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Yongli Zhang,1,2 Yanyan Niu,1,2 Hong Huo,1,2 Jian Wang,1,2 Xiaofeng Jin,1,2 Hua Yang1,2 1Peking Union Medical College, Chinese Academy of Medical Sciences, Peking Union Medical College Hospital, Department of Otolaryngology, Beijing, People’s Republic of China; 2Translational Medicine Center, Peking Union Medical College Hospital, Beijing, People’s Republic of ChinaCorrespondence: Jian Wang; Hua Yang, Department of Otolaryngology, Peking Union Medical College Hospital, Beijing, People’s Republic of China, 100730, Tel +13673164261 ; +13701127757, Fax +86-10-69156311, Email wangjianent@163.com; dr_yanghua2021@163.comPurpose: Biofilms on voice prostheses are important factors shortening their service life. Sodium selenite has been used to prevent and treat various diseases. Whether sodium selenite can inhibit and remove mature biofilms on voice prostheses is still unknown.Methods: To verify the effects of sodium selenite on mature mixed-bacteria biofilms (Staphylococcus aureus, Candida albicans, and Streptococcus faecalis) on voice prostheses, we used quantitative and qualitative methods, eg, real-time fluorescence quantitative PCR, crystal violet staining, 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) (XTT) reduction assays, and scanning electron microscopy, to measure the effects of sodium selenite on the number of bacterial colonies, biofilm formation ability, metabolic activity, and ultrastructure in a model of mature mixed-bacteria biofilms on voice prostheses and validated the effects in vitro on mature biofilms on voice prostheses from patients.Results: When exploring the possible mechanism of biofilm inhibition and removal by sodium selenite, we found that it significantly inhibited and removed biofilms on voice prostheses and effectively destroyed the spatial structure of the biofilms. The inhibition and removal effects became more significant with increasing sodium selenite concentrations.Conclusion: We demonstrated that sodium selenite can inhibit and remove biofilms of mature mixed strains on voice prostheses, providing a novel basis for treating patients’ voice prosthesis biofilms.Keywords: sodium selenite, voice prostheses, mature biofilms, mixed strains on voice prostheses, remove, inhibit

Zhang Y, Niu Y, Huo H, Wang J, Jin X, Yang H. Infect Drug Resist. 2022;15:7799–7810. The authors have advised that there was an error in the Funding section on page 7809. Line 2, the text “XDA1601040201” should read “XDA16040301”. The authors apologize for this error.

Weixin Zhang,1 ChunMiao Xu,2 Jianyu Guo,3 Limei Guo,2 Hongliang Huo,4 Huan Wang5 1Department of Nursing, Qiqihar Medical University, Qiqihar, 161000, China; 2Department of Nursing of Medicine and Surgery, Qiqihar Medical University, Qiqihar, 161000, China; 3Department of Orthopedics Surgery, The First Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, China; 4Department of Nursing, The Second Affiliated Hospital of Qiqihar Medical University, Qiqihar, 161000, China; 5Department of Community Nursing, Qingdao Health School of Shandong Province, Qingdao, 266000, ChinaCorrespondence: ChunMiao Xu Tel +86 452 2664572Email mismbi@hotmail.comObjective: Glioma (GM) is a common type of malignant and aggressive tumor in brain with poor prognosis. Circular RNAs (circRNAs) are well-known regulators in cancer progression. However, its molecular basis in GM remains to be investigated.Materials and Methods: CircRNA microarray was used to detect differentially expressed circRNAs in GM and matched noncancerous tissues. qRT-PCR was applied to detect the expression profile of circ-ELF2 in GM tissue specimens and cell lines. CCK-8, clone formation, AO/EB staining, flow cytometry, wound healing, and transwell assays were performed to identify the functions of circ-ELF2 in GM cells. The distribution of circ-ELF2 was analyzed by RNA-FISH and subcellular fractionation assay. Dual-luciferase reporter assay was applied to verify the predicted binding sites between miR-510-5p and circ-ELF2/MUC15 3ʹ-UTR. Rescue assay was finally conducted to explore whether the oncogenic role of circ-ELF2 was partially attributed to miR-510-5p/MUC15 signaling.Results: We observed that circ-ELF2 was significantly upregulated in GM tissues, which was analyzed by circRNA microarray and qRT-PCR. Upregulation of circ-ELF2 was associated with poor prognosis and high recurrence rate for GM patients after surgery. The collapse of circ-ELF2 caused growth arrest and downregulation of cell migratory and invasive potential of GM cells and promoted cell apoptosis. In contrast, elevated expression of circ-ELF2 led to the opposite effect. Mechanistically, circ-ELF2 acted as a competing endogenous RNA (ceRNA) for miR-510-5p to positive modulate MUC15 expression at posttranscriptional level. Circ-ELF2 upregulated MUC15 by sponging miR-510-5p, thus promoting GM growth and aggressiveness.Conclusion: This study indicates that circ-ELF2/miR-510-5p/MUC15 signaling plays a key role in promoting the occurrence and development of GM.Keywords: glioma, circRNA, circ-ELF2, miR-510-5p, MUC15

Lu Cao,1 Peng Qin,2 Jianjiang Zhang,1 Huiju Qiao,1 Peipei Shi,1 Huali Huo1 1Department of Pediatrics, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, People’s Republic of China; 2Department of Cancer Immunotherapy, The Affiliated Cancer Hospital of Zhengzhou University, Zhengzhou, Henan 450000, People’s Republic of ChinaCorrespondence: Lu Cao Email caolu_mailtowe@163.comBackground: Renal fibrosis is a frequent pathway leading to end-stage kidney dysfunction. In addition, renal fibrosis is the ultimate manifestation of chronic kidney diseases (CKD). Long noncoding RNAs (lncRNAs) are known to be involved in occurrence of renal fibrosis, and lncRNA plasmacytoma variant translocation 1 (PVT1) has been reported to act as a key biomarker in renal diseases. However, the role of PVT1 in renal fibrosis remains unclear.Materials and Methods: HK-2 cells were treated with TGF-β 1 to mimic renal fibrosis in vitro. Gene and protein expressions in HK-2 cells were measured by qRT-PCR and Western-blot, respectively. ELISA was used to test the level of creatinine (CR) and blood urea nitrogen (BUN) in serum of mice. Additionally, unilateral ureteral obstruction (UUO)-induced renal fibrosis mice model was established to investigate the effect of PVT1 on renal fibrosis in vivo.Results: PVT1 was upregulated in TGF-β 1-treated HK-2 cells. In addition, TGF-β 1-induced upregulation of α-SMA and fibronectin in HK-2 cells was significantly reversed by PVT1 knockdown. Meanwhile, PVT1 bound to miR-181a-5p in HK-2 cells. Moreover, miR-181a-5p directly targeted TGF-βR1. Furthermore, miR-181a-5p antagonist could significantly reverse the anti-fibrotic effect of PVT1 knockdown. Besides, knockdown of PVT1 notably attenuated the symptom of renal fibrosis in vivo.Conclusion: Knockdown of PVT1 significantly inhibited the progression of renal fibrosis in vitro and in vivo. Thus, PVT1 may serve as a potential target for the treatment of renal fibrosis.Keywords: PVT1, renal fibrosis, miR-181a-5p, TGF-βR1

Yanfang Liu, Hua Huo, Zhibo Zhao, Wenli Hu, Yujia Sun, Yunbiao Tang Technical Center for Clinical Pharmacy, Department of Drug Clinical Trail Management Agency, General Hospital of Shenyang Military Area Command, Shenyang, China Aim: This study developed a high-performance liquid chromatography–tandem mass spectrometry method to simultaneously determine the concentrations of flupirtine and its major active metabolite D-13223 in human plasma in order to assess the bioequivalence (BE) of two flupirtine maleate capsules among healthy male Chinese volunteers under fasting and fed conditions. Materials and methods: There were two single-center, randomized, single-dose, open-label, laboratory-blinded, two-period, cross-over studies which included 24 healthy male Chinese volunteers under fasting and fed conditions, respectively. Plasma samples were collected prior to and up to 48 h after dosing. The concentrations of flupirtine and its major active metabolite D-13223 in plasma samples were determined by a validated method, that is, high-performance liquid chromatography coupled with a tandem mass spectrometry detector. Pharmacokinetic metrics of area from time zero to the last measurable concentration (AUC0-t), area under the plasma concentration–time curve from administration to infinite time (AUC0-∞), and Cmax were used for BE assessment. Results: Forty-eight healthy volunteers who met the criteria were enrolled and completed the study. According to the observation of vital signs and laboratory measurement, no volunteers had any adverse reactions. Under fasting condition, the geometric mean ratios (90% CI) of the test/reference drug for flupirtine were 103.0% (98.1%–108.2%) for AUC0-t, 102.9% (98.2%–107.9%) for AUC0-∞, and 97.0% (85.9%–109.5%) for Cmax. Under fed condition, the geometric mean ratios (90% CI) of the test/reference drug for flupirtine were 101.7% (98.4%–105.1%) for AUC0-t, 101.6% (98.5%–104.8%) for AUC0-∞, and 103.5% (94.7%–113.0%) for Cmax. The difference between test and reference formulations, Tmax, was not statistically significant. The 90% CIs of the test/reference AUC ratio and Cmax ratio of D-13223 were also within the acceptance range for BE both under fasting and fed conditions. Conclusion: The two formulations of flupirtine maleate capsule were bioequivalent (the test and the reference products) under fasting and fed conditions, and thus both can be used interchangeably in the clinical setting. Keywords: flupirtine, D-13223, LC–MS/MS

Autonomous experimentation driven by artificial intelligence (AI) provides an exciting opportunity to revolutionize inorganic materials discovery and development. Herein, we review recent progress in the design of self-driving laboratories, including robotics to automate materials synthesis and characterization, in conjunction with AI to interpret experimental outcomes and propose new experimental procedures. We focus on efforts to automate inorganic synthesis through solution-based routes, solid-state reactions, and thin film deposition. In each case, connections are made to relevant work in organic chemistry, where automation is more common. Characterization techniques are primarily discussed in the context of phase identification, as this task is critical to understand what products have formed during synthesis. The application of deep learning to analyze multivariate characterization data and perform phase identification is examined. To achieve "closed-loop"materials synthesis and design, we further provide a detailed overview of optimization algorithms that use active learning to rationally guide experimental iterations. Finally, we highlight several key opportunities and challenges for the future development of self-driving inorganic materials synthesis platforms.

Collecting and analyzing the vast amount of information available in the solid-state chemistry literature may accelerate our understanding of materials synthesis. However, one major problem is the difficulty of identifying which materials from a synthesis paragraph are precursors or are target materials. In this study, we developed a two-step chemical named entity recognition model to identify precursors and targets, based on information from the context around material entities. Using the extracted data, we conducted a meta-analysis to study the similarities and differences between precursors in the context of solid-state synthesis. To quantify precursor similarity, we built a substitution model to calculate the viability of substituting one precursor with another while retaining the target. From a hierarchical clustering of the precursors, we demonstrate that the "chemical similarity"of precursors can be extracted from text data. Quantifying the similarity of precursors helps provide a foundation for suggesting candidate reactants in a predictive synthesis model.

Digitizing large collections of scientific literature can enable new informatics approaches for scientific analysis and meta-analysis. However, most content in the scientific literature is locked-up in written natural language, which is difficult to parse into databases using explicitly hard-coded classification rules. In this work, we demonstrate a semi-supervised machine-learning method to classify inorganic materials synthesis procedures from written natural language. Without any human input, latent Dirichlet allocation can cluster keywords into topics corresponding to specific experimental materials synthesis steps, such as “grinding” and “heating”, “dissolving” and “centrifuging”, etc. Guided by a modest amount of annotation, a random forest classifier can then associate these steps with different categories of materials synthesis, such as solid-state or hydrothermal synthesis. Finally, we show that a Markov chain representation of the order of experimental steps accurately reconstructs a flowchart of possible synthesis procedures. Our machine-learning approach enables a scalable approach to unlock the large amount of inorganic materials synthesis information from the literature and to process it into a standardized, machine-readable database.

CABYR is a protein that regulates calcium-binding tyrosine phosphorylation located in sperm flagella, which increases significantly during sperm capacitation and is primarily involved in sperm capacitation and motility. This study aimed to analyze the expression regulation pattern, sequence characteristics and potential biological function of CABYR gene in Banna mini-pig inbred line (BMI). The testes of adult BMI boars were used for RNA-seq; the complete coding sequence of CABYR was cloned; the sequence, structural characteristics, interacting proteins, KEGG and GO of CABYR were analyzed; the ceRNA regulatory network of CABYR was built using RNA-seq data. The average expression level and TPM value of CABYR gene obtained by RNA-seq was 11 187.50 and 225.29, respectively. The full-length CDS of CABYR was 1149 bp (GenBank accession number: OK042309) encoding 382 amino acids (GenBank login number: UYO37316). The amino acid sequence alignment analysis of multiple species revealed that the similarity between BMI and other species exceeded 73%, indicating a relatively conserved sequence. The CABYR protein was found to contain the DD_CABYR_SP17 conserved domain, the results of species phylogenetic tree analysis met the clustering criteria. Other analyses, including protein-protein interaction (PPI) networks, KEGG, and GO, revealed that BMI CABYR interacts with 50 proteins involved in a variety of functions, such as sexual reproduction and reproductive processes. CABYR was involved in 7 GOs, including five cellular components, one molecular functions, and one biological processes, according to functional annotation. Six miRNAs were found to regulate the CABYR gene via targeted interactions. Additionally, 8, 6, and 1 lncRNAs were found to interact with ssc-miR-4331-3p, ssc-miR-744, and ssc-miR-491, respectively, in association with CABYR. This study examines the expression of CABYR in the testis of BMI, as well as its molecular structure characteristics and expression regulatory network. These findings provide a foundation for future research on the involvement of the CABYR gene in spermatogenesis processes in BMI pigs, particularly in relation to crucial biological processes such as sperm motility and fibrous sheath development. [ABSTRACT FROM AUTHOR]

Substantial anthropogenic emissions from China have resulted in serious air pollution, and this has generated considerable academic and public concern. The physical transport of air pollutants in the atmosphere has been extensively investigated; however, understanding the mechanisms how the pollutant was transferred through economic and trade activities remains a challenge. For the first time, we quantified and tracked China's air pollutant emission flows embodied in interprovincial trade, using a multiregional input - output model framework. Trade relative emissions for four key air pollutants (primary fine particle matter, sulfur dioxide, nitrogen oxides and non-methane volatile organic compounds) were assessed for 2007 in each Chinese province. We found that emissions were significantly redistributed among provinces owing to interprovincial trade. Large amounts of emissions were embodied in the imports of eastern regions from northern and central regions, and these were determined by differences in regional economic status and environmental policy. It is suggested that measures should be introduced to reduce air pollution by integrating cross-regional consumers and producers within national agreements to encourage efficiency improvement in the supply chain and optimize consumption structure internationally. The consumption-based air pollutant emission inventory developed in this work can be further used to attribute pollution to various economic activities and final demand types with the aid of air quality models.

Designing a reasonable M/G/1 retrial queue system that enhances service efficiency and reduces energy consumption is a challenging issue in Information and Communication Technology systems. This paper presents an M/G/1 retrial queue system incorporating random working vacation (RWV) and improved service efficiency during vacation (ISEV) policies, and examines its optimal queuing strategies. The RWV policy suggests that the server takes random working vacations during reserved idle periods, effectively reducing energy consumption. In contrast, the ISEV policy strives to augment service efficiency during regular working periods by updating, inspecting or maintaining the server on vacations. The system is transformed into a Cauchy problem to investigate its well-posedness and stability, employing operator semigroup theory. Based on the system's stability, steady-state performance measures, such as service efficiency, energy consumption and expected costs, are quantified using the steady-state solution. The paper subsequently demonstrates the existence of optimal queuing strategies that achieve maximum efficiency and minimum expected costs. Finally, two numerical experiments are provided to illustrate the effectiveness of the system. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aimed to systematically evaluate the effect of whole-body vibration (WBV) training on the improvement of limb function in patients with Parkinson's disease (PD). MATERIALS AND METHODS: An electronic search was performed on the databases, including PubMed, Web of Science, Scopus, SCI-hub, ScienceDirect, Embase, IEEE, Medline, Wiley, ClinicaIKey, CNKI, Wanfang, VIP database, Chinese Medical Association, and CBM Database from inception to May 2022 to collect randomized controlled studies on whole-body vibration training for patients with Parkinson's disease. Two researchers independently screened the literature, extracted the data, and evaluated the quality of the literature, then used Review-Manager 5.4 software for quantitative statistical analysis, including heterogeneity test, sensitivity analysis, risk of bias assessment, combined outcome index effect size and effect size inspection. RESULTS: A total of 9 studies were included in the meta-analysis, including 346 patients, 174 patients in the control group and 172 patients in the observation group. Meta-analysis results showed that, compared with conventional physical therapy or drug therapy alone, whole-body vibration reduced the Unified Parkinson's Disease Rating Scale (UPDRSIII) score and significantly improved the motor function of patients with Parkinson's disease [MD=-2.39, 95% CI (-4.41, -0.37), Z=2.14 (p=0.23)]. Moreover, whole-body vibration significantly improved the walking stability of Parkinson's patients [MD=- 1.96, 95% CI (-2.71- -1.21), Z=1.17 (p=0.03)]. However, its improvement in balance ability [MD=- 0.06, 95% CI (-0.77, 0.65), Z=1.07 (p=0.19)] and daily living ability [MD=0.03, 95% CI (-1.68, 0.74), Z=0.24 (p=0.87)] of patients, it was not t statistically significant. CONCLUSIONS: Compared with conventional therapy, WBV has certain advantages in improving the balance function and gait performance of PD patients, but the effect on balance ability and daily living ability is not significant. Thus, more high-quality research is required for further verification. [ABSTRACT FROM AUTHOR]

Objective The 509 Daobanxi deposit in the West Kunlun orogenic belt is a newly discovered large pegmatite-type lithium-polymetallic deposit in northwestern China. As a typical granite pegmatite lithium deposit in the region, the metallogenic characteristics and pegmatite evolution of the 509 Daobanxi deposits are of great significance for understanding the entire lithium-polymetallic mineralization process of the West Kunlun metallogenic belt. The granite pegmatites contain assemblages of plagioclase, spodumene, quartz, muscovite, etc., exhibiting strong mylonization and forming typical ductile deformation characteristics in the 509 Daobanxi deposit. Quartz, an essential mineral in granite pegmatite, is ideal for tracking pegmatite's mineralization process and studying the deformation behavior of continental rocks in long-term geological history. Methods To study the late-stage emplacement process of pegmatite evolution, comprehensive analyses were conducted on the quartz deformation structures measurements, fluid inclusion temperature, and quartz trace elements for the 509 Daobanxi granite pegmatites. Cathodoluminescence (CL) analysis of quartz in deformed granite pegmatite samples was performed to reveal the compositional zoning of Ti in quartz. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to analyze 64 points from samples Zk2707-9 and Zk1107-2. Results The minerals of spodumene and plagioclase in deformed pegmatites primarily show brittle fracturing characteristics, with the features of rigid body deformation and the muscovite presence of mica-fish. Meanwhile, the conspicuous feature is that quartz grains mainly develop dynamic recrystallization and contain subgranis. According to the microstructural characteristics of spodumene, plagioclase, and quartz, the deformation temperature of mylonitized granite pegmatite is 300~400℃. The CL images of quartz bands in the granite pegmatite samples have no apparent zoning, indicating that the Ti content reaches a relative equilibrium state in the quartz deformation stage. The LA-ICP-MS analysis shows quartz from the 509 Daobanxi granite pegmatites contains a lower concentration of Ti (1.03 ×10−6 to 7.67×10−6 and 1.04 ×10−6 to 6.75×10−6), suggesting relatively lower deformation temperatures. The Ti-in-quartz thermobarometry indicates quartz deformation temperatures ranging from 371 to 398°C and 351 to 377°C, respectively. The thermometric measurement shows that homogenization temperatures of the quartz fluid inclusions in pegmatite varied from 260℃ to 283℃, likely recording the temperature of the late stage of pegmatite evolution. Conclusion Comprehensive analysis shows that the 509 Daobanxi granite pegmatites underwent a period of intense ductile deformation during the emplacement process, with low temperature and high strain rate. The emplacement of pegmatite is a product of the rapid cooling process, and the grain size reduction caused by dynamic recrystallization (GBM) under high-stress and low-temperature conditions profoundly changed the rheological properties of pegmatite. The supercooling process from ~400℃ to ~260℃ (ΔT=140℃±), resulting in less rapid mineral crystalline new nuclei in pegmatites, is more conducive to the formation of coarse quartz and other mineral particles, forming the significant characteristics of granite pegmatites. [ Significance ]In fact, the emplacement process of granitic pegmatites remains a puzzle, and high-quality, accurate systematic work is needed to understand the evolution process and behavior of granite pegmatite. By studying the 509 Daobanxi granite pegmatites, we proposed that the pegmatite emplacement was a product of the rapid cooling process, and supercooling plays an essential role in pegmatite emplacement. Similar deformation characteristics are widely developed in the Tugeman lithium deposit in the Altyn Tagh area and the Jiajika lithium deposit in the western Sichuan. Although the current work is preliminary, our study provides some clues for exploring the emplacement process of granitic pegmatites.

Abstract The objective of this research is to examine the impact of eccentric training on hamstring flexibility and strength in young dancers during the concluding stages of their foundational dance training program. A total of 24 female, second-year dance students from Hebei Normal University were selected as participants. They were divided into three distinct groups: Nordic hamstring exercise and single-leg deadlift group (NHE&SLD), forward bending exercises and standing leg lift group (FBE&SLL), and a control group (CG). The study was designed around a 6-week training regimen. An isokinetic dynamometer was used to measure seated knee flexor–extensor strength, while electronic goniometry was employed to measure hamstring flexibility in the supine position. Paired sample t-tests were conducted within each group, and one-way analysis of covariance (ANCOVA) was utilized for comparisons between groups. In the NHE&SLD group, significant disparities were observed in both concentric (T = − 5.687, P = 0.001) and eccentric (T = − 3.626, P = 0.008) hamstring strength pre and post-intervention. The pre-intervention dominant leg concentric strength test values significantly influenced the post-intervention outcomes (F = 5.313, P = 0.001, η2 = 0.840). Similarly, the pre-intervention dominant leg eccentric strength test values impacted the post-intervention results (F = 4.689, P = 0.043, η2 = 0.190). Following the intervention, the NHE&SLD group displayed marked changes in the active straight leg raising angle on both left (T = − 4.171, P = 0.004) and right (T = − 6.328, P = 0.001) sides. The FBE&SLL group also revealed significant changes in the active straight leg raising angle on both left (T = − 4.506, P = 0.003) and right (T = − 4.633, P = 0.002) sides following the intervention. The pre-intervention left leg concentric strength test value significantly influenced the post-intervention outcomes (F = 25.067, P = 0.001, η2 = 0.556). Likewise, the pre-intervention right leg eccentric strength test value significantly influenced the post-intervention results (F = 85.338, P = 0.01, η2 = 0.810). Eccentric training can better enhance the flexibility and strength of hamstring muscles in dance students. Traditional stretching training significantly improves the flexibility of the hamstring muscles. Eccentric training has more training benefits than traditional stretching training. It is recommended for dance students to use eccentric training when increasing hamstring flexibility and strength.

Mass customization (MC) is a crucial strategy for manufacturers to gain competitive advantages. Enterprise resource planning (ERP) systems are widely adopted in manufacturing. This study applied the dynamic capabilities view (DCV) to explore how firms leverage ERP systems to facilitate the implementation of MC. This study examined the effect of ERP assimilation (ERPA) and organizational agility (OA) on mass customization capability (MCC), the mediating role of OA, and the moderating role of absorptive capacity (AC). Data were collected using a self-administered questionnaire survey that yielded 166 responses in Jiangsu province, China. The partial least square structural equation modelling (PLS-SEM) approach was employed to test the study hypotheses. Results revealed that ERPA affects OA, and OA also affects MCC. However, no significant relationship was found between ERPA and MCC. Again, data supported the mediating effect of OA between ERPA and MCC and the moderating effect of AC between ERPA and OA.

The lightweight high entropy alloys have shown great application value in the lightweight structural materials. Laser melting and laser additive manufacturing technology provide new ideas for the development of high entropy alloys due to their extreme metallurgical conditions. AlxNbTiV(x=0.5-7) and AlNbTiyV(y=1-7) button samples were prepared by laser melting technology, and their phase structure, microstructure and hardness were systematically studied. The results show that the Al content has a significant effect on the phase structure and microstructure of the alloy. When the Al content is low (x ≤ 2), the AlxNbTiV alloy is composed of BCC single-phase solid solution. When the Al content is high (2 ≤ x ≤ 7), intermetallic compounds appear in the alloy. With the increase of Al content, the BCC and TiAl phases change into TiAl3 and NbAl3 phases. Ti content in a certain range (y ≤ 7) will not affect the phase structure of the alloy. AlNbTiyV alloys are composed of BCC single-phase solid solution. The content of Al and Ti has a great influence on the hardness of the alloy. When the AlxNbTiV alloy is composed of BCC single phase, the hardness of the alloy increases with the increase of Al content, and the appearance of intermetallic compounds makes the hardness of the alloy no longer change with the change of Al content. The hardness of AlNbTiyV alloy decreases with the increase of Ti content.

The Daikai Station, a cut and cover structure in the subway system in Kobe, collapsed during the Hyogoken-Nambu earthquake of January 17, 1995 in Japan. The Daikai Station is the first well-documented underground structure not crossing an active fault that has completely collapsed during an earthquake without liquefaction of the surrounding soil. What makes this case even more interesting is that tunnel sections adjacent to the station, with similar structural characteristics and analogous soil conditions, did not collapse. Dynamic numerical analyses have been conducted to investigate the load transfer mechanisms between the underground structure and the surrounding soil and to identify the causes for different behavior of similar sections of the station subjected to the same seismic loading. A hysteretic nonlinear soil model has been used for the analysis. The model captures well the soil's shear modulus degradation and the increase of damping with strain. The results from the analyses show that, for a given earthquake, there are two key factors that determine the response of an underground structure: the relative stiffness between the structure and the degraded surrounding ground, and the frictional characteristics of the interface. A stiff structure has small deformations; because the adjacent soil movement is restricted by the structure, the shear modulus degradation of the soil is limited which contributes to reduce further deformation of the soil and thus decreases the displacement demand on the structure. A strong interface is capable of transmitting larger shear to the structure but in turn increases the confinement of the soil surrounding the structure which limits the soil's shear modulus degradation. The model predicts larger deformations in the section that collapsed because this section had a smaller stiffness, and thus triggered drifts in critical structural elements which were larger than at other sections of the station which remained stable. CE Database subject headings: Soil-structure interaction; Underground structures; Seismic design; Stiffness; Shear modulus; Degradation; Load transfer; Japan; Earthquakes.