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Current Status and Enhancement of Collaborative Research in the World:A Case Study of Osaka University 被引量:1
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作者 Shino Iwami Toshihiko Shimizu +4 位作者 Melvin John F.Empizo Jacque Lynn F.Gabayno Nobuhiko Sarukura Shota Fujii Yoshinari Sumimura 《Journal of Data and Information Science》 CSCD 2020年第4期75-85,共11页
Purpose:The purpose of this research is to provide evidence for decision-makers to realize the potentials of collaborations between countries/regions via the scientometric analysis of co-authoring in academic publicat... Purpose:The purpose of this research is to provide evidence for decision-makers to realize the potentials of collaborations between countries/regions via the scientometric analysis of co-authoring in academic publications.Design/methodology/approach:The approach is that Osaka University,which has set a strategy to become a global campus,is positioned to have a leading role to enhance such collaborations.This research measures co-authoring relations between Osaka University and other countries/regions to identify networks for fostering strong research collaborations.Findings:Five countries are identified as candidates for the future global campuses of Osaka University based on three factors,co-authoring relations,GDP growth,and population growth.Research limitations:The main limitation of this study is not being able to use the relations by the former positions of authors in Osaka University,because the data retrieved is limited by the query of the organization name at the first step.Practical implications:The significance of this work is to provide evidence for the university strategy to expand abroad based on the quantity and visualization of trends.Originality/value:With wider practical implementations,the approach of this research is useful in making a strategic roadmap for scientific organizations that intend to collaborate internationally. 展开更多
关键词 Co-authoring University management Overseas strategy Global campus Evidence-based policy-making
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Present Status and Future Prospects of Laser Fusion Research at ILE Osaka University
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作者 K.Mima K.A.Tanaka +13 位作者 R.Kodama T.Johzaki H.Nagatomo H.Shiraga Y.Sentoku N.Miyanaga H.Azechi M.Nakai T.Norimatu K.Nagai J.Sunahara K.Nishihara T.Taguchi H.Sakagami 《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第1期2179-2184,共6页
Reviewed are the present status and future prospects of the laser fusionresearch at the ILE Osaka. The Gekko XII and Peta Watt laser system have been operated forinvestigating the implosion hydrodynamics, fast ignitio... Reviewed are the present status and future prospects of the laser fusionresearch at the ILE Osaka. The Gekko XII and Peta Watt laser system have been operated forinvestigating the implosion hydrodynamics, fast ignition, and the relativistic laser plasmainteractions and so on. In particular, the fast ignition experiments with cone shell target havebeen in progress as the UK and US-Japan collaboration programs. In the experiments, the implodedhigh density plasmas are heated by irradiating 500 J level peta-watt laser pulse. The thermalneutron yield is found to increase by three orders of magnitude by injecting the peta-watt laserinto the cone shell target. The Rayleigh-Taylor instability experiment results are also reviewed isthis paper. 展开更多
关键词 laser fusion present ststus future prospects
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Pathological and physiological functional cross-talks ofα-synuclein and tau in the central nervous system 被引量:2
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作者 Mingyue Jin Shengming Wang +3 位作者 Xiaodie Gao Zhenyou Zou Shinji Hirotsune Liyuan Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第4期855-862,共8页
α-Synuclein and tau are abundant multifunctional brain proteins that are mainly expressed in the presynaptic and axonal compartments of neurons,respectively.Previous works have revealed that intracellular deposition... α-Synuclein and tau are abundant multifunctional brain proteins that are mainly expressed in the presynaptic and axonal compartments of neurons,respectively.Previous works have revealed that intracellular deposition ofα-synuclein and/or tau causes many neurodegenerative disorders,including Alzheimer’s disease and Parkinson’s disease.Despite intense investigation,the normal physiological functions and roles ofα-synuclein and tau are still unclear,owing to the fact that mice with knockout of either of these proteins do not present apparent phenotypes.Interestingly,the co-occurrence ofα-synuclein and tau aggregates was found in post-mortem brains with synucleinopathies and tauopathies,some of which share similarities in clinical manifestations.Furthermore,the direct interaction ofα-synuclein with tau is considered to promote the fibrillization of each of the proteins in vitro and in vivo.On the other hand,our recent findings have revealed thatα-synuclein and tau are cooperatively involved in brain development in a stage-dependent manner.These findings indicate strong cross-talk between the two proteins in physiology and pathology.In this review,we provide a summary of the recent findings on the functional roles ofα-synuclein and tau in the physiological conditions and pathogenesis of neurodegenerative diseases.A deep understanding of the interplay betweenα-synuclein and tau in physiological and pathological conditions might provide novel targets for clinical diagnosis and therapeutic strategies to treat neurodegenerative diseases. 展开更多
关键词 ALPHA-SYNUCLEIN microtubule-associated protein neurodegenerative disease TAU
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Comparing role of ATP between acute pain in neuromyelitis optica spectrum disorder and peripheral neuropathic pain
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作者 Teruyuki Ishikura Tatsusada Okuno 《Neural Regeneration Research》 SCIE CAS 2025年第1期184-185,共2页
In this article, we present our previous research, which highlighted adenosine triphosphate(ATP) as the cause of neuropathic pain during the acute phase of neuromyelitis optica spectrum disorder(NMOSD). In NMOSD patho... In this article, we present our previous research, which highlighted adenosine triphosphate(ATP) as the cause of neuropathic pain during the acute phase of neuromyelitis optica spectrum disorder(NMOSD). In NMOSD pathology, damageassociated molecular patterns(DAMPs), including ATP, are released from damaged astrocytes, triggering the activation of innate immune cells. ATP is a central mediator of acute pain in NMOSD. 展开更多
关键词 PAIN ACUTE PATHOLOGY
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Poly(ethylenimine)-assisted synthesis of hollow carbon spheres comprising multi-sized Ni species for CO_(2)electroreduction
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作者 Kaining Li Yasutaka Kuwahara Hiromi Yamashita 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期66-76,共11页
Electrochemical CO_(2)reduction to produce value-added chemicals and fuels is one of the research hotspots in the field of energy conversion.The development of efficient catalysts with high conductivity and readily ac... Electrochemical CO_(2)reduction to produce value-added chemicals and fuels is one of the research hotspots in the field of energy conversion.The development of efficient catalysts with high conductivity and readily accessible active sites for CO_(2)electroreduction remains challenging yet indispensable.In this work,a reliable poly(ethyleneimine)(PEI)-assisted strategy is developed to prepare a hollow carbon nanocomposite comprising a single-site Ni-modified carbon shell and confined Ni nanoparticles(NPs)(denoted as Ni@NHCS),where PEI not only functions as a mediator to induce the highly dispersed growth of Ni NPs within hollow carbon spheres,but also as a nitrogen precursor to construct highly active atomically-dispersed Ni-Nx sites.Benefiting from the unique structural properties of Ni@NHCS,the aggregation and exposure of Ni NPs can be effectively prevented,while the accessibility of abundant catalytically active Ni-Nx sites can be ensured.As a result,Ni@NHCS exhibits a high CO partial current density of 26.9 mA cm^(-2)and a Faradaic efficiency of 93.0%at-1.0 V vs.RHE,outperforming those of its PEI-free analog.Apart from the excellent activity and selectivity,the shell confinement effect of the hollow carbon sphere endows this catalyst with long-term stability.The findings here are anticipated to help understand the structure-activity relationship in Ni-based carbon catalyst systems for electrocatalytic CO_(2)reduction.Furthermore,the PEI-assisted synthetic concept is potentially applicable to the preparation of high-performance metal-based nanoconfined materials tailored for diverse energy conversion applications and beyond. 展开更多
关键词 Hollow carbon sphere Ni nanoparticle CO_(2)reduction Electrocatalysis Single-atom catalyst
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The deterministic condition for the ground reaction force acting point on the combined knee valgus and tibial internal rotation moments in early phase of cutting maneuvers in female athletes
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作者 Issei Ogasawara Ken Ohta +4 位作者 Gajanan S.Revankar Shoji Konda Yohei Shimokochi Hideyuki Koga Ken Nakata 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第3期376-386,共11页
Background:Combined knee valgus and tibial internal rotation(VL+IR)moments have been shown to stress the anterior cruciate ligament(ACL)in several in vitro cadaveric studies.To utilize this knowledge for non-contact A... Background:Combined knee valgus and tibial internal rotation(VL+IR)moments have been shown to stress the anterior cruciate ligament(ACL)in several in vitro cadaveric studies.To utilize this knowledge for non-contact ACL injury prevention in sports,it is necessary to elucidate how the ground reaction force(GRF)acting point(center of pressure(CoP))in the stance foot produces combined knee VL+IR moments in risky maneuvers,such as cuttings.However,the effects of the GRF acting point on the development of the combined knee VL+IR moment in cutting are still unknown.Methods:We first established the deterministic mechanical condition that the CoP position relative to the tibial rotational axis differentiates the GRF vector’s directional probability for developing the combined knee VL+IR moment,and theoretically predicted that when the CoP is posterior to the tibial rotational axis,the GRF vector is more likely to produce the combined knee VL+IR moment than when the CoP is anterior to the tibial rotational axis.Then,we tested a stochastic aspect of our theory in a lab-controlled in vivo experiment.Fourteen females performed 60˚cutting under forefoot/rearfoot strike conditions(10 trials each).The positions of lower limb markers and GRF data were measured,and the knee moment due to GRF vector was calculated.The trials were divided into anterior-and posterior-CoP groups depending on the CoP position relative to the tibial rotational axis at each 10 ms interval from 0 to 100 ms after foot strike,and the occurrence rate of the combined knee VL+IR moment was compared between trial groups.Results:The posterior-CoP group showed significantly higher occurrence rates of the combined knee VL+IR moment(maximum of 82.8%)at every time point than those of the anterior-CoP trials,as theoretically predicted by the deterministic mechanical condition.Conclusion:The rearfoot strikes inducing the posterior CoP should be avoided to reduce the risk of non-contact ACL injury associated with the combined knee VL+IR stress. 展开更多
关键词 Center of pressure Deterministic condition Foot strike pattern Injury mechanism Moment of ground reaction force
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The 5αcondensate state in 20Ne
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作者 Takahiro Kawabata 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期3-5,共3页
Theclustering phenomenon,in which nucleons are arranged intoparticles(4 He nuclei)within a nuclear system,is one of the most intriguing aspects of nuclear structure.It has been observed in various light nuclei,such as... Theclustering phenomenon,in which nucleons are arranged intoparticles(4 He nuclei)within a nuclear system,is one of the most intriguing aspects of nuclear structure.It has been observed in various light nuclei,such as^(8)Be,^(12)C,^(16)O,and^(20)Ne,and is responsible for many exotic and fascinating phenomena,such as the Hoyle state in^(12)C,which plays an essential role in stellar nucleosynthesis[1-6]as well as in heavy-ion collisions[7-9]. 展开更多
关键词 STRUCTURE STATE
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Experimental measurements of gamma-photon production and estimation of electron/positron production on the PETAL laser facility
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作者 F.Brun L.Ribotte +14 位作者 G.Boutoux X.Davoine P.E.Masson-Laborde Y.Sentoku N.Iwata N.Blanchot D.Batani I.Lantuéjoul L.Lecherbourg B.Rosse C.Rousseaux B.Vauzour D.Raffestin E.D’Humières X.Ribeyre 《Matter and Radiation at Extremes》 SCIE EI CSCD 2024年第5期32-47,共16页
This article reports the first measurements of high-energy photons produced with the high-intensity PETawatt Aquitaine Laser(PETAL)laser.The experiments were performed during the commissioning of the laser.The laser h... This article reports the first measurements of high-energy photons produced with the high-intensity PETawatt Aquitaine Laser(PETAL)laser.The experiments were performed during the commissioning of the laser.The laser had an energy of about 400 J,an intensity of 8×10^(18)W cm^(−2),and a pulse duration of 660 fs(FWHM).It was shot at a 2 mm-thick solid tungsten target.The high-energy photons were produced mainly from the bremsstrahlung process for relativistic electrons accelerated inside a plasma generated on the front side of the target.This paper reports measurements of electrons,protons and photons.Hot electrons up to35 MeV with a few-MeV temperature were recorded by a spectrometer,called SESAME(SpectreÉlectronS Angulaire MoyenneÉnergie).K-and L-shells were clearly detected by a photon spectrometer called SPECTIX(Spectromètre PetalàCristal en TransmIssion pour le rayonnnement X).High-energy photons were diagnosed by CRACC-X(Cassette de RAdiographie Centre Chambre-rayonnement X),a bremsstrahlung cannon.Bremsstrahlung cannon analysis is strongly dependent on the hypothesis adopted for the spectral shape.Different shapes can exhibit similar reproductions of the experimental data.To eliminate dependence on the shape hypothesis and to facilitate analysis of the data,simulations of the interaction were performed.To model the mechanisms involved,a simulation chain including hydrodynamic,particle-in-cell,and Monte Carlo simulations was used.The simulations model the preplasma generated at the front of the target by the PETAL laser prepulse,the acceleration of electrons inside the plasma,the generation of MeV-range photons from these electrons,and the response of the detector impacted by the energetic photon beam.All this work enabled reproduction of the experimental data.The high-energy photons produced have a large emission angle and an exponential distribution shape.In addition to the analysis of the photon spectra,positron production was also investigated.Indeed,if high-energy photons are generated inside the solid target,some positron/electron pairs may be produced by the Bethe–Heitler process.Therefore,the positron production achievable within the PETAL laser facility was quantified.To conclude the study,the possibility of creating electron/positron pairs through the linear Breit–Wheeler process with PETAL was investigated. 展开更多
关键词 process. POSITRON HYPOTHESIS
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Construction and performance test of charged particle detector array for MATE
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作者 Xiao‑Bin Li Long‑Hui Ru +14 位作者 Zhi‑Chao Zhang Bing‑Feng Lv Ning‑Tao Zhang Jin‑Long Zhang Chen‑Gui Lu Bing‑Shui Gao Jun‑Bing Ma Fu‑Shuai Shi Satoru Terashima Xiao‑Dong Xu Zhen Bai Shi‑Wei Xu Yan‑Yun Yang Hooi‑Jin Ong Xiao‑Dong Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期92-100,共9页
A charged particle array named MATE-PA,which serves as an auxiliary detector system for a Multi-purpose Active-target Time projection chamber used in nuclear astrophysical and exotic beam Experiments(MATE),was constru... A charged particle array named MATE-PA,which serves as an auxiliary detector system for a Multi-purpose Active-target Time projection chamber used in nuclear astrophysical and exotic beam Experiments(MATE),was constructed.The array comprised of 20 single-sided strip-silicon detectors covering approximately 10%of the solid angle.The detectors facilitated the detection of reaction-induced charged particles that penetrate the active volume of the MATE.The performance of MATE-PA has been experimentally studied using an alpha source and a 36-MeV 14 N beam injected into the MATE chamber on the radioactive ion beam line in Lanzhou(RIBLL).The chamber was filled with a gas mixture of 95%4 He and 5%CO_(2) at a pressure of 500 mbar.The results indicated good separation of light-charged particles using the forward double-layer silicon detectors of MATE-PA.The energy resolution of the Si detectors was deduced to be approximately 1%(σ)for an energy loss of approximately 10 MeV caused by theαparticles.The inclusion of MATE-PA improves particle identification and increases the dynamic range of the kinetic energy of charged particles,particularly that of theαparticles,up to approximately 15 MeV. 展开更多
关键词 Silicon detector array Active target Time projection chamber
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World Class Elite Breaststrokers Downward Kick EMG Muscle Activity of the Gluteus Maximus, Quadriceps Femoris, Hamstring, Gastrocnemius Medialis, Rectus Abdominal, and Erector Spinae
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作者 Takahisa Ide William F.Johnson +10 位作者 Sadafumi Takise Noriko Inada Hiromasa Fujimori Takeharu Fujimori Emi Moronuki Ai Soma Kazuki Watanabe Asahi Nagahata Iryna Glavnyk Mark Nikolaev Bogdan Plavin 《Psychology Research》 2024年第2期64-69,共6页
This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,qua... This study analyzed the difference between using a downward breaststroke kick and a horizontal breaststroke kick in a sample of world class elite swimmers.We compared average muscle activity of the gluteus maximus,quadriceps femoris(vastus medialis and rectus femoris),hamstring/long head of the biceps femoris,gastrocnemius medialis,rectus abdominal,and erector spinae when using the downward breaststroke kick technique.We find that when this sample of swimmers utilized the downward breaststroke kick,max speed and velocity per stroke increased,measured by 12,788 EMG samples,where the results are highly correlated to duration of the aerodynamic buoyant force in breaststroke kick technique.The increases in performance observed from measuring the world class elite swimmers is highly correlated to the duration of the kick aerodynamic buoyant force.Among this sample of elite swimmers,the longer a swimmer demonstrates a buoyant force breaststroke kick,the lower the time in a 100 breaststroke. 展开更多
关键词 swimming breaststroke downward kick EMG imagination world class elite swimmers
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The Development of a Feeding Coparenting Scale for Japanese Parents of Fifth- and Sixth-Grade Elementary School Children
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作者 Maiko Yasuzato Tae Kawahara +2 位作者 Yuichi Nakayama Cin Cin Tan Akemi Yamazaki 《Open Journal of Nursing》 2024年第1期27-39,共13页
Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their ... Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their children was developed in the United States in 2019. However, there is no valid and reliable measure to assess feeding coparenting among caregivers of school-aged children in Japan. Therefore, this study aimed to develop a Japanese version of the FCS (FCS-J) questionnaire for caregivers with school-aged children. Methods: This was a web-based cross-sectional survey completed by caregivers of children aged 10-12 years. A preliminary survey using interviews and a web-based survey was conducted and found that the translated items of the FCS into Japanese were understandable to Japanese people. The developed survey was administered to parents of children at an elementary school. The reliability of the survey was assessed using both test-retest reliability and internal consistency analysis. Exploratory factor analysis was used to test construct validity, and known population validity was examined in relation to attributes, marital satisfaction, and feeding tasks. Results: Findings with 135 parents of school-aged children showed good internal reliability and validity of the FCS-J. The mean score for the overall FCS-J score was 46.2 (SD = 6.2), with Cronbach’s α of 0.72. For the subscales, Cronbach’s α ranged from 0.75 to 0.79. In sum, the present study’s results support the three-factor structure of the FCS in Japanese caregivers in Japan. Conclusions: The developed FCS-J was found to have a certain degree of reliability and validity. In this study, a Japanese version of the FCS-J was developed. . 展开更多
关键词 CHILD Coparenting PARENTS Feeding Coparenting
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Surface and Content Validity of the Mentoring Function Scale for Novice Nurses
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作者 Aimi Furukawa Yasuko Hosoda 《Open Journal of Nursing》 2024年第8期401-411,共11页
This study aimed to examine the surface and content validity of the Mentoring Function Scale for Novice Nurses, used to assess the mentoring of entry-level nurses, and to refine the scale items. In Study 1, six nurse ... This study aimed to examine the surface and content validity of the Mentoring Function Scale for Novice Nurses, used to assess the mentoring of entry-level nurses, and to refine the scale items. In Study 1, six nurse education researchers, selected using convenience sampling, with five or more years of nursing experience and experience teaching novice nurses, were invited to an expert meeting in July 2015. A group interview was conducted that lasted approximately 120 minutes. Study 2 examined the content validity index. Between September and November 2015, we distributed a self-administered questionnaire survey to 11 participants selected by convenience sampling. The participants included five nurse education researchers with a minimum of five years of nursing experience and experience teaching novice nurses, as well as six clinical nurses with a master’s degree or higher. Finally, 81 questionnaire items were retained from the initial 125 items. The 81-item Mentoring Function Scale for Novice Nurses had higher content validity than the original scale. To further increase the scale’s applicability, future studies should assess its reliability, construct validity, and criterion-related validity. 展开更多
关键词 Novice Nurses Mentoring Function Surface and Content Validity Item-Level Content Validity Index
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Opportunities for production and property research of neutron-rich nuclei around N=126 at HIAF
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作者 Shao-Bo Ma Li-Na Sheng +9 位作者 Xue-Heng Zhang Shi-Tao Wang Kai-Long Wang Chun-Wang Ma Hool-Jin Ong Zhi-Yu Sun Shu-Wen Tang Yu-Hong Yu Xin-Tong Du Xiao-Bao Wei 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第6期101-113,共13页
The study of nuclide production and its properties in the N=126 neutron-rich region is prevalent in nuclear physics and astrophysics research.The upcoming High-energy FRagment Separator(HFRS)at the High-Intensity heav... The study of nuclide production and its properties in the N=126 neutron-rich region is prevalent in nuclear physics and astrophysics research.The upcoming High-energy FRagment Separator(HFRS)at the High-Intensity heavy-ion Accelerator Facility(HIAF),an in-flight separator at relativistic energies,is characterized by high beam intensity,large ion-optical acceptance,high magnetic rigidity,and high momentum resolution power.This provides an opportunity to study the production and properties of neutron-rich nuclei around N=126.In this paper,an experimental scheme is proposed to produce neutron-rich nuclei around N=126 and simultaneously measure their mass and lifetime based on the HFRS separator;the feasibility of this scheme is evaluated through simulations.The results show that under the high-resolution optical mode,many new neutron-rich nuclei approaching the r-process abundance peak around A=195 can be produced for the first time,and many nuclei with unknown masses and lifetimes can be produced with high statistics.Using the time-of-flight corrected by the measured dispersive position and energy loss information,the cocktails produced from 208 Pb fragmentation can be unambiguously identified.Moreover,the masses of some neutron-rich nuclei near N=126 can be measured with high precision using the time-of-flight magnetic rigidity technique.This indicates that the HIAF-HFRS facility has the potential for the production and property research of neutron-rich nuclei around N=126,which is of great significance for expanding the chart of nuclides,developing nuclear theories,and understanding the origin of heavy elements in the universe. 展开更多
关键词 HFRS FRAGMENTATION Neutron-rich nuclei around N=126 Mass measurement LIFETIME
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Electroencephalogram Signal Correlations between Default Mode Network and Attentional Functioning
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作者 Moemi Matsuo Takashi Higuchi +3 位作者 Toranosuke Abe Takuya Ishibashi Ayano Egashira Rio Kamashita 《Journal of Behavioral and Brain Science》 2024年第4期119-134,共16页
Attentional issues may affect acquiring new information, task performance, and learning. Cortical network activities change during different functional brain states, including the default mode network (DMN) and attent... Attentional issues may affect acquiring new information, task performance, and learning. Cortical network activities change during different functional brain states, including the default mode network (DMN) and attention network. We investigated the neural mechanisms underlying attentional functions and correlations between DMN connectivity and attentional function using the Trail-Making Test (TMT)-A and -B. Electroencephalography recordings were performed by placing 19 scalp electrodes per the 10 - 20 system. The mean power level was calculated for each rest and task condition. Non-parametric Spearman’s rank correlation was used to examine the correlation in power levels between the rest and TMT conditions. The most significant correlations during TMT-A were observed in the high gamma wave, followed by theta and beta waves, indicating that most correlations were in the parietal lobe, followed by the frontal, central, and temporal lobes. The most significant correlations during TMT-B were observed in the beta wave, followed by the high and low gamma waves, indicating that most correlations were in the temporal lobe, followed by the parietal, frontal, and central lobes. Frontoparietal beta and gamma waves in the DMN may represent attentional functions. 展开更多
关键词 Cortical Network Activities ELECTROENCEPHALOGRAPHY ATTENTION Default Mode Network
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Boundary Conditions for Momentum and Vorticity at an Interface between Two Fluids
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作者 Korekazu Ueyama 《Journal of Applied Mathematics and Physics》 2024年第1期16-33,共18页
Boundary conditions for momentum and vorticity have been precisely derived, paying attention to the physical meaning of each mathematical expression of terms rigorously obtained from the basic equations: Navier-Stokes... Boundary conditions for momentum and vorticity have been precisely derived, paying attention to the physical meaning of each mathematical expression of terms rigorously obtained from the basic equations: Navier-Stokes equation and the equation of vorticity transport. It has been shown first that a contribution of fluid molecules crossing over a conceptual surface moving with fluid velocity due to their fluctuating motion is essentially important to understanding transport phenomena of momentum and vorticity. A notion of surface layers, which are thin layers at both sides of an interface, has been introduced next to elucidate the transporting mechanism of momentum and vorticity from one phase to the other at an interface through which no fluid molecules are crossing over. A fact that a size of  δV, in which reliable values of density, momentum, and velocity of fluid are respectively defined as a volume-averaged mass of fluid molecules, a volume-averaged momentum of fluid molecules and a mass-averaged velocity of fluid molecules, is not infinitesimal but finite has been one of the key factors leading to the boundary conditions for vorticity at an interface between two fluids. The most distinguished characteristics of the boundary conditions derived here are the zero-value conditions for a normal component of momentum flux and tangential components of vorticity flux, at an interface. 展开更多
关键词 Boundary Condition for Vorticity Surface Layer INTERFACE Momentum Flux Vorticity Flux
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Enhancement of Visual Attention by Color Revealed Using Electroencephalography
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作者 Moemi Matsuo Takashi Higuchi +3 位作者 Takuya Ishibashi Ayano Egashira Toranosuke Abe Hiroya Miyabara 《Open Journal of Therapy and Rehabilitation》 2024年第1期1-9,共9页
Attention constitutes a fundamental psychological feature guiding our mental effort toward specific objects, concurrent with processes such as memory, reasoning, and imagination. Visual attention, crucial for selectin... Attention constitutes a fundamental psychological feature guiding our mental effort toward specific objects, concurrent with processes such as memory, reasoning, and imagination. Visual attention, crucial for selecting surrounding information, often decreases in older adults and patients with cerebrovascular disorders. Effective methods to enhance attention are scarce. Here, we investigated whether color information influences visual attention and brain activity during task performance, utilizing EEG. We examined 13 healthy young adults (seven women and six men;mean age: 21.2 ± 0.58 years) using 19-electrode electroencephalograms to assess the impact of color information on visual attention. The Clinical Assessment for Attention cancellation test was conducted under the black, red, and blue color conditions. Wilcoxon’s signed-rank test was used to assess differences in task performance (task time and error) between conditions. Spearman’s rank correlation was utilized to examine the correlation in power levels between task performance and color conditions. Significant variations in total task errors were observed among color conditions. The black condition exhibited the highest error frequency (0.7 ± 0.9 times), followed by the red condition (0.5 ± 0.8 times), with the lowest error frequency occurring in the blue (0.2 ± 0.4 times) condition (black vs. red: P = 0.03;black vs. blue: P = 0.00;red vs. blue: P = 0.032). No time difference was observed. The black condition showed negative delta and high-gamma correlations in the central electrodes. The red condition revealed positive alpha and low-gamma correlations in the frontal and occipital areas. Although no correlations were observed in the blue condition, it enhanced attentional performance. Positive alpha and low-gamma waves might be crucial for spotting attentional errors in key areas. Our findings provide insights into the effects of color information on visual attention and potential neural correlates associated with attentional processes. In conclusion, our study implies a connection between color information and attentional task performance, with blue font associated with the most accurate performance. 展开更多
关键词 ATTENTION Higher Brain Function ELECTROENCEPHALOGRAPHY NEUROIMAGING REHABILITATION
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Fundamental Study on Response Properties of Structures Constructed on Lunar Regolith
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作者 Yuji Miyamoto Takaharu Nakano Toshio Kobayashi 《Open Journal of Earthquake Research》 2024年第1期27-40,共14页
The Artemis Program, for constructing the lunar base, is in progress. How to design and construct architectural and civil engineering structures in the lunar environment has become an important issue. The lunar surfac... The Artemis Program, for constructing the lunar base, is in progress. How to design and construct architectural and civil engineering structures in the lunar environment has become an important issue. The lunar surface is covered with soft sand, called regolith, and it is required to protect lunar bases and structures, as well as internal precision equipment, against vibrational disturbances such as moonquakes and meteorite collisions. Therefore, in this study, the static and cyclic triaxial compression tests of the regolith simulant were conducted. The reference strain and equivalent damping factor of the regolith simulant were smaller compared to sandy soil on Earth. In addition, a shaking table test using model specimens was conducted on the response properties of regolith ground alone and structures set on regolith ground. The buried foundation and pile foundation notably suppressed the horizontal response attributed to the rocking component compared to a direct foundation. 展开更多
关键词 Lunar Development REGOLITH Soil-Structure Interaction Triaxial Compression Test Shaking Table Test
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The Application of Thermomechanical Dynamics (TMD) to Thermoelectric Energy Generation by Employing a Low Temperature Stirling Engine
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2024年第9期3185-3207,共23页
A thermoelectric generation Stirling engine (TEG-Stirling engine) is discussed by employing a low temperature Stirling engine and the dissipative equation of motion derived from the method of thermomechanical dynamics... A thermoelectric generation Stirling engine (TEG-Stirling engine) is discussed by employing a low temperature Stirling engine and the dissipative equation of motion derived from the method of thermomechanical dynamics (TMD). The results and mechanism of axial flux electromagnetic induction (AF-EMI) are applied to a low temperature Stirling engine, resulting in a TEG-Stirling engine. The method of TMD produced thermodynamically consistent and time-dependent physical quantities for the first time, such as internal energy ℰ(t), thermodynamic work Wth(t), the total entropy (heat dissipation) Qd(t)and measure or temperature of a nonequilibrium state T˜(t). The TMD analysis produced a lightweight mechanical system of TEG-Stirling engine which derives electric power from waste heat of temperature (40˚CT100˚C) by a thermoelectric conversion method. An optimal low rotational speed about 30θ′(t)/(2π)60(rpm) is found, applicable to devices for sustainable, clean energy technologies. The stability of a thermal state and angular rotations of TEG-Stirling engine are specifically shown by employing properties of nonequilibrium temperature T˜(t), which is also applied to study optimal fuel-injection and combustion timings of heat engines. 展开更多
关键词 Thermoelectric Generation Stirling Engine (TEG-Stirling Engine) Thermomechanical Dynamics (TMD) Time-Dependent Nonequilibrium Temperature Stability of Heat Engines in a Thermal State Optimal Fuel-Injection and Combustion Timings
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Thermoelectric Stirling Engine (TEG-Stirling Engine) Based on the Analysis of Thermomechanical Dynamics (TMD)
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2024年第7期2386-2399,共14页
The thermoelectric energy conversion technique by employing the Disk-Magnet Electromagnetic Induction (DM-EMI) is examined in detail, and possible applications to heat engines as one of the energy-harvesting technolog... The thermoelectric energy conversion technique by employing the Disk-Magnet Electromagnetic Induction (DM-EMI) is examined in detail, and possible applications to heat engines as one of the energy-harvesting technologies are discussed. The idea is induced by the analysis of thermomechanical dynamics (TMD) for a nonequilibrium irreversible thermodynamic system of heat engines, such as a drinking bird and a low temperature Stirling engine, resulting in thermoelectric energy generation different from conventional heat engines. The current thermoelectric energy conversion with DM-EMI can be applied to wide ranges of machines and temperature differences. The mechanism of DM-EMI energy converter is categorized as the axial flux generator (AFG), which is the reason why the technology is applicable to sensitive thermoelectric conversions. On the other hand, almost all the conventional turbines use the radius flux generator to extract huge electric power, which uses the radial flux generator (RFG). The axial flux generator is helpful for a low mechanoelectric energy conversion and activations of waste heat from macroscopic energy generators such as wind, geothermal, thermal, nuclear power plants and heat-dissipation lines. The technique of DM-EMI will contribute to solving environmental problems to maintain clean and sustainable energy as one of the energy harvesting technologies. 展开更多
关键词 A Low Temperature Stirling Engine Axial Flux Generator Thermomechanical Dynamics (TMD) Thermoelectric Energy Conversions
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Thermomechanical Dynamics (TMD) and Bifurcation-Integration Solutions in Nonlinear Differential Equations with Time-Dependent Coefficients
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作者 Hiroshi Uechi Lisa Uechi Schun T. Uechi 《Journal of Applied Mathematics and Physics》 2024年第5期1733-1743,共11页
The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple ba... The new independent solutions of the nonlinear differential equation with time-dependent coefficients (NDE-TC) are discussed, for the first time, by employing experimental device called a drinking bird whose simple back-and-forth motion develops into water drinking motion. The solution to a drinking bird equation of motion manifests itself the transition from thermodynamic equilibrium to nonequilibrium irreversible states. The independent solution signifying a nonequilibrium thermal state seems to be constructed as if two independent bifurcation solutions are synthesized, and so, the solution is tentatively termed as the bifurcation-integration solution. The bifurcation-integration solution expresses the transition from mechanical and thermodynamic equilibrium to a nonequilibrium irreversible state, which is explicitly shown by the nonlinear differential equation with time-dependent coefficients (NDE-TC). The analysis established a new theoretical approach to nonequilibrium irreversible states, thermomechanical dynamics (TMD). The TMD method enables one to obtain thermodynamically consistent and time-dependent progresses of thermodynamic quantities, by employing the bifurcation-integration solutions of NDE-TC. We hope that the basic properties of bifurcation-integration solutions will be studied and investigated further in mathematics, physics, chemistry and nonlinear sciences in general. 展开更多
关键词 The Nonlinear Differential Equation with Time-Dependent Coefficients The Bifurcation-Integration Solution Nonequilibrium Irreversible States Thermomechanical Dynamics (TMD)
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