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In this paper, the research progress made in the methods used for assessing the internal stability of landslide dam soils was reviewed. Influence factors such as the gradation of soil and the stress state in the soil in different analysis methods were discussed, as these can provide a reference for the development of more accurate methods to analyze the internal stability of landslide dam soils. It focuses on the evaluation of internal stability based on the characteristic particle size and fine particle content, hydraulic conditions such as the critical hydraulic gradient and critical seepage velocity, and the stress state such as lateral confinement, isotropic compression, and triaxial compression. The characteristic particle size and fine particle content are parameters commonly used to distinguish the types of seepage failure. The critical hydraulic gradient or seepage failure velocity are necessary for a further assessment of the occurrence of seepage failure. The stress state in the soil is a significant influence factor for the internal stability of natural deposited soils. Although various analysis methods are available, the applicability of each method is limited and an analysis method for complex stress states is lacking. Therefore, the further validation and development of existing methods are necessary for landslide dam soils.

The mechanical properties of grout and the effect of the bonding between grout and the repaired material are the two main factors affecting the shear strength of the material. To study the effect of repairs carried out with nano-Al2O3/epoxy resin composite (NAEC) on the shear strength of rock masses, cracks with different widths and treatments by silane coupling agent (SCA) solutions with various surface treatment concentrations (kSCA) were considered. The mass percentage ratio of nano-Al2O3 in the composite (kAl) was optimized based on the obtained uniaxial compressive strength (UCS). The selected NAEC was used to fill cracks of different widths, and the bonding effect was analyzed using a bilateral shear strength test that effectively avoids the bending effect. Solutions with diverse kSCA values were used to treat the rock surfaces with the 3-mm-wide cracks. The results showed that the UCS of the NAEC tended to increase with increasing kAl when the mass ratio (kCE) of the curing agent to epoxy resin was 0.25. When kAl= 0.01, the UCS of the composite peaked at 97.82 MPa. With increasing crack width, the shear strength first increased and then decreased. When the crack width was 3 mm, the shear strength reached a maximum of 29.02 MPa. However, without nano-Al2O3, the shear strength was 23.66 MPa, and the shear strength of ultrafine Portland cement (UPC) material was only 8.37 MPa. With increasing kSCA, the shear strength tended to first increase and then decrease. For a kSCA of 2%, the shear strength reached a maximum of 39.40 MPa, corresponding to an increase of 35.8%. Nevertheless, the composite shear strength as degraded at 5% kSCA. In summary, the NAEC exhibited a sound bonding effect, SCA surface treatments effectively improved the shear strength, and the bonding shear strength was related to the crack width.

Abstract Nano‐immunotherapy has been recognized as a highly promising strategy for cancer treatment in recent decades, which combines nanotechnology and immunotherapy to combat against tumors. Hybrid nanomaterials consisting of at least two constituents with distinct compositions and properties, usually organic and inorganic, have been engineered with integrated functions and enormous potential in boosting cancer immunotherapy. This review provides a summary of hybrid nanomaterials reported for cancer immunotherapy, including nanoscale metal–organic frameworks, metal–phenolic networks, mesoporous organosilica nanoparticles, metallofullerene nanomaterials, polymer–lipid, and biomacromolecule‐based hybrid nanomaterials. The combination of immunotherapy with chemotherapy, chemodynamic therapy, radiotherapy, radiodynamic therapy, photothermal therapy, photodynamic therapy, and sonodynamic therapy based on hybrid nanomaterials is also discussed. Finally, the current challenges and the prospects for designing hybrid nanomaterials and their application in cancer immunotherapy are outlined.

As a desirable bonding and repair material, epoxy resin combined with other materials is widely used in civil engineering, but its application in underground rock engineering is still limited compared with the wide use of cement grout. To explore and optimize the effect of room temperature-cured bisphenol A epoxy resin E44 on the strength recovery of rock samples with cracks of various widths, the uniaxial compressive strength (UCS) of epoxy resin was studied and the mass ratio of the curing agent to epoxy resin (kCE) was adjusted and optimized. On this basis, the UCS of the selected epoxy resin was investigated by adding diverse amounts of ethanol so that the ratio corresponding to the repair material with better mechanical properties could be selected. Artificial cracks of various widths were filled with the optimized materials, and then, a UCS test was conducted on the repaired rock samples to evaluate the effect on strength recovery and compare it with that of ultrafine Portland cement (UPC). The results show that the UCS of epoxy resin stones increases when kCE ≤ 0.25 and decreases when kCE > 0.25, reaching a peak of 92.41 MPa. Furthermore, as the mass ratio of ethanol to curing agent and epoxy resin (kA) increases, the UCS increases to 94.65 MPa for kCE = 0.25 and kA = 0.01. The crack width influences the UCS of the repaired rock mass. With increasing crack width, the effect of epoxy resin on recovery continuously improves, whereas that of UPC shows the opposite trend. Compared with UPC, epoxy resin has an overwhelmingly greater effect on strength recovery. For instance, for a 3 mm-wide crack, the recovered UCS for 28 d epoxy resin is 83.48 MPa, with much larger peak strains, and the strength recovery rate (kr) is 77.55%; however, the kr of UPC is only 15.12%.

Mangrove National Nature Reserves (MNNRs) play an extraordinarily significant role in conserving mangrove forests and their habitats. In China, one-fourth of the total mangrove forests were located in MNNRs. Understanding annual spatial distributions and conversions of these mangrove forests are important for precision conservation and rehabilitation efforts. However, to date, annual land cover maps of China’s MNNRs are still unavailable. Here, we proposed a rapid and robust approach to produce annual maps of each MNNRs for the time period of 2016–2020 based on 10-m resolution Sentinel-2 imagery. The proposed approach was developed using object-based image analysis, Otsu and Random Forest algorithm. Results showed that 1) during 2016–2020, areal extents of mangrove forest in all the MNNRs continuously increased from 5912 ha to 6128 ha; 2) obvious increase were found in Zhanjiang Mangrove National Nature Reserve where mangrove forest increased by 127 ha, accounted for 59% of national total increases; 3) newly grown mangrove forests were mainly converted from tidal flats and aquaculture ponds. Our annual maps of China’s MNNRs could provide a basis for managing mangrove ecosystems and supporting the implementation of Sustainable Development Goals related to coastal development.

Lake Xingkai is a large turbid lake composed of two parts, Small Lake Xingkai and Big Lake Xingkai, on the border between Russia and China, where it represents a vital source of water, fishing, water transport, recreation, and tourism. Chlorophyll-a (Chla) is a prominent phytoplankton pigment and a proxy for phytoplankton biomass, reflecting the trophic status of waters. Regularly monitoring Chla concentrations is vital for issuing timely warnings of this lake’s eutrophication. Owing to its higher spatial and temporal coverages, remote sensing can provide a synoptic complement to traditional measurement methods by targeting the optical Chla absorption signals, especially for the lakes that lack regular in situ sampling cruises, like Lake Xingkai. This study calibrated and validated several commonly used remote sensing Chla retrieval algorithms (including the two-band ratio, three-band method, four-band method, and baseline methods) by applying them to Sentinel-3 Ocean and Land Colour Instrument (OLCI) images in Lake Xingkai. Among these algorithms, the four-band model (FBA), which removes the absorption signal of detritus and colored dissolved organic matter, was the best-performing model with an R2 of 0.64 and a mean absolute percentage difference of 38.26%. With the FBA model applied to OLCI images, the monthly and spatial distributions of Chla in Lake Xingkai were studied from 2016 to 2022. The results showed that over the seven years, the Chla concentrations in Small Lake Xingkai were higher than in Big Lake Xingkai. Unlike other eutrophic lakes in China (e.g., Lake Taihu and Lake Chaohu), Lake Xingkai did not display a stable seasonal Chla variation pattern. We also found uncertainties and limitations of the Chla algorithm models when using a larger satellite zenith angle or applying it to an algal bloom area. Recent increases in anthropogenic nutrient loading, water clarity, and warming temperatures may lead to rising phytoplankton biomass in Lake Xingkai, and the results of this study can be applied for the satellite-based monitoring of its water quality.

Mangrove forest (MF) extents and distributions are fundamental for conservation and restoration efforts. According to previous studies, both the commercial Gaofen-2 (GF-2) imagery (0.8 m spatial resolution and 4 spectral bands) and freely accessed Sentinel-2 (S2) imagery (10 m spatial resolution and 13 spectral bands) have been successfully used to map MFs. However, the efficiency and accuracy of MF mapping based on these two data is not clear, especially for large-scale applications. To address this issue, first, we developed a robust classification approach by integrating object-based image analysis (OBIA) and random forest (RF) algorithm; and then, applied this approach to GF-2 and S2 images to map the extents of MF along the entire coasts of Guangxi, China, respectively; at last, compared the efficiency and accuracy of GF-2 and S2 imagery in MF mapping. Results showed that: first, based on OBIA and RF integrated classification approach both MF maps derived from GF-2 and S2 obtained high mapping accuracies (the overall accuracy was 96% and 94%, respectively); second, areal extent of MFs in Guangxi extracted from GF-2 and S2 images was 8182 and 8040 ha, respectively; third, GF-2 imagery has extraordinary abilities in detecting fragmented MF patches located along landward and seaward edges; and finally, S2 imagery performed better in detecting seaward submerged MFs and separating MF from terrestrial vegetation. Results and conclusions of this study can provide basic considerations for selecting appropriate data source in MF or wetland vegetation mapping tasks.

Aberration of PI3K signaling pathway has been confirmed to be associated with several hematological malignancies including acute myeloid leukemia (AML). FD268, a pyridinesulfonamide derivative characterized by the conjugation of 7-azaindole group, is a newly identified PI3K inhibitor showing high potent enzyme activity at nanomole concentration. In this study, we demonstrated that FD268 dose-dependently inhibits survival of AML cells with the efficacy superior to that of PI-103 (pan-PI3K inhibitor) and CAL-101 (selective PI3Kδ inhibitor) in the tested HL-60, MOLM-16, Mv-4-11, EOL-1 and KG-1 cell lines. Further mechanistic studies focused on HL-60 revealed that FD268 significantly inhibits the PI3K/Akt/mTOR signaling pathway, promotes the activation of pro-apoptotic protein Bad and downregulates the expression of anti-apoptotic protein Mcl-1, thus suppressing the cell proliferation and inducing caspase-3-dependent apoptosis. The bioinformatics analysis of the transcriptome sequencing data also indicated a potential involvement of the PI3K/Akt/mTOR pathway. These studies indicated that FD268 possesses high potent activity toward AML cells via inhibition of PI3K/Akt/mTOR signaling pathway, which sheds some light on the pyridinesulfonamide scaffold for further optimization and investigation.

Introduction Abdominal surgery is associated with common complications, including decreased or poor appetite, abdominal distension, abdominal pain caused by decreased or absent gastrointestinal motility, anal arrest with flatus and defecation, and nausea and vomiting resulting from the use of anaesthetics and opioid analgesics. These complications seriously affect postoperative recovery, prolong hospital stay and aggravate patient burden. This study aims to investigate for the first time the efficacy of transcutaneous electrical acupoint stimulation (TEAS) combined with electroacupuncture (EA) therapy for rapid recovery after laparotomy for gastrointestinal surgery. There have been no clinical studies of this combination therapy.Methods and analysis This will be a prospective, single-centre, three-arm, randomised controlled trial. A total of 480 patients undergoing abdominal surgery will be stratified according to surgery type (ie, gastric or colorectal procedure) and randomised into three groups; namely, the EA, TEAS +EA and control groups. The control group will receive enhanced recovery after surgery (ERAS)-standardised perioperative management, including preoperative education, optimising the anaesthesia scheme, avoiding intraoperative hypothermia, restrictive fluid infusion and reducing surgical trauma. The EA group will receive EA stimulation at LI4, PC6, ST36, ST37 and ST39 based on the ERAS-standardised perioperative management. Moreover, the TEAS +EA group will receive ERAS-standardised perioperative management; EA stimulation at the LI4, PC6, ST36, ST37 and ST39; and TEAS stimulation at ST21 and SP15. The primary outcome will be the GI-2 (composite outcome of time to first defaecation and time to tolerance of a solid diet). Secondary outcomes will include the time of first passage of flatus, time to first defaecation, time to tolerance of a solid diet, time to first ambulation, hospital duration from operation to discharge, pain and nausea vomiting scores on the Visual Analogue Scale, medication use, incidence of postoperative complications and evaluation of treatment modality acceptability. All statistical analyses will be performed based on the intention-to-treat principle.Ethics and dissemination Ethics approval has been granted by the Ethics Committee on Biomedical Research, West China Hospital of Sichuan University (approval number: 2021; number 52). The results are expected to be published in peer-reviewed journals.Trial registration number ChiCTR2100045646.

Antibacterial coating with antibiotics is highly effective in avoiding device-associated infections (DAIs) which is an unsolved healthcare problem that causes significant morbidity and mortality rates. However, bacterial drug resistance caused by uncontrolled release of antibiotics seriously restricts clinical efficacy of antibacterial coating. Hence, a local and controlled-release system which can release antibiotics in response to bacterial infected signals is necessary in antibacterial coating. Herein, a multi-stimulus responsive multilayer antibacterial coating was prepared through layer-by-layer (LbL) self-assembly of montmorillonite (MMT), chlorhexidine acetate (CHA) and Poly(protocatechuic acid-polyethylene glycol 1000-bis(phenylboronic acid carbamoyl) cystamine) (PPPB). The coating can be covered on various substrates such as cellulose acetate membrane, polyacrylonitrile membrane, polyvinyl chloride membrane, and polyurethane membrane, proving it is a versatile coating. Under the stimulation of acids, glucose or dithiothreitol, this coating was able to achieve controlled release of CHA and kill more than 99% of Staphylococcus aureus and Escherichia coli (4 × 108 CFU/mL) within 4 h. In the mouse infection model, CHA releasing of the coating was triggered by infected microenvironment to completely kill bacteria, achieving wounds healing within 14 days.

Two homoligand 3D coordination polymers [Zn3(BDC4)2HPIP , (2 ) and [Zn3(BDC3)H2BDC)].[C6H15NO.sup.-] were prepared by solvation processes in good yields from a layered precursor Zn3[BDC.sub.3][(H2O).sub 2].4DMF (BDC is terephthalate, DMF is N,N-dimethylformamide). A proposal that 2 follows the crystal growth mechanism of Ostwald ripening is presented.

Two zinc phosphonocarboxylate frameworks, Zn1.5(pbc)(2,2′-bpy) (1) (2,2′-bpy = 2,2′-bipyridine) and Zn(pbc)(NH2(CH3)2)0.5·0.5H3O (2), were synthesized in a mixed-solvothermal condition. Their structures have been determined by single-crystal X-ray diffraction analysis, IR spectra and thermogravimetric analysis. Compound 1is a three-dimensional zinc phosphonocarboxylate with auxiliary ligand of 2,2′-bpy. 2was obtained by reheating the filtrate of 1and shows a nanoporous open-framework with zeolitic GIS topology. At room temperature, 2can absorb organic amine and solvents in its channels, causing a breathing effect and shrinkage of the pores, resulting in single-crystal-to-single-crystal transformation to structure 2a, Zn(pbc)(NH2(CH3)2)·0.5DMF·2H2O. The porosity of 2was demonstrated by the methanol and water adsorption experiments, indicating selective guest uptake. [ABSTRACT FROM AUTHOR]

A green way to synthesize allyl phenols has been developed. Quantitative yield of 2-allyl-4-methoxyphenol was obtained viaa fast Claisen rearrangement in a microreactor system without solvent and work-up. [ABSTRACT FROM AUTHOR]

Six zinc phosphonocarboxylate hybrid materials, namely, Zn 2(pbc) 2·2Hdma·DMF·H 2O ( 1), Zn 2(pbc) 2·H 2teta·H 2O ( 2), Zn(pbc)·H 3O ( 3), Zn 4(pbc) 3·HTEA ( 4), Zn 3(pbc) 2(en) 2( 5), and Zn 3(pbc) 2(H 2O) ( 6) (H 3pbc = 4-phosphono-benzoic acid, DMF = N, N-dimethylformamide, dma = dimethylamine, teta = triethylene tetramine, TEA = triethylamine, en = ethylenediamine) have been synthesized using organic amines as structure-directing agents under mixed-solvothermal condition. These new compounds have been characterized by X-ray single-crystal diffraction together with infrared (IR) spectroscopy, thermogravimetric (TG) analysis, and powder X-ray diffraction (XRD). In structures 1and 2, the double crankshaft chains constructed by the corner-sharing of ZnO 4and CPO 3tetrahedra are cross-linked by the organic moieties of the ligands into three-dimensional (3-D) structures with GIS (gismondine) and GIS-related zeolite topologies. In structure 3, the connectivity between ZnO 4and CPO 3results in inorganic (4.6.12) sheets, which are pillared by the benzoic acid group −C 6H 5−COO− into a 3-D open framework structure with zeolitic SOD (sodalite) topology. Structures 4− 6are pillar-layered structures where the Zn−O−P layers show different configuration due to the directing effect from different organic amines and solvents employed during the synthesis. The results show that the amines and organic solvents acting as structure-directing agents along with control of reaction condition are effective in achieving varieties of zinc phosphonocarboxylate structures. [ABSTRACT FROM AUTHOR]

Abstract  Stem blister canker is a serious stem disease in the Populus genus in China. The pathogen was confirmed as Botryosphaeria dothidea (Moug. ex Fr.) Ces. et de Not. based on its morphological, pathological and molecular features. Seven selected plant species Artemisia annua, Gleditsia sinensis, Lonicera japonica, Macleaya cordata, Phyllodendron chinense, Polygonum cuspidatum and Scutellaria baicalensis, belonging to different families from China, were extracted with the solvent 95% (v/v) ethanol to yield ethanol extracts which were used to evaluate their antifungal activity against poplar stem canker pathogen by a mycelial radial growth inhibition test. Of them, the extracts of M. cordata, P. cuspidatum and S. baicalensis showed stronger antifungal activity, the median inhibitory concentration (IC50) was 0.3125, 1.0219 and 0.9675 mg ml−1 separately. The control effect of extracts of M. cordata, P. cuspidatum and S. baicalensis on poplar stem canker disease was between 62% and 85%. The inhibitory effect of the extracts indicated the importance of some plant species as possible natural source of fungicidal material. [ABSTRACT FROM AUTHOR]

The hydrothermal reaction of Zn(OAc)2·2H2O, H3btc, and 4-bpo affords a novel trinodal four-connected frl topology coordination polymer, [Zn4(btc)2(4-bph)(H2O)4]n·2n(H2O) (4-bphH2is in situsynthesized) (1), which exhibits reversible two-step dehydration–rehydration. [ABSTRACT FROM AUTHOR]

In situ vaccine (ISV) is a versatile and personalized local immunotherapeutic strategy. However, the compromised viability and function of dendritic cells (DCs) in a tumor microenvironment (TME) largely limit the therapeutic efficacy. We designed a hybrid nanoparticle-based ISV, which accomplished superior cancer immunotherapy via simultaneously scavenging reactive oxygen species (ROS) and activating the stimulator of interferon genes (STING) pathway in DCs. This ISV was constructed by encapsulating a chemodrug, SN38, into diselenide bond-bridged organosilica nanoparticles, followed by coating with a Mn2+-based metal phenolic network. We show that this ISV can activate the STING pathway through Mn2+ and SN38 comediated signaling and simultaneously scavenge preexisting H2O2 in the TME and Mn2+-catalyzed •OH by leveraging the antioxidant property of diselenide and polyphenol. This ISV effectively activated DCs and protected them from oxidative damage, leading to remarkable downstream T cell activation and systemic antitumor immunity. This work highlights a nanoparticle design that manipulates DCs in the TME for improving the ISV. [ABSTRACT FROM AUTHOR]

How to further increase the upconversion luminescence (UCL) efficiency of core–shell upconversion nanoparticles (UCNPs) is highly desirable for their photoelectric and bio-logical applications. Herein, a novel but facile strategy is proposed to substantially enhance the UCL intensity of NaYF4 based core–shell UCNPs by morphological control. The morphologies of core–shell UCNPs can be optimized from rod-like to spherical like by changing the ratio of oleic acid (OA) to 1-octadecene (ODE) during the shell growth process with other reaction conditions constant. The mechanism of shape control is further investigated based on the competitive absorption between OA molecules and lanthanide ions (Y3+, Yb3+, Er3+ or Tm3+) onto the different crystal axes (a, b and c) to guide their shell growth speed. The absolute quantum yields were up to 2.7% and 1.8% for spherical and rod like core–shell UCNPs under excitation of 980 nm laser (power density of 1.6 W cm−2), respectively. Moreover, the UCL intensity and effective lifetime (τeff) of Er3+ emission at 541 nm of spherical like core–shell UCNPs increased by 11.7 and 1.82 folds than rod like core–shell UCNPs. Therefore, our designed novel strategy can greatly improve the UCL efficiency of core–shell UCNPs and promote their development in diverse applications. [ABSTRACT FROM AUTHOR]