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The impairment of angiogenesis is an outstanding pathogenic characteristic of glucocorticoid (GC)-induced osteonecrosis of the femoral head (ONFH). Human umbilical cord mesenchymal stem cells (hUC-MSCs) have been used in several diseases models, which were reported to be involved in the angiogenesis. However, whether hUC-MSCs suppress the GC-induced ONFH via promoting angiogenesis is still unclear. hUC-MSCs were isolated from the Wharton's jelly using the explant culture method. A GC-induced ONFH model was established in vitro and in vivo. The angiogenesis, proliferation and migration ability of HMECs were determined using the tube-forming, CCK-8, transwell and scratching assays in vitro. The protective role of hUC-MSCs in GC-induced ONFH was evaluated using micro-CT scanning and histological, immunohistochemical (IHC) and Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) assays in vivo. The results showed that hUC-MSCs treatment improved the tube-forming, proliferation and migration ability of HMECs in vitro. Moreover, hUC-MSCs treatment enhanced the integrity of trabecular bone of the femoral head, and the tube-forming ability in vivo. hUC-MSCs prevent the femoral head against necrosis and damage caused by GCs though promoting angiogenesis. [ABSTRACT FROM AUTHOR]

Sandy soil has poor water-holding performance, making it difficult for plants to survive, which worsens the deterioration of the ecological environment. Therefore, borax cross-linked Gleditsia microphylla galactomannan hydrogel (GMGH) was prepared, and its practicability as a water-retaining agent was analyzed. GMGH exhibited fast self-healing performance (150 s, ≈100%) and a high swelling index (88.70 g/g in pH 9). The feasibility of improving the water absorption and retention properties of sandy soil was explored by mixing different proportions (0.1, 0.3, 0.5 wt % sandy soil) of GMGH and sandy soil. The results showed that sandy soil had a more porous structure after adding 0.5 wt % GMGH, and its water absorption index increased from 15.68 to 38.12%. In an artificial climate box, the water-holding time of the sandy soil was extended from 3 to 23.5 days, and the cycles of water absorption and retention were more than 10 times. Therefore, GMGH has broad application prospects as a potential water-retaining agent for desertification control. [ABSTRACT FROM AUTHOR]

To improve the mechanical strength of borax-crosslinked fenugreek galactomannan hydrogels and broaden the application field of galactomannan-based hydrogels, fenugreek galactomannan (FG) was esterified via octenyl succinic anhydride (OSA), and the parameters affecting the esterification reaction were systematically studied. The optimum process for OSA-modified FG (OFG) was as follows: FG concentration 1.5 wt%, n (OSA): n (FG) = 2, n (4-dimethylamino-pyridine, DMAP): n (FG) = 4, and reaction time 12 h. Under this condition, the degree of substitution (DS) was 0.31, and the product yield was 115.05 %. Characterization of FT-IR, H1 NMR, and HPLC confirmed that the OSA group was successfully introduced into the FG skeleton. The mechanical strength of borax crosslinked OFG hydrogel (OFGH) is 18 times higher than that of FG hydrogel. OFGH shows excellent self-healing, injectable properties and electrical conductivity. This will further expand the application of borax crosslinked galactomannan-based hydrogels in the fields of sensors, drug delivery, and wound dressing. • FG modification was carried out via an electrophilic addition reaction with OSA. • The reaction system of OSA-modified FG was carried out at room temperature. • An OFG with a DS of 0.31 was obtained via orthogonal experiments. • The mechanical properties of OFG hydrogels increased by >18 times. • Hydrogels show excellent self-healing, injectable, and conductive properties. [ABSTRACT FROM AUTHOR]

Biodegradable liquid mulch is considered a promising alternative to plastic mulch for sustainable agriculture. This work proposed a xyloglucan-based liquid mulch with multi-function using a combination of chemical modification and blending methods. The esterification product of tamarind xyloglucan (TXG) from forestry wastes was synthesized with benzoic anhydride (BA). The effect of esterification modification was investigated, and BA-TXG was utilized as a film-forming and sand-fixation agent. The rheological properties, thermal stability, and hydrophobicity were improved following esterification. Additionally, waterborne polyurethane and urea were incorporated into the mulch to enhance its mechanical strength (23.28 MPa, 80.71 %), and homogeneity, as well as improve its nutritive properties. The xyloglucan-based liquid mulch has excellent UV protection, a high haze value (approximately 90 %), and retains water at a rate of 80.45 %. SEM and immersion experiment showed the effect of xyloglucan-based liquid mulch on sustainable sand-fixation. Moreover, the liquid mulch treatment demonstrated an impressive germination rate of 83.8 % and degradation rate of 51.59 % (60 days). The modified polysaccharide film increases stability and slows down the degradation rate. Tamarind xyloglucan-based liquid mulch exhibits powerful and diverse optical properties as well as sand fixation functions, indicating their great potential in sustainable agriculture as an alternative to plastic mulch. [Display omitted] [ABSTRACT FROM AUTHOR]

Polysaccharides-based hydrogel has many advantages such as biocompatibility, self-repair property, and biodegradability. It has been widely applied in various fields and has attracted great attention of researchers. The natural polysaccharides involved in this review include fenugreek gum, guar gum, locust bean gum, gellan gum, sodium alginate, agarose, and konjac glucomannan etc. Borax is a highly effective crosslinking agent for cis-ortho-hydroxyl polysaccharides. This paper focused on the synthesis mechanism, functional additives, characteristics, and applications of borax crosslinked cis-ortho-hydroxyl polysaccharides hydrogels (BHs). Moreover, the factors affecting BHs performance such as temperature, pH, and media were analyzed. Its mechanical and self-repair properties are enhanced by the dynamic and reversible borate/di-diol, which play a significant role in sensors, biomedicine, and tissue engineering. This review summarizes the research progress of BHs for the first time. Additionally, hoping to contribute to the development of this field, the review analyzes the correlation of performance through the SPSS 26 software. [ABSTRACT FROM AUTHOR]

Novel rare-earth free green-emitting phosphor Na 2 ZnSiO 4 :Mn2+ was prepared by conventional high temperature solid state reaction method in the carbon reducing atmosphere at 900 °C. The crystal structure was confirmed by X-ray diffraction (XRD) and the structure information was refined by the Rietveld method. The luminescence properties of Na 2 ZnSiO 4 :Mn2+ phosphors as a function of Mn2+ concentrations were investigated. The excitation band peaking at ∼359, 383, 427, 449, and 467 nm are attributed to ground level 6A 1 (6S) to excited levels 4E(4D), 4T 2 (4D), [4A(4G), 4E(4G)], 4T 2 (4G), and 4T 1 (4G) transitions of Mn2+ ion, respectively, which indicates that Na 2 ZnSiO 4 :Mn2+ phosphor may be excited by (near) ultraviolet and blue region light-emitting diode chip. The narrow emission band peaks at ∼515 nm generated by 4T 1 (4G)→6A 1 (6S) transition of the Mn2+ can exhibit strong green emission. The luminescence mechanism was explained by the Tanabe-Sugano diagram. The optimum Mn2+ doping concentration was 0.5 mol%. The critical distance between Mn2+ was calculated to be 33.7 Å. The concentration quenching mechanism can be interpreted by the dipole-dipole interaction of Mn2+ ions. With the Mn2+ doping concentration increasing in the range of 0.2–0.8 mol%, the lifetime of this phosphor decreased from 7.51 to 7.39 ms. These phosphors also possessed good thermal stability at high temperature, and the emission intensity at 125 °C was about 74.9% of that at 25 °C. The present work suggests that Na 2 ZnSiO 4 :Mn2+ phosphor is a kind of potential green-emitting phosphor to provide a bright green component in the red/green/blue tri-color system w-LEDs. [ABSTRACT FROM AUTHOR]

Abstract Novel red-emitting Eu3+-doped Na 2 ZnSiO 4 phosphors were synthesized by a conventional high temperature solid reaction. The crystal structure was confirmed by X-ray diffraction (XRD) and the morphology was examined by scanning electron microscopy (SEM). The luminescence properties of Na 2-x Zn 1-x SiO 4 :xEu3+ (NZS:xEu) phosphors were investigated by photoluminescence excitation (PLE), emission (PL) spectra and decay curves. The phosphors exhibit abnormal intense red emission which located at 702 nm due to the 5D 0 →7F 4 transition of Eu3+ under the excitation of 393 nm and it makes the CIE chromaticity coordinates of the phosphors to fall in a red region. This phenomenon may be explained by the highly polarizable chemical circumstance. The optimum Eu3+ doping concentration of NZS:xEu is determined to be x = 0.08. The critical distance between Eu3+ was calculated to be 13.36 Å. The concentration quenching mechanism can be interpreted by the quadrupole–quadrupole interaction of Eu3+ ions. The decay curves show double exponential behavior for all concentrations of Eu3+ ions and the lifetimes varied from 0.67 to 1.3 ms when the Eu3+ doping concentration increased in the range of 4–12 mol%. The quantum yield (QY) of Na 2 ZnSiO 4 :0.08Eu3+ phosphor is calculated to be as high as 88.76%. The present work suggests that Na 2 ZnSiO 4 :Eu3+ phosphor is a promising candidate as a red component for NUV LEDs application. Highlights • The Na 2 ZnSiO 4 :Eu3+ red phosphors were successfully synthesized by a solid-state reaction. • The crystal structure and luminescence properties of the phosphor were investigated in detail. • The phosphors exhibit abnormal intense red emission due to the 5D 0.→7F 4 transition of Eu3+. • The quantum yield (QY) of Na 2 ZnSiO 4 :0.08Eu3+ phosphor reached as great as 88.76%. [ABSTRACT FROM AUTHOR]

CCMHPG was prepared innovatively in one step using [AMIM]Ac as the reaction medium, and CTA, sodium chloroacetate and propylene oxide as modifiers. The effects of the three modifiers' dosage, alkali dosage, reaction temperature and reaction time on the degree of substitution and viscosity of the product were studied to determine the optimum preparation conditions.The results showed that the water solubility of the reaction product was good, the viscosity of 1 % aqueous solution was 1 072 mPa ⋅ s, the cationic substitution degree was 0.24, the carboxymethyl substitution degree was 0.41 and the hydroxypropyl substitution degree was 0.36. ¹H NMR showed that quaternary ammonium groups, carboxymethyl groups and hydroxypropyl groups were successfully grafted onto guar--gel molecules. SEM showed that wrinkles and scaly cracks were observed on the surface of the particles. The CCMHPG/PAC binary system was used for deinking pulp, the retention rate was 94.3% and the beating degree was 43°SR when adding 0.8% PAC and 0.04% CCMHPG. [ABSTRACT FROM AUTHOR]

Highlights • A series of novel rare-earth free green emitting Na 2 Mg 1-x Ca x SiO4:0.08Mn2+ phosphors were successfully synthesized by a traditional solid-state reaction method. • The luminescence intensity of the phosphor is greatly increased after component modulation.The possible explanation of the mechanism has been given. • The correlation between the structural and the luminescent properties could be exploited to further development of new type luminescent materials. Abstract On the basis of the crystalline structural information that the matrix material has excellent physical-chemical stabilization, green-emitting Na 2 (Mg 1-x Ca x)SiO 4 :Mn2+ (NMCS:Mn2+) phosphors were synthesized by a traditional solid-state method and systematically optimized, and their photoluminescence properties were studied. The luminescence properties of NMCS:Mn2+ phosphors as a function of Ca2+ concentrations were investigated. The structure of the as-prepared phosphors was identified by the X-ray diffraction (XRD) and the luminescent properties were characterized by the luminescence spectra, decay curve and CIE chromaticity coordinates. The emission peaks at 520 nm generated by 4T 1 (4G)→6A 1 (6S) transition of the Mn2+ doped NMCS phosphors can provide a green component in the tri-color system. The emission intensity would be enhanced greatly by Ca2+-substitution and it can be observed that these emission peaks would shift to shorter wavelengths (blue-shift) with the increasing of Ca2+ content. The large enhancement of emission intensity and the shift of emission peaks due to Ca2+ substitution may provide a reference in the research of new type and more efficient phosphors for NUV-LEDs. [ABSTRACT FROM AUTHOR]

• Swelling index of FGB (115) was higher than that of guar gum hydrogel. • Swelling index of sand soil increased from 16.28% to 35.53% with 0.5 wt.% FGB hydrogel. • Water retention time of sandy soil increased from 2 to 11.5 days with 0.5 wt.% FGB hydrogel. • The cycles (water absorption and water loss) of soil-FGB can continue more than ten times at a temperature of 50 °C. • The FGB has swift self-healing capability and injectable performance. In order to explore a novel type of agricultural water-retaining agent, borax crosslinked fenugreek galactomannan-borax hydrogel (FGB) was synthesized. The hydrogel was characterized by thermogravimetric analysis, FT-IR, XRD, and SEM. The largest swelling index of FGB (115) was higher than that of guar gum hydrogel (70) at pH 9. The water absorption capacity of sandy soil was studied by mixing the hydrogel with soil, then FGB was evaluated as a latent water retention agent. Results showed that the swelling index of sandy soil increased from 16.28% to 35.53% with 0.5 wt.% hydrogel added. The water retention time increased from 2 to 11.5 days at 20 °C and 60 % humidity. Furthermore, more than ten cycles of water absorption and water loss of soil-FGB were carried out at 50 °C at a relatively stable water retention capacity. This low-cost, environmentally friendly hydrogel has great application potential in agriculture for soil water conservation. [ABSTRACT FROM AUTHOR]

• Hydrogels can rapidly polymerize within 1 min without introducing additional energy. • Binary solvents improved the environmental tolerance of TA and Cu2+ based hydrogels. • The catalytic effects of Cu2+ and TA in binary solvent environment was verified. • This strategy endows hydrogels excellent adhesion, flexibility and conductivity. • This hydrogel becomes a strong candidate for an electronic skin sensor. Conductive hydrogels have broad application prospects in skin sensors and biomedical monitoring. However, the time-consuming and energy-consuming polymerization process and functional declination in harsh environments hinder its practical application. Herein, highly ionic conductive hydrogels with adhesiveness, flexibility, water-retention and anti-freezing properties are fabricated by a facile and rapid strategy through the combination of tannic acid coated cellulose nanofibers (TA@CNF), metal ion Cu2+, glycerol and polyacrylamide (PAM) chains. Interestingly, the reversible redox catalytic system constructed by TA and Cu2+ in an alkaline environment can significantly shorten the time required (<1 min) for hydrogel polymerization at room temperature. Meanwhile, hydrogen bonds between glycerol and water molecules elevate hydrogel environmental tolerance (-20 to 60 °C), endowing them with excellent flexibility and reproducible adhesion in a long-term usage environment. CNFs, as nano-reinforcements, construct a three-dimensional network structure with PAM for energy dissipation through multiple bonding and endowing the hydrogel with excellent mechanical strength (156.4 kPa) and stretchability (1624.8 %) while providing a tough and stable electron transport network for copper ions, which in turn exhibits excellent electrical conductivity (43.6 mS/m). Obviously, this strategy of preparing multifunctional hydrogels based on catechol metal ion rapid catalytic system will provide a new way for the design and development of advanced skin sensors. [ABSTRACT FROM AUTHOR]

This study attempted to solve the problem of conventional standard display devices encountering difficulties in displaying high dynamic range (HDR) images by proposing a modified tone-mapping operator (TMO) based on the image color appearance model (iCAM06). The proposed model, called iCAM06-m, combined iCAM06 and a multi-scale enhancement algorithm to correct the chroma of images by compensating for saturation and hue drift. Subsequently, a subjective evaluation experiment was conducted to assess iCAM06-m considering other three TMOs by rating the tone mapped images. Finally, the objective and subjective evaluation results were compared and analyzed. The results confirmed the better performance of the proposed iCAM06-m. Furthermore, the chroma compensation effectively alleviated the problem of saturation reduction and hue drift in iCAM06 for HDR image tone-mapping. In addition, the introduction of multi-scale decomposition enhanced the image details and sharpness. Thus, the proposed algorithm can overcome the shortcomings of other algorithms and is a good candidate for a general purpose TMO. [ABSTRACT FROM AUTHOR]

The nuclear norm-based tensor completion method effectively recovers missing multidimensional data in videos by minimizing the truncated nuclear norm. However, the conventional thresholding approach might overly punish larger singular values, which leads to loss of faithful information. In order to overcome this challenge, an improved model of the truncated nuclear norm-based tensor completion is proposed. This improved model is designed to incorporate information related to the prior rank and ensure the preservation of essential singular values to improve the approximation of the matrix rank. First, a video tensor is decomposed into matrices along different modes, and these matrices are divided into similar block matrices by using the K-means＋＋ clustering method, which utilizes the non-local similarity to reduce the influence of noise in the video. Afterwards, a ranking algorithm based on noise matrix analysis is used, which automatically gets the truncated threshold by iterative optimization. Additionally, we propose back-projection method to balance local and global optimization. Finally, to evaluate our proposal, extensive experimental evaluations have been carried out and show that our approach outperforms a lot of recent tensor completion techniques in terms of quality metrics and visual impact. [ABSTRACT FROM AUTHOR]

Abstract: Surface treatment of ruthenium dye (Bu4N)2[Ru(dcbpyH)2(NCS)2]-sensitized TiO2 films using diethyl 4-methylphenylphosphonate as a coadsorbent results in large improvements in DSC performance, 24% larger overall conversion efficiency and 55mV higher open-circuit voltage without current penalty. Introducing another two coadsorbents ethyl 4-methylphenylphosphonate and 4-methoxyphenylphosphonic acid brings in negative effects. Analysis by impedance spectroscopy indicated that this was attributed to different numbers of proton-releasing hydroxyl groups of the coadsorbents and consequently different proton-adsorbing chemical environments on the surface of TiO2 photoanodes. [Copyright &y& Elsevier]

The blood-brain barrier (BBB) comprises the interface between blood, brain and cerebrospinal fluid. Its primary function, which is mainly carried out by tight junctions, is to stabilize the tightly controlled microenvironment of the brain. To study the development and maintenance of the BBB, as well as various roles their intrinsic mechanisms that play in neurological disorders, suitable measurements are required to demonstrate integrity and functional changes at the interfaces between the blood and brain tissue. Markers and plasma proteins with different molecular weight (MW) are used to measure the permeability of BBB. In addition, the expression changes of tight-junction proteins form the basic structure of BBB, and imaging modalities are available to study the disruption of BBB. In the present review, above mentioned methods are depicted in details, together with the pros and cons as well as the differences between these methods, which maybe benefit research studies focused on the detection of BBB breakdown. [ABSTRACT FROM AUTHOR]

Despite a number of studies have emphasized the extensive role of microRNA (miRNA) in the development of multiple cancers, the role of miR-30a-5p in the progression of osteosarcoma (OS) and the underlying mechanism are still limited. We detected the expression level of MiR-30a-5p and forkhead box D1 (FOXD1) in Clinical OS specimens and found that miR-30a-5p was significantly decreased while FOXD1 was markedly increased. Dual luciferase assay confirmed that FOXD1 was directly regulated by miR-30a-5p. In vitro assay showed that inhibitior of FOXD1 suppressed cell proliferation, migration and invasion in MG63 and U2OS cells, while overexpression of FOXD1 promoted OS cell proliferation and migration. In vivo assay further showed the inhibition of tumor growth after knockdown of FOXD1. These results suggested that FOXD1 might play key roles in OS development and progression, and was negatively regulated by miR-30a-5p in OS. [ABSTRACT FROM AUTHOR]