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Progress on Transition Metal Ions Dissolution Suppression Strategies in Prussian Blue Analogs for Aqueous Sodium-/Potassium-Ion Batteries 被引量:2
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作者 Wenli Shu Junxian Li +3 位作者 Guangwan Zhang Jiashen Meng Xuanpeng Wang Liqiang Mai 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第7期142-168,共27页
Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonethel... Aqueous sodium-ion batteries(ASIBs)and aqueous potassium-ion batteries(APIBs)present significant potential for large-scale energy storage due to their cost-effectiveness,safety,and environmental compatibility.Nonetheless,the intricate energy storage mechanisms in aqueous electrolytes place stringent require-ments on the host materials.Prussian blue analogs(PBAs),with their open three-dimensional framework and facile synthesis,stand out as leading candidates for aqueous energy storage.However,PBAs possess a swift capacity fade and limited cycle longevity,for their structural integrity is compromised by the pronounced dis-solution of transition metal(TM)ions in the aqueous milieu.This manuscript provides an exhaustive review of the recent advancements concerning PBAs in ASIBs and APIBs.The dissolution mechanisms of TM ions in PBAs,informed by their structural attributes and redox processes,are thoroughly examined.Moreover,this study delves into innovative design tactics to alleviate the dissolution issue of TM ions.In conclusion,the paper consolidates various strategies for suppressing the dissolution of TM ions in PBAs and posits avenues for prospective exploration of high-safety aqueous sodium-/potassium-ion batteries. 展开更多
关键词 Prussian blue analogs Transition metal ions dissolution Suppression strategies Aqueous sodium-ion batteries Aqueous potassium-ion batteries
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Advancements in medical treatment for pancreatic neuroendocrine tumors:A beacon of hope 被引量:1
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作者 Somdatta Giri Jayaprakash Sahoo 《World Journal of Gastroenterology》 SCIE CAS 2024年第12期1670-1675,共6页
This editorial highlights the remarkable advancements in medical treatment strategies for pancreatic neuroendocrine tumors(pan-NETs),emphasizing tailored approaches for specific subtypes.Cytoreductive surgery and soma... This editorial highlights the remarkable advancements in medical treatment strategies for pancreatic neuroendocrine tumors(pan-NETs),emphasizing tailored approaches for specific subtypes.Cytoreductive surgery and somatostatin analogs(SSAs)play pivotal roles in managing tumors,while palliative options such as molecular targeted therapy,peptide receptor radionuclide therapy,and chemotherapy are reserved for SSA-refractory patients.Gastrinomas,insul-inomas,glucagonomas,carcinoid tumors and VIPomas necessitate distinct thera-peutic strategies.Understanding the genetic basis of pan-NETs and exploring immunotherapies could lead to promising avenues for future research.This review underscores the evolving landscape of pan-NET treatment,offering renewed hope and improved outcomes for patients facing this complex disease. 展开更多
关键词 Pancreatic neuroendocrine tumor Medical management Somatostatin analog IMMUNOTHERAPY EVEROLIMUS
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A comprehensive review of lunar lava tube base construction and field research on a potential Earth test site 被引量:1
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作者 Yujie Feng Peng-Zhi Pan +3 位作者 Xuhai Tang Zhaofeng Wang Yuxin Li Altaf Hussain 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第9期1201-1216,共16页
The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission... The Moon,as the closest celestial body to the Earth,plays a pivotal role in the progression of deep space exploration,and the establishment of research outposts on its surface represents a crucial step in this mission.Lunar lava tubes are special underground caves formed by volcanic eruptions and are considered as ideal natural shelters and scientific laboratories for lunar base construction.This paper begins with an in-depth overview of the geological origins,exploration history,and distribution locations of lunar lava tubes.Subsequently,it delves into the presentation of four distinctive advantages and typical concepts for constructing bases within lava tubes,summarizing the ground-based attempts made thus far in lunar lava tube base construction.Field studies conducted on a lava tube in Hainan revealed rock compositions similar to those found during the Apollo missions and clear lava tube structures,making it a promising analog site.Lastly,the challenges and opportunities encountered in the field of geotechnical engineering regarding the establishment of lunar lava tube bases are discussed,encompassing cave exploration technologies,in-situ testing methods,geomechanical properties under lunar extreme environments,base design and structural stability assessment,excavation and reinforcement techniques,and simulated Earth-based lava tube base. 展开更多
关键词 Lunar lava tube Lunar base construction Extraterrestrial cave exploration Earth analog site
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Oilfield analogy and productivity prediction based on machine learning: Field cases in PL oilfield, China
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作者 Wen-Peng Bai Shi-Qing Cheng +3 位作者 Xin-Yang Guo Yang Wang Qiao Guo Chao-Dong Tan 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2554-2570,共17页
In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this... In the early time of oilfield development, insufficient production data and unclear understanding of oil production presented a challenge to reservoir engineers in devising effective development plans. To address this challenge, this study proposes a method using data mining technology to search for similar oil fields and predict well productivity. A query system of 135 analogy parameters is established based on geological and reservoir engineering research, and the weight values of these parameters are calculated using a data algorithm to establish an analogy system. The fuzzy matter-element algorithm is then used to calculate the similarity between oil fields, with fields having similarity greater than 70% identified as similar oil fields. Using similar oil fields as sample data, 8 important factors affecting well productivity are identified using the Pearson coefficient and mean decrease impurity(MDI) method. To establish productivity prediction models, linear regression(LR), random forest regression(RF), support vector regression(SVR), backpropagation(BP), extreme gradient boosting(XGBoost), and light gradient boosting machine(Light GBM) algorithms are used. Their performance is evaluated using the coefficient of determination(R^(2)), explained variance score(EV), mean squared error(MSE), and mean absolute error(MAE) metrics. The Light GBM model is selected to predict the productivity of 30 wells in the PL field with an average error of only 6.31%, which significantly improves the accuracy of the productivity prediction and meets the application requirements in the field. Finally, a software platform integrating data query,oil field analogy, productivity prediction, and knowledge base is established to identify patterns in massive reservoir development data and provide valuable technical references for new reservoir development. 展开更多
关键词 Data mining technique Analogy parameters Oilfield analogy Productivity prediction Software platform
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Trifunctional robust electrocatalysts based on 3D Fe/N-doped carbon nanocubes encapsulating Co4N nanoparticles for efficient battery-powered water electrolyzers
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作者 Hyung Wook Choi Hongdae Lee +8 位作者 Jun Lu Seok Bin Kwon Dong In Jeong Beum Jin Park Jiwon Kim Bong Kyun Kang Gun Jang Dae Ho Yoon Ho Seok Park 《Carbon Energy》 SCIE EI CAS CSCD 2024年第6期124-139,共16页
Herein,we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs,where Co_(4)N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize... Herein,we have designed a highly active and robust trifunctional electrocatalyst derived from Prussian blue analogs,where Co_(4)N nanoparticles are encapsulated by Fe embedded in N-doped carbon nanocubes to synthesize hierarchically structured Co_(4)N@Fe/N-C for rechargeable zinc-air batteries and overall water-splitting electrolyzers.As confirmed by theoretical and experimental results,the high intrinsic oxygen reduction reaction,oxygen evolution reaction,and hydrogen evolution reaction activities of Co_(4)N@Fe/N-C were attributed to the formation of the heterointerface and the modulated local electronic structure.Moreover,Co_(4)N@Fe/N-C induced improvement in these trifunctional electrocatalytic activities owing to the hierarchical hollow nanocube structure,uniform distribution of Co_(4)N,and conductive encapsulation by Fe/N-C.Thus,the rechargeable zinc-air battery with Co_(4)N@Fe/N-C delivers a high specific capacity of 789.9 mAh g^(-1) and stable voltage profiles over 500 cycles.Furthermore,the overall water electrolyzer with Co_(4)N@Fe/N-C achieved better durability and rate performance than that with the Pt/C and IrO2 catalysts,delivering a high Faradaic efficiency of 96.4%.Along with the great potential of the integrated water electrolyzer powered by a zinc-air battery for practical applications,therefore,the mechanistic understanding and active site identification provide valuable insights into the rational design of advanced multifunctional electrocatalysts for energy storage and conversion. 展开更多
关键词 battery-powered electrolyzers hierarchical structure Prussian blue analog trifunctional electrocatalyst zinc-air battery
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An analogical study of wave equations,physical quantities,conservation and reciprocity equations between electromagnetic and elastic waves
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作者 Yuchen Zang 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第11期296-304,共9页
This paper presents an analogical study between electromagnetic and elastic wave fields,with a one-to-one correspondence principle established regarding the basic wave equations,the physical quantities and the differe... This paper presents an analogical study between electromagnetic and elastic wave fields,with a one-to-one correspondence principle established regarding the basic wave equations,the physical quantities and the differential operations.Using the electromagnetic-to-elastic substitution,the analogous relations of the conservation laws of energy and momentum are investigated between these two physical fields.Moreover,the energy-based and momentum-based reciprocity theorems for an elastic wave are also derived in the time-harmonic state,which describe the interaction between two elastic wave systems from the perspectives of energy and momentum,respectively.The theoretical results obtained in this analysis can not only improve our understanding of the similarities of these two linear systems,but also find potential applications in relevant fields such as medical imaging,non-destructive evaluation,acoustic microscopy,seismology and exploratory geophysics. 展开更多
关键词 analogical study electromagnetic waves elastic waves wave equations physical quantities conservation laws reciprocity theorems
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Discovery of a geomorphological analog to Martian araneiforms in the Qaidam Basin, Tibetan Plateau
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作者 Shengxing Zhang Yiliang Li Wei Leng 《中国科学技术大学学报》 CAS CSCD 北大核心 2024年第5期1-9,I0006,共10页
Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2) ice was proposed as an explanation for their for... Araneiforms are spider-like ground patterns that are widespread in the southern polar regions of Mars.A gas erosion process driven by the seasonal sublimation of CO_(2) ice was proposed as an explanation for their formation,which cannot occur on Earth due to the high climatic temperature.In this study,we propose an alternative mechanism that attrib-utes the araneiform formation to the erosion of upwelling salt water from the subsurface,relying on the identification of the first terrestrial analog found in a playa of the Qaidam Basin on the northern Tibetan Plateau.Morphological analysis indicates that the structures in the Qaidam Basin have fractal features comparable to araneiforms on Mars.A numerical model is developed to investigate the araneiform formation driven by the water-diffusion mechanism.The simulation res-ults indicate that the water-diffusion process,under varying ground conditions,may be responsible for the diverse aranei-form morphologies observed on both Earth and Mars.Our numerical simulations also demonstrate that the orientations of the saltwater diffusion networks are controlled by pre-existing polygonal cracks,which is consistent with observations of araneiforms on Mars and Earth.Our study thus suggests that a saltwater-related origin of the araneiform is possible and has significant implications for water searches on Mars. 展开更多
关键词 araneiform landform subsurface water Qaidam Basin Mars analog fractal simulations
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Quantifying the chemical composition of weathering products of Hainan basalts with reflectance spectroscopy and its implications for Mars
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作者 Xing Wu JiaCheng Liu +5 位作者 WeiChao Sun Yang Liu Joseph Michalski Wei Tan XiaoRong Qin YongLiao Zou 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期854-867,共14页
With the development of the hyperspectral remote sensing technique,extensive chemical weathering profiles have been identified on Mars.These weathering sequences,formed through precipitation-driven leaching processes,... With the development of the hyperspectral remote sensing technique,extensive chemical weathering profiles have been identified on Mars.These weathering sequences,formed through precipitation-driven leaching processes,can reflect the paleoenvironments and paleoclimates during pedogenic processes.The specific composition and stratigraphic profiles mirror the mineralogical and chemical trends observed in weathered basalts on Hainan Island in south China.In this study,we investigated the laboratory reflectance spectra of a 53-m-long drilling core of a thick basaltic weathering profile collected from Hainan Island.We established a quantitative spectral model by combining the genetic algorithm and partial least squares regression(GA-PLSR)to predict the chemical properties(SiO2,Al2O3,Fe2O3)and index of laterization(IOL).The entire sample set was divided into a calibration set of 25 samples and a validation set of 12 samples.Specifically,the GA was used to select the spectral subsets for each composition,which were then input into the PLSR model to derive the chemical concentration.The coefficient of determination(R2)values on the validation set for SiO2,Al2O3,Fe2O3,and the IOL were greater than 0.9.In addition,the effects of various spectral preprocessing techniques on the model accuracy were evaluated.We found that the spectral derivative treatment boosted the prediction accuracy of the GA-PLSR model.The improvement achieved with the second derivative was more pronounced than when using the first derivative.The quantitative model developed in this work has the potential to estimate the contents of similar weathering basalt products,and thus infer the degree of alteration and provide insights into paleoclimatic conditions.Moreover,the informative bands selected by the GA can serve as a guideline for designing spectral channels for the next generation of spectrometers. 展开更多
关键词 reflectance spectroscopy weathered basalts terrestrial analog quantitative retrieval MARS
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Low Complexity Hybrid Wideband Beamforming for Millimeter-Wave Massive MIMO-OFDM Systems
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作者 Mohammad Assaf Oleg G Ponomarev 《China Communications》 SCIE CSCD 2024年第12期39-48,共10页
In mmWave massive multiple-input multiple-output(MIMO)communication systems,the extension of low-complexity narrowband precoding schemes to be operated on wideband systems under frequency-selective channels remains an... In mmWave massive multiple-input multiple-output(MIMO)communication systems,the extension of low-complexity narrowband precoding schemes to be operated on wideband systems under frequency-selective channels remains an important challenge at the current time.This paper investigates a low complexity wideband hybrid precoding scheme for mmWave massive MIMO multicarrier systems under a single-user,fully-connected hybrid architecture.We show that the radio frequency(RF)precoding/combining vectors can be directly derived from the eigenvectors of the optimal fully-digital covariance matrix over all subcarriers in order to maximize the sum rate of spectral efficiency.We also suggest a new method that iteratively reduces the residual error between the covariance matrix and the sum of products of precoding matrices over all the subcarriers to improve the performance in the case where the number of RF chains is higher than the number of streams.The results of the simulation show that the proposed schemes’complexity is low compared to the present methods,and their performance can almost reach the upper bound achieved by the optimal full-baseband design. 展开更多
关键词 analog/digital precoding massive MIMO millimeter wave communication wideband hybrid
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Balloon-based exposed payload designed for astrobiological research in Earth’s near space
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作者 YanQiu Wang JianXun Shen +4 位作者 Chao Wang WeiNing Li GaoHong Wang Wei Lin YuanDa Jiang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第6期878-889,共12页
Earth’s near space,located in the region between 20 and 100 km above sea level,is characterized by extreme conditions,such as low temperature,low atmospheric pressure,harsh radiation,and extreme dryness.These conditi... Earth’s near space,located in the region between 20 and 100 km above sea level,is characterized by extreme conditions,such as low temperature,low atmospheric pressure,harsh radiation,and extreme dryness.These conditions are analogous to those found on the surface of Mars and in the atmosphere of Venus,making Earth’s near space a unique natural laboratory for astrobiological research.To address essential astrobiological questions,teams from the Chinese Academy of Sciences(CAS)have developed a scientific balloon platform,the CAS Balloon-Borne Astrobiology Platform(CAS-BAP),to study the effects of near space environmental conditions on the biology and survival strategies of representative organisms in this terrestrial analog.Here,we describe the versatile Biological Samples Exposure Payload(BIOSEP)loaded on the CAS-BAP with respect to its structure and function.The primary function of BIOSEP is to expose appropriate biological specimens to the harsh conditions of near space and subsequently return the exposed samples to laboratories for further analysis.Four successful flight missions in near space from 2019 to 2021 have demonstrated the high reliability and efficiency of the payload in communicating between hardware and software units,recording environmental data,exposing sample containers,protecting samples from external contamination,and recovering samples.Understanding the effects of Earth’s near space conditions on biological specimens will provide valuable insights into the survival strategies of organisms in extreme environments and the search for life beyond Earth.The development of BIOSEP and associated biological exposure experiments will enhance our understanding of the potential for life on Mars and the habitability of the atmospheric regions of other planets in the solar system and beyond. 展开更多
关键词 Earth’s near space biological sample exposure payload performance testing Mars analog ASTROBIOLOGY
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Experimental and computational optimization of Prussian blue analogues as high-performance cathodes for sodium-ion batteries:A review
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作者 Gwangeon Oh Junghoon Kim +4 位作者 Shivam Kansara Hyokyeong Kang Hun-Gi Jung Yang-Kook Sun Jang-Yeon Hwang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期627-662,I0015,共37页
In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte modifications.We integrated experimental data and density functional t... In this review,we discuss the electrochemical properties of Prussian blue(PB)for Na^(+)storage by combining structural engineering and electrolyte modifications.We integrated experimental data and density functional theory(DFT)in sodium-ion battery(SIB)research to refine the atomic arrangements and crystal lattices and introduce substitutions and dopants.These changes affect the lattice stability,intercalation,electronic and ionic conductivities,and electrochemical performance.We unraveled the intricate structure-electrochemical behavior relationship by combining experimental data with computational models,including first-principles calculations.This holistic approach identified techniques for optimizing PB and Prussian blue analog(PBA)structu ral properties for SIBs.We also discuss the tuning of electrolytes by systematically adjusting their composition,concentration,and additives using a combination of molecular dynamics(MD)simulations and DFT computations.Our review offers a comprehensive assessment of strategies for enhancing the electrochemical properties of PB and PBAs through structural engineering and electrolyte modifications,combining experimental insights with advanced computational simulations,and paving the way for next-generation energy storage systems. 展开更多
关键词 Prussian blue analogs(PBAs) Sodium ion batteries(SIBs) Structural engineering Electrolyte modifications Experiments Density functional theory(DFT)
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Paravertebral block's effect on analgesia and inflammation in advanced gastric cancer patients undergoing transarterial chemoembolization and microwave ablation
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作者 Ying-Fen Xiong Ben-Zhong Wei +2 位作者 Yu-Feng Wang Xiao-Feng Li Cong Liu 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第1期196-204,共9页
BACKGROUND Transarterial chemoembolization(TACE)combined with microwave ablation(MWA)is an effective treatment strategy for patients with advanced gastric cancer and liver metastasis.However,it may cause severe postop... BACKGROUND Transarterial chemoembolization(TACE)combined with microwave ablation(MWA)is an effective treatment strategy for patients with advanced gastric cancer and liver metastasis.However,it may cause severe postoperative pain and inflammatory responses.The paravertebral block(PVB)is a regional anesthetic technique that provides analgesia to the thoracic and abdominal regions.AIM To evaluate the effect of PVB on postoperative analgesia and inflammatory response in patients undergoing TACE combined with MWA for advanced gastric cancer and liver metastasis.METHODS Sixty patients were randomly divided into PVB and control groups.The PVB group received ultrasound-guided PVB with 0.375%ropivacaine preoperatively,whereas the control group received intravenous analgesia with sufentanil.The primary outcome was the visual analog scale(VAS)score for pain at 6 h,12 h,24 h,and 48 h after the procedure.Secondary outcomes were the dose of sufentanil used,incidence of adverse events,and levels of inflammatory markers(white blood cell count,neutrophil percentage,C-reactive protein,and procalcitonin)before and after the procedure.RESULTS The PVB group had significantly lower VAS scores at 6 h,12 h,24 h,and 48 h after the procedure compared with the control group(P<0.05).The PVB group also had a significantly lower consumption of sufentanil and a lower incidence of nausea,vomiting,and respiratory depression than did the control group(P<0.05).Compared with the control group,the PVB group had significantly lower levels of inflammatory markers 24 h and 48 h after the procedure(P<0.05).CONCLUSION PVB can effectively reduce postoperative pain and inflammatory responses and improve postoperative comfort and recovery in patients with advanced gastric cancer and liver metastasis treated with TACE combined with MWA. 展开更多
关键词 Transarterial chemoembolization Microwave ablation Paravertebral block Visual analog scale SUFENTANIL Inflammatory markers
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Clinical therapeutic effect of self-prescribed Sanhanchushi Tongbi on lumbar disc herniation
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作者 Cheng Yao Bin He +1 位作者 Jie Zhou Lin Xie 《World Journal of Clinical Cases》 SCIE 2024年第18期3444-3452,共9页
BACKGROUND Lumbar disc herniation(LDH)commonly occurs during spinal surgery;LDH is on the increase in younger patients and is classified as"paralysis"and"back pain."Sanhanchushi Tongbi(SPST)is a cu... BACKGROUND Lumbar disc herniation(LDH)commonly occurs during spinal surgery;LDH is on the increase in younger patients and is classified as"paralysis"and"back pain."Sanhanchushi Tongbi(SPST)is a customized prescription.It disperses cold,relieves pain,removes cold from the meridians and viscera,and treats neuropathic pain.However,few studies have investigated its mechanism of pain relief.AIM To observe the clinical therapeutic effects on LDH treated with self-prescribed SPST.METHODS A total of 211 patients with LDH syndrome were divided into two groups:107 patients in the control group were treated with conventional massage combined with traction,and 104 patients in the observation group were treated with a combination of the control regimen and self-prescribed oral SPST.The patients were treated for 4 wk.Indices of traditional Chinese medicine(TCM)syndrome score and serum inflammatory factor levels were measured.RESULTS After therapy,the TCM syndrome score in the observation group was significantly lower than that in the control group(P<0.05).The main symptoms,clinical signs,daily activities,and Japanese Orthopedic Association scores in the observation group were significantly higher than those in the control group after therapy(P<0.05).The levels of tumor necrosis factor-α,interleukin-6,and C-reactive protein were lower in the observation group than in the control group(P<0.05).In the observation group,superoxide dismutase levels were significantly higher,whereas malondialdehyde levels were significantly lower,compared with the control group(P<0.05).The overall efficacy rate in the observation group was 96.15%,which was substantially higher than that in the control group(88.79%;P<0.05).CONCLUSION Self-prescribed SPST can reduce the levels of inflammatory and pain-causing factors as well as lumbar pain in patients with LDH. 展开更多
关键词 Self-prescribed Sanhanchushi Tongbi Lumbar disc herniation Pain factors Visual analog scale Japanese Orthopedic Association scores Inflammatory factor
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Nullors, and Nullor Circuits;There Applications in Symbolic Circuit Analysis and Design
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作者 Reza Hashemian 《Applied Mathematics》 2024年第1期33-45,共13页
The objective in this presentation is to introduce some of the unique properties and applications of nullors in active circuit analysis and designs. The emphasis is to discuss the role nullors can play in symbolic rep... The objective in this presentation is to introduce some of the unique properties and applications of nullors in active circuit analysis and designs. The emphasis is to discuss the role nullors can play in symbolic representation of transfer functions. To show this we adopt the topological platform for the circuit analysis and use a recently developed Admittance Method (AM) to achieve the Sum of Tree Products (STP), replacing the determinant and cofactors of the Nodal Admittance Matrix (NAM) of the circuit. To construct a transfer function, we start with a given active circuit and convert all its controlled sources and I/O-ports to nullors. Now, with a solid nullor circuit (passive elements and nullors) we first eliminate the passive elements through AM operations. This produces the STPs. Second, the all-nullor circuit is then used to find the signs or the STPs. Finally, the transfer function (in symbolic, if chosen) is obtained from the ratio between the STPs. 展开更多
关键词 Admittance Method Analog Circuits Nullors Nullor Circuits Sum of Tree Products Transfer Functions
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An Adaptive Control Strategy for Energy Storage Interface Converter Based on Analogous Virtual Synchronous Generator
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作者 Feng Zhao Jinshuo Zhang +1 位作者 Xiaoqiang Chen Ying Wang 《Energy Engineering》 EI 2024年第2期339-358,共20页
In the DC microgrid,the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic power.To ... In the DC microgrid,the lack of inertia and damping in power electronic converters results in poor stability of DC bus voltage and low inertia of the DC microgrid during fluctuations in load and photovoltaic power.To address this issue,the application of a virtual synchronous generator(VSG)in grid-connected inverters control is referenced and proposes a control strategy called the analogous virtual synchronous generator(AVSG)control strategy for the interface DC/DC converter of the battery in the microgrid.Besides,a flexible parameter adaptive control method is introduced to further enhance the inertial behavior of the AVSG control.Firstly,a theoretical analysis is conducted on the various components of the DC microgrid,the structure of analogous virtual synchronous generator,and the control structure’s main parameters related to the DC microgrid’s inertial behavior.Secondly,the voltage change rate tracking coefficient is introduced to adjust the change of the virtual capacitance and damping coefficient flexibility,which further strengthens the inertia trend of the DC microgrid.Additionally,a small-signal modeling approach is used to analyze the approximate range of the AVSG’s main parameters ensuring system stability.Finally,conduct a simulation analysis by building the model of the DC microgrid system with photovoltaic(PV)and battery energy storage(BES)in MATLAB/Simulink.Simulation results from different scenarios have verified that the AVSG control introduces fixed inertia and damping into the droop control of the battery,resulting in a certain level of inertia enhancement.Furthermore,the additional adaptive control strategy built upon the AVSG control provides better and flexible inertial support for the DC microgrid,further enhances the stability of the DC bus voltage,and has a more positive impact on the battery performance. 展开更多
关键词 Adaptive control analogous virtual synchronous generator DC/DC converter inertia of DC microgrid DC microgrid with PV and BES BATTERY DC bus voltage
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The Analogy between the Immune System and Human Life
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作者 Gassem Gohal 《Open Journal of Immunology》 2024年第3期47-59,共13页
The immune system operates as a complex organization with distinct roles and functions. Excitingly we recognized the similarities between the cellular dynamics of the immune system and our lives, activities, and behav... The immune system operates as a complex organization with distinct roles and functions. Excitingly we recognized the similarities between the cellular dynamics of the immune system and our lives, activities, and behaviors. Observing the immune system can guide how to respond to various daily situations, including when to react, tolerate, or ignore. Recognizing this analogy between our lives and the immune system should motivate us to adopt a wisdom-based approach when investigating the mechanisms and future discoveries related to this system and to deepen our understanding of this complex system with newfound respect. In this context, the present review examines several integral biological processes of the immune system by drawing parallels between them and human life, activities, and behaviors to learn how we must behave based on the insights offered by this complex organization. The literature search was conducted in international databases such as PubMed/MEDLINE and Google Scholar search engine using English equivalent keywords from 1998 up to April 2023. The search strategy used the following subject heading terms: Immune system, analogy, human life, cellular dynamics, memory, tolerance, and ignorance. In conclusion, the immune system is a complex organization comprising various cells interacting within specific sites and networks, communicating, drawing experiences, and learning how to tolerate certain conditions that make it share certain similarities with human life. 展开更多
关键词 Immune System ANALOGY MEMORY TOLERANCE IGNORANCE
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Embracing Ethnic Harmony In Xinjiang
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作者 Antony Hardi 《China Report ASEAN》 2024年第10期42-42,共1页
"All ethnic groups remain closely united like the seeds of a pomegranate that stick together,"goes a saying that deeply resonated with me as an Indonesian when I first heard it in China's Xinjiang Uygur ... "All ethnic groups remain closely united like the seeds of a pomegranate that stick together,"goes a saying that deeply resonated with me as an Indonesian when I first heard it in China's Xinjiang Uygur Autonomous Region.The analogy was cemented even deeper in my brain when I learned that Xinjiang is known as a"Homeland of Pomegranates." 展开更多
关键词 XINJIANG ANALOGY CEMENTED
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Biological Evaluation of a Novel 2’-Fluoro Derivative 5-Azacytidine as a Potent DNA Methyltransferase Inhibitor
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作者 Elena Kalinichenko Tatyana Bozhok +1 位作者 Roman Zilberman Alesya Panibrat 《Pharmacology & Pharmacy》 2024年第11期388-402,共15页
Background: DNA methyltransferases (DNMTs) are key epigenetic regulatory enzymes involved in the expression of many genes and are considered as an attractive target for cancer treatment, especially hematological malig... Background: DNA methyltransferases (DNMTs) are key epigenetic regulatory enzymes involved in the expression of many genes and are considered as an attractive target for cancer treatment, especially hematological malignancies. Therefore, promising DNMT inhibitors characterized by low toxicity, target activity and high selectivity are crucial for the development of new cancer therapy and research on the inhibitory mechanism. We had previously demonstrated that the novel 2’-fluoro-2’-deoxy-arabinofuranosyl 5-azacytosine nucleoside (2’F-araAC) showed high antiproliferative activity in vitro and increased hydrolytic stability compared to the known agents like azacitidine and decitabine. Objective: The objective of the present study was to investigate the effect of novel 2’F-araAC as potent anti-leukemia agent and DNMTs inhibitor on nuclear extract of the HCT-116 human colorectal cell line and P388 and L1210 mouse leukemia cell lines. Methods: The DNMTs activity was evaluated using the fluorometric DNMT Activity Quantification Kit (Abcam) and were reported as the percentage of control. Nuclear proteins were extracted from HCT-116 cell line using the Nuclear Extraction Kit (Abcam). To explore the mechanism of anti-leukemic activity of 2’F-araAC, cell cycle and apoptosis analyses were performed on P388 and L1210 cell lines. Results: It has been shown that the DNMTs activity was significantly reduced at 1 and 10 µM of 2’F-araAC compared to controls. Moreover, 2’F-araAC can induce G2/M cell cycle arrest and apoptosis in P388 and L1210 mouse leukemia cell lines as shown by flow cytometry method. Apoptosis was 54.53% and 43.35% for 2’F-araAC vs. 2.88% and 5.25% for the control P388 and L1210 cell lines, respectively. Conclusions: Thus, our study presents a new and promising compound to further develop new epigenetic regulators to be used as antitumor agents. 展开更多
关键词 Drug Discovery DECITABINE 2’-Fluorodeoxy-Arabino Analog DNA Methyltransferase Enzyme Inhibition Cell Cycle Apoptosis
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Habitable Land Will Soon Become the World’s Scarcest Resource: Why Appalachia Should Choose Climate Change Havens over Millionaire Estates and Golf Courses
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作者 Elizabeth C. Hirschman Devonte Booth +5 位作者 Tzu-Wei Huang Kamryn Livingston Kobe McReynolds Rachel Six Logan Smith Olivia Toomer 《Journal of Environmental Protection》 2024年第6期716-730,共15页
This research advocates for the construction of Climate Change Haven Communities across the Appalachian Region. The proposed development plan can be extended to the northern tier states across the US and also to the n... This research advocates for the construction of Climate Change Haven Communities across the Appalachian Region. The proposed development plan can be extended to the northern tier states across the US and also to the northern and mountainous regions of Europe and Asia. We present an analogy to the earlier climate change period of the Last Glacial Maximum/“Ice Age” in which these same northern regions of the planet were covered in ice sheets making them uninhabitable for most humans and many plant and animal species. In some significant ways, the Ice Age scenario can be a reverse-model for our current climate crisis. We also advocate strongly for the prevention of upscale real estate development projects in these same regions of the globe, as these will foreclose the possibility of safely sheltering the millions of persons who will be displaced by climate change over the next 5 to 10 years. 展开更多
关键词 Climate Change APPALACHIA Habitable Land Climate Change Haven Communities Two-Caste Economic System Migration Ice Age Analogies
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Investigation on Analog and Digital Modulations Recognition Using Machine Learning Algorithms
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作者 Jean Ndoumbe Ivan Basile Kabeina +1 位作者 Gaelle Patricia Talotsing Soubiel-Noël Nkomo Biloo 《World Journal of Engineering and Technology》 2024年第4期867-884,共18页
In the field of radiocommunication, modulation type identification is one of the most important characteristics in signal processing. This study aims to implement a modulation recognition system on two approaches to m... In the field of radiocommunication, modulation type identification is one of the most important characteristics in signal processing. This study aims to implement a modulation recognition system on two approaches to machine learning techniques, the K-Nearest Neighbors (KNN) and Artificial Neural Networks (ANN). From a statistical and spectral analysis of signals, nine key differentiation features are extracted and used as input vectors for each trained model. The feature extraction is performed by using the Hilbert transform, the forward and inverse Fourier transforms. The experiments with the AMC Master dataset classify ten (10) types of analog and digital modulations. AM_DSB_FC, AM_DSB_SC, AM_USB, AM_LSB, FM, MPSK, 2PSK, MASK, 2ASK, MQAM are put forward in this article. For the simulation of the chosen model, signals are polluted by the Additive White Gaussian Noise (AWGN). The simulation results show that the best identification rate is the MLP neuronal method with 90.5% of accuracy after 10 dB signal-to-noise ratio value, with a shift of more than 15% from the k-nearest neighbors’ algorithm. 展开更多
关键词 Automatic Recognition Artificial Neural Networks K-Nearest Neighbors Machine Learning Analog Modulations Digital Modulations
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