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Dimension-Enhanced Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry Combined with Intelligent Peak Annotation for the Rapid Characterization of the Multiple Components from Seeds of Descurainia sophia 被引量:1
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作者 Simiao Wang Xue Li +7 位作者 Boxue Chen Shitong Li Jiali Wang Jing Wang Mingshuo Yang Xiaoyan Xu Hongda Wang Wenzhi Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2022年第3期541-567,共27页
The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components.The seeds of Descurainia sophia(SDS)are utilized in China as a co... The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components.The seeds of Descurainia sophia(SDS)are utilized in China as a cough and asthma relieving agent.Herein,a dimension-enhanced integral approach,by combining ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(UHPLC/IMQTOF-MS)and intelligent peak annotation,was developed to rapidly characterize the multicomponents from SDS.Good chromatographic separation was achieved within 38 min on a UPLC CSH C18(2.1×100 mm,1.7μm)column which was eluted by 0.1%formic acid in water(water phase)and acetonitrile(organic phase).Collision-induced dissociation-MS^(2)data were acquired by the data-independent high-definition MS^(E)(HDMS^(E))in both the negative and positive electrospray ionization modes.A major components knockout strategy was applied to improve the characterization of those minor ingredients by enhancing the injection volume.Moreover,a self-built chemistry library was established,which could be matched by the UNIFI software enabling automatic peak annotation of the obtained HDMS^(E)data.As a result of applying the intelligent peak annotation workflows and further confirmation process,a total of 53 compounds were identified or tentatively characterized from the SDS,including 29 flavonoids,one uridine derivative,four glucosides,one lignin,one phenolic compound,and 17 others.Notably,four-dimensional information related to the structure(e.g.,retention time,collision cross section,MS^(1)and MS^(2)data)was obtained for each component by the developed integral approach,and the results would greatly benefit the quality control of SDS. 展开更多
关键词 Descurainia sophia multicomponent characterization ultra-high performance liquid chromatography ion mobility/quadrupole time-of-flight mass spectrometry high-definition MS^(E) flavonoid
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Analytical computation of magnetic field in coil-dominated superconducting quadrupole magnets based on racetrack coils
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作者 Chuang Shen Ying-Shun Zhu Fu-San Chen 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第4期119-135,共17页
Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and serpentine.However,all three coil configurations have complex spatial geometries,which make magnet manufact... Currently,three types of superconducting quadrupole magnets are used in particle accelerators:cos 2θ,CCT,and serpentine.However,all three coil configurations have complex spatial geometries,which make magnet manufacturing and strain-sensitive superconductor applications difficult.Compared with the three existing quadrupole coils,the racetrack quadrupole coil has a simple shape and manufacturing process,but there have been few theoretical studies.In this paper,the two-dimensional and three-dimensional analytical expressions for the magnetic field in coil-dominated racetrack superconducting quadrupole magnets are presented.The analytical expressions of the field harmonics and gradient are fully resolved and depend only on the geometric parameters of the coil and current density.Then,a genetic algorithm is applied to obtain a solution for the coil geometry parameters with field harmonics on the order of 10^(-4).Finally,considering the practical engineering needs of the accelerator interaction region,electromagnetic design examples of racetrack quadrupole magnets with high gradients,large apertures,and small apertures are described,and the application prospects of racetrack quadrupole coils are analyzed. 展开更多
关键词 Superconducting quadrupole magnet Racetrack coil Multipole field Genetic algorithm Magnetic design
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A Fault-Tolerant Mobility-Aware Caching Method in Edge Computing
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作者 Yong Ma Han Zhao +5 位作者 Kunyin Guo Yunni Xia Xu Wang Xianhua Niu Dongge Zhu Yumin Dong 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第7期907-927,共21页
Mobile Edge Computing(MEC)is a technology designed for the on-demand provisioning of computing and storage services,strategically positioned close to users.In the MEC environment,frequently accessed content can be dep... Mobile Edge Computing(MEC)is a technology designed for the on-demand provisioning of computing and storage services,strategically positioned close to users.In the MEC environment,frequently accessed content can be deployed and cached on edge servers to optimize the efficiency of content delivery,ultimately enhancing the quality of the user experience.However,due to the typical placement of edge devices and nodes at the network’s periphery,these components may face various potential fault tolerance challenges,including network instability,device failures,and resource constraints.Considering the dynamic nature ofMEC,making high-quality content caching decisions for real-time mobile applications,especially those sensitive to latency,by effectively utilizing mobility information,continues to be a significant challenge.In response to this challenge,this paper introduces FT-MAACC,a mobility-aware caching solution grounded in multi-agent deep reinforcement learning and equipped with fault tolerance mechanisms.This approach comprehensively integrates content adaptivity algorithms to evaluate the priority of highly user-adaptive cached content.Furthermore,it relies on collaborative caching strategies based onmulti-agent deep reinforcement learningmodels and establishes a fault-tolerancemodel to ensure the system’s reliability,availability,and persistence.Empirical results unequivocally demonstrate that FTMAACC outperforms its peer methods in cache hit rates and transmission latency. 展开更多
关键词 mobile edge networks mobility fault tolerance cooperative caching multi-agent deep reinforcement learning content prediction
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Mobility edges and localization characteristics in one-dimensional quasiperiodic quantum walk
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作者 崔鑫辉 王慧敏 李志坚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期156-160,共5页
We construct a one-dimensional quasiperiodic quantum walk to investigate the localization–delocalization transition.The inverse participation ratio and Lyapunov exponent are employed as two indexes to determine the m... We construct a one-dimensional quasiperiodic quantum walk to investigate the localization–delocalization transition.The inverse participation ratio and Lyapunov exponent are employed as two indexes to determine the mobility edge, a critical energy to distinguish the energy regions of extended and localized states. The analytical solution of mobility edge is obtained by the Lyapunov exponents in global theory, and the consistency of the two indexes is confirmed. We further study the dynamic characteristics of the quantum walk and show that the probabilities are localized to some specific lattice sites with time evolution. This phenomenon is explained by the effective potential of the Hamiltonian which corresponds to the phase in the coin operator of the quantum walk. 展开更多
关键词 quantum walk mobility edges QUASIPERIODICITY
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Privacy-Preserving Federated Mobility Prediction with Compound Data and Model Perturbation Mechanism
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作者 Long Qingyue Wang Huandong +4 位作者 Chen Huiming Jin Depeng Zhu Lin Yu Li Li Yong 《China Communications》 SCIE CSCD 2024年第3期160-173,共14页
Human mobility prediction is important for many applications.However,training an accurate mobility prediction model requires a large scale of human trajectories,where privacy issues become an important problem.The ris... Human mobility prediction is important for many applications.However,training an accurate mobility prediction model requires a large scale of human trajectories,where privacy issues become an important problem.The rising federated learning provides us with a promising solution to this problem,which enables mobile devices to collaboratively learn a shared prediction model while keeping all the training data on the device,decoupling the ability to do machine learning from the need to store the data in the cloud.However,existing federated learningbased methods either do not provide privacy guarantees or have vulnerability in terms of privacy leakage.In this paper,we combine the techniques of data perturbation and model perturbation mechanisms and propose a privacy-preserving mobility prediction algorithm,where we add noise to the transmitted model and the raw data collaboratively to protect user privacy and keep the mobility prediction performance.Extensive experimental results show that our proposed method significantly outperforms the existing stateof-the-art mobility prediction method in terms of defensive performance against practical attacks while having comparable mobility prediction performance,demonstrating its effectiveness. 展开更多
关键词 federated learning mobility prediction PRIVACY
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Enhanced magnetic anisotropy and high hole mobility in magnetic semiconductor Ga_(1-x-y)Fe_(x)Ni_(y)Sb
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作者 Zhi Deng Hailong Wang +5 位作者 Qiqi Wei Lei Liu Hongli Sun Dong Pan Dahai Wei Jianhua Zhao 《Journal of Semiconductors》 EI CAS CSCD 2024年第1期16-21,共6页
(Ga,Fe)Sb is a promising magnetic semiconductor(MS)for spintronic applications because its Curie temperature(T_(C))is above 300 K when the Fe concentration is higher than 20%.However,the anisotropy constant Ku of(Ga,F... (Ga,Fe)Sb is a promising magnetic semiconductor(MS)for spintronic applications because its Curie temperature(T_(C))is above 300 K when the Fe concentration is higher than 20%.However,the anisotropy constant Ku of(Ga,Fe)Sb is below 7.6×10^(3)erg/cm^(3)when Fe concentration is lower than 30%,which is one order of magnitude lower than that of(Ga,Mn)As.To address this issue,we grew Ga_(1-x-y)Fe_(x)Ni_(y)Sb films with almost the same x(≈24%)and different y to characterize their magnetic and electrical transport properties.We found that the magnetic anisotropy of Ga_(0.76-y)Fe_(0.24)Ni_(y)Sb can be enhanced by increasing y,in which Ku is negligible at y=1.7%but increases to 3.8×10^(5)erg/cm^(3)at y=6.1%(T_(C)=354 K).In addition,the hole mobility(μ)of Ga_(1-x-y)Fe_(x)Ni_(y)Sb reaches 31.3 cm^(2)/(V∙s)at x=23.7%,y=1.7%(T_(C)=319 K),which is much higher than the mobility of Ga_(1-x)Fe_(x)Sb at x=25.2%(μ=6.2 cm^(2)/(V∙s)).Our results provide useful information for enhancing the magnetic anisotropy and hole mobility of(Ga,Fe)Sb by using Ni co-doping. 展开更多
关键词 magnetic semiconductor molecular beam epitaxy Fe-Ni co-doping magnetic anisotropy hole mobility
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Pig Reproductive and Respiratory Syndrome Virus (PRRSV) Does Not Attach to Boar Sperm;It Affects Only the Velocity Pattern and the Mobility Pattern
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作者 Néstor Méndez Palacios Netzi Naidí Mendez Palacios +3 位作者 Felicitas Vázquez Flores José Alfredo Galicia Domínguez Edgar Guadalupe Beltrán Rosas Maximino Méndez Mendoza 《Journal of Biosciences and Medicines》 2024年第4期216-228,共13页
The purpose of the study was to evaluate the sperm viability of semen infected with PRRSV viral particles, observing the effect of the Virus on the motility of boar sperm. The work was carried out at the FMVZ-BUAP Gen... The purpose of the study was to evaluate the sperm viability of semen infected with PRRSV viral particles, observing the effect of the Virus on the motility of boar sperm. The work was carried out at the FMVZ-BUAP Genetics and Reproduction Laboratory. 5 stallions were used. Each sample contained 1 × 10<sup>6</sup> sperm, the PRRS virus strain was ATCC-VR-2332 (0, 10<sup>2</sup>, 10<sup>4</sup> and 10<sup>6</sup> copies of RNA/mL in triplicate), it was observed daily at the CASA;Hamilton Thorne<sup>®</sup>. Cells with MT (P < 0.05) on days 1, 3, 5, 7 and 10 of evaluation with 201 ± 7.3, 167 ± 10.1, 165 ± 14.6, 134 ± 8.2 and 120 ± 8.8, respectively. The % MP between control and virus concentrations (P ≥ 0.05). The LCV on day 1 and 7 PI at 10X<sup>2</sup> and 10X<sup>6</sup> (P < 0.05) vs control. In the Correlation Matrix, where it is observed that there is a correlation between VSL and VAP, VSL and VCL, VCL and ALH, VAP with ALH. There is a correlation of VSL and ALH, STR and ALH. In this study there were (P ≤ 0.01) in the VCL, in the concentrations (10<sup>2</sup>) 162.81 ± 10.65 and (10<sup>6</sup>) 177.12 ± 5.77 vs 193.04 ± 4.62 of control. This indicates that altering these parameters would be related to fertility and the PRRS virus affects the LCV. Regarding the VSL, it was observed that the sperm infected with viruses 10<sup>2</sup>, 10<sup>4</sup> and 10<sup>6</sup> of 48.00 ± 3.38, 49.88 ± 1.83 and 50.55 ± 2.24 Vs. 56.66 ± 1.68 of control respectively, the control would have greater possibilities of fertilizing the oocyte. In this study, it was found (P ≤ 0.01) in the VAP with 102 of 77.26 ± 5.16, 10<sup>4</sup> with 83.35 ± 2.41 and 10<sup>6</sup> with 81.29 ± 3.14 vs the control with 90.56 ± 2.07. Regarding the ALH there is (P < 0.05) a 10<sup>4</sup> with 8.70 ± .26 and 10<sup>6</sup> with 9.64 ± 0.23 vs control 8.50 ± 0.27. The presence of different concentrations of PRRSV in boar semen induces changes in different types of sperm motility. Infection of ejaculates with the PRRS virus affects sperm motility on days 1, 3, 5, 7, and 10 post-infections. 展开更多
关键词 PRRSV Boar Sperms Velocity Pattern and mobility Pattern
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Dual mobility in primary total hip arthroplasty:A temptation from the devil or a blessing from above
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作者 Raymond Klumpp Linda Boerci +1 位作者 Francesco Buonanotte Marco Zeppieri 《World Journal of Orthopedics》 2024年第6期512-519,共8页
Dual mobility(DM)bearings have gained significant attention in the field of total hip arthroplasty(THA)as a valid treatment option in cases of revision for instability after THA whereas its use in primary THA is still... Dual mobility(DM)bearings have gained significant attention in the field of total hip arthroplasty(THA)as a valid treatment option in cases of revision for instability after THA whereas its use in primary THA is still a matter of debate.This manuscript explores the pathology,incidence,diagnosis,treatment options,prognosis,ongoing studies in the literature,and future perspectives related to the use of DM bearings employed in primary THA.DM bearings are primarily designed to address one of the major concerns in THA:Instability of the prosthetic hip.Instability is both for the surgeon and the patient a devastating postoperative complication,leading to significant pain and subsequent apprehension by the patient and may require revision surgeries.The use of DM implants poses the worry of wear-related complications,such as accelerated polyethylene wear and osteolysis,which also pose challenges to long-term implant survival.This technique has seen a steady rise in recent years,with multiple studies reporting favorable outcomes.The incidence of their utilization varies among institutions and surgeons,reflecting differing preferences and patient populations.The diagnosis of instability and wear-related complications in THA often involves clinical assessment,imaging modalities such as X-rays,computed tomography scans,and sometimes advanced imaging techniques like magnetic resonance imaging.DM bearings can be considered as an option when patients present neurologic pathologies such as Parkinson's disease or recurrent dislocations after THA.DM bearings provide an additional articulation point within the implant,facilitating a greater range of motion and inherent stability.This design allows for reduced risk of dislocation and improved functional outcomes.Various implant manufacturers offer different designs and sizes of DM bearings to suit individual patient needs.Current literature suggests that the use of DM bearings in primary THA has demonstrated promising outcomes in terms of enhanced stability,reduced dislocation rates,and improved patient satisfaction.However,long-term studies with larger patient cohorts are necessary to establish the durability and longevity of these implants.Several ongoing studies are investigating the role of DM bearings in primary THA.These studies focus on evaluating longterm implant survivorship,assessing wear patterns,analyzing patient-reported outcomes,and comparing the effectiveness of DM bearings with traditional THA designs.The future of DM bearings in primary THA holds potential for further advancements.Research efforts are aimed at refining implant materials,optimizing designs,and studying the influence of surgical techniques on implant performance.Additionally,continued investigation into the long-term outcomes and cost-effectiveness of DM bearings will play a crucial role in shaping their future use.While further research is warranted,the current evidence supports their potential as a beneficial solution in improving surgical outcomes and patient satisfaction. 展开更多
关键词 Dual mobility First implant Hip arthroplasty Surgical technique Differential diagnosis
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LiMo 2040 Sustainable urban Living and Mobility Concept-Elevator System
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作者 Hugo Gabele Torben Ossendorf 《Journal of Civil Engineering and Architecture》 2024年第1期1-5,共5页
How can individual mobility in urban areas be maintained alongside scooters and cargo bikes if conventional vehicles are foreseeably no longer allowed to enter city centers?And how can urban living be combined with in... How can individual mobility in urban areas be maintained alongside scooters and cargo bikes if conventional vehicles are foreseeably no longer allowed to enter city centers?And how can urban living be combined with individual mobility in a sustainable and socially acceptable way?LiMo-2040 attempts to provide answers to these questions.It follows a holistic approach according to the criteria:As light,as compact and as simple(cost-effective)as possible.Modular e-vehicle concepts(consisting of vehicle cabin and chassis)are known,but have not yet been thought through to their logical conclusion.The LiMo cabin is not only a vehicle cabin,but also a component of a modern high-rise apartment.It therefore requires no parking space and combines urban living and individual mobility sustainably and cost-effectively.If a vehicle is needed,an app can be used to book a chassis that comes along autonomously and waits until the cabin,including its occupants,travels down a sophisticated rail system,docks and autonomously heads for the desired destination. 展开更多
关键词 MODULAR urban mobility SUSTAINABILITY ELEVATOR AUTONOMOUS
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Improvement in Patient Mobility Following Short-Term Rehabilitation in Skilled Nursing Facilities
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作者 Sean R. Silver Jaden A. Silver 《Open Journal of Therapy and Rehabilitation》 2024年第1期52-60,共9页
Background: Mobility in older adults can be impaired after acute illness or hospitalization, and the level of severity can be used as a predictor of one’s ability to return to independent living. Patients are often r... Background: Mobility in older adults can be impaired after acute illness or hospitalization, and the level of severity can be used as a predictor of one’s ability to return to independent living. Patients are often referred to skilled nursing facilities in hopes of improving their mobility. We wanted to prove that rehabilitative services at Skilled Nursing Facilities improve overall outcomes. Methods: We conducted a retrospective analysis of data from 4612 patients admitted for short-term rehabilitation in a large nursing home chain in California. Our aim was to determine whether patients’ mobility scores, as measured by rehabilitative staff, significantly improved by time of discharge compared to their scores at admission. Mobility scores were rated from 1 to 6, with 1 being the most dependent on aid and 6 being the most independent, over a variety of tasks at admission and compared to scores at discharge. Pearson’s correlations were performed to determine if there were significant relationships in the data: the Pearson’s correlation coefficient was used to describe the relationships between patient admission to a skilled nursing facility and medical improvement upon discharge. Results: The study demonstrated a statistically significant improvement in patients’ mobility scores upon discharge, with Medicare insured patients showing on average 57% improvement and Managed Care insured patients showing on average 59% improvement. Additionally, admission scores appeared to be predictive of the patient’s outcome at discharge. Conclusions: The values and consistency of improvement support the use of acute rehabilitative services in skilled nursing facilities. An equation can be formulated that evaluates patients’ estimated mobility statuses upon discharge from facilities based on their conditions on their arrivals. With this, new interventions can be studied and compared to the current standard of care by using these measurements. They can determine if further improvements can be made to increase patient outcomes. 展开更多
关键词 mobility Skilled Nursing Facility Rehabilitative Services Independent Living Healthcare
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Determination of Ten Kinds of Alpha-2 Agonists Residues in Animal Derived Food by UHPLC-Triple Quadrupole/Composite Linear Ion Trap Mass Spectrometry
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作者 Fang LI Xuemei LI +3 位作者 Xiangang LI Sining LIU Sha LIU Ying WANG 《Plant Diseases and Pests》 2024年第1期28-32,共5页
[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived f... [Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food. 展开更多
关键词 Animal derived food α_(2)-receptor agonist Solid-phase extraction Ultra-high performance liquid phase-triple quadrupole/linear ion trap composite mass spectrometry
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High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation
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作者 Hanki Kim Bum Jun Kim +4 位作者 Seungyon Koh Hyo Jin Cho Xuelian Jin Byung Gon Kim Jun Young Choi 《Neural Regeneration Research》 SCIE CAS 2025年第1期107-115,共9页
High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the ex... High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1. 展开更多
关键词 central nervous system damage-associated molecular pattern ethyl pyruvate glycyrhizzin high mobility group box 1 INFLAMMATION neural stem cells NEURODEVELOPMENT oligodendrocyte progenitor cells redox status REGENERATION
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Sustainable Urban Mobility: (A)Synchrony between Subway Systems
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作者 Ana Paula Borba Gonçalves Barros 《Journal of Traffic and Transportation Engineering》 2024年第3期151-161,共11页
The present study analyses the differences between the subways systems of two cities, Lisbon (Portugal) and Brasília (Brazil), verifying the extent to which their subway systems are spatially integrated with the ... The present study analyses the differences between the subways systems of two cities, Lisbon (Portugal) and Brasília (Brazil), verifying the extent to which their subway systems are spatially integrated with the respective urban fabric-which would promote a better synchrony in terms of economy and sustainability. For interpreting the data, the methodology and tools of the Theory of the Social Logic of Space were used, by means of axial maps, researching the relationship between the constructed and empty (public spaces) areas of the urban structures. Based on the findings, meaningful differences between the subway systems and the configuration of urban spaces were observed, as a product of specific design matrixes. In Lisbon, the mobility associated to the subway seems to be encouraged by the integration of the system with the potential for movement provided by the urban tissue (making the secondary centralities articulated with the subway stations more dynamic). In Brasilia, however, there are several difficulties for such mobility, due to the predominant role of the empty spaces in the city which weakens the gathering potential of such areas, despite the fact that such articulation with secondary centralities is also present there. 展开更多
关键词 Urban mobility spatial configuration space syntax subway system.
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Screening for Plant Toxins in Honey and Herbal Beverage by Ultrahigh-Performance Liquid Chromatography-Ion Mobility-Quadrupole Time of Flight Mass Spectrometry
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作者 Qiaozhen Guo Yi Yang +2 位作者 Jiang Li Bing Shao Jing Zhang 《American Journal of Analytical Chemistry》 2022年第3期108-134,共27页
The standards of plant toxins were separated by a C18 column with gradient elution with 0.1% formic acid/water (V/V) and 0.1% formic acid/acetonitrile (V/V) as mobile phase and acquired by ion mobility-quadrupole time... The standards of plant toxins were separated by a C18 column with gradient elution with 0.1% formic acid/water (V/V) and 0.1% formic acid/acetonitrile (V/V) as mobile phase and acquired by ion mobility-quadrupole time of flight mass spectrometry (IM-QTOF MS) in positive ion mode. A database of 308 plant toxins including retention time, collision cross-section (CCS) and its fragment ions was established. Honey dissolved in water or herbal beverage was extracted by acetonitrile and purified with PSA sorbent, and then acquired by ultrahigh-performance liquid chromatography IM-QTOFMS. The acquired data were processed by comparing with the database we established to confirm the target compounds. The average recoveries for samples at two levels ranged from 60.6% - 120.1%, with relative standard deviation (n = 6) less than 25%. The limit of quantitation for plant toxins ranged from 1 - 20 μg/kg. The developed screening method was used in determination of honey, herbal beverage and honey flavored tea beverage samples. The results showed that berberine was detected in one honey with 1 μg/kg and caffeine was present in some beverages with the concentration from 200 and 5500 μg/kg. This method could meet the requirement for rapid screening of plant toxins in honey and herbal beverage. It can be used for the quality control of honey and herbal beverage in enterprises or quality inspection departments. It also can be used in the rapid screening of food poisoning. 展开更多
关键词 SCREENING Plant Toxins HONEY Herbal Beverage Ultrahigh-Performance Liquid Chromatography ion mobility-quadrupole time of Flight Mass Spectrometry
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基于MobileNetV3Small-ECA的水稻病害轻量级识别研究
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作者 袁培森 欧阳柳江 +1 位作者 翟肇裕 田永超 《农业机械学报》 EI CAS CSCD 北大核心 2024年第1期253-262,共10页
为实现水稻病害的轻量化识别与检测,使用ECA注意力机制改进MobileNetV3Small模型,并使用共享参数迁移学习对水稻病害进行智能化轻量级识别和检测。在PlantVillage数据集上进行预训练,将预训练得到的共享参数迁移到对水稻病害识别模型上... 为实现水稻病害的轻量化识别与检测,使用ECA注意力机制改进MobileNetV3Small模型,并使用共享参数迁移学习对水稻病害进行智能化轻量级识别和检测。在PlantVillage数据集上进行预训练,将预训练得到的共享参数迁移到对水稻病害识别模型上微调优化。在开源水稻病害数据集上进行试验测试,试验结果表明,在非迁移学习下,识别准确率达到97.47%,在迁移学习下识别准确率达到99.92%,同时参数量减少26.69%。其次,通过Grad-CAM进行可视化,本文方法与其他注意力机制CBAM和SENET相比,ECA模块生成的结果与图像中病斑的位置和颜色更加一致,表明网络可以更好地聚焦水稻病害的特征,并且通过可视化和各水稻病害分析了误分类原因。本文方法实现了水稻病害识别模型的轻量化,使其能够在移动设备等资源受限的场景中部署,达到快速、高效、便携的目的。同时开发了基于Android的水稻病害识别系统,方便于在边缘端进行水稻病害识别分析。 展开更多
关键词 水稻病害识别 迁移学习 高效通道注意力机制 mobileNetV3Small 移动端部署
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Participants Recruitment for Coverage Maximization by Mobility Predicting in Mobile Crowd Sensing 被引量:1
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作者 Yuanni Liu Xi Liu +2 位作者 Xin Li Mingxin Li Yi Li 《China Communications》 SCIE CSCD 2023年第8期163-176,共14页
Mobile Crowd Sensing(MCS)is an emerging paradigm that leverages sensor-equipped smart devices to collect data.The introduction of MCS also poses some challenges such as providing highquality data for upper layer MCS a... Mobile Crowd Sensing(MCS)is an emerging paradigm that leverages sensor-equipped smart devices to collect data.The introduction of MCS also poses some challenges such as providing highquality data for upper layer MCS applications,which requires adequate participants.However,recruiting enough participants to provide the sensing data for free is hard for the MCS platform under a limited budget,which may lead to a low coverage ratio of sensing area.This paper proposes a novel method to choose participants uniformly distributed in a specific sensing area based on the mobility patterns of mobile users.The method consists of two steps:(1)A second-order Markov chain is used to predict the next positions of users,and select users whose next places are in the target sensing area to form a candidate pool.(2)The Average Entropy(DAE)is proposed to measure the distribution of participants.The participant maximizing the DAE value of a specific sensing area with different granular sub-areas is chosen to maximize the coverage ratio of the sensing area.Experimental results show that the proposed method can maximize the coverage ratio of a sensing area under different partition granularities. 展开更多
关键词 data average entropy human mobility prediction markov chain mobile crowd sensing
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Flexible Large-Area Graphene Films of 50-600 nm Thickness with High Carrier Mobility 被引量:2
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作者 Shiyu Luo Li Peng +13 位作者 Yangsu Xie Xiaoxue Cao Xiao Wang Xiaoting Liu Tingting Chen Zhanpo Han Peidong Fan Haiyan Sun Ying Shen Fan Guo Yuxing Xia Kaiwen Li Xin Ming Chao Gao 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第5期1-14,共14页
Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and o... Bulk graphene nanofilms feature fast electronic and phonon transport in combination with strong light-matter interaction and thus have great potential for versatile applications,spanning from photonic,electronic,and optoelectronic devices to charge-stripping and electromagnetic shielding,etc.However,large-area flexible close-stacked graphene nanofilms with a wide thickness range have yet to be reported.Here,we report a polyacrylonitrile-assisted’substrate replacement’strategy to fabricate large-area free-standing graphene oxide/polyacrylonitrile nanofilms(lateral size~20 cm).Linear polyacrylonitrile chains-derived nanochannels promote the escape of gases and enable macro-assembled graphene nanofilms(nMAGs)of 50-600 nm thickness following heat treatment at 3,000℃.The uniform nMAGs exhibit 802-1,540 cm^(2)V-1s-1carrier mobility,4.3-4.7 ps carrier lifetime,and>1,581 W m^(-1)K^(-1)thermal conductivity(n MAG-assembled 10μm-thick films,mMAGs).nMAGs are highly flexible and show no structure damage even after 1.0×10^(5)cycles of folding-unfolding.Furthermore,n MAGs broaden the detection region of graphene/silicon heterojunction from near-infrared to mid-infrared and demonstrate higher absolute electromagnetic interference(EMI)shielding effectiveness than state-of-the-art EMI materials of the same thickness.These results are expected to lead to the broad applications of such bulk nanofilms,especially as micro/nanoelectronic and optoelectronic platforms. 展开更多
关键词 Flexible large-area graphene nanofilm High carrier mobility Mid-infrared detection Electromagnetic interference shielding Heat transfer
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Mobility-Aware Adaptive Beam Tracking for Vehicles in Mm Wave Communication Networks 被引量:1
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作者 Jin Xu Ying Zhou +2 位作者 Jian Zhang Yuchong Tang Xiaofeng Tao 《China Communications》 SCIE CSCD 2023年第3期161-174,共14页
The millimeter wave(mm Wave)is a potential solution for high data rate communication due to its availability of large bandwidth.However,it is challenging to perform beam tracking in vehicular mm Wave communication sys... The millimeter wave(mm Wave)is a potential solution for high data rate communication due to its availability of large bandwidth.However,it is challenging to perform beam tracking in vehicular mm Wave communication systems due to high mobility and narrow beams.In this paper,an adaptive beam tracking algorithm is proposed to improve the network throughput performance while reducing the training signal overhead.In particular,based on the mobility prediction at base station(BS),a novel frame structure with dynamic bundled timeslot is designed.Moreover,an actor-critic reinforcement learning based algorithm is proposed to obtain the joint optimization of both beam width and the number of bundled timeslots,which makes the beam tracking adapt to the changing environment.Simulation results demonstrate that,compared with the traditional full scan and Kalman filter based beam tracking algorithms,our proposed algorithm can improve the time-averaged throughput by 11.34%and 24.86%respectively.With the newly designed frame structure,it also outperforms beam tracking with conventional frame structure,especially in scenarios with large range of vehicle speeds. 展开更多
关键词 adaptive beam tracking mobility predic-tion dynamic bundled timeslot variable beam width reinforcement learning actor-critic
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Radio Frequency Quadrupole for Bunching Electron Beam: Electromagnetic Field, Particle Velocity Range, and Accuracy at 10 GHz
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作者 Serigne Bira Gueye 《Journal of Electromagnetic Analysis and Applications》 CAS 2023年第1期1-11,共11页
The Radio Frequency Quadrupole (RFQ) accelerator invented by Kapchinskii and Tepliakov can focus, bunch, and accelerate charged-particle beams simultaneously. Typically, it operates at frequencies up to 500 MHz, for l... The Radio Frequency Quadrupole (RFQ) accelerator invented by Kapchinskii and Tepliakov can focus, bunch, and accelerate charged-particle beams simultaneously. Typically, it operates at frequencies up to 500 MHz, for low particle velocities ( β ). The first attempt to design cylindrical RFQ for electrons in the GHz region was done using 3 GHz at Frascati in 1990. In this paper, an analytical approximation of the electromagnetic field is given, and linearized in the beam region for a rectangular Electron Radio Frequency Quadrupole (ERFQ). The differences between the proton-RFQ and the electron-RFQ are discussed. Then, it will be shown that contrary to the quadrupoles for protons or heavy-ions, the ERFQ is suited for electron velocities in the range 0.5 - 0.7 c, and possible applications are given. Finally, it is illustrated, with numerical field computations that this approach gives sufficient accuracy at 10 GHz. 展开更多
关键词 Electron RF quadrupole BUNCHER Linear Accelerator LINAC Beam Injector
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Correction to:Development of short prototype of dual aperture quadrupole magnet for CEPC ring
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作者 Mei Yang Fu-San Chen +4 位作者 Ya-Feng Wu Zhuo Zhang Bao-Gui Yin Bin Na Zhan-Jun Zhang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第7期267-268,共2页
While typesetting the article,in the Figs.13 and 17 there were several errors introduced.The correct Figs.13 and 17 are copied below:The original article has been corrected.
关键词 corrected quadrupole
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