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Objective To forecast the future burden and its attributable risk factors of infective endocarditis (IE). Method We analyzed the disease burden of IE and its risk factors from 1990 to 2019 using the Global Burden of Disease 2019 database and projected the disease burden from 2020 to 2030 using a Bayesian age-period-cohort model. Results By 2030, the incidence of IE will increase uncontrollably on a global scale, with developed countries having the largest number of cases and developing countries experiencing the fastest growth. The affected population will be predominantly males, but the gender gap will narrow. The elderly in high-income countries will bear the greatest burden, with a gradual shift to middle-income countries. The incidence of IE in countries with middle/high-middle social-demographic indicators (SDI) will surpass that of high SDI countries. In China, the incidence rate and the number of IE will reach 18.07 per 100,000 and 451,596 in 2030, respectively. IE-associated deaths and heart failure will continue to impose a significant burden on society, the burden on women will increase and surpass that on men, and the elderly in high-SDI countries will bear the heaviest burden. High systolic blood pressure has become the primary risk factor for IE-related death. Conclusions This study provides comprehensive analyses of the disease burden and risk factors of IE worldwide over the next decade. The IE-associated incidence will increase in the future and the death and heart failure burden will not be appropriately controlled. Gender, age, regional, and country heterogeneity should be taken seriously to facilitate in making effective strategies for lowering the IE disease burden.

Fabricating well-aligned carbon nanotubes, especially, on a silicon substrate is very important for their applications. In this paper, an aligned carbon nanotube array has been prepared by pyrolysis of hydrocarbons catalyzed by nickel nanoparticles embedded in porous silicon (PS) templates. High-magnification transmission electron microscopy images confirm that the nanotubes are well graphitized. The PS substrates with pore sizes between 10 and 100 nm play a control role on the growth of carbon nanotubes and the diameters of the tubes increase with the enlargement of the pores of the substrates. However, such a control role cannot be found in the macro-PS substrates.

The superconductivity has been detected in the Sn-doped C60 samples by AC susceptibility measurements. The Sn-doped C60 sample is insensitive to air. EDS and XRD examinations show that the Sn-atoms have intercalated into the interstitial positions of the C60 lattice during a very slow diffusion reaction process.

The linearly polarized Cu L3-edge x-ray-absorption near-edge structure (XANES) of Bi2Sr2CaCu2O8 + delta has been measured and the spectra are interpreted by the full multiple-scattering approach in real space. The polarized spectra over a range of 20 eV can be predicted in terms of the one-electron dipole (DELTA-l = +1) transition Cu 2p --> epsilon-d, probing the unoccupied d-like (l = 2) density of states projected on the Cu site with orbital angular momentum m(l) = 0, 1 in the E parallel-to z spectra, and the m(l) = 2, 1, and 0 in the E perpendicular-to c spectra. The oscillator strength for the dipole allowed transitions (DELTA-l = -1) Cu 2p --> epsilon-s is shown to be a factor of 100 weaker than the 2p --> 3d transitions. The Coulomb interaction in the final state between the Cu 2p core hole and the excited Cu 3d electron is found to be 5.5 eV forming a bound state below the continuum threshold, the well-known Cu L3 white line. On the contrary, the core hole induces a nearly rigid redshift about 1 eV of the high-energy conduction bands.

A simple and inexpensive method for the purification of gram quantities of >99.5% pure C60 and > 98% pure C70 by a fractional crystallization process in carbon disulfide or o-xylene is described. This process is based on the finding that C60 was enriched in the solid deposit, whereas C70 was enriched in the mother liquor during crystallization of fullerenes due to differential solubilities of these two fullerenes, C60 and C70, in these solvents.

In situ DC resistance measurements were performed on semicontinuous niobium and silver films,which were made on mica and fullerene substrates in an ultra-high-vacuum chamber.Right after the interruption of the deposition,we investigated the changes (relaxation) of the sample resistance on a time scale of about 10 minutes.Resistance increase was observed for Nb/mica and Ag/C60 systems,and decrease for Ag/mica system.The relaxation is sensitive to substrate temperature and film thickness.We suggest that the edge diffusion and mergence of islands due to thermomigration of the metal atoms are responsible for the resistance relaxation.The intensity and direction of the relaxation reflect the interfacial activity of the metal/substrate system.The heterogeneities on substrate may also play an important role during this process.The analysis is presented from the angle of atom-migration and of thermodynamic evolution.

Fullerene （Ｃ６０ and Ｃ7０）films were epitaxially grown on fresh (001) mica fcc closely-packed plane parallel to the substrate surface. Metal-overlayers were deposited onto these fullerene films in an ultra-hight-vacuum(UHV) chamber and in situ resistance measurements were performed. With increasing current, we observed reversible resistance variation and irreversible breakdown. Nera the percolation threshold we find power law scaling behavior Ｉb～Ｒ－α,where Ｉb is breakdown current and R the sample resistance. The exponent α is much smaller than the values given by previous experiments and prediction of conventional Ｎｏｄｅｓ-Ｌｉｎｋｓ-Ｂｌｏｂｓ(NLB) model. Possible explanation of these phenomena based on metal-fullerene interfacial interactions is discussed.

通过在超薄金属层上蒸镀C_(68)时的电阻原位测量,发现在平均厚度约一个C_(68)单层范围内样品电阻有明显可观测的变化,主要表现为电导增强,电阻变化的程度与金属层厚度有关,最多近一个数量级。这一新的现象揭示出有可能利用宏观物理性质测量来间接研究C_(68)-金属界面相互作用,从而对常规喇曼谱和各种电子谱测量的结果给出旁证和补充。