859 results on '"Xiaochun LIU"'
Search Results
2. Drug resistance mutation analysis of HIV-1 among blood donors in Dalian: 2011—2020
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Xiaohan GUO, Xuelian DENG, Xiaochun LIU, Yingying WANG, Liang ZANG, and Jun ZHOU
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hiv-1 ,drug resistance mutation ,blood donor ,Diseases of the blood and blood-forming organs ,RC633-647.5 ,Medicine - Abstract
Objective To study the distribution and trend of HIV-1 drug resistance mutation in Dalian blood donors between 2011 and 2020. Methods The protease-reverse transcriptase (PR-RT) region was sequenced in Dalian blood donors tested HIV-1 positive between 2011 and 2020. Drug resistance mutation (DRM) rate and level of resistance to selected drugs were analyzed by the Stanford HIV Drug Resistance Database. Results DRM were detected in 17.2% (30/174) of samples, while transmitted drug resistance (TDR) was 5.7% (10/174). Between 2011 and 2020, DRM and TDR rates increased significantly in 2019 and reached their highest levels in 2020 (44.4% and 22.2%, respectively). DRM carriage was associated with people with college degree or above and with local residents (P
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- 2024
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3. On Kirchhoff type problems with singular nonlinearity in closed manifolds
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Nanbo Chen, Honghong Liang, and Xiaochun Liu
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kirchhoff equations ,singularity ,critical exponent ,closed manifolds ,variational methods ,Mathematics ,QA1-939 - Abstract
This paper dealt with a class of Kirchhoff type equations involving singular nonlinearity in a closed Riemannian manifold $ (M, g) $ of dimension $ n\ge3 $. Existence and uniqueness of a positive weak solution were obtained under certain assumptions with the help of the variation methods and some analysis techniques.
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- 2024
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4. A new probabilistic model with mixed-state failure rates: Modeling time-to-event scenarios in reliability and music engineering
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Xiaochun Liu, Jian Ji, Afaf Alrashidi, Fatimah A. Almulhim, Etaf Alshawarbeh, and Jin-Taek Seong
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Flexible Weibull distribution ,New beta power transformed method ,Estimation ,Engineering ,Music engineering ,Applications ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
We consider and implement a new contemporary and state-of-the-art probabilistic model with optimal data modeling capabilities. We call the present probabilistic model a new beta power flexible Weibull distribution. It is obtained by using the flexible Weibull distribution together with the new beta power transformed method. The flexibility of the new model is explored visually. The visual inspection shows that the proposed model captures many important forms (or shapes) of its density and hazard rate function. For the new beta power flexible Weibull distribution, the point estimators are derived mathematically and numerically (using practical data sets). Additionally, simulation studies are also exercised to show that these point estimators are efficient and consistent. Ultimately, three data sets are taken into account to certify the optimality and relevance of the new model. Among the data sets, the first two applications are picked from reliability engineering and the third data set is observed from music engineering. Regarding the fitting of these three data sets, taking into consideration for statistical tests, it is distinguished that the new model persistently outstrips the rival distributions.
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- 2024
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5. Overcoming strength-ductility tradeoff with high pressure thermal treatment
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Yao Tang, Haikuo Wang, Xiaoping Ouyang, Chao Wang, Qishan Huang, Qingkun Zhao, Xiaochun Liu, Qi Zhu, Zhiqiang Hou, Jiakun Wu, Zhicai Zhang, Hao Li, Yikan Yang, Wei Yang, Huajian Gao, and Haofei Zhou
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Science - Abstract
Abstract Conventional material processing approaches often achieve strengthening of materials at the cost of reduced ductility. Here, we show that high-pressure and high-temperature (HPHT) treatment can help overcome the strength-ductility trade-off in structural materials. We report an initially strong-yet-brittle eutectic high entropy alloy simultaneously doubling its strength to 1150 MPa and its tensile ductility to 36% after the HPHT treatment. Such strength-ductility synergy is attributed to the HPHT-induced formation of a hierarchically patterned microstructure with coherent interfaces, which promotes multiple deformation mechanisms, including dislocations, stacking faults, microbands and deformation twins, at multiple length scales. More importantly, the HPHT-induced microstructure helps relieve stress concentration at the interfaces, thereby arresting interfacial cracking commonly observed in traditional eutectic high entropy alloys. These findings suggest a new direction of research in employing HPHT techniques to help develop next generation structural materials.
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- 2024
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6. Anomalous {101¯2} tensile twinning and subsequent detwinning in a friction stir processed carbon fiber-reinforced Mg composite
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Wei Zhao, Zhihao Jiang, Xiang Wu, Yujing Liu, Haokun Yang, Jun Wang, Qi Liu, and Xiaochun Liu
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Mining engineering. Metallurgy ,TN1-997 - Published
- 2024
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7. Temperature-dependent electroplasticity in the Invar 36 alloy
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Hongrui Dong, He Zhou, Yong Li, Xiaoqiang Li, Shiteng Zhao, Xiaochun Liu, and Yaxin Wang
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Electroplasticity ,EBSD ,Recovery ,Plastic deformation ,Grain boundary ,Mining engineering. Metallurgy ,TN1-997 - Abstract
Electroplasticity of the Invar 36 alloy is investigated based on comparisions between warm and electrically-assisted (EA) uniaxial tensions experiments at different temperatures (100–600 °C) and corresponding microstructural characterizations. Under warm deformation (WD), the flow stress decreases with the increase in temperature, which is directly attributed to dynamic recovery and dynamic recrystallization. With the introduction of high electric current during deformation, it shows a temperature-dependent electroplasticity phenomenon. No difference could be observed between WD and EA samples below a critical temperature of 500 °C, above which, an obvious softening behavior takes place in EA samples. This transition in softening respective to deformation temperature clearly demonstrated that it correlates with the intrinsic current-induced dislocation annihilation and recovery rather than the traditional theory of the Joule heating effect. Our findings shed more light on the utilization of EA softening effect on the development of novel forming routines, especially for materials with limited deformability.
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- 2024
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8. Storage of plasma-derived exosomes: evaluation of anticoagulant use and preserving temperatures
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Caiting Yang, Jie Han, Hai Liu, Yuyu He, Zhenhua Zhang, Xiaochun Liu, Farooq Waqas, Lizhong Zhang, Huiping Duan, Jing He, and Li Dong
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exosome ,anticoagulant ,plasma ,temperature ,duration ,Diseases of the blood and blood-forming organs ,RC633-647.5 - Abstract
AbstractExosomes carry large cargo of proteins, lipids, and nucleic acids, serving as versatile biomarkers for disease diagnosis and vehicles for drug delivery. However, up to date, no well recognized standard procedures for exosome storage were available for clinical application. This study aimed to determine the optimal storage conditions and the anticoagulants for plasma-derived exosome isolation. Fresh whole blood samples were collected from healthy participants and preserved in four different anticoagulants including sodium citrate (SC1/4), sodium citrate (SC1/9), lithium heparin (LH), or Ethylenediamine tetraacetic acid (EDTA), respectively. Exosomes were extracted from the plasma by differential ultracentrifugation and stored at three different temperatures, 4°C, −20°C or − 80°C for a duration ranging from one week to six months. All plasma samples for storage conditions comparison were pretreated with LH anticoagulant. Exosome features including morphological characteristics, pariticles size diameter, and surface protein profiles (TSG101, CD63, CD81, CD9, CALNEXIN) were assessed by transmission electron microscopy, Nanoparticle Tracking Analysis, and Western Blotting, respectively. Exosomes preserved in LH and SC1/4 group tended to remain intact microstructure with highly abundant protein biomarkers. Exosomes stored at 4°C for short time were prone to be more stable compared to thos at −80°C. Exosomes stored in plasma were superior in terms of ultrastructure, size diameter and surface protein expression to those stored in PBS. In conclusion, plasma-dervied exosome characteristics strictly depend on the anticoagulants and storage temperature and duration.
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- 2024
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9. Efficacy of probiotic supplements on Parkinson's disease: A systematic review and meta-analysis
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Xiaxia Jin, Wendi Dong, Kaile Chang, Yongmei Yan, and Xiaochun Liu
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Parkinson's disease ,Probiotics ,Meta-analysis ,Constipation ,Efficacy ,Other systems of medicine ,RZ201-999 - Abstract
Objective: This study aimed to evaluate the clinical efficacy and safety of probiotics supplementation in the treatment of Parkinson's disease (PD). Methods: We searched China National Knowledge Infrastructure (CNKI), Weipu (VIP) database, Wanfang Database, Sinomed (CBM), PubMed, Embase, Cochrane library and Web of Science databases for eligible studies from inception to January 4th, 2024. Randomized controlled trials (RCTS) comparing the effects of probiotic supplements and placebo in patients with PD. Meta-analysis was conducted with the software Review Manager 5.4. The quality assessment was performed according to Cochrane risk of bias tool. Results: A total of 11 RCTs with 756 PD patients were included in this study. We found that probiotics could increase the number of complete bowel movements (CBMs) per week and improved the scores of Patient Assessment of Constipation Quality of Life Questionnaire (PAC-QOL) (SMD = 0.73, 95 % CI: 0.54 to 0.92, P 0.05, I2 = 98 %, respectively). In terms of PD composite scale scores: after treatment, there was no significant difference in Movement Disorder Society-Unified-Parkinson Disease Rating Scale Ⅲ score (MDS-UPDRSⅢ) between the probiotic group and the placebo group (SMD = − 0.09, 95 % CI: − 0.35 to 0.16, P > 0.05, I2 = 0 %). Conclusions: In conclusion, based on the overall results of the available RCTs studies, our results suggested the potential value of probiotics in improving constipation symptoms in PD patients. Therefore, probiotics may be one of the adjuvant therapy for PD-related constipation patients. The findings of this study provide more proof supporting the effectiveness of probiotics, encouraging probiotics to be utilized alone or in combination with other therapies in clinical practice for PD patients. However, more well-designed RCTs with large sample sizes are required.
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- 2024
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10. Single-cell analysis of uterosacral ligament revealed cellular heterogeneity in women with pelvic organ prolapse
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Xiaochun Liu, Minna Su, Lingyun Wei, Jia Zhang, Wenzhen Wang, Qian Hao, Xiling Lin, and Lili Wang
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Biology (General) ,QH301-705.5 - Abstract
Abstract Pelvic organ prolapse (POP) markedly affects the quality of life of women, including significant financial burden. Using single-cell RNA sequencing, we constructed a transcriptional profile of 30,452 single cells of the uterosacral ligament in POP and control samples, which has never been constructed before. We identified 10 major cell types, including smooth muscle cells, endothelial cells, fibroblasts, neutrophils, macrophages, monocytes, mast cells, T cells, B cells, and dendritic cells. We performed subpopulation analysis and pseudo-time analysis of POP primary cells, and explored differentially expressed genes. We verified previous cell clusters of human neutrophils of uterosacral ligaments. We found a significant reduction in receptor-ligand pairs related to ECM and cell adhesion between fibroblasts and endothelial cells in POP. The transcription factors related to the extracellular matrix, development, and immunity were identified in USL. Here we provide insight into the molecular mechanisms of POP and valuable information for future research directions.
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- 2024
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11. Chromosome-level genome assembly and annotation of the yellow grouper, Epinephelus awoara
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Weiwei Zhang, Yang Yang, Sijie Hua, Qingxin Ruan, Duo Li, Le Wang, Xi Wang, Xin Wen, Xiaochun Liu, and Zining Meng
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Science - Abstract
Abstract Epinephelus awoara, as known as yellow grouper, is a significant economic marine fish that has been bred artificially in China. However, the genetic structure and evolutionary history of yellow grouper remains largely unknown. Here, this work presents the high-quality chromosome-level genome assembly of yellow grouper using PacBio single molecule sequencing technique (SMRT) and High-through chromosome conformation capture (Hi-C) technologies. The 984.48 Mb chromosome-level genome of yellow grouper was assembled, with a contig N50 length of 39.77 Mb and scaffold N50 length of 41.39 Mb. Approximately 99.76% of assembled sequences were anchored into 24 pseudo-chromosomes with the assistance of Hi-C reads. Furthermore, approximately 41.17% of the genome was composed of repetitive elements. In total, 24,541 protein-coding genes were predicted, of which 22,509 (91.72%) genes were functionally annotated. The highly accurate, chromosome-level reference genome assembly and annotation are crucial to the understanding of population genetic structure, adaptive evolution and speciation of the yellow grouper.
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- 2024
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12. Seismic Energy Dissipation and Hysteresis Performances of Distinctly Shaped Steel-Reinforced Concrete Column–Beam Joints under Cyclic Loading
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Junquan Duan, Delei Yang, Xiaochun Liu, and Ping Xiang
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steel-reinforced concrete ,distinctly shaped column ,energy dissipation ,structure joint ,pseudo-static testing ,Building construction ,TH1-9745 - Abstract
The distinctly shaped steel-reinforced concrete (SRC) column–beam framing system offers an innovative and tailored structural solution that combines load-bearing capabilities with architectural esthetics. This study introduces an innovative joint design methodology, focusing on examining the seismic responsiveness of the uniquely designed SRC columns when interconnected with reinforced concrete (RC) beams, subjected to bidirectional low cycle loading patterns through precisely calibrated pseudo-static evaluations with varied stirrup spacing. A comparative assessment was undertaken, comparing the joints of SRC test specimens with their RC counterparts, ensuring equivalency in steel and reinforcement area to maintain fairness. The evaluation encompassed a thorough examination of hysteresis loop backbone curves, as well as load–strain hysteresis patterns. It was found that the specimens incorporating structural steel and tubes demonstrated enhanced energy dissipation capabilities, surpassing other specimens in this critical performance aspect. An in-depth analysis was also conducted by comparing the ductility coefficient and the equivalent viscous damping coefficient to evaluate the joints’ performance in dissipating energy, coupled with a thorough examination of their stiffness deterioration behavior. The conclusion is that the energy dissipation capacity and stiffness degradation of distinctly shaped SRC column joints are superior to those of conventional, distinctly shaped concrete column joints, indicating promising application prospects.
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- 2024
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13. Quantitative three-dimensional imaging of chemical short-range order via machine learning enhanced atom probe tomography
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Yue Li, Ye Wei, Zhangwei Wang, Xiaochun Liu, Timoteo Colnaghi, Liuliu Han, Ziyuan Rao, Xuyang Zhou, Liam Huber, Raynol Dsouza, Yilun Gong, Jörg Neugebauer, Andreas Marek, Markus Rampp, Stefan Bauer, Hongxiang Li, Ian Baker, Leigh T. Stephenson, and Baptiste Gault
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Science - Abstract
Abstract Chemical short-range order (CSRO) refers to atoms of specific elements self-organising within a disordered crystalline matrix to form particular atomic neighbourhoods. CSRO is typically characterized indirectly, using volume-averaged or through projection microscopy techniques that fail to capture the three-dimensional atomistic architectures. Here, we present a machine-learning enhanced approach to break the inherent resolution limits of atom probe tomography enabling three-dimensional imaging of multiple CSROs. We showcase our approach by addressing a long-standing question encountered in body-centred-cubic Fe-Al alloys that see anomalous property changes upon heat treatment. We use it to evidence non-statistical B2-CSRO instead of the generally-expected D03-CSRO. We introduce quantitative correlations among annealing temperature, CSRO, and nano-hardness and electrical resistivity. Our approach is further validated on modified D03-CSRO detected in Fe-Ga. The proposed strategy can be generally employed to investigate short/medium/long-range ordering phenomena in different materials and help design future high-performance materials.
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- 2023
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14. Anisotropy of Additively Manufactured Metallic Materials
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Binghan Huangfu, Yujing Liu, Xiaochun Liu, Xiang Wu, and Haowei Bai
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additive manufacturing ,thermal-affected zone ,anisotropy ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Additive manufacturing (AM) is a technology that builds parts layer by layer. Over the past decade, metal additive manufacturing (AM) technology has developed rapidly to form a complete industry chain. AM metal parts are employed in a multitude of industries, including biomedical, aerospace, automotive, marine, and offshore. The design of components can be improved to a greater extent than is possible with existing manufacturing processes, which can result in a significant enhancement of performance. Studies on the anisotropy of additively manufactured metallic materials have been reported, and they describe the advantages and disadvantages of preparing different metallic materials using additive manufacturing processes; however, there are few in-depth and comprehensive studies that summarize the microstructural and mechanical properties of different types of additively manufactured metallic materials in the same article. This paper begins by outlining the intricate relationship between the additive manufacturing process, microstructure, and metal properties. It then explains the fundamental principles of powder bed fusion (PBF) and directed energy deposition (DED). It goes on to describe the molten pool and heat-affected zone in the additive manufacturing process and analyzes their effects on the microstructure of the formed parts. Subsequently, the mechanical properties and typical microstructures of additively manufactured titanium alloys, stainless steel, magnesium–aluminum alloys, and high-temperature alloys, along with their anisotropy, are summarized and presented. The summary indicates that the factors leading to the anisotropy of the mechanical properties of metallic AM parts are either their unique microstructural features or manufacturing defects. This anisotropy can be improved by post-heat treatment. Finally, the most recent research on the subject of metal AM anisotropy is presented.
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- 2024
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15. Update of patient-reported quality-of-life measurement instruments for patients with atopic dermatitis
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Huihui LU, Yingxia GAO, Qianying ZHANG, Zhenzhen CAO, and Xiaochun LIU
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atopic dermatitis ,patient-reported outcomes ,quality of life ,measurement instrument ,Dermatology ,RL1-803 - Abstract
Atopic dermatitis (AD) is a chronic inflammatory skin disease with the highest disease burden among non-fatal dermatoses. Severe itching and frequent recurrence seriously affect the patients′ psychological and social functions, resulting in a significant decline in the patients′ quality of life. Using effective measurement instrument to assess the quality of life is an effective way to evaluate the quality of life of AD patients, and to improve patients′ care experience and the clinical outcomes. Here, we review the patient-reported quality-of-life measurement instruments, including generic instruments, dermatology-specific instruments, and disease-specific instruments used in AD. The generic instruments can be used to compare the quality of life of patients with AD and non-skin diseases, while the dermatology-specific instruments can be used to compare the quality of life of patients with different skin diseases. Dermatology-specific instruments and disease-specific instruments used in AD may have greater discriminatory power and higher specificity and sensitivity for subtle changes. How to choose the appropriate scale in clinical practice and research depends on the research question and the applicable population.
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- 2023
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16. Study on Fungal Diversity during the Pile-fermentation and Autoclaved Process of Liupao Tea
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Xinhui WU, Jinjie DU, Xiaochun LIU, Kaibin LIAO, Yuna QIN, Weijie LIANG, Ruijin QIU, and Lingzhi ZHANG
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liupao tea ,pile-fermentation ,autoclave ,fungal diversity ,Food processing and manufacture ,TP368-456 - Abstract
The unique sensory quality and health effect of Liupao tea are closely related to the participation of microorganisms in the pile-fermentation process. In order to explore the diversity and distribution of fungi in Liupao tea samples during the pile-fermentation and autoclaved process, traditional isolation and culture method and molecular biological identification technology were used to isolate and identify fungi from 14 samples including the Liupao raw tea, the samples of pile-fermentation process and those of autoclaved process in this study. The results were as follows: 13 genera and 39 species fungi were isolated and identified from the samples. Among them, 23 fungi were reported firstly in Liupao tea, including 3 species of golden flower fungi and 6 species of yeasts. Aspergillus and Penicillium were the dominant fungi genera in Liupao raw tea and the samples of pile-fermentation process. Only Aspergillus niger, Aspergillus sydowii, Penicillium laeve and Penicillium gerundense could be isolated from the samples after autoclaved, and other Aspergillus and Penicillium fungi were almost undetectable. Talaromyces was the dominant genus in the samples of autoclaved process. In terms of species, Aspergillus niger and Arxula adeninivorans were the dominant fungal in all tea samples. The results would enrich the cognition of fungal diversity during the processing of Liupao tea, and provide the material basis and theoretical basis for further exploring the effects of different tea source fungi on the quality of Liupao tea.
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- 2023
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17. Evaluation and Prediction Analysis of 3- and 5-Year Relative Survival Rates of Patients with Cervical Cancer: A Model-Based Period Analysis
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Xiaodong Fan MD, Wei He MD, Qing Zhang MD, Binjie Zhang MD, Li Dong PhD, Li Li MD, and Xiaochun Liu PhD
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Background Cervical cancer remains a threat to female health due to high mortality. Clarification of the long-term trend of survival rate over time and the associated risk factors would be greatly informative to improve the prognosis of cervical cancer patients. Methods This retrospective study was based on data extracted from the Surveillance, Epidemiology, and End Results (SEER) database of the United States. The 3-year and 5-year overall survival rates of patients with cervical cancer during 2002–2006, 2007–2011, and 2012–2016 were analyzed. Period analysis was used to assess the variation in survival rate stratified by age, race, and socioeconomic status during the 15-year study period and then predicted the relative survival rate in the following period from 2017 to 2021. Results During 2002–2016, the 3-year relative survival rate of cervical cancer patients increased from 73.1% to 73.5% with a high jump between 2007 and 2011. This upward trend is expected to continue to 74.3% between 2017 and 2021. Patients older than 60 years, black ethnicity, or medium and high poverty status were likely to have a lower relative survival rate. Conclusion This study confirmed the increased relative survival rate of cervical cancer patients over years and identified relevant risk factors. Targeted initiatives for elderly and socially underprivileged individuals may be able to mitigate inequality.
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- 2024
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18. Dynamic impacts of public health events on price fluctuations in broiler industry Chain in China: Evidence from COVID-19 epidemic.
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Ning Xie, Haixin Fan, Xiaochun Liu, Feng Ye, and Zhenlin Weng
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Medicine ,Science - Abstract
Using weekly data from January 2020 to December 2021 on the prices of various links in the Chinese broiler industry chain and the COVID-19 epidemic, we employed a time-varying parametric vector auto-regressive (TVP-VAR) model to investigate the dynamic effects of public health events on price fluctuations of upstream, midstream, and downstream products in the Chinese broiler industry chain. Our findings showed that the COVID-19 epidemic had different effects on the prices of various broiler products, both in direction and magnitude, at different lags and time intervals. Chicken and live chicken prices were impacted the most, followed by broiler chick prices, while broiler feed prices were impacted the least. The epidemic constantly impacted broiler chick and chicken prices, while its effect on live chicken prices was initially negative but turned positive afterwards. Additionally, the impact of the COVID-19 epidemic on broiler product prices consistently increased with more extended lag periods. The impulse responses at different epidemic time points were heterogeneous. With the results of this study, policy recommendations can be suggested to relevant government departments to optimize the prevention and control measures for public health emergencies and ensure price stability in the broiler industry.
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- 2024
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19. Geophysical Evidence of the Collisional Suture Zone in the Prydz Bay, East Antarctica
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Lei Fu, Jingxue Guo, Weisen Shen, Xin Wang, Xiaochun Liu, Xiaofei Chen, and Xiangyun Hu
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nodal seismic array ,receiver function ,magnetotellurics ,prydz belt ,Larsemann Hills ,Geophysics. Cosmic physics ,QC801-809 - Abstract
Abstract The location and origin of Neoproterozoic‐Cambrian sutures provide keys to understand the formation and evolution of the supercontinent Gondwana. The Larsemann Hills is located near a major Neoproterozoic‐Cambrian suture zone in the Prydz Belt, but has not been examined locally by comprehensive geophysical studies. In this study, we analyzed data collected from a one‐dimensional (1D) joint seismic‐MT array deployed during the 36th Chinese National Antarctic Research Expedition. We found that a sharp Moho discontinuity offset of 6–8 km shows up in the stacked image of teleseismic P‐wave receiver function analysis; coinciding with the abrupt Moho offset, a near‐vertical channel with (a) low resistivity extending to the uppermost mantle depths, and (b) high crustal Poisson's ratio in the crust is identified. These findings provide evidence for the determination of the location and collisional nature of the Prydz belt or a portion of it.
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- 2024
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20. Clinical and molecular epidemiology of carbapenem-resistant Enterobacteriaceae in pediatric inpatients in South China
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Zhile Xiong, Chao Zhang, Kurosh Sarbandi, Zhuwei Liang, Jialiang Mai, Bingshao Liang, Hao Cai, Xiantang Chen, Fei Gao, Fangjun Lan, Xiaochun Liu, Shuyan Liu, and Zhenwen Zhou
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carbapenem-resistant enterobacteriaceae ,antimicrobial drug resistance ,enterobacteriaceae ,children ,multilocus sequence typing ,Microbiology ,QR1-502 - Abstract
ABSTRACT Carbapenem-resistant Enterobacteriaceae (CRE) are a substantial health burden. Existing management guidelines are primarily based on clonal evidence. Therefore, epidemiological data are required. We evaluated the risk factors for CRE colonization and described the molecular and clinical characteristics of CRE colonization in pediatric inpatients in Guangzhou, China. Pediatric inpatients from three hospitals in Guangzhou, China, between July 2019 and January 2021 were included. Fecal samples were collected and screened for CRE. Microbiological cultures were grown on MacConkey agar plates, and bacteria were identified with a mass spectrometry microbial identification system. Antimicrobial susceptibility was tested with a VITEK2 system, and carbapenemase genes were amplified. A case-control study was conducted to evaluate the risk factors for fecal CRE colonization in pediatric inpatients. Of 4,033 patients screened, 158 (3.92%) were positive for CRE, including Escherichia coli (51.27%), Klebsiella pneumoniae (37.97%), and Enterobacter cloacae (6.96%). The most common carbapenemase genes were blaNDM-5 (51.89%), blaNDM-1 (15.19%), and blaIMP-4 (7.60%) and blaKPC-2 (3.80%). Hematological malignancies, respiratory diseases, otolaryngological diseases, nervous system diseases, oral administration of third-generation cephalosporins, and the combined use of two or more antibiotics were independently associated with CRE colonization. The most prevalent carbapenem-resistant K. pneumoniae sequence types (STs) were ST11 (8.06%), ST37 (8.06%), and ST76 (8.06%), and the most prevalent carbapenem-resistant E. coli STs were ST10 (9.88%), ST48 (13.58%), and ST58 (8.64%). Pediatric inpatients were colonized by a diversity of CRE strains. Infection control and prevention measures should be implemented to reduce CRE colonization. IMPORTANCE This study assessed the clinical and molecular epidemiology of carbapenem-resistant Enterobacteriaceae in pediatric inpatients at three hospitals in South China by means of screening stool samples for carbapenem-resistant genes and a nested case-control study to determine risk factors for carriage of carbapenem-resistant Enterobacteriaceae. Of 4,033 fecal samples screened, 158 (3.92%) were positive for CRE, including Escherichia coli (51.27 %), Klebsiella pneumoniae (37.97%), and Enterobacter cloacae (6.96%). The most common carbapenemase genes harbored by gastrointestinal CRE strains were blaNDM-5, blaNDM-1, and blaIMP-4. Hematological malignancies, respiratory diseases, otolaryngological diseases, nervous system diseases, oral administration of third-generation cephalosporins, and the combined use of two or more antibiotics were independently associated with CRE colonization.
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- 2023
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21. Arginine vasopressin injection rescues delayed oviposition in cyp19a1b-/- mutant female zebrafish
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Katherine Shaw, Chunyu Lu, Xiaochun Liu, and Vance L. Trudeau
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aromatase ,brain ,estrogen ,neuropeptide ,hormone ,arginine vasopressin ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
In zebrafish, estrogens produced in the ovaries via Cyp19a1a activity are required for both sexual differentiation of the ovary during early development as well as maintenance of the ovarian state during adulthood. The importance of Cyp19a1b that is highly expressed in the brain for female reproduction is still under study. We previously reported that female cyp19a1b-/- mutant zebrafish have significantly lower brain estradiol levels and impaired spawning behavior characterized by an increased latency to oviposition during dyadic sexual behavior encounters. In the current study, we provide evidence that the delayed oviposition in female cyp19a1b-/- mutants is linked to impaired arginine vasopressin (Avp) signaling. Droplet digital PCR experiments revealed that levels of the estrogen receptors, avp, and oxytocin (oxt) are lower in the hypothalamus of mutant females compared to wildtype fish. We then used acute intraperitoneal injections of Avp and Oxt, along with mixtures of their respective receptor antagonists, to determine that Avp can uniquely rescue the delayed oviposition in female cyp19a1b-/- mutants. Using immunohistochemistry, we demonstrated that Cyp19a1b-expressing radial glial cell (RGC) fibers surround and are in contact with Avp-immunopositive neurons in the preoptic areas of the brain. This could provide the neuroanatomical proximity for RGC-derived estrogens to diffuse to and activate estrogen receptors and regulate avp expression levels. Together these findings identify a positive link between Cyp19a1b and Avp for female zebrafish sexual behavior. They also suggest that the female cyp19a1b-/- mutant behavioral phenotype is likely a consequence of impaired processing of Avp-dependent social cues important for mate identification and assessment.
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- 2023
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22. The anomalous negative electric current sensitivity of a precipitation hardened Al alloy during electrically-assisted forming
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Hongrui Dong, Xiaoqiang Li, Yong Li, Shiteng Zhao, Haibo Wang, Xiaochun Liu, Bao Meng, and Kai Du
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Electrically-assisted forming ,AA7075-T6 ,Precipitate ,Constitutive model ,Mining engineering. Metallurgy ,TN1-997 - Abstract
It has been known for decades that the formability of metal sheets can be improved effectively by electrically-assisted (EA) forming. However, it remains controversial as to the detailed mechanisms and the manifestation of electrical effects can vary in different materials. In this paper, the EA flow behavior and mechanism of a precipitation hardened AA7075-T6 were studied. The term “electric current density sensitivity” (ECDS) was introduced to describe the athermal effect. The results show that Joule heating is the main influence factor, while the athermal effect varies with the electric–thermal parameters. Here, we report an anomalous negative electric current sensitivity in AA7075-T6, i.e. the flow stress increases with current density under the same temperature and strain rate when the temperature is ≤ 150 °C and strain rate is ≥ 0.005/s. The above phenomena are attributed to the local Joule heating and promoted atom diffusion under the action of the current, leading to the dissolution of GPZ, the formation of fine precipitate and Cr segregation-induced vacancies. Further, an extended dislocation density based constitutive model was proposed to cover the ECDS and softening effect, which could predict the flow behavior of 7075-T6 under EA forming, including the negative electric current sensitivity. The above work provides a viable method to simultaneously control both the shape and performance of the metal part. Meanwhile, the corresponding mechanism shed new light into the understanding of electroplasticity.
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- 2023
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23. Risk factors for patients with acute hospital-acquired symptomatic pulmonary thromboembolism
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Lujuan Ye, Hailiang Xie, Minggui Lai, Guofu Zheng, Yuancai Xie, and Xiaochun Liu
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Medicine ,Science - Abstract
Abstract This study aimed to identify independent risk factors for acute hospital-acquired symptomatic pulmonary embolism (HA-SPE) by comparing the clinical data of HA-SPE and acute nonhospital-acquired symptomatic pulmonary embolism (NHA-SPE). A total of 292 patients were included in the analysis and divided into two groups: 191 patients had acute NHA-SPE, and 101 patients had acute HA-SPE. The average age of these 292 patients was 63.2 years, and the sample included 145 males. Multivariate analysis showed that malignant tumour (OR, 3.811; 95% CI [1.914–7.586], P = 0.000), recent surgery (OR, 7.310; 95% CI 3.392–15.755], P = 0.000), previous VTE (OR, 5.973; 95% CI 2.194 16.262], P = 0. 000), and the length of stay (LOS) (OR, 1.075; 95% CI [1.040–1.111], P = 0.000) were independent risk factors for acute HA-AEP. The c-statistic for this model was 0.758 (95% CI [0.698–0.800], P
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- 2023
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24. Acute septic thrombophlebitis of the lower extremities due to foreign body injury and infection: a case report
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Guofu Zheng, Daoxiong Xiao, Hailiang Xie, Minggui Lai, Bo Ye, and Xiaochun Liu
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Foreign body ,Scrub typhus ,Septic thrombophlebitis ,Injury ,Case report ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Septic thrombophlebitis (STP) of the lower extremities caused by foreign bodies is rare in the clinic, and the symptoms are serious. If the correct treatment is not implemented as soon as possible, the patient may progress to sepsis. Case presentation We report the case of a 51-year-old normally healthy male who developed fever 3 days after field work. When he was weeding with a lawn mower in the field, a metal foreign body from the grass flew into his left lower abdomen, resulting in an eschar on his left lower abdomen. He was diagnosed with scrub typhus but did not respond well to anti-infective treatment. After a detailed inquiry of his medical history and an auxiliary examination, the diagnosis was confirmed as STP of the left lower limb caused by a foreign body. After surgery, anticoagulation and anti-infection treatment, the infection and thrombosis were controlled, and the patient was cured and discharged. Conclusions STP caused by foreign bodies is rare. Early detection of the aetiology of sepsis and early adoption of the correct measures can effectively block the progression of the disease and reduce the patient’s pain. Clinicians should identify the source of sepsis through a medical history and clinical examination.
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- 2023
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25. Effects of stellate ganglion block on perimenopausal hot flashes: a randomized controlled trial
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Ying Li, Jia Chang, Gaoxiang Shi, Wenjing Zhang, Hui Wang, Lingyun Wei, Xiaochun Liu, and Weiwei Zhang
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stellate ganglion block ,perimenopause ,hot flashes ,sleep quality ,Kupperman Index and Pittsburgh Sleep Quality Index ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
BackgroundHot flashes are common symptoms afflicting perimenopausal women. A stellate ganglion block (SGB) is believed to be an effective treatment for hot flashes; however, more evidence is needed to evaluate its safety and efficacy in relieving perimenopausal hot flashes.ObjectiveTo investigate the efficacy and safety of SGB for the treatment of perimenopausal hot flashes.MethodsA randomized controlled trial was conducted at Shanxi Bethune Hospital. Forty perimenopausal women with hot flashes were recruited from April 2022 to November 2022 and randomly assigned to receive either 6 consecutive SGB treatments or 6 consecutive saline placebo treatments. The primary outcome was the change in hot flash symptom score from baseline to 12 weeks after treatment. The secondary outcomes were the change in hot flash symptom score from baseline to 12 weeks after treatment and the post-treatment Kupperman Index (KI) and Pittsburgh Sleep Quality Index (PSQI) scores.ResultsOf the 40 randomized subjects, 35 completed the study. All the variables were significantly improved. During 12 weeks of follow-up, the hot flash scores, Kupperman Menopause Scale scores, and Pittsburgh Sleep Quality Scale scores decreased significantly. Two subjects in the SGB treatment group experienced transient hoarseness, and the incidence of related adverse events was 10%. No related adverse events occurred in the control group.ConclusionCompared to the control treatment, SGB treatment was a safe and effective nonhormone replacement therapy that significantly relieved perimenopausal hot flashes and effectively improved sleep quality. Additional studies are needed to assess the long-term efficacy of this therapy.
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- 2023
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26. Potential molecular targets for intervention in pelvic organ prolapse
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Xia Wu, Xiaochun Liu, and Tingting Li
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potential biomarkers ,intervention ,pelvic organ prolapse ,micro-mechanism ,molecular targets ,Medicine (General) ,R5-920 - Abstract
Pelvic organ prolapse (POP) is a concerning gynecological benign illness in middle-aged and senior women. Its etiology is complex, the incidence rate is high, symptoms are clinically subjective, and its influence tends to be polarized. At present, for those who need medical treatment, whether surgical or non-surgical, complications cannot be ignored, and treatment effect needs to be optimized. However, there is a lack of accurate molecular biological interventions for the prevention, diagnosis, progression delay, and treatment of POP. Here, we reviewed the current state of understanding of the molecular mechanisms and factors associated with POP etiology. These factors include cyclins, matrix metal peptidases/tissue inhibitors of metalloproteinases, microRNAs, homeobox A11, transforming growth factor β1, insulin-like growth factor 1, fibulin 5, lysyl oxidase-like 1, oxidative stress, inflammatory response, estrogen, and other potential biomarkers associated with POP. In addition, relevant molecular targets that may be used to intervene in POP are summarized. The aim of this review was to provide more information to identify accurate potential biomarkers and/or molecular targets for the prevention, diagnosis, progression delay, and treatment of POP, with the goal of improving medical treatment for patients at-risk for POP or having POP. Continued research is needed to identify additional details of currently accepted molecular mechanisms and to identify additional mechanisms that contribute to POP.
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- 2023
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27. Manipulating the ordered oxygen complexes to achieve high strength and ductility in medium-entropy alloys
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Meiyuan Jiao, Zhifeng Lei, Yuan Wu, Jinlong Du, Xiao-Ye Zhou, Wenyue Li, Xiaoyuan Yuan, Xiaochun Liu, Xiangyu Zhu, Shudao Wang, Huihui Zhu, Peipei Cao, Xiongjun Liu, Xiaobin Zhang, Hui Wang, Suihe Jiang, and Zhaoping Lu
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Science - Abstract
Ordered oxygen complexes (OOCs) endow a unique interstitial strengthening mechanism for simultaneously enhancing strength and ductility in HEAs. Here, the authors demonstrate whether such mechanism can be extended to other alloy systems and how the formation of OOCs is tailored.
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- 2023
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28. Assessing potassium levels in critically ill patients with heart failure: application of a group‐based trajectory model
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Zehao Lin, Jiawei Zheng, Xiaochun Liu, Xiaojun Hu, Ren Fuxian, and Dengfeng Gao
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Blood potassium trajectory ,Heart failure ,Group‐based trajectory model ,Prognosis ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Aims Abnormalities in potassium homeostasis are frequently seen in hospitalized patients. A poor outcome in heart failure (HF) has been linked to both hypokalaemia and hyperkalaemia. The studies on the connection between variations in potassium levels and all‐cause mortality remain scarce. We delineated trajectories of potassium levels and investigated the association of these trajectories with all‐cause mortality of critically ill patients with HF. Methods and results A retrospective analysis of blood potassium levels (9 times) in patients with HF after being admitted to the intensive care unit (ICU). Potassium levels were divided into three groups according to the first serum potassium level in ICU and thereafter categorized as follows: hypokalaemia group (n = 336) (5.0 mmol/L). According to the group‐based trajectory modelling (GBTM), the hyperkalaemia group and the normal blood potassium‐level group can be divided into three trajectory groups: the low‐level stable group, the medium‐level stable group, and the high‐level decline group. The hypokalaemia group can be divided into two trajectory groups: the low‐level rise group and the high‐level rise group. A total of 4053 HF patients were included (mean age 71.81 ± 13.12 years, 54.90% males, 45.10% females). After adjusting for possible confounding variables, in the hyperkalaemia group, the low‐level stable group had lower 28 day [high‐level decline group vs. low‐level stable group hazard ratio (HR), 95% confidence interval (CI): 2.917, 1.555–5.473; P
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- 2023
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29. Screening of hepatitis D virus in blood donors in Dalian
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Dan LIU, Dan WANG, Xiaochun LIU, Chunxiang LI, Liang ZANG, and Xuelian DENG
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blood donor ,hepatitis d virus ,screening of hdv antibody ,Diseases of the blood and blood-forming organs ,RC633-647.5 ,Medicine - Abstract
Objective To investigate the prevalence of hepatitis D virus in Dalian blood donors. Methods The samples reactive to HBV in blood screening were selected with the following confirmed results: 1)HBsAg+ &HBV DNA+ ; 2)HBsAg+ & HBV DNA-; 3)HBsAg-&HBV DNA+ ; 4)NAT-yield uncertain. Qualified samples in routine blood screening were additionally tested with anti-HBc+ and anti-HBs+. All samples selected were tested HDV IgG further. Initial reactive samples would be tested by another HDV IgG assay and HDV IgM assay. HDV IgG positive was confirmed when samples were reactive to two HDV IgG assays. Results None HDV antibodies were detected among 1 344 unqualified samples (507 HBsAg+ &HBV DNA+, 33 HBsAg+ &HBV DNA-, 477 HBsAg-&HBV DNA+ and 327 NAT-yield uncertain samples) or 766 qualified samples (397 anti-HBc+ and 369 anti-HBs samples) in blood screening. Conclusion The prevalence of HDV infections among Dalian blood donors eligible in pre-donation screening seemed extremely low. However, for areas with high HBV prevalence, the risk of blood safety caused by OBI co-infection with HDV should not be ignored.
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- 2023
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30. Tectonic-magmatic setting for Early Cretaceous low-sulfidation epithermal gold deposits in the Xing–Meng Orogenic Belt: Constraints from zircon U–Pb and Hf isotopic data of wulaga deposit, NE China
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Yongbin Wang, Xiaochun Liu, Yunkang Guo, Jiaqi Cai, and Qing-dong Zeng
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Zircon U–Pb age ,Sr–Nd–Pb–Hf isotopic Composition ,Epithermal gold deposit ,Wulaga gold deposit ,Xing–meng orogenic belt ,Geology ,QE1-996.5 - Abstract
The Xing–Meng Orogenic Belt hosts an amount of low-sulfidation epithermal gold deposits. However, the tectonic-magmatic setting remains problematic, which hinders understanding the factors that control the gold endowment in the region. Wulaga deposit is the largest low-sulfidation epithermal gold deposit in the northeastern Xing–Meng Orogenic Belt. Gold mineralization occurs in the crypto-explosive breccia zone of subvolcanic granodiorite porphyry. Zircon U–Pb ages of three granodiorite apophyses and previous pyrite Rb–Sr dating (113.8 ± 4.4 Ma) indicate granodiorite porphyry and gold mineralization was coeval. The ore-related granodiorite porphyry is moderate SiO2, high-K calc-alkaline, and metaluminous, suggesting an I-type granite. Moreover, Wulaga granodiorite porphyry displays low initial 87Sr/86Sr ratios and positive εNd(t) values with TDM2(Nd) of 799.7–897.4 Ma and εHf(t) values with TDM2(Hf) of 652–785 Ma, indicating that it was derived from partial melting of the Neoproterozoic juvenile mafic lower crust. Ti-in-zircon thermometry, medium–high Sr/Y ratio, high Ba/La, and fO2 value indicate that Wulaga granodiorite porphyry formed at relatively low temperatures (∼700 °C), rich water, and high fugacity within the stability field of garnet in the juvenile lower crust. Combined with ore-related tectonic-magmatic activities in the Wulaga, Dong'an, and Sandaowanzi gold deposits, the Early Cretaceous low-sulfidation epithermal gold deposits in the Xing–Meng Orogenic Belt were formed from magmatic-hydrothermal events triggered by mutual interaction between post-orogenic lithospheric extension related to the closure of the Mongol-Okhotsk Ocean and arc-back extension associated with rollback of the Paleo-Pacific Ocean plate. These data indicate the potential existence of the Early Cretaceous epithermal gold deposits that are related to the contemporaneous igneous activity.
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- 2022
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31. Molecular epidemiology of HIV-1 among blood donors in Dalian: 2011~2020
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Xiaohan GUO, Xiaochun LIU, Yingying WANG, Liang ZANG, Daniel Candotti, and Xuelian DENG
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hiv-1 ,gene subtype ,blood donor ,molecular epidemiology ,Diseases of the blood and blood-forming organs ,RC633-647.5 ,Medicine - Abstract
Objective To investigate HIV-1 subtype distribution and trend among Dalian blood donors between 2011 and 2020, in order to provide information to improve blood safety and HIV prevention. Methods HIV RNA was purified from plasma samples of Dalian blood donors with confirmed HIV infection, which were collected between 2011 and 2020. The HIV pol gene was amplified and sequenced. HIV-1 subtypes were determined by phylogenetic analysis. Results HIV RNA was successfully genotyped in 174 samples from HIV-infected donors. The main subtypes among Dalian blood donors were CRF01_AE(69.5%), CRF07_BC(17.2%), B(5.2%), CRF02_AG(2.9%), C(1.1%), CRF55_01B(1.1%), CRF08_BC(0.6%), CRF59_01B(0.6%) and CRF79_0107(0.6%). There were still 2 cases (1.1%) unclassified. Significant difference was observed when comparing with the published national data. The prevalence of CRF01_AE strains decreased over the years, while CRF07_BC increased significantly. CRF02_AG carriers differed from donors infected with other HIV subtypes by being mostly females (40.0% vs. 2.4%), aged (median: 35y vs. 26y) and lower educational background(junior school degree or below). And 96.7% of local CRF01_AE cases were related to HIV strains, which were reported to circulate in Northeast China and in the MSM population. Conclusion HIV-1 among Dalian blood donors had unique molecular epidemiology and the trends of 07_BC increasing and 01_AE decreasing lagged behind the overall national data. Donor education on blood safety and consultation services to high risk group before donation still need improvement.
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- 2022
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32. Serological and molecular characterization of HBV infection with HBsAg reactive and HBV DNA non-reactive
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Chunxiang LI, Xiaohan GUO, Peng SUN, Xiaochun LIU, Dan LIU, Lei ZHOU, Liang ZANG, Daniel Candotti, and Xuelian DENG
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blood screening ,hbsag positive ,nucleic acid testing ,hbv infection ,mechanisms ,Diseases of the blood and blood-forming organs ,RC633-647.5 ,Medicine - Abstract
Objective To investigate the serological and molecular characteristics of HBsAg+ /HBV DNA non-reactive (NR) infections. Methods Samples tested as HBsAg+ and HBV DNA NR were confirmed by individual NAT repeat testing, viral particle concentration by PEG precipitation combined with in-house nested PCR and real-time quantitative PCR, anti-HBc testing, and HBsAg quantification. HBV sequences were compared with those from donors with chronic and occult infection as controls. Results A total of 792 195 samples were screened between January 2011 and December 2020, of which 53 (1: 14 947) were confirmed HBsAg+ /HBV DNA NR. HBV DNA was detected further in five (9.4%) samples; three S sequences and four Pre Core/Core sequences were obtained. Unique amino acid substitutions (P130T, P135Q/S, R151Q, G153S and S155F) were found in the Core protein that may affect virus packaging and replication. Conclusion Extremely low HBV DNA level was detected in plasmas of HBsAg+ /HBV DNA NR donors. Barely detectable HBV DNA might be associated with unusual mutations in the Pre Core/Core protein affecting viral replication. More sensitive HBV DNA and/or HBsAg assays may be considered to further reduce the potential HBV transfusion-transmission residual risk.
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- 2022
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33. Experimental study on the fatigue and freeze-thaw properties of geotextile isolation layer in CRTS III ballastless tracks
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Xiaochun Liu, Xian Yang, Weiqi Zheng, Shaohui Xie, Zhihui Zhu, and Zhiwu Yu
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CRTS III ballastless track ,Geotextile isolation layer ,Fatigue performance ,Freeze-thaw cycle ,Mechanical properties ,Experimental research ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
To investigate the fatigue and freeze-thaw properties of the geotextile isolation layer in CRTS III ballastless track, a new type of disc multi-point load distribution device was manufactured. The experimental study was carried out on the geotextile isolation layer subjected to the fatigue load and freeze-thaw cycles. The results showed that the mechanical properties of the geotextile isolation layers were affected by the harsh environment and cyclic load. With the increase of fatigue loading cycles, the dynamic stiffness of the geotextile isolation layers increased and tended to be stable, and the nonlinear performance of the geotextile isolation layer gradually weakened. The freeze-thaw cycle greatly influenced the dynamic stiffness of the geotextile isolation layer compared with the fatigue loadings, and the freeze-thaw cycle action could accelerate the elastic loss of the geotextile isolation layer. Under the fatigue load and freeze-thaw cycles, the tensile strength of the geotextile isolation layer decreased and caused damage to the geotextile isolation layers, which should be paid attention to in long-term service.
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- 2023
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34. Mutation of brain aromatase disrupts spawning behavior and reproductive health in female zebrafish
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Katherine Shaw, Mylène Therrien, Chunyu Lu, Xiaochun Liu, and Vance L. Trudeau
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aromatase ,brain ,cyp19a1b ,estrogen ,hormone ,neuroendocrine ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
Aromatase (Cyp19a1) is the steroidogenic enzyme that converts androgens into bioactive estrogens, and hence is in a pivotal position to mediate reproduction and sexual behavior. In teleosts, there are two aromatase paralogs: cyp19a1a that is highly expressed in granulosa and Leydig cells in the gonads with critical function in sexual differentiation of the ovary, and cyp19a1b that is highly expressed in radial glial cells in the brain with unknown roles in reproduction. Cyp19a1-/- mutant zebrafish lines were used to investigate the importance of the cyp19a1 paralogs for spawning behavior and offspring survival and early development. Mutation of cyp19a1b was found to increase the latency to the first oviposition in females. Mutation of cyp19a1b in females also increased the number of eggs spawned; however, significantly more progeny died during early development resulting in no net increase in female fecundity. This finding suggests a higher metabolic cost of reproduction in cyp19a1b-/- mutant females. In males, the combined mutation of both cyp19a1 paralogs resulted in significantly lower progeny survival rates, indicating a critical function of cyp19a1 during early larval development. These data establish the specific importance of cyp19a1b for female spawning behavior and the importance of the cyp19a1 paralogs for early larval survival.
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- 2023
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35. Transcriptome profiling of the gonad during sex differentiation in hermaphroditic brown-marbled grouper (Epinephelus fuscoguttatus)
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Xi Wu, Yang Yang, Tong Wang, Chaoyue Zhong, Yuhao Tao, Leyi Chang, Zining Meng, and Xiaochun Liu
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Transcriptome ,Sex differentiation ,Gonad ,Meiosis ,Brown-marbled grouper ,Aquaculture. Fisheries. Angling ,SH1-691 - Abstract
Sex differentiation is an intricate process regulated by a complicatedly organized network especially in hermaphroditic fish. The brown-marbled grouper (Epinephelus fuscoguttatus) is a protogynous hermaphroditic fish, however, the regulatory mechanism of its sex differentiation is still unclear. In present study, transcriptome sequencing of the gonads at 117 dph and 259 dph was performed to explore the molecular mechanism underlying sex differentiation. A total of 37,434,906,973 clean reads were generated from six cDNA libraries. QPCR results of 12 genes related to sex differentiation indicated the reliability of transcriptome data. RNA-seq data showed that the genes in retinoic acid signal pathway participate in the early stage of sex differentiation. When the oocyte was observed in histology, the germ cell had finished the preparation of first meiosis with high expression of many meiosis-related genes, including sycp1, sycp3, mlh3, crem, spo11, msh5, and rec8. The germ cells in 259 dph gonad were classified into six stages by their histological morphology. Besides, male-related genes, gsdf, sox9, dmrt1, and dmrt3, might play roles in sex differentiation. Our study, for the first time, investigated the transcriptome from brown-marbled grouper, and identified functional genes, GO terms, and KEGG pathways involved in sex differentiation. These data will contribute to future studies on the molecular mechanism of sex differentiation in teleost.
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- 2023
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36. A tough and mechanically stable adhesive hydrogel for non-invasive wound repair
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Xiaochun Liu, Si Qin, Lei Xu, Guo Fu, Yongjun Huang, Chaoqun Yu, Guoyun Cheng, Ying Li, Yunzhi He, Yong Qi, and Dawei Sun
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adhesive hydrogel ,topological adhesion ,wound repair ,toughness ,mechanical stability ,Biotechnology ,TP248.13-248.65 - Abstract
Wound healing has been a great challenge throughout human history. Improper treatment for wounds is so easy to lead to infection and a series of serious symptoms, even death. Because of the ability of absorbing fluid and keeping a moist environment, the hydrogel with 3D networks is ideal candidate for wound dressing. More important, it has good biocompatibility. However, most of the hydrogel dressings reported have weak mechanical properties and adhesion properties, which greatly limit their clinical application. Herein, a tough adhesive hydrogel with good mechanical stability for non-invasive wound repair is reported. The hydrogel is composed of polyethylene glycol dimethacrylate (PEGDA), chitosan (CS) and chitin nano-whisker (CW). PEGDA and CS form interpenetrating network hydrogel through free radical polymerization reaction under the UV light. The introduction of CW further enhances the toughness of the hydrogel. The pH-sensitive CS can form adhesion to various materials through topological adhesion. As a wound closure repair material, PEGDA/CS/CW hydrogel not only has the characteristic of effectively closing the wound, defending against invading bacteria, and keeping the wound clean, but also has good tensile and mechanical stability, which is expected to realize the closure and repair of joints and other moving parts of the wound. This adhesive hydrogel is proven a promising material for wound closure repair.
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- 2023
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37. Quality Component Analysis and Antioxidant Function of Theabrownins from Liupao Tea during Fermentation Process
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Jinjie DU, Xinhui WU, Yuqing DAI, Xiaochun LIU, Kaibing LIAO, Yuna QIN, Lihua ZHONG, and Lingzhi ZHANG
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liupao tea ,sensory quality ,chemical component ,theabrownins ,antioxidant activity ,Food processing and manufacture ,TP368-456 - Abstract
This study investigated the changes of the sensory qualities of appearance, color, aroma, taste, leaf bottom and the chemical components of tea polyphenols, free amino acids, soluble sugar, caffeine, flavonoids, theabrownin (TB), theaflavin (TF) and thearubigin (TR) using the Liupao tea during processing and was produced by group species Zhongcha Tea Factory in Cangwu County, Wuzhou City, Guangxi, China. In addition, the chemical composition, and the antioxidant of the theabrownin (TB) that extracted from the Liupao tea were investigated. The results showed that the contents of water extract, tea polyphenols, thearubigin (TR), free amino acids and flavonoids were significantly decreased during the fermentation process (P40 d>60 d>20 d. The results of this study would provide a theoretical basis for the production and processing of Liupao tea.
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- 2022
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38. Exogenous Xyloglucan Oligosaccharides Alleviate Cadmium Toxicity in Boehmeria nivea by Increasing the Cadmium Fixation Capacity of Cell Walls
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Yushen Ma, Hongdong Jie, Long Zhao, Ying Zhang, Pengliang He, Xueying Lv, Xiaochun Liu, Yan Xu, and Yucheng Jie
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xyloglucan oligosaccharides ,ramie ,subcellular distribution ,hemicellulose ,cell wall ,cadmium ,Agriculture - Abstract
Xyloglucan is an important component of hemicellulose, and xyloglucan oligosaccharides (Xh), which are metabolized by xyloglucan, play an important role in plant growth and development. However, the regulatory effects of the external application of Xh under cadmium (Cd) stress have not been determined. In this study, we evaluated the mechanism by which Xh contributes to resistance to Cd stress in ramie, a candidate plant species for toxic ion removal. The external application of Xh effectively attenuated the effects of Cd on ramie growth and photosynthetic pigments. Cd stress can also inhibit the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX), resulting in a significant increase in the extent of membrane lipid peroxidation. After the external application of Xh, antioxidant enzyme activity was up-regulated, and damage to membranes in plants was reduced. In addition, the external application of Xh increased Cd retention in roots, thereby significantly decreasing Cd content in shoots. The external application of Xh also regulated the subcellular distribution of Cd and increased the Cd content of the cell wall. In particular, a root cell wall analysis revealed that Cd+Xh treatment significantly increased the hemicellulose content in the cell wall and the amount of Cd retained. In summary, the external application of Xh alleviates Cd toxicity in ramie by increasing the hemicellulose content and the Cd fixation ability of the cell wall and by reducing membrane lipid peroxidation via antioxidant enzymes.
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- 2023
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39. Time-Varying Transformation-Based Adaptive Tracking Control of Uncertain Robotic Systems With Event-Triggered Mechanism
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Lei Zhang, Dan Li, Xiaochun Liu, Hailong Liu, and Yongcheng Zhou
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Accelerated adaptive control ,event-triggering mechanism ,robotic systems ,error transformation ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
In this paper, an adaptive global event-triggered control scheme for uncertain robotic systems, capable of guaranteeing adjustable tracking performance, is developed. Compared with most of the existing results, the proposed control exhibits some features. Firstly, to improve the transient tracking performance without the requirement of large control effort, a time-varying scaling diagonal matrix and an error transformation are constructed so that each element of the tracking error has its own convergence rate, which can be adjusted by selecting the design parameters. Secondly, due to the consideration of decreasing the consumption of network resources, some additional diagonal matrices embedded in the new closed-loop system make the new control gain matrix not symmetric and positive definite, then the stability analysis becomes rather more challenging. To solve this issue, an alternative Lyapunov function is constructed to circumvent the above obstacles. The effectiveness of the proposed approach is verified by a 2-DOF robotic manipulator.
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- 2022
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40. A novel shark single-domain antibody targeting OGT as a tool for detection and intracellular localization
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Xiaozhi Xi, Guokai Xiao, Guiqi An, Lin Liu, Xiaochun Liu, Peiyu Hao, Jennifer Yiyang Wang, Dandan Song, Wengong Yu, and Yuchao Gu
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O-GlcNAc ,OGT ,Shark VNAR ,ELISA ,immunofluorescence ,computer simulation ,Immunologic diseases. Allergy ,RC581-607 - Abstract
IntroductionO-GlcNAcylation is a type of reversible post-translational modification on Ser/Thr residues of intracellular proteins in eukaryotic cells, which is generated by the sole O-GlcNAc transferase (OGT) and removed by O-GlcNAcase (OGA). Thousands of proteins, that are involved in various physiological and pathological processes, have been found to be O-GlcNAcylated. However, due to the lack of favorable tools, studies of the O-GlcNAcylation and OGT were impeded. Immunoglobulin new antigen receptor (IgNAR) derived from shark is attractive to research tools, diagnosis and therapeutics. The variable domain of IgNARs (VNARs) have several advantages, such as small size, good stability, low-cost manufacture, and peculiar paratope structure.MethodsWe obtained shark single domain antibodies targeting OGT by shark immunization, phage display library construction and panning. ELISA and BIACORE were used to assess the affinity of the antibodies to the antigen and three shark single-domain antibodies with high affinity were successfully screened. The three antibodies were assessed for intracellular function by flow cytometry and immunofluorescence co-localization.ResultsIn this study, three anti-OGT VNARs (2D9, 3F7 and 4G2) were obtained by phage display panning. The affinity values were measured using surface plasmon resonance (SPR) that 2D9, 3F7 and 4G2 bound to OGT with KD values of 35.5 nM, 53.4 nM and 89.7 nM, respectively. Then, the VNARs were biotinylated and used for the detection and localization of OGT by ELISA, flow cytometry and immunofluorescence. 2D9, 3F7 and 4G2 were exhibited the EC50 values of 102.1 nM, 40.75 nM and 120.7 nM respectively. VNAR 3F7 was predicted to bind the amino acid residues of Ser375, Phe377, Cys379 and Tyr 380 on OGT.DiscussionOur results show that shark single-domain antibodies targeting OGT can be used for in vitro detection and intracellular co-localization of OGT, providing a powerful tool for the study of OGT and O-GlcNAcylation.
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- 2023
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41. Mesenchymal stem cell-based therapy for female stress urinary incontinence
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Xiaochun Liu, Tingting Li, Jia Zhang, Xiling Lin, Wenzhen Wang, Xiaodong Fan, and Lili Wang
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mesenchymal stem cells ,stress urinary incontinence ,stem cell-based therapy ,animal model ,mechanisms of action ,Biology (General) ,QH301-705.5 - Abstract
Stress urinary incontinence (SUI) adversely affects the quality of life of patients, while the currently available surgical and non-surgical therapies are not effective in all patients. Application of mesenchymal stem cells (MSCs) for regaining the ability to control urination has attracted interest. Herein, we reviewed the literature and analyzed recent studies on MSC-based therapies for SUI, summarized recent treatment strategies and their underlying mechanisms of action, while assessing their safety, effectiveness, and prospects. In addition, we traced and sorted the root literature and, from an experimental design perspective, divided the obtained results into four categories namely single MSC type therapy for SUI, MSC-based combination therapy for SUI, treatment of SUI with the MSC secretome, and other factors influencing MSC therapy. Although evidence demonstrates that the treatment strategies are safe and effective, the underlying mechanisms of action remain nebulous, hence more clinical trials are warranted. Therefore, future studies should focus on designing clinical trials of MSC-based therapies to determine the indications for treatment, cell dosage, appropriate surgical strategies, and optimal cell sources, and develop clinically relevant animal models to elucidate the molecular mechanisms underlying stem cell therapies improvement of SUI.
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- 2023
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42. Quantifying chemical fluctuations around medium-range orders and its impact on dislocation interactions in equiatomic CrCoNi medium entropy alloy
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Guogao Tang, Zilin Zhang, Yujing Liu, Yiyao Wang, Xiang Wu, and Xiaochun Liu
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Chemical fluctuations ,Medium-range orders ,Dislocations ,CrCoNi medium entropy alloy ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Equiatomic multi-principal element alloys manifest unique mechanical properties derived from the single-phase solid solutions with compositional disorders. Recently discovered medium-range orders (MROs) with a size of 1–5 nm in CrCoNi medium entropy alloy acclaimed measurable impact on mechanical properties, which, however has been questioned by density functional theory calculations. Here we report that the formation of MROs is accompanied by the redistribution of constituent elements, and the subtle chemical composition fluctuations could by directly probed and quantified by using a state-of-the-art aberration-corrected transmission electron microscope. The presence of such MROs contributes to an appreciable increase in yield strength (∼40 MPa) with a higher work hardening rate, originating from the strong dislocation interactions with MROs at the incipient plastic deformation. These findings demonstrate that MROs have a significant impact on reducing the mean free path of full/partial dislocations along a specific slipping plane, offering a new avenue for strengthening of equiatomic element alloys by tuning local composition and atomic configurations.
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- 2023
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43. Low-latency time-of-flight non-line-of-sight imaging at 5 frames per second
- Author
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Ji Hyun Nam, Eric Brandt, Sebastian Bauer, Xiaochun Liu, Marco Renna, Alberto Tosi, Eftychios Sifakis, and Andreas Velten
- Subjects
Science - Abstract
Non-line-of-sight imaging can recover the 3D geometry of hidden objects, but is limited by weak multibounce signals. Here, the authors introduce a multipixel time-of-flight NLOS imaging approach, combining array detectors and a fast algorithm, for live reconstruction of natural nonretroreflective objects.
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- 2021
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44. Influence of multi-dimensional environmental knowledge on residents' waste sorting intention: Moderating effect of environmental concern
- Author
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Zhihua He, Yong Liu, Xiaochun Liu, Feng Wang, and Huijia Zhu
- Subjects
waste sorting intention ,system knowledge ,action-related knowledge ,effectiveness knowledge ,environmental concern ,Psychology ,BF1-990 - Abstract
With the rapid increase in household waste, environmental degradation becomes more serious. It is imperative to promote waste sorting in China. This study proposes an extended KAB model to explore the impact mechanism of different dimensions of subjective environmental knowledge on urban residents' waste sorting intention. The study also explores the moderating role of environmental concern in the relationship between three types of subjective environmental knowledge and attitude toward waste sorting. Based on 308 valid questionnaires, through structural equation model, multiple regression analysis, and simple slope test, we found that system knowledge, action-related knowledge, and effectiveness knowledge all have positive impacts on residents' attitudes toward waste sorting, and effectiveness knowledge has the most significant impact. Meanwhile, environmental concern positively moderates the relationship between system knowledge, effectiveness knowledge, and attitude toward waste sorting. This study makes an important theoretical contribution to enrich the existing literature on residents' waste sorting behavior and provides theoretical insights for governmental waste sorting policy formulation at the practical level.
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- 2022
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45. Pancreatic injury following immune checkpoint inhibitors: A systematic review and meta-analysis
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Tian Zhang, Yi Wang, Chunhui Shi, Xiaochun Liu, Shangbin Lv, Xin Wang, and Weihong Li
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immune checkpoint inhibitors ,immune-related adverse events ,meta-analysis ,pancreatic injury ,pancreatitis ,amylase ,Therapeutics. Pharmacology ,RM1-950 - Abstract
Background: Pancreatic injury (pancreatitis, amylase/lipase elevation) is a rare adverse event of immune checkpoint inhibitors (ICIs). With the high number of clinical studies on ICIs, the incidence and characteristics of associated pancreatic injury (PI) need to be reevaluated.Methods: A systematic review and meta-analysis was conducted to assess the incidence of PI in cancer patients who received ICIs in randomized controlled trials (RCTs). PubMed, Embase, the ASCO, ESMO, and AACR conference proceedings before 1 April 2022, were investigated for relevant research.Results: 50 RCTs involving 35,223 patients were included. The incidence of ICIs-PI was 2.22% (95% CI = 1.94%–2.53%). The incidence of PI was 3.76% (95% CI = 1.84–7.67%) when combining two ICIs, which was higher than single ICIs [2.25% (95% CI = 1.91–2.65%)]. The ICIs were ranked from high to low based on PI incidence: PD-L1 inhibitors 3.01% (95% CI = 1.86–4.87%), CTLA-4 inhibitors 2.92% (95% CI = 0.99–8.65%) and PD-1 Inhibitor 2% (95% CI = 1.67–2.39%). The ICI with the highest rate of PI was pembrolizumab 7.23.% (95% CI = 1.69–30.89%). In addition, the incidence of severe ICIs-PI was 2.08% (95% CI = 1.76–2.46%); and the incidence of severe PI was 2.32% (95% CI = 1.76–3.06%) when combining two ICIs, which was higher than single ICI [1.95% (95% CI = 1.58–2.41%)]. The ICIs were ranked from high to low according to the incidence of severe PI: PD-L1 inhibitors 3.1% (95% CI = 1.7–5.64%), CTLA-4 inhibitors 2.69% (95% CI = 0.76–9.49%), PD-1 inhibitors 1.80% (95% CI = 1.41–2.29%).Conclusion: Treatment with multiple ICIs result in a higher incidence of PI compared to single ICIs, irrespective of the grade of pancreatic injury. The incidence of PI caused by PD-L1 inhibitors is higher than that of CTLA-4 inhibitors and PD-1 Inhibitor, and Pembrolizumab has the highest rate of ICIs-PI. Although the incidence of ICIs-PI is not high, they are usually severe (≥ grade 3 events).
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- 2022
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46. Assembly of Genome and Resequencing Provide Insights into Genetic Differentiation between Parents of Hulong Hybrid Grouper (Epinephelus fuscoguttatus ♀ × E. lanceolatus ♂)
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Yang Yang, Leilei Zeng, Tong Wang, Lina Wu, Xi Wu, Junhong Xia, Zining Meng, and Xiaochun Liu
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grouper ,genome ,SNP ,structural variation ,growth traits ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
The Hulong hybrid grouper was bred from the brown-marbled grouper (Epinephelus fuscoguttatus) ♀ and the giant grouper (E. lanceolatus) ♂, combining the advantageous traits of both parents. Possessing an excellent performance, this hybrid’s cultivation promotes the development of the grouper industry. Its male parent, the giant grouper, possesses the fastest growth and the largest body size among all coral-reef-dwelling fish. This species is not only an economically important species in marine aquaculture, but it is also an ideal male parent in the interspecific crossing of grouper species. In the present study, a high-quality chromosome-level genome of the giant grouper was constructed with a total length of 1.06 Gb, consisting of 24 chromosomes and 69 scaffolds. To analyze the genetic differences between the parents of the Hulong hybrid grouper, the structural variations (SVs) between both parental genomes were detected, and a total of 46,643 SVs were obtained. High-quality SNPs were identified from resequencing data. There were significant differences between the two genomes, and the average FST reached 0.685. A total of 234 highly differentiated regions were detected with an FST > 0.9. The protein-coding genes involved in SVs and highly differentiated regions were significantly enriched in metabolic pathways, including fatty metabolism, carbohydrate metabolism, amino acid metabolism and the TCA cycle. These genes may be related to the differences in feeding preferences and the ability to digest carbohydrates between the two grouper species under natural conditions. In addition, protein-coding genes related to the cell cycle and p53-signaling pathway were also detected. These genes may play important roles in the regulation of body size and growth performance. This research provides genomic resources for further breeding works and evolutionary analyses.
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- 2023
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47. Transcriptome Analysis Reveals Differences in Gene Expression in the Muscle of the Brown-Marbled Grouper (Epinephelus fuscoguttatus) with Different Growth Rates
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Tong Wang, Yang Yang, Shirui Gong, Xi Wu, Leilei Zeng, Yuhao Tao, Chaoyue Zhong, Leling Song, and Xiaochun Liu
- Subjects
brown-marbled grouper ,muscle ,growth ,RNA-seq ,Biology (General) ,QH301-705.5 ,Genetics ,QH426-470 - Abstract
Brown-marbled grouper is one of the most important mariculture species in China and is widely used as a crossbreeding parent in the grouper industry. Enhancing growth rates is a key target in fish breeding, and gaining insight into the underlying mechanisms responsible for growth differences between individuals can aid in the improvement of grouper growth rates. However, the mechanism behind growth differences in this fish remains unclear. We analyzed the transcriptome profiles of muscle tissues between fast- and slow-growing brown-marbled grouper using RNA-seq and identified 77 significantly up-regulated genes and 92 significantly down-regulated genes in the extreme growth groups. Our findings suggest that up-regulated genes such as ghr and tnni2, as well as down-regulated genes such as stc2 and pdp1, are associated with growth advantages in brown-marbled grouper. We used differentially expressed genes (DEGs) for GO and KEGG enrichment analyses. The results of the GO enrichments showed that the significantly up-regulated genes in the fast-growing group were involved in protein folding, the actin cytoskeleton, the myosin complex, and other processes. The results of the KEGG enrichments showed that the significantly up-regulated genes in the fast-growing group were involved in various pathways such as glycolysis/gluconeogenesis, adipocytokine signaling, MAPK signaling, carbon metabolism, and PI3K-Akt signaling. Additionally, gene set enrichment analysis (GSEA) showed that the PI3K/AKT/mTOR pathway was up-regulated in the fast-growing group, which may be responsible for the higher nutrient absorption efficiency and muscle growth in these fish. Our results contribute to a better understanding of the molecular mechanisms and regulatory pathways underlying fast growth in brown-marbled grouper. However, further studies are necessary to fully elucidate the mechanisms behind growth differences between individuals.
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- 2023
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48. Achieving high strength and high conductivity synergy through hierarchical precipitation stimulated structural heterogeneities in a Cu-Ag-Zr alloy
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Xiang Wu, Jiaxuan Zhang, Richu Wang, Zainab Zafar, Xiaochun Liu, Yujing Liu, Lihua Qian, and Lixin Sun
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Copper alloy ,Hot isostatic pressing ,Hierarchical precipitation-stimulated structures ,Electrical conductivity ,Mechanical property ,Thermal stability ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Cu alloys can be plastically deformed to reach ultra-high strength, but often at an expense of their electrical conductivity. Here we report that the introduction of hierarchical precipitations and the resultant microstructural heterogeneities at different scales could overcome the strength-conductivity tradeoff in Cu-Ag-Zr alloy. The intrinsic particle size dependent precipitation behavior, owing to the different cooling rate during powder atomization, has been inherited after hot isostatic pressing (HIP) of powders into bulk sample. The following cold rolling and aging created multi-scale structures with the sub-micron particles at grain boundaries and sub-micron-to-nano scale precipitates in the grain interior. Those introduced heterogeneous precipitate configurations also altered the evolution of deformation structures during cold rolling and aging, with partially recrystallized grains embedded in highly deformed matrix featured by high density of dislocation and substructures, which results in an excellent combination of tensile strength (704 MPa), electrical conductivity (88.7% IACS), and tensile elongation (14.9%). Besides, no significant coarsening in the micro-nano structures is observed after annealing at 450 °C for 1 h. The findings in this work proposed a novel approach for designing high-strength, high-conductivity, and high-thermal stability copper alloys based on hierarchical precipitation-stimulated structures at nano-to-micron scale.
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- 2022
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49. The plasma D-dimer trends and their value in acute lower limb ischemia patients treated by catheter directed thrombolysis
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Xiaochun Liu, Hailiang Xie, Guofu Zheng, and Yuanfei Liu
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Medicine ,Science - Abstract
Abstract To investigate the change trends of plasma D-dimer during catheter-directed thrombolysis (CDT) in acute lower limb ischemia (ALI) patients and their clinical value. A retrospective review of patients with ALI who received CDT was carried out. The repeated measurements of plasma D-dimer were analyzed by generalized estimating equations (GEEs) and the change trends of D-dimer were analyzed by spline regression approach. A total of 150 patients were included. Among them, 3 days of CDT was ineffective in 41 cases, effective in 33 cases and markedly effective in 76 cases. The results of GEEs analysis showed that serum D-dimer changed significantly with time (time effect, P
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- 2021
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50. Experimental Study on the Influence of Transverse Crack on Chloride Ingress in Concrete Slab Track of High-Speed Railway
- Author
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Xiaochun Liu, Haihua Li, Min Qi, Yiyi Yang, Zhihui Zhu, and Zhiwu Yu
- Subjects
concrete slab ,slab track ,chloride diffusion ,transverse crack ,drying-wetting cycles ,durability ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
The concrete track slab and the base slab of the high-speed railway CRTS II track structure are prone to transverse cracks in the initial service period, which are subjected to environmental action and train load. In order to investigate the influence of transverse cracks on chloride ingress of concrete track slab and base slab in a coastal environment, drying-wetting cycle chloride erosion tests were carried out on reinforced concrete track slab and base slab specimens with cracks ranging from 0 mm to 0.6 mm, subjected to continuous bending moment. The chloride ion concentration of concrete along the depth direction was collected during the test process. The experimental results show that the chloride ion concentration of concrete at the crack section is much higher than that at the intact section, and it increases with the increase of crack width in the range of 0.2 mm to 0.6 mm. A chloride diffusion coefficient model of cracked concrete is proposed for slab track based on the experimental results, which can comprehensively consider the effects of surface chloride ion concentration, chloride binding effect, time-varying effect, temperature, relative humidity, and transverse crack width.
- Published
- 2023
- Full Text
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