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The development and deployment of mobile communication systems, personnel and vehicle positioning systems in mines require an analysis of wireless transmission characteristics, the selection of preferred working frequency bands, and the optimization of wireless communication base stations and positioning substations. In this study, wireless transmission tests were conducted in a large frequency range from 350 MHz to 6 GHz in mine environments such as curved tunnels, branch tunnels, main transportation tunnels, excavation tunnels, and fully mechanized mining faces. The test results were analyzed, revealing the characteristics of wireless transmission in mines: ① In curved tunnels, the lower the wireless transmission frequency, the smaller the attenuation, with the least attenuation in the 350 MHz to 900 MHz frequency band. ② In branch tunnels, the lower the frequency, the smaller the attenuation, with the least attenuation in the 350 MHz to 900 MHz frequency band. ③ In main transportation tunnels, the least wireless transmission attenuation was found in the 700 MHz to 900 MHz frequency band. ④ In excavation tunnels, the least attenuation was in the 700 MHz to 900 MHz frequency band. ⑤ In fully mechanized mining faces, the least attenuation was observed in the 433 MHz to 1 300 MHz frequency band. ⑥ With the same cross-sectional area of the tunnels, wireless transmission attenuation in curved tunnels was smaller than in branch tunnels, and the attenuation in branch tunnels emitted from branch sources was smaller than that emitted from main tunnels. Curves and branches in tunnels increased wireless transmission attenuation. Furthermore, this paper proposed the preferred working frequency bands and the best arrangement of antennas for wireless communication systems in underground coal mines, specifically in curved and branch tunnels: ① The working frequency bands for underground wireless communication systems should preferably be in the 700 MHz to 900 MHz range. ② To minimize the impact of curves and branches in tunnels on wireless transmission, wireless communication base stations, positioning substations, and their antennas should be set at the turning points of curved tunnels and at the branch points of branch tunnels. The research results have been applied to the People's Republic of China energy industry standards NB/T 11546-2024 General specification of 5G communication system for coal mines, NB/T 11523-2024 5G communication base station for coal mines, and NB/T 11547-2024 5G communication baseband controller for coal mines.

In order to meet the different requirements of coal mine monitoring, positioning, video, audio, remote control, 5G and other services for latency, reliability, bandwidth and other indicators, the coal mine information comprehensive bearer network should have the following functions. ① The network slicing function supports FlexE interface technology or channelized sub interface technology, and divides port bandwidth resources into different network slices. The services between different network slices are isolated and carried by each other without affecting each other. ② The online bandwidth expansion function of network slicing ensures that there is no packet loss during the bandwidth adjustment process. ③ Network slices set the power-off protection function. ④ The network complies with IEEE 802.3 and TCP/IP protocols, supports IPv6 protocol and IPv6 service bearer, and supports both IPv4 and IPv6 services simultaneously. ⑤ The network supports 10GE optical interface, 1GE optical interface, 10/100/1000 Mbit/s adaptive interface. The core and aggregation nodes should support optical interfaces of 50GE or above. ⑥ It is advisable to use a circular or double ring structure. ⑦ The real time monitoring function for business quality, monitors the delay, jitter, and packet loss rate of specified services in real time. ⑧ 1588v2 clock synchronization function supports 5G base station service access. The main technical indicators of the coal mine information comprehensive bearer network should meet the following requirements. ① The optical port transmission distance should be ≥ 20 km. The transmission distance of the electrical port should be ≥ 100 meters. ② The transmission rate of the backbone network should be ≥ 10 Gbit/s. The transmission rate of the access network should be ≥ 1 Gbit/s. ③ The packet loss rate for different frame lengths is ≤ 0.01% (under 70% network traffic load conditions). ④ The single node transmission delay should be ≤ 1 ms (when the Ethernet frame length is 1518 bytes). ⑤ Node forwarding jitter should be ≤100 μs. ⑥ The number of slices supported by a single interface should be ≥ 5. ⑦ The minimum bandwidth of FlexE interface technology should be ≤1 Gbit/s. The minimum bandwidth of channelized sub interface technology should be ≤ 2 Mbit/s. ⑧ The self-healing time of network reconstruction should be ≤ 50 ms. ⑨ After a power outage in the power grid, the continuous working time of the bearer network equipment under standby power supply should be ≥ 4 hours.

High power radio waves emitted by mobile communication systems such as 5G, 5.5G, WiFi6, WiFi7, UWB, ZigBee, as well as personnel and vehicle positioning systems in mines, pose a risk of igniting gas and coal dust. Therefore, it is necessary to set a reasonable threshold for the explosion-proof safe power of radio waves emitted by explosion-proof radio equipment, and limit the power of radio waves emitted by explosion-proof radio equipment. The European standard CLC/TR 50427:2004 Assessment of inadvertent ignition of flammable atmospheres by radio-frequency radiation-Guide specifies a threshold for the safe reception and ignition power of radio waves in explosive gas environments. But it lacks content on the threshold for the safe transmission power of radio waves. Although the national standard GB/T 3836.1-2021 Explosive atmospheres-Part 1:Equipment-General requirements and the international standard IEC 60079-0:2017 Explosive atmospheres-Part 0:Equipment-General requirements have relevant provisions on the safe transmission power threshold for radio wave explosion protection, they mistakenly modify the safe reception ignition power threshold for radio wave explosion protection in the European standard CLC/TR 50427:2004 to the safe transmission power threshold for radio wave explosion protection. It greatly reduces the maximum transmission power allowed by radio equipment in explosive atmospheres. There’s a lack of slender structural objects such as cranes that can serve as receiving antennas in coal mines. The existing radio communication and positioning systems in mines operate at frequencies far greater than 30 MHz. Therefore, the threshold for the safe reception and ignition power of radio waves should be 8 W, instead of the radio wave explosion-proof safe transmission power threshold of 6 W specified in the national standard GB/T 3836.1-2021 and the international standard IEC 60079-0:2017. When the energy of the radio waves emitted by the transmitting antenna is fully absorbed by the equivalent antenna, which is the most unfavorable for wireless explosion-proof transmission and coupling, and the operating frequency of the radio equipment is the equivalent antenna resonance frequency, the reception and ignition power reaches its maximum. It is half of the total power received by the equivalent antenna, that is, half of the transmission power. In practical engineering, both radio transmission efficiency and coupling efficiency are not equal to 1. Therefore, the threshold for safe transmission power of radio waves should be more than twice the threshold for safe reception and ignition power of radio waves. The threshold for the safe reception and ignition power of underground radio waves in coal mines is 8 W. Therefore, the threshold for the safe transmission power of underground radio waves in coal mines should be greater than 16 W.

The current national standard GB/T 3836.1-2021 Explosive atmospheres-Part 1: Equipment-General requirements and the international standard IEC 60079-0:2017 Explosive atmospheres-Part 0: Equipment-General requirements stipulate that the threshold power of a radio transmitter is the product of the effective output power of the radio transmitter and the antenna gain. Under the condition of a certain threshold for the safe transmission power of radio wave explosion-proof, the larger the antenna gain, the smaller the effective output power of the radio transmitter. This will limit the improvement of wireless transmission distance by increasing the antenna gain. Therefore, it is necessary to study the correctness of the threshold power specified in the national standard GB/T 3836.1-2021 and the international standard IEC 60079-0:2017, and propose reasonable explosion-proof requirements and detection methods for radio wave transmission power. It has been proposed that the safe transmission power of radio waves is independent of antenna gain, and the threshold power of radio transmitters specified in the national standard GB/T 3836.1-2021 and the international standard IEC 60079-0:2017 is incorrect. It is proposed that the threshold for the safe transmission power of underground wireless radio waves in coal mines should be greater than 16 W and independent of antenna gain. The national standard GB/T 3836.1-2021 and the international standard IEC 60079-0:2017 stipulate that the threshold power shall not exceed 6 W, which is incorrect. A method for detecting the explosion-proof safety performance of wireless radio waves has been proposed. The method detects the output power of wireless transmitters. This not only ensures the explosion-proof safety of the detected wireless equipment, but also simplifies the detection method. The method improves the wireless radio wave transmission power of the wireless equipment, removes the limitation on antenna gain, and greatly improves the wireless transmission distance of wireless explosion-proof equipment in coal mines.

The automatic perception and alarm method for coal mine rock burst and coal and gas outburst is an effective measure to timely detect accidents and emergency rescue, reduce casualties, avoid or reduce secondary accidents such as gas and coal dust explosions, and curb delayed, missed, and concealed reporting of accidents. It is difficult to perceive coal mine rock burst accidents, and there is currently no automatic detection and alarm method for coal mine rock burst accidents. Coal mine rock burst accidents are mainly discovered manually. At present, there are only automatic alarm methods for coal and gas outbursts based on methane, wind speed, and direction sensors. There are problems such as slow response speed and inability to detect significant increases in methane concentration before methane sensor damage. A method for image perception and alarm of coal mine rock burst and coal and gas outburst has been proposed. Based on the image features of coal mine rock burst and coal and gas outburst temperature, color, depth, burial, etc., the method recognizes coal mine rock burst and coal and gas outburst. Based on the changes in gas concentration in the roadway space and mining face, the method distinguishes between rock burst and coal and gas outburst. If the gas concentration rapidly increases over a large area, it is judged as coal and gas outburst, otherwise it is judged as rock burst. This method has the advantages of intuitiveness, fast response speed, non-contact, wide monitoring range, simplicity and reliability, and can intuitively record the real situation of coal mine rock burst and coal and gas outburst. When the coal mine rock burst and coal and gas outburst accidents are alarmed, the personnel on duty in the control room can immediately confirm the accident through video recording and carry out emergency rescue in a timely manner. A method has been proposed to reduce the impact of coal mine rock burst and coal and gas outbursts on image perception, including multi point arrangement of cameras, setting of cameras at higher positions, timely transmission of video data, and multi-point arrangement of methane sensors.

A study published in the journal Nephrology Dialysis Transplantation examined the effectiveness of obinutuzumab in treating frequently-relapsing/steroid-dependent minimal change disease (MCD) in adults. The study found that obinutuzumab, a type II anti-CD20 monoclonal antibody, was effective in achieving remission in patients with FR/SD MCD. The study included six patients, and the treatment involved a combination of glucocorticosteroids and obinutuzumab. Further research is needed to determine the long-term efficacy and safety of obinutuzumab for MCD. The article also discusses the use of obinutuzumab in the treatment of focal segmental glomerulosclerosis (FSGS) and minimal change disease (MCD) in adult patients. The study included six patients with FSGS or MCD who were treated with obinutuzumab. After treatment, all six patients achieved complete remission, and there were no relapses during the follow-up period. The study suggests that obinutuzumab may be an effective and safe treatment option for adult patients with FSGS or MCD. However, the study has limitations, including a small sample size and short follow-up time, and further research is needed to fully understand the long-term outcomes and mechanisms of obinutuzumab treatment. [Extracted from the article]

Alpha‐linolenic acid and antioxidant substances (such as tocopherols and polyphenols) are abundant in chia seed oil, which may prevent certain chronic diseases. This study compared the physicochemical parameters, chemical composition and antioxidant properties of black and white chia seed oil extracted by solvent extraction, pressing and supercritical CO2 extraction. Chia seed oil contained higher levels of polyunsaturated fatty acids, including linoleic acid (18.68%–20.15%) and α‐linolenic acid (60.47%–63.68%). Black and white chia seeds and processing methods had significant effects on minor components (tocopherols, total phenols, phytosterols and squalene), oxidative stability and free radical scavenging ability. Compared with other methods, the contents of tocopherols (512.72–603.04 mg/kg), total phenols (35.21–57.75 mgGAE/kg) and phytosterols (5536.69–5956.65 mg/kg) were higher in the pressing method. In addition, 17 individual polyphenols were identified and quantified, among which genistein and gallic acid had higher contents, which were significantly affected by varieties and processing methods. In general, the pressing process may be the best processing method to improve minor components and antioxidant capacity. This study can provide a valuable reference for producing functional foods supplemented with α‐linolenic acid. [ABSTRACT FROM AUTHOR]

Introduction: High serum phosphorus level has been reported to be a risk factor for disease progression in patients with chronic kidney disease, whereas, its role in IgA nephropathy (IgAN) still remains uncertain. This study aimed to investigate the association between serum phosphorus and progression of IgAN. Methods: A total of 247 patients diagnosed with IgAN from 2016.11 to 2019.12 at the First Affiliated Hospital of Xi'an Jiaotong University were retrospectively enrolled in this study. The association between serum phosphorus and kidney disease progression events, defined as 30% estimated glomerular filtration rate (eGFR) decline or kidney failure, was evaluated using Cox models. Results: Serum phosphorus was an independent risk factor for poor renal outcome after adjusting for age, gender, urine protein, MAP, eGFR, hemoglobin, Oxford S and T scores (HR, 2.586; 95% CI, 1.238–5.400, p = 0.011). The addition of serum phosphorus to the reference model containing clinical and pathological variables significantly improved the risk prediction of IgAN progression (C statistic, 0.836; 95% CI, 0.783–0.889) as compared with the reference model (C statistic, 0.821; 95% CI, 0.756–0.886). The ability of serum phosphorus level to predict progression was much stronger in IgAN patients without use of immunosuppression (HR 5.173; 95% CI, 1.791–14.944; p = 0.002). Conclusion: Higher serum phosphorus levels were independently associated with kidney disease progression in patients with IgAN, especially in those without immunosuppression. The addition of serum phosphorus to clinical and pathological data at the time of biopsy significantly improved risk prediction of IgAN progression. [ABSTRACT FROM AUTHOR]

Adipose tissue group 2 innate lymphoid cells (ILC2s) help maintain metabolic homeostasis by sustaining type 2 immunity and promoting adipose beiging. Although impairment of the ILC2 compartment contributes to obesity-associated insulin resistance, the underlying mechanisms have not been elucidated. Here, we found that ILC2s in obese mice and humans exhibited impaired liver kinase B1 (LKB1) activation. Genetic ablation of LKB1 disrupted ILC2 mitochondrial metabolism and suppressed ILC2 responses, resulting in exacerbated insulin resistance. Mechanistically, LKB1 deficiency induced aberrant PD-1 expression through activation of NFAT, which in turn enhanced mitophagy by suppressing Bcl-xL expression. Blockade of PD-1 restored the normal functions of ILC2s and reversed obesity-induced insulin resistance in mice. Collectively, these data present the LKB1-PD-1 axis as a promising therapeutic target for the treatment of metabolic disease. [Display omitted] • LKB1 signaling is impaired in adipose tissue ILC2s from both mice and humans • LKB1 deficiency impairs ILC2 function and promotes obesity-associated insulin resistance • LKB1 sustains ILC2 mitochondrial and effector functions by inhibiting PD-1 expression • Targeting the LKB1-PD-1 axis may be a promising approach to metabolic disease therapy Obesity induces ILC2 dysfunction in adipose tissue and insulin resistance by undetermined mechanisms. Here, Sun et al. show that liver kinase B1 (LKB1) signaling protects ILC2s from mitophagy by suppressing PD-1 expression. Moreover, PD-1 blockade restores ILC2 function and reverses obesity-associated insulin resistance. [ABSTRACT FROM AUTHOR]

Introduction: Group 3 innate lymphoid cells (ILC3s) are enriched in the intestinal mucosa and play important roles in host defense against infection and inflammatory diseases. Sirtuin 6 (SIRT6) is a nicotinamide adenine dinucleotide (NAD+)- dependent deacetylase and has been shown to control intestinal epithelial cell differentiation and survival. However, the role of SIRT6 in ILC3s remains unknown., Methods: To investigate the role of SIRT6 in gut ILC3s, we generated SIRT6 conditional knockout mice by crossing Rorccre and Sirt6flox/flox mice. Cell number and cytokine production was examined using flow cytometry. Citrobacter rodentium infection and dextran sodium sulfate-induced colitis models were used to determine the role of SIRT6 in gut defense. RT-qPCR, flow cytometry and immunohistochemistry were used to assess the intestinal inflammatory responses., Results: Here we show that SIRT6 inhibits IL-22 expression in intestinal ILC3s in a cell-intrinsic manner. Deletion of SIRT6 in ILC3s does not affect the cell numbers of total ILC3s and subsets, but results in increased IL-22 production. Furthermore, ablation of SIRT6 in ILC3s protects mice against Citrobacter rodentium infection and dextran sodium sulfate-induced colitis. Our results suggest that SIRT6 may play a role in ILC3 function by regulating gut immune responses against bacterial infection and inflammation., Discussion: Our finding provided insight into the relation of epigenetic regulators with IL-22 production and supplied a new perspective for a potential strategy against inflammatory bowel disease., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Su, Zhao, Zhang, Wang, Sun and Shen.)

Electrochemical CO 2 reduction reaction (CO 2 RR) powered by renewable energy provides a promising route to CO 2 conversion and utilization. However, the widely used neutral/alkaline electrolyte consumes a large amount of CO 2 to produce (bi)carbonate byproducts, leading to significant challenges at the device level, thereby impeding the further deployment of this reaction. Conducting CO 2 RR in acidic electrolytes offers a promising solution to address the "carbonate issue"; however, it presents inherent difficulties due to the competitive hydrogen evolution reaction, necessitating concerted efforts toward advanced catalyst and electrode designs to achieve high selectivity and activity. This review encompasses recent developments of acidic CO 2 RR, from mechanism elucidation to catalyst design and device engineering. This review begins by discussing the mechanistic understanding of the reaction pathway, laying the foundation for catalyst design in acidic CO 2 RR. Subsequently, an in-depth analysis of recent advancements in acidic CO 2 RR catalysts is provided, highlighting heterogeneous catalysts, surface immobilized molecular catalysts, and catalyst surface enhancement. Furthermore, the progress made in device-level applications is summarized, aiming to develop high-performance acidic CO 2 RR systems. Finally, the existing challenges and future directions in the design of acidic CO 2 RR catalysts are outlined, emphasizing the need for improved selectivity, activity, stability, and scalability., (© 2024 The Authors. Advanced Materials published by Wiley‐VCH GmbH.)