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Abstract To address water leakage in tunnels with high water pressure, a new waterproof drainage system was proposed. The system uses a spray-applied material with double-adhesive properties as a waterproof layer, significantly reducing leakages, and incorporates a unique bottom drainage system to reduce water pressure. In order to check the effectiveness of the new drainage system and to analyze the effects of various structural measures on pressure reduction, a numerical seepage analysis was carried out under the conditions of a water head of 160 m and a surrounding rock permeability of 1 × 10−6 m/s. The results show that the maximum water pressure on the secondary lining is 0.6 MPa, which is about 60% reduction compared to a fully enclosed waterproof system and shows a significant pressure reduction. The spacing of the circumferential drainage pipe and the width of the drainage sheet significantly affect the drainage performance, while the arrangement of the drainage system and the size of the bottom drainage pipe have minimal impact. With full consideration of pressure reduction, cost efficiency and construction feasibility, it is recommended to use the following drainage scheme for iterative calculations during the design stage: “1” shaped arrangement, blind pipe diameter of 10 cm, width of drainage sheets of 0.8 m, and drainage spacing of 6 m. By combining the experimentally determined hydrostatic peel-off strength of 1.4 MPa for spray-applied membrane, the applicable scope of the new drainage system was acquired. The research results can provide valuable insights into the application of spray-applied waterproofing membrane in drainage tunnels with high water pressure.

IntroductionLow bone density and lack of medial support are the two most important factors affecting the stability of locking plate fixation for osteoporotic proximal humeral fractures (PHFs). This study aimed to compare the biomechanical characteristics of PHILOS locking plates combined with calcar screws, bone cement, fibular allografts, and medial locking plate support strategies for treating osteoporotic PHFs with medial column instability.MethodsA three-part osteoporotic PHF (AO 11-B3.2) model with metaphyseal loss was generated using 40 synthetic humeri and fixed via four distinct medial support strategies. All models were mechanically tested to quantify the mechanical characteristics. Subsequently, finite element models were created for each biomechanical test case. The stress distribution and displacement of the four different fixation structures were analyzed using finite element analysis.ResultsThe results demonstrated that the PHILOS locking plate combined with the medial locking plate, exhibited the greatest stability when subjected to axial, shear, and torsional loading. Furthermore, the PHILOS locking plate combined with bone cement showed structural stability similar to that of the PHILOS locking plate combined with fibular allograft but with lower stress levels on the fracture surface.DiscussionIn conclusion, the PLP-MLP fixation structure showed superior biomechanical properties under axial, shear, and torsional loading compared to other medial support methods. Repairing the medial support when treating osteoporotic PHFs with medial column instability can enhance the mechanical stability of the fracture end in both the short and long term.

Beam position measurement system can not only provide the beam position monitoring, but also be used for global orbit correction to reduce beam loss risk and maximize acceptance. The Beam Position Monitors (BPM) are installed along the synchrotron to acquire beam position with the front-end electronics and data acquisition system (DAQ). To realize high precision orbit measurement in the main heavy ion synchrotron and cooling storage ring of heavy-ion research facility in Lanzhou (HIRFL-CSRm), a series of alignment and calibration work has been implemented on the BPM and its DAQ system. This paper analyzed the tests performed in the laboratory as well as with beam based on the developed algorithms and hardware. Several filtering algorithms were designed and implemented on the acquired BPM raw data, then the beam position and resolution were calculated and analyzed. The results show that the position precision was significantly improved from more than 100 μm to about 50 μm by implementing the new designed filtering algorithm. According to the analyzation of the measurement results and upcoming physical requirements, further upgrade scheme for the BPM DAQ system of CSRm based on field programmable gate array (FPGA) technology was proposed and discussed.

ABSTRACT Gut microbiota and their secreted metabolites have an influence on the initiation and progression of colon cancer. Probiotics are extensively perceived as a potential microbiota-modulation strategy to promote the health of the host, while the effectiveness of preventing colon cancer based on microbiota therapy has not been confirmed, and antitumor mechanisms influenced by microbiota and their metabolites with the intervention of probiotics remain to be further investigated. In vitro, Lactobacillus (JY300-8 and JMR-01) significantly inhibited the proliferation of CT26, HT29, and HCT116 cells. Moreover, we studied the prevention and therapy efficiency of Lactobacillus and its underlying antitumor mechanism through the alteration of gut microbiota and their metabolites regulated by Lactobacillus in colon cancer models in mice. We demonstrated that the pre-administration of Lactobacillus (JY300-8 and JMR-01) for 20 days before establishing tumor models resulted in an 86.21% reduction in tumor formation rate compared to tumor control group. Subsequently, continuous oral administration of living Lactobacillus significantly suppresses tumor growth, and tumor volumes decrease by 65.2%. Microbiome and metabolome analyses reveal that Lactobacillus suppresses colonic tumorigenesis and progression through the modulation of gut microbiota homeostasis and metabolites, including the down-regulation of secondary bile acids, sphingosine 1-phosphate (S1P), and pyrimidine metabolism, as well as the production of anticarcinogenic compounds in tumor-bearing mice. Additionally, metabolome analyses of Lactobacillus (JY300-8 and JMR-01) indicate that living Lactobacillus could reduce the relative abundance of alanine and L-serine to suppress tumor progression by regulating the tumor microenvironment, including down-regulation of pyrimidine metabolism and S1P signaling in cancer. These findings provide a potential prevention strategy and therapeutic target for colon cancer through the intervention of dietary Lactobacillus. IMPORTANCE The modulation of gut microbiota and metabolites has a significant influence on the progression of colon cancer. Our research indicated that the intervention of probiotics is a potentially feasible strategy for preventing colon cancer. We have also revealed the underlying antitumor mechanism through the alteration of gut microbiota and their metabolites, which could lead to broader biomedical impacts on the prevention and therapy of colon cancer with microbiota-based therapy regulated by probiotics.

Abstract Background The major challenge of facing the efficient utilization of biomass is the high cost of cellulolytic enzyme, while the Trichoderma longibrachiatum plays an essential role in the production of industrial enzymes and biomass recycling. Results The cellulase hyper‑producing mutants of LC-M4 and LC-M16 derived from the wild type T. longibrachiatum LC strain through heavy ion mutagenesis exhibited the high-efficiency secretion ability of cellulase and hemicellulose. The FPase activities of LC-M4 (4.51 IU/mL) and LC-M16 (4.16 IU/mL) mutants increased by 46.91% and 35.5% when compared to the LC strain, respectively. Moreover, these two cellulase hyper-producing mutants showed faster growth rate on the cellulosic substrates (Avicel and CMC-Na) plate than that of LC strain. Therefore, an integrative transcriptome and proteome profiling analysis of T. longibrachiatum LC and its cellulase hyper‑producing mutant LC-M4 and LC-M16 were employed to reveal the key genes involved in cellulolytic enzymes regulation. It was showed that the transcriptome and proteome profiles changed dramatically between the wild strain and mutant strains. Notably, the overlapped genes obtained from integrative analysis identified that the protein processing in ER involved in protein secretory pathway, starch and sucrose metabolism pathway and N-glycan biosynthesis pathway were significantly changed both in cellulase hyper-producing mutants and thereby improving the enzyme secretion efficiency, which maybe the main reason of cellulase hyper-production in LC-M4 and LC-M16 mutants. In addition, the three DEGs/DEPs (PDI, Sec61, VIP36) related with protein secretion in ER and two DEGs/DEPs (OST, MOGS) related with N-glycan biosynthesis were identified as key candidate genes participating in enzyme protein biosynthesis and secretion. Conclusions In this study, a hypothetical secretory model of cellulase protein in filamentous fungi was established on the basis of DEGs/DEPs and key genes identified from the omics analysis, which were of great guidance on the rational genetic engineering and/or breeding of filamentous fungi for improving cellulase production.

The bin packing problem (BPP) is a classic combinatorial optimization problem with several variations. The BPP with conflicts (BPPCs) is not a well-investigated variation. In the BPPC, there are conditions that prevent packing some items together in the same bin. There are very limited efforts utilizing metaheuristic methods to address the BPPC. The current methods only pack the conflict items only and then start a new normal BPP for the non-conflict items; thus, there are two stages to address the BPPC. In this work, an adaption of the jellyfish metaheuristic has been proposed to solve the BPPC in one stage (i.e., packing the conflict and non-conflict items together) by defining the jellyfish operations in the context of the BPPC by proposing two solution representations. These representations frame the BPPC problem on two different levels: item-wise and bin-wise. In the item-wise solution representation, the adapted jellyfish metaheuristic updates the solutions through a set of item swaps without any preference for the bins. In the bin-wise solution representation, the metaheuristic method selects a set of bins, and then it performs the item swaps from these selected bins only. The proposed method was thoroughly benchmarked on a standard dataset and compared against the well-known PSO, Jaya, and heuristics. The obtained results revealed that the proposed methods outperformed the other comparison methods in terms of the number of bins and the average bin utilization. In addition, the proposed method achieved the lowest deviation rate from the lowest bound of the standard dataset relative to the other methods of comparison.

In-situ 2D nanocarbon/calcium aluminate composite (NCAC) was synthesized via a combustion method designed based on aluminothermic reduction using calcium carbonate (CaCO3) as carbon source. The results demonstrate that compared with the pristine product, when the molar substitution rate of CaCO3 for CaO2 in the reactants was 25%, the contents of CaAl2O4 (CA), CaAl4O7 (CA2) and Ca12Al14O33 (C12A7) in the combusted product did not change substantially and were close to those of Secar71. When the molar substitution rate was increased to 50%, the contents of CA and CA2 decreased, and that of C12A7 increased substantially. Interestingly, the nanocarbons generated in-situ in the combusted composite were embedded in calcium aluminate and had a nanoflake morphology (2D) with a thickness of approximately 50 nm, few defects and high graphitization degree. The results of the suspension experiment demonstrate that the floating ratio of NCAC in the suspension after ultrasonic vibration for 10 min was approximately 5.5 wt.%, which is much lower than that (78.8 wt.%) of a carbon black/Secar71 composite powder; thus, the in-situ 2D nanocarbon/aluminate composite had strengthened interfacial bonds and satisfactory separation resistance. These would be favorable for the uniform dispersion of nanocarbons within the matrix, improving the performance of cement-based composites.

The in-situ high-content carbon-containing calcium aluminate cement (HCCAC) with the carbon content of 20.1 wt.% was prepared by the soft chemistry method with citric acid, calcium carbonate, and alumina as raw materials. The cement product was characterized by X-ray diffractometry, scanning electron microscopy, and Raman spectroscopy. In HCCAC, plate-like and fibrous carbon formed by the pyrolysis of organic acids were uniformly embedded between the calcium aluminate grains. Moreover, the carbon floating ratio of HCCAC in water was lower than that of the mechanical mixing powder of calcium aluminate cement (CAC) and carbon black, which indicated that the water dispersion of carbon was improved. Besides, the slag corrosion resistance properties of Al2O3-SiC-C castables bonded with HCCAC and CAC respectively were compared, and the results showed that the corrosion resistance depth of the HCCAC bonded castables was 45% lower than that of the CAC bonded castables. Therefore, HCCCA can be used as a novel binder of carbon-containing refractory castables.

Abstract Heterostructures are an important class of materials with desirable size, morphology, and functionality because of their promising applications in biosensor and photonic communication device. However, no such technology of synthesizing heterojunctions is as convenient as electric welding. Particularly, synthesizing heterojunctions with large lattice‐mismatch has been subjected to a great challenge. Herein, the hybrid heterojunction structures are obtained by in situ chemical transformation from fluoride to oxyfluoride via a laser irradiation‐welding approach (LIWA). Single NaYbF4:Ho3+@YbOF:Ho3+ heterojunctions with unique morphologies including hollow spheres, lollipops and sponge‐like plates, are successfully prepared by deliberate control over precursor particles and light welding parameters. These unique luminescent heterojunctions can not only integrate distinctive properties of fluoride and oxide, but also exhibit the unprecedented convenience for color tunability. This work provides an ultrafast LIWA for the fabrication of lattice‐mismatched heterojunctions in seconds, and LIWA allows tunable laser parameters to control the microstructures and characteristics of heterojunctions for widespread applications.

A detailed understanding of particle stopping in matter is essential for nuclear fusion and high energy density science. Here, the authors report one order of magnitude enhancement of intense laser-accelerated proton beam stopping in dense ionized matter in comparison with currently used models describing ion stopping in matter.

The study aims to explore the corrosion behaviors of 13Cr steel in the high-temperature steam environment. The corrosion behaviors of 13Cr steel were tested in CO2 auxiliary steam drive environment simulated with the HTHP autoclave. The corrosion morphology and product composition were explored by SEM, EDS, XRD and XPS. The exploration results showed the corrosion rate of 13Cr steel in the high-temperature steam environment was less than 0.04 mm/a. The corrosion behaviors of 13Cr steel were mainly affected by temperature and chloride ion concentration. Temperature inhibited steam condensation and the compactness of Cr-rich layer. With the increase in temperature, more droplets were adsorbed on the surface of 13Cr steel and the compactness of the Cr-rich layer is worse. Chloride ions affects the activity of Fe atoms in the metal matrix. When chloride concentration increased, Fe2+ concentration in the solution and FeCO3 content in the rich-Cr layer were increased and the rich-Cr layer became looser. Keywords: CO2 auxiliary steam drive, Temperature, Cl− concentration, Corrosion, 13Cr steel

The properties of Al2O3-SiC-C castables bonded by in-situ carbon containing calcium aluminate cement (CCAC) were investigated in this study. The results showed that after the Al2O3-SiC-C castables were dried at 110°C, their cold crushing strength (CCS) and cold modulus of rupture (CMOR) increased with the percentage of CCAC. The sample with CCAC content exceeding 2.5% by mass (named C2.5) had higher CCS and CMOR values than those of the model Al2O3-SiC-C castables (named BPS) with ball pitch as the carbon source. After being fired at 1100 and 1450°C, all the castables exhibited increased CCS and CMOR values, while the high apparent porosity of the BPS sample lowered its CCS and CMOR values. Compared with the BPS sample, the carbon materials of the castables bonded by CCAC exhibited improved dispersion in the matrix and excellent oxidation resistance, which enhanced the corrosion resistance of the refractory castables.

Probiotics, as novel functional foods via microbiota-modulation to enhance host health and inhibit tumor carcinogenesis, have been attracted considerable interests. L. casei JY, as a potential probiotic, was irradiated by 12C6+ beams and a new mutant strain JY300-8 was generated through three round selections of transit tolerance in the upper human gastrointestinal tract, adhesion ability to Caco-2 cells and inhibitory pathogenic microorganisms, respectively. Interestingly, JY300-8 presented excellent properties, including the strongest adhesion ability (86.81%) to Caco-2 cells to our knowledge and more excellent antimicrobial properties, which was used for the potential candidate probiotic. Additionally, JY300-8 could significantly inhibit the proliferation of Caco-2, HT29 and HCT116 cells in vitro, respectively. Furthermore, there were better therapeutic effects at an early stage in colon cancer mice, which included the similar survival rates (90%) and stronger inhibitory effect on tumor (83.48%), lower treatment cost and less side effects in comparison to the therapy drug (DFUR) for colon cancer (65.65%), which was attributed to promoting the apoptosis of colon cells and enhancing antitumor response via modulation cancer-induced gut microbiota dysbiosis by oral administration of JY300-8. Therefore, JY300-8 has great potential for bio-prophylactic and bio-therapeutic functional food in colon carcinogenesis. This work provided a promising approach that could improve human health, reduce greatly cancer incidence and mitigate cancer progression via modulation gut microbiota by excellent probiotics intervention.

With the rapid development of the city, all kinds of high-rise buildings, large shopping malls and entertainment places have been built one after another. There are some hidden dangers of fire accidents. Effective prevention and monitoring of fire is the focus of fire prevention and control field. As the information source of fire prevention and control, the preparation of fire detection sensor with high sensitivity and short response time is of great significance for fire prevention and monitoring. At present, the commonly used fire detection sensors mainly include CO sensor, temperature sensor and flame sensor. The sensors detect the characteristic parameters in the fire environment and converts non-electric signals such as gas, temperature, and flame light into electric signals to achieve the purpose of fire warning. With the development of material technology in recent years, especially the development of Carbon Nanotube (CNT) technology, a new fire detection sensor represented by CNT materials has emerged. In this paper, the research progress of CNTs in fire detection sensors is reviewed. The applications of CNTs in CO detection, flame light detection and temperature detection are discussed in detail. Finally, the development trend of fire detection sensors based on CNTs is proposed, and the development direction of fire detection sensors in the Internet of things is prospected.

The research activities on warm dense matter driven by intense heavy ion beams at the new project High Intensity heavy-ion Accelerator Facility (HIAF) are presented. The ion beam parameters and the simulated accessible state of matter at HIAF are introduced, respectively. The progresses of the developed diagnostics for warm dense matter research including high energy electron radiography, multiple-channel pyrometer, in-situ energy loss and charge state of ion detector are briefly introduced.