171 results on '"Yuandong Li"'
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2. Deep Imaging to Dissect Microvascular Contributions to White Matter Degeneration in Rodent Models of Dementia
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Stefan Stamenkovic, Yuandong Li, Jack Waters, and Andy Shih
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Advanced and Specialized Nursing ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine - Abstract
The increasing socio-economic burden of Alzheimer disease (AD) and AD-related dementias has created a pressing need to define targets for therapeutic intervention. Deficits in cerebral blood flow and neurovascular function have emerged as early contributors to disease progression. However, the cause, progression, and consequence of small vessel disease in AD/AD-related dementias remains poorly understood, making therapeutic targets difficult to pinpoint. Animal models that recapitulate features of AD/AD-related dementias may provide mechanistic insight because microvascular pathology can be studied as it develops in vivo. Recent advances in in vivo optical and ultrasound-based imaging of the rodent brain facilitate this goal by providing access to deeper brain structures, including white matter and hippocampus, which are more vulnerable to injury during cerebrovascular disease. Here, we highlight these novel imaging approaches and discuss their potential for improving our understanding of vascular contributions to AD/AD-related dementias.
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- 2023
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3. Microstructure and yield phenomenon of an extruded Mg-Y-Cu alloy with LPSO phase
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Guangli Bi, Niuming Zhang, Jing Jiang, Yuandong Li, Tijun Chen, Wei Fu, Xiaoru Zhang, Daqing Fang, and Xiangdong Ding
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Geochemistry and Petrology ,General Chemistry - Published
- 2023
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4. Improvement in the age-hardening response of Mg–7Sn alloy by compressive stress-assisted aging
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Jing Jiang, Lin Tong, Zuocheng Xu, Guangli Bi, Chi Cao, Yuandong Li, Tijun Chen, Wei Fu, and Daqing Fang
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Biomaterials ,Metals and Alloys ,Ceramics and Composites ,Surfaces, Coatings and Films - Published
- 2023
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5. Versatile, facile and low-cost single-cell isolation, culture and sequencing by optical tweezer-assisted pool-screening
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Teng Xu, Yuandong Li, Xiao Han, Lingyan Kan, Jing Ren, Luyang Sun, Zhidian Diao, Yuetong Ji, Pengfei Zhu, Jian Xu, and Bo Ma
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Biomedical Engineering ,Bioengineering ,General Chemistry ,Biochemistry - Abstract
Real-time image-based sorting of target cells in a precisely indexed manner is desirable for sequencing or cultivating individual human or microbial cells directly from clinical or environmental samples; however, the versatility of existing methods is limited as they are usually not broadly applicable to all cell sizes. Here, an optical tweezer-assisted pool-screening and single-cell isolation (OPSI) system is established for precise, indexed isolation of individual bacterial, yeast or human-cancer cells. A controllable static flow field that acts as a cell pool is achieved in a microfluidics chip, to enable precise and ready screening of cells of 1 to 40 μm in size by bright-field, fluorescence, or Raman imaging. The target cell is then captured by a 1064 nm optical tweezer and deposited as one-cell-harboring nanoliter microdroplets in a one-cell-one-tube manner. For bacterial, yeast and human cells, OPSI achieves a99.7% target-cell sorting purity and a 10-fold elevated speed of 10-20 cells per min. Moreover, OPSI-based one-cell RNA-seq of human cancer cells yields high quality and reproducible single-cell transcriptome profiles. The versatility, facileness, flexibility, modularized design, and low cost of OPSI suggest its broad applications for image-based sorting of target cells.
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- 2023
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6. Artificial intelligence‐assisted automatic and index‐based microbial single‐cell sorting system for One‐Cell‐One‐Tube
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Zhidian Diao, Lingyan Kan, Yilong Zhao, Huaibo Yang, Jingyun Song, Chen Wang, Yang Liu, Fengli Zhang, Teng Xu, Rongze Chen, Yuetong Ji, Xixian Wang, Xiaoyan Jing, Jian Xu, Yuandong Li, and Bo Ma
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- 2022
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7. Effects of Zn addition on microstructure and tensile properties of Mg–Y–Co alloy
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Guangli Bi, Hongsheng Man, Jing Jiang, Yuandong Li, Tijun Chen, Xiaoru Zhang, Daqing Fang, and Xiangdong Ding
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Biomaterials ,Metals and Alloys ,Ceramics and Composites ,Surfaces, Coatings and Films - Published
- 2022
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8. Neural network-based fault diagnosis for spacecraft with single-gimbal control moment gyros
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Xiaodong Shao, Yuandong Li, and Qinglei Hu
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Moment (mathematics) ,Spacecraft ,Artificial neural network ,business.industry ,Control theory ,Computer science ,Mechanical Engineering ,Adaptive estimator ,Aerospace Engineering ,Gimbal ,Fault (power engineering) ,business ,Fault detection and isolation - Abstract
This paper proposes a neural network-based fault diagnosis scheme to address the problem of fault isolation and estimation for the Single-Gimbal Control Moment Gyroscopes (SGCMGs) of spacecraft in a periodic orbit. To this end, a disturbance observer based on neural network is developed for active anti-disturbance, so as to improve the accuracy of fault diagnosis. The periodic disturbance on orbit can be decoupled with fault by resorting to the fitting and memory ability of neural network. Subsequently, the fault diagnosis scheme is established based on the idea of information fusion. The data of spacecraft attitude and gimbals position are combined to implement fault isolation and estimation based on adaptive estimator and neural network. Then, an adaptive sliding mode controller incorporating the disturbance and fault estimation results is designed to achieve active fault-tolerant control. In addition, the paper gives the proof of the stability of the proposed schemes, and the simulation results show that the proposed scheme achieves better diagnosis and control results than compared algorithm.
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- 2022
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9. Effects of Laser Surface Remelting on Microstructure and Corrosion Properties of Mg-12Dy-1.1Ni Alloy
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Guangli Bi, Siqi Chen, Jing Jiang, Yuandong Li, Tijun Chen, Xiao-Bo Chen, Duyao Zhang, Dong Qiu, and Mark Easton
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Abstract
Effects of laser surface remelting (LSR) on microstructure and corrosion properties of as-cast Mg-12Dy-1.1Ni (wt.%) alloy were investigated. The as-cast alloy was mainly composed of α-Mg, lamellar Mg12DyNi phase with an 18R-long period stacking order (LPSO) structure and Mg24Dy5. After LSR treatment, fine and compact 18R-LPSO phase reprecipitated on dendrite boundaries as a continuous network. In addition, the volume fraction of the LPSO phase remarkably increased to 34.9% and the grain size of as-cast alloy was refined to ca. 4 μm. Electrochemical and immersion tests indicated that the LSR-treated alloy exhibited a lower weight loss rate (2.8 ± 0.2 mg/cm2/h) and corrosion current density (160.1 ± 20.7 μA/cm2, and of 37% reduction after LSR) than the as-cast alloy in 0.1 M NaCl solution. The improved corrosion resistance of the LSR alloy was mainly ascribed to the grain refinement and continuous distribution of 18R-LPSO phase on dendrite boundaries.
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- 2022
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10. Rapid, automated, and reliable antimicrobial susceptibility test from positive blood culture by CAST‐R
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Pengfei Zhu, Lihui Ren, Ying Zhu, Jing Dai, Huijie Liu, Yuli Mao, Yuandong Li, Yuehui He, Xiaoshan Zheng, Rongze Chen, Xiaoting Fu, Lili Zhang, Lijun Sun, Yuanqi Zhu, Yuetong Ji, Bo Ma, Yingchun Xu, Jian Xu, and Qiwen Yang
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- 2022
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11. A Rapidly Degradable Extruded Mg–Y–Zn–Ni Alloy for Fracturing Tool Applications
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Guangli Bi, Maocao Le, Jing Jiang, Baiyu Li, Yuandong Li, Tijun Chen, and Ying Ma
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General Materials Science ,Condensed Matter Physics - Published
- 2023
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12. Fluidized Bed Heat Treating of a Magnesium-Rare Earth Alloy
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Jayme Keist, Yuandong Li, and Diran Apelian
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Mechanics of Materials ,Materials Chemistry ,Metals and Alloys ,Industrial and Manufacturing Engineering - Published
- 2022
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13. Single-cell Raman-activated sorting and cultivation (scRACS-Culture) for assessing and mining in situ phosphate-solubilizing microbes from nature
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Xiaoyan Jing, Yanhai Gong, Huihui Pan, Yu Meng, Yishang Ren, Zhidian Diao, Runzhi Mu, Teng Xu, Jia Zhang, Yuetong Ji, Yuandong Li, Chen Wang, Lingyun Qu, Li Cui, Bo Ma, and Jian Xu
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General Medicine - Abstract
Due to the challenges in detecting in situ activity and cultivating the not-yet-cultured, functional assessment and mining of living microbes from nature has typically followed a ‘culture-first’ paradigm. Here, employing phosphate-solubilizing microbes (PSM) as model, we introduce a ‘screen-first’ strategy that is underpinned by a precisely one-cell-resolution, complete workflow of single-cell Raman-activated Sorting and Cultivation (scRACS-Culture). Directly from domestic sewage, individual cells were screened for in-situ organic-phosphate-solubilizing activity via D2O intake rate, sorted by the function via Raman-activated Gravity-driven Encapsulation (RAGE), and then cultivated from precisely one cell. By scRACS-Culture, pure cultures of strong organic PSM including Comamonas spp., Acinetobacter spp., Enterobacter spp. and Citrobacter spp., were derived, whose phosphate-solubilizing activities in situ are 90–200% higher than in pure culture, underscoring the importance of ‘screen-first’ strategy. Moreover, employing scRACS-Seq for post-RACS cells that remain uncultured, we discovered a previously unknown, low-abundance, strong organic-PSM of Cutibacterium spp. that employs secretary metallophosphoesterase (MPP), cell-wall-anchored 5′-nucleotidase (encoded by ushA) and periplasmic-membrane located PstSCAB-PhoU transporter system for efficient solubilization and scavenging of extracellular phosphate in sewage. Therefore, scRACS-Culture and scRACS-Seq provide an in situ function-based, ‘screen-first’ approach for assessing and mining microbes directly from the environment.
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- 2022
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14. GPR39 Knockout Worsens Microcirculatory Response to Experimental Stroke in a Sex-Dependent Manner
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Yifan Xu, Wenri H. Zhang, Elyse M. Allen, Lev M. Fedorov, Anthony P. Barnes, Zu Yuan Qian, Thierno Madjou Bah, Yuandong Li, Ruikang K. Wang, Robert E. Shangraw, and Nabil J. Alkayed
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General Neuroscience ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine - Published
- 2022
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15. Adaptive Response and Transcriptomic Analysis of Flax (
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Yuandong, Li, Jiao, Chen, Xiao, Li, Haixia, Jiang, Dongliang, Guo, Fang, Xie, Zeyang, Zhang, and Liqiong, Xie
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Plant Breeding ,Soil ,Proline ,Seedlings ,Flax ,Gene Expression Profiling ,Sodium Chloride ,Reactive Oxygen Species ,Transcriptome ,Sugars ,Salt Stress ,Antioxidants - Abstract
Soil salinity constrains agricultural development in arid regions. Flax is an economically important crop in many countries, and screening or breeding salinity-resistant flax cultivars is necessary. Based on the previous screening of flaxseed cultivars C71 (salt-sensitive) and C116 (salt-tolerant) as test materials, flax seedlings stressed with different concentrations of NaCl (0, 100, 150, 200, and 250 mmol/L) for 21 days were used to investigate the effects of salt stress on the growth characteristics, osmotic regulators, and antioxidant capacity of these flax seedlings and to reveal the adaptive responses of flax seedlings to salt stress. The results showed that plant height and root length of flax were inhibited, with C116 showing lower growth than C71. The concentrations of osmotic adjustment substances such as soluble sugars, soluble proteins, and proline were higher in the resistant material, C116, than in the sensitive material, C71, under different concentrations of salt stress. Consistently, C116 showed a better rapid scavenging ability for reactive oxygen species (ROS) and maintained higher activities of antioxidant enzymes to balance salt injury stress by inhibiting growth under salt stress. A transcriptome analysis of flax revealed that genes related to defense and senescence were significantly upregulated, and genes related to the growth and development processes were significantly downregulated under salt stress. Our results indicated that one of the important adaptations to tolerance to high salt stress is complex physiological remediation by rapidly promoting transcriptional regulation in flax.
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- 2022
16. Discussion on the Theoretical Basis for Cross-Over Method Applied to Downhole Wave Velocity Test
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Qing Dong, Bing Hao, Yuandong Li, Su Jie, and Zhenghua Zhou
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Article Subject ,010504 meteorology & atmospheric sciences ,Computer simulation ,Polarity (physics) ,Physics ,QC1-999 ,Mechanical Engineering ,Geophone ,Mechanics ,Impulse (physics) ,010502 geochemistry & geophysics ,Geotechnical Engineering and Engineering Geology ,Condensed Matter Physics ,01 natural sciences ,Finite element method ,Background noise ,Mechanics of Materials ,Deflection (engineering) ,Longitudinal wave ,Geology ,0105 earth and related environmental sciences ,Civil and Structural Engineering - Abstract
At engineering practice, the theoretical basis for the cross-over method, used to obtain shear wave arrival time in the downhole method of the wave velocity test by surface forward and backward strike, is that the polarity of P-wave keeps the same, while the polarity of S-wave transforms when the direction of strike inverted. However, the characteristics of signals recorded in tests are often found to conflict with this theoretical basis for the cross-over method, namely, the polarity of the P-wave also transforms under the action of surface forward and backward strike. Therefore, 3D finite element numerical simulations were conducted to study the validity of the theoretical basis for the cross-over method. The results show that both shear and compression waves are observed to be in 180° phase difference between horizontal signal traces, consistent with the direction of excitation generated by reversed impulse. Furthermore, numerical simulation results prove to be reliable by the analytic solution; it shows that the theoretical basis for the cross-over method applied to the downhole wave velocity test is improper. In meanwhile, numerical simulations reveal the factors (inclining excitation, geophone deflection, inclination, and background noise) that may cause the polarity of the P-wave not to reverse under surface forward and backward strike. Then, as to reduce the influence factors, we propose a method for the downhole wave velocity test under surface strike, the time difference of arrival is based between source peak and response peak, and numerical simulation results show that the S-wave velocity by this method is close to the theoretical S-wave velocity of soil.
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- 2021
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17. Label-free droplet-based bacterial growth phenotype screening by a mini integrated microfluidic platform
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Anle Ge, Zhidian Diao, Fengyi Liu, Yuandong Li, Chaojie Cui, Shoujie Li, Yang Liu, Jian Xu, and Bo Ma
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Materials Chemistry ,Metals and Alloys ,Electrical and Electronic Engineering ,Condensed Matter Physics ,Instrumentation ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Published
- 2023
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18. GPR39 Knockout Worsens Microcirculatory Response to Experimental Stroke in a Sex- Dependent Manner
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Yifan Xu, Wenri Zhang, Elyse Allen, Lev Fedorov, Anthony Barnes, Zu Yuan Qian, Thierno Bah, Yuandong Li, Ruikang Wang, Robert Shangraw, and Nabil Alkayed
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Background and Purpose No current treatments target microvascular reperfusion after stroke, which can contribute to poor outcomes even after successful clot retrieval. The G protein-coupled receptor GPR39 is expressed in brain peri-capillary pericytes, and has been implicated in microvascular regulation, but its role in stroke is unknown. We tested the hypothesis that GPR39 plays a protective role after stroke, in part due to preservation of microvascular perfusion. We generated GPR39 knockout (KO) mice and tested whether GPR39 gene deletion worsens capillary blood flow and exacerbates brain injury and functional deficit after focal cerebral ischemia. Methods Stroke was induced in male and female GPR39 KO and WT littermates by 60-minute middle cerebral artery occlusion (MCAO). Microvascular perfusion was assessed via capillary red blood cell (RBC) flux in deep cortical layers in vivo using optical microangiography (OMAG). Brain injury was assessed by measuring infarct size by 2,3,5-triphenyltetrazolium chloride staining at 24 hours or brain atrophy at 3 weeks after ischemia. Pole and cylinder behavior tests were conducted to assess neurological function deficit at 1 and 3 weeks post-stroke. Results Male but not female GPR39 KO mice exhibited larger infarcts and lower capillary RBC flux than WT controls after stroke. Male GPR39 KO mice also exhibited worse neurologic deficit at 1 week post-stroke, though functional deficit disappeared in both groups by 3 weeks. Conclusions GPR39 deletion worsens brain injury, microvascular perfusion, and neurological function after experimental stroke. Results indicate that GPR39 plays a sex-dependent role in re-establishing microvascular flow and limiting ischemic brain damage after stroke.
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- 2022
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19. GPR39 Knockout Worsens Microcirculatory Response to Experimental Stroke in a Sex-Dependent Manner
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Yifan, Xu, Wenri H, Zhang, Elyse M, Allen, Lev M, Fedorov, Anthony P, Barnes, Zu Yuan, Qian, Thierno Madjou, Bah, Yuandong, Li, Ruikang K, Wang, Robert E, Shangraw, and Nabil J, Alkayed
- Abstract
No current treatments target microvascular reperfusion after stroke, which can contribute to poor outcomes even after successful clot retrieval. The G protein-coupled receptor GPR39 is expressed in brain peri-capillary pericytes, and has been implicated in microvascular regulation, but its role in stroke is unknown. We tested the hypothesis that GPR39 plays a protective role after stroke, in part due to preservation of microvascular perfusion. We generated GPR39 knockout (KO) mice and tested whether GPR39 gene deletion worsens capillary blood flow and exacerbates brain injury and functional deficit after focal cerebral ischemia. Stroke was induced in male and female GPR39 KO and WT littermates by 60-min middle cerebral artery occlusion (MCAO). Microvascular perfusion was assessed via capillary red blood cell (RBC) flux in deep cortical layers in vivo using optical microangiography (OMAG). Brain injury was assessed by measuring infarct size by 2,3,5-triphenyltetrazolium chloride staining at 24 h or brain atrophy at 3 weeks after ischemia. Pole and cylinder behavior tests were conducted to assess neurological function deficit at 1 and 3 weeks post-stroke. Male but not female GPR39 KO mice exhibited larger infarcts and lower capillary RBC flux than WT controls after stroke. Male GPR39 KO mice also exhibited worse neurologic deficit at 1 week post-stroke, though functional deficit disappeared in both groups by 3 weeks. GPR39 deletion worsens brain injury, microvascular perfusion, and neurological function after experimental stroke. Results indicate that GPR39 plays a sex-dependent role in re-establishing microvascular flow and limiting ischemic brain damage after stroke.
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- 2022
20. Analysis of the Mechanism of Ground Fissures in the Nairobi–Malaba Railway Rift Valley Area in Kenya
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Bing Hao, Zhenghua Zhou, Yuandong Li, Xiaojun Li, Xujin Liu, Yi Han, and Liguo Jin
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General Earth and Planetary Sciences - Abstract
During the rainy season from March to May 2018, four ground fissures were generated in the rift valley area along the first phase of the Nairobi–Malaba Railway in Kenya, among which the ground fissures B3 highway, DK76, and DK77 were larger in scale, which seriously endangered the safety of the railway. According to the author’s previous study, the ground fissure B3 highway belongs to a typical fault-type fissure, and the ground fissures DK76 and DK77 are qualitatively concluded to be generated under the groundwater erosion of collapsible soils. To quantitatively summarize the mechanism of ground fissures, DK76 and DK77, physical model tests on the overlying soil properties, compactness, the intersection angle between hidden cracks and the water flow direction, the height of confined water level, and the groundwater flow rate are conducted to analyze the effect of these factors on the formation and expansion of ground fissures. The test results show that the soil with strong collapsibility under the action of underground erosion produces fissures, collapses, and holes similar to those in the rift valley area along the first phase of the Nairobi–Malaba Railway in Kenya; the loose overburden is conducive to the occurrence of surface collapse; the collapse of the soil surface is the most severe when the underlaid cracks are parallel to the water flow direction; the higher confined water level and faster inflow rate will aggravate the collapse of the overlying soil layer.
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- 2022
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21. Study on the γ + X, γ + β, γ + α Coincidence Summing Effects of the Intrinsic Background Instrument Spectrum of a LaBr3(Ce) Scintillation Counter
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Yuandong Li, Liangquan Ge, Shangqing Sun, and Chuanhao Hu
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010302 applied physics ,Physics ,Resolution (electron density) ,Spectrum (functional analysis) ,Analytical chemistry ,General Physics and Astronomy ,02 engineering and technology ,Radiation measuring device ,021001 nanoscience & nanotechnology ,Software package ,01 natural sciences ,Coincidence ,Spectral line ,Crystal ,0103 physical sciences ,Scintillation counter ,0210 nano-technology - Abstract
The energy resolution of a LaBr3(Ce) scintillation counter can reach 2.7% (662 keV) at room temperature. As a radiation measuring device, it has remarkably good characteristics. However, the LaBr3(Ce) crystal has its own intrinsic radioactivity background, which mainly comes from 138La and from 227Ac and its daughters. 138La can emit β, γ and X-rays through β and γ decay; 227Ac and its daughters can emit α, β and γ-rays through a, β and γ decay. α, β and X-ray energy are characteristic while β-ray energy is continuous. The energy of α, β and X-rays is mainly deposited in the crystal unless the α, β and X-rays at the edge of the crystal can escape from the crystal. Therefore, the α, β, γ and X-rays generated by the intrinsic radioactivity of the crystal are superimposed on the instrument spectrum, which makes the instrument spectrum more complicated and produces the coincidence summing effects of γ + X, γ + β and γ + α.In this research, the GEANT4.9.5 software package was used to simulate the spectra of α, β, γ and X-rays. On the basis of a combination of fitting decomposition and reconstruction, the simulation spectrum of the LaBr3(Ce) self-radioactive background was obtained accurately and was verified by using physical experiments.
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- 2020
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22. High-Speed Impact Behavior and Microstructure Evolution of an Extruded Mg-7Sn-5Zn-3Al Alloy
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Xu Zuocheng, Fu Wei, Daqing Fang, J. L. Jiang, Tijun Chen, Guangli Bi, Xiangdong Ding, and Yuandong Li
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010302 applied physics ,Materials science ,Mechanical Engineering ,Alloy ,02 engineering and technology ,Split-Hopkinson pressure bar ,engineering.material ,Strain rate ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Grain size ,Mechanics of Materials ,0103 physical sciences ,engineering ,Dynamic recrystallization ,General Materials Science ,Texture (crystalline) ,Composite material ,Elongation ,0210 nano-technology - Abstract
In this study, the high-speed impact behavior and microstructure evolution of an extruded Mg-7Sn-5Zn-3Al alloy were investigated under different strain rates (1626-4126 s−1) using a Split Hopkinson pressure bar. The experimental results indicated that the number of twins and dynamic recrystallization (DRX) increased, while the average grain size of the extruded alloy continuously decreased with the increase in the strain rates. In addition, the texture type of the extruded alloy transformed from (0001) to (11-20) during impacts. The high-speed impact behavior of the extruded alloy was found to strongly depend on the strain rate at room temperature. The strain rate sensitivity (SRS) changed from positive to negative with the increase in the strain rate. The negative SRS was mainly attributed to the DRX and the formation of micro-cracks at high strain rates (3712 s−1< $$\dot{\varepsilon }$$
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- 2020
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23. The impact of native leptomeningeal collateralization on rapid blood flow recruitment following ischemic stroke
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Atsushi Kanoke, Eric To, Teiji Tominaga, Yuandong Li, Jialing Liu, Ruikang K. Wang, Yosuke Akamatsu, Yasuo Nishijima, and Chih C Lee
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Doppler OCT ,medicine.medical_specialty ,Computed Tomography Angiography ,Ultrasonography, Doppler, Transcranial ,Collateral Circulation ,030204 cardiovascular system & hematology ,Independent predictor ,Brain Ischemia ,Mice ,03 medical and health sciences ,Meninges ,0302 clinical medicine ,Internal medicine ,Stroke outcome ,Animals ,Medicine ,Mice, Inbred BALB C ,medicine.diagnostic_test ,business.industry ,Brain ,Genetic Variation ,Infarction, Middle Cerebral Artery ,Original Articles ,Blood flow ,Mice, Inbred C57BL ,Stroke ,Disease Models, Animal ,Neurology ,Cerebrovascular Circulation ,Angiography ,Ischemic stroke ,Cardiology ,Disease Susceptibility ,Neurology (clinical) ,Cardiology and Cardiovascular Medicine ,business ,Collateralization ,Blood Flow Velocity ,Tomography, Optical Coherence ,030217 neurology & neurosurgery - Abstract
The leptomeningeal collateral status is an independent predictor of stroke outcome. By means of optical coherent tomography angiography to compare two mouse strains with different extent of native leptomeningeal collateralization, we determined the spatiotemporal dynamics of collateral flow and downstream hemodynamics following ischemic stroke. A robust recruitment of leptomeningeal collateral flow was detected immediately after middle cerebral artery (MCA) occlusion in C57BL/6 mice, with continued expansion over the course of seven days. In contrast, little collateral recruitment was seen in Balb/C mice during- and one day after MCAO, which coincided with a greater infarct size and worse functional outcome compared to C57BL/6, despite a slight improvement of cortical perfusion seven days after MCAO. Both strains of mice experienced a reduction of blood flow in the penetrating arterioles (PA) by more than 90% 30-min after dMCAO, although the decrease of PA flow was greater and the recovery was less in the Balb/C mice. Further, Balb/C mice also displayed a prolonged greater heterogeneity of capillary transit time after dMCAO in the MCA territory compared to C57BL/6 mice. Our data suggest that the extent of native leptomeningeal collaterals affects downstream hemodynamics with a long lasting impact in the microvascular bed after cortical stroke.
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- 2020
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24. Study on the Energy Spectrum Response of a CdZnTe Detector
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Liangquan Ge, Chengjun Tan, Yuandong Li, Guoqiang Zeng, Shangqing Sun, and Kun Sun
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010302 applied physics ,Materials science ,Resolution (mass spectrometry) ,Physics::Instrumentation and Detectors ,business.industry ,Detector ,General Physics and Astronomy ,02 engineering and technology ,021001 nanoscience & nanotechnology ,01 natural sciences ,Diffusion capacitance ,Signal ,Noise (electronics) ,law.invention ,Capacitor ,Optics ,law ,Rise time ,0103 physical sciences ,High Energy Physics::Experiment ,0210 nano-technology ,business ,Energy (signal processing) - Abstract
In order to study the energy spectrum response of a CdZnTe detector, we firstly measured the temperature dependence and the bias dependence of the main characteristic parameters for both a quasi-hemispherical detector and a CAPture™ plus detector. Secondly, we designed a low-noise readout circuit for the CdZnTe detector and measured the noise. Finally, we evaluated the energy spectrum response of the detector to different radioactive sources at different temperatures by connecting the detector to the readout circuit. The research showed that both detectors had low leakage current and junction capacitance, as well as good stability in temperature and bias; the quasi-hemispheric detector had a smaller leakage current and junction capacitance compared to the CAPture™ plus detector; under zero input capacitor, the noise of the readout circuit was 612e, with the noise slope being 5.44e/pF; at room temperature(20 °C), the energy resolutions of the detector reached 3.84% and 1.36% for X-rays from 241Am (59.5 keV) and gamma-rays from 137Cs (662 keV), respectively; the signal-noise ratio of the output signal reached 31:1 with the rise time being 90 ns; at low temperature, the energy resolution reached 3.41% for the X-rays from 241Am (59.5 keV); the detector achieved an excellent spectrum response and was able to distinguish clearly the energy peaks of 152Eu and 226Ra.
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- 2020
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25. A 3-8bit Reconfigurable Hybrid ADC Architecture with Successive-approximation and Single-slope Stages for Computing in Memory
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Wuyu Fan, Yuandong Li, Li Du, Likai Li, and Yuan Du
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- 2022
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26. Automated counting of cerebral penetrating vessels using optical coherence tomography images of a mouse brain in vivo
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Woo June Choi, Yuandong Li, Ruikang K. Wang, and Jun Ki Kim
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Stroke ,Disease Models, Animal ,Mice ,Animals ,Brain ,Retinal Vessels ,General Medicine ,Tomography, Optical Coherence ,Capillaries - Abstract
Penetrating blood vessels emanating from cortical surface vasculature and lying deep in the cortex are essential vascular conduits for the shuttling of blood from superficial pial vessels to the capillary beds in parenchyma for the nourishment of neuronal brain tissues. Locating and counting the penetrating vessels is beneficial for the quantification of a course of ischemia in blood occlusive events such as stroke. This paper seeks to demonstrate and validate a method for automated penetrating vessel counting that uses optical coherence tomography (OCT).This paper proposes an OCT method that effectively identifies and grades the cortical penetrating vessels in perfusion. The key to the proposed method is the harnessing of vascular features found in the penetrating vessels, which are distinctive from those of other vessels. In particular, with an increase in the light attenuation and flow turbulence, the contrast in the mean projection of the OCT datacube decreases, whereas that in the maximum projection of the Doppler frequency variance datacube increases. By multiplying the inversion of the former with the latter, its binary thresholding is sufficient to highlight the penetrating vessels and allows for their counting over the projection image.A computational method that leverages the decrease in mean OCT projection intensity and the increase in Doppler frequency variance at the penetrating vessel is developed. It successfully identifies and counts penetrating vessels with a high accuracy of over 87%. The penetrating vessel density is observed to be significantly reduced in the mouse model of focal ischemic stroke.The OCT analysis is effective for counting penetrating blood vessels in mice brains and may be applied to the rapid diagnosis and treatment of stroke in stroke models of small animals.
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- 2022
27. circCOL12A1 induce epithelial–mesenchymal transition and facilitates oncogenesis in gastric cancer via miR-30b-3p/ZEB1 axis
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Xiaochong Zhang, Li Wang, Xiaoling Zhao, Xiaopeng Tian, Qiuxiang Lei, Yuandong Li, Limin Hui, Liangfang Tian, Shurui Xie, and Dengxiang Liu
- Abstract
Circular RNAs (circRNAs) play an essential regulatory role in gene expression. Abnormally expressed circRNAs contribute to the occurrence and development of multiple cancers including gastric cancer (GC). However, studies regarding circRNAs in GC remain inadequate. In this study, we used high-throughput screening assays and discovered that circCOL12A1 was significantly increased in GC tissues compared with that in normal gastric tissues. Overexpression of circCOL12A1 enhanced cell proliferation, whereas depletion of circCOL12A1 reduced GC cell migration and epithelial–mesenchymal transition (EMT) by regulating EMT-related gene expression. Mechanistically, circCOL12A1 sponged miR-30b-3p and inhibited miR-30b-3p activity and increased the expression of the EMT-related transcriptional factor, ZEB1. miR-30b-3p expression was lower in GC tissue and correlated with poor survival of GC patients. By contrast, ZEB1 was highly expressed in GC and played a role in promoting GC cell migration and EMT. Furthermore, we confirmed that upregulation of ZEB1 via circCOL12A1-induced inhibition of miR-30b-3p resulted in GC cell proliferation and migration by regulating the EMT process. We demonstrated a pivotal role of circCOL12A1 in regulating proliferation and migration in cancer cells, and the results suggest a therapeutic benefit from targeting the circCOL12A1/miR-30b-3p/ZEB1 pathway in GC.
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- 2022
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28. Genetic Diversity and Population Differentiation of Naked Carp (Gymnocypris przewalskii) Revealed by Cytochrome Oxidase Subunit I and D-Loop
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Di-an Fang, Hui Luo, Miao He, Chengcheng Mao, Zhen Kuang, Hongfang Qi, Dongpo Xu, Longfei Tan, and Yuandong Li
- Subjects
Ecology ,Ecology, Evolution, Behavior and Systematics - Abstract
The genetic diversity in the naked carp (Gymnocypris przewalskii) of China is threatened by climate change, human activities, as well as natural factors, eliciting conservation concerns. To explore the genetic aspects of G. przewalskii, the genetic diversity, genetic structure, population differentiation, and historical demography of 566 representative individuals from seven geographically distinct ranges of Qinghai Lake were evaluated by mitochondrial DNA cytochrome oxidase subunit I (COI) and D-loop sequences. Estimates of genetic parameters showed that the seven populations of G. przewalskii had high levels of haplotype diversity (0.50243–0.94620) and low levels of nucleotide diversity (0.00079–0.00624). Haplotype genealogy indicated there was no obvious phylogenetic pattern between haplotypes. Both markers denoted the absence of population genetic structure [the genetic differentiation coefficient F-statistics (Fst) < 0] and the presence of high genetic flow (COI: 0.9731–1.0441; D-loop: 0.9480–1.0398). The mismatch between the distribution and neutrality tests supported the evidence of population expansion, which occurred during the late middle Pleistocene [COI: 0.36–0.108 MYA (Million Years Ago); D-loop: 0.497–0.165 MYA]. Furthermore, this work illustrated two simple, reliable, and inexpensive molecular markers for analysis of genetic diversity, while the sensitivity of the mitochondrial D-loop region as a reflection of genetic diversity in G. przewalskii is higher than that of the COI gene.
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- 2022
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29. Single input polarization sensitive optical coherence tomography for imaging depth-resolved collagen organizations
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Peijun Tang, Ruikang K. Wang, Mitchell A. Kirby, Nhan Le, Yuandong Li, Nicole Zeinstra, G. Nina Lu, Charles E. Murry, and Ying Zheng
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- 2022
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30. Preliminary study of laser-induced breakdown spectroscopy for Mg/Ca investigation in cultured scallop shells
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Yuandong Li, Yangfan Wang, Shi Wang, Ronger Zheng, Zhenmin Bao, and Yuan Lu
- Subjects
Biomedical Engineering ,Instrumentation ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Abstract
The element ratio of Mg/Ca is a primary proxy in studying the composition of seashells, and laser-induced breakdown spectroscopy (LIBS) is a practical technique for elemental analysis. In this work, we tried to apply LIBS to investigate the Mg/Ca ratio in cultured seashells of two scallop species ( Chlamys farreri and Patinopecten yessoensis). It was found that LIBS was capable of tracking Mg/Ca variation on the cross section of the scallop shell ( Chlamys farreri), and the variation trend was well verified by the measurement of SEM-EDS. Based on this, LIBS detection was carried out for Mg/Ca investigation on another species of the scallop shell ( Patinopecten yessoensis), and the intensity ratio of Mg/Ca presented a similar variation to δ18O measurement under mass spectroscopy. The result also indicated that the LIBS technique is appropriate in the Mg/Ca investigation for scallop shells, and in cultured scallops, the Mg/Ca ratio would be equally useful for tracking temperature variations. In the future, LIBS is expected to be developed as a diagnostic tool in seashell cultivation, and more elemental compositions would be involved in this kind of investigation.
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- 2023
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31. Physical Supporting Devices as Interventions to Reduce Muscular Load of Surgeons in the Operating Room
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Carmen (Jiayang) Li, Yao Zhang, Yuandong Li, and Bin Zheng
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Surgery - Abstract
Introduction Heavy muscle load during operations, caused by static and awkward postures, contributes to the discomfort of surgeons, and imperils surgical quality. We reviewed the supporting devices available to assist surgeons in the operating room and anticipated that physical support devices would help reduce occupational injuries among surgeons and improve surgical performance. Methods A systematic literature review was completed. Papers on supporting devices for intraoperative stress reduction were included. Supported body parts and the impact of these devices on the surgeons’ performance were extracted from the 21 selected papers. Results Among the 21 devices introduced, eleven targeted on the upper extremities, 5 targeted on the lower extremities, and 5 were ergonomic chairs. Nine devices were tested in the operating room, 10 in a lab setting with simulated tasks, and 2 were still in development. The data from 7 studies did not show a significant improvement in stress reduction or surgical quality. With 2 devices still in the development phase, the remaining 12 papers showed promising results. Discussion Although some of the devices were still in testing, most of the research teams believed that physical supporting devices can be useful in reducing muscle load, relieving discomfort, and improving surgical performance intraoperatively.
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- 2023
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32. Robust Spontaneous Raman Flow Cytometry for Single‐Cell Metabolic Phenome Profiling via pDEP‐DLD‐RFC
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Xixian Wang, Lihui Ren, Zhidian Diao, Yuehui He, Jiaping Zhang, Min Liu, Yuandong Li, Lijun Sun, Rongze Chen, Yuetong Ji, Jian Xu, and Bo Ma
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General Chemical Engineering ,General Engineering ,General Physics and Astronomy ,Medicine (miscellaneous) ,General Materials Science ,Biochemistry, Genetics and Molecular Biology (miscellaneous) - Published
- 2023
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33. Comprehensive Analysis of Sinonasal Inverted Papilloma Expression Profiles Identifies Long Non-Coding RNA AKTIP as a Potential Biomarker
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Hanyi He, Xinlu Wang, Yueyue Lu, Xiaojiang Lin, Yuandong Li, Yong Li, Zhihong Lin, Zhiqi Ma, Xiaolin Cao, and Yaoshu Teng
- Subjects
inverted papilloma ,Genetics ,biomarker ,Molecular Medicine ,long noncoding RNA ,bioinformatics ,QH426-470 ,expression profiles ,Genetics (clinical) - Abstract
Long noncoding RNAs (lncRNAs) are a novel class of potential biomarkers and therapeutic targets for the treatment of neoplasms. The purpose of this study was to explore the expression profile, potential functions, and diagnostic and clinical significance of lncRNAs in sinonasal inverted papilloma (SNIP). The expression profiles of lncRNAs and mRNAs were analyzed using a microarray. The potential functions and clinical implications of specific lncRNAs were further analyzed by bioinformatics and statistical methods. Microarray analysis identified 1,668 significantly upregulated and 1,767 downregulated lncRNAs in SNIP. Several mRNAs coexpressed with lncRNAs were enriched in some biological processes and cellular signaling pathways related to tumorigenesis. Lnc-AKTIP might interact with a variety of tumor-associated proteins and transcription factors, such as PCBP2, IRF-1, and p53. Receiver operating characteristic curve analysis for lnc-AKTIP showed an area under the curve of 0.939. Notably, its expression level was significantly decreased in SNIP tissues versus normal tissues and was associated with SNIP staging. Lnc-AKTIP may serve as a valuable diagnostic biomarker and a therapeutic target for SNIP.
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- 2022
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34. Interfacial Characteristics of 6061/AZ31B Composites in Multi-Pass Rolling
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Haokun Yang, Yuandong Li, Jin Qiu, Zhaoxi Song, Guangli Bi, and Hongwei Zhou
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Technology ,Microscopy ,QC120-168.85 ,6061 aluminum alloy ,AZ31B magnesium alloy ,multi-pass rolling ,interface organization ,mechanical property ,QH201-278.5 ,Engineering (General). Civil engineering (General) ,TK1-9971 ,Descriptive and experimental mechanics ,General Materials Science ,Electrical engineering. Electronics. Nuclear engineering ,TA1-2040 - Abstract
An Al 6061/Mg AZ31B composite plate with good bonding and excellent comprehensive mechanical properties was prepared through solid-liquid cast-rolling bonding (SLCRB). The microstructure evolution and mechanical behavior of Al/Mg composite plates under different rolling passes were studied. The results showed that with the increase of rolling passes, the bonding layer of the composite plate was crushed, and the base material on both sides of the substrate gradually grew towards the broken part of the bonding layer. The microstructure on both sides of the substrate extended along the rolling direction and was dynamically recrystallized to a certain extent. In the Mg substrate, because the preheating temperature was higher than its recrystallization temperature, with the increase of rolling passes, the grains in Mg substrate were crystallized. When the rolling passes reached the fourth pass, complete recrystallization basically took place in the Mg substrate. With the change of the internal structure and bonding layer on both sides of the substrate, the mechanical properties of the composite plate can be improved gradually. The tensile strength increased from 136 MPa before rolling to 190 MPa at the fourth pass, and the shear strength increased from 74 MPa to 98 MPa, with growth rates of about 40% and 32%, respectively. The elongation of the composite plate decreased from 6.3% to 5.4%, a decrease of about 1%.
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- 2022
35. Feasibility Analysis of Wearables Guiding Scientific Movements and Promoting Health
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Guanghua Tao, Wei Suo, and Yuandong Li
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Wearable Electronic Devices ,Article Subject ,Movement ,Biomedical Engineering ,Feasibility Studies ,Humans ,Health Informatics ,Surgery ,Health Promotion ,Neural Networks, Computer ,Algorithms ,Biotechnology - Abstract
Wearable devices have gradually integrated into people’s healthy lives because of their mobility, portability, and other characteristics, and have shown their value and status in sports and health. Wearable devices can be used to capture a large amount of human body activity data, but how to effectively use these data to serve people and help people form a healthy lifestyle is a problem to be considered. In order to further study the feasibility of wearable devices to guide scientific movements and promote health, a new layered motion recognition algorithm is proposed in this study. In this study, a C4.5-based decision tree algorithm is used to identify the state layer, and only the mean and variance features are extracted from the acceleration sensor data. Three corresponding BP neural network classifiers are constructed and classified. Each classifier is responsible for identifying actions in the corresponding states and verifying the method in this study through experiments. The experimental results in this study show that the recognition rate of the mRMR feature selection recognition algorithm is 1.13% higher than the BE algorithm and 2.02% higher than the recognition method without any feature selection algorithm. In addition, the research in this article found that wearable devices can realize the real-time detection of the physiological indicators of the wearer throughout the day to evaluate the efficacy of the drug and apply it to the early detection and treatment of diseases, which may improve patient compliance and promote health to a certain extent.
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- 2022
36. Evaluation of a Subnanosecond Clock and Data Recovery Technique Via Matlab Simulink and Opti-System Co-Simulation
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Heng Zhang, Yuandong Li, Wenhe Yin, Yuan Du, and LI DU
- Subjects
History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2022
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37. A Method for Solving Percolation Overflow Boundary Based on Maximum of Horizontal Energy Loss Rate
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Yuandong Li, Bing Hao, Xiaojun Li, Liguo Jin, Qing Dong, and Zhenghua Zhou
- Subjects
seepage field finite element calculation ,Science ,Computation ,Boundary (topology) ,Mechanics ,overflow boundary ,Finite element method ,analytical solution ,functional ,Hydraulic head ,Approximation error ,Free surface ,General Earth and Planetary Sciences ,Point (geometry) ,Node (circuits) ,horizontal energy loss rate ,Mathematics - Abstract
The determination of overflow boundary is a prerequisite for the accurate solution of the seepage field by the finite element method. In this paper, a method for solving overflow boundary according to the maximum value of horizontal energy loss rate is proposed, which based on the analysis of the physical meaning of functional and the water head distribution of seepage field under different overflow boundaries. This method considers that the overflow boundary that makes the horizontal energy loss rate reach the maximum value is the real boundary overflow. Compared with the previous iterative computation method of overflow point and free surface, the method of solving overflow boundary based on the maximum horizontal energy loss rate does not need iteration, so the problem of non-convergence does not exist. The relative error of the overflow points is only 1.54% and 0.98% by calculating the two-dimensional model of the glycerol test and the three-dimensional model of the electric stimulation test, respectively. Compared with the overflow boundary calculated by the node virtual flow method, improved cut-off negative pressure method, initial flow method, and improved discarding element method, this method has a higher accuracy.
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- 2021
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38. Comprehensive Analysis of Sinonasal Inverted Papilloma Expression Profiles Identified Long Noncoding RNA AKTIP as a Potential Biomarker
- Author
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Hanyi He, Xinlu Wang, Yueyue Lu, Xiaojiang Lin, Yuandong Li, Yong Li, Zhihong Lin, Zhiqi Ma, Xiaolin Cao, and Yaoshu Teng
- Abstract
Background: Long noncoding RNAs (lncRNAs) are a novel class of potential biomarkers and therapeutic targets for the treatment of neoplasms. The purpose of this study was to explore the expression profile, potential functions, and diagnostic and clinicopathological significance of lncRNAs in sinonasal inverted papilloma (SNIP).Methods The expression profiles of lncRNAs and mRNAs were analyzed using a microarray. The potential functions and clinical implications of specific lncRNAs were further analyzed by bioinformatics and statistical methods.Results Microarray analysis identified 1,668 significantly upregulated and 1,767 downregulated lncRNAs in SNIP. Several mRNAs coexpressed with lncRNAs were enriched in some biological processes and cellular signaling pathways related to tumorigenesis. Lnc-AKTIP might interact with a variety of tumor-associated proteins and transcription factors, such as PCBP2, IRF-1, and p53.Receiver operating characteristic curve analysis for lnc-AKTIP showed an area under the curve of 0.939. Notably, its expression level was significantly decreased in SNIP tissues versus normal tissues and was associated with SNIP staging.Conclusion Lnc-AKTIP may serve as a valuable diagnostic biomarker and a therapeutic target for SNIP.
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- 2021
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39. Single-cell sorting of marine plankton based on micro-optical tweezers
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Caiyun Miao, Jia Yu, Huiping Liu, Lingyan Kan, and Yuandong Li
- Subjects
Experimental system ,Optical tweezers ,Computer science ,Microfluidics ,Tweezers ,Sorting ,Upstream (networking) ,Plankton ,Cell sorting ,Biological system - Abstract
Marine plankton are micro and diverse, and most of them are still non-cultivable. So single-cell analysis, focused on the study of diversity and heterogeneity of their cells, has become a hot issue in marine microbiology research, which relies on sound single-cell preparation technology for upstream operations. By combining micro-optical tweezers technology with microfluidic droplet wrapping technology, we developed a fluorescence microscopic optical tweezers system for plankton sorting. Our system consists of a micro-optical tweezers module, a fluorescence module, an imaging module and a sorting module. Using this system, we conduct single-cell observation, monitoring, capture manipulation, separation and extraction of microplankton in seawater samples. The specific process is as follows: 1. Prepare samples, including grading filtration and enrichment of seawater sampled in Qingdao offshore. 2. Observe and select the target single-cell with a specific sorting chip on the microscopic optical tweezers single-cell sorting system. And perform visualized microdroplet single-cell sorting through optical tweezers capture manipulation. 3. Take out the target living single-cell after forming microdroplets. Using our experimental system, we are able to provide precise technical support for downstream experiments including single-cell culture, sequencing and monoclonality. In addition, our method has the advantages of flexible operation, intact cells and visualization as "what you see is what you get". Meanwhile, it has a 100% single-cell acquisition rate while maintaining the high viability of the sorted cell.
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- 2021
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40. Investigating the minimum detectable activity concentration and contributing factors in airborne gamma-ray spectrometry
- Author
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Xiao-Zhong Han, Zhong-Xiang Lin, Liangquan Ge, Qingxian Zhang, Yi Gu, Xuan Guan, Wanchang Lai, Yuandong Li, and Kun Sun
- Subjects
Nuclear and High Energy Physics ,Materials science ,Resolution (mass spectrometry) ,Physics::Instrumentation and Detectors ,Monte Carlo method ,Analytical chemistry ,Thorium ,chemistry.chemical_element ,Uranium ,Mass spectrometry ,Nuclear Energy and Engineering ,Volume (thermodynamics) ,chemistry ,Scintillation counter ,Calibration - Abstract
In this study, the theory of minimum detectable activity concentration (MDAC) for airborne gamma-ray spectrometry (AGS) was derived, and the relationship between the MDAC and the intrinsic efficiency of a scintillation counter, volume, and energy resolution of scintillation crystals, and flight altitude of an aircraft was investigated. To verify this theory, experimental devices based on NaI and CeBr3 scintillation counters were prepared, and the potassium, uranium, and thorium contents in calibration pads obtained via the stripping ratio method and theory were compared. The MDACs of AGS under different conditions were calculated and analyzed using the proposed theory and the Monte Carlo method. The relative errors found via a comparison of the experimental and theoretical results were less than 4%. The theory of MDAC can guide the work of AGS in probing areas with low radioactivity.
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- 2021
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41. MiR-143-3p suppresses the progression of nasal squamous cell carcinoma by targeting Bcl-2 and IGF1R
- Author
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Yuandong Li, Yong Li, Ming Guan, Yueqiu Gao, Yaoshu Teng, Yi Qian, Xiaojiang Lin, and Xiaolin Cao
- Subjects
Male ,0301 basic medicine ,Nose Neoplasms ,Biophysics ,Biochemistry ,Receptor, IGF Type 1 ,Flow cytometry ,03 medical and health sciences ,0302 clinical medicine ,Downregulation and upregulation ,Cell Movement ,Cell Line, Tumor ,microRNA ,medicine ,Humans ,Molecular Biology ,Cell Proliferation ,Insulin-like growth factor 1 receptor ,medicine.diagnostic_test ,Cell growth ,Chemistry ,Cell Biology ,Middle Aged ,Cell cycle ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,030104 developmental biology ,Proto-Oncogene Proteins c-bcl-2 ,Apoptosis ,Cell culture ,030220 oncology & carcinogenesis ,Carcinoma, Squamous Cell ,Disease Progression ,Cancer research ,Female - Abstract
Dysregulated microRNAs (miRNAs) play crucial roles in the occurrence and development of multiple tumours, but their roles in the progression of nasal squamous cell carcinoma (NSCC) remain unknown. The aim of our study was to investigate the potential function and molecular mechanism of miR-143-3p in NSCC. Expression of miRNA and mRNA was detected by quantitative real-time reverse transcription-PCR (qRT-PCR). Forced overexpression of miR-143-3p was established by transfecting mimics into NSCC cell line. Then, we investigated the role of miR-143-3p in human NSCC cell proliferation, apoptosis, cycle and migration by using MTT, flow cytometry and transwell assays. Bioinformatics analysis, qRT-PCR, Western blot and luciferase reporter analysis were performed to validate the relationship between miR-143-3p and its potential targets. We found that miR-143-3p was substantially downregulated in human NSCC tissues and cell line. Forced upregulation of miR-143-3p significantly attenuated cell proliferation and migration. Furthermore, this change could induce apoptosis and G1-phase arrest of NSCC cells. Mechanistically, miR-143-3p directly targeted and significantly suppressed Bcl-2 and IGF1R expression. In summary, miR-143-3p regulation of the proliferation, apoptosis, cell cycle and migration of NSCC probably partly depends on inhibition of Bcl-2 and IGF1R, indicating that miR-143-3p may be a novel molecular therapeutic target for NSCC.
- Published
- 2019
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42. Pericyte constriction underlies capillary derecruitment during hyperemia in the setting of arterial stenosis
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Wei Wei, Nabil J. Alkayed, Carmen Methner, Sanjiv Kaul, Ruikang K. Wang, N. David Yanez, Anusha Mishra, Jeffrey J. Iliff, Yuandong Li, Kirsti Golgotiu, and Berislav V. Zlokovic
- Subjects
Male ,medicine.medical_specialty ,Physiology ,Ischemia ,Hyperemia ,Mice, Transgenic ,Constriction, Pathologic ,Constriction ,Receptor, Platelet-Derived Growth Factor beta ,Mice ,Peripheral Arterial Disease ,Physiology (medical) ,Internal medicine ,Animals ,Medicine ,Ligation ,business.industry ,Arterial stenosis ,Cardiac ischemia ,Angiography ,medicine.disease ,Capillaries ,Femoral Artery ,Vasodilation ,Disease Models, Animal ,Luminescent Proteins ,Stenosis ,Microscopy, Fluorescence, Multiphoton ,medicine.anatomical_structure ,Regional Blood Flow ,Vasoconstriction ,Gracilis Muscle ,Mutation ,cardiovascular system ,Cardiology ,Female ,Pericyte ,Pericytes ,Cardiology and Cardiovascular Medicine ,business ,Perfusion ,Research Article ,circulatory and respiratory physiology - Abstract
Capillary derecruitment distal to a coronary stenosis is implicated as the mechanism of reversible perfusion defect and potential myocardial ischemia during coronary hyperemia; however, the underlying mechanisms are not defined. We tested whether pericyte constriction underlies capillary derecruitment during hyperemia under conditions of stenosis. In vivo two-photon microscopy (2PM) and optical microangiography (OMAG) were used to measure hyperemia-induced changes in capillary diameter and perfusion in wild-type and pericyte-depleted mice with femoral artery stenosis. OMAG demonstrated that hyperemic challenge under stenosis produced capillary derecruitment associated with decreased RBC flux. 2PM demonstrated that hyperemia under control conditions induces 26 ± 5% of capillaries to dilate and 19 ± 3% to constrict. After stenosis, the proportion of capillaries dilating to hyperemia decreased to 14 ± 4% ( P = 0.05), whereas proportion of constricting capillaries increased to 32 ± 4% ( P = 0.05). Hyperemia-induced changes in capillary diameter occurred preferentially in capillary segments invested with pericytes. In a transgenic mouse model featuring partial pericyte depletion, only 14 ± 3% of capillaries constricted to hyperemic challenge after stenosis, a significant reduction from 33 ± 4% in wild-type littermate controls ( P = 0.04). These results provide for the first time direct visualization of hyperemia-induced capillary derecruitment distal to arterial stenosis and demonstrate that pericyte constriction underlies this phenomenon in vivo. These results could have important therapeutic implications in the treatment of exercise-induced ischemia. NEW & NOTEWORTHY In the setting of coronary arterial stenosis, hyperemia produces a reversible perfusion defect resulting from capillary derecruitment that is believed to underlie cardiac ischemia under hyperemic conditions. We use optical microangiography and in vivo two-photon microscopy to visualize capillary derecruitment distal to a femoral arterial stenosis with cellular resolution. We demonstrate that capillary constriction in response to hyperemia in the setting of stenosis is dependent on pericytes, contractile mural cells investing the microcirculation.
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- 2019
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43. Microstructure and mechanical properties of an extruded Mg-Dy-Ni alloy
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Dong Qiu, Guangli Bi, Yuxiang Han, J. L. Jiang, Yuandong Li, Duyao Zhang, and Mark Alan Easton
- Subjects
010302 applied physics ,Yield (engineering) ,Materials science ,Precipitation (chemistry) ,Mechanical Engineering ,Alloy ,02 engineering and technology ,engineering.material ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Microstructure ,01 natural sciences ,Precipitation hardening ,Mechanics of Materials ,Phase (matter) ,0103 physical sciences ,Ultimate tensile strength ,engineering ,General Materials Science ,Composite material ,0210 nano-technology ,Tensile testing - Abstract
The microstructure and mechanical properties of an extruded Mg-12Dy-1.1Ni alloy have been investigated in this paper. The microstructure of the as-extruded alloy consisted of α-Mg matrix, Mg2Dy phase and a lamellar long-period stacking order (LPSO) phase distributed along the extrusion direction. Ageing the extruded alloy at 250 °C showed double peaks at 54 h and 108 h during ageing. The first ageing peak was due to a high number density of blocky 18R LPSO phases in conjunction with the precipitation of underaged 14H LPSO phase. The second ageing peak mainly arose from the precipitation of high volume fraction of 14H LPSO phases in the grain interior. Tensile testing indicated that the extruded alloy aged for 108 h exhibited the highest yield and ultimate tensile strengths from room temperature to 300 °C. The high tensile strengths of the alloy are mainly attributed to grain refinement and precipitation strengthening of 14H LPSO phase and dispersion strengthening of blocky 18R LPSO phase.
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- 2019
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44. Monitoring Acute Stroke Progression: Multi-Parametric OCT Imaging of Cortical Perfusion, Flow, and Tissue Scattering in a Mouse Model of Permanent Focal Ischemia
- Author
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Yuandong Li, Ruikang K. Wang, and Woo June Choi
- Subjects
Male ,medicine.medical_specialty ,Ischemia ,Infarction ,Article ,Brain Ischemia ,030218 nuclear medicine & medical imaging ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Optical coherence tomography ,Internal medicine ,Image Interpretation, Computer-Assisted ,medicine ,Animals ,Electrical and Electronic Engineering ,Stroke ,Radiological and Ultrasound Technology ,medicine.diagnostic_test ,business.industry ,Penumbra ,Brain ,Blood flow ,medicine.disease ,Computer Science Applications ,Mice, Inbred C57BL ,Disease Models, Animal ,Cerebral blood flow ,Cerebrovascular Circulation ,Disease Progression ,Cardiology ,business ,Perfusion ,Algorithms ,Tomography, Optical Coherence ,Software - Abstract
Cerebral ischemic stroke causes injury to brain tissue characterized by a complex cascade of neuronal and vascular events. Imaging during the early stages of its development allows prediction of tissue infarction and penumbra so that optimal intervention can be determined in order to salvage brain function impairment. Therefore, there is a critical need for novel imaging techniques that can characterize brain injury in the earliest phases of the ischemic stroke. This paper examined optical coherence tomography (OCT) for imaging acute injury in experimental ischemic stroke in vivo . Based on endogenous optical scattering signals provided by OCT imaging, we have developed a single, integrated imaging platform enabling the measurement of changes in blood perfusion, blood flow, erythrocyte velocity, and light attenuation within a cortical tissue, during focal cerebral ischemia in a mouse model. During the acute phase (from 5 min to the first few hours following the blood occlusion), the multi-parametric OCT imaging revealed multiple hemodynamic and tissue scattering responses in vivo , including cerebral blood flow deficits, capillary non-perfusion, displacement of penetrating vessels, and increased light attenuation in the cortical tissue at risk that are spatially correlated with the infarct core, as determined by postmortem staining with triphenyltetrazolium chloride. The use of multi-parametric OCT imaging may aid in the comprehensive evaluation of ischemic lesions during the early stages of stroke, thereby providing essential knowledge for guiding treatment decisions.
- Published
- 2019
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45. Single passband microwave photonic filter with widely tuning range based on optical injected distributed feedback semiconductor laser
- Author
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Tao Pu, Yuan Liu, Meng Hu, Zhou Hua, Zhou Feng, Jilin Zheng, Peng Xiang, Yuandong Li, and Huatao Zhu
- Subjects
Quantum optics ,Frequency response ,Distributed feedback laser ,Materials science ,Sideband ,business.industry ,Laser ,Atomic and Molecular Physics, and Optics ,law.invention ,Wavelength ,law ,Optical Carrier transmission rates ,Optoelectronics ,business ,Passband - Abstract
A novel widely tunable single passband microwave photonic filter (MPF) is proposed and experimentally demonstrated, which is based on a carrier-suppressed double sidebands (CS-DSB) optical signal injected into an distributed feedback (DFB) laser. A polarization modulator (PolM) and a polarization beam splitter (PBS) are exploited to generate the CS-DSB optical signal. When the CS-DSB optical signal is injected into the DFB laser, due to the frequency selective gain feature of optical injected DFB laser, one sideband of the CS-DSB optical signal is selected and amplified. Beating the amplified sideband with the optical carrier, the gain spectrum of the DFB laser is mapped to the frequency response of the MPF. The MPF can be tuned by adjusting the wavelength of the DFB laser. Experiment results show that the MPF can be tuned from 0 to 40 GHz by changing the working temperature of the DFB laser.
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- 2019
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46. MrArk1, an actin-regulating kinase gene, is required for endocytosis and involved in sustaining conidiation capacity and virulence in Metarhizium robertsii
- Author
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Yuandong Li, Jianyu Feng, Zhangxun Wang, Bo Huang, and Yuanyuan Jiang
- Subjects
Metarhizium ,Genes, Fungal ,Mutant ,Kinesins ,Conidiation ,Virulence ,Protein Serine-Threonine Kinases ,Biology ,Endocytosis ,Applied Microbiology and Biotechnology ,Fungal Proteins ,03 medical and health sciences ,Gene Expression Regulation, Fungal ,Animals ,030304 developmental biology ,0303 health sciences ,Appressorium ,030306 microbiology ,Kinase ,fungi ,General Medicine ,Spores, Fungal ,biology.organism_classification ,Cell biology ,Lepidoptera ,Galleria mellonella ,Mutation ,Entomopathogenic fungus ,Biological Assay ,Biotechnology - Abstract
Actin-regulating kinase (Ark) plays an important role in controlling endocytosis, which has been shown to be involved in the development and virulence of several fungal pathogens. However, it remains unclear whether Ark1 is required for the development and pathogenicity of an entomopathogenic fungus. Here, MrArk1 (MAA_03415), a homologue of yeast Ark1, was characterized in the insect pathogenic fungus, Metarhizium robertsii. Disruption of MrArk1 led to defects in endocytosis and a marked reduction (58%) in conidiation capacity. The reduced conidiation level was accompanied by repression of several key conidiation-related genes, including brlA, abaA, and wetA. Additionally, the deletion mutant showed a significant decrease in its tolerance to heat shock, but not to UV-B irradiation. Bioassays demonstrated attenuated virulence for the deletion mutant against Galleria mellonella via normal cuticle infection, accompanied by suppressed appressorium formation and reduced transcript levels of several genes involved in cuticle penetration. Taken together, our results indicate that MrArk1 is involved in the heat tolerance, sporulation, and virulence of M. robertsii, and thus is an important factor for sustaining the fungal potential against insect pests.
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- 2019
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47. Microstructure and Mechanical Properties of Extruded Mg-7Sn-5Zn-xAl (x = 0, 1, 2 and 3 wt.%) Alloy
- Author
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Tingqu Li, Cao Chi, J. L. Jiang, Guangli Bi, Ying Ma, Fengyun Yan, and Yuandong Li
- Subjects
010302 applied physics ,Materials science ,Mechanical Engineering ,Alloy ,02 engineering and technology ,engineering.material ,021001 nanoscience & nanotechnology ,Microstructure ,01 natural sciences ,Grain size ,Precipitation hardening ,Mechanics of Materials ,0103 physical sciences ,Ultimate tensile strength ,engineering ,Dynamic recrystallization ,General Materials Science ,Extrusion ,Composite material ,Elongation ,0210 nano-technology - Abstract
Microstructure and mechanical properties of extruded Mg-7Sn-5Zn-xAl (x = 0, 1, 2 and 3 wt.%) alloy were investigated. The as-cast Mg-7Sn-5Zn alloy mainly comprised α-Mg dendrites, Mg2Sn and nanosized Mg-Zn phases in a Mg matrix, whereas the quasicrystal (icosahedral (I)) phase precipitated with the addition of Al. After extrusion, the grain size decreased due to dynamic recrystallization and the resulting particles were crushed and distributed along the extrusion direction. The highest tensile strength was exhibited by the extruded Mg-7Sn-5Zn-2Al alloy, which had a yield strength, ultimate tensile strength and elongation to failure of 198, 343 MPa and 18.7%, respectively. The high tensile strength was mainly attributed to grain refinement and precipitation strengthening of the Mg2Sn and icosahedral phases.
- Published
- 2019
- Full Text
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48. Adaptive Response and Transcriptomic Analysis of Flax (Linum usitatissimum L.) Seedlings to Salt Stress
- Author
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Yuandong Li, Jiao Chen, Xiao Li, Haixia Jiang, Dongliang Guo, Fang Xie, Zeyang Zhang, and Liqiong Xie
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Genetics ,flax ,salt stress ,adaptive growth ,osmoregulation ,antioxidant properties ,transcriptome analysis ,Genetics (clinical) - Abstract
Soil salinity constrains agricultural development in arid regions. Flax is an economically important crop in many countries, and screening or breeding salinity-resistant flax cultivars is necessary. Based on the previous screening of flaxseed cultivars C71 (salt-sensitive) and C116 (salt-tolerant) as test materials, flax seedlings stressed with different concentrations of NaCl (0, 100, 150, 200, and 250 mmol/L) for 21 days were used to investigate the effects of salt stress on the growth characteristics, osmotic regulators, and antioxidant capacity of these flax seedlings and to reveal the adaptive responses of flax seedlings to salt stress. The results showed that plant height and root length of flax were inhibited, with C116 showing lower growth than C71. The concentrations of osmotic adjustment substances such as soluble sugars, soluble proteins, and proline were higher in the resistant material, C116, than in the sensitive material, C71, under different concentrations of salt stress. Consistently, C116 showed a better rapid scavenging ability for reactive oxygen species (ROS) and maintained higher activities of antioxidant enzymes to balance salt injury stress by inhibiting growth under salt stress. A transcriptome analysis of flax revealed that genes related to defense and senescence were significantly upregulated, and genes related to the growth and development processes were significantly downregulated under salt stress. Our results indicated that one of the important adaptations to tolerance to high salt stress is complex physiological remediation by rapidly promoting transcriptional regulation in flax.
- Published
- 2022
- Full Text
- View/download PDF
49. Quantitative cervical spine injury responses in whiplash loading with a numerical method of natural neural reflex consideration
- Author
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Ziyang Liang, Fuhao MO, Zhefen Zheng, Yuandong Li, Ye Tian, Xiaobing Jiang, and Tang Liu
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Spinal Injuries ,Finite Element Analysis ,Reflex ,Cervical Vertebrae ,Humans ,Health Informatics ,Spinal Diseases ,Software ,Neck ,Whiplash Injuries ,Computer Science Applications ,Biomechanical Phenomena - Abstract
Neural reflex is hypothesized as a regulating step in spine stabilizing system. However, neural reflex control is still in its infancy to consider in the previous finite element analysis of head-neck system for various applications. The purpose of this study is to investigate the influences of neural reflex control on neck biomechanical responses, then provide a new way to achieve an accurate biomechanical analysis for head-neck system with a finite element model.A new FE head-neck model with detailed active muscles and spinal cord modeling was established and globally validated at multi-levels. Then, it was coupled with our previously developed neuromuscular head-neck model to analyze the effects of vestibular and proprioceptive reflexes on biomechanical responses of head-neck system in a typical spinal injury loading condition (whiplash). The obtained effects were further analyzed by comparing a review of epidemiologic data on cervical spine injury situations.The results showed that the active model (AM) with neural reflex control obviously presented both rational head-neck kinematics and tissue injury risk referring to the previous experimental and epidemiologic studies, when compared with the passive model (PM) without it. Tissue load concentration locations as well as stress/strain levels were both changed due to the muscle activation forces caused by neural reflex control during the whole loading process. For the bony structures, the AM showed a peak stress level accounting for only about 25% of the PM. For the discs, the stress concentrated location was transferred from C2-C6 in the PM to C4-C6 in the AM. For the spinal cord, the strain concentrated locations were transferred from C1 segment to around C4 segment when the effects of neural reflex control were implemented, while the gray matter and white matter peak strains were reduced to 1/3 and 1/2 of the PM, respectively. All these were well correlated with epidemiological studies on clinical cervical spine injuries.In summary, the present work demonstrated necessity of considering neural reflex in FE analysis of a head-neck system as well as our model biofidelity. Overall results also verified the previous hypothesis and further quantitatively indicated that the muscle activation caused by neural reflex is providing a protection for the neck in impact loading by decreasing the strain level and changing the possible injury to lower spinal cord level to reduce injury severity.
- Published
- 2021
50. Flexible-width Bit-level Compressor for Convolutional Neural Network
- Author
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Li Du, Yuandong Li, Haoran Geng, Yichuan Bai, Junhan Zhu, Zhongfeng Wang, Yuan Du, and Xiaoliang Chen
- Subjects
business.industry ,Computer science ,Data_CODINGANDINFORMATIONTHEORY ,Huffman coding ,Convolutional neural network ,symbols.namesake ,Compression ratio ,symbols ,Redundancy (engineering) ,business ,Field-programmable gate array ,Throughput (business) ,Decoding methods ,Computer hardware ,Block (data storage) - Abstract
In this paper, a weight compression technique named Flexible-width Bit-level (FWBL) coding is proposed to compress convolutional neural networks (CNN) models without re-training. FWBL splits the weight parameters into independent size-optimized blocks and uses just-enough bits for each block. Bit-level run-length coding is employed on high bits (HBs) to further compress the redundancy due to non-uniformly distributed weights. We implemented a configurable hardware decoder and synthesize it with TSMC 28nm technology. Results show that FWBL achieves an average compression ratio of 1.6 which is close to the Huffman coding. The decoder has a throughput of 3.7GBps running at 1.1GHz, with a power dissipation of 3.55mW, which is 17.9x and 21x better in throughput and energy efficiency compared with the prior work. Implemented in FPGA, our decoder is 3.36x and 4.96x better than various Huffman decoders in throughput and area efficiency, making it a promising weight compression technique for mobile CNN applications.
- Published
- 2021
- Full Text
- View/download PDF
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