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With the rapid development of transportation in China, the number of tunnels is also increasing. However, tunnels may be affected by fire accidents during operation, and the surrounding rock will be irreparably damaged by high temperature. To investigate the influence of temperature on the physical and mechanical properties of red sandstone, physical properties were determined and the Brazilian splitting test was conducted on red sandstone after thermal treatment from 25 to 600°C. The results show that with increasing temperature, the apparent colour of the red sandstone gradually deepened. The P-wave velocity and Leeb hardness decreased with increasing temperature, and a typical temperature threshold (300°C) was identified. The tensile strength of red sandstone decreased quickly from 25 to 300°C and then decreased slowly from 300 to 600°C. The acoustic emission (AE) signal shows a high degree of consistency with the stress–time curve. As the temperature increased, the AE became more active, and when red sandstone was near failure, the AE signal increased sharply. The failure mode of sandstone mainly consists of a throughgoing main crack and a secondary crack, and the crack width also grows gradually. Moreover, we observe from polarized light microscopy images that the number of fractures in the sandstone also increases as the temperature rises. The variation of physical and mechanical properties of red sandstone is closely related to microstructure. These findings demonstrate that temperature has an obvious weakening effect on the physical and mechanical properties of sandstone, and provide theoretical guidance and significant engineering information for tunnel fire restoration. Thematic collection: This article is part of the Engineering Geology and Hydrogeology of the Anthropocene collection available at: https://www.lyellcollection.org/topic/collections/engineering-geology-and-hydrogeology-of-the-anthropocene

The performances of construction supervisors are essential for the monitoring, control, and coordination of the construction process of a project in order to adhere to a predefined schedule, cost, quality and other factors. However, it is challenging to evaluate their performance due to limitations such as data deficiency, human error, etc. Thus, this paper proposes an approach to data-driven quantitative performance evaluation of construction supervisors by integrating an analytic hierarchy process (AHP) and activity tracking. The proposed approach contains three parts, namely, index extraction, weighting, data-driven index calculation, and then validation by case study. Firstly, performance indexes were developed based on a literature review as well as surveys and function analysis of the information system for construction supervision (CSI system). Then, the weights of and relationships among of the indexes are determined by AHP. After that, with daily workflow and inspection activities tracked in the CSI system, a method and a software module for automatic calculation of indexes were developed. Lastly, the proposed approach was validated by a real-world case. The result showed that the proposed approach can quantify the performance of a construction supervisor systematically and automatically, which shed lights on how to evaluate the performance of a worker based on the tracking of daily activities. The data-driven process enhanced our strong interpretation of member actions and evaluation indexes, and can boost the performance of every member in an organization.

Heat from gas explosions affects the physical and mechanical properties of rock and reduces the stability of tunnels, such as in coal mines. This paper mainly studies the physical and mechanical properties of sandstone after heating and investigates the influences and mechanisms involved. Acoustic emission (AE) monitoring, X-ray diffraction (XRD), scanning electron microscopy (SEM) and polarized light microscopy are used to show that the uniaxial compressive strength (UCS) and peak strain of sandstone change significantly with temperature. In particular, the UCS decreases rapidly at 500 ~ 600 °C due to a transition from $${\alpha }$$ -quartz to $$\upbeta $$ -quartz. The XRD analysis shows that the physical and mechanical properties of sandstone are affected by its mineral composition, as physical and chemical reactions of quartz, muscovite and kaolinite at high temperatures weaken the sandstone. The AE signals increase with temperature and correspond well with observed loading stages, as they reflect the spatiotemporal evolution in internal micro-cracks. The degree of crack opening is low at low temperatures, then cracks become connected with increasing temperature, further explaining the changes in mechanical properties. Polarized light microscopy shows that grain size and pore characteristics are related to mechanical strength; generally, higher strength is associated with smaller grains with a less even size distribution. In addition, thermal and mechanical damage were quantitatively characterized by deriving thermal, comprehensive and dynamic damage factors. The results provide a theoretical reference for mining engineering in high-temperature environments.

On-surface synthesis is a powerful methodology for the fabrication of low-dimensional functional materials. The precursor molecules usually anchor on different metal surfaces

Gemini surfactant acetylene glycol polyethers and polyhydrosilicone oil were used as raw materials to generate the acetylene glycol surfactants with defoaming, antifoaming properties, and polyether modification through a hydrolyzation reaction. A novel silicone surfactant based on acetylene glycol-modified polyoxysilane, which has the advantages of low surface tension and good water solubility. Its structure characterized by infrared. Finally, the new silicone surfactant prepared was emulsified with a composite emulsifier, and a new concrete defoamer was prepared by a mechanical method. The defoaming performance, foam suppression performance and surface tension were tested. The results showed that the new silicone surfactants contained functional groups of acetylene glycol and siloxane. The composite emulsifiers were Span40 and Tween60, which the HLB value was 10, the amount was 5% and the emulsification time was 30 minutes. The prepared new concrete defoamer has good defoaming and antifoaming properties with a low surface tension.

Intelligent construction (IC) has emerged as a new approach to transforming the architecture, engineering, and construction (AEC) industry through the integration of advanced information technologies such as artificial intelligence (AI) and the Internet of Things (IoT). However, due to its interdisciplinary nature, the relevant documents on IC are diverse and fragmented. To provide a comprehensive understanding of research progress and future opportunities in IC and to offer suggestions for both developing and developed countries, this study employed VOSviewer and Gephi to conduct a comparative review of relevant literature from the 21st century. A keyword search of Web of Science (WOS) identified 2788 relevant documents which were subjected to an overall co-citation and co-authorship analysis. To illustrate the differences between developing and developed countries, China, a representative developing country, was taken as the candidate to be compared with developed countries via a co-occurrence analysis. Differences between China and developed countries in the three sub-directions of IC, research foundation and domain knowledge transformation; information perception, fusion, and decision making; and embodied AI, were qualitatively discussed. Finally, four future research directions were suggested: (1) data fusion and decision-making, (2) improving the accuracy and efficiency of knowledge representation, learning, and utilization, (3) the establishment of large, pre-trained models in the field, and (4) embodied AI for taking actions according to the decisions made. This paper provides an overview of the relevant literature and the IC context for practitioners and scholars in the AEC industry in countries with different levels of development, as well as suggestions for the future development of IC. The findings of this study can serve both academia and industry in promoting IC in the AEC industry.

To evaluate whether pathologic complete response (pCR) to neoadjuvant anti-human epidermal growth factor receptor 2 (HER2) therapy is dependent on the HER2 immunohistochemistry (IHC) score. A total of 181 HER2-positive early breast cancer patients who had received neoadjuvant anti-HER2 therapy were included in this study. Associations were examined between IHC score and tumor pCR status (commonly defined by ypT0+ypN0, ypT0/is+ypN0, or ypT0/is). In trastuzumab-based neoadjuvant-treated patients, ypT0+ypN0 was achieved in 46.0% of patients with HER2 IHC 3+ tumors but only 25.0% of patients with HER2 IHC 2+/fluorescence in situ hybridization (FISH)-positive tumors (P = .016). When pCR was defined as ypT0/is+ypN0 or ypT0/is, 54.7% and 61.3% of patients with HER2 IHC 3+ tumors had a pCR, whereas only 29.5% and 38.6% with HER2 IHC 2+/FISH-positive tumors achieved pCR (P = .004 and P = .008, respectively). The association between dual HER2 blockade and pCR was almost exclusively confined to HER2 IHC 3+ tumors (ypT0+ypN0: 61.9% vs 38.9%, P = .013; ypT0/is+ypN0: 71.4% vs 47.4%, P = .009; and ypT0/is: 81.0% vs 52.6%, P = .002) and was absent in HER2 IHC 2+/FISH-positive tumors. Multivariate logistic regression revealed that HER2 IHC 3+ tumors had a significantly higher probability of achieving ypT0+ypN0 (odds ratio [OR], 0.265; 95% confidence interval [CI], 0.109–0.645; P = .003), ypT0/is+ypN0 (OR, 0.221; 95% CI, 0.094–0.521; P = .001), and ypT0/is (OR, 0.254; 95% CI, 0.111–0.583; P = .001) than HER2 IHC 2+/FISH-positive tumors. A significantly better pCR rate was also found in patients with T1 tumors and patients with dual HER2 blockade. The pCR rate was highly correlated with the HER2 IHC score in neoadjuvant anti-HER2 treatment. The addition of pertuzumab to a neoadjuvant trastuzumab-based regimen improved pCR rates, but there was no significant difference in pCR rates in the IHC 2+/FISH-positive group. This suggests that HER2 IHC scores can predict the effectiveness of treatment.

In this work, a 4.5kV/50A 4H-SiC PiN rectifiers with mesa combined with double-JTE structures is successfully developed for high power applications. Two-dimension numerical device simulator Silvaco-TCAD is applied to optimizing the electrical performance of fabricated rectifiers. Mesa-combined double-JTE structure is utilized to achieve a high blocking voltage with a wider optimum process latitude. A forward current is 50 A at room temperature when SiC PiN device bias 4.1 V, while the maximum blocking voltage achieved is 4.7 kV, reaching up to 86% of parallel-plane junction bulk breakdown.

In the new era of Construction 4.0, the application of a large number of intelligent information technologies (ITs) and advanced managerial approaches have brought about the rapid development of intelligent construction management (ICM). However, it is still unclear how to assess the maturity of ICM. In this study, a maturity assessment system for ICM was formulated through literature reviews, questionnaires, expert discussions and a case study. A maturity scoring table containing five assessment dimensions and twenty assessment indicators was developed, and corresponding maturity levels and a radar chart of dimensions were designed. A case study of the assessments of two construction enterprises was conducted to validate that the proposed assessment system could be used by construction enterprises to quantitatively assess their ICM maturities and obtain both overall and specific assessment results. This study also proposed practical improvement methods to improve ICM maturities for construction enterprises with different maturity levels. Furthermore, the study also discussed the development direction of ICM at present and in the short-term future, which should be paid more attention to by the construction industry.

The deformation and failure features of rock formation in deep coal mines are basic mechanical problems in the complex geology environment and complicated excavation process. Under the effect of cyclic loading and unloading, the bearing capacity weakens and damage degree exacerbates significantly, which seriously threatens the safety and stability of the working face. To study the damage characteristics of sandstone, especially the precursor characteristics of acoustic emission (AE), this paper conduct the AE response experiments on sandstone under cyclic loading and unloading. The results show that with the increasing number of cycles, the loading modulus, unloading modulus, total strain energy, elastic energy, and dissipation energy of sandstone in the cycle stage all increase continuously. In the initial loading stage, the sandstone has fewer cycles and lower stress levels, fewer AE ringing counts and energy, and less rock damage. With the increasing cyclic times and loading stress, the damage degree of sandstone increases rapidly in a very short time. The damage variable represented by ringing count is more sensitive than by energy. Just before rock failure, the ringing count and the energy value increase significantly, and the damage curve rises sharply. In addition, AE waveform signals have obvious aggregation characteristics and four main bands. Just before sandstone failure, the main frequency band becomes wider, the low frequency bands f1 and f2 become connected, and the main signal frequency appears abnormally low and high. The waveform signals before sandstone instability and failure show a phenomenon where the low-frequency amplitude is generally at a high level, the high-frequency signal decreases, the amplitude becomes low, and the multipeak phenomenon weakens. The above characteristics of the AE time domain and waveform analysis can be used as the precursor characteristics of sandstone failure and instability. This study can reveal the process of the sandstone deterioration and AE response under the cyclic loading and unloading condition, and has certain guiding significance for roof and floor control in deep roadway, instability warming monitor of working faces, and guarantees for safety production.

The physical and mechanical properties of surrounding rock of high level radioactive waste repository are affected by the heat released by nuclide decay. In this paper, the effects of temperature on P-wave velocity, porosity and tensile strength are investigated, the microstructure of the specimens with different temperature is observed utilizing a polarizing microscope. Brazilian splitting tests on the heated specimens combined with the acoustic emission technology to monitor the rock deformation and failure. It is observed that the P-wave velocity of granite decreases with the increase of temperature. The porosity of granite changes with temperature and has obvious threshold that is the porosity of granite will increase rapidly when the temperature exceeds 500 °C. Besides, the tensile strength of granite shows a linear decrease with the increasing temperature. The results of acoustic emission tests and thin section observations indicate that temperature leads to an increase in the closure and unstable extension of cracks. The findings of the present research can provide reference for construction safety of the rock mass subjected to high temperature.

Nodal chain (NC) semi-metals have the degeneracy of interlacing rings in their band structure in momentum space. With the projection of degenerate rings towards crystal boundaries, there is a special type of surface dispersion appearing at surface Brillouin zone and termed drumhead surface state (DSS). Previously, experimental investigations on photonic NC and DSS have been done on metallic photonic crystals at microwave frequencies. However, far-field detection of DSS and its coupling to radiative modes in free space have not been studied. In the work, we analyze the photonic DSS in a metallic lattice by angle-resolved far-field reflection measurement and numerical simulation at terahertz (THz) frequencies, and reveal its flatness and boundness in band structure, even in the radiation continuum. Particularly, the DSS band can be tuned being from negatively dispersive via flat to positively dispersive by a single surface parameter, and the DSS at Γ point in surface Brillouin zone is in fact a symmetry-protected bound state in the continuum. Our results might have some potential applications towards THz photonics.

Spectral similarity calculation is widely used in protein identification tools and mass spectra clustering algorithms while comparing theoretical or experimental spectra. The performance of the spectral similarity calculation plays an important role in these tools and algorithms especially in the analysis of large-scale datasets. Recently, deep learning methods have been proposed to improve the performance of clustering algorithms and protein identification by training the algorithms with existing data and the use of multiple spectra and identified peptide features. While the efficiency of these algorithms is still under study in comparison with traditional approaches, their application in proteomics data analysis is becoming more common. Here, we propose the use of deep learning to improve spectral similarity comparison. We assessed the performance of deep learning for spectral similarity, with GLEAMS and a newly trained embedder model (DLEAMSE), which uses high-quality spectra from PRIDE Cluster. Also, we developed a new bioinformatics tool (mslookup - https://github.com/bigbio/DLEAMSE/) that allows users to quickly search for spectra in previously identified mass spectra publish in public repositories and spectral libraries. Finally, we released a human database to enable bioinformaticians and biologists to search for identified spectra in their machines. SIGNIFICANCE STATEMENT: Spectral similarity calculation plays an important role in proteomics data analysis. With deep learning's ability to learn the implicit and effective features from large-scale training datasets, deep learning-based MS/MS spectra embedding models has emerged as a solution to improve mass spectral clustering similarity calculation algorithms. We compare multiple similarity scoring and deep learning methods in terms of accuracy (compute the similarity for a pair of the mass spectrum) and computing-time performance. The benchmark results showed no major differences in accuracy between DLEAMSE and normalized dot product for spectrum similarity calculations. The DLEAMSE GPU implementation is faster than NDP in preprocessing on the GPU server and the similarity calculation of DLEAMSE (Euclidean distance on 32-D vectors) takes about 1/3 of dot product calculations. The deep learning model (DLEAMSE) encoding and embedding steps needed to run once for each spectrum and the embedded 32-D points can be persisted in the repository for future comparison, which is faster for future comparisons and large-scale data. Based on these, we proposed a new tool mslookup that enables the researcher to find spectra previously identified in public data. The tool can be also used to generate in-house databases of previously identified spectra to share with other laboratories and consortiums.

Antibiotics contribute a lot to human beings and can kill bacteria effectively. However, more and more studies show that antibiotics can disturb the intestinal microbial community. It has been widely reported that oral antibiotics can reduce the diversity of intestinal microflora, but the effect of intramuscular injection on intestinal microflora is less studied. In this study, we sequenced the intestinal microflora of mice treated with tetracycline by 16SrRNA method, and found that intramuscular injection of tetracycline (TET) can also reduce the intestinal microbial richness of mice. In addition, the results showed that within a certain range (3 mg), with the increase of TET injection concentration, the wind of intestinal microflora in mice decreased significantly. When the injection concentration reached saturation, although the amount of TET injection was increased, the degree of intestinal flora affected was not increased. The results showed that the degree of diversity decrease was in direct proportion to the amount of tetracycline injection in the saturated concentration, but not positively related to the high amount of TET injection after exceeding the saturated concentration.

In this paper, an ICP-OES test method was developed to solve the problems of low accuracy of silica and calcium oxide content and large background interference in the traditional ICP-OES method. In this method, the pretreated solution of cement reference material is directly used as the standard solution for making the standard curve. This method can reduce the background interference and the complicated operation of the traditional single-standard or mixed standard configuration. At the same time, the results can be corrected by using internal standard Cd to reduce the drift interference caused by long working time of the instrument. This method can simultaneously test the contents of calcium oxide, silicon dioxide, iron oxide, aluminum oxide and magnesium oxide in cement. The correlation coefficients of the standard curves of calcium oxide, silicon dioxide, iron trioxide, aluminum trioxide and magnesium oxide were all greater than 0.999. The absolute error of each component was between 0.06% and 0.1%, and the relative standard deviation (RSD) was between 0.42% and 1.71%.

The conversion of skeletal muscle fiber from fast twitch to slow‐twitch is important for sustained and tonic contractile events, maintenance of energy homeostasis, and the alleviation of fatigue. Skeletal muscle remodeling is effectively induced by endurance or aerobic exercise, which also generates several tricarboxylic acid (TCA) cycle intermediates, including succinate. However, whether succinate regulates muscle fiber‐type transitions remains unclear. Here, we found that dietary succinate supplementation increased endurance exercise ability, myosin heavy chain I expression, aerobic enzyme activity, oxygen consumption, and mitochondrial biogenesis in mouse skeletal muscle. By contrast, succinate decreased lactate dehydrogenase activity, lactate production, and myosin heavy chain IIb expression. Further, by using pharmacological or genetic loss‐of‐function models generated by phospholipase Cβ antagonists, SUNCR1 global knockout, or SUNCR1 gastrocnemius‐specific knockdown, we found that the effects of succinate on skeletal muscle fiber‐type remodeling are mediated by SUNCR1 and its downstream calcium/NFAT signaling pathway. In summary, our results demonstrate succinate induces transition of skeletal muscle fiber via SUNCR1 signaling pathway. These findings suggest the potential beneficial use of succinate‐based compounds in both athletic and sedentary populations.

With billions of spectra acquired by MS/MS experiments, spectral library search tool, which is one of the most important tools for spectra identification, needs to be optimized to deal with big data. In this study, we propose an efficient spectral library search method based on faiss, which is a library for efficient similarity search proposed by Facebook-AI research team. Our faiss-based spectral library searching method contains two parts, spectral library's index construction and spectral library searching. In previous one, we embedded spectral library's spectra into vectors and then used faiss index add API to add these vectors to index file; In latter one, we created spectral library searching modular based on faiss index search API and then used this searching modular to search acquired spectra against spectral library's index file. The results show that our proposed method can search out more translation-supported identifications than SpectraST, which verify the effective identification performance of our method, but our method also searches out more unreliable identifications. And our method has a huge advantage in run-time, SpectraST took more than 4 days while our method only took 23 seconds on the test dataset.

With Fe(NO3)3·9H2O and Bi(NO3)3·5H2O as raw materials, different sillenite-type compounds and elemental bismuth were prepared by a facile one-pot solvothermal method using H2O, C2H5OH, (CH2OH)2 and C3H8O3 as solvents, respectively. The structure, morphology, elemental compositions and properties of samples were examined by XRD, SEM, TEM, ICP, XPS, N2 adsorption and desorption, UV-vis DRS and PL. The photocatalytic activities of different samples were evaluated by the photodegradation of RhB under visible-light irradiation (λ > 400 nm), and results show that Bi36Fe2O57 prepared using C2H5OH as the solvent owns the optimum performance. In order to explore the reaction mechanism, an additional experiment was designed to investigate the main active species during the photodegradation process via dissolving different trapping agents in the reaction solution before light irradiation. The results show that superoxide radical anions play a major role in this system since the RhB degradation was significantly suppressed after the addition of benzoquinone.

Multiple types of external stimuli are usually loaded on an energetic material (EM) simultaneously, and thus they have a coupled effect on its decay. Meanwhile, the structures of the EM essentially influence the decay. Thereby, the coupling effects of these stimuli and structures should be considered in assessing the decay and further the safety of EMs. Nevertheless, it is still difficult to clarify the atomistic/molecular details of the coupling effects on the decay and safety mechanisms. In the present work, we perform reactive molecular dynamics simulations in combination with the multiscale shock technique to reveal a shock–preheating–dislocation coupling effect on the decay mechanism of an energetic representative, 1,3,5-trinitro-1,3,5-triazinane (RDX). That is, three factors including shock velocity, preheating temperature, and edge dislocation are accounted as variables for the simulations. Increasing shock velocity and preheating temperature and presenting edge dislocation in crystal both promote ...