Xiaoxi Fu - Academia.edu (original) (raw)
Papers by Xiaoxi Fu
International Conference on Electronic Information Engineering, Big Data, and Computer Technology (EIBDCT 2022), May 6, 2022
The Journal of Chemical Physics
The tantalum anion has the most complicated photoelectron spectrum among all atomic anions of tra... more The tantalum anion has the most complicated photoelectron spectrum among all atomic anions of transition elements, which was the main obstacle to accurately measure its electron affinity via the generic method. The latest experimental value of the electron affinity of Ta was 0.323(12) eV, reported by Feigerle et al. [J. Chem. Phys. 74, 1580 (1981)]. In the present work, we report the high-resolution photoelectron spectroscopy of Ta− via the slow-electron velocity-map imaging method combined with a cryogenic ion trap. The electron affinity of Ta was measured to be 2652.38(17) cm−1 or 0.328 859(23) eV. Three excited states 5 D1, 3 P0, and 5 D2 of Ta− were observed, and their energy levels were determined to be 1169.64(17) cm−1 for 5 D1, 1735.9(10) cm−1 for 3 P0, and 2320.1(20) cm−1 for 5 D2 above the ground state 5 D0, respectively.
Additional file 1. The dynamic fluorescence changes of ipsilateral VPM neuronal activity during C... more Additional file 1. The dynamic fluorescence changes of ipsilateral VPM neuronal activity during CSD in awake mice. The increase in neural activity in the VPM induced by CSD showed a "propagating-like" spatial pattern that spread from the posterior-lateral to the anterior-medial side of the VPM. The left side showed the original fluorescence signal, the right side showed the relative fluorescence change.
Additional file 2. The dynamic fluorescence changes of contralateral VPM neuronal activity during... more Additional file 2. The dynamic fluorescence changes of contralateral VPM neuronal activity during CSD in awake mice. No significant activation of VGluT2 neurons was observed in the VPM after CSD induction in the contralateral cortex. The changed fluorescence signal was highly correlated with the motion of mice.
SXFEL-UF, a soft X-ray FEL user facility located in Shanghai, has been upgraded from the existing... more SXFEL-UF, a soft X-ray FEL user facility located in Shanghai, has been upgraded from the existing test facility. Electron energy increases from 840 MeV to 1.5 GeV and a SASE FEL line will be added besides the existing seeding FEL line. It has started commissioning since early this year. In order for simultaneous operation of the two FEL lines, a beam switchyard is built between the linac and the two FEL lines. In this paper, the physics design of the beam switchyard is described.
In shanghai, a hard X-ray free electron laser project named SHINE is under design. It will be bas... more In shanghai, a hard X-ray free electron laser project named SHINE is under design. It will be based on a superconducting linac running in CW mode. On the first stage, there will be three parallel undulator lines downstream the linac. For simultaneous operation of the three undulator lines, a beam distribution system based on fast kickers will be installed between linac and undulator lines. The physics design of this beam distribution system is described in this paper.
The Journal of Headache and Pain, 2022
Background As the relay centre for processing sensory information, the thalamus may involve in th... more Background As the relay centre for processing sensory information, the thalamus may involve in the abnormal sensory procedure caused by cortical spreading depression (CSD). However, few studies have focused on the transient response of thalamus during CSD. Our study aimed to investigate the neuronal activity of mouse thalamus ventral posteromedial nucleus (VPM) during CSD by in vivo micro-endoscopic fluorescence imaging of the genetic calcium probe GCaMP6s expressed in excitatory glutamatergic neurons. Methods Thirty-four transgenic VGluT2-GCaMP6s mice were used in the experiments. An endoscope was inserted into the VPM for image acquisition. CSD was induced by KCl topically applied unilaterally on the cranial dura. Data were acquired in awake (ipsilateral or contralateral VPM, saline instead of KCl, MK-801 treatment) and anaesthetized (isoflurane, pentobarbital) states. Statistical analysis was performed using analysis of variance (ANOVA) by SPSS. Results We found that after CSD in...
International Journal of Innovative Computing and Applications, 2021
The process of excavation and unloading of a deep subway foundation pit will cause deformation of... more The process of excavation and unloading of a deep subway foundation pit will cause deformation of the surrounding buildings. There are significant differences in building deformation due to different methods of supporting the foundation pit and building foundation forms. This study takes the deep foundation pit project of the station as an example to investigate this difference. A three-dimensional numerical finite element model of a deep foundation pit has been established that considers different types of building foundations (independent foundation, box foundation, and pile foundation). The sensitivity of the two supporting methods of the diaphragm wall and the combined support of isolation pile and diaphragm wall regarding the maximum settlement value of the building, the horizontal inclination value, the slope angle, and the foundation angular distortions were analyzed. Finally, the sensitivity of the length of the isolated pile to the maximum settlement value and the horizonta...
Nutrients, 2021
Inconsistent conclusions from infant sleep and feeding studies may influence parents feeding-rela... more Inconsistent conclusions from infant sleep and feeding studies may influence parents feeding-related decisions. This study aimed to systematically review the existing literature on infant sleep and its relation to the timing of introduction to complementary foods and type of milk feeding to better understand their role(s) in infant sleep. Cohort, longitudinal, cross-sectional studies, and controlled trials were identified using online searches of five databases up to April 2020. Twenty-one articles with a total of 6225 infants under 12 months-of-age were eligible. Exclusively breastfed infants (≤6 months-of-age) had a greater number of night wakings, but most studies (67%) reported no difference in night-time and 24 h sleep duration compared to formula-fed infants. However, after 6 months-of-age, most studies (>65%) reported breastfed infants to sleep less in the night-time and over 24 h compared to formula-fed infants. Furthermore, studies reported no association between the tim...
The Journal of Chemical Physics, 2021
Gold fluoride is a very unique species. In this work, we reported the resonant photodetachment sp... more Gold fluoride is a very unique species. In this work, we reported the resonant photodetachment spectra of cryogenically cooled AuF- via the slow-electron velocity-map imaging method. We determined the electron affinity of AuF to be 17 976(8) cm-1 or 2.2287(10) eV. We observed a dipole-bound state with a binding energy of 24(8) cm-1, a valence excited state with a binding energy of 1222(11) cm-1, and a resonant state with an energy of 814(12) cm-1 above the photodetachment threshold. An unusual vibrational transition with Δn = -3 was observed in the autodetachment from the dipole-bound state. Moreover, two excited states of neutral AuF were recognized for the first time, located at 13 720(78) cm-1 and 16 188(44) cm-1 above the AuF ground state.
Photonics, 2021
External seeded free-electron lasers (FELs) hold promising prospects for producing intense cohere... more External seeded free-electron lasers (FELs) hold promising prospects for producing intense coherent radiation at high harmonics of a conventional laser. The practical harmonic up-conversion efficiencies of current seeding techniques are limited by various three-dimensional effects on the electron beam. In this paper, a novel method is proposed to extend the wavelength coverage of a seeded FEL by combining the reverse taper undulator with the echo-enabled harmonic generation. The proposed technique can significantly enhance the bunching at ultra-high harmonics and preserve the electron beam qualities from degradation by deleterious effects. Theoretical analysis and numerical simulation are performed, and the results demonstrate that stable, intense, nearly fully coherent FEL pulses with photon energy up to 1 keV can be generated. The proposed technique may open up new opportunities to obtain laser-like pulses at sub-nanometer wavelength.
Arabian Journal of Geosciences, 2021
The protection of adjacent buildings is an important part of the safety control of the constructi... more The protection of adjacent buildings is an important part of the safety control of the construction of a deep foundation pit in a subway station, and a reasonable supporting method is the key to safety control. Based on the deep foundation pit project of the Nanning Metro Line 5 station in Guangxi, this paper proposes a method of combined support of the isolation pile and the diaphragm wall for the protection of buildings adjacent to the foundation pit. The three-dimensional finite element method is used to simulate the deformation law of the foundation pit adjacent to the building under the combined support during the entire excavation process, and the deformation characteristics of the isolation pile-diaphragm wall are also analyzed. The results show that compared to the diaphragm wall support method, the combined support method effectively limits the soil settlement. The maximum value of soil settlement behind the diaphragm wall is only 0.044%He (He is the excavation depth), and the position of the maximum settlement has moved to the place which far away from adjacent buildings. The maximum deformation value of the combined support method is 59.1% less than that of the diaphragm wall method, and the additional deformation of the building is controlled within 9 mm. The combined support method of isolation pile and underground diaphragm wall proposed in this paper is applied to practical engineering, and the results of field monitoring agree well with the numerical results. Therefore, it is feasible to adopt this support method for the protection of buildings adjacent to the foundation pit.
Physical Review A, 2021
Despite the fact that the laser cooling method is a well-established technique to obtain ultra-co... more Despite the fact that the laser cooling method is a well-established technique to obtain ultra-cold neutral atoms and atomic cations, it has so far never been applied to atomic anions due to the lack of suitable electric-dipole transitions. Efforts of more than a decade currently have Laas the only promising candidate for laser cooling. Our previous work [Tang et al., Phys. Rev. Lett. (2019) accept] showed that This also a potential candidate. Here we report on a combination of experimental and theoretical studies to determine the relevant transition frequencies, transition rates, and branching ratios in Th-. The resonant frequency of the laser cooling transition is determined to be /c= 4118.0 (10) cm-1. The transition rate is calculated as A=1.1710 4 s 1. The branching fraction to dark states is very small, 1.47×10-10 , thus this represents an ideal closed cycle for laser cooling. Since Th has zero nuclear spin, it is an excellent candidate to be used to sympathetically cool antiprotons in a Penning trap. The achievement of Bose-Einstein condensation, precision spectroscopy, and tests of fundamental symmetries has opened a new chapter in atomic and molecular physics. The main driving force behind this achievement is the ability to cool atoms and positive ions to K or even lower temperatures via laser cooling techniques. Although laser cooling is a well-established technique for producing ultracold neutral atoms and positive ions, it has not yet been achieved for negative ions. In principle, once we produce ultracold ensembles of a specific anion system, we can use them to sympathetically cool any anions, ranging from elementary particles to molecular anions, which will promote the research of cold plasma[1], ultracold chemistry[2], and fundamental-physics tests[3-8]. In contrast to neutral atoms and positive ions, which have an infinite number of bound states, negative ions have only a single bound state in most cases. The reason is that in atomic anions, the excess
International Journal of Innovative Computing and Applications, 2021
Quality of Life Research, 2020
Purpose Social isolation in older adults is a major public health problem and associated with inc... more Purpose Social isolation in older adults is a major public health problem and associated with increased morbidity and mortality. There are limited data on the association between social isolation and physical function including gait speed. Hence, this study is to determine the prevalence of social isolation and its association with gait speed, frailty, cognition, depression and comorbidities amongst community-dwelling older adults. Methods Social isolation, depression, frailty and perceived general health were assessed using 6-item Lubben Social Network Scale (LSNS-6), Geriatric Depression Scale (GDS), FRAIL scale and EuroQol EQ-5D-5L questionnaire which includes EQ Visual Analogue Scale (EQ-VAS), respectively. Cognition was assessed using the Chinese Mini Mental State Examination (cMMSE), while physical performance test included gait speed and short physical performance battery test. Binary logistic regression was performed to determine the influence of socio-demographic, medical, functional and cognitive variables on social isolation. Results Out of 202 participants, 27.7% were robust, 66.8% of participants were pre-frail, and 5.4% of participants were frail. Almost half (45.5%, n = 92) of the participants were found to be at risk of social isolation. A poor social network was negatively associated with mean gait speed (OR = 0.674, CI 0.464-0.979, p = 0.039), EQ-VAS (OR = 0.561, CI 0.390-0.806, p < 0.01) and cMMSE (OR = 0.630, 95% CI 0.413-0.960, p = 0.032). Conclusion Almost half of older adults in the community are at risk of social isolation with a very significant association with gait speed, cMMSE and EQ-VAS scores.
The Journal of Chemical Physics, 2020
We report the high-resolution photoelectron spectra of negative gallium anions obtained via the s... more We report the high-resolution photoelectron spectra of negative gallium anions obtained via the slow-electron velocity-map imaging method. The electron affinity of Ga is determined to be 2429.07(12) cm −1 or 0.301 166(14) eV. The fine structures of Ga are well resolved: 187.31(22) cm −1 or 23.223(27) meV for 3 P 1 and 502.70(28) cm −1 or 62.327(35) meV for 3 P 2 above the ground state 3 P 0 , respectively. The photoelectron angular distribution for photodetachment from Ga − (4s 2 4p 2 3 P 0) to Ga(4s 2 5s 2 S 1/2) is measured. An unexpected perpendicular distribution instead of an isotropic distribution is observed, which is due to a resonance near 3.3780 eV.
Physical Review A, 2020
Electron affinities (EAs) of many lanthanide elements still remain unknown due to their complicat... more Electron affinities (EAs) of many lanthanide elements still remain unknown due to their complicated electronic structures and relatively low EA values. In the present work, we utilized the slow-velocity map-imaging method combined with an ion trap to resolve conundrums. The EA values of praseodymium, neodymium, and terbium are determined to be 881.0(37) cm −1 or 0.109 23(46) eV, 786.3(26) cm −1 or 0.097 48(31) eV, and 1059.1(64) cm −1 or 0.131 31(79) eV, respectively. We also observed several excited states of Pr, Nd, and Tb anions.
The Journal of Chemical Physics, 2020
The latest electron affinity value of an iridium atom is 1.564 36(15) eV, determined via a method... more The latest electron affinity value of an iridium atom is 1.564 36(15) eV, determined via a method based on the Wigner threshold law by Bilodeau and co-workers. However, they observed a significant deviation from the Wigner threshold law in the threshold photodetachment experiment. To address this dilemma, we conducted high-resolution photoelectron spectroscopy of Ir- via the slow-electron velocity-map imaging method in combination with an ion trap. The electron affinity of Ir was measured to be 12 614.97(9) cm-1 or 1.564 057(11) eV. We find that the Wigner threshold law is still valid for the threshold photodetachment of Ir- through a p-wave fitting of the photodetachment channel Ir-5d86s23F4→Ir5d86sb4F9/2. The photoelectron angular distributions of photodetachment channels Ir-5d86s23F4→Ir5d76s2a4F9/2 and Ir-5d86s23F4→Ir5d86sb4F9/2 were also investigated. The behavior of anisotropy parameter β indicates a strong interaction between the two channels. Moreover, the energy level 3P2 of Ir-, which was not observed in the previous works, was experimentally determined to be 4163.24(16) cm-1 above the ground state.
Physical Review Letters, 2019
International Conference on Electronic Information Engineering, Big Data, and Computer Technology (EIBDCT 2022), May 6, 2022
The Journal of Chemical Physics
The tantalum anion has the most complicated photoelectron spectrum among all atomic anions of tra... more The tantalum anion has the most complicated photoelectron spectrum among all atomic anions of transition elements, which was the main obstacle to accurately measure its electron affinity via the generic method. The latest experimental value of the electron affinity of Ta was 0.323(12) eV, reported by Feigerle et al. [J. Chem. Phys. 74, 1580 (1981)]. In the present work, we report the high-resolution photoelectron spectroscopy of Ta− via the slow-electron velocity-map imaging method combined with a cryogenic ion trap. The electron affinity of Ta was measured to be 2652.38(17) cm−1 or 0.328 859(23) eV. Three excited states 5 D1, 3 P0, and 5 D2 of Ta− were observed, and their energy levels were determined to be 1169.64(17) cm−1 for 5 D1, 1735.9(10) cm−1 for 3 P0, and 2320.1(20) cm−1 for 5 D2 above the ground state 5 D0, respectively.
Additional file 1. The dynamic fluorescence changes of ipsilateral VPM neuronal activity during C... more Additional file 1. The dynamic fluorescence changes of ipsilateral VPM neuronal activity during CSD in awake mice. The increase in neural activity in the VPM induced by CSD showed a "propagating-like" spatial pattern that spread from the posterior-lateral to the anterior-medial side of the VPM. The left side showed the original fluorescence signal, the right side showed the relative fluorescence change.
Additional file 2. The dynamic fluorescence changes of contralateral VPM neuronal activity during... more Additional file 2. The dynamic fluorescence changes of contralateral VPM neuronal activity during CSD in awake mice. No significant activation of VGluT2 neurons was observed in the VPM after CSD induction in the contralateral cortex. The changed fluorescence signal was highly correlated with the motion of mice.
SXFEL-UF, a soft X-ray FEL user facility located in Shanghai, has been upgraded from the existing... more SXFEL-UF, a soft X-ray FEL user facility located in Shanghai, has been upgraded from the existing test facility. Electron energy increases from 840 MeV to 1.5 GeV and a SASE FEL line will be added besides the existing seeding FEL line. It has started commissioning since early this year. In order for simultaneous operation of the two FEL lines, a beam switchyard is built between the linac and the two FEL lines. In this paper, the physics design of the beam switchyard is described.
In shanghai, a hard X-ray free electron laser project named SHINE is under design. It will be bas... more In shanghai, a hard X-ray free electron laser project named SHINE is under design. It will be based on a superconducting linac running in CW mode. On the first stage, there will be three parallel undulator lines downstream the linac. For simultaneous operation of the three undulator lines, a beam distribution system based on fast kickers will be installed between linac and undulator lines. The physics design of this beam distribution system is described in this paper.
The Journal of Headache and Pain, 2022
Background As the relay centre for processing sensory information, the thalamus may involve in th... more Background As the relay centre for processing sensory information, the thalamus may involve in the abnormal sensory procedure caused by cortical spreading depression (CSD). However, few studies have focused on the transient response of thalamus during CSD. Our study aimed to investigate the neuronal activity of mouse thalamus ventral posteromedial nucleus (VPM) during CSD by in vivo micro-endoscopic fluorescence imaging of the genetic calcium probe GCaMP6s expressed in excitatory glutamatergic neurons. Methods Thirty-four transgenic VGluT2-GCaMP6s mice were used in the experiments. An endoscope was inserted into the VPM for image acquisition. CSD was induced by KCl topically applied unilaterally on the cranial dura. Data were acquired in awake (ipsilateral or contralateral VPM, saline instead of KCl, MK-801 treatment) and anaesthetized (isoflurane, pentobarbital) states. Statistical analysis was performed using analysis of variance (ANOVA) by SPSS. Results We found that after CSD in...
International Journal of Innovative Computing and Applications, 2021
The process of excavation and unloading of a deep subway foundation pit will cause deformation of... more The process of excavation and unloading of a deep subway foundation pit will cause deformation of the surrounding buildings. There are significant differences in building deformation due to different methods of supporting the foundation pit and building foundation forms. This study takes the deep foundation pit project of the station as an example to investigate this difference. A three-dimensional numerical finite element model of a deep foundation pit has been established that considers different types of building foundations (independent foundation, box foundation, and pile foundation). The sensitivity of the two supporting methods of the diaphragm wall and the combined support of isolation pile and diaphragm wall regarding the maximum settlement value of the building, the horizontal inclination value, the slope angle, and the foundation angular distortions were analyzed. Finally, the sensitivity of the length of the isolated pile to the maximum settlement value and the horizonta...
Nutrients, 2021
Inconsistent conclusions from infant sleep and feeding studies may influence parents feeding-rela... more Inconsistent conclusions from infant sleep and feeding studies may influence parents feeding-related decisions. This study aimed to systematically review the existing literature on infant sleep and its relation to the timing of introduction to complementary foods and type of milk feeding to better understand their role(s) in infant sleep. Cohort, longitudinal, cross-sectional studies, and controlled trials were identified using online searches of five databases up to April 2020. Twenty-one articles with a total of 6225 infants under 12 months-of-age were eligible. Exclusively breastfed infants (≤6 months-of-age) had a greater number of night wakings, but most studies (67%) reported no difference in night-time and 24 h sleep duration compared to formula-fed infants. However, after 6 months-of-age, most studies (>65%) reported breastfed infants to sleep less in the night-time and over 24 h compared to formula-fed infants. Furthermore, studies reported no association between the tim...
The Journal of Chemical Physics, 2021
Gold fluoride is a very unique species. In this work, we reported the resonant photodetachment sp... more Gold fluoride is a very unique species. In this work, we reported the resonant photodetachment spectra of cryogenically cooled AuF- via the slow-electron velocity-map imaging method. We determined the electron affinity of AuF to be 17 976(8) cm-1 or 2.2287(10) eV. We observed a dipole-bound state with a binding energy of 24(8) cm-1, a valence excited state with a binding energy of 1222(11) cm-1, and a resonant state with an energy of 814(12) cm-1 above the photodetachment threshold. An unusual vibrational transition with Δn = -3 was observed in the autodetachment from the dipole-bound state. Moreover, two excited states of neutral AuF were recognized for the first time, located at 13 720(78) cm-1 and 16 188(44) cm-1 above the AuF ground state.
Photonics, 2021
External seeded free-electron lasers (FELs) hold promising prospects for producing intense cohere... more External seeded free-electron lasers (FELs) hold promising prospects for producing intense coherent radiation at high harmonics of a conventional laser. The practical harmonic up-conversion efficiencies of current seeding techniques are limited by various three-dimensional effects on the electron beam. In this paper, a novel method is proposed to extend the wavelength coverage of a seeded FEL by combining the reverse taper undulator with the echo-enabled harmonic generation. The proposed technique can significantly enhance the bunching at ultra-high harmonics and preserve the electron beam qualities from degradation by deleterious effects. Theoretical analysis and numerical simulation are performed, and the results demonstrate that stable, intense, nearly fully coherent FEL pulses with photon energy up to 1 keV can be generated. The proposed technique may open up new opportunities to obtain laser-like pulses at sub-nanometer wavelength.
Arabian Journal of Geosciences, 2021
The protection of adjacent buildings is an important part of the safety control of the constructi... more The protection of adjacent buildings is an important part of the safety control of the construction of a deep foundation pit in a subway station, and a reasonable supporting method is the key to safety control. Based on the deep foundation pit project of the Nanning Metro Line 5 station in Guangxi, this paper proposes a method of combined support of the isolation pile and the diaphragm wall for the protection of buildings adjacent to the foundation pit. The three-dimensional finite element method is used to simulate the deformation law of the foundation pit adjacent to the building under the combined support during the entire excavation process, and the deformation characteristics of the isolation pile-diaphragm wall are also analyzed. The results show that compared to the diaphragm wall support method, the combined support method effectively limits the soil settlement. The maximum value of soil settlement behind the diaphragm wall is only 0.044%He (He is the excavation depth), and the position of the maximum settlement has moved to the place which far away from adjacent buildings. The maximum deformation value of the combined support method is 59.1% less than that of the diaphragm wall method, and the additional deformation of the building is controlled within 9 mm. The combined support method of isolation pile and underground diaphragm wall proposed in this paper is applied to practical engineering, and the results of field monitoring agree well with the numerical results. Therefore, it is feasible to adopt this support method for the protection of buildings adjacent to the foundation pit.
Physical Review A, 2021
Despite the fact that the laser cooling method is a well-established technique to obtain ultra-co... more Despite the fact that the laser cooling method is a well-established technique to obtain ultra-cold neutral atoms and atomic cations, it has so far never been applied to atomic anions due to the lack of suitable electric-dipole transitions. Efforts of more than a decade currently have Laas the only promising candidate for laser cooling. Our previous work [Tang et al., Phys. Rev. Lett. (2019) accept] showed that This also a potential candidate. Here we report on a combination of experimental and theoretical studies to determine the relevant transition frequencies, transition rates, and branching ratios in Th-. The resonant frequency of the laser cooling transition is determined to be /c= 4118.0 (10) cm-1. The transition rate is calculated as A=1.1710 4 s 1. The branching fraction to dark states is very small, 1.47×10-10 , thus this represents an ideal closed cycle for laser cooling. Since Th has zero nuclear spin, it is an excellent candidate to be used to sympathetically cool antiprotons in a Penning trap. The achievement of Bose-Einstein condensation, precision spectroscopy, and tests of fundamental symmetries has opened a new chapter in atomic and molecular physics. The main driving force behind this achievement is the ability to cool atoms and positive ions to K or even lower temperatures via laser cooling techniques. Although laser cooling is a well-established technique for producing ultracold neutral atoms and positive ions, it has not yet been achieved for negative ions. In principle, once we produce ultracold ensembles of a specific anion system, we can use them to sympathetically cool any anions, ranging from elementary particles to molecular anions, which will promote the research of cold plasma[1], ultracold chemistry[2], and fundamental-physics tests[3-8]. In contrast to neutral atoms and positive ions, which have an infinite number of bound states, negative ions have only a single bound state in most cases. The reason is that in atomic anions, the excess
International Journal of Innovative Computing and Applications, 2021
Quality of Life Research, 2020
Purpose Social isolation in older adults is a major public health problem and associated with inc... more Purpose Social isolation in older adults is a major public health problem and associated with increased morbidity and mortality. There are limited data on the association between social isolation and physical function including gait speed. Hence, this study is to determine the prevalence of social isolation and its association with gait speed, frailty, cognition, depression and comorbidities amongst community-dwelling older adults. Methods Social isolation, depression, frailty and perceived general health were assessed using 6-item Lubben Social Network Scale (LSNS-6), Geriatric Depression Scale (GDS), FRAIL scale and EuroQol EQ-5D-5L questionnaire which includes EQ Visual Analogue Scale (EQ-VAS), respectively. Cognition was assessed using the Chinese Mini Mental State Examination (cMMSE), while physical performance test included gait speed and short physical performance battery test. Binary logistic regression was performed to determine the influence of socio-demographic, medical, functional and cognitive variables on social isolation. Results Out of 202 participants, 27.7% were robust, 66.8% of participants were pre-frail, and 5.4% of participants were frail. Almost half (45.5%, n = 92) of the participants were found to be at risk of social isolation. A poor social network was negatively associated with mean gait speed (OR = 0.674, CI 0.464-0.979, p = 0.039), EQ-VAS (OR = 0.561, CI 0.390-0.806, p < 0.01) and cMMSE (OR = 0.630, 95% CI 0.413-0.960, p = 0.032). Conclusion Almost half of older adults in the community are at risk of social isolation with a very significant association with gait speed, cMMSE and EQ-VAS scores.
The Journal of Chemical Physics, 2020
We report the high-resolution photoelectron spectra of negative gallium anions obtained via the s... more We report the high-resolution photoelectron spectra of negative gallium anions obtained via the slow-electron velocity-map imaging method. The electron affinity of Ga is determined to be 2429.07(12) cm −1 or 0.301 166(14) eV. The fine structures of Ga are well resolved: 187.31(22) cm −1 or 23.223(27) meV for 3 P 1 and 502.70(28) cm −1 or 62.327(35) meV for 3 P 2 above the ground state 3 P 0 , respectively. The photoelectron angular distribution for photodetachment from Ga − (4s 2 4p 2 3 P 0) to Ga(4s 2 5s 2 S 1/2) is measured. An unexpected perpendicular distribution instead of an isotropic distribution is observed, which is due to a resonance near 3.3780 eV.
Physical Review A, 2020
Electron affinities (EAs) of many lanthanide elements still remain unknown due to their complicat... more Electron affinities (EAs) of many lanthanide elements still remain unknown due to their complicated electronic structures and relatively low EA values. In the present work, we utilized the slow-velocity map-imaging method combined with an ion trap to resolve conundrums. The EA values of praseodymium, neodymium, and terbium are determined to be 881.0(37) cm −1 or 0.109 23(46) eV, 786.3(26) cm −1 or 0.097 48(31) eV, and 1059.1(64) cm −1 or 0.131 31(79) eV, respectively. We also observed several excited states of Pr, Nd, and Tb anions.
The Journal of Chemical Physics, 2020
The latest electron affinity value of an iridium atom is 1.564 36(15) eV, determined via a method... more The latest electron affinity value of an iridium atom is 1.564 36(15) eV, determined via a method based on the Wigner threshold law by Bilodeau and co-workers. However, they observed a significant deviation from the Wigner threshold law in the threshold photodetachment experiment. To address this dilemma, we conducted high-resolution photoelectron spectroscopy of Ir- via the slow-electron velocity-map imaging method in combination with an ion trap. The electron affinity of Ir was measured to be 12 614.97(9) cm-1 or 1.564 057(11) eV. We find that the Wigner threshold law is still valid for the threshold photodetachment of Ir- through a p-wave fitting of the photodetachment channel Ir-5d86s23F4→Ir5d86sb4F9/2. The photoelectron angular distributions of photodetachment channels Ir-5d86s23F4→Ir5d76s2a4F9/2 and Ir-5d86s23F4→Ir5d86sb4F9/2 were also investigated. The behavior of anisotropy parameter β indicates a strong interaction between the two channels. Moreover, the energy level 3P2 of Ir-, which was not observed in the previous works, was experimentally determined to be 4163.24(16) cm-1 above the ground state.
Physical Review Letters, 2019