54 results on '"Guangwu Li"'
Search Results
2. Exploring the mechanism of olfactory recognition in the initial stage by modeling the emission spectrum of electron transfer.
- Author
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Shu Liu, Rao Fu, and Guangwu Li
- Subjects
Medicine ,Science - Abstract
Olfactory sense remains elusive regarding the primary reception mechanism. Some studies suggest that olfaction is a spectral sense, the olfactory event is triggered by electron transfer (ET) across the odorants at the active sites of odorant receptors (ORs). Herein we present a Donor-Bridge-Acceptor model, proposing that the ET process can be viewed as an electron hopping from the donor molecule to the odorant molecule (Bridge), then hopping off to the acceptor molecule, making the electronic state of the odorant molecule change along with vibrations (vibronic transition). The odorant specific parameter, Huang-Rhys factor can be derived from ab initio calculations, which make the simulation of ET spectra achievable. In this study, we revealed that the emission spectra (after Gaussian convolution) can be acted as odor characteristic spectra. Using the emission spectrum of ET, we were able to reasonably interpret the similar bitter-almond odors among hydrogen cyanide, benzaldehyde and nitrobenzene. In terms of isotope effects, we succeeded in explaining why subjects can easily distinguish cyclopentadecanone from its fully deuterated analogue cyclopentadecanone-d28 but not distinguishing acetophenone from acetophenone-d8.
- Published
- 2020
- Full Text
- View/download PDF
3. Data on the detail information of influence of substrate temperature on the film morphology and photovoltaic performance of non-fullerene organic solar cells
- Author
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Jicheng Zhang, SuFei Xie, Zhen Lu, Yang Wu, Hongmei Xiao, Xuejuan Zhang, Guangwu Li, Cuihong Li, Xuebo Chen, Wei Ma, and Zhishan Bo
- Subjects
Computer applications to medicine. Medical informatics ,R858-859.7 ,Science (General) ,Q1-390 - Abstract
This data contains additional data related to the article “Influence of Substrate Temperature on the Film Morphology and Photovoltaic Performance of Non-fullerene Organic Solar Cells” (Jicheng Zhang et al., In press) [1]. Data include measurement and characterization instruments and condition, detail condition to fabricate norfullerene solar cell devices, hole-only and electron-only devices. Detail condition about how to control the film morphology of devices via tuning the temperature of substrates was also displayed. More information and more convincing data about the change of film morphology for active layers fabricated from different temperature, which is attached to the research article of “Influence of Substrate Temperature on the Film Morphology and Photovoltaic Performance of Non-fullerene Organic Solar Cells” was given.
- Published
- 2017
- Full Text
- View/download PDF
4. Angularly fused diaza-dinaphthopyrenes: regio-selective synthesis, crystal structures and isomer-dependent mechanochromic fluorescent properties
- Author
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Yan Kou, Guangwu Li, Yi Han, Mengwei Li, Tingting Wang, Zhiyu Qu, and Yulan Chen
- Subjects
General Chemistry - Abstract
A one-pot synthesis of the first angularly fused diaza-dinaphthopyrene isomers with central and axial symmetry is reported. They showed isomer-specific crystal structures, tunable optical and redox properties, and turn-on mechanochromic fluorescence.
- Published
- 2023
5. A graphyne spoked wheel
- Author
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Boyi Zhang, Shaofei Wu, Xudong Hou, Guangwu Li, Yong Ni, Qiuyu Zhang, Jun Zhu, Yi Han, Peng Wang, Zhe Sun, and Jishan Wu
- Subjects
General Chemical Engineering ,Biochemistry (medical) ,Materials Chemistry ,Environmental Chemistry ,General Chemistry ,Biochemistry - Published
- 2022
6. Identification of T2W hypointense ring as a novel noninvasive indicator for glioma grade and IDH genotype
- Author
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Yawen Lu, Ningfang Du, Xuhao Fang, Weiquan Shu, Wei Liu, Xinxin Xu, Yao Ye, Li Xiao, Renling Mao, Kefeng Li, Guangwu Lin, and Shihong Li
- Subjects
Glioma ,Magnetic resonance imaging ,Isocitrate dehydrogenase ,T2W hypointense ring ,T2-FLAIR mismatch ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background This study aimed to evaluate the T2W hypointense ring and T2-FLAIR mismatch signs in gliomas and use these signs to construct prediction models for glioma grading and isocitrate dehydrogenase (IDH) mutation status. Methods Two independent radiologists retrospectively evaluated 207 glioma patients to assess the presence of T2W hypointense ring and T2-FLAIR mismatch signs. The inter-rater reliability was calculated using the Cohen’s kappa statistic. Two logistic regression models were constructed to differentiate glioma grade and predict IDH genotype noninvasively, respectively. Receiver operating characteristic (ROC) analysis was used to evaluate the developed models. Results Of the 207 patients enrolled (119 males and 88 females, mean age 51.6 ± 14.8 years), 45 cases were low-grade gliomas (LGGs), 162 were high-grade gliomas (HGGs), 55 patients had IDH mutations, and 116 were IDH wild-type. The number of T2W hypointense ring signs was higher in HGGs compared to LGGs (p
- Published
- 2024
- Full Text
- View/download PDF
7. Facile Synthesis of Aryl-Substituted Cycloarenes via Bismuth(III) Triflate-Catalyzed Cyclization of Vinyl Ethers
- Author
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Yi Han, Guangwu Li, Wei Fan, Shaoqiang Dong, Jishan Wu, and Xuefeng Lu
- Subjects
chemistry.chemical_classification ,Aryl ,chemistry.chemical_element ,Polycyclic aromatic hydrocarbon ,Aromaticity ,General Chemistry ,Electronic structure ,Combinatorial chemistry ,Bismuth ,Catalysis ,chemistry.chemical_compound ,chemistry ,Kekulene ,Trifluoromethanesulfonate - Abstract
Cycloarenes are an essential class of polycyclic aromatic hydrocarbons with unique electronic structure, but their synthesis is very challenging. Herein, we report a facile synthetic strategy prima...
- Published
- 2021
8. Perylene‐Fused, Aggregation‐Free Polycyclic Aromatic Hydrocarbons for Solution‐Processed Distributed Feedback Lasers
- Author
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María A. Díaz-García, Juan Casado, Guangwu Li, Ya Zou, José M. Villalvilla, José A. Quintana, Pedro G. Boj, Shaofei Wu, Víctor Bonal, Sergio Moles Quintero, Qing Jiang, Yong Ni, Jishan Wu, Universidad de Alicante. Departamento de Física Aplicada, Universidad de Alicante. Departamento de Óptica, Farmacología y Anatomía, Universidad de Alicante. Instituto Universitario de Materiales, and Física de la Materia Condensada
- Subjects
Física de la Materia Condensada ,010405 organic chemistry ,Library science ,General Medicine ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Polycyclic aromatic hydrocarbons ,Catalysis ,0104 chemical sciences ,Solution processed ,chemistry.chemical_compound ,Scholarship ,chemistry ,Física Aplicada ,Tier 2 network ,Political science ,Organic lasers ,Amplified spontaneous emission ,Perylene ,Dyes ,Óptica - Abstract
Perylene‐fused, aggregation‐free polycyclic aromatic hydrocarbons with partial zigzag periphery (ZY‐01, ZY‐02, and ZY‐03) were synthesized. X‐ray crystallographic analysis reveals that there is no intermolecular π–π stacking in any of the three molecules, and as a result, they show moderate‐to‐high photoluminescence quantum yield in both solution and in the solid state. They also display the characteristic absorption and emission spectra of perylene dyes. ZY‐01 and ZY‐02 with a nearly planar π‐conjugated skeleton exhibit amplified spontaneous emission (ASE) when dispersed in polystyrene thin films. Solution‐processed distributed feedback lasers have been fabricated using ZY‐01 and ZY‐02 as active gain materials, both showing narrow emission linewidth (
- Published
- 2020
9. Potassium Titanate Supported Atomically Dispersed Palladium for Catalytic Oxidation
- Author
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Li Zhou, Shuren He, Xiaohong Xu, Guangwu Li, and Chuancheng Jia
- Subjects
General Chemical Engineering ,General Engineering ,General Physics and Astronomy ,Medicine (miscellaneous) ,General Materials Science ,Biochemistry, Genetics and Molecular Biology (miscellaneous) - Abstract
Single-atom catalysts based on noble metals provide efficient atomic utilization along with enhanced reactivity. Herein, a convenient strategy to construct atomically dispersed palladium catalyst on layered potassium titanate (KTO), which has enhanced interaction between the TiO
- Published
- 2022
10. Tailoring Long-Range Superlattice Chirality in the Molecular Selfassemblies via Weak Fluorine-Mediated Interactions
- Author
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Mykola Telychko, Lulu Wang, Chia-Hsiu Hsu, Guangwu Li, Xinnan Peng, Shaotang Song, Jie Su, Feng-Chuan Chuang, Jishan Wu, Richard Ming Wah Wong, and Jiong Lu
- Abstract
Controllable fabrication of the enantiospecific molecular superlattices is a matter of imminent scientific and technological interest. Herein, we demonstrate that long-range superlattice chirality in molecular self-assemblies can be tailored by tuning the interplay of weak intermolecular non-covalent interactions. Different chiral recognition patterns are achieved in the two molecular self-assemblies comprised by two molecular enantiomers with identical steric conformations, derived from the hexaphenylbenzene – the smallest star-shaped polyphenylene. By means of high-resolution scanning tunneling microscopy measurements, we demonstrate that functionalization of star-shaped polyphenylene with fluorine (F) atoms leads to the formation of molecular self-assemblies with the distinct long-range chiral recognition patterns. We employed the density functional theory calculations to quantify F-mediated lone pair F ···π, C-H··· F, F···F interactions attributed to the tunable enantiospecific molecular self-organizations. Our findings underpin a viable route to tailor long-range chiral recognition patterns in supramolecular assemblies by engineering the weak non-covalent intermolecular interactions.
- Published
- 2021
11. Ultrahigh-yield on-surface synthesis and assembly of circumcoronene into a chiral electronic Kagome-honeycomb lattice
- Author
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Xinnan Peng, Shaotang Song, Mykola Telychko, Guangwu Li, Pavel Jelínek, Diego Soler-Polo, Jie Su, Pingo Mutombo, Jishan Wu, Jiong Lu, Ming Joo Koh, Mark T. Edmonds, and UAM. Departamento de Física Teórica de la Materia Condensada
- Subjects
Materials science ,Nanographenes ,Tight-Binding Calculations ,Superlattice ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,High Yield ,Scanning probe microscopy ,Honeycomb ,Molecule ,Topology (chemistry) ,Research Articles ,Cascade Reactions ,Multidisciplinary ,Metallic Surface ,Self Organizations ,SciAdv r-articles ,Física ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Methyl Radical ,Zigzag ,Chemical physics ,Intramolecular force ,Density functional theory ,0210 nano-technology ,Research Article ,Surface Chemistry ,Honeycomb Lattices - Abstract
Bottom-up surface-assisted synthesis of circumcoronene self-assembly enables realization of artificial electronic lattice., On-surface synthesis has revealed remarkable potential in the fabrication of atomically precise nanographenes. However, surface-assisted synthesis often involves multiple-step cascade reactions with competing pathways, leading to a limited yield of target nanographene products. Here, we devise a strategy for the ultrahigh-yield synthesis of circumcoronene molecules on Cu(111) via surface-assisted intramolecular dehydrogenation of the rationally designed precursor, followed by methyl radical-radical coupling and aromatization. An elegant electrostatic interaction between circumcoronenes and metallic surface drives their self-organization into an extended superlattice, as revealed by bond-resolved scanning probe microscopy measurements. Density functional theory and tight-binding calculations reveal that unique hexagonal zigzag topology of circumcoronenes, along with their periodic electrostatic landscape, confines two-dimensional electron gas in Cu(111) into a chiral electronic Kagome-honeycomb lattice with two emergent electronic flat bands. Our findings open up a new route for the high-yield fabrication of elusive nanographenes with zigzag topologies and their superlattices with possible nontrivial electronic properties.
- Published
- 2021
12. Ultra-high Yield On-surface Synthesis and Assembly of Circumcoronene into Chiral Electronic Kagome-honeycomb Lattice
- Author
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Jishan Wu, Diego Soler-Polo, Guangwu Li, Shaotang Song, Pingo Mutombo, Xinnan Peng, Pavel Jelínek, Ming Joo Koh, Jiong Lu, Mykola Telychko, Jie Su, and Mark T. Edmonds
- Subjects
Scanning probe microscopy ,Materials science ,Zigzag ,Chemical physics ,Superlattice ,Honeycomb ,Molecule ,Density functional theory ,Non-contact atomic force microscopy ,Topology (chemistry) - Abstract
On-surface synthesis has revealed remarkable potential in the fabrication of a plethora of elusive nanographenes with tailored structural, electronic and magnetic properties unattainable by conventional wet-chemistry synthesis. Unfortunately, surface-assisted synthesis often involves multiple-step cascade reactions with competing pathways, leading to the formation of a diversity of products with limited yield, which reduces its feasibility towards the large-scale production for future technological applications. Here, we devise a new on-surface synthetic strategy for the ultra-high yield synthesis of a hexagonal nanographene with six zigzag edges, namely circumcoronene on Cu(111) via surfaceassisted intramolecular dehydrogenation of the rationally-designed precursor molecule, followed by methyl radical-radical coupling and aromatization. An elegant electrostatic interaction between circumcoronene and Cu(111) drives their self-organization into an extended superlattice, as revealed by bond-resolved low-temperature scanning probe microscopy and spectroscopy measurements. Density functional theory and tight-binding calculations reveal that unique hexagonal zigzag topology of circumcoronenes, along with their periodic electrostatic landscape confines two-dimensional (2D) electron gas in Cu(111) surface into chiral electronic Kagome-honeycomb lattice with two emergent electronic flat bands. Our findings open up a new route for the high-yield fabrication of elusive nanographenes with zigzag topologies and their novel 2D superlattices with possible nontrivial electronic properties towards their future technological applications.
- Published
- 2020
13. Exploring the mechanism of olfactory recognition in the initial stage by modeling the emission spectrum of electron transfer
- Author
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Rao Fu, Guangwu Li, and Shu Liu
- Subjects
Social Sciences ,02 engineering and technology ,Electron Transfer ,Receptors, Odorant ,01 natural sciences ,Spectral line ,Emission Spectra ,Isotopes ,Hydrogen Cyanide ,Kinetic isotope effect ,Psychology ,Vibronic spectroscopy ,Emission spectrum ,Materials ,Multidisciplinary ,Organic Compounds ,Chemistry ,Physics ,Classical Mechanics ,food and beverages ,021001 nanoscience & nanotechnology ,Smell ,Chemical physics ,Benzaldehydes ,Physical Sciences ,Engineering and Technology ,Medicine ,Sensory Perception ,0210 nano-technology ,psychological phenomena and processes ,Research Article ,Science ,Cell Respiration ,Materials Science ,Material Properties ,Vibration Engineering ,Olfaction ,010402 general chemistry ,Vibration ,Olfactory Receptor Neurons ,Electron Transport ,Electron transfer ,Ab initio quantum chemistry methods ,Humans ,Molecule ,Nitrobenzenes ,Chemical Physics ,Mechanical Engineering ,Organic Chemistry ,Chemical Compounds ,Biology and Life Sciences ,Olfactory Perception ,0104 chemical sciences ,Odorants ,Neuroscience - Abstract
Olfactory sense remains elusive regarding the primary reception mechanism. Some studies suggest that olfaction is a spectral sense, the olfactory event is triggered by electron transfer (ET) across the odorants at the active sites of odorant receptors (ORs). Herein we present a Donor-Bridge-Acceptor model, proposing that the ET process can be viewed as an electron hopping from the donor molecule to the odorant molecule (Bridge), then hopping off to the acceptor molecule, making the electronic state of the odorant molecule change along with vibrations (vibronic transition). The odorant specific parameter, Huang–Rhys factor can be derived from ab initio calculations, which make the simulation of ET spectra achievable. In this study, we revealed that the emission spectra (after Gaussian convolution) can be acted as odor characteristic spectra. Using the emission spectrum of ET, we were able to reasonably interpret the similar bitter-almond odors among hydrogen cyanide, benzaldehyde and nitrobenzene. In terms of isotope effects, we succeeded in explaining why subjects can easily distinguish cyclopentadecanone from its fully deuterated analogue cyclopentadecanone-d28 but not distinguishing acetophenone from acetophenone-d8.
- Published
- 2020
14. Knowledge, attitude and intentions towards nursing profession among Chinese high school graduates in central China
- Author
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Kenneth J. Gruber, Guangwu Li, Yuye Ke, Li Li, Jie Hu, and Shuzhen Zhu
- Subjects
Demographics ,Nursing ,education ,Multilevel model ,Central china ,Economic shortage ,Social media ,Future career ,Family income ,China ,Psychology - Abstract
Background and objective: Current nursing shortages and low willingness of young people to choose nursing as a career are of major concern in many countries. This study examined the knowledge, attitude and intention towards the nursing profession among high school graduates in China and factors associated with graduate’ intention to enroll in nursing program. Methods: A cross-sectional study was conducted using a random sampling. A total of 3,764 high school graduates of selected schools in Central China participated in the study. Data were collected with online survey including demographics, knowledge of and attitude towards nursing and intention to choose nursing. Pearson’s correlations and Hierarchical regression analyses were performed. Results: Less than 10% of the participants expressed interest in a future career in nursing. Knowledge and attitude about nursing were positively associated with intention to study nursing. Both participants’ education, family income and attitude significantly predicted intention to study nursing in the hierarchy regression model ( p < .001). Conclusions: Recruitment and retention strategies need to focus on addressing improving knowledge about the roles of nurse among high school students. Nursing administrators and educators should provide information about nursing profession on Websites and social media or programs for high school students with early clinical exposure to nursing to increase their knowledge and change their attitudes toward nursing.
- Published
- 2021
15. Data on the detail information of influence of substrate temperature on the film morphology and photovoltaic performance of non-fullerene organic solar cells
- Author
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Xuejuan Zhang, Guangwu Li, Yang Wu, Zhen Lu, Jicheng Zhang, Xuebo Chen, Hongmei Xiao, Cuihong Li, Sufei Xie, Zhishan Bo, and Wei Ma
- Subjects
Materials science ,Fullerene ,Morphology (linguistics) ,Organic solar cell ,Materials Science ,Nanotechnology ,02 engineering and technology ,Substrate (electronics) ,lcsh:Computer applications to medicine. Medical informatics ,010402 general chemistry ,01 natural sciences ,Polymer solar cell ,law.invention ,law ,Solar cell ,lcsh:Science (General) ,Multidisciplinary ,business.industry ,Photovoltaic system ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Characterization (materials science) ,lcsh:R858-859.7 ,Optoelectronics ,0210 nano-technology ,business ,lcsh:Q1-390 - Abstract
This data contains additional data related to the article “Influence of Substrate Temperature on the Film Morphology and Photovoltaic Performance of Non-fullerene Organic Solar Cells” (Jicheng Zhang et al., In press) [1]. Data include measurement and characterization instruments and condition, detail condition to fabricate norfullerene solar cell devices, hole-only and electron-only devices. Detail condition about how to control the film morphology of devices via tuning the temperature of substrates was also displayed. More information and more convincing data about the change of film morphology for active layers fabricated from different temperature, which is attached to the research article of “Influence of Substrate Temperature on the Film Morphology and Photovoltaic Performance of Non-fullerene Organic Solar Cells” was given.
- Published
- 2017
16. Improve the diagnosis of idiopathic normal pressure hydrocephalus by combining abnormal cortical thickness and ventricular morphometry
- Author
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Yifeng Yang, Meijing Yan, Xiao Liu, Shihong Li, and Guangwu Lin
- Subjects
idiopathic normal pressure hydrocephalus (iNPH) ,brain morphometry ,machine learning ,multi-feature fusion ,diagnosis ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
BackgroundThe primary imaging markers for idiopathic Normal Pressure Hydrocephalus (iNPH) emphasize morphological measurements within the ventricular system, with no attention given to alterations in brain parenchyma. This study aimed to investigate the potential effectiveness of combining ventricular morphometry and cortical structural measurements as diagnostic biomarkers for iNPH.MethodsA total of 57 iNPH patients and 55 age-matched healthy controls (HC) were recruited in this study. Firstly, manual measurements of ventricular morphology, including Evans Index (EI), z-Evans Index (z-EI), Cella Media Width (CMW), Callosal Angle (CA), and Callosal Height (CH), were conducted based on MRI scans. Cortical thickness measurements were obtained, and statistical analyses were performed using surface-based morphometric analysis. Secondly, three distinct models were developed using machine learning algorithms, each based on a different input feature: a ventricular morphology model (LVM), a cortical thickness model (CT), and a fusion model (All) incorporating both features. Model performances were assessed using 10-fold cross validation and tested on an independent dataset. Model interpretation utilized Shapley Additive Interpretation (SHAP), providing a visualization of the contribution of each variable in the predictive model. Finally, Spearman correlation coefficients were calculated to evaluate the relationship between imaging biomarkers and clinical symptoms.ResultsiNPH patients exhibited notable differences in cortical thickness compared to HC. This included reduced thickness in the frontal, temporal, and cingulate cortices, along with increased thickness in the supracentral gyrus. The diagnostic performance of the fusion model (All) for iNPH surpassed that of the single-feature models, achieving an average accuracy of 90.43%, sensitivity of 90.00%, specificity of 90.91%, and Matthews correlation coefficient (MCC) of 81.03%. This improvement in accuracy (6.09%), sensitivity (11.67%), and MCC (11.25%) compared to the LVM strategy was significant. Shap analysis revealed the crucial role of cortical thickness in the right isthmus cingulate cortex, emerging as the most influential factor in distinguishing iNPH from HC. Additionally, significant correlations were observed between the typical triad symptoms of iNPH patients and cortical structural alterations.ConclusionThis study emphasizes the significant role of cortical structure changes in the diagnosis of iNPH, providing a novel insights for assisting clinicians in improving the identification and detection of iNPH.
- Published
- 2024
- Full Text
- View/download PDF
17. Variability scaling and capacity planning in Covid-19 pandemic
- Author
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L. Jeff Hong, Guangwu Liu, Jun Luo, and Jingui Xie
- Subjects
Covid-19 ,Capacity planning ,Variability scaling ,Demand aggregation ,Network model ,Risk pooling effect ,Science (General) ,Q1-390 - Abstract
Capacity planning is a very important global challenge in the face of Covid-19 pandemic. In order to hedge against the fluctuations in the random demand and to take advantage of risk pooling effect, one needs to have a good understanding of the variabilities in the demand of resources. However, Covid-19 predictive models that are widely used in capacity planning typically often predict the mean values of the demands (often through the predictions of the mean values of the confirmed cases and deaths) in both the temporal and spatial dimensions. They seldom provide trustworthy prediction or estimation of demand variabilities, and therefore, are insufficient for proper capacity planning. Motivated by the literature on variability scaling in the areas of physics and biology, we discovered that in the Covid-19 pandemic, both the confirmed cases and deaths exhibit a common variability scaling law between the average of the demand μ and its standard deviation σ, that is, σ∝μβ, where the scaling parameter β is typically in the range of 0.65 to 1, and the scaling law exists in both the temporal and spatial dimensions. Based on the mechanism of contagious diseases, we further build a stylized network model to explain the variability scaling phenomena. We finally provide simple models that may be used for capacity planning in both temporal and spatial dimensions, with only the predicted mean demand values from typical Covid-19 predictive models and the standard deviations of the demands derived from the variability scaling law.
- Published
- 2023
- Full Text
- View/download PDF
18. Insights into the influence of fluorination positions on polymer donor materials on photovoltaic performance
- Author
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Zhishan Bo, Danyang Ma, Guangwu Li, Xue Gong, Wei Ma, Jianya Chen, Ran Hou, Cuihong Li, and Shiyu Feng
- Subjects
Condensation polymer ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Polymer solar cell ,Biomaterials ,chemistry.chemical_compound ,Quinoxaline ,Materials Chemistry ,Copolymer ,Organic chemistry ,Electrical and Electronic Engineering ,chemistry.chemical_classification ,Energy conversion efficiency ,General Chemistry ,Polymer ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Acceptor ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,chemistry ,Fluorine ,0210 nano-technology - Abstract
To explore the influence of fluoro substitution position and number on optical, electrochemical and photovoltaic properties, three novel donor-acceptor (D-A) alternative copolymers (PHF, PFH and PFF) were synthesized by Stille polycondensation of 2,3-diphenyl-5,8-di(thiophen-2-yl)quinoxaline (DTQx) acceptor unit and indacenodithiophene (IDT) donor unit. As films, PHF and PFF comprising two fluoro substituents on the lateral phenyl groups displayed a broad absorption ranging from 350 to 700 nm; whereas PFH containing two fluorine atoms on the polymer main chain exhibited a slightly narrower absorption ranging from 350 to 650 nm. In addition, fluoro substitution on the polymer main chain can lower the HOMO level of the resulted polymers. As expected, PFH and PFF possess deeper HOMO energy level than PHF. Polymer solar cells (PSCs) were fabricated with these three polymers as donor materials and PC71BM as acceptor material. PHF based PSCs gave a power conversion efficiency (PCE) of 7.2% with a Voc of 0.84 V, a Jsc of 12.46 mA/cm2 and an FF of 0.69. And PFH based PSCs showed a PCE of 6.19% with a Voc of 0.93 V, a Jsc of 9.57 mA/cm2 and an FF 0.70. However, a PCE of only 2.9% with a Voc of 0.92 V, a Jsc of 4.61 mA/cm2 and an FF of 0.68 was obtained for PFF based PSCs. Transmission electron microscopy (TEM) and resonant soft X-ray scattering (R-SoXS) studies indicated that the introduction of four fluorine atoms at each repeating unit can spoil the morphology of active layer. These results highlight the importance of fluorination position and number to the performance of PSCs.
- Published
- 2017
19. Implementing Ecological Paradigm Teaching Strategy on Sports Class Quality of China: An Action Research Study of a College Sports Class.
- Author
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Guangwu Li and LeeHsing Lu
- Subjects
COLLEGE sports ,SPORTS psychology ,ACTION research ,ATHLETIC ability ,STUDENT health - Abstract
Purpose- As the health of Chinese college students continues to decline, people realize that the quality of college sport class quality is one of the main factors affecting student health. This research is through ODI to change the teaching strategy, and improve the sports motivation, sports ability and Satisfaction with teachers. It will verify the effectiveness and feasibility of ODI methods in China's sport class. Design/Methodology/Approach- Use a dual experimental group design, combination of qualitative and quantitative action research. Collect qualitative and quantitative data before and after ODI, Pairedsample t-test, Pearson correlation, and regression analysis were used to determine. This organization is a public university in the south of China. sports teachers (n=3), college students (n=127). Findings- The implementation of ODI can significantly improve sports class quality; There is a significant causal relationship between the independent variables of ecological paradigm teaching strategy (Leadership, Managerial, Social, Vector, Instructional) and the dependent variables of Sports class quality; the dependent variables (Sports motivation, Sports ability, Satisfaction with teachers) are highly correlated, Intervention of one factor can predict another factor. Practical Implications- The research will have a positive impact on the health of Shaoguan University students; The results will be used as reference for the improvement of physical education teaching in Chinese universities. Originality/Value- The study verifies the feasibility of organizational development intervention methods in Chinese sport classes; Put forward the "Ecological Paradigm Teaching Strategy Model"; Summarizes the theoretical framework, conceptual framework and action basis; it is an innovative research based on the combination of organizational development and sports class. [ABSTRACT FROM AUTHOR]
- Published
- 2021
20. MiR-940 Inhibited Cell Growth and Migration in Triple-Negative Breast Cancer
- Author
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Xiaobo Zhao, Jiani Hu, Lina Zhang, Jingdong Li, Hongwei Yang, Shishan Deng, Jun Jiang, Tianyong Xing, Maoshan Chen, Lingmi Hou, and Guangwu Li
- Subjects
0301 basic medicine ,CA15-3 ,Pathology ,medicine.medical_specialty ,Kruppel-Like Transcription Factors ,Triple Negative Breast Neoplasms ,Biology ,03 medical and health sciences ,0302 clinical medicine ,Breast cancer ,Western blot ,Cell Movement ,Cell Line, Tumor ,microRNA ,medicine ,Humans ,Molecular Biology ,Cells, Cultured ,Triple-negative breast cancer ,Cell Proliferation ,medicine.diagnostic_test ,Cell growth ,Cancer ,General Medicine ,Prognosis ,medicine.disease ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cancer research ,Female ,Cell Migration Assays - Abstract
BACKGROUND Breast cancer is the main type of cancer in women, and triple-negative breast cancer (TNBC) is a unique subtype of breast cancer. The expression of miR-940 has been shown to play an important role in various cancers; however, the role of miR-940 in TNBC remains unknown. MATERIAL AND METHODS The expression of miR-940 in TNBC tissues or cells were tested by qRT-PCR; the expression of miR-940 in cells were overexpressed by miR-940 mimics, and suppressed by anti-miR-940. Bioinformatics algorithms from TargetScanHuman were used to predict the target genes of miR-940. The interaction between miR-940 and ZNF24 was confirmed by dual luciferase assays. The protein level was assayed by Western blot. RESULTS TNBC tissues and cells showed lower miR-940 levels. CONCLUSIONS MiR-940 inhibited cellular proliferation and migration in TNBC.
- Published
- 2016
21. Exploring the Mechanism of Olfactory Recognition at the Initial Stage by Modeling the Emission Spectrum of Electron Transfer
- Author
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Shu Liu, Rao Fu, and Guangwu Li
- Subjects
Electron transfer ,Chemical physics ,Chemistry ,Ab initio quantum chemistry methods ,Kinetic isotope effect ,Vibronic spectroscopy ,Molecule ,food and beverages ,Emission spectrum ,Olfaction ,Spectral line ,psychological phenomena and processes - Abstract
Olfactory sense remains elusive regarding the primary reception mechanism. Some studies suggest that olfaction is a spectral sense, the olfactory event is triggered by electron transfer (ET) across the odorants at the active sites of odorant receptors (ORs). Herein we present a Donor-Bridge-Acceptor model, proposing that the ET process can be viewed as an electron hopping from the donor molecule to the odorant molecule (Bridge), then hopping off to the acceptor molecule, making the electronic state of the odorant molecule change along with vibrations (vibronic transition). The odorant specific parameter, Huang–Rhys factor can be derived from ab initio calculations, which make the simulation of ET spectra achievable. In this study, we revealed that the emission spectra (after Gaussian convolution) can be acted as odor characteristic spectra. Using the emission spectrum of ET, we were able to reasonably interpret the similar bitter-almond odors among hydrogen cyanide, benzaldehyde and nitrobenzene. In terms of isotope effects, we succeeded in explaining why subjects can easily distinguish cyclopentadecanone from its fully deuterated analogue cyclopentadecanone-d28 but not distinguishing acetophenone from acetophenone-d8.
- Published
- 2019
- Full Text
- View/download PDF
22. Activation of serotonin 5-HT2C receptor suppresses behavioral sensitization and naloxone-precipitated withdrawal symptoms in heroin-treated mice
- Author
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Yong-Mei Zhang, Robert W. Stackman, Liuyi Dong, Xian Wu, Gang Pang, Guangwu Li, Shengchun Xu, and Gongliang Zhang
- Subjects
Male ,Agonist ,medicine.medical_specialty ,medicine.drug_class ,Motor Activity ,Pharmacology ,Clonidine ,Article ,Heroin ,Lorcaserin ,Mice ,Naloxone ,Internal medicine ,mental disorders ,Adrenergic alpha-2 Receptor Agonists ,Receptor, Serotonin, 5-HT2C ,medicine ,Animals ,Behavior, Animal ,Kindling ,General Neuroscience ,Benzazepines ,Substance Withdrawal Syndrome ,5-HT2C receptor ,Endocrinology ,Morphine ,Central Nervous System Stimulants ,Psychology ,Serotonin 5-HT2 Receptor Agonists ,medicine.drug - Abstract
Abuse and dependence to heroin has evolved into a global epidemic as a significant clinical and societal problem with devastating consequences. Repeated exposure to heroin can induce long-lasting behavioral sensitization and withdrawal. Pharmacological activation of 5-HT2C receptors (5-HT2CRs) suppresses psychostimulant-induced drug-seeking and behavioral sensitization. The present study examined the effect of a selective 5-HT2CR agonist lorcaserin on behavioral sensitization and naloxone-precipitated withdrawal symptoms in heroin-treated mice. Male mice received heroin (1.0 mg/kg, s.c.) twice a day for 3 days and then drug treatment was suspended for 5 days. On day 9, a challenge dose of heroin (1.0 mg/kg) was administered to examine the expression of behavioral sensitization. Lorcaserin administered during the development, withdrawal or expression stage suppressed heroin-induced behavioral sensitization on day 9. Another cohort of mice received increasing doses of heroin over a 4.5-day period. Lorcaserin, or the positive control clonidine (an α2-adrenoceptor agonist) suppressed naloxone-precipitated withdrawal symptoms in heroin-treated mice. These findings suggest that activation of 5-HT2CRs suppresses behavioral sensitization and withdrawal in heroin-treated mice. Thus, pharmacological activation of 5-HT2CRs may represent a new avenue for the treatment of heroin addiction.
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- 2015
23. The Antidepressant-Like Effect of Vanillin Aroma Involves Serum Magnesium and Brain BDNF
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Yingxian Luo, Zhenhua Ren, Guangwu Li, Xu Jinyong, and Xiaoming Zhang
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Brain-derived neurotrophic factor ,Relaxation (psychology) ,business.industry ,Vanillin ,Olfaction ,Pharmacology ,medicine.disease ,Psychiatry and Mental health ,chemistry.chemical_compound ,Nerve growth factor ,chemistry ,Medicine ,Major depressive disorder ,Neurology (clinical) ,business ,Depression (differential diagnoses) ,Aromatherapy - Abstract
Depression is a major global public health concern. The variable effectiveness and undesirable side effects of antidepressant medication have prompted the search for alternative treatments. Olfaction plays an important role in emotion regulation in our daily life. Pleasant odorants would evoke positive emotions, inducing relaxation and calmness. The beneficial effects of vanillin aromatherapy on depression model rats were investigated in our previous research. Here, biochemical molecules including serum magnesium and brain derived nerve growth factor (BDNF) were further detected to investigate the possible underlying mechanisms. Results showed that the administration of vanillin aromatherapy restored the serum magnesium and brain BDNF which might mediate remission of depression. This suggests that vanillin aromatherapy could be considered as a potential alternative therapy for alleviating psychological responses among people suffering from major depressive disorder.
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- 2018
24. An initial study on the predictive value using multiple MRI characteristics for Ki-67 labeling index in glioma
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Ningfang Du, Weiquan Shu, Kefeng Li, Yao Deng, Xinxin Xu, Yao Ye, Feng Tang, Renling Mao, Guangwu Lin, Shihong Li, and Xuhao Fang
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Glioma ,Magnetic resonance imaging ,Ki-67 labeling index ,Diffusion-weighted magnetic resonance imaging ,Apparent diffusion coefficient ,Peritumoral edema ,Medicine - Abstract
Abstract Background and purpose Ki-67 labeling index (LI) is an important indicator of tumor cell proliferation in glioma, which can only be obtained by postoperative biopsy at present. This study aimed to explore the correlation between Ki-67 LI and apparent diffusion coefficient (ADC) parameters and to predict the level of Ki-67 LI noninvasively before surgery by multiple MRI characteristics. Methods Preoperative MRI data of 166 patients with pathologically confirmed glioma in our hospital from 2016 to 2020 were retrospectively analyzed. The cut-off point of Ki-67 LI for glioma grading was defined. The differences in MRI characteristics were compared between the low and high Ki-67 LI groups. The receiver operating characteristic (ROC) curve was used to estimate the accuracy of each ADC parameter in predicting the Ki-67 level, and finally a multivariate logistic regression model was constructed based on the results of ROC analysis. Results ADCmin, ADCmean, rADCmin, rADCmean and Ki-67 LI showed a negative correlation (r = − 0.478, r = − 0.369, r = − 0.488, r = − 0.388, all P
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- 2023
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25. Ultrahigh-yield on-surface synthesis and assembly of circumcoronene into a chiral electronic Kagome-honeycomb lattice.
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Mykola Telychko, Guangwu Li, Pingo Mutombo, Diego Soler-Polo, Xinnan Peng, Jie Su, Shaotang Song, Ming Joo Koh, Mark Edmonds, Pavel Jelínek, Jishan Wu, and Jiong Lu
- Subjects
- *
ELECTRON gas , *CONDENSED matter physics , *THERMOCHEMISTRY , *FRONTIER orbitals - Abstract
The article discusses about the ultrahigh-yield on-surface synthesis and assembly of circumcoronene into a chiral electronic Kagome-honeycomb lattice. It mentions that on-surface synthesis has revealed remarkable potential in the fabrication of atomically precise nanographenes. It discusses that high-yield fabrication of elusive nanographenes with zigzag topologies.
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- 2021
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26. Blockade of Serotonin 5-HT2A Receptors Suppresses Behavioral Sensitization and Naloxone-Precipitated Withdrawal Symptoms in Morphine-Treated Mice
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Gongliang Zhang, Yong-Mei Zhang, Gang Pang, Guangwu Li, Ruoying Mao, Xian Wu, Xueke Liu, Robert W. Stackman, Liuyi Dong, and Xinrong Tao
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0301 basic medicine ,hippocampus ,Hippocampus ,Neurotransmission ,Pharmacology ,5-HT2A receptor ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Pharmacology (medical) ,Receptor ,Original Research ,prefrontal cortex ,business.industry ,withdrawal ,Antagonist ,behavioral sensitization ,morphine ,Blockade ,serotonin ,030104 developmental biology ,Opioid ,Morphine ,Serotonin ,business ,030217 neurology & neurosurgery ,medicine.drug - Abstract
The increasing prescription of opioids is fueling an epidemic of addiction and overdose deaths. Morphine is a highly addictive drug characterized by a high relapse rate – even after a long period of abstinence. Serotonin (5-HT) neurotransmission participates in the development of morphine dependence, as well as the expression of morphine withdrawal. In this study, we examined the effect of blockade of 5-HT2A receptors (5-HT2ARs) on morphine-induced behavioral sensitization and withdrawal in male mice. 5-HT2AR antagonist MDL 11,939 (0.5 mg/kg, i.p.) suppressed acute morphine (5.0 mg/kg, s.c.)-induced increase in locomotor activity. Mice received morphine (10 mg/kg, s.c.) twice a day for 3 days and then drug treatment was suspended for 5 days. On day 9, a challenge dose of morphine (10 mg/kg) was administered to induce the expression of behavioral sensitization. MDL 11,939 (0.5 mg/kg, i.p.) pretreatment suppressed the expression of morphine-induced behavioral sensitization. Another cohort of mice received increasing doses of morphine over a 7-day period to induce morphine-dependence. MDL 11,939 (0.5 mg/kg, i.p.) prevented naloxone-precipitated withdrawal in morphine-dependent mice on day 7. Moreover, chronic morphine treatment increased 5-HT2AR protein level and decreased the phosphorylation of extracellular signal-regulated kinases in the prefrontal cortex. Together, these results by the first time demonstrate that 5-HT2ARs modulate opioid dependence and blockade of 5-HT2AR may represent a novel strategy for the treatment of morphine use disorders. Highlights (i) Blockade of 5-HT2A receptors suppresses the expression of morphine-induced behavioral sensitization. (ii) Blockade of 5-HT2A receptors suppresses naloxone-precipitated withdrawal in morphine-treated mice. (iii) Chronic morphine exposure induces an increase in 5-HT2A receptor protein level and a decrease in ERK protein phosphorylation in prefrontal cortex.
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- 2016
27. Noninvasive assessment of breast cancer molecular subtypes on multiparametric MRI using convolutional neural network with transfer learning
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Haolin Yin, Lutian Bai, Huihui Jia, and Guangwu Lin
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breast cancer ,breast MRI ,deep learning ,molecular subtypes ,neural network ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background To evaluate the performances of multiparametric MRI‐based convolutional neural networks (CNNs) for the preoperative assessment of breast cancer molecular subtypes. Methods A total of 136 patients with 136 pathologically confirmed invasive breast cancers were randomly divided into training, validation, and testing sets in this retrospective study. The CNN models were established based on contrast‐enhanced T1‐weighted imaging (T1C), Apparent diffusion coefficient (ADC), and T2‐weighted imaging (T2W) using the training and validation sets. The performances of CNN models were evaluated on the testing set. The area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy were calculated to assess the performance. Results For the separation of each subtype from other subtypes on the testing set, the T1C‐based models yielded AUCs from 0.762 to 0.920; the ADC‐based models yielded AUCs from 0.686 to 0.851; and the T2W‐based models achieved AUCs from 0.639 to 0.697. Conclusion T1C‐based models performed better than ADC‐based models and T2W‐based models in assessing the breast cancer molecular subtypes. The discriminating performances of our CNN models for triple negative and human epidermal growth factor receptor 2‐enriched subtypes were better than that of luminal A and luminal B subtypes.
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- 2022
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28. Nucleic acid direct delivery to fibroblasts: a review of nucleofection and applications
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Ranyue Ren, Jiachao Guo, Guangwu Liu, Hao Kang, Hans-Günther Machens, Arndt F. Schilling, Alex Slobodianski, and Ziyang Zhang
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Nucleofection ,Fibroblasts ,Gene therapy ,Transfection efficiency ,Clinical applications ,Biology (General) ,QH301-705.5 - Abstract
Abstract The fibroblast is one of the ideal target cell candidates for cell-based gene therapy approaches to promote tissue repair. Gene delivery to fibroblasts by viral transfection has been confirmed to have high transfection efficiency. However, in addition to immunogenic effects of viruses, the random integration of viral genes may damage the genome, affect the cell phenotype or even cause cancerous mutations in the transfected cells. Due to these potential biohazards and unknown long-term risks, the clinical use of viral transfection has been very limited. In contrast, initial non-viral transfection methods have been simple and safe to implement, with low immunogenicity, insertional mutagenesis, and risk of carcinogenesis, but their transfection efficiency has been relatively low. Nucleofection, a more recent non-viral transfection method, now combines the advantages of high transfection efficiency and direct nucleic acid delivery to the nucleus with a high safety. Here, we reviewed recent articles on fibroblast nucleofection, summarized different research points, improved methods and application scopes, and opened up ideas for promoting the further improvement and development of fibroblast nucleofection to meet the needs of a variety of disease research and clinical applications.
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- 2022
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29. Correlations of neutron multiplicity andγ-ray multiplicity with fragment mass and total kinetic energy in spontaneous fission ofCf252
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Jørgen Randrup, Taofeng Wang, Liping Zhu, Long Hou, Haihong Xia, Wenhui Zhang, Hongyin Han, Liming Wang, Ramona Vogt, Guangwu Li, and Qinghua Meng
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Physics ,010308 nuclear & particles physics ,Astrophysics::High Energy Astrophysical Phenomena ,Multiplicity (mathematics) ,Neutron multiplicity ,Kinetic energy ,01 natural sciences ,Nuclear physics ,0103 physical sciences ,Neutron ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Spontaneous fission - Abstract
The dependence of correlations of neutron multiplicity $\ensuremath{\nu}$ and $\ensuremath{\gamma}$-ray multiplicity ${M}_{\ensuremath{\gamma}}$ in spontaneous fission of $^{252}\mathrm{Cf}$ on fragment mass ${A}^{*}$ and total kinetic energy (TKE) have been investigated by employing the ratio of ${M}_{\ensuremath{\gamma}}/\ensuremath{\nu}$ and the form of ${M}_{\ensuremath{\gamma}}(\ensuremath{\nu})$. We show for the first time that ${M}_{\ensuremath{\gamma}}$ and $\ensuremath{\nu}$ have a complex correlation for heavy fragment masses, while there is a positive dependence of ${M}_{\ensuremath{\gamma}}$ for light fragment masses and for near-symmetric mass splits. The ratio ${M}_{\ensuremath{\gamma}}/\ensuremath{\nu}$ exhibits strong shell effects for neutron magic number $N=50$ and near doubly magic number shell closure at $Z=50$ and $N=82$. The $\ensuremath{\gamma}$-ray multiplicity ${M}_{\ensuremath{\gamma}}$ has a maximum for $\text{TKE}=165--170$ MeV. Above 170 MeV ${M}_{\ensuremath{\gamma}}$(TKE) is approximately linear, while it deviates significantly from a linear dependence at lower TKE. The correlation between the average neutron and $\ensuremath{\gamma}$-ray multiplicities can be partly reproduced by model calculations.
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- 2016
30. Description of the phase transitions of cuprous iodide
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Shunquan Liu, Yu Shan, Changsheng Wang, Guang Tian, Guangwu Li, Jingzhi Han, Yingchang Yang, and Honglin Du
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chemistry.chemical_classification ,Diffraction ,Phase transition ,Mechanical Engineering ,Iodide ,Metals and Alloys ,Space group ,Crystal structure ,Crystallography ,chemistry ,Mechanics of Materials ,Phase (matter) ,X-ray crystallography ,Materials Chemistry ,Diffractometer - Abstract
The phase structures and the phase transition temperatures among α, β and γ phases of CuI have been studied by using X-ray diffractometer with high-temperature camera. The phase transition temperatures are found to be obviously lower than the previous results. And the X-ray diffraction results have allowed the refined structure for β-CuI to be determined in space group R-3m, with Cu + in 6(c) sites and I − in 3(a) and 3(b) sites, which is different from other reports and has been approved to be a transient phase in other articles. The results are also discussed and attributed to the pressure effect.
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- 2009
31. Decreased default mode network functional connectivity with visual processing regions as potential biomarkers for delayed neurocognitive recovery: A resting-state fMRI study and machine-learning analysis
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Zhaoshun Jiang, Yuxi Cai, Songbin Liu, Pei Ye, Yifeng Yang, Guangwu Lin, Shihong Li, Yan Xu, Yangjing Zheng, Zhijun Bao, Shengdong Nie, and Weidong Gu
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whole-brain functional connectivity ,default mode network ,delayed neurocognitive recovery ,machine learning ,visual processing ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
ObjectivesThe abnormal functional connectivity (FC) pattern of default mode network (DMN) may be key markers for early identification of various cognitive disorders. However, the whole-brain FC changes of DMN in delayed neurocognitive recovery (DNR) are still unclear. Our study was aimed at exploring the whole-brain FC patterns of all regions in DMN and the potential features as biomarkers for the prediction of DNR using machine-learning algorithms.MethodsResting-state functional magnetic resonance imaging (fMRI) was conducted before surgery on 74 patients undergoing non-cardiac surgery. Seed-based whole-brain FC with 18 core regions located in the DMN was performed, and FC features that were statistically different between the DNR and non-DNR patients after false discovery correction were extracted. Afterward, based on the extracted FC features, machine-learning algorithms such as support vector machine, logistic regression, decision tree, and random forest were established to recognize DNR. The machine learning experiment procedure mainly included three following steps: feature standardization, parameter adjustment, and performance comparison. Finally, independent testing was conducted to validate the established prediction model. The algorithm performance was evaluated by a permutation test.ResultsWe found significantly decreased DMN connectivity with the brain regions involved in visual processing in DNR patients than in non-DNR patients. The best result was obtained from the random forest algorithm based on the 20 decision trees (estimators). The random forest model achieved the accuracy, sensitivity, and specificity of 84.0, 63.1, and 89.5%, respectively. The area under the receiver operating characteristic curve of the classifier reached 86.4%. The feature that contributed the most to the random forest model was the FC between the left retrosplenial cortex/posterior cingulate cortex and left precuneus.ConclusionThe decreased FC of DMN with regions involved in visual processing might be effective markers for the prediction of DNR and could provide new insights into the neural mechanisms of DNR.Clinical Trial Registration: Chinese Clinical Trial Registry, ChiCTR-DCD-15006096.
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- 2023
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32. Simulation of Energy-Range Relation for Protons Impacting on N-4 Nuclear Emulsion
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Weiping Wen and Guangwu Li
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Physics ,Nuclear physics ,Range (particle radiation) ,Proton ,Plane (geometry) ,Emulsion ,Monte Carlo method ,Curve fitting ,Nuclear emulsion ,Nuclear Experiment ,Energy (signal processing) ,Computational physics - Abstract
Therelationship between the energy of a high-speed proton when impacting onthe N-4 nuclear emulsion plane perpendicularlyand its range in the emulsion was investigated using classical SRIMMonte Carlo programand curve fitting method. A definite analytic expression was derived from this simulation with satisfactory residuals. This resulthas its significance for the prediction of experiments.
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- 2015
33. Magnetic resonance imaging investigation of age‐related morphological changes in the pancreases of 226 Chinese
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Lu Wang, Huihui Jia, Guangwu Lin, and Songbai Zheng
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aging ,magnetic resonance imaging ,pancreas ,Geriatrics ,RC952-954.6 - Abstract
Abstract Objective To investigate the morphological changes with age in the pancreases of healthy individuals undergoing magnetic resonance imaging (MRI). Methods The participants were selected from adults who were undergoing physical examinations from January 2017 to September 2020 at Huadong Hospital. They were divided according to age, as broken down by decades into seven groups ranging from 20 to 29 years to ≥80 years of age. There were 30 to 35 cases for each decade. They were then divided into a young and middle‐aged group (
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- 2021
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34. Experimental Research on the Stiffness Step between the Main Hull and Superstructure of Cruise Ships
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Zhiyong Pei, Bin Yang, Guangwu Liu, and Weiguo Wu
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cruise ships ,superstructure ,stiffness step ,experimental analysis ,structural response ,Naval architecture. Shipbuilding. Marine engineering ,VM1-989 ,Oceanography ,GC1-1581 - Abstract
The demand for larger passenger capacity and more entertainment facilities has led to the rapid growth of the cruise tourism market. The superstructure of cruise ships is designed to be plumper, with numerous decks and complex structural forms. To control the weight and the center of gravity, the bending stiffness of the superstructure is always designed to be weaker than that of the main hull, resulting in a stiffness step. Currently, there is no satisfactory method to accurately estimate the influence of the stiffness step between the main hull and superstructure on the structural response of cruise ships. In the present research, an experimental analysis is conducted to investigate the stiffness step between the main hull and superstructure of a typical cruise ship. By comparing the longitudinal stress distribution characteristics with and without the stiffness step with the theoretical results, the influence of the stiffness step on the longitudinal strength is investigated. Furthermore, the maximum stress and the bending efficiency of the superstructure are also discussed. The present research is of reference significance for the structural safety and reliability design of cruise ships.
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- 2023
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35. Vanillin-induced amelioration of depression-like behaviors in rats by modulating monoamine neurotransmitters in the brain
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Hui Xu, Haihui He, Guangwu Li, Jinyong Xu, and Yang Liu
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Chronic unpredictable mild stress ,Olfactory system ,Male ,medicine.medical_specialty ,Aromatherapy ,Serotonin ,Dopamine ,Emotions ,Major depressive disorder ,Olfaction ,Ultrahigh performance liquid chromatography ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Internal medicine ,medicine ,Animals ,Chronic stress ,Neurotransmitter ,Biological Psychiatry ,Fluoxetine ,Depressive Disorder, Major ,Depression ,Olfactory Pathways ,Olfactory Bulb ,Rats ,Smell ,Psychiatry and Mental health ,Disease Models, Animal ,Endocrinology ,medicine.anatomical_structure ,Monoamine neurotransmitter ,chemistry ,Benzaldehydes ,Olfactory pathway ,Sensory Deprivation ,Corticosterone ,Psychology ,Arousal ,Hypothalamic–pituitary–adrenal axis ,medicine.drug - Abstract
Olfaction plays an important role in emotions in our daily life. Pleasant odors are known to evoke positive emotions, inducing relaxation and calmness. The beneficial effects of vanillin on depressive model rats were investigated using a combination of behavioral assessments and neurotransmitter measurements. Before and after chronic stress condition (or olfactory bulbectomy), and at the end of vanillin or fluoxetine treatment, body weight, immobility time on the forced swimming test and sucrose consumption in the sucrose consumption test were measured. Changes in these assessments revealed the characteristic phenotypes of depression in rats. Neurotransmitters were measured using ultrahigh-performance liquid chromatography. Our results indicated that vanillin could alleviate depressive symptoms in the rat model of chronic depression via the olfactory pathway. Preliminary analysis of the monoamine neurotransmitters revealed that vanillin elevated both serotonin and dopamine levels in brain tissue. These results provide important mechanistic insights into the protective effect of vanillin against chronic depressive disorder via olfactory pathway. This suggests that vanillin may be a potential pharmacological agent for the treatment of major depressive disorder.
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- 2014
36. Multimodel magnetic resonance imaging of mass-forming autoimmune pancreatitis: differential diagnosis with pancreatic ductal adenocarcinoma
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Huihui Jia, Jialin Li, Wenjun Huang, and Guangwu Lin
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Magnetic resonance imaging ,Autoimmune pancreatitis ,Pancreatic ductal adenocarcinoma ,Diffusion-weighted imaging ,Medical technology ,R855-855.5 - Abstract
Abstract Purpose To assess the value of the multimodel magnetic resonance imaging (MRI), including unenhanced images, dynamic contrast-enhanced MRI (DCE-MRI), MR-cholangiopancreatography (MRCP), and diffusion-weighted imaging (DWI), in differentiation of mass-forming autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC). Methods Twelve patients with mass-forming AIP and 30 with PDAC were included. All patients underwent unenhanced MRI, DCE-MRI, DWI, and MRCP. Relevant values including sensitivity and specificity of the imaging features and their diagnostic performance for predicting mass-forming AIP were analyzed. Results Several statistically significant MR findings and quantitative indexes differentiating mass-forming AIP from PDAC, including multiplicity, irregularity or conformation, capsule-like rim enhancement, absence of internal cystic or necrotic portion, homogeneous enhancement during pancreatic, venous, and delayed phases, skipped stricture or stricture of MPD, absence of side branch dilation, maximum upstream MPD diameter 0.739, ContrastAP > 0.710, ContrastPP > 0.879, and ContrastVP or ContrastDP > 0.949, indicated mass-forming AIP (P
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- 2021
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37. Preoperative and Noninvasive Prediction of Gliomas Histopathological Grades and IDH Molecular Types Using Multiple MRI Characteristics
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Ningfang Du, Xiaotao Zhou, Renling Mao, Weiquan Shu, Li Xiao, Yao Ye, Xinxin Xu, Yilang Shen, Guangwu Lin, Xuhao Fang, and Shihong Li
- Subjects
glioma ,magnetic resonance imaging ,isocitrate dehydrogenase ,diffusion-weighted magnetic resonance imaging ,apparent diffusion coefficient ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background and PurposeGliomas are one of the most common tumors in the central nervous system. This study aimed to explore the correlation between MRI morphological characteristics, apparent diffusion coefficient (ADC) parameters and pathological grades, as well as IDH gene phenotypes of gliomas.MethodsPreoperative MRI data from 166 glioma patients with pathological confirmation were retrospectively analyzed to compare the differences of MRI characteristics and ADC parameters between the low-grade and high-grade gliomas (LGGs vs. HGGs), IDH mutant and wild-type gliomas (IDHmut vs. IDHwt). Multivariate models were constructed to predict the pathological grades and IDH gene phenotypes of gliomas and the performance was assessed by the receiver operating characteristic (ROC) analysis.ResultsTwo multivariable logistic regression models were developed by incorporating age, ADC parameters, and MRI morphological characteristics to predict pathological grades, and IDH gene phenotypes of gliomas, respectively. The Noninvasive Grading Model classified tumor grades with areas under the ROC curve (AUROC) of 0.934 (95% CI=0.895-0.973), sensitivity of 91.2%, and specificity of 78.6%. The Noninvasive IDH Genotyping Model differentiated IDH types with an AUROC of 0.857 (95% CI=0.787-0.926), sensitivity of 88.2%, and specificity of 63.8%.ConclusionMRI features were correlated with glioma grades and IDH mutation status. Multivariable logistic regression models combined with MRI morphological characteristics and ADC parameters may provide a noninvasive and preoperative approach to predict glioma grades and IDH mutation status.
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- 2022
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38. Intravoxel Incoherent Motion Magnetic Resonance Imaging Used in Preoperative Screening of High-Risk Patients With Moyamoya Disease Who May Develop Postoperative Cerebral Hyperperfusion Syndrome
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Feng Gao, Wei Zhao, Yu Zheng, Yu Duan, Ming Ji, Guangwu Lin, and Zhenfang Zhu
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moyamoya disease ,perfusion imaging ,magnetic resonance imaging ,microvascular circulation ,surgery ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
ObjectiveThis study aimed to investigate the feasibility of preoperative intravoxel incoherent motion (IVIM) MRI for the screening of high-risk patients with moyamoya disease (MMD) who may develop postoperative cerebral hyperperfusion syndrome (CHS).MethodsThis study composed of two parts. In the first part 24 MMD patients and 24 control volunteers were enrolled. IVIM-MRI was performed. The relative pseudo-diffusion coefficient, perfusion fraction, apparent diffusion coefficient, and diffusion coefficient (rD*, rf, rADC, and rD) values of the IVIM sequence were compared according to hemispheres between MMD patient and healthy control groups. In the second part, 98 adult patients (124 operated hemispheres) with MMD who underwent surgery were included. Preoperative IVIM-MRI was performed. The rD*, rf, rADC, rD, and rfD* values of the IVIM sequence were calculated and analyzed. Operated hemispheres were divided into CHS and non-CHS groups. Patients’ age, sex, Matsushima type, Suzuki stage, and IVIM-MRI examination results were compared between CHS and non-CHS groups.ResultsOnly the rf value was significantly higher in the healthy control group than in the MMD group (P < 0.05). Out of 124 operated hemispheres, 27 were assigned to the CHS group. Patients with clinical presentation of Matsushima types I–V were more likely to develop CHS after surgery (P < 0.05). The rf values of the ipsilateral hemisphere were significantly higher in the CHS group than in the non-CHS group (P < 0.05). The rfD* values of the ACA and MCA supply areas of the ipsilateral hemisphere were significantly higher in the CHS group than in the non-CHS group (P < 0.05). Only the rf value of the anterior cerebral artery supply area in the contralateral hemisphere was higher in the CHS group than in the non-CHS group (P < 0.05). The rf values of the middle and posterior cerebral artery supply areas and the rD, rD*, and rADC values of the both hemispheres were not significantly different between the CHS and non-CHS groups (P > 0.05).ConclusionPreoperative non-invasive IVIM-MRI analysis, particularly the f-value of the ipsilateral hemisphere, may be helpful in predicting CHS in adult patients with MMD after surgery. MMD patients with ischemic onset symptoms are more likely to develop CHS after surgery.
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- 2022
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39. A Formation Control Method for AUV Group Under Communication Delay
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Yuepeng Chen, Xuan Guo, Guangyu Luo, and Guangwu Liu
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heterogeneous AUV group ,consistency algorithm ,leader–follower ,communication delay ,graph theory ,Biotechnology ,TP248.13-248.65 - Abstract
This article presents a consistency control algorithm for the autonomous underwater vehicle (AUV) group combined with the leader–follower approach under communication delay. First, the six-degree-of-freedom (DoF) model of AUV is represented, and the graph theory is used to describe the communication topology of the AUV group. Especially, a hybrid communication topology is introduced to adapt to large formation control. Second, the distributed control law is constructed by combining the consensus theory with the leader–follower method. The consistency control algorithms for homogeneous and heterogeneous AUV groups based on the leader–follower approach under communication delay are proposed. Stability criteria are established to guarantee the consensus based on the Gershgorin disk theorem and Nyquist law, respectively. Finally, numerous simulation experiments are carried out to show the effectiveness and superiority of the proposed algorithms.
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- 2022
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40. Non-Invasive Evaluation of Cerebral Hemodynamic Changes After Surgery in Adult Patients With Moyamoya Using 2D Phase-Contrast and Intravoxel Incoherent Motion MRI
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Feng Gao, Wei Zhao, Yu Zheng, Shihong Li, Yu Duan, Zhenfang Zhu, Ming Ji, Jun Liu, and Guangwu Lin
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moyamoya disease ,intravoxel incoherent motion ,phase-contrast MRI ,Suzuki stage ,surgery ,Surgery ,RD1-811 - Abstract
ObjectiveTo explore the feasibility of 2D phase-contrast MRI (PC-MRI) and intravoxel incoherent motion (IVIM) MRI to assess cerebrovascular hemodynamic changes after surgery in adult patients with moyamoya disease (MMD).MethodsIn total, 33 patients with MMD who underwent 2D PC-MRI and IVIM examinations before and after surgery were enrolled. Postsurgical changes in peak and average velocities, average flow, forward volume, and the area of superficial temporal (STA), internal carotid (ICA), external carotid (ECA), and vertebral (VA) arteries were evaluated. The microvascular perfusion status was compared between the hemorrhage and non-hemorrhage groups.ResultsThe peak velocity, average flow, forward volume, area of both the ipsilateral STA and ECA, and average velocity of the ipsilateral STA were increased (p < 0.05). The average flow and forward volume of both the ipsilateral ICA and VA and the area of the ipsilateral VA were increased (p < 0.05). The peak velocity, average velocity, average flow and forward volume of the contralateral STA, and the area of the contralateral ICA and ECA were also increased (p < 0.05), whereas the area of the contralateral VA was decreased (p < 0.05). The rf value of the ipsilateral anterior cerebral artery (ACA) supply area was increased (p < 0.05) and more obvious in the non-hemorrhage group (p < 0.05).ConclusionTwo-dimensional PC-MRI and IVIM may have the potential to non-invasively evaluate cerebrovascular hemodynamic changes after surgery in patients with MMD. An improvement in the microvascular perfusion status is more obvious in patients with ischemic MMD than in patients with hemorrhagic MMD.
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- 2022
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41. Shunt Surgery Efficacy Is Correlated With Baseline Cerebrum Perfusion in Idiopathic Normal Pressure Hydrocephalus: A 3D Pulsed Arterial-Spin Labeling Study
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Wenjun Huang, Xuhao Fang, Shihong Li, Renling Mao, Chuntao Ye, Wei Liu, and Guangwu Lin
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idiopathic normal pressure hydrocephalus (INPH) ,pulsed arterial-spin labeling (PASL) ,neuroimaging ,dementia ,gait disorder ,incontinence ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
This study investigated the relationship between preoperative cerebral blood flow (CBF) in patients with idiopathic normal pressure hydrocephalus (INPH) and preoperative clinical symptoms and changes of clinical symptoms after shunt surgery. A total of 32 patients with diagnosed INPH and 18 age-matched healthy controls (HCs) were involved in this study. All subjects underwent magnetic resonance imaging (MRI), including 3D pulsed arterial-spin labeling (PASL) for non-invasive perfusion imaging, and clinical symptom evaluation at baseline, and all patients with INPH were reexamined with clinical tests 1 month postoperatively. Patients with INPH had significantly lower whole-brain CBF than HCs, with the most significant differences in the high convexity, temporal lobe, precuneus, and thalamus. At baseline, there was a significant correlation between the CBF in the middle frontal gyrus, calcarine, inferior and middle temporal gyrus, thalamus, and posterior cingulate gyrus and poor gait manifestation. After shunting, improvements were negatively correlated with preoperative perfusion in the inferior parietal gyrus, inferior occipital gyrus, and middle temporal gyrus. Preoperative CBF in the middle frontal gyrus was positively correlated with the severity of preoperative cognitive impairment and negatively correlated with the change of postoperative MMSE score. There was a moderate positive correlation between anterior cingulate hypoperfusion and improved postoperative urination. Our study revealed that widely distributed and intercorrelated cortical and subcortical pathways are involved in the development of INPH symptoms, and preoperative CBF may be correlative to short-term shunt outcomes.
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- 2022
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42. Apparent Diffusion Coefficient-Based Convolutional Neural Network Model Can Be Better Than Sole Diffusion-Weighted Magnetic Resonance Imaging to Improve the Differentiation of Invasive Breast Cancer From Breast Ductal Carcinoma In Situ
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Haolin Yin, Yu Jiang, Zihan Xu, Wenjun Huang, Tianwu Chen, and Guangwu Lin
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breast cancer ,ductal carcinoma in situ ,diffusion-weighted imaging ,magnetic resonance imaging ,deep learning ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background and PurposeBreast ductal carcinoma in situ (DCIS) has no metastatic potential, and has better clinical outcomes compared with invasive breast cancer (IBC). Convolutional neural networks (CNNs) can adaptively extract features and may achieve higher efficiency in apparent diffusion coefficient (ADC)-based tumor invasion assessment. This study aimed to determine the feasibility of constructing an ADC-based CNN model to discriminate DCIS from IBC.MethodsThe study retrospectively enrolled 700 patients with primary breast cancer between March 2006 and June 2019 from our hospital, and randomly selected 560 patients as the training and validation sets (ratio of 3 to 1), and 140 patients as the internal test set. An independent external test set of 102 patients during July 2019 and May 2021 from a different scanner of our hospital was selected as the primary cohort using the same criteria. In each set, the status of tumor invasion was confirmed by pathologic examination. The CNN model was constructed to discriminate DCIS from IBC using the training and validation sets. The CNN model was evaluated using the internal and external tests, and compared with the discriminating performance using the mean ADC. The area under the curve (AUC), sensitivity, specificity, and accuracy were calculated to evaluate the performance of the previous model.ResultsThe AUCs of the ADC-based CNN model using the internal and external test sets were larger than those of the mean ADC (AUC: 0.977 vs. 0.866, P = 0.001; and 0.926 vs. 0.845, P = 0.096, respectively). Regarding the internal test set and external test set, the ADC-based CNN model yielded sensitivities of 0.893 and 0.873, specificities of 0.929 and 0.894, and accuracies of 0.907 and 0.902, respectively. Regarding the two test sets, the mean ADC showed sensitivities of 0.845 and 0.818, specificities of 0.821 and 0.829, and accuracies of 0.836 and 0.824, respectively. Using the ADC-based CNN model, the prediction only takes approximately one second for a single lesion.ConclusionThe ADC-based CNN model can improve the differentiation of IBC from DCIS with higher accuracy and less time.
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- 2022
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43. On Curvilinear Regression Analysis via Newly Proposed Entropies for Some Benzene Models
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Guangwu Liu, Muhammad Kamran Siddiqui, Shazia Manzoor, Muhammad Naeem, and Douhadji Abalo
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Electronic computers. Computer science ,QA75.5-76.95 - Abstract
To avoid exorbitant and extensive laboratory experiments, QSPR analysis, based on topological descriptors, is a very constructive statistical approach for analyzing the numerous physical and chemical properties of compounds. Therefore, we presented some new entropy measures which are based on the sum of the neighborhood degree of the vertices. Firstly, we made the partition of the edges of benzene derivatives which are based on the degree sum of neighboring vertices and then computed the neighborhood version of entropies. Secondly, we made use of the software SPSS for developing a correlation between newly introduced entropies and the physicochemical properties of benzene derivatives. Our obtained results demonstrated that the critical temperature CT, critical pressure CP, and critical volume CV can be predicted through fifth geometric arithmetic entropy, second SK entropy, and fifth ND entropy, respectively. Other remaining physical characteristics include Gibb’s energy qℰ, logP, molar refractivity ℳℛ, and Henry’s law ℋℒ that can be predicted by using sixth ND entropy.
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- 2022
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44. Blockade of Serotonin 5-HT2A Receptors Suppresses Behavioral Sensitization and Naloxone-Precipitated Withdrawal Symptoms in Morphine-Treated Mice.
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Gang Pang, Xian Wu, Xinrong Tao, Ruoying Mao, Xueke Liu, Yong-Mei Zhang, Guangwu Li, Stackman Jr., Robert W., Liuyi Dong, and Gongliang Zhang
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SEROTONIN ,NALOXONE ,MORPHINE - Abstract
The increasing prescription of opioids is fueling an epidemic of addiction and overdose deaths. Morphine is a highly addictive drug characterized by a high relapse rate -- even after a long period of abstinence. Serotonin (5-HT) neurotransmission participates in the development of morphine dependence, as well as the expression of morphine withdrawal. In this study, we examined the effect of blockade of 5-HT
2A receptors (5-HT2A Rs) on morphine-induced behavioral sensitization and withdrawal in male mice. 5-HT2A R antagonist MDL 11,939 (0.5 mg/kg, i.p.) suppressed acute morphine (5.0 mg/kg, s.c.)-induced increase in locomotor activity. Mice received morphine (10 mg/kg, s.c.) twice a day for 3 days and then drug treatment was suspended for 5 days. On day 9, a challenge dose of morphine (10 mg/kg) was administered to induce the expression of behavioral sensitization. MDL 11,939 (0.5 mg/kg, i.p.) pretreatment suppressed the expression of morphine-induced behavioral sensitization. Another cohort of mice received increasing doses of morphine over a 7-day period to induce morphine-dependence. MDL 11,939 (0.5 mg/kg, i.p.) prevented naloxone-precipitated withdrawal in morphine-dependent mice on day 7. Moreover, chronic morphine treatment increased 5-HT 2AR protein level and decreased the phosphorylation of extracellular signal-regulated kinases in the prefrontal cortex. Together, these results by the first time demonstrate that 5-HT2A Rs modulate opioid dependence and blockade of 5-HT2A R may represent a novel strategy for the treatment of morphine use disorders. [ABSTRACT FROM AUTHOR]- Published
- 2016
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45. Preliminary Exploration of the Sequence of Nerve Fiber Bundles Involvement for Idiopathic Normal Pressure Hydrocephalus: A Correlation Analysis Using Diffusion Tensor Imaging
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Wenjun Huang, Xuhao Fang, Shihong Li, Renling Mao, Chuntao Ye, Wei Liu, and Guangwu Lin
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idiopathic normal pressure hydrocephalus (INPH) ,diffusion tensor imaging (DTI) ,white matter (WM) ,central gray matter ,dementia ,gait disorder ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
The study preliminarily explored the sequence and difference of involvement in different neuroanatomical structures in idiopathic normal pressure hydrocephalus (INPH). We retrospectively analyzed the differences in diffusion tensor imaging (DTI) parameters in 15 ROIs [including the bilateral centrum semiovale (CS), corpus callosum (CC) (body, genu, and splenium), head of the caudate nucleus (CN), internal capsule (IC) (anterior and posterior limb), thalamus (TH), and the bilateral frontal horn white matter hyperintensity (FHWMH)] between 27 INPH patients and 11 healthy controls and the correlation between DTI indices and clinical symptoms, as evaluated by the INPH grading scale (INPHGS), the Mini-Mental State Examination (MMSE), and the timed up and go test (TUG-t), before and 1 month after shunt surgery. Significant differences were observed in DTI parameters from the CS (pFA1 = 0.004, pADC1 = 0.005) and the genu (pFA2 = 0.022; pADC2 = 0.001) and body (pFA3 = 0.003; pADC3 = 0.002) of the CC between the groups. The DTI parameters from the CS were strongly correlated with the MMSE score both pre-operatively and post-operatively. There was association between apparent diffusion coefficient (ADC) values of anterior and posterior limbs of the IC and MMSE. The DTI parameters of the head of the CN were correlated with motion, and the ADC value was significantly associated with the MMSE score. The FA value from TH correlated with an improvement in urination after shunt surgery. We considered that different neuroanatomical structures are affected differently by disease due to their positions in neural pathways and characteristics, which is further reflected in clinical symptoms and the prognosis of shunt surgery.
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- 2021
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46. Predicting Delayed Neurocognitive Recovery After Non-cardiac Surgery Using Resting-State Brain Network Patterns Combined With Machine Learning
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Zhaoshun Jiang, Yuxi Cai, Xixue Zhang, Yating Lv, Mengting Zhang, Shihong Li, Guangwu Lin, Zhijun Bao, Songbin Liu, and Weidong Gu
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delayed neurocognitive recovery ,default mode network ,functional connectivity ,machine learning ,resting-state functional MRI ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Delayed neurocognitive recovery (DNR) is a common subtype of postoperative neurocognitive disorders. An objective approach for identifying subjects at high risk of DNR is yet lacking. The present study aimed to predict DNR using the machine learning method based on multiple cognitive-related brain network features. A total of 74 elderly patients (≥ 60-years-old) undergoing non-cardiac surgery were subjected to resting-state functional magnetic resonance imaging (rs-fMRI) before the surgery. Seed-based whole-brain functional connectivity (FC) was analyzed with 18 regions of interest (ROIs) located in the default mode network (DMN), limbic network, salience network (SN), and central executive network (CEN). Multiple machine learning models (support vector machine, decision tree, and random forest) were constructed to recognize the DNR based on FC network features. The experiment has three parts, including performance comparison, feature screening, and parameter adjustment. Then, the model with the best predictive efficacy for DNR was identified. Finally, independent testing was conducted to validate the established predictive model. Compared to the non-DNR group, the DNR group exhibited aberrant whole-brain FC in seven ROIs, including the right posterior cingulate cortex, right medial prefrontal cortex, and left lateral parietal cortex in the DMN, the right insula in the SN, the left anterior prefrontal cortex in the CEN, and the left ventral hippocampus and left amygdala in the limbic network. The machine learning experimental results identified a random forest model combined with FC features of DMN and CEN as the best prediction model. The area under the curve was 0.958 (accuracy = 0.935, precision = 0.899, recall = 0.900, F1 = 0.890) on the test set. Thus, the current study indicated that the random forest machine learning model based on rs-FC features of DMN and CEN predicts the DNR following non-cardiac surgery, which could be beneficial to the early prevention of DNR.Clinical Trial Registration: The study was registered at the Chinese Clinical Trial Registry (Identification number: ChiCTR-DCD-15006096).
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- 2021
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47. Multi-Order Brain Functional Connectivity Network-Based Machine Learning Method for Recognition of Delayed Neurocognitive Recovery in Older Adults Undergoing Non-cardiac Surgery
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Guoqing Wu, Zhaoshun Jiang, Yuxi Cai, Xixue Zhang, Yating Lv, Shihong Li, Guangwu Lin, Zhijun Bao, Songbin Liu, and Weidong Gu
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delayed neurocognitive recovery ,resting-state functional magnetic resonance imaging ,functional connectivity ,machine learning ,sparse representation ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Objectives: Delayed neurocognitive recovery (DNR) seriously affects the post-operative recovery of elderly surgical patients, but there is still a lack of effective methods to recognize high-risk patients with DNR. This study proposed a machine learning method based on a multi-order brain functional connectivity (FC) network to recognize DNR.Method: Seventy-four patients who completed assessments were included in this study, in which 16/74 (21.6%) had DNR following surgery. Based on resting-state functional magnetic resonance imaging (rs-fMRI), we first constructed low-order FC networks of 90 brain regions by calculating the correlation of brain region signal changing in the time dimension. Then, we established high-order FC networks by calculating correlations among each pair of brain regions. Afterward, we built sparse representation-based machine learning model to recognize DNR on the extracted multi-order FC network features. Finally, an independent testing was conducted to validate the established recognition model.Results: Three hundred ninety features of FC networks were finally extracted to identify DNR. After performing the independent-sample T test between these features and the categories, 15 features showed statistical differences (P < 0.05) and 3 features had significant statistical differences (P < 0.01). By comparing DNR and non-DNR patients’ brain region connection matrices, it is found that there are more connections among brain regions in DNR patients than in non-DNR patients. For the machine learning recognition model based on multi-feature combination, the area under the receiver operating characteristic curve (AUC), accuracy, sensitivity, and specificity of the classifier reached 95.61, 92.00, 66.67, and 100.00%, respectively.Conclusion: This study not only reveals the significance of preoperative rs-fMRI in recognizing post-operative DNR in elderly patients but also establishes a promising machine learning method to recognize DNR.
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- 2021
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48. Aberrant Resting-State Functional Connectivity of the Dorsal Attention Network in Tinnitus
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Haimeng Hu, Yining Lyu, Shihong Li, Zheng Yuan, Chuntao Ye, Zhao Han, and Guangwu Lin
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Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Previous functional magnetic resonance imaging (fMRI) analyses have shown that the dorsal attention network (DAN) is involved in the pathophysiological changes of tinnitus, but few relevant studies have been conducted, and the conclusions to date are not uniform. The purpose of this research was to test whether there is a change in intrinsic functional connectivity (FC) patterns between the DAN and other brain regions in tinnitus patients. Thirty-one patients with persistent tinnitus and thirty-three healthy controls were enrolled in this study. A group independent component analysis (ICA), degree centrality (DC) analysis, and seed-based FC analysis were conducted. In the group ICA, the tinnitus patients showed increased connectivity in the left superior parietal gyrus in the DAN compared to the healthy controls. Compared with the healthy controls, the tinnitus patients showed increased DC in the left inferior parietal gyrus and decreased DC in the left precuneus within the DAN. The clusters within the DAN with significant differences in the ICA or DC analysis between the tinnitus patients and the healthy controls were selected as regions of interest (ROIs) for seeds. The tinnitus patients exhibited significantly increased FC from the left superior parietal gyrus to several brain regions, including the left inferior parietal gyrus, the left superior marginal gyrus, and the right superior frontal gyrus, and decreased FC to the right anterior cingulate cortex. The tinnitus patients exhibited decreased FC from the left precuneus to the left inferior occipital gyrus, left calcarine cortex, and left superior frontal gyrus compared with the healthy controls. The findings of this study show that compared with healthy controls, tinnitus patients have altered functional connections not only within the DAN but also between the DAN and other brain regions. These results suggest that it may be possible to improve the disturbance and influence of tinnitus by regulating the DAN.
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- 2021
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49. Preoperative Altered Spontaneous Brain Activity and Functional Connectivity Were Independent Risk Factors for Delayed Neurocognitive Recovery in Older Adults Undergoing Noncardiac Surgery
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Zhaoshun Jiang, Xixue Zhang, Yating Lv, Xiaodong Zheng, Huibiao Zhang, Xuelin Zhang, Chongyi Jiang, Guangwu Lin, and Weidong Gu
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Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Objectives. Recently, it has been demonstrated that patients with subtle preexisting cognitive impairment were susceptible to delayed neurocognitive recovery (DNR). This present study investigated whether preoperative alterations in gray matter volume, spontaneous activity, or functional connectivity (FC) were associated with DNR. Methods. This was a nested case-control study of older adults (≥60 years) undergoing noncardiac surgery. All patients received MRI scan at least 1 day prior to surgery. Cognitive function was assessed prior to surgery and at 7-14 days postsurgery. Preoperative gray matter volume, amplitude of low-frequency fluctuation (ALFF), and FC were compared between the DNR patients and non-DNR patients. The independent risk factors associated with DNR were identified using a multivariate logistic regression model. Results. Of the 74 patients who completed assessments, 16/74 (21.6%) had DNR following surgery. There were no differences in gray matter volume between the two groups. However, the DNR patients exhibited higher preoperative ALFF in the bilateral middle cingulate cortex (MCC) and left fusiform gyrus and lower preoperative FC between the bilateral MCC and left calcarine than the non-DNR patients. The multivariate logistic regression analysis showed that higher preoperative spontaneous activity in the bilateral MCC was independently associated with a higher risk of DNR (OR=3.11, 95% CI, 1.30-7.45; P=0.011). A longer education duration (OR=0.57, 95% CI, 0.41-0.81; P=0.001) and higher preoperative FC between the bilateral MCC and left calcarine (OR=0.40, 95% CI, 0.18-0.92; P=0.031) were independently correlated with a lower risk of DNR. Conclusions. Preoperative higher ALFF in the bilateral MCC and lower FC between the bilateral MCC and left calcarine were independently associated with the occurrence of DNR. The present fMRI study identified possible preoperative neuroimaging risk factors for DNR. This trial is registered with Chinese Clinical Trial Registry ChiCTR-DCD-15006096.
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- 2020
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50. Premorbid Alterations of Spontaneous Brain Activity in Elderly Patients With Early Post-operative Cognitive Dysfunction: A Pilot Resting-State Functional MRI Study
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Xixue Zhang, Hui Li, Yating Lv, Zhenghong Zhu, Xiaoyong Shen, Qi Lu, Wei Wang, Zhaoxin Wang, Zhaoshun Jiang, Lvjun Yang, Guangwu Lin, and Weidong Gu
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resting-state fMRI ,pre-operative changes in brain ,cognitive decline ,early post-operative period ,functional connectivity ,regional homogeneity ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Background: Elderly patients with pre-existing cognitive impairment are susceptible to post-operative cognitive dysfunction (POCD). In this study, we investigated whether there is pre-existing local homogeneity and functional connectivity alteration in the brain before surgery for POCD patients as compared to that in non-POCD patients.Methods: Eighty elderly patients undergoing major thoracic or abdominal surgeries were recruited. Resting-state functional MRI was scanned at least 1 day before surgery. Neuropsychological tests (NPTs) were performed before surgery and at discharge, respectively. Pre-operative regional homogeneity (ReHo) and resting-state functional connectivity (RSFC) were compared between POCD patients and non-POCD patients, respectively. Partial correlation between NPTs and ReHo or RSFC was analyzed by adjusting for confounding factors.Results: Significant difference (P < 0.001, Gaussian Random Field (GRF) correction which is a multiple comparisons correction method at cluster level, cluster size > 49) in ReHo between POCD patients and non-POCD patients was detected in right hippocampus/parahippocampus. Pre-operative RSFC between right hippocampus/parahippocampus and right middle/inferior temporal gyrus increased in POCD patients (P < 0.001, GRF correction for multiple comparisons) when compared with that in non-POCD patients.RSFC significantly correlated with composite Z-score (r = 0.46, 95% CI [0.234, 0.767], P = 0.002) or Digit Symbol Substitution Test Z-scores (r = 0.31, 95% CI [0.068, 0.643], P = 0.046) after adjusting for confounding factors.Conclusions: The results suggest that premorbid alterations of spontaneous brain activity might exist in elderly patients who develop early POCD. The neural mechanism by which patients with pre-operative abnormal spontaneous activity are susceptible to POCD requires further study.
- Published
- 2019
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