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Through the analysis of the project of gob-side entry retaining in the deep gangue filling 2305S-2# working face of the Xinjulong coal mine, the principle and technology of surrounding rock control of gob-side entry retaining along the deep mining face are discussed. It is found that the use of gangue to fill the goaf of the deep mining face can effectively alleviate the occurrence of violent strata pressure, which is the basis for realizing entry retaining along the goaf. In the Xinjulong coal mine, the gangue wall and concrete-filled steel tube columns are used as roadside support structure. Anchor bolt + W steel belt are used as advance support, monomer column + hinged beam are used as temporary support, and long anchor cable + beam are used as permanent support. Gob-side entry retaining of deep mining working face is successfully realized. The actual measurement results show that the bearing capacity of gangue wall increases slowly, and the deformation is large. The concrete-filled steel tube column has a certain drilling bottom, and the roof cable is easily broken on the side of the remaining roadway. It is necessary to strengthen the lateral constraint of the gangue wall, limit the deformation of the gangue wall, and improve the bearing capacity of the gangue wall. The bottom of the concrete-filled steel tube column needs to be installed with a large backing plate to control the bottom drilling amount, and the roof anchor cable of the roadway must have a certain elongation to realize the coordinated deformation of the anchor cable and the roof.

As a new type of cell death, necroptosis is initiated by tumor necrosis factor receptor 1(TNFR1), and then activated receptor-interacting protein kinase 1(RIP1) and receptor-interacting protein kinase 3 (RIP3), following by the activation of mixed lineage kinase domain-like protein(MLKL) to deliver cell death signal. When necroptosis happens, damage associated molecular patterns (DAMPs) enter into extracellular area through the ruptured cytomembrane, followed by the disordered tissue hemeostasis. In recent years, many researches showed that necroptosis playimportant roles in a few bone related diseases, such as osteoporosis, osteonecrosis, osteosarcoma, etc. Thus, we try to briefly review the researches in this field.

The development of intelligent drug delivery system that can efficiently deliver drug to targeted site and release the cargo in a controlled manner is of great significance for cancer chemotherapy. In the present study, dual redox/pH-sensitive amphiphilic copolymer, cholesterol modified poly (β-amino esters)-grafted disulfide poly (ethylene glycol) methyl ether (PAE(-ss-mPEG)-g-Chol), is successfully synthesized via Michael-type step polymerization using disulfide linkage-containing PEG segment. PEGylated lipid is introduced to fabricate the doxorubicin (DOX)-loaded hybrid polymer-lipid nanoparticles (NPs) with (DOX-HDPLNPs) or without (DOX-HPLNPs) disulfides to receive stable NPs with enhanced loading capacity and improved cellular uptake ability as well as serum stability. The HDPLNPs show not only pH-sensitivity because of poly(β-amino esters) (PAE) residues in main chain but also the redox-responsivity due to the disulfides on the side chains with PEG segments. As expected, the DOX-HDPLNPs exhibited the extended blood circulation time and higher serum stability in normal physiological environment, but once deposited in the tumor microenvironment (e.g. low pH value and high GSH concentration), they underwent a dramatic size transition and charge reversal. These features not only can facilitate the NPs accumulation through the enhanced permeability and retention (EPR) effect and endocytosis by tumor cells but also realize the drug controlled release and more efficient tumor inhibition. The in vitro and in vivo results demonstrate that the DOX-HDPLNPs possess the highest therapeutic efficacy with high cellular uptake and negligible cytotoxicity compared to the controls and free drug. Therefore, the HDPLNPs have good potential as smart delivery platforms for hydrophobic anticancer drug delivery due to high uptake by tumor cells and redox/pH-triggered drug release.

Magnetoelectric composites enjoy large magnetoelectric transfer efficiency at resonance frequency, accompanying a large phase shift. We prepared two magnetoelectric laminate composites to research the origin of large phase shift and magnetoelectric characteristics by electric-field-induced strain and magnetic-field-induced strain. The piezoelectric part plays a dominant role in both the direct and converse magnetoelectric resonances. The electromechanical resonance inspires direct and converse magnetoelectric resonant peaks, and results in the magnetoelectric phase shift of near $\pi $ around the resonance frequency. However, the magnetostrictive part is difficult to inspire the magnetoelectric resonance and phase shift.

Self-assembly of the corresponding europium and terbium salts with designed chiral ligand (S)-5-((2-carboxy-5-oxopyrrolidin-1-yl)methyl)isophthalic acid (H3L) generated two novel 3D coordination polymers {[Eu(L)]·0.5CH3CN}n (1) and {[Tb(L)]·0.5CH3CN}n (2). Single-crystal X-ray diffraction analyses reveal that 1 and 2 are isostructural metal-organic frameworks built from four-stranded helixes. Complexes 1 and 2 are intriguing homochiral porous architectures with 6,6-connected (48∙66∙8)(413∙62) topology, whose homochirality was further confirmed by their solid-state circular dichroism spectra. Thermal analyses disclose that the desolvated frameworks of 1 and 2 can maintain their structural stability below 370 ​°C. Solid-state photoluminescence studies show that 1 and 2 exhibit strong characteristic Eu(III) and Tb(III) emissions with long lifetimes of 1.31 and 1.35 ​ms, respectively. In addition, 1 and 2 also exhibit significant second harmonic generation activities with their intensities of about 0.29 and 0.31 times larger than that of potassium dihydrogenphosphate, respectively. Very importantly, the excellent thermostabilities and strong red and green emissions of 1 and 2 are of great significance for further exploration of their applications in optical devices.

Utilizing chiral terpyridine derivative ligand (S)-2-((4-([2,2′:6′,2″-terpyridin]-4′-yl)benzyl)amino)propanoic acid (HL) and corresponding Ln(NO3)3, five new isostructural homochiral lanthanide metal–organic frameworks [{[Ln2(HL)2(NO3)4(H2O)4]·NO3·Cl·7H2O}n [Ln = Nd (1), Pr (2), Sm (3), Eu (4), Tb (5)] comprised of left- and right-handed helical chains were solvothermally synthesized. Various means such as IR spectroscopy, elemental analysis, powder X-ray diffraction, and thermal analysis were used to characterize the compounds, wherein compounds 1 and 2 were crystallographically characterized. In the structure of representative 1, zwitterionic ligands HL bridge Nd3+ ions through the monodentate coordination of their carboxylates and the tridentate chelation of their terpyridyls, leading to the formation of left- and right-handed helical chains. The adjacent left- and right-handed helical chains are further connected into a 2D helical layer through interchain hydrogen-bonding interactions, and these layers stack up through interlayer π⋯π interactions to form an interesting three-dimensional homochiral cationic architecture with one-dimensional triangular channels wherein guests anions and water are trapped. The compounds were systematically studied with respect to their solid-state optical properties, including CD spectra, and nonlinear optical and luminescent properties, and the results showed that the sensitization effect of HL ligand on the emission of Tb3+ and Eu3+ was better than that of Sm3+.

Tidal flats play a tremendous role for solving the problem of land use because of the crisis of population increments. Many coastal countries have carried out reclamation projects near seas in various degrees for a long time. China currently has about 2.13 million hm2 of tidal flats that are mainly scattered in the delta plains and coastal regions near medium- to large-sized rivers. The tidal flats in China are reserves featuring dynamic growth and a capacity for continuous expansion; the tidal flat area undergoes an annual increase of over 20,000 hm2. In recent years, countries around the world have paid much attention to the marine ecological environment and have taken measures to restrict the scale and range of sea reclamation. Although widespread reclamation of tidal flats in China has taken place, such activities have also brought some negative effect: (1) water overdraft, seawater intrusion, (2) tidal gates and channel silting, (3) environment pollution, unbalanced ecosystem, and (4) loss of wetlands and threats to the survival of species. This paper examines the mechanisms associated with tidal flat dynamic growth, and points out that artificial siltation can greatly increase the growth speed of tidal flats, and the actual measured annual siltation thickness may reach 0.5–2.7 m. At present, this paper proposes a theory relating to the ecological exploitation of this ecosystem as follows: (1) the principle of adjustment to local conditions; (2) the principle of three-dimensional distribution; (3) the principle of ecological balance; (4) the principle of green and environmental protection. In practical terms, this dynamic growth may play a significant role in mitigating conflicts relating to land use demands in coastal areas.

Direct and converse magnetoelectric effects are two opposite processes, which were integrated in a model based on equivalent circuit. Following the piezoelectric and magnetostrictive constitutive equations, we obtained magnetic-mechanical-electric equations, and then built a symmetric equivalent circuit about the magnetoelectric coupling. We equivalently analyzed the direct and converse magnetoelectric effects with this equivalent circuit. The numerical calculations fit the reported results very well, including the magnetoelectric changes with the thickness ratio and frequency, the relative lower converse magnetoelectric resonance frequency, and the phase increase of π around the direct and converse magnetoelectric resonance frequencies. This model helps us understand the magnetoelectric properties deeply, especially for the converse magnetoelectric effect.