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Optically levitated oscillators in high vacuum have excellent environmental isolation and low mass compared with conventional solid-state sensors, which makes them suitable for ultrasensitive force detection. The force resolution usually scales with the measurement bandwidth, which represents the ultimate detection capability of the system under ideal conditions if sufficient time is provided for measurement. However, considering the stability of a real system, a method based on the Allan variance is more reliable to evaluate the actual force detection performance. In this study, a levitated optomechanical system with a force detection sensitivity of 6.33 ± 1.62 zN/Hz1/2 was demonstrated. And for the first time, the Allan variance was introduced to evaluate the system stability due to the force sensitivity fluctuations. The force detection resolution of 166.40 ± 55.48 yN was reached at the optimal measurement time of 2751 s. The system demonstrated in this work has the best force detection performance in both sensitivity and resolution that have been reported so far for optically levitated particles. The reported high-sensitivity force detection system is an excellent candidate for the exploration of new physics such as fifth force searching, high-frequency gravitational waves detection, dark matter research and so on.

In order to study the improvement effect of nano-clay and polypropylene fiber on the mechanical properties of recycled aggregates, unconfined compression tests and triaxial shear tests were conducted. The experimental results show that adding polypropylene fibers to recycled aggregates increases the unconfined compressive strength by 27% and significantly improves ductility. We added 6% nano-clay to fiber-reinforced recycled aggregates, which increased the unconfined compressive strength of the recycled aggregates by 49% and the residual stress by 146%. However, the ductility decreased. Under low confining pressures, with the addition of nano-clay, the peak deviatoric stress strength of the fiber-reinforced recycled aggregates first decreased and then increased. When the nano-clay content was 8%, this reached a maximum value. However, under high confining pressures, the recycled aggregate particles were tightly interlocked, so that the improvement effect of the fiber and nano-clay was not obvious. As more nano-clay was added, the friction angle of the fiber-reinforced recycled aggregates decreased, while the cohesion increased. When the content of nano-clay was 8%, the cohesive force increased by 110%. The results of this research indicate that adding both polypropylene fibers and nano-clay to recycled aggregates has a better improvement effect on their strength characteristics than adding only polypropylene fibers. This study can provide a reference for improving the mechanical properties of recycled aggregates and the use of roadbeds.

In order to study the influence of nano-MgO on the strength characteristics of cement-reinforced waste road recycled aggregate (CRA), the California bearing ratio (CBR) test, unconfined compressive strength (UCS) test, scanning electron microscope (SEM) test, X-ray energy dispersive spectroscopy (EDS) test and X-ray diffraction (XRD) test were carried out. In the test of using nano-MgO modified cement-reinforced waste road recycled aggregates (MCRA), the cement content was fixed at 4 %, considering the two ages of 7 d and 28 d and the four types of nano-MgO content. The mechanical test results show that the addition of nano-MgO has a certain effect of improving mechanical properties; The CBR values of MCRA specimens with nano-MgO all meet the requirements of extremely heavy and extremely heavy traffic levels of expressways and first-class highways; The unconfined compressive strength of 0.4 %MCRA can meet the heavy traffic grade requirements of expressways and first-class highways; 0.4 % is the optimum dosage of nano-MgO; The bivariate quadratic polynomial mathematical models of CBR value and unconfined compressive strength of MCRA specimens with nano-MgO content and age were established by curve fitting, and the fitting effect was ideal. Finally, the microscopic test was used to further analyze the internal mechanism of nano-MgO enhancing the strength of CRA.

Abstract Background Spinal artery ischemia (SCI) events can result from over coverage of the descending thoracic aorta with a coated stent during Thoracic Endovascular Aortic Repair (TEVAR). The aim of this study was to determine whether a new distal perforating stent could reduce the incidence of spinal cord ischemia while remodeling the true lumen. Methods TBAD patients treated with Talos stent in the vascular surgery Department of Yan 'an Hospital affiliated to Kunming Medical University between December 2017 and October 2019 were retrospectively analyzed to investigate the short-term safety and effectiveness of Talos stent. Results A total of the 20 patients, including 14 males and 6 females, with an average age of 52.65 ± 8.98 years (range 37–68 years), were included in the analysis. Stent-grafts were successfully implanted in all patients under local anesthesia, with a technical success rate of 100%. The average operation time was 50.75 ± 13.01 min. A total of 2 cases (10%) presented chest pain associated with intercostal artery ischemia that was relieved on the 3rd and 5th postoperative day, respectively. Postoperative mean follow-up was 16.15 ± 3.99 months. No paraplegia or other complications occurred. And stenting did not induce new tears. No migration, deformation, or fracture of the stents occurred. There was a significant difference in the remolding of the true lumen preoperatively and at 12 months postoperatively (P

In recent years, expanded polystyrene (EPS) lightweight soil has been widely used as subgrade in soft soil areas because of its light weight and environmental protection. This study aimed to investigate the dynamic characteristics of sodium silicate modified lime and fly ash treated EPS lightweight soil (SLS) under cyclic loading. The effects of EPS particles on the dynamic elastic modulus (Ed) and damping ratio (λ) of SLS were determined through dynamic triaxial tests at various confining pressures (σ3), amplitudes, and cycle times. Mathematical models of the Ed of the SLS, cycle times, and σ3 were established. The results revealed that the EPS particle content played a decisive role in the Ed and λ of the SLS. The Ed of the SLS decreased with an increase in the EPS particle content (EC). The Ed decreased by 60% in the 1–1.5% range of the EC. The existing forms of lime fly ash soil and EPS particles in the SLS changed from parallel to series. With an increase in σ3 and amplitude, the Ed of the SLS gradually decreased, the λ generally decreased, and the λ variation range was within 0.5%. With an increase in the number of cycles, the Ed of the SLS decreased. The Ed value and the number of cycles satisfied the power function relationship. Additionally, it can be found from the test results that 0.5% to 1% was the best EPS content for SLS in this work. In addition, the dynamic elastic modulus prediction model established in this study can better describe the varying trend of the dynamic elastic modulus of SLS under different σ3 values and load cycles, thereby providing a theoretical reference for the application of SLS in practical road engineering.

Nowadays, many studies have been established to develop strategies for inflammatory bowel disease (IBD) treatment. However, seldom of them explored the synergistic effects of materials and probiotics in IBD treatment. Herein, we prepared probiotics-loaded dietary fiber microspheres and studied their potential in IBD therapy. The carrageenan, a typical dietary fiber, was functionalized with polymerizable groups and employed to fabricate the methylacrylylated carrageenan hydrogel microspheres (CHMSs) by microfluidics. The CHMSs loaded with probiotics exhibited good monodispersity, biocompatibility, and the best effects in relieving the symptoms of IBD and body weight recovery than other groups, indicating the probiotics and carrageenan have synergistic effect for IBD treatment. These results show the huge potential of the probiotics-loaded CHMSs for IBD therapy.

Diatomite is a non-metallic mineral resource rich in SiO2, which can be used to modify coastal cement soil. In order to explore the mechanical modification effect of diatomite on coastal cement soil at the age of 7 days, based on coastal cement soil with cement content of 5% (mass fraction), diatomite of 0%, 5%, 10%, 15% and 20% (mass fraction) was mixed for modification. Through the unconfined compressive strength test, the triaxial unconsolidated undrained test, backscattered electron imaging (BSE), and energy-dispersive spectroscopy (EDS) technology, the influence of diatomite content and confining pressure on the peak strength of modified coastal cement soil was explored. The empirical formula between the peak strength of the DE specimen and the content of diatomite and confining pressure was established by curve fitting, and the fitting effect was ideal. When diatomite was mixed with coastal cement soil, the optimal dosage of diatomite was 5% from the perspective of mechanical properties and economic benefits of the maximum growth rate of compression and shear. The unconfined compressive strength test showed that the peak strength and elastic modulus of the modified coastal cement soil with 5% diatomite content were 37% and 57% higher than those of cement soil, respectively. The triaxial unconsolidated undrained test showed that the internal friction angle of the modified coastal cement soil was stable at about 30°, and cohesion of DE-5, DE-10, DE-15, and DE-20 increased by 28%, 48%, 78%, and 97%, respectively, compared to cement soil. The microscopic test found that the pore distribution of modified coastal cement soil is closely related to the strength change. The results show that the addition of diatomite can effectively improve the mechanical properties of soil-cement.

In order to study the mechanical modification effect of nano-MgO on cement-reinforced recycled fine aggregate (CRA), direct shear tests and triaxial shear tests were carried out. In the test of recycled fine aggregate reinforced by nano-MgO modified cement (MCRA), the cement content was fixed at 2%, and the nano-MgO content varied between 0%, 0.5%, 1.0%, 1.5% and 2.0%. The test results showed that adding nano-MgO can greatly increase both the direct shear strength and triaxial shear strength of MCRA. This increase in direct shear strength was mainly attributed to the increase in cohesion. However, this increase in triaxial shear strength was attributed to the simultaneous increase in the cohesion and friction angle.

Recently, the non-fullerene acceptors with fused rings enable high-efficiency organic solar cells but they are not ideal in terms of synthetic cost and yield. Here, Huang et al. report ‘less fused’ acceptors with non-covalent S⋅⋅⋅O interactions and solar cell efficiency of up to 13%.

Using polypropylene fiber (PPF) and nano clay modified lime treated soil (LS), the static and dynamic properties of fiber modified lime treated soil (FLS), nano clay modified lime treated soil (NLS), and fiber nano clay composite modified lime treated soil (NFLS) were studied. Through the unconfined compressive strength (UCS) test and dynamic triaxial test of FLS, NLS, and NFLS, the static and dynamic elastic modulus characteristics at 7 day curing age were explored, and the damage stress–strain model was established. The results show that: (1) Polypropylene fiber and nano clay can significantly enhance the mechanical properties of NFLS. Nano clay can promote the reaction between lime and soil to produce calcium silicate hydrate (C-S-H) and calcium aluminate hydrate (C-A-H), thus improving the strength of NFLS, and UCS can be increased by up to 103%. Polypropylene fiber can enhance the ductility of NFLS and increase the residual ductility strength, and the residual strength can be increased by 827%. (2) Nano clay can enhance the static and dynamic elastic modulus of modified lime treated soil. The static and dynamic elastic modulus of NLS, FLS, and NFLS are linear with the change of polypropylene fiber and nano clay content. The static and dynamic elastic modulus of NLS, FLS, and NFLS are linear, exponential, and logarithmic, respectively. (3) The mesoscopic random damage model can characterize the stress–strain relationship of NFLS. Polypropylene fiber and nano clay can improve the ductility and strength of modified LS, and the composite addition of polypropylene fiber and nano clay can improve the ability of modified LS to resist damage.

The design of the coating architecture plays an important role in improving the mechanical performance of the hard coating. In present work, several novel multilayered diamond/β-SiC composite architectures were deposited on cemented tungsten carbide substrates by hot filament chemical vapor deposition. Field emission scanning electron microscope (FE-SEM) observation reveals periodic multilayered configurations with diamond/β-SiC composite layers and microcrystalline diamond (MCD) or nanocrystalline diamond (NCD) layers. Moreover, Rockwell indentation, scratch and nano-indentation tests indicate that multilayered diamond/β-SiC composite and MCD coating possess not only good adhesion (52.9 ± 0.5 N) and crack propagation resistance, but also high hardness (83.6 ± 3.5 GPa) and modulus (856.1 ± 87.5 GPa) among all as-deposited coatings. For this configuration, the hardness of the coating is inherited from the MCD layer, while the low residual stress, enhanced adhesion and crack propagation resistance are due to the composite coating and multilayer architecture. Thus, the mechanical properties of diamond coating are improved by the innovative diamond/β-SiC composite multilayer, which provides a potential approach for high-performance diamond coated cutting tools. Keywords: Diamond/β-SiC, Composite, Multilayer, Adhesion, Hardness

This data contains additional data related to the article “Influence of Substrate Temperature on the Film Morphology and Photovoltaic Performance of Non-fullerene Organic Solar Cells” (Jicheng Zhang et al., In press) [1]. Data include measurement and characterization instruments and condition, detail condition to fabricate norfullerene solar cell devices, hole-only and electron-only devices. Detail condition about how to control the film morphology of devices via tuning the temperature of substrates was also displayed. More information and more convincing data about the change of film morphology for active layers fabricated from different temperature, which is attached to the research article of “Influence of Substrate Temperature on the Film Morphology and Photovoltaic Performance of Non-fullerene Organic Solar Cells” was given.

Previous studies have shown that prior knowledge can have both enhancing and detrimental effects on memory for relevant information. Few studies have explored the boundary conditions under which prior knowledge facilitates or interferes with memory processes. In addition, to what extent the effects of prior knowledge change over time is unclear. In this study, we addressed this question by separating category familiarity (i.e., prior conceptual knowledge) and stimulus familiarity at different retention intervals. Participants were tested with a recognition task after they learned four types of words, that is., familiar words from familiar categories (FwordFcate) and unfamiliar categories (FwordUcate) as well as unfamiliar words from familiar (UwordFcate) and unfamiliar categories (UwordUcate). The results showed a significant interaction between category familiarity and word familiarity, that is, unfamiliar words, but not familiar words, from familiar categories were remembered better than those from unfamiliar categories. The enhancing effect of category familiarity depended on the recollection process and remained stable over time. This study suggested that stimulus familiarity modulates the effects of category familiarity on memory performance, and clarified the boundary conditions for the effects of prior knowledge.

Shear-type structures are common structural forms in industrial and civil buildings, such as concrete and steel frame structures. Fault diagnosis of shear-type structures is an important topic to ensure the normal use of structures. The main drawback of existing damage assessment methods is that they require accurate structural finite element models for damage assessment. However, for many shear-type structures, it is difficult to obtain accurate FEM. In order to avoid finite element modeling, a model-free method for diagnosing shear structure defects is developed in this paper. This method only needs to measure a few low-order vibration modes of the structure. The proposed defect diagnosis method is divided into two stages. In the first stage, the location of defects in the structure is determined based on the difference between the virtual displacements derived from the dynamic flexibility matrices before and after damage. In the second stage, damage severity is evaluated based on an improved frequency sensitivity equation. The main innovations of this method lie in two aspects. The first innovation is the development of a virtual displacement difference method for determining the location of damage in the shear structure. The second is to improve the existing frequency sensitivity equation to calculate the damage degree without constructing the finite element model. This method has been verified on a numerical example of a 22-story shear frame structure and an experimental example of a three-story steel shear structure. Based on numerical analysis and experimental data validation, it is shown that this method only needs to use the low-order modes of structural vibration to diagnose the defect location and damage degree, and does not require finite element modeling. The proposed method should be a very simple and practical defect diagnosis technique in engineering practice. [ABSTRACT FROM AUTHOR]