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Uncertainties about the efficacy of influenza vaccination for populations with heart failure (HF) in preventing cardiovascular outcomes, as well as lack of effective vaccination strategies, may contribute to low vaccine coverage rate (VCR) in China and globally. We assessed the feasibility of a strategy to promote influenza vaccines in patients hospitalized with acute HF in China and to inform the design of a hybrid effectiveness-implementation cluster randomized trial to evaluate this strategy on mortality and hospital re-admission. We conducted a cluster randomized pilot trial involving 11 hospitals in Henan Province in China, with mixed-methods evaluation between December 2020 and April 2021. A process evaluation involved interviews with 51 key informants (patients, health professionals, policy makers). The intervention included education about influenza vaccination and availability of free vaccines administered prior to hospital discharge for HF patients, while usual care included attending community-based points of vaccination (PoV) for screening and vaccination. Implementation outcomes focused on reach, fidelity, adoption, and acceptability. Recruitment rates were assessed for trial feasibility. Effectiveness outcomes were influenza VCR, HF-specific rehospitalizations and mortality at 90 days. A total of 518 HF patients were recruited from 7 intervention and 4 usual care hospitals (mean of 45 participants per hospital per month). VCR was 89.9% (311/346, 86.1-92.8%) in the intervention group and 0.6% (1/172, 0.0-3.7%) in the control group. The process evaluation demonstrated reach to patients with lower socioeconomic and education status. There was good fidelity of the intervention components, with education and PoV set up processes being adapted to local hospital workflow and workforce capacity. Intervention was acceptable and adopted by patients and health professionals. However, outside of a trial setting, concerns were raised around vaccination reimbursement costs, workforce accountability and capacity. The intervention strategy appears feasible and acceptable for improving VCR in HF patients at county-level hospitals in China. Trial registration: This pilot trial is registered with the acronym PANDA II Pilot (Population Assessment of Influenza and Disease Activity) at ChiCTR.org.cn (ChiCTR2000039081).

Achieving subwavelength optical focusing is of great importance in nanophotonics. However, achieving focusing with both a small focal spot size and a large focal length remains elusive so far. Here, a large focal length planar focusing device is presented, utilizing highly oriented Dyakonov polaritons in hyperbolic metamaterial with periodic silver rings as the excitation source. Experimental results show that by controlling the size of the excitation sources, the focal length can reach 6 λ 0 (where λ 0 is the illumination wavelength), and the focal spot size can be reduced to λ 0 /10. This method provides new prospects for planar polariton optical applications. [ABSTRACT FROM AUTHOR]

In order to clarify the reasons for the emergence of problems such as high machining difficulty and poor machining surface quality encountered in the machining process of SiCp/Al composites, this paper presents a simulation study of the deformation mechanism occurring during the cutting process of SiCp/Al (SiC particle-reinforced Al matrix composites) by using the molecular dynamics (MD) method. The mechanism of strengthening and hardening occurring during cutting of SiCp/Al composites is discussed in terms of the slip expansion of dislocations and the interaction between different types of dislocations. It is found that the presence of SiC balls hinders the slip and expansion of dislocations in the Al (aluminum) matrix, resulting in the strengthening of the Al matrix between the SiC (silicon carbide) balls, mainly because the dislocations in the workpiece interact with each other during the cutting process to form dislocation tangles, stacking layer dislocations and dislocation locks, which hinder the slip and expansion of dislocations and thus increase the strength of the Al matrix. By analyzing the stress distribution inside the workpiece during the cutting process, it is found that the stress inside the workpiece is mainly concentrated in the area where the tool flank face is in contact with the workpiece, which is the main reason for the occurrence of working hardening in SiCp/Al composites. [ABSTRACT FROM AUTHOR]

In this paper, the Johnson-Cook constitutive model is modified by considering the influence of hard point such as TiC and NbC in the matrix of Inconel718 on the deformation stress. The theoretical model of cutting specific energy in the main deformation zone of Inconel718 is modified based on the new constitutive model by combining the strain gradient theory. The effect of different cutting parameters on cutting specific energy is studied, and the effect of cutting specific energy on cutting deformation and the resulting dimensional effect are also analyzed. The research results show that cutting specific energy increases with the increase of cutting speed. With the increase of cutting thickness, the cutting specific energy reduced, and the trend is non-linear. The change of undeformed chip thickness will cause size effect. The cutting specific energy increases with the reduction of the thickness of undeformed chip, and the impact of the thickness of undeformed chip on the cutting specific energy becomes smaller and smaller as the speed increases. The existence of hard points makes the main deformation zone generate a large amount of heat energy and deformation energy, which leads to dimensional effects and makes the material be more prone to adiabatic shear instability, then leads to the increase of cutting specific energy. With the increase of cutting specific energy, the width of adiabatic shear band is narrowed, the degree of serration is aggravated, and the chip morphology is closer to the experimental results. [ABSTRACT FROM AUTHOR]

Using a photocatalyst to convert solar energy into energy that can be used directly is a research direction in renewable clean energy. At present, in the field of photocatalysis, g-C3N4 is an important energy material for hydrogen and oxygen production by hydrolyzing. To further improve the photocatalysis effect of g-C3N4, chemical doping modification is an efficient improvement method. The Co element, due to its unique d-state, has played an outstanding role in changing the photocatalytic performance of graphitic carbon nitride (g-C3N4), but its doping position and modification contribution are still unclear. In this article, CASTEP first principle software is used to calculate the N position in g-C3N4 substituted by Co atom. By analyzing the density of states of Co atom, C atom and N atom in each doping position, it is found that the band gap in Co2 doping position decreases the most and the structure is the most stable, which can effectively prevent the recombination of photo-generated carriers and improve the photocatalytic performance better. The relationship between the solar absorption of Co2-g-C3N4 and the distance between the electron center and hole center has been explained from the point of view of electron hole distribution. The present study can provide a new idea for the optimization and design of advanced energy materials. [ABSTRACT FROM AUTHOR]

The interface bonding mechanism between Ti3Al0.125Cr0.875 N coating and WC carbide tool is calculated and analyzed based on the first-principles calculations in this paper. The Ti3Al0.125Cr0.875 N(010) (Cr)/WC (100) interface structure is the most stable interface model by calculating the adhesion work, interface energy and fracture toughness of the interface structure. When subjected to external forces, cracks tend to appear in the matrix, which has a certain protection effect on the interface joint. Furthermore, the bonding nature and bonding characteristics at the interface are further explained from the perspective of electronic structure. A new Cr-C bond is formed at the interface, and the bond length is 1.832 nm, which is smaller than other bond lengths in the interface structure, making the interface more stable. It provides theoretical basis for the research of carbide tool interface in future. [ABSTRACT FROM AUTHOR]