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Abstract Population mobility is a key component in promoting the re-agglomeration and dissemination of social and economic factors. Based on Spring Festival data from 2019 to 2023 on Baidu Migration Big Data, this paper analyses the spatiotemporal patterns and structural characteristics of population mobility in cities across China through spatiotemporal statistics and social network analysis and investigates the evolution patterns of Chinese population migration behavior under the influence of COVID-19 epidemic during Spring Festival. The results of the study show that: (1) There are significant temporal and spatial differences in the impact of COVID-19 on population migration, with much stronger shocks on the cities of middle migration scale; (2) Population migration in Chinese cities is robust, and the impact of COVID-19 on population movement and community evolution is mainly manifested in short-term effects, with essentially no residual effects; (3) Between 2020 and 2023, a total of 119 cities experience a transfer of communities (32.25%), of which 69 cities transfer once, 20 cities transfer twice, and 30 cities transfer three times. In addition, it is found that the closeness of urban links based on population movements remains subject to geospatial effects, and the boundaries of “communities” coincide very closely with provincial borders. The results of this study have important theoretical and practical implications for a deeper understanding of the long-term impact of major public health events on changes in the geographical characteristics of population distribution and the structure of population mobility networks.

Population mobility is a key component in promoting the re-agglomeration and dissemination of social and economic factors. Based on Spring Festival data from 2019 to 2023 on Baidu Migration Big Data, this paper analyses the spatiotemporal patterns and structural characteristics of population mobility in cities across China through spatiotemporal statistics and social network analysis and investigates the evolution patterns of Chinese population migration behavior under the influence of COVID-19 epidemic during Spring Festival. The results of the study show that: (1) There are significant temporal and spatial differences in the impact of COVID-19 on population migration, with much stronger shocks on the cities of middle migration scale; (2) Population migration in Chinese cities is robust, and the impact of COVID-19 on population movement and community evolution is mainly manifested in short-term effects, with essentially no residual effects; (3) Between 2020 and 2023, a total of 119 cities experience a transfer of communities (32.25%), of which 69 cities transfer once, 20 cities transfer twice, and 30 cities transfer three times. In addition, it is found that the closeness of urban links based on population movements remains subject to geospatial effects, and the boundaries of "communities" coincide very closely with provincial borders. The results of this study have important theoretical and practical implications for a deeper understanding of the long-term impact of major public health events on changes in the geographical characteristics of population distribution and the structure of population mobility networks. [ABSTRACT FROM AUTHOR]

Almost fully stripped Fe ions accelerated up to 0.9 GeV are demonstrated with a 200 TW femtosecond high-intensity laser irradiating a micron-thick Al foil with Fe impurity on the surface. An energetic low-emittance high-density beam of heavy ions with a large charge-to-mass ratio can be obtained, which is useful for many applications, such as a compact radio isotope source in combination with conventional technology. [ABSTRACT FROM AUTHOR]

In this paper, a new modular active power filtering approach is proposed to eliminate harmonic currents and compensate reactive power. The method for identifying reference currents is based on FMVs “multi-variable filter” .This method uses two (FMVs) having the advantage of extracting harmonic directly from the αβ axis, the first FMV (FMV Current) extracts the fundamental and individual harmonic component of the distorted line current signal and injects equal-but-opposite of each harmonic current into the line using a voltage source inverter VSI dedicated to that specific harmonic and the second FMV (FMV Voltage) estimates the fundamental component of the line voltage. Moreover the dc-side voltage is controlled by a fuzzy logic controller. The new approach has been illustrated in order to find the best way to reduce network harmonic currents and reactive power compensating of the connected load. All of the studies have been carried out through detail digital dynamic simulation using the MATLAB/Simulink Power System Toolbox. [ABSTRACT FROM AUTHOR]

The evaluated single-particle energies of neutron states were obtained for doubly magic neutronrich nucleus Ni. The evaluations were made by extrapolation of the experimental energies of stable nickel isotopes based on the mass regularities in the results of theoretical calculations of the energies, in particular, using the Koura-Yamada potential. The evaluated energies were analyzed by the mean-field model with dispersive optical potential; a good agreement between the calculated and evaluated energies was achieved. [ABSTRACT FROM AUTHOR]

Experimental single-particle energies and occupation probabilities for neutron states near the Fermi energy in 58,60,62,64Ni nuclei were obtained from joint evaluation of the data on nucleon stripping and pickup reactions on the same nucleus. Degeneracy of the 2 p3/2,1/2 and 1 f5/2 subshells was demonstrated. The resulting data were analyzed within a mean-field model with dispersive optical-model potential. Good agreement was obtained between the calculated and experimental single-particle energies of the subshells. [ABSTRACT FROM AUTHOR]

Single-particle energies corresponding to the maximum value of the spectroscopic factor were obtained for the proton states near the Fermi energy in the 58,60,62,64Ni nuclei by the joint evaluation of the data on the stripping and pickup reactions on the same nucleus. These results are compared with the center-of-gravity energies of the single-particle state fragment distributions obtained by the same method and with the single-particle energies calculated with the potential of X. Koura and M. Yamada and with the dispersive optical model potential. The single-particle state fragmentation effect is discussed. [ABSTRACT FROM AUTHOR]

Production and decay of the isotope 271Ds were studied. The isotope was produced by 208Pb + 64Ni → 271Ds + n reaction. Fourteen α-decay chains have been assigned to decays originating from the isotope 271Ds. An excitation function of the production of this isotope was measured. The results have provided a good confirmation of production and decay of 271Ds reported by Hofmann et al. The presence of an isomeric state in 271Ds has been confirmed. The existence of a possible isomeric state in 267Hs is presented. [ABSTRACT FROM AUTHOR]

A theoretical study of β decay and delayed neutron has been carried out with a global β-decay model, the gross theory. The gross theory is based on a consideration of the sum rule of the β-strength function, and gives reasonable results of β-decay rates and delayed neutron in the entire nuclear mass region. In a fissioning nucleus, neutrons are produced by β decay of neutron-rich fission fragments from actinides known as delayed neutrons. The average number of delayed neutrons is estimated based on the sum of the β-delayed neutron-emission probabilities multiplied by the cumulative fission yield for each nucleus. Such a behavior is important to manipulate nuclear reactors, and when we adopt some new high-burn-up reactors, properties of minor actinides will play an important roll in the system, but these data have not been sufficient. We re-analyze and improve the gross theory. For example, we considered the parity of neutrons and protons at the Fermi surface, and treat a suppression for the allowed transitions in the framework of the gross theory. By using the improved gross theory, underestimated half-lives in the neutron-rich indium isotopes and neighboring region increase, and consequently follow experimental trend. The ability of reproduction (and also prediction) of the β-decay rates, delayed-neutron emission probabilities is discussed. With this work, we have described the development of a programming code of the gross theory of β-decay including the improved parts. After preparation finished, this code can be released for the nuclear data community.

A comprehensive approach to determine nuclear data of unstable nuclei will be described. It consists of a measurement of fission and capture cross sections, mass distribution of fission fragments (independent fission yields) and number of prompt fission neutrons by the method of surrogate reactions. A multi-dimensional Langevin model is being developed to estimate the independent fission yields theoretically. Furthermore, the β decay properties of the fission fragments, almost all are neutron-rich unstable nuclei, are investigated systematically by improving the gross theory of β decay, which will yield information on the decay heat and delayed-neutron data

Abstract Aim and Methods We investigated the association between polymorphisms of the angiotensin converting enzyme-1 (ACE-1) and angiotensin II type one receptor (AT1RA1166C) genes and the causation of renal disease in 76 advanced chronic kidney disease (CKD) pediatric patients undergoing maintenance hemodialysis (MHD) or conservative treatment (CT). Serum ACE activity and creatine kinase-MB fraction (CK-MB) were measured in all groups. Left ventricular mass index (LVMI) was calculated according to echocardiographic measurements. Seventy healthy controls were also genotyped. Results The differences of D allele and DI genotype of ACE were found significant between MHD group and the controls (p = 0.0001). ACE-activity and LVMI were higher in MHD, while CK-MB was higher in CT patients than in all other groups. The combined genotype DD v/s ID+II comparison validated that DD genotype was a high risk genotype for hypertension .~89% of the DD CKD patients were found hypertensive in comparison to ~ 61% of patients of non DD genotype(p = 0.02). The MHD group showed an increased frequency of the C allele and CC genotype of the AT1RA1166C polymorphism (P = 0.0001). On multiple linear regression analysis, C-allele was independently associated with hypertension (P = 0.04). Conclusion ACE DD and AT1R A/C genotypes implicated possible roles in the hypertensive state and in renal damage among children with ESRD. This result might be useful in planning therapeutic strategies for individual patients.

The article discusses the results of a study about the effects of sugar malabsorption of the effectiveness of standard glucose-based and reduced-osmolarity maltodextrin (MD)-based oral rehydration solutions (ORS). Boys with noncholera diarrhea and moderate dehydration were randomly assigned to either standard ORS or MD-ORS. Children given with standard ORS develop osmotic diarrhea due to the combined effect of transient sugar malabsorption and slight hypertonicity of the ORS. Reduced-osmolarity glucose-based ORS is found to be superior to both standard and reduced-osmolarity solutions.

A gas-filled recoil separator GARIS was installed at the RIKEN Linear Accelerator facility. Using the separator, two reactions, 208Pb(64Ni, 1n), and 209Bi(64Ni, 1n), were investigated. In the first reaction we observed fourteen α-decay chains which were assigned to be the decays starting from the isotope 271Ds(Z=110). The α-decay energies as well as the decay times coincided well with the values reported by GSI group. Existence of an isomeric state in 271Ds became clear from the present work. In the second reaction we have observed 14 α-decay chains that can be assigned to subsequent decays from 272111. The present result is the first clear confirmation for the discovery of 272111 and its α-decay products, 264Bh and 268Mt, reported previously by a GSI group. New information on their half-lives and decay energies is presented. [Copyright &y& Elsevier]

The masses of the exotic isotopes 210-214Ac and 210-214Ra have been measured with a multireflection time-of-flight mass spectrograph. These isotopes were obtained in flight as fusion-evaporation products behind the gas-filled recoil ion separator GARIS-II at RIKEN. The new direct mass measurements serve as an independent and direct benchmark for existing α-γ spectroscopy data in this mass region. Further, new mass anchor points are set for U and Np nuclei close to the N=126 shell closure for a future benchmark of the Z=92 subshell for neutron-deficient heavy isotopes. Our mass results are in general in good agreement with the previously indirectly determined mass values. Together with the measurement data, reasons for possible mass ambiguities from decay-data links between ground states are discussed. [ABSTRACT FROM AUTHOR]

Using a multireflection time-of-flight mass spectrograph located after a gas cell coupled with the gas-filled recoil ion separator GARIS-II, the masses of several a-decaying heavy nuclei were directly and precisely measured. The nuclei were produced via fusion-evaporation reactions and separated from projectilelike and targetlike particles using GARIS-II before being stopped in a helium-filled gas cell. Time-of-flight spectra for three isobar chains, 204Fr-204Rn-204At-204Po, 205Fr-205Rn-205At-205Po-205Bi, and 206Fr-206Rn-206At, were observed. Precision atomic mass values were determined for 204-206Fr, 204,205Rn, and 204,205At. Identifications of 205Bi, 204,205Po, 206Rn, and 206At were made with N≲10 detected ions, representing the next step toward use of mass spectrometry to identify exceedingly low-yield species such as superheavy elemention [ABSTRACT FROM AUTHOR]