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The automation degree of sealing technology in coal mine is insufficient, and the automatic directional drilling rig can improve the automation degree of sealing. A colloidal slip with double friction force for automatic directional drilling machine is designed to solve the problem that the clamping device of automatic directional drilling machine is bad. Two kinds of colloidal structures are proposed to realize the difference of friction between active drill pipe jointing and unjointing, and to ensure the smooth jointing of drill pipe. Using the nonlinear finite element method, Mooney-Rivlin strain energy function was used to describe the mechanical properties of colloid, and the simulation of colloid clamping hole sealer was carried out. The working friction of colloid of different materials was obtained, and the rationality of the two structural colloids was verified. The influence of the compression amount of adhesive strip on the surface of the colloid on the stress of the hole sealer was studied. The effect of the number of adhesive strips on the colloidal surface on the axial friction force was investigated. The results show that natural rubber and polyurethane rubber are reasonable as colloidal materials, the compression of rubber strips is 0.9 mm, and the number of rubber strips is 3.

Objective To explore the influencing factors the combination of acute renal tubular injury （ARTI） in patients with idiopathic membranous nephropathy （IMN） in a multi-ethnic area of Guangxi. Methods From April 2013 to October 2021, 155 patients with IMN diagnosed by renal biopsy and hospitalized at Hechi People's Hospital were recruited. They were assigned into two groups of with ARTI （n = 43） and without （n = 112）. Results Multifactorial Logistic analysis revealed that serum β2 microglobulin （β2-MG） was independently associated with ARTI in IMN patients （OR = 1.06, 95%CI: 1.01 to 1.12, P = 0.014）. AUC value for ROC curve analysis of serum β2 microglobulin for diagnosing ARTI was 0.748. An optimal threshold value of 2.65 mg/L corresponded to a sensitivity of 81.4% and a specificity of 58.04%. According to serum β2 microglobulin level, they were assigned into three groups of low, medium and high. The odds of ARTI spiked 5.01 and 22.89 folds in medium and high groups as compared with low group. And the results of trend test indicated that the odds of ARTI in IMN patients increased with a rising serum β2 microglobulin concentration （P＜0.001）. Stratified interaction test analysis revealed an interaction between serum β2 microglobulin and ARTI in IMN patients among gender, differential degrees of hypoproteinemia and ethnicity （P for interaction ＜0.05）. Conclusion Serum β2 microglobulin is independently associated with ARTI in IMN patients. And an interaction exists between gender, differential levels of hypoproteinemia and ethnicity.

Diabetes mellitus (DM) is a metabolic disease characterized by chronic hyperglycemia due to multiple etiological factors. In diabetics, lipid accumulation may cause lipid peroxidation and cell membrane lipid oxidation, leading to cellular injuries and triggering dysfunctions. Lipid accumulation may also lead to kidney injury in diabetics, such as glomerulosclerosis, tubular injury and loss of podocytes. As a water-soluble low molecular glycoprotein, apolipoprotein C3 (APOC3) is an important factor in the regulation of human lipid metabolism. It is closely involved in the development of diabetes mellitus and related complications through insulin resistance, lipid metabolism disorders, inflammation and oxidative stress. This review summarized the role and mechanism of APOC3 in diabetes and diabetic kidney disease.

[Introduction] The distribution characteristics of mountain fires by using the historical disaster data of mountain fires related to transmission lines in Hubei province has been analyzed. [Method] Based on the mountain fire disaster data of transmission lines in Hubei Province from 2016 to 2021, the methods of mathematical statistics, climate statistics and GIS spatial superposition were used to analyze the spatiotemporal distribution of transmission line mountain fires in Hubei Province as well as the characteristics of the relationship between mountain fires and meteorological, underlying surface, and social humanities factors. [Result] In terms of time, 2019 is the year in which mountain fires occurred most frequently on transmission lines in Hubei in recent years. Autumn and winter are peak seasons for mountain fires, with February and September being the months with a higher risk of occurrence. In terms of space, the eastern part of Hubei Province is the region with frequent mountain fires, while the Yichang and Jingmen regions are the second highest risk areas. The relationship between the mountain fire and the meteorology shows that the precipitation in the month before the occurrence of most mountain fires is 30% to 100% less than the normal level, the temperature is 0.5 ℃ to 3 ℃ higher than the normal level, the humidity is 3.8% to 23% lower than the normal level, and the wind speed is 0.1 to 1.9 m/s higher than the normal level. The relationship between mountain fire and underlying surface shows that mountain fire mainly occurs in cultivated land, accounting for 50.32% of the total. The mountain fires are mainly concentrated in the areas with an altitude below 150 meters and a slope below 6°, and 76.90% of the mountain fires occur on the sunny slope. The relationship between mountain fire and social humanities shows that mountain fire mainly occurs in the towns around the urban circle with a population density of 100~600 people/square kilometer, as well as the buffer zone about 1.6 kilometers away from the road. [Conclusion] Mastering the distribution characteristics of mountain fires related to Hubei transmission lines can help select indicators and determine thresholds for mountain fire risk warning models.

The transportation media of Lu-Ning Oil Pipeline is the mixture of Shengli crude oil and the imported crude oil, which is characterized with high viscosity and high pour point. In February 2022, the pipeline was shut down for nearly 30 hours due to the leakage caused by weld cracking. However, after the restart-up, a trend of foreboding clogging-up appeared in Ningyang?Tengzhou Section with a distance of 147.1 km due to the continuous decrease of flow rate and outlet temperature under the maximum allowable outlet pressure. Finally, this foreboding clogging-up event was successfully handled by injecting hot diesel, and the flow rate returned to normal about 6 days later. Generally, valuable experience has been accumulated from the foreboding clogging-up event and the emergency response for the safety of heating pipelines in large diameter and great station spacing: (1) It is critical to increase the flow rate if the tendency of foreboding clogging-up appears in the pipeline and the outlet pressure approaches to the allowable upper limit. (2) The hot thin oil should be firstly injected into the second half section and the "bottleneck" section of pipeline to clear the key section and the node. (3) The injection ratio of hot thin oil in the initial stage should be slightly higher than the theoretical value and decreases with the stabilization of operation conditions. (4) The heating facilities should be kept in normal operation through hot oil circulation within the station, so as to increase the outlet temperature of crude oil in pipeline. Finally, the following suggestions were proposed: (1) it is very necessary to set in-station circulating section of hot crude oil pipeline. (2) The properties of oil transported by Lu-Ning Pipeline, the transportation law and technologies for flow assurance should be studied in depth. (3) The contingency plan for foreboding clogging-up of pipeline should be clarified and detailed based on operation data mining.

With the advent of intelligent manufacturing and big data, the Made in China 2025 Initiative and Industry 4.0 have been paying increasing attention to automation and intelligent industrial equipment. In the background of the present times, the complexity and intelligence of computer numerical control (CNC) machine tools have been continuously improved, and the types and descriptions of CNC machine tools’ faults have increased, presenting serious challenges to equipment maintenance and diagnosis of CNC machine tools. In order to provide guarantee for accurate fault diagnosis of CNC machine tools, and to prolong the service life of CNC machine tools, it is necessary to improve the performance of named entity recognition system. Accordingly, the named entity recognition in the equipment and faults field of CNC machine tools were studied, taking the historical examinations and repair records of CNC machine tools as the research object. After analyzing the characteristics of fault description in the historical examinations and repair records, a named entity recognition method was proposed based on the combination of bidirectional long short-term memory (BLSTM) and conditional random field with loop (L-CRF). The first step is to input a sentence and segment and label the input sentence. The annotation corpus is combined with the pre-trained generated word vector by using Skip-gram model in Word2vec, and the word vector is converted into a word vector sequence through the word embedding layer. In the second step, the word vector sequence is integrated into the BLSTM layer to learn long term dependency information. The final step is to input the sentence expression into the L-CRF layer to obtain the global optimal sequence. The experimental results show that the method is superior to other named entity recognition methods, which lays a solid foundation for the intelligent maintenance and the real-time diagnostic tasks of CNC machine tools.

To improve the encryption efficiency, the online/offline cryptography was extended to ABE and the primitive of attribute-based online/offline encryption (ABOOE) was proposed. The ABOOE non-trivially splited the encryption process into two phases: the offline phase first executed most of heavy computations prior to knowing the message and the attributes' set; and then the online phase only performed light computations to produce the ciphertext once the attrib-utes' set and the message get available. An ABOOE scheme was first constructed with the CPA security. To enhance its security, the primitive of attribute-based online/offline KEM (ABOOKEM) was also introduced and a concrete ABOOKEM scheme was given, and then a generic transformation was proposed to get security against chosen-ciphertext attack (CCA) for ABOOE from any ABOOKEM with one-wayness. This transformation greatly improved the security for ABOOE without increasing the amount of computation. Compared with the famous ABE schemes, the proposed schemes improved the encryption efficiency and get suitable for power-constrained devices.

The antibacterial hyperbranched polyurethane (HABPU) was obtained by grafting modification of self-made hyperbranched polyurethane (HCPU) with 1, 1-dimethylbiguanide hydrochloride (DBHC). A reverse osmosis membrane with bactericidal function was prepared by electrospinning technology. The surface morphology and properties of the reverse osmosis membrane were characterized by field emission scanning electron microscope (SEM), atomic force microscope (AFM), contact angle meter and solid surface Zeta potential analyzer. The performance of reverse osmosis membrane was characterized by porosity test, reverse osmosis membrane selective permeability test, anti-organic pollution test and antibacterial test. The results show that the surface morphology, roughness and porosity of HABPU modified membrane change less than those of unmodified membrane, and the wettability is enhanced. When pH value of electrolyte solution is 6~7, the surface of HABPU modified membrane is almost non-electrolytic. The permeation flux and rejection rate of the HABPU modified membrane reach (57.5±2.1) L/(m²⋅h) and (95.2±0.5)%, respectively, which are higher than those of the unmodified membrane. After contact with Escherichia coli and staphylococcus aureus for 2 h, the sterilization rate of HABPU modified membrane reach 100%, showing excellent antibacterial properties. [ABSTRACT FROM AUTHOR]

In order to characterize the structure of the beta-lactamase gene and its corresponding mobile genetic elements in Klebsiella pneumoniae, the beta-lactamase genes from 240 clinical Klebsiella pneumoniae isolates were studied. bla CARB-2 , a newly characterized gene, was extensively investigated utilizing next-generation sequencing, PCR, molecular cloning, conjugation, and comparative genomics analysis. We identified 11 beta-lactamase genes among the 240 clinical Klebsiella pneumoniae isolates; the bla CARB-2 gene exists only in one specific isolate (Klebsiella pneumoniae KP1276) (1/240, 0.42%). The bla CARB-2 gene lies on a conjugative plasmid pKP1276-82, a 182,450-bp plasmid, which encodes 222 open reading frames. The plasmid has seven resistance genes, termed bla CARB-2 , bla KLUC , aadA1, aadA2, cmlA1, dfrA1, and sul2. Among these genes, bla CARB-2 was identified for the first time in Klebsiella pneumoniae. Four of these resistance genes and an int gene form a class 1 integron (int-bla CARB-2 -aadA2-cmlA1-aadA1). Further studies show that the bla CARB-2 , aadA2, and cmlA1 genes are resistant to their corresponding antibiotics and the bla CARB-2 exhibits higher resistance activities to penicillin beta-lactams. These results reveal the possibility of horizontal transfer of the resistance genes and dissemination of resistance among bacteria of different genera or species of Enterobacteriaceae.

Objective: To investigate the effects of Shadu Cao Mixture (SDCM, traditional Chinese medicine) on immune functions of immunosuppression mice., Methods: Fifty BALB/C mice were randomly divided into blank control group, model group, SDCM low-dose, middle-dose and high-dose group. Except the blank control group, other groups were intraperitoneal injected with cyclophosphamide (40 mg/kg) to establish immunosuppression mice model. The blank control group and model group received gavage administration with nonnal saline, while the other groups received gavage administration with different doses of SDCM (10, 20, 40 m/kg for 15 days) respectively. The number of leukocytes and serum levels of interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in peripheral blood, spleen index, and the function of NK cells were measured., Results: Compared with the model group , SDCM increased the number of leukocytes and serum concentrations of IL-2, TNF-α and IFN-γ in peripheral blood and improved the spleen index and the function of NK cells significantly (P < 0.05-0.01)., Conclusion: SDCM could remarkably enhance the immune functions of immunosuppression mice induced by cyclophosphamide.