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Bearing vibration signal is a kind of time series data, and its time dimension characteristic plays a key role in classification. Using convolutional neural network (CNN) alone to diagnose bearing fault will cause the loss of time dimension information. This results in the decline of diagnosis accuracy. To solve the above problems, a bearing fault diagnosis model combining one-dimensional CNN, bidirectional gated recurrent unit (Bi GRU) and attention mechanism is proposed. Firstly, CNN is used to adaptively extract the local space characteristic of one-dimensional vibration signals. Secondly, the characteristic information is taken as the input of the Bi GRU. Bi GRU is used to perform time dimension fusion on the extracted characteristic information. The attention mechanism is introduced to weigh the characteristic information of a plurality of moments so as to extract a more critical fault characteristic. Finally, the fault characteristic is input into a full connection layer to obtain a classification result, so as to realize intelligent fault diagnosis of the bearing. The experimental result shows the following points. ① On the confusion matrix of the test set, the classification of the bear running state is basically correct. Only some mark types are not completely classified correctly. But the recall rate is more than 95%, and the total fault recognition accuracy rate is 99.3%. ② The t-SNE technology is used to visualize the data after dimensionality reduction processing. The data of each running state of the bearing are well gathered in their own space. Only a small amount of data are mixed into other areas, which shows that the model has strong characteristic extraction capability. ③ Under the condition of constant load, the average accuracy of fault diagnosis of this model is 0.8%, 0.6% and 0.3% higher than that of one-dimensional CNN, Bi GRU and attention CNN models respectively. ④ Under the condition of variable load, this model has better stability than SVM, one-dimensional CNN, Bi GRU, attention CNN and other models. When the load is 2.25 kW, the accuracy rate is more than 85%. The model has the capability to extract one-dimensional CNN local characteristics and the capability to model Bi GRU time-dependent information. The model can further fuse time dimension information among the characteristics after acquiring the bear signal local complex characteristics. And the attention mechanism can further pay attention to the characteristics more relevant to faults. Therefore, the model has better precision.

Background: Cancer is a thorny problem which cannot be conquered by mankind at present and recent researchers have put their focus on tumor microenviroment. Neutrophils, the prominent leukocytes in peripheral blood that accumulate in tumours, serves as frontline cells in response to tumour progression owing to the rapid development of micro biotechnology. Hence, targeted therapy with these neutrophils has made targeting treatment a promising field in cancer therapy. Main body: We broadly summarise some studies on the phenotypes and functions of tumour‐associated neutrophils as well as the unique web‐like products of neutrophils that play a role in cancer progression—neutrophil extracellular traps—and the interactions between neutrophils and the tumour microenvironment. Moreover, several targeted neutrophils therapeutic studies have made some progress and provided potential strategies for the treatment of cancer. Conclusion: This review aims to offer a holistic perspective on therapeutic interventions targeting neutrophils to further inspire more researches on cancer therapies. [ABSTRACT FROM AUTHOR]

In order to promote the further practical application of rock mass explosivity classification in engineering, regression analysis method was used to analyze the correlation of explosivity indicators, and finally determine the four basically unrelated parameters of rock mass tensile strength, density, brittleness index, and integrity coefficient as rating indicators. The sensitivity of each rating index and its weight were determined using orthogonal design experiments. By using the method of fuzzy decision-making, the explosivity of rock mass was rated, and based on the rating index and the basic quality index of rock mass, a formula for predicting the explosive unit consumption of shallow hole blasting in underground mining was derived. The corresponding explosive unit consumption prediction interval for the explosivity level was further derived. This research shows that the fuzzy decision-making method provides a new approach for rock mass explosivity rating, and also proves the correctness of weight allocation and rating index selection. The on-site blasting test has proven the rationality of the predicted range of explosive unit consumption, which can provide certain guiding significance for production blasting and similar engineering practices. [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is a malignant brain tumor. The purpose of this study is to estimate the potential effects and underlying mechanisms of a ubiquitin-specific protease 8 (USP8) small-molecule inhibitor on the phenotypic characteristics of GBM cells. The growth, migration, invasion, and stemness of GBM LN229 and T98G cells were evaluated by conducting cell proliferation, colony formation, wound healing, transwell, Ki-67 staining, spheroid formation, and ionizing radiation assays, and the results collectively showed the suppressive effects of USP8 inhibition on GBM cells. Furthermore, transcriptomic profiling of GBM cells treated with the USP8 inhibitor deubiquitinase (DUB)-IN-1 revealed significantly altered mRNA expression induced by pharmacological USP8 inhibition, from which we confirmed downregulated Aurora kinase A (AURKA) protein levels using immunoblotting assays. Our findings indicated that the proliferation, invasion, and stemness of LN229 and T98G cells were markedly suppressed by USP8 inhibition. Pharmacological USP8 suppression elicits multiple tumor-inhibitory effects, likely through dysregulating various mRNA expression events, including that of the key cell cycle regulator and oncogenic protein AURKA. Therefore, our observations corroborate the GBM-supportive roles of USP8 and suggest pharmacological USP8 inhibition is a viable therapeutic approach to target GBM. The purpose of this study was to investigate the effect and mechanism of action of the USP8 inhibitor DUB-IN-1 on GBM.

This paper proposes a navigation situation assessment method for autonomous surface vehicles (ASVs) in a cooperative hunting environment. By virtue of the repulsion function expressed in the artificial potential field, the navigation situation of hunting ASVs and target ASVs is firstly described. And the hunting situation is also constructed to describe the cooperative hunting. Based on the navigation situation and the hunting situation, a navigation situation assessment method for cooperative hunting of multiple ASVs is designed, where the number of hunting vehicles and the hunting radius can be successfully computed. Simulation results show that this proposed situation assessment method can give an optimised formation pattern and provide an effective reference for cooperative hunting of ASVs.

Radiative cooling technology can emit infrared heat to the outer space through the "sky window" for cooling without consuming energy, which had drawn more and more attention. However, some researches reported that there was a significantly different cooling performance at different atmospheric total water vapor columns (TWC) conditions. In this study, taking a simple single-layer radiative cooling coating containing two kinds of particle mixture (SiO2, TiO2) as example, the spectral effective emissivity of the radiative cooling coating was proposed to evaluate the effect of the atmospheric water vapor on the cooling performance. The spectral effective emissivity of the coating was obtained through multiplying spectral emissivity of the coating by the atmospheric transmittivity, where the spectral emissivity was calculated by combining an algorithm for calculating radiative properties of the multi-particle system with the Monte Carlo ray-tracing method (MCRT). The effects of different atmospheric water vapor on the spectral effective emissivity of the simple single-layer radiative cooling coating containing different particles size, volume fraction and thickness were studied to improve the cooling performance of the coating. The results showed that with increasing TWC from 0 to 7000 atm-cm, the average effective emissivity of the simple single-layer coating decreased from 79.5% to 35.3%, with a decrease of 44.2%. The research results are of great significance to the further application development and the design criterion of radiative cooling materials in different atmospheric water vapor environments.

The existing campus has a large building area, a low level of energy saving, less renewable energy utilization, higher energy consumption, and obvious energy-saving space. Based on the energy audit of Nankai University, this paper proposes a low-carbon campus transformation technology system combining building energy saving, clean heat supply and distributed photovoltaic in view of its problems such as high municipal heating energy consumption, low comfort, high electricity bill, and tight electricity consumption. Because the campus has both winter holidays and there is tidal phenomenon in teaching buildings and dormitory buildings, etc., the heating demand is reduced, so its heating and energy-saving space is large. At the same time, the number of campus building floors is low, the roof is conducive to the installation of photovoltaic, it is estimated that the annual power generation of rooftop photovoltaic installation can reach more than 70% of the campus electricity consumption, combined with energy-saving transformation and smart energy management, it is easy to achieve its low-carbon goals.

As an important part of public buildings, the school’s energy consumption and carbon emissions have received widespread attention. Relying on the existing building energy conservation situation and the energy consumption of Tianjin Yaohua High school, this paper puts forward the existing problems and energy saving space of high school. Based on the goal of low-carbon transformation, the roof and other utilizable conditions were analyzed, the transformation scheme of low-carbon energy system was brought forward, which realizes clean heating, electric energy replacement and domestic hot water supply with PVT coupling with heat pump. According to calculation, it can realize 70% replacement of school electricity, 100% clean heating and 100% consumption of renewable energy. Based on economic analysis, it has strong feasibility, which provides a reference for the subsequent low-carbon transformation of existing high school.

Aiming at the support difficulties of mine galleries under the complex geological conditions of high buried depth, highin situstress and tectonic fractured zones, a novel square-steel-confined-concrete (SSCC) arch centering supporting system is proposed in this paper. To validate the feasibility of this supporting system, a uniaxial compression test on an SSCC short column is performed and the results illustrate that it has better ductility and higher bearing capacity than the U-shaped column. Numerical analysis on the mechanical behaviors of SSCC arch centering is conducted considering three factors of core concrete strength, steel tube thickness and confinable effect coefficient. Two influence indexes of steel tube thickness (μt) and core concrete strength (μc) influencing the ultimate bearing capacity are put forward andμthas more significant influence. Therefore, an SSCC arch centering (side length 150 mm, tube thickness 8 mm and filled C40 concrete) is determined to perform laboratory andin situexperiments. Combined with numerical simulations, the deformation failure behaviours of the SSCC arch centering are eventually obtained. The laboratory experimental results show that the maximum deformation appears near the spandrel of the arch centering and the ultimate bearing capacity is 1286.9kN. An SSCC and a U-shaped arch centerings have been simultaneously used in the supporting system of the gallery in Zhaolou coal mine project, and the monitoring results (after 157 days) show that their average displacement of the SSCC arch centering is 10.33 mm, which is only 18.3% of that obtained in the U36 arch centering. The above research results indicate that this kind of SSCC arch centering supporting system could efficiently control the deformation of the surrounding rock mass in mining galleries. [ABSTRACT FROM AUTHOR]

With the implementation of China’s two-carbon strategy, how to achieve clean heating, especially the construction of a heating system with electricity as the core, has become a research hotpot in the industry. Among them, air source heat pumps, ground source heat pumps and energy storage have become important technical measures. In view of the capacity increase of urban heat exchange stations, combined with regenerative electric boilers and electricity price reform, this paper uses valley electricity for heat storage, and based on economic analysis, the municipal heat network is increased in flexibility and cleanliness, air energy, coupled energy storage clean and low-carbon heating transformation strategy.

The energy use behavior analysis method can dig out the user’s energy use behavior rules from the energy use big data, thereby improving the quality of the grid-side management service in the integrated energy system. Firstly, it summarizes the characteristics of the integrated energy system and constructs the integrated energy system service system; secondly, it summarizes the data-driven electricity consumption behavior analysis research model. Then, it elaborates on the collection and aggregation of electricity consumption information, and refined user classification. Next, the comprehensive application of energy consumption behavior analysis in load forecasting, demand response modeling and other typical scenarios is deeply analyzed. Finally, the challenges that may be encountered in further research are clarified and the follow-up work is prospected.

Flexible and stretchable ion‐conductive elastomers have shown promising applications in wearable flexible sensor devices, biopotential detection, electroluminescent devices, and other areas. However, the currently employed gel‐based ion‐conductive materials encounter issues such as solvent volatilization or leakage. Herein, there is an urgent requirement to develop a solid‐state ionic conductor material that is both safe and reliable, free from issues of liquid leakage. Here, the study reports a solid‐state ion‐conductive elastomer with excellent mechanical properties and high ionic conductivity based on a synergistic strategy of multiple interaction forces. The solid‐state ion−conductive elastomer exhibits high ionic conductivity (1.42 × 10−4 S cm−1 at 25 °C), superior stretchability (≈1550% elongation) and strength (1.48 MPa). Moreover, the solid‐state ion‐conductive elastomer exhibits high resilience and possesses excellent self‐healing ability. The wearable sensor, prepared based on the solid‐state ion‐conductive elastomer with excellent comprehensive performance, not only demonstrates high strain sensitivity but also captures high‐quality epidermal biopotential signals from the human body in biopotential detection. Additionally, the solid‐state ion‐conductive elastomer can serve as an electrode in ionic electroluminescent devices for human wearable applications. It is believed that the solid‐state ion‐conductive elastomer can provide novel opportunities for the advancement of wearable devices and soft ionotronics. [ABSTRACT FROM AUTHOR]

In earlier studies we have proposed that most parton v2 comes from the anisotropic escape of partons, not from the hydrodynamic flow, even for semi-central Au+Au collisions at SNN = 200 GeV. Here we study the flavor dependence of this escape mechanism with a multi-phase transport model. In contrast to naive expectations, we find that the charm v2 is much more sensitive to the hydrodynamic flow than the lighter quark v2, and the fraction of v2 from the escape mechanism decreases strongly with the quark mass for large collision systems. We also find that the light quark collective flow is essential for the charm quark v2. Our finding thus suggests that heavy quark flows are better probes of the quark-gluon-plasma properties than light quark flows.

High momentum transfer processes can be reliably calculated by perturbative quantum chromodynamics (pQCD). Products of those hard processes, high transverse momentum particles, jets, and heavy quarks (hard probes), interact with the quark-gluon plasma (QGP) created in relativistic heavy-ion collisions. Properties of the QGP can be studied by comparing hard probe measurements in heavy-ion collisions to those in p+p collisions or from pQCD calculations. I will present recent results from STAR on hard probe measurements, including a wide range of observables: heavy flavor, dijet transverse momentum imbalance, hadron-jet correlations, γ-jet correlations, and dihadron correlations. I will discuss what we have learned from these measurements.

Objective: To compare the clinical efficacy of robotic and laparoscopic radical surgery in the treatment of middle-low rectal cancers., Methods: From January 2015 to March 2016, intra-operative and postoperative follow-up data of 30 patients with middle-low rectal cancers who underwent robotic radical resection(robot group) and 32 patients with middle-low rectal cancers who underwent laparoscopic radical resection (laparoscopy group)n in our department were retrospectively collected. The distance from cancer to anal margin was less than 10 cm in both two groups and advanced rectal cancers were confirmed by preoperative colonoscopy biopsy. Associated data were compared between two groups., Results: There were 13 males and 17 females in robot group with age of 27 to 85 (mean 59.7) years, disease course of 3 to 12 (mean 6.2) months and clinical stage T2-3N0-1. There were 16 males and 16 females in laparoscopic group with age of 32 to 79 (mean 60.3) years, disease course of 2 to 10(mean 5.9) months and clinical stage T2-3N0-1. The baseline data of two groups were not significantly different (all P>0.05). All the patients in two groups completed operations successfully without conversion to open operation. Compared with laparoscopic group, the blood loss was less [(100.3±43.7) ml vs. (150.3±68.2) ml, t=3.413, P=0.001], the first flatus time [(49.3±12.4) h vs. (58.6±12.5) h, t=2.838, P=0.006] and urinary catheter removal time [(3.0±0.7) d vs. (4.8±0.9) d, t=5.491, P=0.000] were shorter, while the operation time [(217.3±57.8) min vs. (187.9±23.1) min, t=2.772, P=0.009] was longer in robot group. No cancer tissue was observed in resection margin of two groups. Number of harvested lymph node per case (15.2±7.4 vs. 13.9±4.9, t=-0.764, P=0.448), distance from anal margin to tumor distal edge [(7±3) cm vs. (6.5±3) cm, t=-1.952, P=0.056] and postoperative hospital stay [(13.6±1.3) d vs. (13.8±1.8) d, t=0.925, P=0.359] were not significantly different between two groups. No serious complications occurred in two groups during intra-operative and postoperative period. During following up of 3 to 12 (average 8.7) months, 1 case of anastomotic fistula occurred in each group and was cured by conservative treatment without significant difference [3.3%(1/30) vs. 3.1%(1/32), P=1.000]. No sexual dysfunction was found in either groups. Two cases in laparoscopic group presented relapse and metastasis, but no recurrence and metastasis was observed in robot group. There was no death in two groups., Conclusion: Robotic radical surgery in the treatment of middle-low rectal cancers is safe and effective with the advantages of less trauma, less bleeding, rapid recovery of intestinal function and urinary function.