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Abstract Dynamically evolving adhesions between cells and extracellular matrix (ECM) transmit time‐varying signals that control cytoskeletal dynamics and cell fate. Dynamic cell adhesion and ECM stiffness regulate cellular mechanosensing cooperatively, but it has not previously been possible to characterize their individual effects because of challenges with controlling these factors independently. Therefore, a DNA‐driven molecular system is developed wherein the integrin‐binding ligand RGD can be reversibly presented and removed to achieve cyclic cell attachment/detachment on substrates of defined stiffness. Using this culture system, it is discovered that cyclic adhesion accelerates F‐actin kinetics and nuclear mechanosensing in human mesenchymal stem cells (hMSCs), with the result that hysteresis can completely change how hMSCs transduce ECM stiffness. Results are dramatically different from well‐known results for mechanotransduction on static substrates, but are consistent with a mathematical model of F‐actin fragments retaining structure following loss of integrin ligation and participating in subsequent repolymerization. These findings suggest that cyclic integrin‐mediated adhesion alters the mechanosensing of ECM stiffness by hMSCs through transient, hysteretic memory that is stored in F‐actin.

As nano-aluminum powder (NAP) can improve the detonation performance of aluminum-containing explosives, more and more explosives with NAP as the metal ingredient have been studied. It is believed that the mechanical sensitivity of explosives can be significantly enhanced by the added nano-sized aluminum powder. However, the mechanism for the enhancement has not been clarified. In order to illuminate the effects of NAP on the mechanical sensitivity of explosives, two RDX-based aluminum-containing explosives with the same weight ratio and preparation process were investigated despite the aluminum powders with different nano-size and micron-size. The morphology and surface atomic ratio of the two explosives were examined by scanning electron microscopy with energy dispersive spectroscopy tests. The contact angle and other microstructures properties of the explosives were calculated by Material Studio software. Results revealed that the impact and friction activity was determined by the aluminum particle sizes and explosive components. This paper clarified the mechanism for the increase in explosives sensitivity by the addition of NAP, which provide reference for the scientific and technical design of novel explosives.

Objective: To explore the latent class characteristics of college students' mental Huagong. Methods: A questionnaire survey was carried out on 510 college students by using Collage Mental Huagong Scale(CMHGS) and the Self-assessment Scale of College Students' Innovation and Entrepreneurship Ability(CSIEASAS). Results: The college students' mental Huagong can be divided into high Huagong group (40%), high-level low will group (6%), medium-level low emotion group (48%) and low Huagong group (5%). There were significant differences in the scores of entrepreneurial personality, basic entrepreneurial ability, core entrepreneurial ability and social adaptability among the four Latent class model of collage students' mental Huagong. Conclusion: There are four Latent class model of college students' mental Huagong, and there are significant differences in each dimensions of college students' abilities of innovation and entrepreneurship among each latent class models of college students' mental Huagong. [ABSTRACT FROM AUTHOR]

The development of high performance flexible solid supercapacitors calls for an effective approach to infill gel electrolytes into porous electrodes. Here the authors report a bottom-up method to address this technical challenge, which leads to enhanced areal capacitance and durability.

AIM: To determine the impact of age on the morphology of endothelial cells and central corneal thickness (CCT) in Chinese tree shrew. METHODS: One-hundred and twenty eyes of 60 healthy Chinese tree shrews were studied. Based on age, the tree shrews were divided into four groups. After general anesthesia, the images of endothelium were acquired using non-contact specular microscope Topcon 3000P. Eight parameters of corneal endothelial cells were measured by built-in software, including CCT, endothelial cell density (ECD), percent hexagonality (HG%), coefficient of variability (CV), size of minimal cell (Smin), size of maximal cell (Smax), average cells size (Savg) and size standard deviation (Ssd). Data were analyzed using STATA software. The differences of eight parameters among groups and correlations with age were analyzed. RESULTS: In all studied animals, the average CCT was 249.6±20.29 μm (202-301 μm), ECD was 3080.72± 460.76 cells/mm2 (1239.6-4047.6 cells/mm2) and CV was 29.10±7.60 (13.6-54.6). CV was significantly different among different groups (P

AIM: To apply different doses of polygona-polysaccharose(PSP)to diabetic rats model by gastrogavage that were induced by streptozotocin(STZ), then check the rats about anterior segment, F-VEP, ERG, fundus fluorescein angiography(FFA)and measure fasting blood glucose(glucose oxidase method)by inner canthus vein blood to observe the eye disease process at different time points and to discuss the protective effect of PSP on ocular lesions in DM rats and the treatment effect, to provide the experimental basis and theoretical basis for PSP treating diabetic ocular disease. METHODS: One hundred male SD rats were randomly divided into 2 groups: diabetic model group(80 rats induced by STZ)and blank control group(20 rats). Then the diabetic model group was randomly divided into 4 subgroups. The group DM(diabetic group)had 20 rats with normal diet and 2mL physiological saline for daily gavage. PSP gavaged groups included three subgroups and with 20 rats in each group, group L(low dose of PSP gavage group, 200mg/kg), group M(medium dose of PSP gavage group, 400mg/kg), group H(high dose of PSP gavage group, 800mg/kg). Every group was gavaged with 2mL PSP. Twenty rats in group BC(blank control group), and they were gavaged saline of equal dose as control. After the success of modeling, 5 groups were under the same conditions of feeding, and gavaged every day. At 2, 4, 6, 8, 10 and 12wk, anterior segment examination and FFA were given. At 4, 8 and 12wk, F-VEP and ERG were given. Fasting blood glucose(by glucose oxidase method)was measured through inner canthus vein blood. RESULTS: Compared to BC group, fasting blood glucose levels were significantly higher in group DM, L, M and H(PPCONCLUSION: PSP can effectively reduce the blood glucose levels of diabetic rats,and also can delay the process of ocular complications in diabetic rats, which have an obvious therapeutic effect on ocular lesions. The mechanism is likely to improve the metabolism of glucose and lipid metabolism, increase the amount of glucose tolerance, and play a protective role in diabetic lens metabolism and retinal microvascular disease.

Chinese culture contains rich positive thoughts of mental transformation, mentcal Huagong (MHG: 心理化功) is the embodiment of people's quality of psychological transformation. MHG refers to the Gongfu (功夫) or mental competence that transforms negative or passive into positive or advantageous mind, which is an indispensable quality for contemporary people, especially college students, to find favorable position for the use of their abilities (用武之地) in society. In order to understand the level of college students' MHG, 586 college students from ordinary universities in Guangdong Province were tested. By item analysis and exploratory factor analysis on sample 1, confirmatory factor analysis on sample 2, college students' mental Huagong scale (CSMHGS: 大学生心理化功量表) was compiled finally. The result shows that CSMHGS is composed of 35 items and 5 factors, and the cumulative variance contribution rate is 56.145%. The result of confirmatory factor analysis shows that the 5-factor model fitted well. Cronbach α coefficient of the total scale is 0.854, and the reliability coefficient of each dimension of the scale is between 0.809~0.856. It is concluded that CSMHGS has good reliability and validity, and can be used as a measuring tool for the study of college students' MHG. [ABSTRACT FROM AUTHOR]

Metal-organic framework solids (MOFs) are synthetic porous materials that have drawn intense efforts in their synthesis and many of their chemical properties, most notably their use for the sorption of gases and vapors. The mechanical properties and mechanochemistry of MOFs, which we review in this chapter, have been only partially explored. MOFs can undergo both reversible, elastic deformations, and irreversible plastic deformations, some of which have associated mechanochemical reactions. During elastic deformation, MOFs undergo reversible structural or phase transitions. Plastic deformation of MOFs, on the other hand, can cause significant, permanent modification of the crystal structure, change in pore dimensions and configuration, and alteration of chemical bonding, all of which in turn affect their gas adsorption behavior. The large energies required to induce bond rearrangement during plastic deformation suggests an interesting potential of MOFs for shock wave mitigation applications. [ABSTRACT FROM AUTHOR]

Objectives:Asthma is a chronic inflammatory, heterogeneous airway disease affecting millions of people around the world. Curcumin has been found to have anti-inflammatory and antifibrosis effects. Researchers reported that curcumin regulated Wnt/β-catenin signaling in lots of cells. However, whether curcumin regulates the levels of Wnt/β-Catenin signaling in lung tissues and DCs (dendritic cells) remains unclear. In this study, we assessed the effects of curcumin on DCs and asthma.Methods:C57BL/6 mice immunized with OVA (ovalbumin) were challenged thrice with an aerosol of OVA every second day for 8 days. Dexamethasone or curcumin was administered intraperitoneally to OVA-immunized C57BL/6 mice on day 24 once a day for 9 days. Mice were analyzed for effects of curcumin on asthma, inflammatory cell infiltration and cytokine levels in lung tissue. DCs were isolated from mouse bone morrow. The surface markers CD40, CD86 and CD11c of DCs was detected by FACS (fluorescence activated cell sorting) and the function of DCs was detected by mixed lymphocyte reaction. The expression of GSK-3β and β-catenin was detected by Western Blot.Results:Results showed that OVA increased the number of inflammatory factors in BALF (bronchoalveolar lavage fluid), elevated lung inflammation scores in mice. Curcumin dose-dependently reversed the alterations induced by OVA in the asthmatic mice. Curcumin activated Wnt/β-catenin signaling pathway in DCs and asthmatic mouse lungs.Conclusions:Curcumin could influence the morphology and function of DCs, ease asthma symptom and inflammatory reaction through the activation of Wnt/β-catenin signaling. These results provide new evidence new evidence for application of curcumin on asthma. [ABSTRACT FROM AUTHOR]

Practical applications of metal–organic framework (MOF) materials require an in-depth understanding of their mechanical properties. We have investigated the mechanical properties and energy absorption behavior of single crystals of four isostructural UiO-type MOFs under uniaxial compression. In situ nanocompression experiments were used to measure the mechanical behavior of individual MOF nanocrystals under compression within a transmission electron microscope. The plasticity and endothermicity during deformation of MOFs shows a surprising potential for absorption and dissipation of mechanical shock. At compressive stress below 2 GPa, relatively small amounts of energy (<0.3 kJ/g) are absorbed by the compression of these MOFs. As the stress was increased, however, the energy absorption was significantly enhanced. Above 2 GPa, the energy absorption typically reaches 3–4 kJ/g; for comparison, the energy release in the explosion of TNT is ∼4 kJ/g. Gram for gram, MOFs can absorb as much energy as a high explosive can release. [ABSTRACT FROM AUTHOR]

The deformation and mechanical behavior of individual zeolitic-imidazolate framework (ZIF-8) micro- and sub-microcrystals were observed under compression. Young's modulus and volume changes as a function of applied pressure were determined on individual single crystals, offering insights in the relationship among structure, morphology, and mechanical properties. Dramatic volume decreases and amorphization were detected during compression over a pressure range of 0-4 GPa for individual 1.2 µm ZIF-8 microcrystals, and the deformed microcrystals partially recovered after pressure release. The orientation and size effects on the mechanical behavior of ZIF-8 nano- and microcrystals were also investigated. The presence of solvates within the pores of the ZIF-8 has a dramatic effect on the mechanical properties of the single crystals. Methanol-solvated ZIF-8 microcrystals are much less deformable than the desolvated microcrystals and shatter completely at very low applied force. [ABSTRACT FROM AUTHOR]

In the present study, supercritical fluid was employed to prepare a kind of supercritical fluids-decellularized dermal-based scaffold (SFDDS) from porcine dermal tissue. Further, new composite bioscaffolds containing SFDDS were designed for bioprinting applications. Then, the effect of crosslinking functionality on microstructures and thermal properties of the composite bioscaffolds containing decellularized extracellular matrix were studied. The results of thermal stability from thermogravimetric analysis and difference thermogravimetry demonstrated the structural stability of the composite bioscaffolds. A method was designed to prepare bioinspired decellularized dermal-based composite bioscaffolds, which were further characterized by infrared spectroscopy, scanning electron microscopy, and thermogravimetry analysis., Competing Interests: The authors declare no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (Copyright: © 2022 Author(s).)

Understanding the relationship between landscape ecological risk and ecosystem service value (ESV) is important for building an ecological security pattern and enhancing human well-being. Taking Fujian Province as the research area, based on the remote sensing monitoring data of land use in 1980, 2000, and 2020, we carried out a grid resampling size of 5 km × 5 km in the study area, quantitatively evaluated the landscape ecological risk and ESV, and analyzed the spatio-temporal variations. The spatial correlation between landscape ecological risk and ESV was investigated by using the bivariate spatial autocorrelation analysis and the spatial regression models. The results showed that the landscape ecological risk level in Fujian Province changed from medium level to low level, with the situation being improved. The landscape ecological risk level was generally higher in the east region and lower in the west region. ESV generally declined. The functional structure of each ecosystem was relatively stable. ESV spread from high to low with high value area as the core. There was a significant negative spatial correlation between landscape ecological risk and ESV. Landscape ecological risk had a negative effect on ecosystem total ser-vice value, with the strongest impact on the supply function.

Background: A prostatic stromal tumor is deemed to be a rare oncology condition. Based on the retrospective analysis of clinical data and scientific literature review, a case of prostatic stromal tumor was reported in this article to explore the diagnosis, treatment and prognosis of this rare disease., Case Summary: The present case involved an older male patient who was admitted to our department for a medical consultation of dysuria. Serum prostate-specific antigen was 8.30 ng/mL, Ultrasound and magnetic resonance imaging suggested evident enlargement of the prostate and multiple cystic developments internally. Considering that the patient was an elderly male with a poor health status, transurethral resection of the prostate was performed to improve the symptoms of urinary tract obstruction. Furthermore, based on histopathologic examination and immunohistochemical staining, the patient was pathologically diagnosed with prostatic stromal tumor. The patient did not receive any further adjuvant therapy following surgery leading to a clinical recommendation that the patient should be followed up on a long-term basis. However, during the recent follow-up assessment, the patient demonstrated recurrence of lower urinary tract symptoms and gross hematuria., Conclusion: Referring to scientific literature review, we believe that the management of these lesions requires a thorough assessment of the patient. Furthermore, the treatment of prostate stromal tumors should be based on the imaging examination and pathological classification. Active surgical treatment is of great significance to the prognosis of patients, and subsequent surveillance after the treatment is warranted., Competing Interests: Conflict-of-interest statement: All authors declare that they have no conflicts of interest to disclose., (©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.)