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Polarons-fermionic charge carriers bearing a strong companion lattice deformation-exhibit a natural tendency for self-localization due to the recursive interaction between electrons and the lattice. While polarons are ubiquitous in insulators, how they evolve in transitions to metallic and superconducting states in quantum materials remains an open question. Here, we use resonant inelastic x-ray scattering to track the electron-lattice coupling in the colossal magneto-resistive bi-layer manganite La_{1.2}Sr_{1.8}Mn_{2}O_{7} across its metal-to-insulator transition. The response in the insulating high-temperature state features harmonic emissions of a dispersionless oxygen phonon at small energy transfer. Upon cooling into the metallic state, we observe a drastic redistribution of spectral weight from the region of these harmonic emissions to a broad high energy continuum. In concert with theoretical calculations, we show that this evolution implies a shift in electron-lattice coupling from static to dynamic lattice distortions that leads to a distinct polaronic ground state in the low temperature metallic phase-a dynamic polaron liquid.
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Electron quasiparticles play a crucial role in simplifying the description of many-body physics in solids with surprising success. Conventional Landau's Fermi-liquid and quasiparticle theories for high-temperature superconducting cuprates have, however, received skepticism from various angles. A path-breaking framework of electron fractionalization has been established to replace the Fermi-liquid theory for systems that show the fractional quantum Hall effect and the Mott insulating phenomena; whether it captures the essential physics of the pseudogap and superconducting phases of cuprates is still an open issue. Here, we show that excitonic excitation of optimally doped Bi2Sr2CaCu2O8+δ with energy far above the superconducting-gap energy scale, about 1 eV or even higher, is unusually enhanced by the onset of superconductivity. Our finding proves the involvement of such high-energy excitons in superconductivity. Therefore, the observed enhancement in the spectral weight of excitons imposes a crucial constraint on theories for the pseudogap and superconducting mechanisms. A simple two-component fermion model which embodies electron fractionalization in the pseudogap state provides a possible mechanism of this enhancement, pointing toward a novel route for understanding the electronic structure of superconducting cuprates.
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Objective: To describe the distribution characteristics of tea consumption in adult twins recruited in the Chinese National Twin Registry (CNTR) and provide clues to genetic and environmental influences on tea consumption. Methods: Enrolled in CNTR during 2010-2018, 25 264 twin pairs aged 18 years and above were included in subsequent analysis. Random effect models were used to estimate tea consumption in the population and regional distribution characteristics. The concordance rate of the behavior and difference in consumption volume of tea within pairs were also described. Results: The mean age of all subjects was (35.38±12.45) years old. The weekly tea consumers accounted for 17.0%, with an average tea consumption of (3.36±2.44) cups per day. The proportion of weekly tea consumers was higher among males, 50-59 years old, southern, urban, educated, and the first-born in the twin pair (P<0.05), and lower among unmarried individuals (P<0.001). Within-pair analysis showed that the concordance rate of tea consumption of monozygotic (MZ) twins was higher than that of dizygotic (DZ) twins and the overall heritability of tea consumption was 13.45% (11.38%-15.51%). Stratified by the characteristics mentioned above, only in males, the concordance rate of MZ showed a tendency to be greater than that of DZ (all P<0.05). The differences in consumption volume of tea within twin pairs were minor in MZ among males (P<0.05), while the differences were not significant in female twins. Conclusion: There were discrepancies in the distribution of tea consumption among twins of different demographic and regional characteristics. Tea consumption was mainly influenced by environmental factors and slightly influenced by genetic factors. The size of genetic factors varied with gender, age, and region, and gender was a potential modified factor.
Subject(s)
Diet , Tea , Twins, Dizygotic , Twins, Monozygotic , Adult , China , Female , Humans , Male , Middle Aged , Young AdultABSTRACT
Objective: To describe the distribution characteristics of type 2 diabetes in twins in Chinese National Twin Registry (CNTR), provide clues and evidence for revealing the influence of genetic and environmental factors for type 2 diabetes. Methods: Of all twins registered in the CNTR during 2010-2018, a total 18 855 twin pairs aged ≥30 years with complete registration information were included in the analysis. The random effect model was used to describe the population and area distribution characteristics and concordance of type 2 diabetes in twin pairs. Results: The mean age of the subjects was (42.8±10.2) years, the study subjects included 10 339 monozygotic (MZ) twin pairs and 8 516 dizygotic (DZ) twin pairs. The self-reported prevalence rate of type 2 diabetes was 2.2% in total population and there was no sighificant difference between MZ and DZ. Intra-twin pairs analysis showed that the concordance rate of type 2 diabetes was 38.2% in MZ twin pairs, and 16.0% in DZ twin pairs, the difference was statistically significant (P<0.001). The concordance rate of type 2 diabetes in MZ twin parts was higher than that in DZ twin pairs in both men and women, in different age groups and in different areas (P<0.05). Further stratified analysis showed that in northern China, only MZ twin pairs less than 60 years old were found to have a higher concordance rate of type 2 diabetes compared with DZ twin pairs (P<0.05). In southern China, the co-prevalence rate in male MZ twin pairs aged ≥60 years was still higher than that in DZ twin pairs (P<0.05). Conclusion: The twin pairs in this study had a lower self-reported prevalence of type 2 diabetes than the general population. The study results suggested that genetic factors play a role in type 2 diabetes prevalence in both men and women, in different age groups and in different areas, however, the effect might vary.
Subject(s)
Diabetes Mellitus, Type 2 , Adult , China/epidemiology , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/genetics , Diseases in Twins/genetics , Female , Humans , Male , Middle Aged , Registries , Twins, Dizygotic , Twins, Monozygotic/geneticsABSTRACT
Objective: To describe the distribution characteristics of coronary heart disease in adult twins recruited from Chinese Twin Registry (CNTR), and provide clues and evidence for the effect of genetic and environmental influences on coronary heart disease. Methods: By using the data of CNTR during 2010-2018, a total of 34 583 twin pairs aged ≥18 years who completed questionnaire survey and had related information were included in the current study to analyze the population and area distribution characteristics of coronary heart disease. Random effect models were used to compare the differences between groups. The concordane rate of coronary heart disease were calculated respectively in monozygotic (MZ) twin pairs and dizygotic (DZ) twin pairs to estimate the heritability. Results: The twin pairs included in this analysis were aged (34.2±12.4) years. The overall prevalence rate of coronary heart disease in twin pairs was 0.7%. Twin pairs who were women, older, obese and lived in northern China had higher prevalence of coronary heart disease (P<0.05). Intra-pair analysis in the same-sex twin pairs found that the concordane rate of coronary heart disease was higher in MZ twin pairs (25.3%) than in DZ twins (7.4%), and the difference was statistically significant (P<0.001). The overall heritability of coronary heart disease was 19.3% (95%CI: 11.8%-26.8%). Stratified by gender, age and area, the concordane rate was still higher in MZ twin pairs than in DZ pairs. Participants who were women, aged 18-30 years or ≥60 years and lived in northern China had a higher heritability of coronary heart disease. Conclusion: The distribution of coronary heart disease in twin pairs differed in populations and areas. The prevalence of coronary heart disease was affected by genetic factors, but the effect varied with age, gender and area.
Subject(s)
Coronary Disease , Twins, Dizygotic , Adolescent , Adult , China/epidemiology , Coronary Disease/epidemiology , Coronary Disease/genetics , Diseases in Twins/epidemiology , Diseases in Twins/genetics , Female , Humans , Male , Twins, Monozygotic/geneticsABSTRACT
We report on the development of a high-resolution and highly efficient beamline for soft X-ray resonant inelastic X-ray scattering (RIXS) located at the Taiwan Photon Source. This beamline adopts an optical design that uses an active grating monochromator (AGM) and an active grating spectrometer (AGS) to implement the energy compensation principle of grating dispersion. Active gratings are utilized to diminish defocus, coma and higher-order aberrations, as well as to decrease the slope errors caused by thermal deformation and optical polishing. The AGS is mounted on a rotatable granite platform to enable momentum-resolved RIXS measurements with scattering angles over a wide range. Several high-precision instruments developed in-house for this beamline are described briefly. The best energy resolution obtained from this AGM-AGS beamline was 12.4â meV at 530â eV, achieving a resolving power of 4.2 × 104, while the bandwidth of the incident soft X-rays was kept at 0.5â eV. To demonstrate the scientific impact of high-resolution RIXS, we present an example of momentum-resolved RIXS measurements on a high-temperature superconducting cuprate, i.e. La2-xSrxCuO4. The measurements reveal the A1g buckling phonons in superconducting cuprates, opening a new opportunity to investigate the coupling between these phonons and charge-density waves.
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An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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The search continues for nickel oxide-based materials with electronic properties similar to cuprate high-temperature superconductors1-10. The recent discovery of superconductivity in the doped infinite-layer nickelate NdNiO2 (refs. 11,12) has strengthened these efforts. Here, we use X-ray spectroscopy and density functional theory to show that the electronic structure of LaNiO2 and NdNiO2, while similar to the cuprates, includes significant distinctions. Unlike cuprates, the rare-earth spacer layer in the infinite-layer nickelate supports a weakly interacting three-dimensional 5d metallic state, which hybridizes with a quasi-two-dimensional, strongly correlated state with [Formula: see text] symmetry in the NiO2 layers. Thus, the infinite-layer nickelate can be regarded as a sibling of the rare-earth intermetallics13-15, which are well known for heavy fermion behaviour, where the NiO2 correlated layers play an analogous role to the 4f states in rare-earth heavy fermion compounds. This Kondo- or Anderson-lattice-like 'oxide-intermetallic' replaces the Mott insulator as the reference state from which superconductivity emerges upon doping.
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OBJECTIVE: To investigate the association of Toll-like receptor 4-myeloid differential protein-88- c-Jun N-terminal kinase (TLR4-MyD88-JNK) signaling pathway with inflammatory response in intracranial hemorrhage (ICH) rats and its effect on neuronal apoptosis. PATIENTS AND METHODS: The autologous blood was drawn and injected into the brain to establish the rat model of ICH (model group), and the control group was set up. The neurological behavior Longa score was given. The blood and brain tissues of rats were then collected to detect the serum indexes, including glucose (GLU), creatinine (CR), K+ and Na+, and the content of interleukin-6 (IL-6), IL-1ß and tumor necrosis factor-α (TNF-α) in each group. The neuronal apoptosis of brain tissues was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining. Moreover, the expressions of apoptosis- and TLR4-MyD88-JNK pathway-related genes and proteins were detected via Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and Western blotting. Finally, the association of TLR4-MyD88-JNK signaling pathway with the inflammatory response in ICH rats and its effect on neuronal apoptosis were completely observed. RESULTS: MiR-23b was dramatically down-regulated in CC and the low miR-23b expressions were associated with the poor prognosis and worse OS of CC patients. Additionally, the functional assays demonstrated that miR-23b overexpression obviously repressed CC cell proliferation, invasion and migration abilities through the regulation of the AKT/mTOR pathway and the epithelial-to-mesenchymal transition (EMT) progress. Moreover, the luciferase reporter assay indicated that six1 was one functional target for miR-23b in CC cells, indicating that the inhibitory functions of miR-23b in CC cells were partially regulated by six1. Moreover, miR-23b restoration could prominently repress tumor growth in vivo. CONCLUSIONS: The TLR4-MyD88-JNK signaling pathway can facilitate the inflammatory response in ICH rats, thereby promoting the neuronal apoptosis.
Subject(s)
Apoptosis/immunology , Cerebral Hemorrhage/immunology , MAP Kinase Signaling System/immunology , Neurons/pathology , Animals , Cell Proliferation , Cerebral Hemorrhage/pathology , Disease Models, Animal , Down-Regulation , Humans , MAP Kinase Signaling System/genetics , Male , Myeloid Differentiation Factor 88/metabolism , Neurons/immunology , Rats , Toll-Like Receptor 4/metabolismABSTRACT
OBJECTIVE: We aimed to compare and analyze the long-term efficacy and safety between kelp micro gelation (KMG) and gelfoam particles in partial splenic embolization (PSE). PATIENTS AND METHODS: This study retrospectively included 65 liver cirrhosis patients with comorbidity of hypersplenism who were admitted in Nanfang Hospital from July 2008 to May 2012. Among the included patients, 33 patients were in KMG-PSE group, and 32 cases were included in Gelfoam-PSE group. According to the Child-Pugh criteria, all cases were divided into grade A, B, and C, respectively. All eligible subjects received CT or MR examination and laboratory examination. RESULTS: Our results showed that both KMG and gelfoam particles could substantially improve the short-term efficacy of thrombocytopenia leukopenia. However, the efficacy of KMG is superior to that of gelfoam. Due to the characteristic of KMG as a permanent agent, KMG may result in an obvious pain in the spleen after PSE, especially in patients with megalosplenia. KMG was more expensive than gelfoam particles. The complication rate in patents with great embolization was much higher than that with less embolization. CONCLUSIONS: The efficacy of KMG is superior to that of gelfoam in both short-term and long-term. To effectively control the occurrence of severe complication, the embolization should be controlled less than 70% regardless of the embolization agents.
Subject(s)
Embolization, Therapeutic/methods , Hypersplenism/therapy , Kelp , Adult , Aged , Embolization, Therapeutic/adverse effects , Female , Gels , Humans , Liver Cirrhosis/complications , Male , Middle Aged , Retrospective Studies , Thrombocytopenia/therapyABSTRACT
We carried out temperature-dependent (20-550 K) measurements of resonant inelastic x-ray scattering on LaCoO_{3} to investigate the evolution of its electronic structure across the spin-state crossover. In combination with charge-transfer multiplet calculations, we accurately quantified the renomalized crystal-field excitation energies and spin-state populations. We show that the screening of the effective on-site Coulomb interaction of 3d electrons is orbital selective and coupled to the spin-state crossover in LaCoO_{3}. The results establish that the gradual spin-state crossover is associated with a relative change of Coulomb energy versus bandwidth, leading to a Mott-type insulator-to-metal transition.
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The first known magnetic mineral, magnetite, has unusual properties, which have fascinated mankind for centuries; it undergoes the Verwey transition around 120 K with an abrupt change in structure and electrical conductivity. The mechanism of the Verwey transition, however, remains contentious. Here we use resonant inelastic X-ray scattering over a wide temperature range across the Verwey transition to identify and separate out the magnetic excitations derived from nominal Fe2+ and Fe3+ states. Comparison of the experimental results with crystal-field multiplet calculations shows that the spin-orbital dd excitons of the Fe2+ sites arise from a tetragonal Jahn-Teller active polaronic distortion of the Fe2+O6 octahedra. These low-energy excitations, which get weakened for temperatures above 350 K but persist at least up to 550 K, are distinct from optical excitations and are best explained as magnetic polarons.
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We report the first empirical demonstration that resonant inelastic x-ray scattering (RIXS) is sensitive to collective magnetic excitations in S=1 systems by probing the Ni L_{3} edge of La_{2-x}Sr_{x}NiO_{4} (x=0, 0.33, 0.45). The magnetic excitation peak is asymmetric, indicating the presence of single and multi-spin-flip excitations. As the hole doping level is increased, the zone boundary magnon energy is suppressed at a much larger rate than that in hole doped cuprates. Based on the analysis of the orbital and charge excitations observed by RIXS, we argue that this difference is related to the orbital character of the doped holes in these two families. This work establishes RIXS as a probe of fundamental magnetic interactions in nickelates opening the way towards studies of heterostructures and ultrafast pump-probe experiments.
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Objective: To evaluate the efficacy and safety of ivabradine for the treatment of Chinese patients with chronic heart failure based on the Chinese subgroup data of the systolic heart failure treatment with the I(f) inhibitor ivabradine trial (SHIFT). Method: A total of 6 558 stable outpatients who presented symptoms of heart failure, with a left ventricular ejection fraction (LVEF) ≤35%, sinus rhythms with a heart rate ≥70 bpm participated in the randomized, double-blind, placebo-controlled, international multicenter clinical study.The subset of Chinese patients with heart rate ≥75 bpm was enrolled in the post-hoc subgroup analyses.Patients were randomly allocated by computer-generated assignment through a telephone interactive voice response system to ivabradine group (starting dose 5 mg bid, which was then uptitrated to the maximum 7.5 mg bid) or matched placebo group.The clinical baseline characteristics of participants were obtained and analyzed.The primary outcome endpoint was a composite endpoint of cardiovascular death or hospitalization resulting from worsening HF.The primary safety endpoint included total incidence of adverse events during the study, bradycardia, and adverse visual reaction (phosphenes). Results: A total of 49 Chinese centers enrolled a total of 225 patients with chronic heart failure, of whom, 106 patients were randomized to the ivabradine group and the other 119 patients to the placebo group, and the mean follow-up time was (15.6±5.1) months.By the end of the study, mean heart rate (71.0 bpm vs. 80.3 bpm, P<0.05) and incidence of the primary endpoint events (18.9% (20/106) vs. 31.9%(38/119), HR=0.56, 95%CI 0.33-0.97, P=0.039) were significantly lower, while the percentage of patients with improvement in heart functional class NYHA (53.8% (56/106) vs. 34.5% (41/119), P=0.006 1) was significantly higher in the ivabradine group than in the placebo group.The total number of adverse events (129 events, 49.6% PY) in the ivabradine group was lower than that in the placebo group (203 events, 50.8% PY). In the ivabradine group and the placebo group, there were respectively 2 patients (1.9%) and 0 patients experienced bradycardia, 3 patients (2.9%) and 1 patient (0.8%) experienced adverse visual reaction (phosphenes). Conclusions: Ivabradine significantly reduced heart rate and improved the clinical outcomes and NYHA function class in Chinese patients with chronic heart failure, these beneficial effects are achieved without inducing remarkable adverse reactions.The results of Chinese subgroup analysis were thus consistent with the overall results of the SHIFT study. Clinical Trial Registry: International standard randomized controlled trials registry, ISRCTN 70429960.
Subject(s)
Benzazepines/therapeutic use , Cardiovascular Agents/therapeutic use , Heart Failure/drug therapy , Aged , Benzazepines/adverse effects , Chronic Disease , Double-Blind Method , Female , Heart Failure, Systolic , Heart Rate , Hospitalization , Humans , Ivabradine , Male , Middle Aged , Safety , Treatment Outcome , Ventricular Function, LeftABSTRACT
Objective: To investigate the incidence of treatment-emergent central sleep apnea (TE-CSA), the characteristics of demography and the influencing factors in patients with obstructive sleep apnea syndrome (OSAS) after initial continuous positive airway pressure (CPAP) titration at high altitude. Methods: Clinical data of 297 patients with OSAS which living in plateau areas (1 000 meters or more above sea level) were retrospectively analyzed in this study from January to December, 2015. All of these patients taken an overnight CPAP titration in the Sleep Medicine Center of First People's Hospital of Yunnan Province. They were classified as with TE-CSA group and non TE-CSA group according to the outcome of CPAP titration. Comparisons of demographic characteristic, parameters of polysomnography in CPAP titration night, lung function test and blood gas analysis were made between the two groups, respectively, and statistical analysis was carried. Results: The incidence of TE-CSA was 16.5% (49/297) after initial CPAP titration at high altitude, which was higher in male patients (18.2% vs 6.8%, P=0.061). The incidence of TE-CSA decreased with the increase of age and body mass index (BMI), and the decrease of resident altitude. Multivariate Logistic regression analysis showed that the resident altitude, mixed apnea index (MAI), forced expiratory volume in 1 second (FEV(1)) and forced vital capacity (FVC) ratio, functional residual capacity (RV) and total lung capacity (TLC) ratio were the main factors affecting the occurrence of TE-CSA. Among them, the increase of resident altitude and MAI were risk factors [OR=1.16(1.02, 1.32), 1.05(1.01, 1.09)]. The increase of FEV(1)/FVC and RV/TLC were protective factors [OR=0.94(0.89, 0.98), 0.94(0.88, 0.99)]. Conclusion: The incidence of TE-CSA is high at high altitude area, and the increase of resident altitude and MAI are the risk factors for TE-CSA.
Subject(s)
Continuous Positive Airway Pressure , Sleep Apnea, Central/therapy , Altitude , China , Humans , Incidence , Male , Retrospective Studies , Sleep Apnea, ObstructiveABSTRACT
Objective:This research explores the effect of Epworth sleepiness scale (ESS) items on domestic patients. Method:Four thousand six hundred and thirty-three suspected OSAHS patients with snoring were selected from respiratory sleep center in the first people's hospital, Yunnan province, between January 2006 and December 2012. These patients filled in the ESS before PSG test. Firstly, these questionnaires were preprocessed, and the null and incorrect ones were deleted. Then, the fuzzy comprehensive evaluation was applied for the value of each item in ESS. Finally, the reliability was compared between before and after the removal of the lowest values.Result:Fuzzy comprehensive evaluation results show that the total value is 1.016, the item value of Sitting and talking to someone and In a car, while stopped for a few minutes in traffic is the lowest, which is 0.131. The result of reliability analysis shows that the value increases 0.2% after the two items being deleted.Conclusion:Some items of ESS are not suitable for Chinese patients, and they need to be deleted or modified to improve the screening efficiency.
Subject(s)
Sleep Apnea, Obstructive , Snoring , Surveys and Questionnaires , Asian People , China , Disorders of Excessive Somnolence , Humans , Psychometrics , Reproducibility of Results , Sleep Apnea, Obstructive/physiopathology , Sleep StagesABSTRACT
Resonant inelastic x-ray scattering is used to investigate the electronic origin of orbital polarization in nickelate heterostructures taking LaTiO_{3}-LaNiO_{3}-3×(LaAlO_{3}), a system with exceptionally large polarization, as a model system. We find that heterostructuring generates only minor changes in the Ni 3d orbital energy levels, contradicting the often-invoked picture in which changes in orbital energy levels generate orbital polarization. Instead, O K-edge x-ray absorption spectroscopy demonstrates that orbital polarization is caused by an anisotropic reconstruction of the oxygen ligand hole states. This provides an explanation for the limited success of theoretical predictions based on tuning orbital energy levels and implies that future theories should focus on anisotropic hybridization as the most effective means to drive large changes in electronic structure and realize novel emergent phenomena.
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Measurements of spin excitations are essential for an understanding of spin-mediated pairing for superconductivity; and resonant inelastic X-ray scattering (RIXS) provides a considerable opportunity to probe high-energy spin excitations. However, whether RIXS correctly measures the collective spin excitations of doped superconducting cuprates remains under debate. Here we demonstrate distinct Raman- and fluorescence-like RIXS excitations of Bi1.5Pb0.6Sr1.54CaCu2O(8+δ). Combining photon-energy and momentum dependent RIXS measurements with theoretical calculations using exact diagonalization provides conclusive evidence that the Raman-like RIXS excitations correspond to collective spin excitations, which are magnons in the undoped Mott insulators and evolve into paramagnons in doped superconducting compounds. In contrast, the fluorescence-like shifts are due primarily to the continuum of particle-hole excitations in the charge channel. Our results show that under the proper experimental conditions RIXS indeed can be used to probe paramagnons in doped high-Tc cuprate superconductors.