Theory,technology and application of grouted bolting in soft rock roadways of deep coal mines

The grouted bolt,combining rock bolting with grouting techniques,provides an effective solution for controlling the surrounding rock in deep soft rock and fractured roadways.It has been extensively applied in numerous deep mining areas characterized by soft rock roadways,where it has demonstrated remarkable control results.This article systematically explores the evolution of grouted bolting,covering its theoretical foundations,design methods,materials,construction processes,monitoring measures,and methods for assessing its effectiveness.The overview encompassed several key elements,delving into anchoring theory and grouting reinforcement theory.The new principle of high pretensioned high-pressure splitting grouted bolting collaborative active control is introduced.A fresh method for dynamic information design is also highlighted.The discussion touches on both conventional grouting rock bolts and cable bolts,as well as innovative grouted rock bolts and cables characterized by their high pretension,strength,and sealing hole pressure.An examination of the merits and demerits of standard inorganic and organic grouting materials versus the new inorganic–organic composite materials,including their specific application conditions,was conducted.Additionally,the article presents various methods and instruments to assess the support effect of grouting rock bolts,cable bolts,and grouting reinforcement.Furthermore,it provides a foundation for understanding the factors influencing decisions on grouted bolting timing,the sequence of grouting,the pressure applied,the volume of grout used,and the strategic arrangement of grouted rock bolts and cable bolts.The application of the high pretensioned high-pressure splitting grouted bolting collaborative control technology in a typical kilometer-deep soft rock mine in China—the soft coal seam and soft rock roadway in the Kouzidong coal mine,Huainan coal mining area,was introduced.Finally,the existing problems in grouted bolting control technology for deep soft rock roadways are analyzed,and the future development trend of grouted bolting control technology is anticipated.

Phase Ib study of anti-EGFR antibody(SCT200)in combination with anti-PD-1 antibody(SCT-I10A)for patients with RAS/BRAF wild-type metastatic colorectal cancer

Objective:This study evaluated the safety and efficacy of an anti-epidermal growth factor receptor(EGFR)antibody(SCT200)and an anti-programmed cell death 1(PD-1)antibody(SCT-I10A)as third-line or subsequent therapies in patients with rat sarcoma viral oncogene(RAS)/v-raf murine sarcoma viral oncogene homolog B(BRAF)wild-type(wt)metastatic colorectal cancer(mCRC).Methods:We conducted a multicenter,open-label,phase Ib clinical trial.Patients with histologically confirmed RAS/BRAF wt m CRC with more than two lines of treatment were enrolled and treated with SCT-I10A and SCT200.The primary endpoints were the objective response rate(ORR)and safety.The secondary endpoints included disease control rate(DCR),progression-free survival(PFS),and overall survival(OS).Results:Twenty-one patients were enrolled in the study through January 28,2023.The ORR was 28.57%and the DCR was 85.71%(18/21).The median PFS and OS were 4.14 and 12.84 months,respectively.The treatment-related adverse events(TRAEs)were tolerable.Moreover,compared with the monotherapy cohort from our previous phase I study evaluating SCT200 for RAS/BRAF wt m CRC in a third-line setting,no significant improvements in PFS and OS were observed in the combination group.Conclusions:SCT200 combined with SCT-I10A demonstrated promising efficacy in previously treated RAS/BRAF wt m CRC patients with an acceptable safety profile.Further head-to-head studies with larger sample sizes are needed to validate whether the efficacy and safety of combined anti-EGFR and anti-PD-1 therapy are superior to anti-EGFR monotherapy in the third-line setting.(Registration No.NCT04229537).

Transient AC Overvoltage Suppression Orientated Reactive Power Control of the Wind Turbine in the LCC-HVDC Sending Grid

High-voltage direct current(HVDC) transmission is a crucial way to solve the reverse distribution of clean energy and loads. The line commutated converter-based HVDC(LCCHVDC) has become a vital structure for HVDC due to its high technological maturity and economic advantages. During the DC fault of LCC-HVDC, such as commutation failure, the reactive power regulation of the AC grid always lags the DC control process, causing overvoltage in the AC sending grid, which brings off-grid risk to the wind power generation based on power electronic devices. Nevertheless, considering that wind turbine generators have fast and flexible reactive power control capability, optimizing the reactive power control of wind turbines to participate in the transient overvoltage suppression of the sending grid not only improves the operational safety at the equipment level but also enhances the voltage stability of the system. This paper firstly analyses the impact of wind turbine's reactive power on AC transient overvoltage. Then, it proposes an improved voltage-reactive power control strategy, which contains a reactive power control delay compensation and a power command optimization based on the voltage time series prediction. The delay compensation is used to reduce the contribution of the untimely reactive power of wind turbines on transient overvoltage, and the power command optimization enables wind turbines to have the ability to regulate transient overvoltage, leading to the variation of AC voltage, thus suppressing the transient overvoltage. Finally, the effectiveness and feasibility of the proposed method are verified in a ±800kV/5000MW LCC-HVDC sending grid model based on MATLAB/Simulink.

Review of the Analysis and Suppression for High-frequency Oscillations of the Grid-connected Wind Power Generation System

High-frequency oscillation(HFO)of gridconnected wind power generation systems(WPGS)is one of the most critical issues in recent years that threaten the safe access of WPGS to the grid.Ensuring the WPGS can damp HFO is becoming more and more vital for the development of wind power.The HFO phenomenon of wind turbines under different scenarios usually has different mechanisms.Hence,engineers need to acquire the working mechanisms of the different HFO damping technologies and select the appropriate one to ensure the effective implementation of oscillation damping in practical engineering.This paper introduces the general assumptions of WPGS when analyzing HFO,systematically summarizes the reasons for the occurrence of HFO in different scenarios,deeply analyses the key points and difficulties of HFO damping under different scenarios,and then compares the technical performances of various types of HFO suppression methods to provide adequate references for engineers in the application of technology.Finally,this paper discusses possible future research difficulties in the problem of HFO,as well as the possible future trends in the demand for HFO damping.

Grouting theories and technologies for the reinforcement of fractured rocks surrounding deep roadways

Grouting is an effective method to improve the integrity and stability of fractured rocks that surround deep roadways.After years of research and practice,various theories and a complete set of grouting technologies for deep roadways with fractured rocks have been developed and are widely applied in Chinese coal mining production.This paper systematically summarizes and analyzes the research results concerning the theory,design,materials,processes,and equipment for the grouting and reinforcement of fractured rocks surrounding deep roadways.Specifically,in terms of grouting methods,pregrouting,groutingwhile-excavation,and postgrouting methods are explored;in terms of grouting theory,backfill grouting,compaction grouting,infiltration grouting,and fracture grouting theories are studied.In addition,this paper also studies grouting borehole arrangement,water-cement ratio,grouting pressure,grouting volume,grout diffusion radius,and other grouting parameters and their determination methods.On this basis,this paper explores the physical and mechanical properties of organic and organic-inorganic composite grouting materials,and assess grouting reinforcement quality testing methods and instruments.Taken as the field cases,the application of pregrouting in front of heading faces,groutingwhile-excavation,and postgrouting in the Kouzidong coal mine are then introduced,and the effects of the grouting reinforcements are evaluated.This paper proposes a development direction for grouting technology based on problems existing in the grouting reinforcement of fractured rocks surrounding deep roadways.

In-situ structural evolution analysis of Zr-doped Na_(3)V_(2)(PO_(4))_(2)F_(3) coated by N-doped carbon layer as high-performance cathode for sodium-ion batteries

With great superiorities in energy density,rate capability and structural stability,Na_(3)V_(2)(PO_(4))_(2) F_(3)(NVPF)has attracted much attentions as cathode of sodium ion battery(SIB),but it also faces challenges on its poor intrinsic electronic conductivity and the controversial de/sodiation mechanism.Herein,a series of Zr-doped NVPF coated by N-doped carbon layer(~5 nm in thickness,homogenously)materials are fabricated by a sol-gel method,and the optimized heteroatom-doping amounts of Zr and N doping improve intrinsic properties on enlarging lattice distance and enhancing electronic conductivity,respectively.Specifically,among all samples of Na_(3) V_(2-x)Zr_(x)(PO_(4))_(2) F_(3)/NC(NVPF-Zr-x/NC,x=0,0.01,0.02,0.05,and 0.1),the optimized electrode of NVPF-Zr-0.02/NC delivers high reversible capacities(119.2 mAh g^(-1) at0.5 C),superior rate capability(98.1 mA h g^(-1) at 20 C)and excellent cycling performance.The structural evolution of NVPF-Zr-0.02/NC electrode,in-situ monitored by X-ray diffractometer,follows a step-wise Na-extraction/intercalation mechanism with reversible multi-phase changes,not just a solid-solutionreaction one.Full cells of NVPF-Zr-0.02/NC//hard carbon demonstrate high capacity(99.8 mA h g^(-1) at 0.5 C),high out-put voltage(3.5 V)and good cycling stability.This work is favorable to accelerate the development of high-performance cathode materials and explore possible redox reaction mechanisms of SIBs.

血浆HOXA7基因甲基化在非小细胞肺癌诊断中的应用

目的:检测非小细胞肺癌(non-small cell lungcancer,NSCLC)血浆中同源盒基因(homeobox,HOX)家族成员HOXA7基因启动子甲基化水平,并评估HOXA7甲基化与肿瘤标志物血清癌胚抗原(carcinoembryonic antigen,CEA)、糖类抗原(carbohydrate antigen199,CA199)和细胞角蛋白19片段抗原21-1(cytokeratin 19 fragment antigen 21-1,Cyfra21-1)水平辅助诊断NSCLC的价值。方法:选取河南省肿瘤医院2012年1月至2016年12月住院的经病理组织学确诊为NSCLC患者80例为试验组,50例健康人为对照组。采用定量甲基化特异性PCR(quantitativemethylation-specificPCR,q MSP)检测血浆HOXA7甲基化水平,电化学发光检测血浆CEA、CA199和Cyfra21-1水平。构建受试者工作特征曲线(ROC)分析各指标鉴别NSCLC的临床价值,并分析HOXA7甲基化与临床病例参数、肿瘤标志物之间的关系。结果:与健康对照组相比,NSCLC患者血浆中HOXA7基因甲基化水平异常增高(χ^2=36.972,P<0.0001),HOXA7甲基化诊断NSCLC的敏感度为68.8%(55/80),特异度为86.0%(43/50)。血浆HOXA7甲基化与性别、年龄、有无吸烟史和病理类型无关(均P>0.05),但与TNM分期有关(P<0.05),其中Ⅳ期患者血浆HOXA7甲基化水平最高。肿瘤标志物中Cyfra21-1诊断NSCLC的价值最高,敏感度为70.00%,特异度为90.00%。HOXA7甲基化联合三指标诊断NSCLC的效能最高(AUC=0.893,敏感度73.75%,特异度94%)。HOXA7甲基化与Cyfra21-1的相关系数最高(r=0.564,P<0.05)。结论:HOXA7基因甲基化水平对NSCLC的诊断有一定价值,与NSCLC的恶性程度相关,联合肿瘤标志物检测可以提高NSCLC的诊断效能。

Clinical observation of raltitrexed/bevacizumab combined with irinotecan or oxaliplation for advanced colorectal cancer

Objective： The aim of the study was to investigate the efficacy and safety of raltitrexed/bevacizumab in combination with irinotecan or oxaliplation for advanced colorectal cancer as the second-line and second-line above treatments. Metho ods： Fifteen cases of advanced colorectal cancer were enrolled to receive regimens including raltitrexed/bevacizumab combined with irinotecan or oxaliplation. Two cases were treated with raltitrexed ＋ bavacizumab regimen, 9 cases with raltitrexed ＋ bavacizumab ＋ irinotecan regimen, and 4 cases with raltitrexed ＋ bevacizumab ＋ oxaliplation regimen. The doses of the drugs were as follows： bevacizumab 5 mg/kg ivgtt, d 1; raltitrexed 2.0 mg/m2 ivgtt 15 min, d2; irinotecan 180 mg/m2 ivgtt 1 h, d2; and oxaliplatin 85 mg/m2 ivgtt 2 h, d2. Two weeks was a cycle for each regimen. Results： The efficacy of the 15 patients could be evaluated. Two cases were in PR ,10 cases in SD, 3 cases in PD, the response rate was 13.3%, and the disease control rate was 80.0%. The median progress-free survival was 5.1 months （95% CI： 3.404-6.813 months）, and the median overall survival was 11.5 months （95% CI： 8.985-13.930 months）. The adverse effects included anorexia, nausea/vomiting, fatigue, leucopenia, thrombocytopenia, etc, and the main 3-4 grades adverse effects were anorexia, nausea/vomiting, fatigue, and thrombocytopenia. Conclusion： Raltitrexed/bevacizumab combined with irinotecan or oxaliplatin as the secondline and second-line above treatments for advanced colorectal cancer has high disease control rates, and the adverse effect is well tolerated. The combined regimen can be recommended as a phase III clinical research and second-line and secondlines above treatments for advanced colorectal cancer.

Trial of the correlation between cytochrome oxidase CYP3A4 with the susceptibility of paclitaxel-based regimen for advanced gastric cancer

Objective: The aim of the study was to investigate the relationship between susceptibility of paclitaxel-based regimen and gene polymorphisms of cytochrome oxidase CYP3A4 for advanced gastric cancer. Methods: Peripheral venous blood sample of 53 advanced gastric cancer patients were enrolled to test the mutation of CYP3A4 gene by denaturing high performance liquid chromatography(DHPLC) and DNA sequencing. The relation between the efficacy of paclitaxel-based regimen and CYP3A4 gene polymorphisms was further analyzed. Results: DHPLC indicated that among the 53 patients, 21 cases showed biomodal type(mutation) and 32 cases were of unimodal type(wild-type). Sequencing results showed that the deletion mutation was found at the 27 th basic group of C in exon 10 of CYP3A4 gene. The response rate(RR) and disease control rate(DCR) of wild-type group were 40.6% and 84.4%, while in mutation group they were 33.3% and 85.7%, respectively, with no significances between the two groups(P > 0.05). Of all 53 cases, the median progression-free survival(PFS) was 6.5 months(95% CI: 3.576–9.424 months), and the median overall survival(OS) was 11.0 months(95% CI: 6.955–15.045 months). The median PFS and OS in wild-type group had no differences compared with those in mutation group(7.0 months vs. 7.0 months, P > 0.05; 10.0 months vs. 14.0 months, P > 0.05). Between wild-type and mutation groups, the median PFS of patients applied with oxaliplatin containing regimen and the median OS in patients applied with/without oxaliplatin had no significant differences(P > 0.05), while the median PFS in patients received non-oxaliplatin regime had statistical differences(P = 0.024). The median PFS and OS in patients receiving 3-drug or 2-drug regimes had no correlation with CYP3A4 gene polymorphisms. The adverse effects in the two groups were mild, mainly in grades 1–2. The common adverse effects were anorexia, nausea/vomiting and leucopenia. Conclusion: Deletion mutation was located in the 27 th basic group of C in exon 10 of CYP3A4 gene. Paclitaxel-based regime has a trend to prolong the OS of advanced gastric cancer with mutation type.

Homocysteine and Alzheimer’s disease： a literature review

Increasing evidence in recent years sug-gests homocysteine （Hcy） is involved in the pathogene-sis of Alzheimer’s disease （AD）, and that modifying this risk factor may be an alternative approach to delaying or preventing onset of this disease. However, intervention studies uggest inconsistent effects of folic acid supple-mentation, with or without vitamin B12, on the prevention of incident AD. Studies with Hcy-lowering therapy show benefcial effects of B vitamins inpatients with mild cog-nitive impairment （MCI）, especially in those with high Hcy levels. Further studies are needed to confrm elevated Hcy levels as a potentially treatable risk factor for AD.

Rapid identification of full-length genome and tracing variations of monkeypox virus in clinical specimens based on mNGS and amplicon sequencing

The monkeypox virus(MPXV)has triggered a current outbreak globally.Genome sequencing of MPXV and rapid tracing of genetic variants will benefit disease diagnosis and control.It is a significant challenge but necessary to optimize the strategy and application of rapid full-length genome identification and to track variations of MPXV in clinical specimens with low viral loads,as it is one of the DNA viruses with the largest genome and the most AT-biased,and has a significant number of tandem repeats.Here we evaluated the performance of metagenomic and amplicon sequencing techniques,and three sequencing platforms in MPXV genome sequencing based on multiple clinical specimens of five mpox cases in Chinese mainland.We rapidly identified the full-length genome of MPXV with the assembly of accurate tandem repeats in multiple clinical specimens.Amplicon sequencing enables cost-effective and rapid sequencing of clinical specimens to obtain high-quality MPXV genomes.Third-generation sequencing facilitates the assembly of the terminal tandem repeat regions in the monkeypox virus genome and corrects a common misassembly in published sequences.Besides,several intra-host single nucleotide variations were identified in the first imported mpox case.This study offers an evaluation of various strategies aimed at identifying the complete genome of MPXV in clinical specimens.The findings of this study will significantly enhance the surveillance of MPXV.

新疆塔什库尔干野生动物自然保护区马可波罗盘羊潜在生态廊道识别

识别野生动物的适宜生境并在适宜生境之间构建生态廊道能够提高生境连通性,有利于加强种群间基因交流并缓解生境破碎化带来的不利影响。本研究基于生境适宜性评价结果确定了塔什库尔干野生动物自然保护区内马可波罗盘羊(Ovis polii)的核心生境斑块,运用廊道设计模型Linkage Mapper识别最低成本廊道并确定其优先级。结果表明,马可波罗盘羊适宜生境主要分布在保护区西北部,核心生境斑块少且破碎化明显,夏冬两季核心生境斑块均为28个,潜在生态廊道分别为45和47条。采用成本加权距离与欧几里得距离之比(CWD:EucD)以及成本加权距离与最低成本路径长度之比(CWD:LCP)两种度量方法评估了生态廊道的质量与重要性。以CWD:EucD来衡量,夏季质量最高的4条廊道分别是皮斯岭至帕日帕克、同库至马尔洋、科克吐鲁克至帕日帕克,以及哈尔努孜至同库;冬季质量最高的3条廊道分别是其克尔克尔至亚希洛夫、萨提曼至依西代尔、其克尔克尔至科克吐鲁克。CWD:LCP分析表明,夏季质量最高的廊道分别是哈尔努孜至阔克加尔和阔克加尔至马尔洋;冬季质量最高的廊道分别是爱勒米希至塔萨拉、沙尔比列西南至依西代尔。利用流中心性评估各核心生境斑块和廊道的重要性表明,帕日帕克、塔萨拉和马尔洋这三个斑块在促进马可波罗盘羊迁移扩散方面的贡献值最高。夏季皮斯岭至帕日帕克、同库至马尔洋和马拉特至其克尔克尔这3条廊道的贡献值最高;冬季爱勒米希至塔萨拉、沙尔比列至沙尔比列西南和铁尔布尔列至沙尔比列这3条廊道的贡献值最高,上述核心生境斑块和生态廊道在维持保护区马可波罗盘羊种群迁徙扩散中发挥着关键作用。此外,赞坎、沙尔比列等斑块虽然面积小、贡献值低,但起到了维持景观中重要斑块连通的踏脚石作用,其重要性也不可忽略。研究结果可为塔什库尔干野生动物保护区马可波罗盘羊有效保护、保护区功能区划优化以及当地基础建设项目的规划选址提供科学指导。

Daily snow water equivalent product with SMMR,SSM/I and SSMIS from 1980 to 2020 over China

The reliable knowledge of seasonal snow volume and its trend is very important to understand Earth’s climate system.Thus,a long-time snow water equivalent(SWE)dataset is necessary.This work presents a daily SWE product of 1980-2020 with a linear unmixing method through passive microwave data including SMMR,SSM/I and SSMIS over China after cross-calibration and bias-correction.The unbiased root-mean-square error of snow depth is about 5-7 cm,corresponding to 10-15 mm for SWE,when compared with stations measurements and field snow course data.The spatial patterns and trends of SWE over China present significant regional differences.The overall slope trend presented an insignificant decreasing pattern during 1980-2020 over China;however,there is an obvious fluctuation,i.e.a significant decrease trend during the period 1980-1990,an upward trend from 2005 to 2009,a significant downward trend from 2009 to 2018.The increase of SWE occurred in the Northeast Plain,with an increase trend of 0.2 mm per year.Whereas in the Hengduan Mountains,it presented a downward trend of SWE,up to−0.3 mm per year.In the North Xinjiang,SWE has an increasing trend in the Junggar Basin,while it shows a decreasing trend in the Tianshan and Altai Mountains.

The energy-efficient implementation of an adaptive-filtering-based QRS complex detection method for wearable devices

Electrocardiogram（ECG） can be used as a valid way for diagnosing heart disease.To fulfill ECG processing in wearable devices by reducing computation complexity and hardware cost,two kinds of adaptive filters are designed to perform QRS complex detection and motion artifacts removal,respectively.The proposed design achieves a sensitivity of 99.49% and a positive predictivity of 99.72%,tested under the MIT-BIH ECG database.The proposed design is synthesized under the SMIC 65-nm CMOS technology and verified by post-synthesis simulation.Experimental results show that the power consumption and area cost of this design are of 160 μW and 1.09×10^5 μm^2,respectively.

Two-Scale Picard Stabilized Finite Volume Method for the Incompressible Flow

In this paper,we consider a two-scale stabilized finite volume method for the two-dimensional stationary incompressible flow approximated by the lowest equalorder element pair P_(1)−P_(1)which do not satisfy the inf-sup condition.The two-scale method consist of solving a small non-linear system on the coarse mesh and then solving a linear Stokes equations on the fine mesh.Convergence of the optimal order in the H1-norm for velocity and the L^(2)-norm for pressure are obtained.The error analysis shows there is the same convergence rate between the two-scale stabilized finite volume solution and the usual stabilized finite volume solution on a fine mesh with relation h=O(H^(2)).Numerical experiments completely confirm theoretic results.Therefore,this method presented in this paper is of practical importance in scientific computation.

SALIRI-based(raltitrexed plus irinotecan)therapy as a second-line treatment for patients with metastatic colorectal cancer(SALLY):A prospective,multicenter,non-interventional,registry study

Primary chemotherapy options for colorectal cancer(CRC)involve four key drugs:fluorouracils(5-FU),oxaliplatin,irinotecan and raltitrexed.The first-line regimen consists of 5-FU and leucovorin combined with oxaliplatin(FOLFOX),while the second-line regimen involves 5-FU and leucovorin combined with irinotecan(FOLFIRI)for metastatic CRC(mCRC)in China[1].