exertion, local perceived pressure, and systemic usability. Eight workers were required to complete two lifting tasks with and without the IPAE, that were single lifting tasks (repeated 5 times) and 15 min repeated lifting tasks respectively. Both of the tasks required subjects to remove a toolbox from the ground to the waist height. The test results showed that IPAE significantly reduced the muscle activity of the lumbar erector spinae, thoracic erector spinae, middle deltoid and labrum-biceps muscles; the reduction effect during the 15 min lifting task was reached 21%, 12%, 32% and 38% respectively. The exoskeleton did not cause significant differences in oxygen consumption and the perceived level of exertion, but local perceived pressure on the shoulders, thighs, wrists, and waist of the subjects could be produced. 50% of the subjects rated the usability of the equipment as acceptable. The results illustrate the good potential of the exoskeleton to reduce the muscle activity of the low back and upper arms. However, there is still a concern for the obvious contact pressure.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0245629PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7816984PMC
January 2021

Integration of Human Umbilical Cord Mesenchymal Stem Cells-Derived Exosomes with Hydroxyapatite-Embedded Hyaluronic Acid-Alginate Hydrogel for Bone Regeneration.

ACS Biomater Sci Eng 2020 03 18;6(3):1590-1602. Epub 2020 Feb 18.

Department of Stomatology, Chinese PLA General Hospital, Beijing 100853, China.

The treatment of bone defects has plagued clinicians. Exosomes, the naturally secreted nanovesicles by cells, exhibit great potential in bone defect regeneration to realize cell-free therapy. In this work, we successfully revealed that human umbilical cord mesenchymal stem cells-derived exosomes could effectively promote the proliferation, migration, and osteogenic differentiation of a murine calvariae preosteoblast cell line in vitro. Considering the long period of bone regeneration, to effectively exert the reparative effect of exosomes, we synthesized an injectable hydroxyapatite (HAP)-embedded in situ cross-linked hyaluronic acid-alginate (HA-ALG) hydrogel system to durably retain exosomes at the defect sites. Then, we combined the exosomes with the HAP-embedded in situ cross-linked HA-ALG hydrogel system to repair bone defects in rats in vivo. The results showed that the combination of exosomes and composite hydrogel could significantly enhance bone regeneration. Our experiment provides a new strategy for exosome-based therapy, which shows great potential in future tissue and organ repair.
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http://dx.doi.org/10.1021/acsbiomaterials.9b01363DOI Listing
March 2020

The impact of carbon monoxide on years of life lost and modified effect by individual- and city-level characteristics: Evidence from a nationwide time-series study in China.

Ecotoxicol Environ Saf 2021 Mar 8;210:111884. Epub 2021 Jan 8.

Department of Anesthesiology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. Electronic address:

Ambient carbon monoxide (CO) has been linked with mortality and morbidity. Little evidence is available regarding the relation between CO and years of life lost (YLL). Using data from 48 major cities in China from 2013 to 2017, we applied generalized additive models and random effects meta-analyses to explore the effects of CO on YLL from various diseases. Stratified analyses and meta-regression were performed to estimate potential effect modifications of demographic factors, regions, meteorological factors, co-pollutants, urbanization rate, economic level and health service level. Additional life gains due to avoidable YLL under certain scenario were also evaluated. Results indicated that a 1-mg/m³ increase of CO concentrations (lagged over 0-3 d), was associated with 2.08% (95% confidence interval [CI], 1.35%, 2.80%), 2.35% (95% CI: 1.39%, 3.30%), 1.47% (95% CI: -0.01%, 2.93%), 2.28% (95% CI: 1.09%, 3.47%), 2.42% (95% CI: 1.31%, 3.54%), 2.09% (95% CI: 0.47%, 3.72%) increments in daily YLL from non-accidental causes, cardiovascular diseases, respiratory diseases, coronary heart disease, stroke and chronic obstructive pulmonary disease, respectively. These associations were robust to the adjustment of co-pollutants and varied substantially by geography and demographic characteristics. Associations were stronger in the elder people (≥65 years), females, population with low education attainment, and lived in south region, than younger people, males, high educated populations and those lived in north region. Moreover, the harmful impact of increasing CO concentration could be attenuated by city-level characteristics, including the growth of urbanization rate, gross domestic product (GDP), GDP per capita, number of hospital beds, doctors and hospitals. Finally, an estimated life of 0.081 (95% CI: -0.027, 0.190) years would be gained per deceased people if CO concentration could fall to 1 mg/m. In conclusions, this nationwide analysis showed significant associations between short-term CO exposure and cause-specific YLL. The heterogeneity of both individual- and city-level characteristics should be considered for relevant intervention. These findings may have significant public health implications for the reduction of CO-attributed disease burden in China.
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http://dx.doi.org/10.1016/j.ecoenv.2020.111884DOI Listing
March 2021

The treatment of the atrophic clavicular nonunion by double-plate fixation with autogenous cancellous bone graft: a prospective study.

J Orthop Surg Res 2021 Jan 7;16(1):22. Epub 2021 Jan 7.

Department of Orthopaedics, Beijing Chao-Yang Hospital, China Capital Medical University, Beijing, 100020, China.

Background: The objective of this study is to assess prospectively the effectiveness of double-plate fixation combined with autogenous cancellous bone graft in the treatment for the atrophic clavicular nonunion.

Methods: Between February 2013 and November 2017, a total of 12 patients with atrophic clavicular nonunion (mean age, 40.4 ± 9.0 years, range, 27-60 years) were treated by double-plate fixation with autogenous cancellous bone graft in our institute. The Constant Score System was used to evaluate the preoperative and final outcomes. The Short Form-36 (SF-36) outcome questionnaire was used to assess the final clinical results.

Results: All patients were followed-up, with the average follow-up of 34.7 ± 6.7 months (range, 24-48 months). The healing rate was 100% in our study. The mean time of bony union was 9 weeks (range, 8-10 weeks). One patient had a postoperative superficial infection, and the patient was cured by oral antibiotics and wound dressing. No implant-related complications (plate-screw loosening or breakage) were observed postoperatively. No vascular injury, neural impairment, or thoracic outlet syndrome was discovered preoperatively or postoperatively. There is a statistical significance between the preoperative and the postoperative constant scores (P < 0.05). All the patients were satisfied with their final clinical results by SF-36 outcome questionnaire. Average scores of the physical function and bodily pain components of the SF-36 were 94.2 ± 7.3 and 92.5 ± 5.8, respectively.

Conclusion: Our results presented that double-plate fixation with autogenous cancellous bone graft is an effective treatment for atrophic clavicular nonunion, especially for those with a significant bone defect.
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http://dx.doi.org/10.1186/s13018-020-02154-yDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7792052PMC
January 2021

Experimental Investigation of Quantum PT-Enhanced Sensor.

Phys Rev Lett 2020 Dec;125(24):240506

CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, 230026, China.

PT-symmetric theory is developed to extend quantum mechanics to a complex region, but it wins its great success first in classical systems, for example, optical waveguides and electric circuits, etc., because there are so many counterintuitive phenomena and striking applications, including unidirectional light transport, PT-enhanced sensors (one kind of exceptional-point-based sensor), and wireless power transfer. However, these phenomena and applications are mostly based on the ability to approach a PT-symmetric broken region, which makes it difficult to transfer them to the quantum regime, since the broken quantum PT-symmetric system has not been constructed effectively, until recently several methods have been raised. Here, we construct a quantum PT-symmetric system assisted by weak measurement, which can effectively transit from the unbroken region to the broken region. The full energy spectrum including the real and imaginary parts is directly measured using weak values. Furthermore, based on the ability of approaching a broken region, we for the first time translate the previously mentioned PT-enhanced sensor into the quantum version, and investigate its various features that are associated to the optimal conditions for sensitivity enhancement. In this experiment, we obtain an enhancement of 8.856 times over the conventional Hermitian sensor. Moreover, by separately detecting the real and imaginary parts of energy splitting, we can derive the additional information of the direction of perturbations. Our work paves the way of leading classical interesting PT phenomena and applications to their quantum counterparts. More generally, since the PT system is a subset of non-Hermitian systems, our work will be also helpful in the studies of general exception point in the quantum regime.
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http://dx.doi.org/10.1103/PhysRevLett.125.240506DOI Listing
December 2020

A novel virtual screening procedure identifies Pralatrexate as inhibitor of SARS-CoV-2 RdRp and it reduces viral replication in vitro.

PLoS Comput Biol 2020 12 31;16(12):e1008489. Epub 2020 Dec 31.

Center for High Performance Computing, Joint Engineering Research Center for Health Big Data Intelligent Analysis Technology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China.

The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus poses serious threats to the global public health and leads to worldwide crisis. No effective drug or vaccine is readily available. The viral RNA-dependent RNA polymerase (RdRp) is a promising therapeutic target. A hybrid drug screening procedure was proposed and applied to identify potential drug candidates targeting RdRp from 1906 approved drugs. Among the four selected market available drug candidates, Pralatrexate and Azithromycin were confirmed to effectively inhibit SARS-CoV-2 replication in vitro with EC50 values of 0.008μM and 9.453 μM, respectively. For the first time, our study discovered that Pralatrexate is able to potently inhibit SARS-CoV-2 replication with a stronger inhibitory activity than Remdesivir within the same experimental conditions. The paper demonstrates the feasibility of fast and accurate anti-viral drug screening for inhibitors of SARS-CoV-2 and provides potential therapeutic agents against COVID-19.
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http://dx.doi.org/10.1371/journal.pcbi.1008489DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7774833PMC
December 2020

[Endogenous Pollution and Release Characteristics of Bottom Sediments of Hengshan Reservoir in Yixing City].

Huan Jing Ke Xue 2020 Dec;41(12):5400-5409

Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.

To clarify the endogenous pollution and release characteristics of the bottom sediment of Hengshan Reservoir in Yixing City, a typical section of the reservoir was sampled and analyzed. The research results show that the average concentrations of total nitrogen, total phosphorus, and organic matter in the surface sediments of Hengshan Reservoir are 2778 mg·kg, 899 mg·kg, and 3.1%, respectively. The endogenous pollution is serious, and the downstream sediments are highly polluted upstream of the reservoir. Phosphorus spectroscopic analysis results show that iron-bound phosphorus (Fe-P) and aluminum-bound phosphorus (Al-P) are the main bound phosphorus forms in the sediment, accounting for 28% and 39% of the total phosphorus, respectively. The average concentration of activated phosphorus in the sediment (combination of weakly adsorbed phosphorus, organic phosphorus, and iron phosphorus) is 255 mg·kg, accounting for 38% of the total phosphorus. The average release rates of nitrogen and phosphorus in sediments were 18.0 mg·(m·d) and 0.60 mg·(m·d). The correlation analysis results show that the organic matter content of the sediment is significantly correlated with the diffusion flux of phosphate, ammonia nitrogen, and ferrous iron (<0.05), indicating that the mineralization of organic matter in the sediment may be the main release source of nitrogen and phosphorus in the sediment influencing factors.
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http://dx.doi.org/10.13227/j.hjkx.202004253DOI Listing
December 2020