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[Display omitted] • Osteoclast targeted imaging-guided osteoporosis alleviation composite was designed. • The NIR excitation and emission enable deep osteoclast imaging with high resolution. • Efficient osteoporosis alleviation is achieved due to the loaded alendronate. Osteoclasts with abnormal activity play an important role in osteoporosis. Deep penetration imaging with high resolution is required for osteoclasts, while targeted drug delivery facilitates osteoporosis elimination. Here we design the persistent luminescence nanoparticles (PLNPs) with near-infrared (NIR) persistent emission at 700 nm and NIR two-photon excitation at 800–1100 nm. The NIR excitation and NIR emission realize the deep tissue imaging with high resolution. The PLNPs were then modified with D-Asp8 peptide for targeting to osteoclasts and integrated alendronate (ALN) for osteoporosis alleviation. Thus, PLNP-Asp/ALN composite realized osteoclast imaging in deep bone tissue with high sensitivity as the spot smaller than 0.74 μm was clearly observed. The results from microcomputed tomography, histochemical staining, and real-time quantitative polymerase chain analysis confirm the osteoporosis alleviation due to the integrated ALN. Thus, we design the PLNPs with NIR persistent emission and NIR excitation for interference-free deep tissue imaging and introduce ALN to eliminate osteoporosis as a new paradigm for bone-related imaging-guided therapy. [ABSTRACT FROM AUTHOR]

Heteroatom-doped hierarchical porous carbons with large specific surface area and high heteroatom content are important but they generally require multistep syntheses and harsh conditions. Herein, a scalable and straightforward strategy is introduced to synthesize N/O co-doped hierarchical porous carbons (DNKs) derived from an all-in-one phthalonitrile precursor 1,3-bis(3,4-dicyanophenoxy)benzene (DPPH) with the assistant of potassium hydroxide and urea. In this facile and template-free method, all the raw materials are placed in the tube furnace, and the one-pot process involves polymerization, carbonization and activation. At 1 bar, ultra-high CO 2 uptake of 7.27 mmol g−1 at 273 K was achieved for the sample DNK@550, which can be attribute to its well-developed micropore structure and abundant nitrogen content (7.93 wt%). Moreover, the distinct features of DNK@650 afforded a high specific capacitance of 487 F g−1 at a current density of 0.1 A g−1 in a three-electrode system using 1 M H 2 SO 4 aqueous as electrolyte. Most importantly, the fabricated symmetric supercapacitor exhibited excellent cycling stability over a new cycle record of 100000 (capacitor retention of ca. 103%). This work provides new insights for the fabrication of versatile porous carbons from readily available and flexible precursors via a facile and scalable route. Image 1 [ABSTRACT FROM AUTHOR]

This work considers various optimization aspects for the attitude synchronization of spacecraft formation. Revisiting the synchronization controllers that address unknown parameters via adaptive techniques, this work proposes a modification to the synchronization weights employed to enforce state agreement amongst the networked spacecraft. By augmenting a standard adaptive controller that accounts for unknown parameters, with adaptation of the synchronization weights, one opts to improve spacecraft synchronization. The interconnection strengths of the network nodes, responsible for enforcing synchronization amongst spacecraft, are weighted dynamically in proportion to the disagreement between the spacecraft states. Additionally, when all spacecraft are assumed identical, differing only in their orientation and initial conditions, a modification of the standard adaptive parameter laws allows to reach parameter consensus via a dynamic penalization on the pairwise differences of parameter estimates. The proposed adaptive control architecture which allows for adaptation of both parameter uncertainties and synchronization penalty terms is demonstrated via numerical studies of a four-spacecraft network with limited connectivity. As an alternative to the dynamic adjustment of the synchronization gains, a scheme is proposed to optimally select these gains. By considering the sum of deviation-from-the-mean and rotational kinetic energy as appropriate metrics for synchronization, the numerical studies provide insights into the selection of optimal edge-dependent synchronization gains when the initial conditions are assumed available. [ABSTRACT FROM AUTHOR]

This article explores the roles of on-line publications in promoting ethnic communication. Through a case study of the on-line Chinese language publications, it examines the potentials of such publications in supplementing and expanding the functions of the traditional ethnic media, strengthening cultural and communal ties of the ethnic groups, and mobilizing them for action The authors argue that in the age of cyberspace, the role of ethnic media in fortifying the cultural traits of ethnic immigrants is expected to be further strengthened. As a result, ethnic groups are more likely to be assimilated into the mainstream culture without losing their own cultural roots and ethnic identity. [ABSTRACT FROM AUTHOR]

Microgravity induces a number of significant physiological changes in the cardiovascular, nervous, immune systems, as well as the bone tissue of astronauts. Changes in cell adhesion properties are one aspect affected during long-term spaceflights in mammalian cells. Cellular adhesion behaviors can be divided into cell–cell and cell–matrix adhesion. These behaviors trigger cell–cell recognition, conjugation, migration, cytoskeletal rearrangement, and signal transduction. Cellular adhesion molecule (CAM) is a general term for macromolecules that mediate the contact and binding between cells or between cells and the extracellular matrix (ECM). In this review, we summarize the four major classes of adhesion molecules that regulate cell adhesion, including integrins, immunoglobulin superfamily (Ig-SF), cadherins, and selectin. Moreover, we discuss the effects of spaceflight and simulated microgravity on the adhesion of endothelial cells, immune cells, tumor cells, stem cells, osteoblasts, muscle cells, and other types of cells. Further studies on the effects of microgravity on cell adhesion and the corresponding physiological behaviors may help increase the safety and improve the health of astronauts in space. [ABSTRACT FROM AUTHOR]

Bone loss remains a major health concern for astronauts during space flight. Increased osteoclast activity is one of the main causes of bone loss in astronauts subjected to microgravity conditions. However, the underlying molecular mechanisms remain unclear. Microtubule actin crosslinking factor 1 (MACF1) has been implicated in the regulation of cytoskeletal distribution, cell migration, and cell differentiation. Our previous studies have shown that MACF1 promotes the differentiation of pre-osteoclasts. However, whether MACF1 regulates the migration and cytoskeletal arrangement of pre-osteoclasts under microgravity conditions has not yet been elucidated. In this study, we used a hind-limb unloading (HLU) mouse model and a random positioning machine (RPM) to simulate the effects of microgravity on pre-osteoclasts. In the HLU mouse model, the expression of MACF1 was upregulated in primary pre-osteoclasts of mice, accompanied by enhanced migration in vivo. Moreover, simulated microgravity using the RPM also promoted MACF1 expression and migration of pre-osteoclasts in vitro. Additionally, knockdown of MACF1 disrupted cytoskeletal arrangement (F-actin and microtubules) and further inhibited the migration of pre-osteoclasts via the RhoA/ROCK1 signaling pathway. We further demonstrated that knockdown of MACF1 disrupted the enhanced migration and cytoskeleton arrangement of pre-osteoclasts induced by simulated microgravity. These data demonstrate that MACF1 positively regulates the migration and cytoskeletal organization of pre-osteoclasts under simulated microgravity, suggesting that MACF1 may be a therapeutic target for the treatment of bone loss induced by microgravity. • MACF1 is a microgravity sensitive gene. • Simulated microgravity induced MACF1 expression and migration of pre-osteoclasts. • MACF1 knockdown attenuated the cytoskeleton arrangement of pre-osteoclasts. • MACF1 knockdown inhibited the migration via the RhoA/Rock1 pathway. • MACF1 knockdown prevented the migration and cytoskeleton arrangement of pre-osteoclasts induced by simulated microgravity. [ABSTRACT FROM AUTHOR]

The investigation of materials' behavior under high-temperature and high-pressure conditions, such as the correlation with structural characteristics and thermal properties, holds significant importance. However, the challenges associated with the experimental implementation have, to a certain extent, constrained such research endeavors. We utilized the ultrafast laser based non-contact thermal measurement method combined with an externally heated moissanite-anvil-cell to characterize the thermal conductivity of [10-10] oriented SiO2 crystals under high temperature (300–830 K) and high pressure (0–15 GPa) conditions. We investigated the impact of extreme conditions on the microstructure from both Raman spectroscopy and thermal perspectives. The presence of kinetic hindrances associated with the transformation of α-quartz to coesite and stishovite was identified and confirmed. It expands the comprehension and application of the SiO2 pressure–temperature phase diagram in this range and provides insights into the intricate relationship between extreme environments and material structure formation through the analysis of thermal characteristics. [ABSTRACT FROM AUTHOR]

• A bio-based intrinsic flame retardancy epoxy resin was prepared from magnolol. • It showed high thermal stability with T g > 250 °C and T d5% > 400 °C. • The system exhibited outstanding processability, very suitable for RTM process. • The system presented 'Excellent' and 'Good' in Cure and Flame Retardancy Index. • It also exhibited higher mechanical modulus and strength than DGEBA. Development of sustainable bio-based epoxy resins having better comprehensive properties than available petroleum-based epoxy resins is of paramount importance for alleviation of energy pressure and enrichment of the potent category of high-performance epoxy resins. In this study, a fully bio-based epoxy resin precursor (DGEM) was synthesized from a naturally occurring magnolol through a highly efficient one step process. The bio-based epoxy resin obtained was then cured with 4, 4′-diaminodiphenyl sulfone (DDS) and compared to the petroleum-based commercial diglycidylether of bisphenol A (DGEBA). After curing with DDS, DGEM/DDS showed higher glass transition temperature than DGEBA/DDS which was 279 °C and 231 °C, respectively. The char yield (in N 2), storage modulus and flexural modulus of the former were 1.9-fold, 47.5%, and 41.3% higher than those of the latter, respectively. Interestingly, bio-based epoxy resin of DGEM exhibited excellent processability with extremely low viscosity of 0.155 Pa·s at room temperature and a broader processing window than DGEBA/DDS as well. To exhibit such an excellent processability is very rare for high-performance epoxy resins. In addition, the cured DGEM/DDS also showed outstanding intrinsic flame retardancy, which passed the V-0 rate of UL-94 test. This study offers an opportunity to prepare bio-based epoxy resins with better properties than DGEBA and exhibits great promise in cutting-edge applications. [ABSTRACT FROM AUTHOR]

• Identified LncRNA AK039312 and AK079370 that inhibited osteoblast differentiation and bone formation. • AK039312 and AK079370 sequestered miR-199b-5p, thus inhibited osteoblast differentiation. • The combination of AK039312 and AK079370 was more drastic than AK039312 or AK079370 alone. • The mixture of si-AK039312 and si-AK079370 showed strong capability on rescuing osteoporosis. Osteoporosis caused by aging and menopause had become an emerging threat to human health. The reduction of osteoblast differentiation has been considered to be an essential cause of osteoporosis. Osteoblast differentiation could be regulated by LncRNAs, and increasing evidences have proved that LncRNAs may be adopted as potential therapeutic targets for osteoporosis. However, reports on rescue effects of LncRNAs in vivo are relatively limited. In this study, two LncRNAs (AK039312 and AK079370) were screened as osteogenic related LncRNAs. Both AK039312 and AK079370 could inhibit osteoblast differentiation and bone formation through suppressing osteogenic transcription factors. This inhibitory effect was achieved via binding and sequestering miR-199b-5p, and enhanced GSK-3β which further inhibited wnt/β-catenin pathway. Moreover, the siRNAs of AK039312 and AK079370 significantly alleviated postmenopausal osteoporosis, and the combination of si-AK039312 and si-AK079370 was more efficient than applying one si-LncRNA alone. This study has provided new insights for the therapy of osteoporosis. [ABSTRACT FROM AUTHOR]

Osteoporosis, a disease characterized by both loss of bone mass and structural deterioration of bone, is the most common reason for a broken bone among the elderly. It is known that the attenuated differentiation ability of osteogenic cells has been regarded as one of the greatest contributors to age-related bone formation reduction. However, the effects of current therapies are still unsatisfactory. In this study we identify a novel long noncoding RNA AK045490 which is correlated with osteogenic differentiation and enriched in skeletal tissues of mice. In vitro analysis of bone-derived mesenchymal stem cells (BMSCs) showed that AK045490 inhibited osteoblast differentiation. In vivo inhibition of AK045490 by its small interfering RNA rescued bone formation in ovariectomized osteoporosis mice model. Mechanistically, AK045490 inhibited the nuclear translocation of β-catenin and downregulated the expression of TCF1, LEF1, and Runx2. The results suggest that Lnc-AK045490 suppresses β-catenin/TCF1/Runx2 signaling and inhibits osteoblast differentiation and bone formation, providing a novel mechanism of osteogenic differentiation and a potential drug target for osteoporosis. [ABSTRACT FROM AUTHOR]

Osteoclasts are responsible for bone resorption and play essential roles in causing bone diseases such as osteoporosis. Microtubule actin crosslinking factor 1 (MACF1) is a large spectraplakin protein that has been implicated in regulating cytoskeletal distribution, cell migration, cell survival and cell differentiation. However, whether MACF1 regulates the differentiation of osteoclasts has not been elucidated. In this study, we found that the expression of MACF1 was increased in primary bone marrow-derived monocytes (BMMs) of osteoporotic mice and was downregulated during receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclastogenesis of pre-osteoclast cell lines RAW264.7 cells. RAW264.7 cells were transfected with shMACF1 using a lentiviral vector to study the role of MACF1 in osteoclastogenic differentiation. Knockdown of MACF1 in RAW264.7 cells inhibited the formation of multinucleated osteoclasts and decreased the expression of osteoclast-marker genes (Ctsk , Acp5 , Mmp9 and Oscar) during RANKL-induced osteoclastogenesis. Additionally, knockdown of MACF1 disrupted actin ring formation in osteoclasts and further blocked the bone resorption activity of osteoclasts by reducing the area and depth of pits. Knockdown of MACF1 had no effect on the survival of pre-osteoclasts and mature osteoclasts. We further established that knockdown of MACF1 attenuated the phosphorylation of Akt and GSK3β and inhibited the expression of its downstream target NFATc1. Akt activator rescued the inhibition of osteoclast differentiation by MACF1 knockdown. These data demonstrate that MACF1 positively regulates osteoclast differentiation via the Akt/GSK3β/NFATc1 signalling pathway, suggesting that targeting MACF1 may be a novel therapeutic approach against osteoporosis. • MACF1 knockdown inhibited RANKL-induced osteoclast differentiation and activity. • MACF1 knockdown has no effect on the survival of pre-osteoclasts and mature osteoclasts. • MACF1 knockdown attenuated the phosphorylation of Akt and GSK3β induced by RANKL. • MACF1 knockdown attenuated RANKL-induced osteoclast differentiation by regulating the Akt/GSK3β/NFATc1 signalling pathway. [ABSTRACT FROM AUTHOR]