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In this review, we focus on the types of smart supramolecular gels whose self-assembly processes are affected or even triggered by physical forces including sonication and mechanical stress (mechanical force). The types of gels that are responsive to sonication and mechanical stress are examined and summarised. The gels exhibit non-covalent interactions among the gelator molecules and show dynamic and reversible properties controlled by the stimuli. Upon stimulation, the gelators cause instant and in situ gelation of organic solvents or water with different modes and outcomes of self-assembly. On the other hand, sonication and mechanical stress, as external factors, can give rise to dynamic changes in microscopic morphology, optical properties, etc. Certain thixotropic supramolecular gels exhibit perfect self-healing characteristics. The driving forces and the mechanism of the self-assembly process and the responsive outcome of morphological and spectroscopic changes are discussed. Those supramolecular gels responding to sonication and mechanical stress offer a wide range of applications in fields such as smart and adaptive materials, switches, drug control and release, and tissue engineering. [ABSTRACT FROM AUTHOR]

Thesolubility values and physicochemical properties (pH values,refractive indices, and densities) of electrolyte mixtures in quaternarysystem containing lithium, potassium, rubidium, and borate were investigatedat 348 K by isothermal dissolution method. The space phase diagram,the planar projection diagram, the water content diagram, and thediagrams of physicochemical properties depending on the compositionwere obtained using the measured data. The phase diagram of this quaternarysystem contains one invariant point, three univariant curves, andthree single salts corresponding to lithium tetraborate trihydrate(Li2B4O7·3H2O), potassiumtetraborate tetrahydrate (K2B4O5(OH)4·2H2O), and rubidium pentaborate tetrahydrate(RbB5O6(OH)4·2H2O).This quaternary system is of a simple cosaturation type, no doublesalt or solid solution formed. The scope of areas of crystallizationof salts is such that RbB5O6(OH)4·2H2O > Li2B4O7·3H2O > K2B4O5(OH)4·2H2O, which demonstrates the saltRbB5O6(OH)4·2H2Ocan be more easilyseparated from the solution than the other coexisting salts at 348K. The physicochemical properties of the solutions at equilibriumon the univariant curve CE increase obviously with increasing Jäneckeindex, J(K2B4O7);whereas on the univariant curve AE or BE, the physicochemical propertieschange slightly along with the changes of J(K2B4O7). [ABSTRACT FROM AUTHOR]

The mechanical model of a "Z" type double-decker ball bearing under the action of ra-dial load is established in this paper on the basis of the Hertz contact theoiy. According to the security contact angle theory, the influences of inner and outer bearings' internal clearances on the bearing's static load carrying capacity, radial deformation, radial stiff-ness, and load distribution of balls are analyzed. This model is verified in both stationary and rotational loading experiments. Moreover, the simulation results show that the static load carrying capacity of Z type bearing is smaller than that of either inner bearing or outer bearing that is contributed to compose the Z type bearing. The static load carrying capacity of a Z type bearing reduces with the increase of the inner and outer bearings' internal clearance. These simulation results also indicate that the contact angle of the maximum loaded ball in the outer bearing easily exceeds its security contact angle com-pared with the inner bearing, which, as the main factor, may cause the Z type bearing to overload and to fail. In this sense, the investigated Z type bearings are unfit to apply to situations with heavy load, high speed, or high precision. [ABSTRACT FROM AUTHOR]

One way to rejuvenate metallic glasses is to increase their free volume. Here, by randomly removing atoms from the glass matrix, free volume is homogeneously generated in metallic glasses, and glassy states with different degrees of rejuvenation are designed and further mechanically tested. We find that the free volume in the rejuvenated glasses can be annihilated under tensile or compressive deformation that consequently leads to structural relaxation and strain-hardening. Additionally, the deformation mechanism of highly rejuvenated metallic glasses during the uniaxial loading–unloading tensile tests is investigated, in order to provide a systematic understanding of the relaxation and strain-hardening relationship. The observed strain-hardening in the highly rejuvenated metallic glasses corresponds to stress-driven structural and residual stress relaxation during cycling deformation. Nevertheless, the rejuvenated metallic glasses relax to a more stable state but could not recover their initial as-cast state.

The metastable phase equilibria in the aqueous quaternary system LiCl KCl RbCl H2O were investigated at 298.15 K using an isothermal evaporation method. The solubilities and physicochemical properties such as the density and refractive index of the equilibrated solution were determined. On the basis of the experimental results, the stereo phase diagram, the projected phase diagram, the water content diagram, and the physicochemical properties versus composition diagrams were constructed. The projected phase diagram consists of two invariant points, five isothermal univariant curves, and four crystallization fields corresponding to single salts potassium chloride (KCl), rubidium chloride (RbCl), lithium chloride monohydrate (LiCl·H2O), and a solid solution of potassium and rubidium chloride [(K, Rb)Cl]. The two invariant points are cosaturated with three salts, which are LiCl·H2O RbCl (K, Rb)Cl and LiCl·H2O KCl (K, Rb)Cl, respectively. No double salt was formed. The crystallization region of the solid solution [(K, Rb)Cl] almost occupies the entire phase region, which shows that it is difficult to separate potassium from rubidium in chloride solution by only using evaporation and crystallization methods at 298.15 K. The calculated densities and refractive indices using empirical equations have a maximum relative error of <0.016. [ABSTRACT FROM AUTHOR]

The solubilities and physicochemical properties such as density and refractive index of the solution in the ternary systems KCl + MgCl2+ H2O and KCl + RbCl + H2O were investigated at 298.15 K using an isothermal evaporation method. The crystalloid forms of the solid phase were determined using chemical analysis and an X-ray diffraction method. On the basis of experimental data, the metastable equilibrium phase diagrams and the physicochemical properties vs composition in the ternary systems at 298.15 K were constructed. In the metastable phase diagram of the ternary system KCl + MgCl2+ H2O at 298.15 K, there are two invariant points, three univariant curves, and three crystallization fields corresponding to potassium chloride (KCl), magnesium chloride hexahydrate (MgCl2·6H2O), and a double salt carnallite (KCl·MgCl2·6H2O). In the metastable phase diagram of the ternary system KCl + RbCl + H2O, there are two invariant points and three crystallization fields corresponding to the single salts potassium chloride (KCl), rubidium chloride (RbCl), and a solid solution of potassium and rubidium chloride [(K, Rb)Cl]. Comparisons between the metastable phase diagrams at 298.15 K and at 323.15 K show that the crystallization forms have not changed, while the crystallization zones have slight changes. The calculated densities and refractive indices using an empirical equation have the maximum relative error < 0.016. [ABSTRACT FROM AUTHOR]

Two simple fluorescent anion receptors based on 1-phenyl-3-methylpyrozole-5-one-4-one phenylhydrazone (L1) and 1-phenyl-3-methylpyrozole-5-one-4-one p-nitrophenylhydrazone (L2) were designed, synthesized and characterized with ¹H NMR, COSY spectrum, 13C NMR, ESI-mass and elemental analyse. Interestingly, two receptors with similar configuration exhibited different anion binding behaviors in DMSO solution. The results of Job plots and ESI-mass spectrum indicate that L1 bind anions such as F-, AcO-, H2PO4- to form 2:1 host-guest complexation, while L2 bind anions to form 1:1 host-guest complexation in the solution. [ABSTRACT FROM AUTHOR]

Abstract  When one or more nitro groups are incorporated into an anion receptor, intramolecular proton transfer from nearby –NH groups often takes place and is a significant obstacle for the construction of supramolecular systems. In this paper, by employing an intramolecular hydrogen bond between –NH and nitro groups in order to reduce the acidity of the amide group, we were able to construct a receptor that formed stable supramolecular systems. The receptor forms a 1:2 supramolecular compound with fluoride, whereas 1:1 complexes were formed with AcO− and H2PO4 − in DMSO solution. Using this system, an easy-to-prepare test paper for the detection of F− in low concentration at (10−4 M) in water was developed. [ABSTRACT FROM AUTHOR]

Metallic glass composites with shape memory crystals show enhanced plasticity and work-hardening capability. We investigate the influence of various critical structural aspects such as, the density of crystalline precipitates, their distribution and size, and the structural features and intrinsic properties of the phase on the deformation behavior of metallic amorphous Cu 64 Zr 36 composites with B2 CuZr inclusions using molecular dynamics simulations. We find that a low density of small B2 inclusions with spacing smaller than the critical shear band length controls the formation and distribution of plastic zones in the composite and hinders the formation of critical shear bands. When the free path for shearing allows the formation of mature shear bands a high volume fraction of large B2 precipitates is necessary to stabilize the shear flow and avoid runaway instability. Additionally, we also investigate the deformation mechanism of composites with pure copper crystals for comparison, in order to understand the superior mechanical properties of metallic glass composites with shape memory crystals in more detail. The complex and competing mechanisms of deformation occurring in shape memory metallic glass composites allow this class of materials to sustain large tensile deformation, even though only a low-volume fraction of crystalline inclusions is present.

Composite structures with bends are widely used in aerospace and industrial sectors. However health monitoring of such structures is challenging due to their complex topographical features. Recent literature shows that bends in composite laminates can confine and guide ultrasonic energy along their length, known as feature-guided waves (FGW). This article demonstrates a fiber Bragg grating based technique using FGW modes for defect detection and identification in bent composite laminates. In addition, the effects of defect depth and excitation frequency on the FGW mode reflection coefficient are reported using 3D finite element simulations. Physical insight into the reflection behavior is discussed based on an analysis of mode interaction with part-thickness cracks. [ABSTRACT FROM AUTHOR]

Flexible and stretchable electronics are rapidly evolving to be used in a wide range of applications, including wearable medical devices, implantable health monitoring devices, and bio-integrated systems. As an important method to integrate heterogeneous materials and functional components toward flexible and stretchable electronic systems, transfer printing technology has attracted increasing attention. Among the different approaches in transfer printing, electromagnetic-assisted transfer printing provides a versatile method that allows remote control. In order to investigate the effects of various materials and geometric parameters on the electromagnetic-assisted transfer printing process, a theoretical analysis is combined with the finite element method to investigate the underlying physics. The desirable ranges of parameters (e.g. thickness, radius, and elastic modulus of the upper and lower films in the design) are obtained for the optimized operation. The results indicate that the radii of the upper and lower films should be selected with large values and their upper limits are bound by the size of the functional components to be transferred. Moreover, the radii ratio between the upper to lower film should be within the range of 0.6–0.9. Though small thickness and elastic modulus are preferred in the upper and lower films, the values should be sufficiently large to ensure the strength. Meanwhile, the thickness ratio of upper to lower film should be within the range of 0.5–2. At the same time, the elastic modulus ratio and the height of the lower pickup cavity are shown to have little influence on the maximum displacement of the lower film. With the theoretical predictions validated by the finite element analysis, the results presented in this study are expected to provide useful guidelines for the experimental design. [ABSTRACT FROM AUTHOR]

In the multi-view video coding, both temporal and interview redundancies can be exploited by using standard block-based motion estimation technique. This paper describes a novel Bio-inspired neural networks model to enhance regions and extract contours of image for block-based motion estimation. We implements the optimized algorithm in the reference model of H.264 compiled by VC6.0, and chooses six typical video sequences for simulation comparison. Experiments performed show the good visual results which can reduces the computational complexity in a certain degree and enhances encoding efficiency with few changes in the reconstructed image quality and bit rate.

Structural health monitoring (SHM) using ultrasonic guided waves has proven to be attractive for the identification of damage in composite plate-like structures, due to its realization of both significant propagation distances and reasonable sensitivity to defects. However, topographical features such as bends, lap joints, and bonded stiffeners are often encountered in these structures, and they are susceptible to various types of defects as a consequence of stress concentration and cyclic loading during the service life. Therefore, the health condition of such features has to be assessed effectively to ensure the safe operation of the entire structure. This paper proposes a novel feature guided wave (FGW) based SHM strategy, in which proper FGWs are exploited as a screening tool to rapidly interrogate the representative stiffener-adhesive bond-composite skin assembly. An array of sensors permanently attached to the vicinity of the feature is used to capture scattered waves from the localized damage occurring in the bond line. This technique is combined with an imaging approach, and the damage reconstruction is achieved by the synthetic focusing algorithm using these scattered signals. The proposed SHM scheme is implemented in both the 3D finite element simulation and the experiment, and the results are in good agreement, demonstrating the feasibility of such SHM strategy. [ABSTRACT FROM AUTHOR]

In order to study the effects of different functional strains on alleviating protein oxidation and enhancing flavor in fermented sausage, Lactiplantibacillus plantarum NJAU-01 (LpN), with excellent antioxidant activity, L. plantarum CGMCC 18217 (Lp10), with the ability to improve the flavor of fermented sausage, and Staphylococcus saprophytic CGMCC 3475 (Ss), with high protease activity, were selected for use in a multi-strain starter culture for fermented sausage. The degree of protein degradation and oxidation in fermented sausage during fermentation and the final flavor of the product were evaluated. The results showed that the Lp10 + LpN + Ss starter culture could reduce the degree of protein oxidation in fermented sausage and increase the types and contents of volatile flavor substances, while endowing fermented sausage with better color and improving its texture characteristics, and the fermented product had high sensory scores. This study showed that the combination of Lp10, LpN and Ss could improve the quality and flavor of fermented sausage while delaying the oxidation of protein.

In order to accurately link the entity references in the commander’s demand statement to the standardized entity nodes in the knowledge graph, an entity linking method in the military domain based on improved edit distance is proposed. By summarizing the non-standard forms of entity referencing to establish an index, and using the BM25 model to integrate the improved edit distance algorithm that considers the character position exchange, inclusion similarity and other similarities, the entities to be linked are sorted to achieve the link. The experimental results show that the entity linking method in the military field can effectively improve the matching accuracy in similarity calculation.

Part II. Discusses robotics in education. Creation of a learning environment where students can explore the design area; Introduction of children to technology; Use of robotics projects in cross-discipline courses.

Auto-eliminating clearance auxiliary bearing devices (ACABD) can automatically eliminate the protective clearance between the ball bearing's outer race and the ACABD's supports, thus recenter the rotor when active magnetic bearing (AMB) system fails. This paper introduces the mechanical structure and working principles of the ACABD. When the rotor drops, numerical and experimental studies on the transient responses of the rotor and the ACABD's supports are also conducted as follows. First, we propose an equivalent clearance circle method to establish dynamic models of rotor dropping on the ACABD. Based on these models, the rotor dropping simulations are carried out to investigate the modes of lubrication and the ACABD's support shape's influences on the performance and execution time of clearance elimination. Second, various AMB rotor dropping tests are performed on our experimental setup with different ACABD supporting conditions. Indicated from the basically consistent simulation and experimental results, the correctness of the theoretical analysis and the successful operation of ACABD have been verified. Moreover, with the grease lubrication in the ball bearing and convex shape supports, the ACABD can eliminate the protective clearance within approximately 0.5 s upon the rotor drops and then sustain the rotor to operate stably around its original rotation center. Because of clearance elimination, the dramatic impact between the ball bearing and the supports is avoided and the impact forces among each part are effectively reduced. Meanwhile, the possibility of incurring full-clearance backward whirling motion is eliminated. [ABSTRACT FROM AUTHOR]

• Esketamine injection 0 h but not 6 h after reactivation facilitates NOR memory performance. • Esketamine injection 24 h after sampling without reactivation did not facilitate NOR memory performance. • NBQX block the improving effect of esketamine on memory reconsolidation. Esketamine, the right-handed optical isomer of racemic ketamine, is a rapidly acting antidepressant approved by the FDA for treatment-resistant depression in 2019. However, few studies have investigated esketamine's role in learning and memory, particularly in the context of memory reconsolidation. Herein, we evaluated esketamine's role in memory reconsolidation in 7-week-old male Institute of Cancer Research mice subjected to the novel object recognition (NOR) memory task. The NOR reconsolidation procedure comprised three phases: sampling, reactivation, and testing. Esketamine-enhanced NOR memory performance when injected into mice 0 h after reactivation rather than following a 6 h delay. Conversely, administering esketamine 24 h after sampling without reactivation did not enhance NOR memory performance. Notably, esketamine exhibited no discernible effects on nonspecific responses, such as locomotor activity and exploratory behavior. Furthermore, the α -amino-3‑hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA)-type receptor antagonist NBQX effectively blocked the esketamine-induced enhancement of memory reconsolidation. In conclusion, esketamine treatment markedly improves memory reconsolidation in NOR tasks, and this effect is linked to AMPA receptor activity. [ABSTRACT FROM AUTHOR]

Background: Currently, most researchers mainly analyzed coronavirus disease 2019 (COVID-19) pneumonia visually or qualitatively, probably somewhat time-consuming and not precise enough., Purpose: This study aimed to excavate more information, such as differences in distribution, density, and severity of pneumonia lesions between males and females in a specific age group using artificial intelligence (AI)-based computed tomography (CT) metrics. Besides, these metrics were incorporated into a clinical regression model to predict the short-term outcome., Materials and Methods: The clinical, laboratory information and a series of HRCT images from 49 patients, aged from 20 to 50 years and confirmed with COVID-19, were collected. The volumes and percentages of infection (POIs) among bilateral lungs and each bronchopulmonary segment were extracted using uAI-Discover-NCP software (version R001). The POI in three HU ranges (i.e., <-300, -300-49, and ≥50 HU representing ground-glass opacity [GGO], mixed opacity, and consolidation) were also extracted. Hospital stay was predicted with several POI after adjusting days from illness onset to admission, leucocytes, lymphocytes, C-reactive protein, age, and gender using a multiple linear regression model. A total of 91 patients aged 20-50 from public database were selected., Results: Right lower lobes had the highest POI, followed by left lower lobes, right upper lobes, middle lobes, and left upper lobes. The distributions in lung lobes and segments were different between the sexes. Men had a higher total POI and GGO of the lungs, but less consolidation than women in initial CT (all p < 0.05). The total POI, percentage of consolidation on initial CT, and changed POI were positively correlated with hospital stay in the model. A total of 91 patients aged 20-50 years in the public database were selected, and AI segmentation was performed. The POI of the lower lobes was obviously higher than that in the upper lobes; the POI of each segment of the right upper lobe in the males was higher than that in the females, which was consistent with the result of the 49 patients previously., Conclusion: Both men and women had characteristic distributions in lung lobes and bronchopulmonary segments. AI-based CT quantitative metrics can provide more precise information regarding lesion distribution and severity to predict clinical outcome., (© 2022 American Association of Physicists in Medicine.)