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Utility of plasma D-dimer for diagnosis of venous thromboembolism after hepatectomy
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作者 Taiichiro Miyake Hiroaki Yanagimoto +16 位作者 Daisuke Tsugawa Masayuki Akita Riki Asakura Keisuke Arai Toshihiko Yoshida Shinichi So Jun Ishida Takeshi Urade Yoshihide Nanno Kenji Fukushima Hidetoshi Gon Shohei Komatsu Sadaki Asari Hirochika Toyama Masahiro Kido Tetsuo Ajiki Takumi Fukumoto 《World Journal of Clinical Cases》 SCIE 2024年第2期276-284,共9页
BACKGROUND Venous thromboembolism(VTE)is a potentially fatal complication of hepatectomy.The use of postoperative prophylactic anticoagulation in patients who have undergone hepatectomy is controversial because of the... BACKGROUND Venous thromboembolism(VTE)is a potentially fatal complication of hepatectomy.The use of postoperative prophylactic anticoagulation in patients who have undergone hepatectomy is controversial because of the risk of postoperative bleeding.Therefore,we hypothesized that monitoring plasma D-dimer could be useful in the early diagnosis of VTE after hepatectomy.AIM To evaluate the utility of monitoring plasma D-dimer levels in the early diagnosis of VTE after hepatectomy.METHODS The medical records of patients who underwent hepatectomy at our institution between January 2017 and December 2020 were retrospectively analyzed.Patients were divided into two groups according to whether or not they developed VTE after hepatectomy,as diagnosed by contrast-enhanced computed tomography and/or ultrasonography of the lower extremities.Clinicopathological factors,including demographic data and perioperative D-dimer values,were compared between the two groups.Receiver operating characteristic curve analysis was performed to determine the D-dimer cutoff value.Univariate and multivariate analyses were performed using logistic regression analysis to identify significant predictors.RESULTS In total,234 patients who underwent hepatectomy were,of whom(5.6%)were diagnosed with VTE following hepatectomy.A comparison between the two groups showed significant differences in operative time(529 vs 403 min,P=0.0274)and blood loss(530 vs 138 mL,P=0.0067).The D-dimer levels on postoperative days(POD)1,3,5,7 were significantly higher in the VTE group than in the non-VTE group.In the multivariate analysis,intraoperative blood loss of>275 mL[odds ratio(OR)=5.32,95%confidence interval(CI):1.05-27.0,P=0.044]and plasma D-dimer levels on POD 5≥21μg/mL(OR=10.1,95%CI:2.04-50.1,P=0.0046)were independent risk factors for VTE after hepatectomy.CONCLUSION Monitoring of plasma D-dimer levels after hepatectomy is useful for early diagnosis of VTE and may avoid routine prophylactic anticoagulation in the postoperative period. 展开更多
关键词 HEPATECTOMY Malignant tumor Postoperative complication d-dimer Early diagnosis Venous thromboembolism
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Estimation and Assessment of Plasma D-Dimer Levels in HIV Patients 被引量:1
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作者 Wafa Hamid Haroun Himmat Nasr Eldeen Ali Mohammed Gaufri 《Journal of Biosciences and Medicines》 2016年第10期1-5,共6页
Background: The elevation of plasma D-dimer levels is fully described and associated with the increase of the mortality of patients with HIV. The present study was aimed to estimate and assess the plasma D-dimer level... Background: The elevation of plasma D-dimer levels is fully described and associated with the increase of the mortality of patients with HIV. The present study was aimed to estimate and assess the plasma D-dimer levels in HIV patient. Material and Methods: A case control study done in May 2015. A total of 100 subjects were enrolled in this study;50 were patients professionally diagnosed by HIV;25 (50%) were males and 25 (50%) were females;their mean age is 35 years. Further 50 normal healthy individuals as normal control group: their gender and age were matched with patient groups. The platelets poor plasma (PPP) was immediately prepared from citrated blood, then the plasma D-dimer level was measured using (MISPA-i<sub>2</sub> Reagent) Switzerland. Data were analyzed using statistical packing for social sciences program (SPSS) 20. Results: The D-dimer levels was significantly higher in patient with HIV compared with the normal healthy control group (Mean and STD 502.2 ± 287.8 vs 251.8 ± 152.7 P. value 0.01). Conclusion: The D-dimer level was significantly higher in patient with HIV compared with those in normal healthy control group. 展开更多
关键词 HIV AIDS d-dimer SUDAN
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Plasma D-dimer level in early and late-onset neonatal sepsis 被引量:2
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作者 Mohammed Al-Biltagi Ehab M Hantash +3 位作者 Mohammed Ramadan El-Shanshory Enayat Aly Badr Mohamed Zahra Manar Hany Anwar 《World Journal of Critical Care Medicine》 2022年第3期139-148,共10页
BACKGROUND Neonatal sepsis is a life-threatening disease.Early diagnosis is essential,but no single marker of infection has been identified.Sepsis activates a coagulation cascade with simultaneous production of the D-... BACKGROUND Neonatal sepsis is a life-threatening disease.Early diagnosis is essential,but no single marker of infection has been identified.Sepsis activates a coagulation cascade with simultaneous production of the D-dimers due to lysis of fibrin.Ddimer test reflects the activation of the coagulation system.AIM To assess the D-dimer plasma level,elaborating its clinicopathological value in neonates with early-onset and late-onset neonatal sepsis.METHODS The study was a prospective cross-sectional study that included ninety neonates;divided into three groups:Group I:Early-onset sepsis(EOS);Group II:Late-onset sepsis(LOS);and GroupⅢ:Control group.We diagnosed neonatal sepsis according to our protocol.C-reactive protein(CRP)and D-dimer assays were compared between EOS and LOS and correlated to the causative microbiological agents.RESULTS D-dimer was significantly higher in septic groups with a considerably higher number of cases with positive D-dimer.Neonates with LOS had substantially higher levels of D-dimer than EOS,with no significant differences in CRP.Neonates with LOS had a significantly longer hospitalization duration and higher gram-negative bacteriemia and mortality rates than EOS(P<0.01).Gramnegative bacteria have the highest D-dimer levels(Acinetobacter,Klebsiella,and Pseudomonas)and CRP(Serratia,Klebsiella,and Pseudomonas);while gram-positive sepsis was associated with relatively lower levels.D-dimer had a significant negative correlation with hemoglobin level and platelet count;and a significant positive correlation with CRP,hospitalization duration,and mortality rates.The best-suggested cut-off point for D-dimer in neonatal sepsis was 0.75 mg/L,giving a sensitivity of 72.7%and specificity of 86.7%.The D-dimer assay has specificity and sensitivity comparable to CRP in the current study.CONCLUSION The current study revealed a significant diagnostic value for D-dimer in neonatal sepsis.D-dimer can be used as an adjunct to other sepsis markers to increase the sensitivity and specificity of diagnosing neonatal sepsis. 展开更多
关键词 Early-onset neonatal sepsis Late-onset neonatal sepsis C-reactive protein d-dimer
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Final results of the first phase of the PROTO-SPHERA experiment: obtainment of the full current stable screw pinch and first evidences of the jet + torus combined plasma configuration
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作者 Paolo MICOZZI Franco ALLADIO +21 位作者 Alessandro MANCUSO Vincenzo ZANZA Gerarda APRUZZESE Francesca BOMBARDA Luca BONCAGNI Paolo BURATTI Francesco FILIPPI Giuseppe GALATOLA TEKA Francesco GIAMMANCO Edmondo GIOVANNOZZI Andrea GROSSO Matteo IAFRATI Alessandro LAMPASI Violeta LAZIC Simone MAGAGNINO Simone MANNORI Paolo MARSILI Valerio PIERGOTTI Giuliano ROCCHI Alessandro SIBIO Benedetto TILIA Onofrio TUDISCO 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期31-43,共13页
In astrophysics, the boundary conditions for plasma phenomena are provided by nature and the astronomer faces the problem of understanding them from a variety of observations [Hester J J et al 1996 Astrophys. J. 456 2... In astrophysics, the boundary conditions for plasma phenomena are provided by nature and the astronomer faces the problem of understanding them from a variety of observations [Hester J J et al 1996 Astrophys. J. 456 225], on the other hand, in laboratory plasma experiments the electromagnetic boundary conditions become a major problem in the set-up of the machine that produces the plasma, an issue that has to be investigated step by step and to be modified and adapted with great patience, in particular in the case of an innovative plasma confinement experiment. The PROTO-SPHERA machine [Alladio F et al 2006 Nucl. Fusion 46 S613] is a magnetic confinement experiment, that emulates in the laboratory the jet + torus plasma configurations often observed in astrophysics: an inner magnetized jet of plasma centered on the(approximate) axis of symmetry and surrounded by a magnetized plasma torus orthogonal to this jet. The PROTO-SPHERA plasma is simply connected, i.e., no metal current conducting rod is linked to the plasma torus, while instead it is the inner magnetized plasma jet(in the following always called the plasma centerpost) that is linked to the torus. It is mandatory that no spurious plasma current path modifies the optimal shape of the plasma centerpost. Moreover, as the plasma torus is produced and sustained, in absence of any applied inductive electric field, by the inner plasma centerpost through magnetic reconnections [Taylor J B and Turner M F 1989 Nucl.Fusion 29 219], it is required as well that spurious current paths do not surround the torus on its outboard, in order not to lower the efficiency of the magnetic reconnections that maintain the plasma torus at the expense of the plasma centerpost. Boundary conditions have been corrected,up to the point that the first sustainment in steady state has been achieved for the combined plasma. 展开更多
关键词 laboratory plasmas magnetic confinement astrophysical plasmas
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Wave field structure and power coupling features of blue-core helicon plasma driven by various antenna geometries and frequencies
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作者 王超 刘佳 +3 位作者 苌磊 卢凌峰 张世杰 周帆涛 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期480-487,共8页
This paper deals with wave propagation and power coupling in blue-core helicon plasma driven by various antennas and frequencies.It is found that compared to non-blue-core mode,for blue-core mode,the wave can propagat... This paper deals with wave propagation and power coupling in blue-core helicon plasma driven by various antennas and frequencies.It is found that compared to non-blue-core mode,for blue-core mode,the wave can propagate in the core region,and it decays sharply outside the core.The power absorption is lower and steeper in radius for blue-core mode.Regarding the effects of antenna geometry for blue-core mode,it shows that half helix antenna yields the strongest wave field and power absorption,while loop antenna yields the lowest.Moreover,near axis,for antennas with m=+1,the wave field increases with axial distance.In the core region,the wave number approaches to a saturation value at much lower frequency for non-blue-core mode compared to blue-core mode.The total loading resistance is much lower for blue-core mode.These findings are valuable to understanding the physics of blue-core helicon discharge and optimizing the experimental performance of blue-core helicon plasma sources for applications such as space propulsion and material treatment. 展开更多
关键词 helicon plasma helicon wave helicon discharge radio frequency plasma source
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Numerical studies for plasmas of a linear plasma device HIT-PSI with geometry modified SOLPS-ITER
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作者 王敏 聂秋月 +2 位作者 黄韬 王晓钢 张彦杰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期503-508,共6页
The HIT-PSI is a linear plasma device built for physically simulating the high heat flux environment of future reactor divertors to test/develop advanced target plate materials.In this study,the geometry-modified SOLP... The HIT-PSI is a linear plasma device built for physically simulating the high heat flux environment of future reactor divertors to test/develop advanced target plate materials.In this study,the geometry-modified SOLPS-ITER program is employed to examine the effects of the magnetic field strength and neutral pressure in the device on the heat flux experienced by the target plate of the HIT-PSI device.The findings of the numerical simulation indicate a positive correlation between the magnetic field strength and the heat flux density.Conversely,there is a negative correlation observed between the heat flux density and the neutral pressure.When the magnetic field strength at the axis exceeds 1 tesla and the neutral pressure falls below 10 Pa,the HIT-PSI has the capability to attain a heat flux of 10 MW·m-2 at the target plate.The simulation results offer a valuable point of reference for subsequent experiments at HIT-PSI. 展开更多
关键词 HIT-PSI heat flux linear plasma SOLPS-ITER device
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Airfoil friction drag reduction based on grid-type and super-dense array plasma actuators
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作者 方子淇 宗豪华 +2 位作者 吴云 梁华 苏志 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期94-103,共10页
To improve the cruise flight performance of aircraft, two new configurations of plasma actuators(grid-type and super-dense array) were investigated to reduce the turbulent skin friction drag of a low-speed airfoil. Th... To improve the cruise flight performance of aircraft, two new configurations of plasma actuators(grid-type and super-dense array) were investigated to reduce the turbulent skin friction drag of a low-speed airfoil. The induced jet characteristics of the two actuators in quiescent air were diagnosed with high-speed particle image velocimetry(PIV), and their drag reduction efficiencies were examined under different operating conditions in a wind tunnel. The results showed that the grid-type plasma actuator was capable of producing a wall-normal jet array(peak magnitude: 1.07 m/s) similar to that generated in a micro-blowing technique, while the superdense array plasma actuator created a wavy wall-parallel jet(magnitude: 0.94 m/s) due to the discrete spanwise electrostatic forces. Under a comparable electrical power consumption level,the super-dense array plasma actuator array significantly outperformed the grid-type configuration,reducing the total airfoil friction drag by approximately 22% at a free-stream velocity of 20 m/s.The magnitude of drag reduction was proportional to the dimensionless jet velocity ratio(r), and a threshold r = 0.014 existed under which little impact on airfoil drag could be discerned. 展开更多
关键词 plasma actuator flow control drag reduction AIRFOIL
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Exercised blood plasma promotes hippocampal neurogenesis in the Alzheimer's disease rat brain
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作者 Cecilie Skarstad Norevik Aleksi M.Huuha +10 位作者 Ragnhild N.RФsbjФrgen Linda Hildegard Bergersen Kamilla Jacobsen Rodrigo Miguel-dos-Santos Liv Ryan Belma Skender Jose Bianco N.Moreira Asgeir Kobro-Flatmoen Menno P.Witter Nathan Scrimgeour Atefe R.Tari 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期245-255,共11页
Background:Exercise training promotes brain plasticity and is associated with protection against cognitive impairment and Alzheimer’s disease(AD).These beneficial effects may be partly mediated by blood-borne factors... Background:Exercise training promotes brain plasticity and is associated with protection against cognitive impairment and Alzheimer’s disease(AD).These beneficial effects may be partly mediated by blood-borne factors.Here we used an in vitro model of AD to investigate effects of blood plasma from exercise-trained donors on neuronal viability,and an in vivo rat model of AD to test whether such plasma impacts cognitive function,amyloid pathology,and neurogenesis.Methods:Mouse hippocampal neuronal cells were exposed to AD-like stress using amyloid-βand treated with plasma collected from human male donors 3 h after a single bout of high-intensity exercise.For in vivo studies,blood was collected from exercise-trained young male Wistar rats(high-intensity intervals 5 days/week for 6 weeks).Transgenic AD rats(McGill-R-Thyl-APP)were inj ected 5 times/fortnight for 6 weeks at2 months or 5 months of age with either(a)plasma from the exercise-trained rats,(b)plasma from sedentary rats,or(c)saline.Cognitive function,amyloid plaque pathology,and neurogenesis were assessed.The plasma used for the treatment was analyzed for 23 cytokines.Results:Plasma from exercised donors enhanced cell viability by 44.1%(p=0.032)and reduced atrophy by 50.0%(p<0.001)in amyloid-β-treated cells.In vivo exercised plasma treatment did not alter cognitive function or amyloid plaque pathology but did increase hippocampal neurogenesis by~3 fold,regardless of pathological stage,when compared to saline-treated rats.Concentrations of 7 cytokines were significantly reduced in exercised plasma compared to sedentary plasma.Conclusion:Our proof-of-concept study demonstrates that plasma from exercise-trained donors can protect neuronal cells in culture and promote adult hippocampal neurogenesis in the AD rat brain.This effect may be partly due to reduced pro-inflammatory signaling molecules in exercised plasma. 展开更多
关键词 CYTOKINES High-intensity interval training Inflammation NEURONS plasma transfusion
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Laser-induced plasma formation in water with up to 400 mJ double-pulse LIBS
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作者 Marion HENKEL Michelle SIEMENS +4 位作者 Ralf METHLING Benjamin EMDE Jörg HERMSDORF Steffen FRANKE Diego GONZALEZ 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期93-100,共8页
Double-pulse LIBS is a promising technique for deep-sea applications.LIBS measurements in shallow water with up to 400 mJ each pulse were done to select laser parameters which promote optimized spectral line emission ... Double-pulse LIBS is a promising technique for deep-sea applications.LIBS measurements in shallow water with up to 400 mJ each pulse were done to select laser parameters which promote optimized spectral line emission from plasma even at elevated pressures,where line broadening until loss of most of the spectral information can occur.Optical emission spectroscopy,using a Czerny-Turner spectrometer,has been applied to investigate the dependence of the emitted radiation on laser parameters and hydrostatic pressure.It has been found,that higher laser pulse energies,especially with short pulse delay as required in high water pressure,can also have an adverse effect on the measured spectrum. 展开更多
关键词 double-pulse LIBS UNDERWATER plasma formation emission spectrosocpy
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Plasma potential measurements using an emissive probe made of oxide cathode
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作者 李建泉 马海杰 陆文琪 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期571-577,共7页
A novel emissive probe consisting of an oxide cathode coating is developed to achieve a low operating temperature and long service life.The properties of the novel emissive probe are investigated in detail,in comparis... A novel emissive probe consisting of an oxide cathode coating is developed to achieve a low operating temperature and long service life.The properties of the novel emissive probe are investigated in detail,in comparison with a traditional tungsten emissive probe,including the operating temperature,the electron emission capability and the plasma potential measurement.Studies of the operating temperature and electron emission capability show that the tungsten emissive probe usually works at a temperature of 1800 K-2200 K while the oxide cathode emissive probe can function at about 1200 K-1400 K.In addition,plasma potential measurements using the oxide cathode emissive probe with different techniques have been accomplished in microwave electron cyclotron resonance plasmas with different discharge powers.It is found that a reliable plasma potential can be obtained using the improved inflection point method and the hot probe with zero emission limit method,while the floating point method is invalid for the oxide cathode emissive probe. 展开更多
关键词 emissive probe oxide cathode plasma potential filament temperature
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Effect of ion stress on properties of magnetized plasma sheath
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作者 陈龙 崔作君 +4 位作者 高维富 段萍 阚子晨 檀聪琦 陈俊宇 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第2期1-12,共12页
In the plasma sheath, there is a significant gradient in ion velocity, resulting in strong stress on ions treated as a fluid. This aspect has often been neglected in previous sheath studies. This study is based on the... In the plasma sheath, there is a significant gradient in ion velocity, resulting in strong stress on ions treated as a fluid. This aspect has often been neglected in previous sheath studies. This study is based on the Braginskii plasma transport theory and establishes a 1D3V sheath fluid model that takes into account the ion stress effect. Under the assumption that ions undergo both electric and diamagnetic drift in the presheath region, self-consistent boundary conditions,including the ion Bohm velocity, are derived based on the property of the Sagdeev pseudopotential.Furthermore, assuming that the electron velocity at the wall follows a truncated Maxwell distribution, the wall floating potential is calculated, leading to a more accurate sheath thickness estimation. The results show that ion stress significantly reduces the sheath thickness, enhances ion Bohm velocity, wall floating potential, and ion flux at the wall. It hinders the acceleration of ions within the sheath, leading to notable alterations in the particle density profiles within the sheath. Further research indicates that in ion stress, bulk viscous stress has the greatest impact on sheath properties. 展开更多
关键词 magnetized plasma sheath ion stress Bohm criterion
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Spark Plasma Sintering of Mg-based Alloys:Microstructure,Mechanical Properties,Corrosion Behavior,and Tribological Performance
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作者 Alessandro M.Ralls Mohammadreza Daroonparvar Pradeep L.Menezes 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第2期405-442,共38页
Within the past ten years,spark plasma sintering(SPS)has become an increasingly popular process for Mg manufacturing.In the SPS process,interparticle diffusion of compressed particles is rapidly achieved due to the co... Within the past ten years,spark plasma sintering(SPS)has become an increasingly popular process for Mg manufacturing.In the SPS process,interparticle diffusion of compressed particles is rapidly achieved due to the concept of Joule heating.Compared to traditional and additive manufacturing(AM)techniques,SPS gives unique control of the structural and microstructural features of Mg components.By doing so,their mechanical,tribological,and corrosion properties can be tailored.Although great advancements in this field have been made,these pieces of knowledge are scattered and have not been contextualized into a single work.The motivation of this work is to address this scientific gap and to provide a groundwork for understanding the basics of SPS manufacturing for Mg.To do so,the existing body of SPS Mg literature was first surveyed,with a focus on their structural formation and degradation mechanisms.It was found that successful Mg SPS fabrication highly depended on the processing temperature,particle size,and particle crystallinity.The addition of metal and ceramic composites also affected their microstructural features due to the Zener pinning effect.In degradative environments,their performance depends on their structural features and whether they have secondary phased composites.In industrial applications,SPS'd Mg was found to have great potential in biomedical,hydrogen storage,battery,automotive,and recycling sectors.The prospects to advance the field include using Mg as a doping agent for crystallite size refinement and using bulk metallic Mg-based glass powders for amorphous SPS components.Despite these findings,the interactions of multi-composites on the processing-structure-property relationships of SPS Mg is not well understood.In total,this work will provide a useful direction in the SPS field and serve as a milestone for future Mg-based SPS manufacturing. 展开更多
关键词 Spark plasma sintering Magnesium alloys NANOCRYSTALLINE TRIBOLOGY Mechanical properties Corrosion
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Plasma nitrogen fixation system with dual-loop enhancement for improved energy efficiency and its efficacy for lettuce cultivation
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作者 韩泽阳 张梦雪 +8 位作者 张頔 何欣 井天军 葛知轩 李玉鸽 朱童 任云鸿 仲崇山 季方 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期82-92,共11页
Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this ... Plasma nitrogen fixation(PNF)has been emerging as a promising technology for greenhouse gasfree and renewable energy-based agriculture.Yet,most PNF studies seldom address practical application-specific issues.In this work,we present the development of a compact and automatic PNF system for on-site agricultural applications.The system utilized a gliding-arc discharge as the plasma source and employed a dual-loop design to generate NO_(x)from air and water under atmospheric conditions.Experimental results showed that the system with a dualloop design performs well in terms of energy costs and production rates.Optimal operational parameters for the system were determined through experimentation,resulting in an energy cost of 13.9 MJ mol^(-1)and an energy efficiency of 16 g kWh^(-1)for NO_(3)^(-)production,respectively.Moreover,the concentration of exhausted NO_(x)was below the emission standards.Soilless lettuce cultivation experiments demonstrated that NO_(x)^(-)produced by the PNF system could serve as liquid nitrate nitrogen fertilizer.Overall,our work demonstrates the potential of the developed PNF system for on-site application in the production of green-leaf vegetables. 展开更多
关键词 plasma nitrogen fixation gliding arc soilless cultivation LETTUCE
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Transition from a filamentary mode to a diffuse one with varying distance from needle to stream of an argon plasma jet
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作者 许慧敏 高敬格 +3 位作者 贾鹏英 冉俊霞 陈俊宇 李金懋 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期539-544,共6页
Plasma jet has extensive application potentials in various fields, which normally operates in a diffuse mode when helium is used as the working gas. However, when less expensive argon is used, the plasma jet often ope... Plasma jet has extensive application potentials in various fields, which normally operates in a diffuse mode when helium is used as the working gas. However, when less expensive argon is used, the plasma jet often operates in a filamentary mode. Compared to the filamentary mode, the diffuse mode is more desirable for applications. Hence, many efforts have been exerted to accomplish the diffuse mode of the argon plasma jet. In this paper, a novel single-needle argon plasma jet is developed to obtain the diffuse mode. It is found that the plasma jet operates in the filamentary mode when the distance from the needle tip to the central line of the argon stream(d) is short. It transits to the diffuse mode with increasing d. For the diffuse mode, there is always one discharge pulse per voltage cycle, which initiates at the rising edge of the positive voltage. For comparison, the number of discharge pulse increases with an increase in the peak voltage for the filamentary mode. Fast photography reveals that the plasma plume in the filamentary mode results from a guided positive streamer,which propagates in the argon stream. However, the plume in the diffuse mode originates from a branched streamer, which propagates in the interfacial layer between the argon stream and the surrounding air. By optical emission spectroscopy,plasma parameters are investigated for the two discharge modes, which show a similar trend with increasing d. The diffuse mode has lower electron temperature, electron density, vibrational temperature, and gas temperature compared to the filamentary mode. 展开更多
关键词 plasma jet diffuse mode filamentary mode optical emission spectroscopy
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Fabrication of YAG:Ce^(3+) and YAG:Ce^(3+),Sc^(3+) Phosphors by Spark Plasma Sintering Technique
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作者 周卫新 娄朝刚 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第2期255-260,共6页
In this study,a single-doped phosphors yttrium aluminum garnet(Y_(3)Al_(5)O_(12),YAG):Ce^(3+),single-doped YAG:Sc^(3+),and double-doped phosphors YAG:Ce^(3+),Sc^(3+) were prepared by spark plasma sintering(SPS)(lower ... In this study,a single-doped phosphors yttrium aluminum garnet(Y_(3)Al_(5)O_(12),YAG):Ce^(3+),single-doped YAG:Sc^(3+),and double-doped phosphors YAG:Ce^(3+),Sc^(3+) were prepared by spark plasma sintering(SPS)(lower than 1 200℃).The characteristics of synthesized phosphors were determined using scanning electron microscopy(SEM),X-ray diffraction(XRD),and fluorescence spectroscopy.During SPS,the lattice structure of YAG was maintained by the added Ce^(3+) and Sc^(3+).The emission wavelength of YAG:Ce^(3+) prepared from SPS(425-700 nm) was wider compared to that of YAG:Ce^(3+) prepared from high-temperature solid-state reaction(HSSR)(500-700 nm).The incorporation of low-dose Sc^(3+) in YAG:Ce^(3+) moved the emission peak towards the short wavelength. 展开更多
关键词 high-temperature solid-state reaction spark plasma sintering yttrium aluminum garnet PHOSPHORS
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Efficacy of intraovarian autologous platelet-rich plasma administration in women with low ovarian reserve: A systematic review and meta-analysis
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作者 Yasmin Sabina Sa’diah Agung Dewanto Lukman A Chandra 《Asian pacific Journal of Reproduction》 CAS 2024年第2期60-67,共8页
Objective:To conduct a systematic examination and meta-analysis of the most reliable data from experimental studies evaluating the efficacy of autologous platelet-rich plasma(PRP)on low ovarian reserve.Methods:A compr... Objective:To conduct a systematic examination and meta-analysis of the most reliable data from experimental studies evaluating the efficacy of autologous platelet-rich plasma(PRP)on low ovarian reserve.Methods:A comprehensive search was performed utilizing pertinent search terms across electronic databases,including PubMed,Cochrane,and Google Scholar.We included studies that assigned infertile women with low ovarian reserve in experimental studies.Ovarian reserve parameters were measured before and after PRP injection into ovaries.The data of each study was retrieved and subsequently compiled.Results:Of 301 articles collected and reviewed,six studies were finally included in the meta-analysis.Following PRP injection,infertile women showed a non-significant increase in anti-Mullerian hormone(AMH)level(MD=0.10;95%CI-0.04,0.23),a significant increase in antral follicular count(AFC)(MD=1.88;95%CI 0.47,3.29),and a non-significant reduction in follicle-stimulating hormone(FSH)level(MD=-0.22;95%CI-8.32,7.87).Conclusions:Autologous PRP may increase AFC,but not AMH.Although it is found beneficial in enhancing ovarian reserve(AFC),further research with strong evidence is still required. 展开更多
关键词 Platelet-rich plasma Low ovarian reserve Ovarian rejuvenation
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Different bactericidal abilities of plasma-activated saline with various reactive species prepared by surface plasma-activated air and plasma jet combinations
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作者 贾怡康 李甜会 +5 位作者 张瑞 赵鹏瑜 王子丰 陈旻 郭莉 刘定新 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第1期50-61,共12页
Plasma-activated water(PAW),as an extended form of cold atmospheric-pressure plasma,greatly expands the application of plasma-based technology.The biological effects of PAW are closely related to the aqueous reactive ... Plasma-activated water(PAW),as an extended form of cold atmospheric-pressure plasma,greatly expands the application of plasma-based technology.The biological effects of PAW are closely related to the aqueous reactive species,which can be regulated by the activation process.In this study,surface plasma-activated air(SAA)and a He+O_(2)plasma jet(Jet)were parallelly combined(the SAA+Jet combination)or sequentially combined(the SAA→Jet combination and the Jet→SAA combination)to prepare plasma-activated saline(PAS).The PAS activated by the combinations exhibited stronger bactericidal effects than that activated by the SAA or the Jet alone.The concentrations of H_(2)O_(2)and NO_(2)^(-)were higher in the PAS activated by the Jet→SAA combination,while ONOO^(-)concentrations were close in the three kinds of PAS and^(1)O_(2)concentrations were higher in the PAS activated by the SAA+Jet combination.The analysis of scavengers also demonstrated that H_(2)O_(2),^(1)O_(2),and ONOO^(-)in the PAS activated by the SAA+Jet combination,and^(1)O_(2)in the PAS activated by the Jet→SAA combination played critical roles in bactericidal effects.Further,the effective placement time of the three PAS varied,and the PAS activated by the Jet→SAA combination could also inactivate 2.6-log_(10)of MRSA cells after placement for more than 60 min.The regulation of reactive species in plasma-activated water via different combinations of plasma devices could improve the directional application of plasma-activated water in the biomedical field. 展开更多
关键词 plasma-activated water surface plasma-activated air plasma jet bactericidal effect reactive species
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Magnetic diagnostics layout design for CFETR plasma equilibrium reconstruction
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作者 于庆泽 黄耀 +6 位作者 罗正平 汪悦航 刘自结 芮望颐 吴凯 肖炳甲 李建刚 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期537-543,共7页
Plasma equilibrium reconstruction provides essential information for tokamak operation and physical analysis.An extensive and reliable set of magnetic diagnostics is required to obtain accurate plasma equilibrium.This... Plasma equilibrium reconstruction provides essential information for tokamak operation and physical analysis.An extensive and reliable set of magnetic diagnostics is required to obtain accurate plasma equilibrium.This study designs and optimizes the magnetic diagnostics layout for the reconstruction of the equilibrium of the plasma according to the scientific objectives,engineering design parameters,and limitations of the Chinese Fusion Engineering Test Reactor(CFETR).Based on the CFETR discharge simulation,magnetic measurement data are employed to reconstruct consistent plasma equilibrium parameters,and magnetic diagnostics'number and position are optimized by truncated Singular value decomposition,verifying the redundancy reliability of the magnetic diagnostics layout design.This provides a design solution for the layout of the magnetic diagnostics system required to control the plasma equilibrium of CFETR,and the developed design and optimization method can provide effective support to design magnetic diagnostics systems for future magnetic confinement fusion devices. 展开更多
关键词 plasma equilibrium reconstruction EFIT code flux loops and magnetic probes optimization
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Spark plasma sintering of tungsten-based WTaVCr refractory high entropy alloys for nuclear fusion applications
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作者 Yongchul Yoo Xiang Zhang +4 位作者 Fei Wang Xin Chen Xing-Zhong Li Michael Nastasi Bai Cui 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CSCD 2024年第1期146-154,共9页
W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a po... W-based WTaVCr refractory high entropy alloys (RHEA) may be novel and promising candidate materials for plasma facing components in the first wall and diverter in fusion reactors. This alloy has been developed by a powder metallurgy process combining mechanical alloying and spark plasma sintering (SPS). The SPSed samples contained two phases, in which the matrix is RHEA with a body-centered cubic structure, while the oxide phase was most likely Ta2VO6through a combined analysis of X-ray diffraction (XRD),energy-dispersive spectroscopy (EDS), and selected area electron diffraction (SAED). The higher oxygen affinity of Ta and V may explain the preferential formation of their oxide phases based on thermodynamic calculations. Electron backscatter diffraction (EBSD) revealed an average grain size of 6.2μm. WTaVCr RHEA showed a peak compressive strength of 2997 MPa at room temperature and much higher micro-and nano-hardness than W and other W-based RHEAs in the literature. Their high Rockwell hardness can be retained to at least 1000°C. 展开更多
关键词 refractory high entropy alloy plasma-facing material fusion reactor spark plasma sintering
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Adenylate cyclase activates the cAMP signalling pathway to enhance platelet-rich plasma-treated Achilles tendon disease,a theoretical bioinformatics-based study
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作者 Jing-Yi Sun Cai Li Feng-Ying Du 《World Journal of Orthopedics》 2024年第2期192-200,共9页
The effectiveness of platelet-rich plasma(PRP)for the treatment of Achilles tendon disorders still needs to be evaluated through a series of prospective studies,but genomic analysis can reveal the existence of complem... The effectiveness of platelet-rich plasma(PRP)for the treatment of Achilles tendon disorders still needs to be evaluated through a series of prospective studies,but genomic analysis can reveal the existence of complementary PRP treatment options.Based on the 96 platelet activation-related genes in the Kyoto Encyclopedia of Genes and Genomes(KEGG)database,we performed Gene Ontology functional enrichment analysis and KEGG enrichment analysis,pathway correlation analysis,and enrichment mapping to determine the enrichment results of the gene set enrichment analysis and found that the cAMP signalling pathway may be the key to enhancing the effectiveness of PRP treatment.The cAMP signalling pathway interacts with the Rap1 signalling pathway and cGMPPKG signalling pathway to mediate the entire pathophy-siological process of Achilles tendon disease.Moreover,ADCY1-9 may be the key to the activation of the cAMP signalling network.Further based on the data in the Gene Expression Omnibus database,it was found that ADCY4 and ADCY7 may be the players that play a major role,associated with the STAT4-ADCY4-LAMA5 axis and the GRbeta-ADCY7-SEMA3C axis,which is expected to be a complementary target for enhancing the efficacy of PRP in the treatment of Achilles tendon disease. 展开更多
关键词 Platelet-rich plasma Achilles tendon disease CAMP Adenylate cyclase Complementary target
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