bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical Factors for Predicting Neurophysiological Improvements Upon Extension and Flexion in Cervical Spondylotic Myelopathy Patients: A Retrospective Cohort Study
Authors: Yu Zhengran , Chen Jiacheng , Cheng Xing , Zou Zhiyuan , Xie Dingxiang , Chen Yuguang , Zou Xuenong , Peng Xinsheng 
Published: March 2021

Abstract
BackgroundCervical extension and flexion are generally thought to be harmful to CSM patients. Contrary to previous notions, a proportion of CSM patients presented DSSEP improvement upon extension and/or flexion. This study aims to determine the prediction criteria for DSSEP improvement upon extension and flexion with clinical and neutral-position imaging.MethodsCSM patients between 2015 and 2019 were retrospectively evaluated. The recorded outcomes were DSSEP changes upon extension and flexion, disease duration, modified Japanese Orthopedic Association (mJOA) score, gait impairment presence, weakness of upper limb muscles, and positive Hoffmann sign designation. The collection of MRI data included the compression ratio, the number of stenotic levels, the Mühle stenosis grade and disc degeneration stage of the most severe segment, and the presence of ligamentum flavum hypertrophy and intramedullary T2WI hyperintensity. Cervical alignment types were evaluated on plain cervical lateral radiographs.ResultsForty-nine patients were finally enrolled. Nine (18.4%) and 11 (22.4%) patients showed DSSEP improvement upon extension and flexion, respectively. Logistic regression analysis showed that an involved segment number ≤ 2 (P=0.018) and a straight/sigmoid cervical alignment (P=0.033) were significant criteria for predicting DSSEP improvement upon extension (probability: 85.7%). Mühle grade 3 (P=0.022) and disease duration ≤ 6 months (P=0.04) were significant criteria for predicting improvement upon flexion (probability: 85.7%).ConclusionsCervical extension and flexion might not necessarily cause deterioration and can even improve some CSM patients' neurological function at DSSEP examination. The involved segment number and cervical alignment were related to extension DSSEP improvement, while the stenosis grade and disease durations were related to flexion improvement. Our work suggests potential significance of educating CSM patients on maintaining individualized neck positions based on their clinical and radiographic findings.BaTrial registrationThe trial was retrospectively registered on April 30th, 2020 and the registration number is "[2020]151".
Mammographic breast density and survival in women with invasive breast cancer
Authors: Pizzato Margherita , Carioli Greta , Rosso Stefano , Zanetti Roberto , Vecchia Carlo La 
Published: March 2021

Abstract
Purpose: Mammographic breast density (BD) is strongly associated to breast cancer (BC) risk; however, its association with survival is unclear.Methods: Using data from the Piedmont Cancer Registry (Registro Tumori Piemonte), we identified 693 women diagnosed with primary invasive BC between 2009-2014. We applied the Kaplan-Meier method to estimate overall survival in strata of BD and the log-rank test to assess survival differences. We evaluated the hazard ratios (HRs) of death using Cox proportional hazards model and HRs of BC-related and other causes of death using the cause-specific hazards regression model. Models included terms for BD (assessed according to the Breast Imaging Reporting and Data System [BI-RADS] density classification) and were adjusted for selected patient and tumour characteristics.Results: There were102 deaths, of which 49 were from BC. After 5 years, the overall survival was 70% in women with BI-RADS 1, 85% in those with BI-RADS 2, about 95% in those with BI-RADS 3-4 (p <0.01). As compared to women with low BD (BI-RADS 1), the adjusted HRs of death was 0.71 (95% confidence interval (CI) 0.44–1.14) for BI-RADS 2 and 0.38 (95% CI 0.18–0.80) for BI-RADS 3-4 (p for trend = 0.010). As compared to BI-RADS 1, the adjusted HRs of BC-related death decreased with increasing BI-RADS BD from 0.90 (95% CI 0.43–1.87) for BI-RADS 2 to 0.32 (95% CI 0.12–0.91) for BI-RADS 3-4 (p for trend = 0.047). Conclusion: In women with BC, low BD has a negative prognostic impact.
Soil Microbial Communities Altered by Titanium Ions in Different Agroecosystems of Pitaya and Grape
Authors: He Yuan , Ma Xinrong , Hou Xin-Yi , Li Cai-Xia , Wang Yan 
Published: March 2021

Abstract
Titanium ions can significantly promote plant growth, but it is unclear whether the application of titanium ions to plants has any effect on the soil microbial community. In this study, we conducted field surveys to determine the effect of titanium ions on soil microbial communities of the pitaya and grape plantations in Panxi area by performing full-length 16S rRNA gene and ITS amplicon sequencing using PacBio Sequel. The results showed that the application of titanium ions significantly altered the composition and structure of soil microbiota. Root irrigation with titanium ions in pitaya garden, the diversity of soil fungi was significantly reduced. Although there was no statistically significant difference, bacterial diversity also declined. While, the foliar spray of titanium ions on grapes greatly reduced the soil microbial diversity. Moreover, the soil microbiota had a core of conserved taxa, and their relative abundances were significantly altered by titanium ions. Moreover, titanium ions enhanced the cooccurrence relationships and probably improved the stability of the soil microbial community. Our results highlight the different responses of bacterial and fungal communities to titanium ions and sites and provides a basis for the application of titanium ions in plant farming.
Nanocrystalline α-Fe2O3: A Superparamagnetic Material for w-LED Application and Waste Water Treatment
Authors: Gaidhane Mahesh , Taikar Deepak , Gaidhane Pravin , Nagde Kalpana 
Published: March 2021

Abstract
Nanocrystalline α-Fe2O3 is synthesized by sol-gel technique. The prepared nanomaterial was characterized by X-ray diffraction (XRD), SEM, TEM, Fourier Transform Infrared (FTIR) spectroscopy, Vibrating Sample Magnetometry (VSM) and photoluminescence (PL) techniques. X-ray powder diffraction analysis confirmed the formation of α-Fe2O3. Electron microscopy showed spherical morphologies with an average particle size of 30-40 nm. The magnetic property of the prepared material was studied by VSM at room temperature. VSM study shows superparamagnetic nature of the synthesized nanoparticles. Photoluminescence (PL) emission spectra show intense broad emission band centered at 570 nm with 393 nm excitation indicating its usefulness for w-LED application. The CIE-chromaticity color coordinates of prepared material were calculated. The photocatalytic activity of the α-Fe2O3 nanoparticles was analyzed and the nanopowder exhibited good photocatalytic activity for the removal AO7 from its aqueous solution.
Thermal Error Prediction of Ball Screws Based on PSO-LSTM
Authors: Gao Xiangsheng , Guo Yueyang , Hanson Dzonu Ambrose , Liu Zhihao , Wang Min , Zan Tao 
Published: March 2021

Abstract
Thermal error of ball screws seriously affects the machining precision of CNC machine tools especially in high speed and precision machining. Compensation technology is one of the most effective methods to address the thermal issue, and the effect of compensation depends on the accuracy and robustness of the thermal error model. Traditional modeling approaches have major challenges in time-series thermal error prediction. In this paper, a novel thermal error model based on Long Short-Term Memory (LSTM) neural network and Particle Swarm Optimization (PSO) algorithm is proposed. A data-driven model based on LSTM neural network is established according to the time-series collected data. The hyperparameters of LSTM neural network are optimized by PSO and then a PSO-LSTM model is established to precisely predict the thermal error of ball screws. In order to verify the effectiveness and robustness of the proposed model, two thermal characteristic experiments based on step and random speed are conducted on a self-designed test bench. The results show that the PSO-LSTM model has higher accuracy compared with the RBF model and BP model with high robustness. The proposed method can be implemented to predict the thermal error of ball screws, and provide a foundation for thermal error compensation.
A Novel Error Equivalence Model on the Kinematic Error of the Linear Axis of High-End Machine Tool
Authors: LI Xinxin , Li Zhi-Min , Jin Sun , Zhang Jichang , Ding Siyi , Niu Zhihua 
Published: March 2021

Abstract
The kinematic errors of the linear axis play a key role in machining precision of high-end CNC (Computer Numerical Control) machine tool. The quantification of error relationship is still an urgent problem to be solved in the assembly process of the linear axis, especially considering the effect of the elastic deformation of rollers. A systematic error equivalence model of slider is proposed to improve the prediction accuracy for kinematic errors of the linear axis which contains the base, the linear guide rail and carriage. Firstly, the geometric errors of assembly surface of linear guide rail are represented by small displacement torsor. According to the theory of different motion of robots, the error equivalence model of a single slider is established, namely the geometric error of assembly surface of linear guide rail and the pose error of slider is equivalent to the elastic deformation of roller. Based on the principle of vector summation, the kinematic error of a single slider is mapped to the carriage and the kinematic error of the linear axis is obtained. Besides, experiments validation of kinematic error model of the linear axis is carried out. It is indicated that the proposed model is accurate and feasible. The proposed model can provide an accurate guidance for the manufacturing and operation performance of the linear axis in quantification, and a more effective reference for the engineers at the design and assembly stage.
Valorisation of chicken feather fibres in developing poly (vinyl chloride) biocomposites
Authors: Touatou Soumia , Belhaneche-Bensemra Naima 
Published: March 2021

Abstract
The aim of this paper is the valorisation of fibres obtained from chicken feathers in developing new poly (vinyl chloride) (PVC) biocomposites. Feather fibres were first characterized by thermogravimetric analysis and scanning electron microscopy. Then, semi-rigid and flexible PVC biocomposites were prepared by varying the fibre (5, 10 and 15 wt %) and plasticizer (15, 30, 45, 60 wt %) contents. The density, mechanical, thermal and morphological properties of the composites were investigated. The water absorption was determined at two temperatures (23 and 60°C). The results showed the influence of fibre and plasticizer contents on the considered properties.
Identification of Potential Key Genes in Anaplastic Thyroid Cancer Using Bioinformatics AnalysisIdentification of Potential Key Genes in Anaplastic Thyroid Cancer using Bioinformatics Analysis
Authors: Li Zhenzhen , Xiong Chaoliang , Wei Jin , Chen Ping , Zhang Yanping , Zhu Huange , Zhao Yuqi , Lu Wei , He Qian , Geng Yan , Zhu Jianhong 
Published: March 2021

Abstract
BackgroundAnaplastic thyroid cancer (ATC) has a high degree of malignancy and a poor prognosis. Its incidence accounts for approximately 10-15% of all thyroid cancers. The purpose of this study was to determine the differentially expressed genes (DEGs) of ATC through biometric analysis technology, clarify the potential interactions between them, and screen genes related to the prognosis of ATC.MethodsThe GSE29265, GSE65144, GSE33630, and GSE85457 expression profiles downloaded from the Gene Expression Omnibus database (GEO) contained a total of 117 tissue samples (81 normal thyroid tissue samples and 36 ATC samples). The four datasets were integrated and analyzed by the limma packages to obtain DEGs. With these DEGs, we performed gene ontology functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway analyses using the Database for Annotation, Visualization and Integrated Discovery, protein-protein interaction (PPI) analysis using Cytoscape, and survival analysis using the Kaplan-Meier (KM) plotter.Results.After R integration analysis of the four datasets, 764 DEGs were obtained, i.e., 314 upregulated and 450 downregulated genes. Among the hub DEGs obtained in the PPI network, the expression levels of thymidylate synthase (TYMS), fibronectin 1, chordin-like 1, syndecan 2, integrin alpha 2, collagen type I alpha 1 chain, collagen type IX alpha 3 chain (COL9A3), and collagen type XXIII alpha 1 chain (COL23A1) were associated with ATC prognosis. These results showed that the overall survival and recurrence-free survival of TYMS, COL9A3, and COL23A1 were statistically significant in our KM plotter survival analysis; thus, these DEGs may be used as potential biomarkers of ATC.ConclusionThis study identified several potential target genes and pathways that may affect the development of ATC. These findings provide new insights for the detection of novel diagnostic and therapeutic biomarkers for ATC.
Efficient Access to Aliphatic Esters by Photocatalyzed Alkoxycarbonylation of Alkenes
Authors: Chen Jian-Qiang , Tu Xiaodong , Tang Qi , Li Ke , Xu Liang , Wang Siyu , Ji Mingjuan , Wu Jie 
Published: March 2021

Abstract
Aliphatic esters are essential constituents of biologically active compounds and versatile chemical intermediates for the synthesis of drugs. However, their preparation from readily available olefins remains challenging. In this report, a new strategy to access aliphatic esters from olefins through a unique photocatalyzed alkoxycarbonylation reaction is described. Alkyloxalyl chlorides, generated in situ from the corresponding alcohols and oxalyl chloride, are engaged for the first time as alkoxycarbonyl radical fragments under photoredox catalysis. This transformation tolerates a broad scope of electron-rich and electron-deficient olefins and provides the corresponding β-chloro esters in good yields. Additionally, a formal β-selective alkene alkoxycarbonylation is developed. And, a variety of oxindole-3-acetates and furoindolines are prepared in good to excellent yields. A more concise formal synthesis of (±)-physovenine is accomplished as well. With these strategies, a wide range of natural-product-derived olefins and alkyloxalyl chlorides are also successfully employed.
Stent-in-stent technique under fluoroscopy for removal of embedded esophageal stent
Authors: Wang Shuai , Yin Meipan , Ma Yaozhen , Wang Meng , Tong Yalin , Zhao Yue , Li Xiaobing , Xie Pengfei , Wu Gang 
Published: March 2021

Abstract
Background: Treatment of complications after esophageal stent placement and methods for removal of stents need to be improved. The purpose of this study was to evaluate the safety and efficacy of stent-in-stent (SIS) removal of esophageal stent under fluoroscopy.Methods: This study retrospectively analyzed the clinical data of consecutive patients undergoing esophageal stent removal by SIS under fluoroscopy. Under awake condition, local anesthesia, and fluoroscopic monitoring, a second esophageal stent was placed in the first esophageal stent. Four weeks later, both esophageal stents were removed by the SIS technique under fluoroscopy.Results: A total of 12 patients were treated by the SIS removal technique. In 10 patients, the first esophageal stent was easily removed by the SIS method; in the other 2 patients, stent fracture occurred, and some residual nitinol wire had to be removed endoscopically. No serious complications occurred in any patient.Conclusions: The SIS removal technique appears to be a safe and effective method for removal of embedded esophageal metallic stents.
Aliphatic Extractive Effects on Acetic Acid Catalysis of Typical Agricultural Residues to Xylo-Oligosaccharide and Enzymatic Hydrolysability of Cellulose
Authors: Guo Jianming , Huang Kaixuan , Cao Rou , Zhang Junhua , Xu Yong 
Published: March 2021

Abstract
Background: Xylo-oligosaccharide is the spotlight of functional sugar that improves economic benefits of lignocellulose biorefinery. Acetic acid acidolysis technology provides a promising application for xylo-oligosaccharide commercial production, but it is restricted by the aliphatic (wax-like) compounds, which cover the outer and inner surfaces of plants. Results: We removed aliphatic compounds by extraction with two organic solvents. The benzene-ethanol extraction increased the yield of acidolyzed xylo-oligosaccharides of corncob, sugarcane bagasse, wheat straw, and poplar sawdust by 14.79%, 21.05%, 16.68%, and 7.26% while ethanol extraction increased it by 11.88%, 17.43%, 1.26%, and 13.64%, respectively. Conclusion: The single ethanol extraction was safer, more environmentally-friendly and more cost-effective than benzene-ethanol solvent. In short, organic solvents extraction provided a promising auxiliary method for the selective acidolysis of herbaceous xylan to xylo-oligosaccharides, while it had minimal impact on woody poplar.
A New Family of Copper-based MXenes
Authors: Perez Rodrigo Ponce , Ojeda Sandra Gutierrez , Guerrero-Sanchez Jonathan , Armenta Maria Moreno 
Published: March 2021

Abstract
In this work, we demonstrate, through first-principles calculations, the existence of a new family of copper-based MXenes. These add up new structures to the previously reported universe and span the interest of such 2D materials for applications in heterogeneous catalysis, ion-based batteries, sensors, biomedical applications, and so on. First, we propose the MXene-like structures: Cu2N, Cu2C, and Cu2O. Phonon spectra calculations confirmed their dynamical stability by showing just positive frequencies all through the 2D Brillouin zone. The new MXenes family displays metallic characteristics, mainly induced by the Cu-3d orbitals. Bader charge analysis and charge density differences depict bonds with ionic character in which Cu is positively charged, and the non-metal atom gets an anionic character. Our results lay the foundations for the experimental realization of a new MXenes family.
TBX2 Regulates Proliferation, Apoptosis, and Cholesterol Generation of Bovine Through Maintaining Mitochondrial Function and Autophagy in Bovine Cumulus Cell
Authors: Li Sheng-Peng , Xie Wen-Yin , Yu Wen-Jie , Peng Yan-Xia , Liu Chang , Liu Zi-Bin , Cai Xiao-Shi , Chen Cheng-Zhen , Yuan Bao , Kim Nam-Hyung , Jiang Hao , Zhang Jia-Bao 
Published: March 2021

Abstract
TBX2 is a member of T-box gene family whose members are highly conserved in evolution and encoding genes are involved in the regulation of developmental processes. The encoding genes play an important role in growth and development, but its regulatory effects in bovine cumulus cells are still unclear. In this study, the changes of cell physiological function were detected after TBX2 gene was knocked down. Compared with the control group, when TBX2 was inhibited, the levels of autophagy, apoptosis and reactive oxygen species in cumulus cells were increased, the proliferation, expansion ability and the amount of cholesterol secreted by cells were significantly decreased, and the cell cycle was also disrupted. The results showed that TBX2 could regulate the normal physiological activities of bovine cumulus cells.
Investigation and Analysis of Green Refrigerant Zero ODP as an Alternative Refrigerant Lower Cost and GWP
Authors: Saengsikhiao Piyanut , Taweekun Juntakan , Maliwan Kittinan 
Published: March 2021

Abstract
This research presents the results of investigation and analysis of the environmentally friendly refrigerant for R22 replacement. All refrigerant properties in this research were based on results from the REFPROP and CYCLE_D-HX software of NIST under CAN/ANSI/AHRI540. The results of this work show that HCs R170, R290, R600, R600a, R601, R601a, R1150 and R1270 can be mixed in HFCs R417A, R417B, R422A, R422B, R422C, R422D, R424A, R437A, R438A and R453A and able to be further developed in the future. All refrigerants are non-flammable refrigerants, non-toxic and zero ODP. The R453A mixed with HCs R600 (0.6%) and R601a (0.6%) and is COPc refrigerant close to that of R22 refrigerant. In conclusion, it can be used as an environmentally friendly and energy efficiency replacement for R22. All refrigerants are also refrigerants that are matched with the 4th generation refrigerants with the use of natural refrigerants.
Medical internship training during the COVID-19 pandemic – a case of ‘sacrificial pawns’ or not?
Authors: Singaram Veena S , Naidoo Kimesh , Ramrathan Labby 
Published: March 2021

Abstract
Background Newly qualified medical practitioners (interns) in South Africa (SA) are part of the frontline healthcare workers who face Africa’s most severe COVID-19 pandemic within an environment already burdened with tuberculosis, HIV and trauma epidemics. The experiences of interns during the pandemic reflect SA’s preparedness to respond in a crisis and inform strategies that could be adopted to balance training and service in resource-challenged contexts. This study explored the strengths, weaknesses, opportunities and threats posed by the COVID-19 pandemic as reflected on by interns within clinical training platforms in SA.Methods An online survey tool consisting of ten open-ended questions based on the SWOT framework related to personal and professional perspectives to clinical training during the COVID-19 pandemic was developed using SurveyMonkey. Due to lockdown restrictions, all data were collected remotely with the survey instrument being distributed via the social media platform WhatsApp. Three coders thematically analysed data until consensus was reached.Results Forty-six first- and second-year interns reflected on personal and systemic challenges as the major threats and weaknesses in intern training during the COVID-19 pandemic. Extrapolating on strengths and opportunities, there were three overarching learnings interns reflected on. These related to being a medical professional, being in a learning environment, and specific learnings realised. Existing challenges in the environment exacerbated the threats posed by COVID-19 and innovative strategies related to improving support, feedback and broadening the intern curriculum were identified. In addition, the use of online training around holistic care and intern evaluation was mooted as an innovation to develop out of this pandemic.Conclusion Although the clinical environment where interns learn and work is often stressful and overpowered by high service burdens, there are unique opportunities to enhance self-directed learning and graduate competencies, even in the midst of the COVID-19 pandemic.