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The efficacy of surgical intervention in ameliorating long-term prognosis for moderate volume of cerebral hemorrhage in the thalamus-internal capsule region remains unsubstantiated by clinical investigations. Consequently, the acquisition of credible evidence is imperative to authenticate the effectiveness of these methodologies. One hundred and three eligible patients with moderate-volume thalamus-internal capsule region cerebral hemorrhage. Twenty-seven pairs of successful matches after using the 1:1 propensity score matching method, totaling 54 patients, were analyzed. The short- and long-term treatment outcomes of patients in the stereotactic surgery and conservative treatment groups were compared. The prognosis of the 2 groups of patients was analyzed by logistic regression analysis and model comparison. The primary outcome of this study was to assess the assessment of daily living scores after 6 months of treatment. Based on the analysis of this study, the assessment of daily living of the surgical group were significantly higher than those of the conservative treatment group after 6 months of treatment (P < 0.001), and the difference was statistically significant. The amount of residual hematoma was significantly lower in the stereotactic surgery group than in the conservative treatment group at 3 days, 7 days, and 2 weeks after the onset of the disease (P < 0.001), and the complication rate was lower than the conservative treatment group (P < 0.05). Univariate logistic regression showed that the risk of severe neurological dysfunction for patients in the surgery group was (odds ratio -0.27, 95% confidence interval: 0.08–0.86, P < 0.05). In multivariate logistic regression analysis, the odds ratio was 0.29 (95% confidence interval: 0.09–0.96, P < 0.05) after adjusting for all covariates. For moderate-volume thalamus-internal capsule region cerebral hemorrhage, stereotactic paracentesis has the advantage of a shorter hospital stay and a lower complication rate than conservative treatment. Moreover, it yields superior outcomes in terms of daily living assessment scores after six months of treatment and enhanced neurological recovery. [ABSTRACT FROM AUTHOR]

• A multi-scale indentation model (MSI) for the stiff film-compliant substrate structures is established. • Two dimensionless numbers g /(E s −1/3 E f 1/3 t f) and τ 0 /(E s 2/3 E f 1/3 t f) are proposed to evaluate the indentation size effect. • The predicted bending stiffness by the MSI model is consistent with the experimental results. As critical components or platforms, stiff film-compliant substrate structures are widely used in micro-electro-mechanical systems (MEMS) and other devices, in which their indentation behavior plays an important role. In this work, a multi-scale indentation model (MSI) for stiff film-compliant substrate structures is established based on the strain gradient theory and the surface elastic model. With this model, the indentation size effect of the structure is investigated from three aspects: the load-depth relationship, the distribution of bending moments in the film, and the surface morphology. The results show that the indentation size effect is mainly caused by the characteristic length and the surface residual stress of the film, and it is sensitive to the modulus ratio of the film to the substrate but has little relation with Poisson's ratio and the contact radius. Based on the above analysis, two dimensionless numbers are proposed to evaluate the indentation size effect of stiff film-compliant substrate structures. Besides, the predicted bending stiffness by the theoretical model is consistent with the experimental result, which verifies the effectiveness of the MSI model. Our research sheds light on the understanding of the indentation size effect of stiff film-compliant substrate structures and provides theoretical guidance for the design of related devices. [ABSTRACT FROM AUTHOR]

To enrich the output performances and application fields of friction inertial piezoelectric actuators, a multi-mode friction inertial piezoelectric actuator was proposed. It had three driving modes, i.e. the inertial stick-slip mode, the inertial impact mode and the compound driving mode. An integrated flexible mechanism (IFM) consisting of the lever-shaped flexible mechanism (LSFM) and the butterfly-shaped flexible mechanism (BSFM) was designed for achieving these three driving modes. Theoretical analysis of the IFM was performed by using the matrix-based compliance modeling method and the response surface methodology. An experimental system was established to test the output performances of the actuator under various driving modes. Experimental results indicated that the actuator in three driving modes presented different output performances, and the output displacement in the compound driving mode was equivalent to the sum of those in the two single inertial modes. In the compound driving mode, the actuator achieved larger step displacement, and it also achieved good speed, loading capacity as well as motion stability. For instance, the maximum speed was 10.04 mm/s at 250 Hz in the compound driving mode, while they were 5.06 mm/s at 250 Hz in the inertial impact mode and 10.81 mm/s at 450 Hz in the inertial stick-slip mode. Furthermore, output performances of the actuator could be easily tuned in the compound driving mode when two driving voltages were controlled separately, which provided an idea for achieving the linear smooth motion. • A multi-mode friction inertial piezoelectric actuator was proposed. • Output performances of the actuator under various driving modes were characterized. • Better output performances were achieved under the compound driving mode. • The linear smooth motion was realized under the compound driving mode. [ABSTRACT FROM AUTHOR]

The stiff film/compliant substrate composite structure with a high modulus ratio finds a wide range of applications in production and in scientific research, and its indentation behavior cannot be described by the traditional theory when the film thickness is reduced from the millimeter scale to the micrometer or nanometer scale. In order to better understand the trans-scale indentation response of the composite structure caused by the reduction in the film thickness, this problem is solved analytically with the strain gradient theory and integral transformation. The gradient effect on the indentation response of the system is assessed in detailed from three aspects: load-displacement relationship, surface topography and distribution of bending moment on the film. In addition, the influences of film thickness, modulus ratio of the film to the substrate, contact radius and Poisson's ratio on the gradient effect are investigated. It is found that the gradient effect on the indentation response of the system, which is not sensitive to the contact radius and Poisson's ratio, is related not only to the film thickness but also to the modulus ratio of the film to the substrate. Based on the above analysis, a dimensionless number (g/ l) is proposed to evaluate the gradient effect on the indentation behaviors of the system. And with the help of the dimensionless number, a new simple and accurate method for measuring the material length scale is proposed. Our research provides a theoretical basis for an in-depth understanding of the gradient effects on the indentation response of the stiff film/compliant substrate system and for the measurement of the material length scale. [ABSTRACT FROM AUTHOR]

Occurrences of perfluoroalkyl and polyfluoroalkyl substances (PFASs) in tree bark from four species were investigated. Species-dependent congener distribution patterns were firstly reported for perfluorocarboxylic acids (PFCAs) and perfluoroalkyl sulfonic acids (PFSAs). The majority of PFSAs and PFCAs in Chinese red pine bark were C5–C7 PFSAs and perfluorohexanoic acid (PFHxA, containing six carbon atoms, C6), whereas perfluorobutanesulfonic acid (PFBS, C4) and longer chain congeners (PFCAs: C ≥ 7; PFSAs: C ≥ 8) took a larger proportion in the fissured bark from Canadian poplar, Chinese scholartree and weeping willow. The species-dependent congener profiles depended on the structures and chemical compositions of tree bark, as well as the translocation of PFASs within plants. Different tree bark characteristics caused different retention abilities for particle-bound and gaseous PFASs. Particle-bound PFASs retained in the rougher structures of fissured bark led to preferential retention of long chain congeners (the major fraction in the particle phase), while lipid-rich Chinese red pine bark retained more gaseous PFASs (mainly short chain congeners). Besides, the abundance of short chain PFASs in red pine bark was consistent with the chain length-dependent translocation behaviors of PFASs in various plants, suggesting that translocation of PFASs within plants to tree bark may be invovled. Unlabelled Image • Species-dependent bark accumulation of PFASs was firstly observed and explored. • Gaseous diffusion and plant translocation contributed to more short chain PFASs occurring in Chinese red pine bark. • Particle entrapment was responsible for preferential accumulation of long chain PFASs in fissure bark. [ABSTRACT FROM AUTHOR]

Size effects and thermal effects together determine the microscale plastic response of metallic structures in high-integrated microelectromechanical systems (MEMS) at different temperatures. To investigate the microscale plastic behavior of metallic materials at different temperatures, a thermo-mechanical coupled microscale plasticity model is developed. In the mechanical part of this model, the framework of conventional plasticity theory is maintained, and the plastic strain gradient is introduced as an internal variable to increase the tangential hardening modulus without the introduction of higher-order stress and higher-order boundary conditions. The influence of temperature on the mechanical parameters (e.g. the yield strength) is calibrated by experiment results. In the thermal part of this model, the heat generation in the plastic deformation stage is calculated by the difference between the plastic work and the hardening stored energy influenced by the plastic strain gradient. Due to the strong nonlinearity of the coupled equations, a finite element solution algorithm that combines the radial return method and the staggered solution scheme is proposed. The effectiveness of this model and its solution algorithm is verified by comparisons with the experiment results and a numerical benchmark example. Finally, taking the tensile behavior of a plate with a hole in its center as an example, the coupling effect of strain gradient strengthening and thermal softening on the microscale plastic behavior of metallic materials is investigated. The results show that the microscale plastic behavior of metallic materials at high temperatures depends on the competition between thermal softening and strain gradient strengthening. Our study provides a theoretical basis and a reliable simulation method for the design of MEMS at different temperatures. • A new thermo-mechanical coupled microscale plasticity model that accounts for the size effect and the thermal effect is developed; • The finite element solution algorithm combining the radial return method and the staggered solution scheme for this model is proposed. • The effectiveness of this model and its solution algorithm is verified by comparisons with the experiment results. • The plastic behavior of microscale metallic materials at high temperatures depends on the competition between thermal softening and strain gradient strengthening. [ABSTRACT FROM AUTHOR]

We report a white organic light-emitting diode (WOLED) of simple construction with a bi-component emitting layer, in which a novel, dual-role deep blue TADF emitter as both the non-doped blue emitter and efficient host of an orange TADF emitter of TXO-TPA. The deep blue molecule (SDPS-4PhCz, CIE y ∼ 0.04) was designed using spiro-diphenylsulfone (SDPS) as electron-accepting group and four 9-phenyl-9H-carbazole (N-PhCz) as the electron-donating groups. SDPS-4PhCz showed delayed fluorescence with short delayed lifetime of 1.4 μs via fast reverse intersystem crossing (RISC) from "hot exciton" triplet excited state. The solution-processed, non-doped deep blue inverted OLED device exhibited a maximum EQE of 4.92% with low efficiency roll-off. The two-color WOLED with extremely simple device architecture showed an EQE above 17%, CIE (0.39, 0.44) and high CRI of 64 by spin-coating method. Image 1 • A new deep blue emitter via a spiro concept was designed. • The non-doped deep blue OLED showed a low efficiency roll-off. • The fast RISC process in SDPS-4PhCz coincided with "hot exciton" mechanism. • The two-color WOLED showed an EQE above 17% by spin-coating method. [ABSTRACT FROM AUTHOR]

Highlights • A theoretical indentation model applicable to film/substrate systems with large modulus ratios (E f /E s = 102–105) is established. • A new convenient method for measuring the modulus of nanofilm with limited thickness by indentation on hard film/soft substrate system is proposed. • Compared with the free-standing indentation test or bulge test, this method is more convenient and cheaper. • The effectiveness of the model and method was verified by experiments and simulations. Abstract Two-dimensional (2D) materials have received extensive attention due to their excellent physical and chemical properties, whose mechanical properties play critical roles in their applications. In this paper, a new convenient method for measuring the modulus of nanofilm by indentation on hard film/soft substrate system is proposed. In order to verify the correctness of the new method, the graphene oxide (GO) nanofilm deposited on polydimethylsiloxane (PDMS) is tested. The modulus of the GO nanofilm is measured as 60.39 ± 7.82 GPa, which is consistent with the modulus measured by previous researches. Finally, the finite element method (FEM) is used to investigate the effectiveness of the new method and to evaluate its error sensitivity to the indenter size, film radius, and the surface roughness. The results show that this method can accurately measure the modulus of nanofilm through the indentation response of the hard film/soft substrate system. Compared with the free-standing indentation test, the method proposed by us eliminates the disadvantages of boundary adhesion and has the advantages of simple sample preparation, easy operation, and high success rate. [ABSTRACT FROM AUTHOR]

The tool properties of grinding wheels can vary in a wide range due to the variety of processes. The properties, in turn, affect the grinding process and the grinding results. Understanding the interdependencies from the initial manufacturing to the final grinding results is the key to achieve the target-oriented generation of the grinding wheel properties for the grinding task at hand. This paper presents a novel approach to model the interdependencies between the manufacturing of bronze-bonded grinding wheels and the resulting grinding behaviour. The manufacturing steps are described with sub models in order to forecast properties and application behaviour. [ABSTRACT FROM AUTHOR]

Two spiro-D configured host materials DCPSO and DAPSO bearing electron-withdrawing group spironaphthalenone and electron-donating group phenylcarbazole or triphenylamine were designed and synthesized. The spironaphthalenone moiety was embedded in the host skeleton such that the host materials have twisted conformation and separated molecular frontier orbitals. The triplet energy of the DCPSO and DAPSO were estimated to be 2.60 and 2.45 eV, respectively, rendering them suitable host materials for red organic light-emitting diodes (OLEDs). The single-carrier transporting devices revealed that DCPSO is a bipolar material with more balanced hole and electron flux in the emitting layer than that of DAPSO . Employing DCPSO as host, high external quantum efficiencies of 16.6% and 13.3% as well as negligible efficiency roll-off were achieved for red phosphorescent and red TADF OLEDs. [ABSTRACT FROM AUTHOR]

Plant-based milk is considered a healthy and environmentally sustainable option. In order to solve the physical and chemical instability problem of most plant milk and increase the chance of consumer acceptance of the flavor, this experiment used soybean as raw material, fructo-oligosaccharides (FOS) as prebiotics, and added kombucha for fermentation. The microbial composition, functional components, antioxidant capacity, physicochemical properties and flavor relationship of fermented soy milk at different fermentation times (up to 96 h) were studied by high-throughput sequencing, laser confocal scanning imaging, and gas chromatography−mass spectrometry. According to the results, the synbiotic interaction of FOS and kombucha consortium promoted the growth of yeast and lactic acid bacteria in soy milk. The ideal fermentation time was 84 h. At this time, fermented soy milk added with FOS displayed increased β-glucosidase activity (by 68.10 mU/mL), isoflavones mainly represented by genistein content (by 612.41%), and DPPH radical scavenging activity (by 25.02%). Furthermore, the addition of FOS intensified the sour taste of the 84 h-fermented soy milk. The content of hexanal was reduced, while favorable flavor substances, such as citric acid and linalool, were also produced. Soymilk fermented with kombucha and FOS provides an opportunity to explore the physical and chemical characteristics and the mechanism of flavor formation in multi-strain co-fermentation systems and to develop commercial plant-based fermentation products. [ABSTRACT FROM AUTHOR]