Publications by authors named "Yibo Zhao"

29 Publications

  • Page 1 of 1

Open-Door versus French-Door Laminoplasty for Patients with Multisegmental Cervical Spondylotic Myelopathy: A Systematic Review and Meta-analysis.

World Neurosurg 2021 Aug 21;155:82-93. Epub 2021 Aug 21.

Department of Orthopedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, China. Electronic address:

This study aimed to evaluate the superiority of open-door versus French-door posterior cervical laminoplasty in the treatment of multisegmental cervical spondylotic myelopathy by comparing the intraoperative parameters and clinical and radiologic outcomes of these 2 procedures. PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure, the Wanfang database, the Weipu database, and China Biology Medicine disk were searched. Articles were retrieved from database establishment through May 22, 2020. Data analysis was carried out on the retrieved articles using RevMan 5.3 software. This meta-analysis included 14 studies involving 1010 patients, among which 6 were randomized controlled trials and 8 were retrospective analyses. Comparing the open-door and French-door groups, no statistically significant differences were found in operative time (weighted mean difference [WMD] = -4.47, 95% CI [-17.85, 8.92], P = 0.51), postoperative Japanese Orthopaedic Association score (WMD= -0.24, 95% CI [-0.87, 0.38], P = 0.45), recovery rate (WMD= -0.58, 95% CI [-3.61, 2.45], P = 0.71), postoperative cervical lordosis (WMD= -0.15, 95% CI [-1.93, 1.63], P = 0.87), cervical range of motion (WMD = -3.04, 95% CI [-8.68, 2.59], P = 0.29), sagittal diameter of the spinal canal (WMD = -0.24, 95% CI [-0.54, 0.07], P = 0.13), incidence of C5 palsy (OR = 1.78, 95% CI [0.64, 4.93], P = 0.27), or incidence of cerebrospinal fluid leakage (OR = 1.51, 95% CI [0.48, 4.71], P = 0.48). However, the French-door group was associated with less intraoperative bleeding (WMD = 54.96, 95% CI [21.37, 88.55], P = 0.001) and a lower incidence of axial symptoms (OR = 2.50, 95% CI [1.32, 4.72], P = 0.005). This analysis suggests that both methods can achieve good postoperative outcomes. However, less intraoperative bleeding and a lower incidence of postoperative axial symptoms were found in the French-door group. This requires further validation and investigation in larger sample-size and well-designed randomized controlled studies.
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http://dx.doi.org/10.1016/j.wneu.2021.08.032DOI Listing
August 2021

Machine Learning-Enabled High-Resolution Dynamic Deuterium MR Spectroscopic Imaging.

IEEE Trans Med Imaging 2021 Jul 28;PP. Epub 2021 Jul 28.

Deuterium magnetic resonance spectroscopic imaging (DMRSI) has recently been recognized as a potentially powerful tool for noninvasive imaging of brain energy metabolism and tumor. However, the low sensitivity of DMRSI has significantly limited its utility for both research and clinical applications. This work presents a novel machine learning-based method to address this limitation. The proposed method synergistically integrates physics-based subspace modeling and data-driven deep learning for effective denoising, making high-resolution dynamic DMRSI possible. Specifically, a novel subspace model was used to represent the dynamic DMRSI signals; deep neural networks were trained to capture the low-dimensional manifolds of the spectral and temporal distributions of practical dynamic DMRSI data. The learned subspace and manifold structures were integrated via a regularization formulation to remove measurement noise. Theoretical analysis, computer simulations, and in vivo experiments have been conducted to demonstrate the denoising efficacy of the proposed method which enabled high-resolution imaging capability. The translational potential was demonstrated in tumor-bearing rats, where the Warburg effect associated with cancer metabolism and tumor heterogeneity were successfully captured. The new method may not only provide an effective tool to enhance the sensitivity of DMRSI for basic research and clinical applications but also provide a framework for denoising other spatiospectral data.
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http://dx.doi.org/10.1109/TMI.2021.3101149DOI Listing
July 2021

Accelerated Growth of Electrically Isolated Lithium Metal during Battery Cycling.

ACS Appl Mater Interfaces 2021 Aug 21;13(30):35750-35758. Epub 2021 Jul 21.

University of Michigan-Shanghai Jiao Tong University Joint Institute, Shanghai Jiao Tong University, Shanghai, 200240, China.

Severe capacity loss during cycling of lithium-metal batteries is one of the most concerning obstacles hindering their practical application. As this capacity loss is related to the variety of side reactions occurring to lithium metal, identification and quantification of these lithium-loss processes are extremely important. In this work, we systematically distinguish and quantify the different rates of lithium loss associated with galvanic corrosion, the formation of a solid-electrolyte interphase, and the formation of electrically isolated lithium metal (i.e., "dead" lithium). We show that the formation of "dead" Li is accelerated upon cycling, dominating the total lithium loss, with much slower rates of lithium loss associated with galvanic corrosion and formation of the solid-electrolyte interphase. Furthermore, photoacoustic imaging reveals that the three-dimensional spatial distribution of "dead" Li is distinctly different from that of freshly deposited lithium. This quantification is further extended to a solid-state Li/Cu cell based on a LiGePS solid-state electrolyte. The lithium loss in the solid-state cell is much severer than that of a conventional lithium-metal battery based on a liquid electrolyte. Our work highlights the importance of quantitative studies on conventional and solid-state lithium-metal batteries and provides a strong basis for the optimization of lithium-metal electrochemistry.
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http://dx.doi.org/10.1021/acsami.1c08944DOI Listing
August 2021

Improved estimation of myelin water fractions with learned parameter distributions.

Magn Reson Med 2021 Jul 3. Epub 2021 Jul 3.

Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.

Purpose: To improve estimation of myelin water fraction (MWF) in the brain from multi-echo gradient-echo imaging data.

Methods: A systematic sensitivity analysis was first conducted to characterize the conventional exponential models used for MWF estimation. A new estimation method was then proposed for improved estimation of MWF from practical gradient-echo imaging data. The proposed method uses an extended signal model that includes a finite impulse response filter to compensate for practical signal variations. This new model also enables the use of prelearned parameter distributions as well as low-rank signal structures to improve parameter estimation. The resulting parameter estimation problem was solved optimally in the Bayesian sense.

Results: Our sensitivity analysis results showed that the conventional exponential models were very sensitive to measurement noise and modeling errors. Our simulation and experimental results showed that our proposed method provided a substantial improvement in reliability, reproducibility, and robustness of MWF estimates over the conventional methods. Clinical results obtained from stroke patients indicated that the proposed method, with its improved capability, could reveal the loss of myelin in lesions, demonstrating its translational potentials.

Conclusion: This paper addressed the problem of robust MWF estimation from gradient-echo imaging data. A new method was proposed to provide improved MWF estimation in the presence of significant noise and modeling errors. The performance of the proposed method has been evaluated using both simulated and experimental data, showing significantly improved robustness over the existing methods. The proposed method may prove useful for quantitative myelin imaging in clinical applications.
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http://dx.doi.org/10.1002/mrm.28889DOI Listing
July 2021

Supplemental N-3 Polyunsaturated Fatty Acids Limit A1-Specific Astrocyte Polarization via Attenuating Mitochondrial Dysfunction in Ischemic Stroke in Mice.

Oxid Med Cell Longev 2021 9;2021:5524705. Epub 2021 Jun 9.

Department of Anesthesiology, Central People's Hospital of Zhanjiang, Zhanjiang, Guangdong 524045, China.

Ischemic stroke is one of the leading causes of death and disability for adults, which lacks effective treatments. Dietary intake of n-3 polyunsaturated fatty acids (n-3 PUFAs) exerts beneficial effects on ischemic stroke by attenuating neuron death and inflammation induced by microglial activation. However, the impact and mechanism of n-3 PUFAs on astrocyte function during stroke have not yet been well investigated. Our current study found that dietary n-3 PUFAs decreased the infarction volume and improved the neurofunction in the mice model of transient middle cerebral artery occlusion (tMCAO). Notably, n-3 PUFAs reduced the stroke-induced A1 astrocyte polarization both in vivo and in vitro. We have demonstrated that exogenous n-3 PUFAs attenuated mitochondrial oxidative stress and increased the mitophagy of astrocytes in the condition of hypoxia. Furthermore, we provided evidence that treatment with the mitochondrial-derived antioxidant, mito-TEMPO, abrogated the n-3 PUFA-mediated regulation of A1 astrocyte polarization upon hypoxia treatment. Together, this study highlighted that n-3 PUFAs prevent mitochondrial dysfunction, thereby limiting A1-specific astrocyte polarization and subsequently improving the neurological outcomes of mice with ischemic stroke.
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http://dx.doi.org/10.1155/2021/5524705DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8211499PMC
June 2021

The Hole-Tunneling Heterojunction of Hematite-Based Photoanodes Accelerates Photosynthetic Reaction.

Angew Chem Int Ed Engl 2021 Jul 9;60(29):16009-16018. Epub 2021 Jun 9.

State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China.

Single-atom metal-insulator-semiconductor (SMIS) heterojunctions based on Sn-doped Fe O nanorods (SF NRs) were designed by combining atomic deposition of an Al O overlayer with chemical grafting of a RuO hole-collector for efficient CO -to-syngas conversion. The RuO -Al O -SF photoanode with a 3.0 nm thick Al O overlayer gave a >5-fold-enhanced IPCE value of 52.0 % under 370 nm light irradiation at 1.2 V vs. Ag/AgCl, compared to the bare SF NRs. The dielectric field mediated the charge dynamics at the Al O /SF NRs interface. Accumulation of long-lived holes on the surface of the SF NRs photoabsorber aids fast tunneling transfer of hot holes to single-atom RuO species, accelerating the O -evolving reaction kinetics. The maximal CO-evolution rate of 265.3 mmol g  h was achieved by integration of double SIMS-3 photoanodes with a single-atom Ni-doped graphene CO -reduction-catalyst cathode; an overall quantum efficiency of 5.7 % was recorded under 450 nm light irradiation.
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http://dx.doi.org/10.1002/anie.202102983DOI Listing
July 2021

High-resolution sodium imaging using anatomical and sparsity constraints for denoising and recovery of novel features.

Magn Reson Med 2021 08 25;86(2):625-636. Epub 2021 Mar 25.

Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.

Purpose: To develop and evaluate a novel method for reconstruction of high-quality sodium MR images from noisy, limited k-space data.

Theory And Methods: A novel reconstruction method was developed for reconstruction of high-quality sodium images from noisy, limited k-space data. This method is based on a novel image model that contains a motion-compensated generalized series model and a sparse model. The motion-compensated generalized series model enables effective use of anatomical information from a proton image for denoising and resolution enhancement of sodium data, whereas the sparse model enables high-resolution reconstruction of sodium-dependent novel features. The underlying model estimation problems were solved efficiently using convex optimization algorithms.

Results: The proposed method has been evaluated using both simulation and experimental data obtained from phantoms, healthy human volunteers, and tumor patients. Results showed a substantial improvement in spatial resolution and SNR over state-of-the-art reconstruction methods, including compressed sensing and anatomically constrained reconstruction methods. Quantitative tissue sodium concentration maps were obtained from both healthy volunteers and brain tumor patients. These tissue sodium concentration maps showed improved lesion fidelity and allowed accurate interrogation of small targets.

Conclusion: A new method has been developed to obtain high-resolution sodium images with good SNR at 3 T. The proposed method makes effective use of anatomical prior information for denoising, while using a sparse model synergistically to recover sodium-dependent novel features. Experimental results have been obtained to demonstrate the feasibility of achieving high-quality tissue sodium concentration maps and their potential for improved detection of spatially heterogeneous responses of tumor to treatment.
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http://dx.doi.org/10.1002/mrm.28767DOI Listing
August 2021

Role of tranexamic acid in blood loss control and blood transfusion management of patients undergoing multilevel spine surgery: A meta-analysis.

Medicine (Baltimore) 2021 Feb;100(7):e24678

Department of Orthopedics, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, PR China.

Background: This study aimed to explore the role of tranexamic acid (TXA) in blood loss control and blood transfusion management of patients undergoing multilevel spine surgery.

Methods: In this meta-analysis, a comprehensive search of literatures was performed from PubMed, Embase, Cochrane Library, and Web of Science from inception to June 23rd, 2020. Weighed mean difference (WMD) was used as the effect size for measurement data, and risk ratio for enumeration data. Publication bias was assessed by Begg test.

Results: Totally 23 studies (11 randomized controlled trials and 12 cohort studies) involving 1621 participants were enrolled in this meta-analysis. The results showed that the administration of TXA can significantly decrease the intraoperative [WMD: -215.655, 95%CI: (-307.462, -123.847), P < .001], postoperative [WMD: -69.213, 95%CI: (-104.443, -33.983), P = .001] and total [WMD: -284.388, 95%CI: (-437.66, -131.116), P < .001] volumes of blood loss of patients undergoing multilevel spine surgery. It can also significantly reduce the intraoperative [WMD: -333.775, 95%CI: (-540.45, -127.099), P = .002] and postoperative [WMD: -114.661, 95%CI: (-219.58, -9.742), P = .032] volumes of transfusion. In addition, TXA was found to significantly increase the preoperative [WMD: 0.213, 95%CI: (0.037, 0.389), P = .018] and postoperative [WMD: 0.433, 95%CI: (0.244, 0.622), P < .001] hemoglobin levels as well as the preoperative platelet count [WMD: 14.069, 95%CI: (0.122, 28.015), P = .048].

Conclusion: The administration of TXA can effectively reduce blood loss and transfusion, and improve hemoglobin levels and preoperative platelet count in patients undergoing multilevel spine surgery.
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http://dx.doi.org/10.1097/MD.0000000000024678DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7899852PMC
February 2021

Fast high-resolution metabolic imaging of acute stroke with 3D magnetic resonance spectroscopy.

Brain 2020 12;143(11):3225-3233

High-Dimensional Neurology Group, Institute of Neurology, University College London, London, UK.

Impaired oxygen and cellular metabolism is a hallmark of ischaemic injury in acute stroke. Magnetic resonance spectroscopic imaging (MRSI) has long been recognized as a potentially powerful tool for non-invasive metabolic imaging. Nonetheless, long acquisition time, poor spatial resolution, and narrow coverage have limited its clinical application. Here we investigated the feasibility and potential clinical utility of rapid, high spatial resolution, near whole-brain 3D metabolic imaging based on a novel MRSI technology. In an 8-min scan, we simultaneously obtained 3D maps of N-acetylaspartate and lactate at a nominal spatial resolution of 2.0 × 3.0 × 3.0 mm3 with near whole-brain coverage from a cohort of 18 patients with acute ischaemic stroke. Serial structural and perfusion MRI was used to define detailed spatial maps of tissue-level outcomes against which high-resolution metabolic changes were evaluated. Within hypoperfused tissue, the lactate signal was higher in areas that ultimately infarcted compared with those that recovered (P < 0.0001). Both lactate (P < 0.0001) and N-acetylaspartate (P < 0.001) differed between infarcted and other regions. Within the areas of diffusion-weighted abnormality, lactate was lower where recovery was observed compared with elsewhere (P < 0.001). This feasibility study supports further investigation of fast high-resolution MRSI in acute stroke.
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http://dx.doi.org/10.1093/brain/awaa264DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7719019PMC
December 2020

Accelerating T mapping of the brain by integrating deep learning priors with low-rank and sparse modeling.

Magn Reson Med 2021 03 29;85(3):1455-1467. Epub 2020 Sep 29.

Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA.

Purpose: To accelerate T mapping with highly sparse sampling by integrating deep learning image priors with low-rank and sparse modeling.

Methods: The proposed method achieves high-speed T mapping by highly sparsely sampling (k, TE)-space. Image reconstruction from the undersampled data was done by exploiting the low-rank structure and sparsity in the T -weighted image sequence and image priors learned from training data. The image priors for a single TE were generated from the public Human Connectome Project data using a tissue-based deep learning method; the image priors were then transferred to other TEs using a generalized series-based method. With these image priors, the proposed reconstruction method used a low-rank model and a sparse model to capture subject-dependent novel features.

Results: The proposed method was evaluated using experimental data obtained from both healthy subjects and tumor patients using a turbo spin-echo sequence. High-quality T maps at the resolution of 0.9 × 0.9 × 3.0 mm were obtained successfully from highly undersampled data with an acceleration factor of 8. Compared with the existing compressed sensing-based methods, the proposed method produced significantly reduced reconstruction errors. Compared with the deep learning-based methods, the proposed method recovered novel features better.

Conclusion: This paper demonstrates the feasibility of learning T -weighted image priors for multiple TEs using tissue-based deep learning and generalized series-based learning. A new method was proposed to effectively integrate these image priors with low-rank and sparse modeling to reconstruct high-quality images from highly undersampled data. The proposed method will supplement other acquisition-based methods to achieve high-speed T mapping.
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http://dx.doi.org/10.1002/mrm.28526DOI Listing
March 2021

Simultaneous QSM and metabolic imaging of the brain using SPICE: Further improvements in data acquisition and processing.

Magn Reson Med 2021 02 18;85(2):970-977. Epub 2020 Aug 18.

Beckman Institute of Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois.

Purpose: To achieve high-resolution mapping of brain tissue susceptibility in simultaneous QSM and metabolic imaging.

Methods: Simultaneous QSM and metabolic imaging was first achieved using SPICE (spectroscopic imaging by exploiting spatiospectral correlation), but the QSM maps thus obtained were at relatively low-resolution (2.0 × 3.0 × 3.0 mm ). We overcome this limitation using an improved SPICE data acquisition method with the following novel features: 1) sampling (k, t)-space in dual densities, 2) sampling central k-space fully to achieve nominal spatial resolution of 3.0 × 3.0 × 3.0 mm for metabolic imaging, and 3) sampling outer k-space sparsely to achieve spatial resolution of 1.0 × 1.0 × 1.9 mm for QSM. To keep the scan time short, we acquired spatiospectral encodings in echo-planar spectroscopic imaging trajectories in central k-space but in CAIPIRINHA (controlled aliasing in parallel imaging results in higher acceleration) trajectories in outer k-space using blipped phase encodings. For data processing and image reconstruction, a union-of-subspaces model was used, effectively incorporating sensitivity encoding, spatial priors, and spectral priors of individual molecules.

Results: In vivo experiments were carried out to evaluate the feasibility and potential of the proposed method. In a 6-min scan, QSM maps at 1.0 × 1.0 × 1.9 mm resolution and metabolic maps at 3.0 × 3.0 × 3.0 mm nominal resolution were obtained simultaneously. Compared with the original method, the QSM maps obtained using the new method reveal fine-scale brain structures more clearly.

Conclusion: We demonstrated the feasibility of achieving high-resolution QSM simultaneously with metabolic imaging using a modified SPICE acquisition method. The improved capability of SPICE may further enhance its practical utility in brain mapping.
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http://dx.doi.org/10.1002/mrm.28459DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7722130PMC
February 2021

Accelerated J-resolved H-MRSI with limited and sparse sampling of ( -space.

Magn Reson Med 2021 01 29;85(1):30-41. Epub 2020 Jul 29.

Institute for Medical Imaging Technology, School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China.

Purpose: To accelerate the acquisition of J-resolved proton magnetic resonance spectroscopic imaging ( H-MRSI) data for high-resolution mapping of brain metabolites and neurotransmitters.

Methods: The proposed method used a subspace model to represent multidimensional spatiospectral functions, which significantly reduced the number of parameters to be determined from J-resolved H-MRSI data. A semi-LASER-based (Localization by Adiabatic SElective Refocusing) echo-planar spectroscopic imaging (EPSI) sequence was used for data acquisition. The proposed data acquisition scheme sampled -space in variable density, where t and t specify the J-coupling and chemical-shift encoding times, respectively. Selection of the J-coupling encoding times (or, echo time values) was based on a Cramer-Rao lower bound analysis, which were optimized for gamma-aminobutyric acid (GABA) detection. In image reconstruction, parameters of the subspace-based spatiospectral model were determined by solving a constrained optimization problem.

Results: Feasibility of the proposed method was evaluated using both simulated and experimental data from a spectroscopic phantom. The phantom experimental results showed that the proposed method, with a factor of 12 acceleration in data acquisition, could determine the distribution of J-coupled molecules with expected accuracy. In vivo study with healthy human subjects also showed that 3D maps of brain metabolites and neurotransmitters can be obtained with a nominal spatial resolution of 3.0 × 3.0 × 4.8 mm from J-resolved H-MRSI data acquired in 19.4 min.

Conclusions: This work demonstrated the feasibility of highly accelerated J-resolved H-MRSI using limited and sparse sampling of -space and subspace modeling. With further development, the proposed method may enable high-resolution mapping of brain metabolites and neurotransmitters in clinical applications.
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http://dx.doi.org/10.1002/mrm.28413DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7992196PMC
January 2021

Small molecule antagonist of C-C chemokine receptor 1 (CCR1) reduces disc inflammation in the rabbit model.

Spine J 2020 12 13;20(12):2025-2036. Epub 2020 Jul 13.

Department of Orthopedic Surgery, Rush University Medical Center, 1611 W Harrison Street, Suite 300, Chicago, IL 60612, USA. Electronic address:

Background Context: Targeting chemokines or chemokine receptors is a promising treatment strategy for diseases with chronic inflammation such as rheumatoid arthritis and discogenic pain. Identifying specific molecules and determining their effectiveness in animal models are the first steps in developing these treatments. Macrophage markers have been detected in the intervertebral disc tissues of patients with disc degenerative disease and discogenic pain and in different animal models. Macrophage recruitment into the disc may play a role in initiation of inflammation and if unresolved may lead to chronic inflammation and subsequent back pain.

Purpose: The objectives of these studies are to (1) identify chemokine receptor antagonists that can block macrophage migration induced by disc cells in vitro and (2) determine if intradiscal treatment with these antagonists can reduce disc inflammation and degeneration in vivo.

Study Design: In vitro migration assays were used to test effectiveness of chemokine receptor antagonists to block macrophage migration induced by disc cells. The rabbit annular puncture model was used to test for anti-inflammatory and regenerative effects of chemokine receptor antagonist treatment in vivo.

Methods: In vitro - THP-1 human monocytic cell line and freshly isolated rabbit primary splenocytes were assayed for migration using 3 µm Corning Transwell inserts with conditioned media of interleukin (IL)-1β treated human or rabbit disc cells. Inhibition of macrophage migration was evaluated using different concentrations of small molecule antagonists of C-C chemokine receptor (CCR)1 and CCR2. In vivo - New Zealand White rabbits (n=40) underwent disc puncture and intradiscal treatment with saline, CCR1 or CCR2 antagonists within the same procedure. X-ray and magnetic resonance (MR) images and serum samples were taken for disc height, MRI grade and IL-8 serum level analyses. Intervertebral discs were isolated for RNA analysis of inflammatory and disc phenotypic markers and for immunohistochemical analysis of macrophage marker, RAM11. The outcome measures were compared between the three treatment groups. These studies were funded by a research grant from AO Foundation, Switzerland (Project no S-14-86A; 120000 CHF). CCR1 and CCR2 antagonists were kindly provided by ChemoCentryx (Mountain View, CA).

Results: In vitro migration assays showed that THP-1 migration induced by disc cells was blocked by CCR2 antagonist more effectively than CCR1 antagonist, while rabbit splenocyte migration was inhibited by CCR1 antagonist and not the other. In the rabbit annular puncture model, rabbit discs treated with CCR1 antagonist had significantly better MRI grades than those treated with CCR2 antagonist at 6 weeks post-treatment. Gene expression studies demonstrate that discs treated with CCR1 or CCR2 antagonists expressed less inflammatory markers than saline-treated discs at 3 weeks post-treatment. Although CCR2 antagonist treatment did not reduce inflammatory marker expression at 6 weeks, discs treated with CCR1 antagonist expressed less inflammatory markers and also a higher ratio of collagen type 2 to collagen type 1 genes indicating favorable disc matrix production. There were no significant differences between all three treatment groups in regards to disc height indexes, IL-8 serum levels or macrophage marker detection.

Conclusions: These studies have identified that small molecule antagonists against CCR2 and CCR1 were respectively effective in blocking THP-1 and rabbit splenocyte migration induced by disc cells in vitro. Further, both CCR2 and CCR1 antagonist intradiscal treatments were effective in reducing disc inflammation at an early time point of 3 weeks. Lastly, only CCR1 antagonist demonstrated anti-inflammatory effects and better MRI grades at 6 weeks.

Clinical Significance: Our preclinical studies demonstrate that CCR1 and CCR2 antagonist delivery through intradiscal injection is sufficient to reduce disc inflammation at early time points, whereas CCR1 antagonists had longer term anti-inflammatory effects. Clinical studies have found that CCR1 antagonist was safe, tolerable and clinically active in reducing inflammation in rheumatoid arthritis patients. These studies suggest that CCR1 antagonist may be a promising biological treatment to reduce disc inflammation that translates to back pain relief.
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http://dx.doi.org/10.1016/j.spinee.2020.07.001DOI Listing
December 2020

Ultrastable and Durable Silicone Coating on Polycarbonate Surface Realized by Nanoscale Interfacial Engineering.

ACS Appl Mater Interfaces 2020 Mar 3;12(11):13296-13304. Epub 2020 Mar 3.

National Engineering Research Center for Advanced Polymer Processing Technology, Key Laboratory of Materials Processing and Mold, Zhengzhou University, Zhengzhou 450000, China.

Delamination of coating layer from polymer substrate limits the lifetime and functionality of the protective films. Silicone coating is especially vulnerable to photo irradiation, hydrothermal degradation, and mechanical deformation due to the low interfacial adhesion and mechanical robustness. Herein, an ingenious approach is developed to fabricate ultrastable and durable silicone coating on polycarbonate (PC) substrate through well-controlled nanoscale interfacial engineering. A nanopillar array is fabricated on the PC surface by vacuum-assisted hot embossing using anodic aluminum oxide (AAO) templates. Significant improvement in interfacial shear strength (ISS) is achieved for the silicone coating on the nanostructured PC surface. The delamination mechanism can be controlled by tuning the nanopillar size, and the maximum ISS of 9.9 MPa was reached on a surface with a nanopillar diameter of 320 nm. Attributed to the increased interfacial area and mechanical interlocking structure, the nanostructured interface can effectively dissipate interfacial stress and prevent cracking; therefore, maintaining excellent transparency and performance in the harsh environment. The coating exhibits extraordinary stability and durability when subjected to UV irradiation for 168 h, hydrothermal aging for 120 h, mechanical bending for 1000 cycles, and even surface damage. Thus, the tough silicone coating on polymer substrate realized by nanoscale interfacial engineering is a promising technique for highly stable and durable transparent surface protection.
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http://dx.doi.org/10.1021/acsami.9b22877DOI Listing
March 2020

Geographic distribution of heavy metals and identification of their sources in soils near large, open-pit coal mines using positive matrix factorization.

J Hazard Mater 2020 04 11;387:121666. Epub 2019 Nov 11.

School of Life Sciences, Qufu Normal University, Qufu, 273165, China.

Mining activities are considered the most important factor causing heavy metal accumulation in surface soil and it is important to understand the spatial distribution and source of heavy metals in typical steppes. In this study, the contents, spatial distribution, and sources of heavy metals were determined using geostatistical analyses, multivariate statistical analyses, and a positive matrix factorization (PMF) model using 152 soil samples collected from a grassland near the Sheng-Li coal base. The results shows that the mean concentration of heavy metals is low and does not threaten the quality of the local soil. However, the concentrations of eight heavy metals (Cu 15.04 mg kg, Zn 49.30 mg kg, Cd 0.11 mg kg, Pb 20.00 mg kg, Se 0.12 mg kg, Ge 1.45 mg kg, As 9.06 mg kg, and Sn 2.52 mg kg) are higher than their mean background values in soil in Inner Mongolia. High coefficients of variation for the heavy metals, especially Ge (1.03), and As (0.56), indicate that the concentrations of the elements are affected by the presence of the open-pit mines. Multivariate statistical and geo-statistical analyses show that Ge and As are highly correlated (R = 0.67, P < 0.01), suggesting that they have the same source. Using geostatistical and PMF models, we identified five potential pollution sources in the study area: 1) Industrial pollution (21.2 %), which includes smelting activity and open-pit coal mines, as suggested by elevated levels of Zn, Cd, Ge, and Cu; 2) Germanium mining (7.6 %), as indicated by higher levels of Ge and As; 3) Natural sources (37.2 %), as indicated by higher levels of Mn and Ni; 4) Coal mining activity (8.5 %), as indicated by higher levels of Sn and Cr; 5) Coal conveyor belts and high vehicular traffic, as indicated by elevated levels of Pb and Se. Taken together, the results of this study indicate that the coal base has a significant effect on the heavy metal concentration in the grassland. Therefore, the identification of the spatial distribution of heavy metals in the area may be key to controlling the pollution in the grassland. The results of this study can help to reduce pollution sources, cut down on pollution transport. So that zonal pollution control and ecological protection in the typical steppe region is achieved.
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http://dx.doi.org/10.1016/j.jhazmat.2019.121666DOI Listing
April 2020

Simultaneous metabolic and functional imaging of the brain using SPICE.

Magn Reson Med 2019 12 11;82(6):1993-2002. Epub 2019 Jul 11.

Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, Illinois.

Purpose: To enable simultaneous high-resolution mapping of brain function and metabolism.

Methods: An encoding scheme was designed for interleaved acquisition of functional MRI (fMRI) data in echo volume imaging trajectories and MR spectroscopic imaging (MRSI) data in echo-planar spectroscopic imaging trajectories. The scheme eliminates water and lipid suppression and utilizes free induction decay signals to encode both functional and metabolic information with ultrashort TE, short TR, and sparse sampling of -space. A subspace-based image reconstruction method was introduced for processing both the fMRI and MRSI data. The complementary information in the fMRI and MRSI data sets was also utilized to improve image reconstruction in the presence of intrascan head motion, field drift, and tissue susceptibility changes.

Results: In-vivo experimental results were obtained from healthy human subjects in resting-state fMRI/MRSI experiments. In these experiments, the proposed method was able to simultaneously acquire metabolic and functional information from the brain in high resolution. For scans of 6.5 minutes, we achieved 3.0 × 3.0 × 1.8 mm spatial resolution for fMRI, 1.9 × 2.5 × 3.0 mm nominal spatial resolution for MRSI, and 1.9 × 1.9 × 1.8 mm nominal spatial resolution for quantitative susceptibility maps.

Conclusion: This work demonstrates the feasibility of simultaneous high-resolution mapping of brain function and metabolism with improved spatial resolution and synergistic image reconstruction.
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http://dx.doi.org/10.1002/mrm.27865DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6717045PMC
December 2019

Differential Analysis of the Spinal Cord Shift After Laminoplasty With Upper Extension to the C2 Segment and Conventional Surgery of the C3-C7 Segments.

Clin Spine Surg 2020 03;33(2):E43-E49

Department of Orthopaedics, The Second Hospital of Shanxi Medical University, Taiyuan China.

Study Design: A retrospective controlled study.

Objective: To clarify the differences of spinal cord shift between laminoplasty with extension to the C2 segment and conventional surgery of the C3-C7 segments.

Summary Of Background Data: For patients of spinal cord compression at C2/C3 or C2, it is difficult to achieve decompression involving only the C3-C7 segments. Therefore, a laminoplasty with upper extension to C2 is needed. Nevertheless, there is not yet a definitive conclusion regarding whether laminoplasty with extension to C2 can achieve a better spinal cord shift than an extension of the C3-C7 segments.

Materials And Methods: Preoperative and final follow-up Japanese Orthopedic Association scores were recorded. MRI T2 patient images before and after surgery were used for data collection. The anterior subarachnoid spaces, spinal cord diameters, posterior subarachnoid spaces, and dural sac diameters were measured. The distance of spinal cord shift in a single plane was represented by the differences in the sum of the anterior subarachnoid spaces and the spinal cord diameters before and after surgery. The overall distances and distances of each segment backward were compared between the C2-C7 group and the C3-C7 group. All planes were also classified as segments with compression or noncompression, and the differences in backward shift were compared.

Results: There were no significant differences in Japanese Orthopedic Association score between the C2-C7 and C3-C7 groups at final follow-up and no significant differences in the overall backward shift between the 2 groups. The spinal cord shift of C1, C2, and C2/C3 segments and the segment of the largest shift distance were significantly different between the 2 groups; the spinal cord shift of the segments under compression was larger than that of noncompression.

Conclusions: Surgery with upper extension to the C2 segment did not increase the overall spinal cord shift; instead, a better effect was achieved by the effective decompression of local compressed segments, thus obtaining an effective expansion and shift of the spinal cord.

Levels Of Evidence: Level II.
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http://dx.doi.org/10.1097/BSD.0000000000000846DOI Listing
March 2020

Cadmium stress alters cytosine methylation status and expression of a select set of genes in Nicotiana benthamiana.

Plant Sci 2019 Jul 4;284:16-24. Epub 2019 Apr 4.

School of Life Science and Technology, Inner Mongolia University of Science and Technology, Baotou, 014010, China. Electronic address:

In this paper, we evaluated the genotoxicity of cadmium (Cd) in plants by performing a methylation-sensitive amplification polymorphism (MSAP) on the model plant Nicotiana benthamiana. Among 255 loci examined, 14 genes were found to show altered cytosine methylation patterns in response to Cd stress. Four of those genes (NbMORC3, NbHGSNAT, NbMUT, and NbBG) were selected for further analysis due to their predicted roles in plant development. Cd-induced changes of cytosine methylation status in MSAP fragments of selected genes were confirmed using bisulfite sequencing polymerase chain reaction (BSP). In addition, the expression levels of these genes were found to correlate with cadmium dosage, and a knock-down of these four genes via virus-induced genes silencing (VIGS) led to abnormal development and elevated sensitivity to cadmium stress. Silencing of these four genes resulted in altered cadmium accumulation in different parts of the experimental plants. Our data indicate that cadmium exposure causes dramatic changes in the cytosine methylation status of the plant genome, thus affecting the expression of many genes that are vital for plant growth and are involved in cadmium stress response.
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http://dx.doi.org/10.1016/j.plantsci.2019.03.021DOI Listing
July 2019

Self-assembled ruthenium (II) metallacycles and metallacages with imidazole-based ligands and their in vitro anticancer activity.

Proc Natl Acad Sci U S A 2019 03 14;116(10):4090-4098. Epub 2019 Feb 14.

Department of Chemistry, University of Utah, Salt Lake City, UT 84112;

Six tetranuclear rectangular metallacycles were synthesized via the [2+2] coordination-driven self-assembly of imidazole-based ditopic donor 1,4-bis(imidazole-1-yl)benzene and 1,3-bis(imidazol-1-yl)benzene, with dinuclear half-sandwich -cymene ruthenium(II) acceptors [Ru(µ-η-oxalato)(η--cymene)](SOCF), [Ru(µ-η-2,5-dioxido-1,4-benzoquinonato)(η--cymene)](SOCF) and [Ru(µ-η-5,8-dioxido-1,4-naphtoquinonato)(η--cymene)](SOCF), respectively. Likewise, three hexanuclear trigonal prismatic metallacages were prepared via the [2+3] self-assembly of tritopic donor of 1,3,5-tri(1-imidazol-1-yl)benzene with these ruthenium(II) acceptors respectively. Self-selection of the single symmetrical and stable metallacycle and cage was observed although there is the possibility of forming different conformational isomeric products due to different binding modes of these imidazole-based donors. The self-assembled macrocycles and cage containing the 5,8-dioxido-1,4-naphtoquinonato (donq) spacer exhibited good anticancer activity on all tested cancer cell lines (HCT-116, MDA-MB-231, MCF-7, HeLa, A549, and HepG-2), and showed decreased cytotoxicities in HBE and THLE-2 normal cells. The effect of Ru and imidazole moiety of these assemblies on the anticancer activity was discussed. The study of binding ability of these donq-based Ru assemblies with ctDNA indicated that the complex 9 with 180° linear 1 ligand has the highest bonding constant to ctDNA.
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http://dx.doi.org/10.1073/pnas.1818677116DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6410782PMC
March 2019

Template-Free Self-Assembly of Fluorine-Free Hydrophobic Polyimide Aerogels with Lotus or Petal Effect.

ACS Appl Mater Interfaces 2018 May 8;10(19):16901-16910. Epub 2018 May 8.

Suzhou Institute of Nano-Tech and Nano-Bionics , Chinese Academy of Sciences , Suzhou 215123 , P. R. China.

Aerogels have been widely used in the fields like thermal insulation, energy storage, environmental remediation, catalysis, drug release, sensor, and cosmic dust collection, etc. Hydrophobic functionalization not only determines the surface energy and basic physical properties of the target aerogels but also be critical for their long-term stability due to their highly open-porous structures. However, there is still lack of facial and versatile methodologies for the hydrophobic functionalization of aerogels, especially for the nonsilica ones. Herein, two efficient fluorine-free strategies were developed to synthesize various hydrophobic and even superhydrophobic polyimide (PI) aerogels. First, superhydrophobic PI aerogels with contact angle higher than 150° were fabricated by the segregation self-assembly process between poly[4,4'-(4,4'-isopropylidenediphenoxy)bis(phthalic anhydride)- co- p-phenylene diamine] and poly[biphenyl-3,3',3,4'-tetracarboxylic dianhydride- co-2,2'-dimethylbenzidine] (poly(BPDA-DMBZ)). These PI aerogels exhibited a lotus effect that water droplets could not wet the surface but could easily roll off. Second, various hydrophobic PI aerogels, including the well-documented superhydrophilic PI aerogels derived from DMBZ-BPDA and 4,4'-oxydianiline-BPDA, were synthesized by the density-induced hydrophilicity-hydrophobicity transition approach. These PI aerogels exhibited a petal effect that water droplets on the aerogel surface appeared spherical in shape, which could not roll off even when the aerogel was turned upside down. These two reported strategies might open new and straightforward ways to hydrophobic functionalization of other polymeric aerogel systems.
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http://dx.doi.org/10.1021/acsami.8b04081DOI Listing
May 2018

A new chaotic oscillator with free control.

Chaos 2017 Aug;27(8):083101

School of Electronic and Information Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China.

A novel chaotic system is explored in which all terms are quadratic except for a linear function. The slope of the linear function rescales the amplitude and frequency of the variables linearly while its zero intercept allows offset boosting for one of the variables. Therefore, a free-controlled chaotic oscillation can be obtained with any desired amplitude, frequency, and offset by an easy modification of the linear function. When implemented as an electronic circuit, the corresponding chaotic signal can be controlled by two independent potentiometers, which is convenient for constructing a chaos-based application system. To the best of our knowledge, this class of chaotic oscillators has never been reported.
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http://dx.doi.org/10.1063/1.4997051DOI Listing
August 2017

Systematic investigation on the turning point of over-inflammation to immunosuppression in CLP mice model and their characteristics.

Int Immunopharmacol 2017 Jan 19;42:49-58. Epub 2016 Nov 19.

Department of Pharmacology, College of Pharmacy, the Third Military Medical University, Chongqing 400038, PR China. Electronic address:

Immunosuppression is involved in refractory innate and adaptive immune responses and is considered to be the predominant driving force for mortality in sepsis. The cecal ligation and puncture (CLP) model is regarded as a golden standard model for sepsis study, but the turning point of over-inflammation to immunosuppression was reported differently. Herein, systematic investigation on the turning point of over-inflammation to immunosuppression in CLP mice model was carried out. The results showed only the mortality of mice challenged with of Pseudomonas aeruginosa on Day 1 not other days after the surgery was higher than that of other mice with Sham surgery, suggesting Day 1 after the CLP surgery might be the turning point. There was very low mortality even without death in Sham mice but the mortality was 80% after mice were challenged with 2.5×10, 5.0×10 and 1.0×10CFU/10g of Pseudomonas aeruginosa, further demonstrating Day 1 after the CLP surgery was the turning point. And, CLP mice presented low levels of pro-inflammatory and anti-inflammatory cytokines, and high bacterial loads on Day 1. Additionally, the amounts and proportion of blood cells and monocytes significantly changed, too. In conclusion, Day 1 after the CLP surgery was the turning point of over-inflammation to immunosuppression, and low levels of cytokines and high bacterial loads were the characteristics of this model on Day 1, which is significant for pharmacological investigation on sepsis.
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http://dx.doi.org/10.1016/j.intimp.2016.11.011DOI Listing
January 2017

Artesunate attenuated progression of atherosclerosis lesion formation alone or combined with rosuvastatin through inhibition of pro-inflammatory cytokines and pro-inflammatory chemokines.

Phytomedicine 2016 Oct 6;23(11):1259-66. Epub 2016 Jun 6.

Department of Pharmacology, College of Medicine, The Third Military Medical University, Chongqing 400038, P. R. China. Electronic address:

Backgrounds: Inflammation plays an important role in all stages of atherosclerosis, but little is known about the therapeutic effects of quenching inflammation in atherosclerotic lesions formation.

Purpose: Herein, the effect of artesunate, a derivant from artemisinin from the traditional Chinese herb sweet wormwood, could attenuate the progression of atherosclerosis lesion formation alone or combined with rosuvastatin in Western-type diet (WD) fed ApoE(-/-) mice, and explored its possible mechanisms.

Methods: The methods such as ELISA for plasma lipids and cytokines analyses, qRT-PCR and western blot for mRNA and protein expressions, and MTT assay for human umbilical vein endothelial cells (HUVECs) viability were used for in vivo and in vitro experiments.

Results: Artesunate could attenuate the progression of atherosclerosis lesion formation alone or combined with rosuvastatin in WD fed ApoE(-/-) mice without changes in food uptake, body weight and plasma lipids level, but with a significant reduction of pro-inflammatory cytokine, such as TNF-α and IL-6. Furthermore, artesunate could down-regulate the pro-inflammatory chemokines such as IL-8 and MCP-1 in aorta of mice. Besides, artesunate didn't influence IL-8 and MCP-1 secretion in HUVECs up-regulated by TNF-α, but inhibited IL-8 and MCP-1 secretion up-regulated by LPS.

Conclusion: AS attenuated progression of atherosclerosis lesion formation alone or combined with rosuvastatin through anti-inflammatory effect, resulting in down-regulation of TNF-α and IL-6, and further down-regulating IL-8 and MCP-1 expressions in aorta of WD fed ApoE(-/-) mice. Rosuvastatin combined with artesunate could more effectively attenuate the progression of atherosclerosis lesions than when treated by one of them, demonstrating that lipid-lowering agents combined with anti-inflammatory agents could provide the greater benefit for cardiovascular disease patients. Artesunate is worth further investigating as a candidate drug for the treatment of atherosclerosis.
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http://dx.doi.org/10.1016/j.phymed.2016.06.004DOI Listing
October 2016

Effect of additives on the properties of polyaniline nanofibers prepared by high gravity chemical oxidative polymerization.

Langmuir 2015 May 27;31(18):5155-63. Epub 2015 Apr 27.

†State Key Laboratory of Organic-Inorganic Composites and ‡Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029, P. R. China.

Polyaniline (PANI) nanofibers with improved properties were prepared by high gravity chemical oxidative polymerization in a rotating packed bed with the assistance of p-aminodiphenylamine (AD) and p-phenylenediamine (AP). The effects of reactor type, additive dosage, reaction temperature, and high-gravity level on the properties of products were investigated in detail. Three conclusions were made: (1) a small amount of additive can significantly improve some properties of the nanofibers such as uniformity, specific surface area, and specific capacitance; (2) in order to obtain high-quality nanofibers, the high-gravity level should coordinate with the reaction rate; (3) the molecular weight and conductivity of PANI decrease with the increase of additive dosage. The products have larger specific surface areas of up to 73.9 and 68.4 m(2)/g and consequently improved specific capacitance of up to 527.5 and 552 F/g for the PANI nanofibers prepared with AD and AP, respectively. However, the specific surface area and specific capacitance of pure PANI are only 49.1 m(2)/g and 333.3 F/g, respectively. This research provides a simple, reliable, and scalable method to produce PANI nanofibers of high performances.
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http://dx.doi.org/10.1021/la504996cDOI Listing
May 2015

Preparation and characterizations of BiVO₄/reduced graphene oxide nanocomposites with higher visible light reduction activities.

J Colloid Interface Sci 2015 May 16;445:330-336. Epub 2015 Jan 16.

State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China. Electronic address:

Bismuth vanadate/reduced graphene oxide (BiVO4/RGO) composites were synthesized by one-step hydrothermal method with graphite oxide, Bi(NO3)3 and NH4VO3 as precursors. The as-synthesized nanocomposites were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, UV-Vis spectroscopy (UV), fluorescence spectroscopy (FL) and electrochemical impedance spectroscopy (EIS). The reduced graphene oxide sheets were decorated by butterfly-like BiVO4 lamellas. Such combination not only alleviated the agglomeration of BiVO4 particles but also restrained the restacking of reduced graphene oxide. A preliminary study on the photo-reductions of Cr (VI) and CO2 under the illumination of simulated sunlight with as-synthesized BiVO4/RGO nanocomposites as catalyst was carried out. The nanocomposites showed better photo-catalytic activity than the conventional BiVO4 particles. The photo-reduction efficiency of BiVO4/RGO nanocomposites increased about 50.1% and the ethanol yield improved about 15.4 μmol/g-cat comparing with pure BiVO4. The enhancements of the photo-catalytic activities were attributed to the effective charge transfer of photo-generated electron from BiVO4 to RGO and improved absorption performance.
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http://dx.doi.org/10.1016/j.jcis.2015.01.017DOI Listing
May 2015

Electrochemical energy storage by polyaniline nanofibers: high gravity assisted oxidative polymerization vs. rapid mixing chemical oxidative polymerization.

Phys Chem Chem Phys 2015 Jan 28;17(2):1498-502. Epub 2014 Nov 28.

State Key Laboratory of Organic Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, P. R. China.

Polyaniline (PANI) nanofibers prepared by high gravity chemical oxidative polymerization in a rotating packed bed (RPB) have demonstrated a much higher specific capacitance of 667.6 F g(-1) than 375.9 F g(-1) of the nanofibers produced by a stirred tank reactor (STR) at a gravimetric current of 10 A g(-1). Meanwhile, the cycling stability of the electrode is 62.2 and 65.9% for the nanofibers from RPB and STR after 500 cycles, respectively.
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http://dx.doi.org/10.1039/c4cp03144jDOI Listing
January 2015

Substituent effect on the self-assembled structures of two carboxyl-functionalised phthalocyanine derivatives on highly oriented pyrolytic graphite.

J Nanosci Nanotechnol 2014 Jul;14(7):5375-9

The self-assembling behaviour of two kinds of 4-carboxyphenoxy phthalocyanines (Pc1 and Pc2) has been investigated by scanning tunneling microscope (STM). Pc1 and Pc2 are isomers with the same substituent at alpha- andbeta-position of the phthalocyanine core, respectively. Our STM results have shown that the Pc1 molecule fabricates into stable networks with nanoscale cavities, while Pc2 forms an unstable linear-like structure at the 1-heptanoic acid/graphite interface. The different supramolecular assembling structures may result from the different substituent position of the carboxyl groups which influence the formation of intermolecular hydrogen bonds.
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http://dx.doi.org/10.1166/jnn.2014.8272DOI Listing
July 2014

Green synthesis and photo-catalytic performances for ZnO-reduced graphene oxide nanocomposites.

J Colloid Interface Sci 2013 Dec 12;411:69-75. Epub 2013 Sep 12.

Key Lab of Organic and Inorganic Composite Materials, Beijing University of Chemical Technology, Beijing 100029, China.

The zinc oxide (ZnO)-reduced graphene oxide (RGO) nanocomposites were greenly synthesized by one-step hydrothermal reaction with ZnCl2 and graphite oxide (GO) as precursors without extra reductant. The photo-catalytic performances consisting of the photo-degradation of Rhodamine B (RhB) and the photo-reduction of CO2 under the illumination of simulated solar light at ambient temperature were investigated. It was validated that the ZnO spherical particles assembled by ZnO nanorods with an average diameter of 150nm are uniformly deposited on the RGO sheets. Meanwhile, due to the introduction of RGO, the light adsorption scope of ZnO is enlarged, the size of ZnO is decreased, the degree of crystallinity is improved and the self-aggregation of the ZnO particles is effectively prevented. Comparing with the pure ZnO particles, the efficiency of the nanocomposites for the photo-degradation of RhB is increased by 39% and the yield of methanol from the reduction of CO2 is improved by 75%. The mechanisms that may explain the enhanced properties of as-synthesized ZnO-RGO for both the photo-degradation of RhB and the reduction of CO2 were also proposed.
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http://dx.doi.org/10.1016/j.jcis.2013.08.050DOI Listing
December 2013
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