18 results on '"Qian, T."'
Search Results
2. Semantic-enhanced graph neural network for named entity recognition in ancient Chinese books.
- Author
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Xu Y, Mao C, Wang Z, Jin G, Zhong L, and Qian T
- Subjects
- China, Books history, Humans, Deep Learning, Semantics, Neural Networks, Computer
- Abstract
Named entity recognition (NER) plays a crucial role in the extraction and utilization of knowledge of ancient Chinese books. However, the challenges of ancient Chinese NER not only originate from linguistic features such as the use of single characters and short sentences but are also exacerbated by the scarcity of training data. These factors together limit the capability of deep learning models, like BERT-CRF, in capturing the semantic representation of ancient Chinese characters. In this paper, we explore the semantic enhancement of NER in ancient Chinese books through the utilization of external knowledge. We propose a novel model based on Graph Neural Networks that integrates two different forms of external knowledge: dictionary-level and chapter-level information. Through the Graph Attention Mechanism (GAT), these external knowledge are effectively incorporated into the model's input context. Our model is evaluated on the C_CLUE dataset, showing an improvement of 3.82% over the baseline BAC-CRF model. It also achieves the best score compared to several state-of-the-art dictionary-augmented models., (© 2024. The Author(s).)
- Published
- 2024
- Full Text
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3. Activation of Einstein-Podolsky-Rosen steering sharing with unsharp nonlocal measurements.
- Author
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Han XH, Qian T, Dong SC, Wang S, Xiao Y, and Gu YJ
- Abstract
Einstein-Podolsky-Rosen (EPR) steering is commonly shared among multiple observers by utilizing unsharp measurements. Nevertheless, their usage is restricted to local measurements and does not encompass all nonlocal measurement-based cases. In this work, a method for finding beneficial local measurement settings has been expanded to include nonlocal measurement cases. This method is applicable for any bipartite state and offers benefits even in scenarios with a high number of measurement settings. Using the Greenberger-Horne-Zeilinger state as an illustration, we show that employing unsharp nonlocal measurements can activate the phenomenon of steering sharing in contrast to using local measurements. Furthermore, our findings demonstrate that nonlocal measurements with unequal strength possess a greater activation capability compared to those with equal strength. Our activation method generates fresh concepts for conservation and recycling quantum resources., (© 2024. The Author(s).)
- Published
- 2024
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4. Methamphetamine use increases the risk of cerebral small vessel disease in young patients with acute ischemic stroke.
- Author
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Zhu Z, Vanderschelden B, Lee SJ, Blackwill H, Shafie M, Soun JE, Chow D, Chang P, Stradling D, Qian T, and Yu W
- Subjects
- Humans, Male, Magnetic Resonance Imaging, Ischemic Stroke complications, Methamphetamine adverse effects, Cerebral Small Vessel Diseases complications, Cerebral Small Vessel Diseases diagnostic imaging, Stroke etiology, Stroke complications, Hypertension complications
- Abstract
Methamphetamine use causes spikes in blood pressure. Chronic hypertension is a major risk factor for cerebral small vessel disease (cSVD). The aim of this study is to investigate whether methamphetamine use increases the risk of cSVD. Consecutive patients with acute ischemic stroke at our medical center were screened for methamphetamine use and evidence of cSVD on MRI of the brain. Methamphetamine use was identified by self-reported history and/or positive urine drug screen. Propensity score matching was used to select non-methamphetamine controls. Sensitivity analysis was performed to assess the effect of methamphetamine use on cSVD. Among 1369 eligible patients, 61 (4.5%) were identified to have a history of methamphetamine use and/or positive urine drug screen. Compared with the non-methamphetamine group (n = 1306), the patients with methamphetamine abuse were significantly younger (54.5 ± 9.7 vs. 70.5 ± 12.4, p < 0.001), male (78.7% vs. 54.0%, p < 0.001) and White (78.7% vs. 50.4%, p < 0.001). Sensitivity analysis showed that methamphetamine use was associated with increased white matter hyperintensities, lacunes, and total burden of cSVD. The association was independent of age, sex, concomitant cocaine use, hyperlipidemia, acute hypertension, and stroke severity. Our findings suggest that methamphetamine use increases the risk of cSVD in young patients with acute ischemic stroke., (© 2023. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)
- Published
- 2023
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5. Protecting nonlocal quantum correlations in correlated squeezed generalized amplitude damping channel.
- Author
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Wang S, Han XH, Li WC, Qian T, Fan X, Xiao Y, and Gu YJ
- Abstract
Nonlocal quantum correlations, such as quantum entanglement, quantum steering, and Bell nonlocality, are crucial resources for quantum information tasks. How to protect these quantum resources from decoherence is one of the most urgent problems to be solved. Here, we investigate the evolution of these correlations in the correlated squeezed generalized amplitude damping (SGAD) channel and propose a scheme to protect them with weak measurement (WM) and quantum measurement reversal (QMR). Compared with the results of the uncorrelated SGAD channel, we find that when [Formula: see text], correlation and squeezing effects can prolong the survival time of quantum entanglement, Bell nonlocality, and quantum steering by about 152 times, 207 times, and 10 times, respectively. In addition, local WM and QMR can effectively recover the disappeared nonlocal quantum correlations either in uncorrelated or completely correlated SGAD channels. Moreover, we find that these initial nonlocal quantum correlations could be drastically amplified under the correlated channel. And the steering direction can be flexibly manipulated either by changing the channel parameters or the strength of WM and QMR. These results not only make a step forward in suppressing decoherence and enhancing quantum correlation in noise channels, but also help to develop relevant practical applications., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
6. Reduced renal function may explain the higher prevalence of hyperuricemia in older people.
- Author
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Wang Y, Zhang W, Qian T, Sun H, Xu Q, Hou X, Hu W, Zhang G, Drummond GR, Sobey CG, Charchar FJ, Golledge J, and Yang G
- Subjects
- Adult, Age Factors, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Prevalence, Retrospective Studies, Risk Factors, Aging blood, Glomerular Filtration Rate, Hyperuricemia blood, Hyperuricemia epidemiology, Hyperuricemia physiopathology, Kidney metabolism, Kidney physiopathology
- Abstract
This study aimed to investigate the contribution of renal dysfunction to enhanced hyperuricemia prevalence in older people. A cohort of 13,288 Chinese people aged between 40 and 95 years were recruited from January to May 2019. Serum uric acid concentration and estimated glomerular filtration rate [eGFR] were measured. The associations between age or eGFR and serum uric acid or hyperuricemia were analyzed using linear or binary logistic regression adjusting for risk factors. Uric acid concentration and prevalence of hyperuricemia were greater in older participants. Adjustment for reduced renal function (eGFR < 60 mL/min/1.73 m
2 ) eliminated the associations between older age and higher uric acid concentration and between older age and higher prevalence of hyperuricemia diagnosis, whereas adjustment for other risk factors did not change those associations. Lower eGFR was associated with higher uric acid concentration both before (β = - 0.296, P < 0.001) and after adjustment for age (β = - 0.313, P < 0.001). Reduced renal function was associated with hyperuricemia diagnosis both before (odds ratio, OR, 3.64; 95% CI 3.10-4.28; P < 0.001) and after adjustment for age (adjusted OR, 3.82; 95% CI 3.22-4.54; P < 0.001). Mean serum uric acid and prevalence of hyperuricemia were higher in people with eGFR < 60 mL/min/1.73 m2 than those with eGFR ≥ 60 mL/min/1.73 m2 . The prevalence of reduced renal function increased with older age (P < 0.001). This study suggests that reduced renal function can explain the increased uric acid levels and hyperuricemia diagnoses in older people.- Published
- 2021
- Full Text
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7. Restricted immunological and cellular pathways are shared by murine models of chronic alcohol consumption.
- Author
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Vogle A, Qian T, Zhu S, Burnett E, Fey H, Zhu Z, Keshavarzian A, Shaikh M, Hoshida Y, Kim M, and Aloman C
- Subjects
- Alcohol Drinking genetics, Alcohol Drinking immunology, Alcoholism etiology, Alcoholism genetics, Alcoholism immunology, Animals, Chronic Disease, Disease Models, Animal, Female, Humans, Liver immunology, Liver metabolism, Liver Diseases, Alcoholic etiology, Liver Diseases, Alcoholic genetics, Liver Diseases, Alcoholic immunology, Mice, Mice, Inbred C57BL, Transcriptome, Alcohol Drinking pathology, Alcoholism pathology, Liver pathology, Liver Diseases, Alcoholic pathology
- Abstract
Murine models of chronic alcohol consumption are frequently used to investigate alcoholic liver injury and define new therapeutic targets. Lieber-DeCarli diet (LD) and Meadows-Cook diet (MC) are the most accepted models of chronic alcohol consumption. It is unclear how similar these models are at the cellular, immunologic, and transcriptome levels. We investigated the common and specific pathways of LD and MC models. Livers from LD and MC mice were subjected to histologic changes, hepatic leukocyte population, hepatic transcripts level related to leukocyte recruitment, and hepatic RNA-seq analysis. Cross-species comparison was performed using the alcoholic liver disease (ALD) transcriptomic public dataset. Despite LD mice have increased liver injury and steatosis by alcohol exposure, the number of CD45
+ cells were reduced. Opposite, MC mice have an increased number of monocytes/liver by alcohol. The pattern of chemokine gradient, adhesion molecules, and cytokine transcripts is highly specific for each model, not shared with advanced human alcoholic liver disease. Moreover, hepatic RNA-seq revealed a limited and restricted number of shared genes differentially changed by alcohol exposure in these 2 models. Thus, mechanisms involved in alcohol tissue injury are model-dependent at multiple levels and raise the consideration of significant pathophysiological diversity of human alcoholic liver injury.- Published
- 2020
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8. A New Picture of the Global Impacts of El Nino-Southern Oscillation.
- Author
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Lin J and Qian T
- Abstract
The El Nino-Southern Oscillation (ENSO) is the dominant interannual variability of Earth's climate system and plays a central role in global climate prediction. Outlooks of ENSO and its impacts often follow a two-tier approach: predicting ENSO sea surface temperature anomaly in tropical Pacific and then predicting its global impacts. However, the current picture of ENSO global impacts widely used by forecasting centers and atmospheric science textbooks came from two earliest surface station datasets complied 30 years ago, and focused on the extreme phases rather than the whole ENSO lifecycle. Here, we demonstrate a new picture of the global impacts of ENSO throughout its whole lifecycle based on the rich latest satellite, in situ and reanalysis datasets. ENSO impacts are much wider than previously thought. There are significant impacts unknown in the previous picture over Europe, Africa, Asia and North America. The so-called "neutral years" are not neutral, but are associated with strong sea surface temperature anomalies in global oceans outside the tropical Pacific, and significant anomalies of land surface air temperature and precipitation over all the continents.
- Published
- 2019
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9. Switch Between El Nino and La Nina is Caused by Subsurface Ocean Waves Likely Driven by Lunar Tidal Forcing.
- Author
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Lin J and Qian T
- Abstract
The El Nino-Southern Oscillation (ENSO) is the dominant interannual variability of Earth's climate system, and strongly modulates global temperature, precipitation, atmospheric circulation, tropical cyclones and other extreme events. However, forecasting ENSO is one of the most difficult problems in climate sciences affecting both interannual climate prediction and decadal prediction of near-term global climate change. The key question is what cause the switch between El Nino and La Nina. For the past 30 years, ENSO forecasts have been limited to short lead times after ENSO sea surface temperature (SST) anomaly has already developed, but unable to predict the switch between El Nino and La Nina. Here, we demonstrate that the switch between El Nino and La Nina is caused by a subsurface ocean wave propagating from western Pacific to central and eastern Pacific and then triggering development of SST anomaly. This is based on analysis of all ENSO events in the past 136 years using multiple long-term observational datasets. The wave's slow phase speed and decoupling from atmosphere indicate that it is a forced wave. Further analysis of Earth's angular momentum budget and NASA's Apollo Landing Mirror Experiment suggests that the subsurface wave is likely driven by lunar tidal gravitational force.
- Published
- 2019
- Full Text
- View/download PDF
10. Resting-state brain information flow predicts cognitive flexibility in humans.
- Author
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Chén OY, Cao H, Reinen JM, Qian T, Gou J, Phan H, De Vos M, and Cannon TD
- Subjects
- Adult, Connectome, Female, Humans, Magnetic Resonance Imaging, Male, Models, Neurological, Models, Psychological, Rest, Signal Processing, Computer-Assisted, Young Adult, Brain diagnostic imaging, Brain physiology, Cognition physiology
- Abstract
The human brain is a dynamic system, where communication between spatially distinct areas facilitates complex cognitive functions and behaviors. How information transfers between brain regions and how it gives rise to human cognition, however, are unclear. In this article, using resting-state functional magnetic resonance imaging (fMRI) data from 783 healthy adults in the Human Connectome Project (HCP) dataset, we map the brain's directed information flow architecture through a Granger-Geweke causality prism. We demonstrate that the information flow profiles in the general population primarily involve local exchanges within specialized functional systems, long-distance exchanges from the dorsal brain to the ventral brain, and top-down exchanges from the higher-order systems to the primary systems. Using an information flow map discovered from 550 subjects, the individual directed information flow profiles can significantly predict cognitive flexibility scores in 233 novel individuals. Our results provide evidence for directed information network architecture in the cerebral cortex, and suggest that features of the information flow configuration during rest underpin cognitive ability in humans.
- Published
- 2019
- Full Text
- View/download PDF
11. Directed Differentiation of Human Pluripotent Stem Cells to Podocytes under Defined Conditions.
- Author
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Qian T, Hernday SE, Bao X, Olson WR, Panzer SE, Shusta EV, and Palecek SP
- Subjects
- Cells, Cultured, Humans, Mesoderm cytology, Mesoderm metabolism, Nanog Homeobox Protein genetics, Nanog Homeobox Protein metabolism, Octamer Transcription Factor-3 genetics, Octamer Transcription Factor-3 metabolism, Phenotype, Pluripotent Stem Cells metabolism, Podocytes metabolism, Primitive Streak cytology, Primitive Streak metabolism, Wnt Proteins metabolism, Cell Differentiation, Pluripotent Stem Cells cytology, Podocytes cytology
- Abstract
A major cause of chronic kidney disease (CKD) is glomerular disease, which can be attributed to a spectrum of podocyte disorders. Podocytes are non-proliferative, terminally differentiated cells. Thus, the limited supply of primary podocytes impedes CKD research. Differentiation of human pluripotent stem cells (hPSCs) into podocytes has the potential to produce podocytes for disease modeling, drug screening, and cell therapies. In the podocyte differentiation process described here, hPSCs are first induced to primitive streak-like cells by activating canonical Wnt signaling. Next, these cells progress to mesoderm precursors, proliferative nephron progenitors, and eventually become mature podocytes by culturing in a serum-free medium. Podocytes generated via this protocol adopt podocyte morphology, express canonical podocyte markers, and exhibit podocyte phenotypes, including albumin uptake and TGF-β1 triggered cell death. This study provides a simple, defined strategy to generate podocytes for in vitro modeling of podocyte development and disease or for cell therapies.
- Published
- 2019
- Full Text
- View/download PDF
12. Electronic structure of SrSn 2 As 2 near the topological critical point.
- Author
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Rong LY, Ma JZ, Nie SM, Lin ZP, Li ZL, Fu BB, Kong LY, Zhang XZ, Huang YB, Weng HM, Qian T, Ding H, and Tai RZ
- Abstract
Topological materials with exotic quantum properties are promising candidates for quantum spin electronics. Different classes of topological materials, including Weyl semimetal, topological superconductor, topological insulator and Axion insulator, etc., can be connected to each other via quantum phase transition. For example, it is believed that a trivial band insulator can be twisted into topological phase by increasing spin-orbital coupling or changing the parameters of crystal lattice. With the results of LDA calculation and measurement by angle-resolved photoemission spectroscopy (ARPES), we demonstrate in this work that the electronic structure of SrSn
2 As2 single crystal has the texture of band inversion near the critical point. The results indicate the possibility of realizing topological quantum phase transition in SrSn2 As2 single crystal and obtaining different exotic quantum states.- Published
- 2017
- Full Text
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13. Enhanced thermal conductivity of form-stable phase change composite with single-walled carbon nanotubes for thermal energy storage.
- Author
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Qian T, Li J, Feng W, and Nian H
- Abstract
A striking contrast in the thermal conductivities of polyethylene glycol (PEG)/diatomite form-stable phase change composite (fs-PCC) with single-walled carbon nanotubes (SWCNs) as nano-additive has been reported in our present study. Compared to the pure PEG, the thermal conductivity of the prepared fs-PCC has increased from 0.24 W/mK to 0.87 W/Mk with a small SWCNs loading of 2 wt%. SWCNs are decorated on the inner surface of diatomite pores whilst retaining its porous structure. Compared to PEG/diatomite fs-PCC, the melting and solidification time of the PEG/diatomite/SWCNs fs-PCC are respectively decreased by 54.7% and 51.1%, and its thermal conductivity is 2.8 times higher. The composite can contain PEG as high as 60 wt% and maintain its original shape perfectly without any PEG leakage after subjected to 200 melt-freeze cycles. DSC results indicates that the melting point of the PEG/diatomite/SWCNs fs-PCC shifts to a lower temperature while the solidification point shifts to a higher temperature due to the presence of SWCNs. Importantly, the use of SWCNs is found to have clear beneficial effects for enhancing the thermal conductivity and thermal storage/release rates, without affecting thermal properties, chemical compatibility and thermal stability. The prepared PEG/diatomite/SWCNs fs-PCC exhibits excellent chemical and thermal durability and has potential application in solar thermal energy storage and solar heating.
- Published
- 2017
- Full Text
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14. Crystal Structure of StnA for the Biosynthesis of Antitumor Drug Streptonigrin Reveals a Unique Substrate Binding Mode.
- Author
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Qian T, Wo J, Zhang Y, Song Q, Feng G, Luo R, Lin S, Wu G, and Chen HF
- Subjects
- Antibiotics, Antineoplastic pharmacokinetics, Bacterial Proteins ultrastructure, Carboxylic Ester Hydrolases ultrastructure, Catalytic Domain, Escherichia coli, Molecular Conformation, Molecular Dynamics Simulation, Sequence Analysis, Protein, Streptonigrin chemistry, Substrate Specificity, Antibiotics, Antineoplastic chemistry, Bacterial Proteins chemistry, Carboxylic Ester Hydrolases chemistry, Streptonigrin biosynthesis
- Abstract
Streptonigrin methylesterase A (StnA) is one of the tailoring enzymes that modify the aminoquinone skeleton in the biosynthesis pathway of Streptomyces species. Although StnA has no significant sequence homology with the reported α/β-fold hydrolases, it shows typical hydrolytic activity in vivo and in vitro. In order to reveal its functional characteristics, the crystal structures of the selenomethionine substituted StnA (SeMet-StnA) and the complex (S185A mutant) with its substrate were resolved to the resolution of 2.71 Å and 2.90 Å, respectively. The overall structure of StnA can be described as an α-helix cap domain on top of a common α/β hydrolase domain. The substrate methyl ester of 10'-demethoxystreptonigrin binds in a hydrophobic pocket that mainly consists of cap domain residues and is close to the catalytic triad Ser185-His349-Asp308. The transition state is stabilized by an oxyanion hole formed by the backbone amides of Ala102 and Leu186. The substrate binding appears to be dominated by interactions with several specific hydrophobic contacts and hydrogen bonds in the cap domain. The molecular dynamics simulation and site-directed mutagenesis confirmed the important roles of the key interacting residues in the cap domain. Structural alignment and phylogenetic tree analysis indicate that StnA represents a new subfamily of lipolytic enzymes with the specific binding pocket located at the cap domain instead of the interface between the two domains.
- Published
- 2017
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15. A new insight into the immobilization mechanism of Zn on biochar: the role of anions dissolved from ash.
- Author
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Qian T, Wang Y, Fan T, Fang G, and Zhou D
- Abstract
Biochar is considered to be a promising material for heavy metal immobilization in soil. However, the immobilization mechanisms of Zn(2+) on biochars derived from many common waste biomasses are not completely understood. Herein, biochars (denoted as PN350, PN550, WS350, and WS550) derived from pine needle (PN) and wheat straw (WS) were prepared at two pyrolysis temperatures (350 °C and 550 °C). The immobilization behaviors and mechanisms of Zn(2+) on these biochars were systematically investigated. The results show that compared with biochars produced at low temperature, biochars produced at high temperature contained higher amounts of ash and exhibited much higher sorption capacities of Zn(2+). By using Zn K-edge EXAFS spectroscopy, we find that the formation of various Zn precipitates/minerals, which was caused by the release of OH(-), CO3(2-), and Si species from biochar, was the immobilization mechanism of Zn(2+) on PN and WS biochars. Hydrozincite and Zn(OH)2 were the main species formed on PN350, PN550, and WS350; while on WS550, besides hydrozincite, a large fraction of hemimorphite was formed. The occurrence of hydrozincite and hemimorphite on biochar during Zn(2+) immobilization is firstly reported in our study, which provides a new insight into the immobilization mechanism of Zn(2+) on biochar.
- Published
- 2016
- Full Text
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16. Pore structure modified diatomite-supported PEG composites for thermal energy storage.
- Author
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Qian T, Li J, and Deng Y
- Abstract
A series of novel composite phase change materials (PCMs) were tailored by blending PEG and five kinds of diatomite via a vacuum impregnation method. To enlarge its pore size and specific surface area, different modification approaches including calcination, acid treatment, alkali leaching and nano-silica decoration on the microstructure of diatomite were outlined. Among them, 8 min of 5 wt% NaOH dissolution at 70 °C has been proven to be the most effective and facile. While PEG melted during phase transformation, the maximum load of PEG could reach 70 wt.%, which was 46% higher than that of the raw diatomite. The apparent activation energy of PEG in the composite was 1031.85 kJ·mol(-1), which was twice higher than that of the pristine PEG. Moreover, using the nano-silica decorated diatomite as carrier, the maximum PEG load was 66 wt%. The composite PCM was stable in terms of thermal and chemical manners even after 200 cycles of melting and freezing. All results indicated that the obtained composite PCMs were promising candidate materials for building applications due to its large latent heat, suitable phase change temperature, excellent chemical compatibility, improved supercooling extent, high thermal stability and long-term reliability.
- Published
- 2016
- Full Text
- View/download PDF
17. Enhanced thermal properties of novel shape-stabilized PEG composite phase change materials with radial mesoporous silica sphere for thermal energy storage.
- Author
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Min X, Fang M, Huang Z, Liu Y, Huang Y, Wen R, Qian T, and Wu X
- Abstract
Radial mesoporous silica (RMS) sphere was tailor-made for further applications in producing shape-stabilized composite phase change materials (ss-CPCMs) through a facile self-assembly process using CTAB as the main template and TEOS as SiO2 precursor. Novel ss-CPCMs composed of polyethylene glycol (PEG) and RMS were prepared through vacuum impregnating method. Various techniques were employed to characterize the structural and thermal properties of the ss-CPCMs. The DSC results indicated that the PEG/RMS ss-CPCM was a promising candidate for building thermal energy storage applications due to its large latent heat, suitable phase change temperature, good thermal reliability, as well as the excellent chemical compatibility and thermal stability. Importantly, the possible formation mechanisms of both RMS sphere and PEG/RMS composite have also been proposed. The results also indicated that the properties of the PEG/RMS ss-CPCMs are influenced by the adsorption limitation of the PEG molecule from RMS sphere with mesoporous structure and the effect of RMS, as the impurities, on the perfect crystallization of PEG.
- Published
- 2015
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18. Subcellular and Dynamic Coordination between Src Activity and Cell Protrusion in Microenvironment.
- Author
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Zhuo Y, Qian T, Wu Y, Seong J, Gong Y, Ma H, Wang Y, and Lu S
- Subjects
- Cell Movement genetics, Cell Polarity genetics, Cell Surface Extensions genetics, Endothelial Cells metabolism, Fluorescence Resonance Energy Transfer, Humans, Neovascularization, Physiologic genetics, src-Family Kinases genetics, Cellular Microenvironment genetics, Endothelial Cells cytology, Wound Healing genetics, src-Family Kinases metabolism
- Abstract
Migration of endothelial cells is essential for wound healing and angiogenesis. Src kinase activity plays important roles at the protrusions of migrating endothelial cells. However, the spatiotemporal coordination between Src kinase activity and the protrusion of cell edge remains unclear. Therefore, we investigate these coordinated molecular events at the initiation of cell migration, by integrating microfabrication, fluorescence resonance energy transfer (FRET)-based biosensors, and automated computational image analysis. We demonstrate that the physical release of restrictive micropattern triggered a significant decrease of Src activity at the protrusive edge of endothelial cells. Computational cross-correlation analysis reveals that the decrease of Src activity occurred earlier in time, and was well-coordinated with the protrusion of cell edge in polarized cells, but not in non-polarized cells. These results suggest that the spatiotemporal control of Src kinase activity is well-coordinated with cell polarization and protrusion in endothelial cells upon the release of physical constraint, as that experienced by endothelial cells sprouting from stiff tumor micro-environment during angiogenesis. Therefore, our integrative approach enabled the discovery of a new model where Src is de-activated in coordination with membrane protrusion, providing important insights into the regulation of endothelial migration and angiogenesis.
- Published
- 2015
- Full Text
- View/download PDF
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