170 results on '"Kai Si"'
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2. The role communication, informativeness, and social presence play in the social media recruitment context of an emerging economy
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Kai Si, Tariq Jalees, Syed Imran Zaman, Syed Hasnain Alam, and Sherbaz Khan
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social-media effectiveness ,social media presence ,informativeness ,communication and recruitment process ,Business ,HF5001-6182 ,Management. Industrial management ,HD28-70 - Abstract
AbstractBoth individuals and organizations extensively use the internet and social media for communications and other purposes in the present era. The study examines the impact of social media effectiveness on informativeness and communication. It also explores the effect of informativeness and communication on the recruitment process. The study also examined the mediating roles of informativeness and communication and the moderating role of social presence. The study has focused on the banking sector of Karachi, Pakistan. The study’s enumerators distributed 450 questionnaires to the HR departments of the targeted banks and received 427 valid questionnaires. For data analysis, the study used Smart PLS version 3.2. It includes reliability, validity analyses, and generating a structural model for testing the hypotheses. The study’s results support seven hypotheses and reject one hypothesis. The study found that social media positively affect informativeness, communication, and recruitment. The study also validated the (i) mediating role of informativeness on social media effectiveness and (ii) the mediating role of communication on social media effectiveness and recruitment process. The study also supported the positive moderating roles of social presence on informativeness and the recruitment process, but it failed to support that social presence positively moderates communication and the recruitment process.
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- 2023
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3. Numerical Simulation and Evaluation on Continuum Damage Models of Rocks
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Leilei Zhao, Zhendong Cui, Ruidong Peng, and Kai Si
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rock damage ,numerical simulation ,damage variable ,stress-strain curve ,strain softening ,Technology - Abstract
Damage mechanics play an important role in the analysis of rock deformation and failure. Numerous damage variables have been proposed and the corresponding continuum damage models were suggested. Knowing how to apply these theoretical models appropriately in numerical simulations is the key to whether they can be adopted to solve practical problems. The continuum damage models were grouped into empirical damage models, statistical damage models, and elastoplastic damage models in this article. Their applicability and limitations were studied according to some numerical simulations of the most basic uniaxial compression test of a cylinder rock sample. Three representative damage models were chosen from the literature and applied to FEM numerical simulations by introducing a self-developed program. The stress-strain curves due to damage were obtained from the numerical simulation results and compared to those from the experimental results. The damage distribution and evolution of different damage models were investigated to evaluate their influences on rock deformation. It can be concluded that strain-softening stages presented by both the empirical damage models and the statistical damage models are caused by subtracting the elastic modulus gradually while those presented by the elastoplastic damage models are caused by reducing plastic yield stress gradually. Damage-elastic coupling cannot well reflect the irreversibility of damage. The elastoplastic damage models combine damage with plastic history, and thus the irreversibility of damage can be represented. Furthermore, the compulsory reduction of the elastic modulus can probably lead to extreme element distortion and even an unreasonable negative modulus when damage is very serious, which inevitably causes the numerical simulation to fail prematurely under complex stress states. Although the elastoplastic damage models are recommended at present rather than the other models, a more appropriate definition of the damage variable can be expected that should track the whole deformation and failure process. Knowing how to treat the adverse effect of local deterioration due to damage is the challenge numerical simulations have to face when they are applied in the actual project with complex stress states.
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- 2022
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4. Study on Fatigue Life Prediction and Acoustic Emission Characteristics of Sandstone Based on Mesoscopic Crack Propagation Mechanism
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Kai Si, Zhendong Cui, Ruidong Peng, and Leilei Zhao
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sandstone ,rock fatigue life ,mesoscopic crack propagation ,acoustic emission ,Technology - Abstract
Even when the maximum stress is less than the peak stress under conventional loading, fatigue failure of rock is likely to occur, thereby showing its unique characteristics. The present study summarized the factors affecting rock fatigue life from the perspective of phenomenology and studied the fatigue damage process of rock from the microscopic perspective. However, the meso-mechanical mechanism of fatigue–tension failure of rocks is still not very clear, and there are few studies on rock fatigue life that use meso-crack propagation models. In this paper, a mesoscopic model considering wing crack propagation is introduced to examine the fatigue failure of sandstone. A fatigue life prediction formula of sandstone was deduced via a combination with the Paris formula. This formula can quantitatively characterize the impact of upper limit stress and lower limit stress on the fatigue life of sandstone and explain the reason why upper limit stress has a greater influence on the fatigue process of sandstone. Such a prediction formula is applicable only under the condition of low confining pressures, which mainly cause tensile failure due to mesoscopic wing crack propagation. Acoustic emission signals during fatigue failure were monitored and then analyzed using a clustering method and a moment tensor inversion method. Therefore, the tensile or shear properties of mesoscopic failure could be distinguished according to acoustic emission characteristics in different stages of fatigue crack propagation. The results showed that crack sources causing sandstone fatigue failure are mainly tension-type when confining pressure is less than 10 MPa, which further verifies the proposed prediction model of sandstone fatigue life under low confining pressures.
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- 2022
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5. Numerical Simulation on Mesoscale Mechanism of Seepage in Coal Fractures by Fluid-Sloid Coupling Method
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Kai Si, Ruidong Peng, Leilei Zhao, Yan Zhao, Yaheng Zhu, Zhendong Cui, and Jianyong Zhang
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Geology ,QE1-996.5 - Abstract
Trying to reveal the mechanism of gas seepage in coal is of significance to both safe mining and methane exploitation. A series of FEM numerical models were built up and studied so as to explore the mesoscale mechanism of seepage in coal fractures. The proposed mesoscale FEM model is a cube with micron fractures along three orthogonal directions. The distribution of velocity and pressure under fluid-solid coupling was obtained, and furthermore, the seepage flow flux and an equivalent permeability of the whole model were calculated. The influences of fracture width, outlet velocity, and in situ stress level on seepage were investigated. The numerical results show that nonlinear Darcy seepage occurs during low velocity zone. The permeability is increased linearly with the increasing of facture width and outlet velocity. A certain change of lateral coefficient of in situ stress also affects seepage. The permeability is increased sharply once deviating the isotropic spherical stress state, but it is no longer changed obviously after the lateral coefficient has been increased or decreased more than 20%. The mesoscale seepage mechanism in coal fractures has been preliminarily revealed by considering fluid-solid coupling effect, and the key factors influencing fluid seepage in coal fractures were demonstrated. The proposed methods and results will be helpful to the further study of seepage behaviour in coal with more complex structures.
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- 2021
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6. Comparative Study on Mineral-Scale Microcrack Propagation of Shale under Different Loading Methods
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Jianyong Zhang, Zhendong Cui, Weige Han, Kai Si, and Yan Zhao
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Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Producing a sufficient volume of multiscale crack networks is key to enhancing recovery of shale gas. The formation of crack network largely depends on initiation and propagation of microcracks. To reveal the influence of different loading methods on the propagation of mineral-scale microcracks, this study used the Voronoi tessellation technique to establish a cohesive zone model of shale mineral distribution and applied six different boundary conditions to represent different loading methods. Crack path characteristics, rupture characteristics, continuous crack propagation and turning, and en echelon intermittent crack propagation under different loading methods were compared and analyzed. The essence of different loading methods affecting the length and complexity of cracks was the spreading range of tensile microcracks. The mechanical properties of minerals led to dissimilarities in continuous crack propagation and turning. The formation and propagation of en echelon intermittent fractures of different scales were mainly impacted by the heterogeneity of minerals and mineral aggregates. The spreading direction and connection form of en echelon intermittent fractures were mainly affected by the loading method. Conclusions arising from mineral-scale simulations contribute to understanding the mechanism of microcrack propagation resulting from different loading methods, and these conclusions have a guiding significance to enhanced shale gas recovery.
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- 2021
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7. The Structural Characteristics of an Acidic Water-Soluble Polysaccharide from Bupleurum chinense DC and Its In Vivo Anti-Tumor Activity on H22 Tumor-Bearing Mice
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Shuyuan Shi, Mengli Chang, Huiping Liu, Suyun Ding, Zhiqian Yan, Kai Si, and Tingting Gong
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polysaccharide ,Bupleurum chinense DC ,characterization ,anti-tumor activity ,Organic chemistry ,QD241-441 - Abstract
This study explored the preliminary structural characteristics and in vivo anti-tumor activity of an acidic water-soluble polysaccharide (BCP) separated purified from Bupleurum chinense DC root. The preliminary structural characterization of BCP was established using UV, HPGPC, FT-IR, IC, NMR, SEM, and Congo red. The results showed BCP as an acidic polysaccharide with an average molecular weight of 2.01 × 103 kDa. Furthermore, we showed that BCP consists of rhamnose, arabinose, galactose, glucose, and galacturonic acid (with a molar ratio of 0.063:0.788:0.841:1:0.196) in both α- and β-type configurations. Using the H22 tumor-bearing mouse model, we assessed the anti-tumor activity of BCP in vivo. The results revealed the inhibitory effects of BCP on H22 tumor growth and the protective actions against tissue damage of thymus and spleen in mice. In addition, the JC-1 FITC-AnnexinV/PI staining and cell cycle analysis have collectively shown that BCP is sufficient to induce apoptosis and of H22 hepatocarcinoma cells in a dose-dependent manner. The inhibitory effect of BCP on tumor growth was likely attributable to the S phase arrest. Overall, our study presented significant anti-liver cancer profiles of BCP and its promising therapeutic potential as a safe and effective anti-tumor natural agent.
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- 2022
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8. Crack Propagation Process and Seismogenic Mechanisms of Rock Due to the Influence of Freezing and Thawing
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Kai Si, Zhendong Cui, Ruidong Peng, Leilei Zhao, and Yan Zhao
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freeze–thaw damage ,fracture process ,acoustic emission ,signal processing ,AE moment tensor ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
A common problem in cold regions is the influence of freeze–thaw damage on the stability of rock engineering. Therefore, a series of uniaxial compression tests of sandstone after freeze–thaw treatment was carried out in this study. The purpose was to express the initial damage of rock after freezing and thawing treatment more quantitatively and to study the influence of freeze–thaw damage on the rock crack growth process to provide some reference for the stability evaluation of rock engineering in cold regions. The results showed that the number of freeze–thaw cycles and the lowest freeze–thaw temperature had a significant effect on the rock damage and characteristic stress value, and the number of cycles had a more obvious effect: with an increase in the number of freeze–thaw cycles and a decrease in the freeze–thaw temperature, the initial damage DNT had an increasing trend. In addition, the intrinsic mechanism of the freeze–thaw effect on the rock characteristic stress was explained from the perspective of a meso-mechanical mechanism. From the inversion results of the acoustic emission (AE) moment tensor, it was found that the proportion of tensile cracks gradually increased with the increase in the initial damage of the rock in the stable and unsteady stages of the rock crack propagation.
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- 2021
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9. Trehalose promotes functional recovery of keratinocytes under oxidative stress and wound healing via ATG5/ATG7
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Jin, Jian, Zhu, Kai-si, Tang, Shu-min, Xiang, Yang, Mao, Ming-yi, Hong, Xu-dong, Chen, Ai-fen, Zhang, Xu-dong, Lu, Hao, Chen, Zheng-li, Wu, Jin-fang, Pan, Sun-feng, and Zhu, Shi-hui
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- 2023
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10. Comprehensive chemical study on different organs of cultivated and wild Sarcandra glabra using ultra-high performance liquid chromatography time-of-flight mass spectrometry (UHPLC-TOF-MS)
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WANG, Cai-Yun, LU, Jing-Guang, CHEN, Da-Xin, WANG, Jing-Rong, CHE, Kai-Si, ZHONG, Ming, ZHANG, Wei, and JIANG, Zhi-Hong
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- 2021
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11. An improved fixture for better measuring the displacements and mode‐I fracture toughness of chevron bend specimens
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Zhendong Cui, Tao Wei, Leilei Zhao, and Kai Si
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Mechanics of Materials ,Mechanical Engineering ,General Materials Science - Published
- 2023
12. How Does a Smart City Bridge Diversify Urban Development Trends? A systematic Bibliometric Analysis and Literature Study
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Dong Qiu, Binglin Lv, Calvin M. L. Chan, Yuesen Huang, and Kai Si
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inclusive city ,bibliometric ,smart city ,Renewable Energy, Sustainability and the Environment ,low-carbon city ,Geography, Planning and Development ,sponge city ,resilient city ,Building and Construction ,Management, Monitoring, Policy and Law - Abstract
In recent years, the smart city concept has developed rapidly and has gradually become the most popular urban concept. However, the advent of the new century has been accompanied by the emergence of many other emerging city concepts. For these emerging urban concepts, such as a resilient city, low-carbon city, sponge city, and inclusive city, it needs to be clarified how these concepts relate to a smart city. In this paper, the scientometrics software Pajek was used to analyze the publication activities of the city concept and two-mode keywords co-occurrence network with cities. Meanwhile, the study also explores these concepts’ global development and correlation. Further, it also analyzes the core problems that each city concept addresses through a literature review. It was observed that although the research content of these four city concepts is different from that of smart cities, they are conceptually and technologically connected with them. The development of smart cities can accelerate the smart development of other city concepts. At the same time, it can acquire and absorb more advanced models from other city concepts to enrich itself. The results suggest that the development of city concepts should be more comprehensive to help cities become more inclusive, safe, resilient, and sustainable, which has important implications for urban policy and practice.
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- 2023
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13. Leveraging gene correlations in single cell transcriptomic data
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Kai Silkwood, Emmanuel Dollinger, Joshua Gervin, Scott Atwood, Qing Nie, and Arthur D. Lander
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Single cell RNA sequencing ,Gene–gene correlation ,Gene regulatory network ,Gene co-expression network ,Melanoma ,Computer applications to medicine. Medical informatics ,R858-859.7 ,Biology (General) ,QH301-705.5 - Abstract
Abstract Background Many approaches have been developed to overcome technical noise in single cell RNA-sequencing (scRNAseq). As researchers dig deeper into data—looking for rare cell types, subtleties of cell states, and details of gene regulatory networks—there is a growing need for algorithms with controllable accuracy and fewer ad hoc parameters and thresholds. Impeding this goal is the fact that an appropriate null distribution for scRNAseq cannot simply be extracted from data in which ground truth about biological variation is unknown (i.e., usually). Results We approach this problem analytically, assuming that scRNAseq data reflect only cell heterogeneity (what we seek to characterize), transcriptional noise (temporal fluctuations randomly distributed across cells), and sampling error (i.e., Poisson noise). We analyze scRNAseq data without normalization—a step that skews distributions, particularly for sparse data—and calculate p values associated with key statistics. We develop an improved method for selecting features for cell clustering and identifying gene–gene correlations, both positive and negative. Using simulated data, we show that this method, which we call BigSur (Basic Informatics and Gene Statistics from Unnormalized Reads), captures even weak yet significant correlation structures in scRNAseq data. Applying BigSur to data from a clonal human melanoma cell line, we identify thousands of correlations that, when clustered without supervision into gene communities, align with known cellular components and biological processes, and highlight potentially novel cell biological relationships. Conclusions New insights into functionally relevant gene regulatory networks can be obtained using a statistically grounded approach to the identification of gene–gene correlations.
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- 2024
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14. Health-related quality of life influences surgical decisions in patients with rotator cuff disease: analysis of a randomized controlled trial
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Sanna Cederqvist, Tapio Flinkkilä, Antti Tuominen, Markus Sormaala, Jari Ylinen, Hannu Kautiainen, Kai Sirniö, Konsta Pamilo, Ilkka Kiviranta, Juha Paloneva, and on behalf of the SURFIN group
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shoulder ,rotator cuff disease ,rehabilitation ,health-related quality of life ,shoulder surgery ,36-item short form survey ,surgical treatments ,pain score ,visual analogue scale (vas) ,constant-murley score ,multivariate analysis ,univariate analyses ,Orthopedic surgery ,RD701-811 - Abstract
Aims: Rotator cuff disease (RCD) can considerably decrease quality of life. Here, we investigated whether health-related quality of life (HRQoL) influences the need for surgery in patients with RCD. Methods: We performed an analysis of 417 patients with symptomatic RCD who were recruited from two hospitals between June 2008 and December 2014 to be randomized to receive non-surgical or surgical treatment. After a three-month rehabilitation period, 36-Item Short-Form Health Survey questionnaire (SF-36), shoulder pain (visual analogue scale (VAS)), and shoulder function (Constant-Murley score) data were available from 191 still-symptomatic patients who were eligible for surgery. A control group was formed from 87 excluded patients who were no longer eligible for surgery due to relief of symptoms. Results: Mean pain on the VAS was 51.3 (SD 20.1) in the patients eligible for surgery and 41.7 (SD 21.2) in the control group. The following domains of the SF-36 were associated with being eligible for surgery in univariate analyses: bodily pain, general health, vitality, social functioning, and emotional wellbeing. In multivariate analysis, only bodily pain was associated with pursuing surgical treatment. The RCD population’s values for physical role, bodily pain, and physical functioning were poorer compared to the values of the general population. Conclusion: Lower HRQoL, as indicated by the lower bodily pain score on the SF-36, was associated with the decision to undergo surgical treatment in patients with RCD. Therefore, HRQoL should be considered when determining treatment options for RCD. Cite this article: Bone Jt Open 2024;5(9):793–799.
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- 2024
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15. The role of Type III secretion system in the pathogenesis of Pseudomonas aeruginosa microbial keratitis
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JustinJ Yang, ElizabethP Shen, and Kai-Si Claire Tsuei
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Pseudomonas aeruginosa ,business.industry ,iq-domain gtpase-activating protein 1 ,contact lens ,General Medicine ,medicine.disease ,medicine.disease_cause ,type iii secretion system ,pseudomonas aeruginosa ,Keratitis ,Microbiology ,Type three secretion system ,Pathogenesis ,microbial keratitis ,medicine ,Medicine ,business - Abstract
Pseudomonas aeruginosa is the most commonly isolated Gram-negative pathogen causing sight-threatening microbial keratitis (MK). Contact lens wear is the most significant risk factor associated with pseudomonal MK. Understanding the pathogenesis of MK due to P. aeruginosa and its interactions with contact lenses is crucial in preventing these often rapidly progressive and highly antibiotic-resistant infections. Bacterial virulence factor Type III secretion system (T3SS) has significant interplays between contact lens material, antibiotic sensitivity, disinfectant selectivity, and bacterial cell invasion. Depending on the T3SS exotoxins produced, P. aeruginosa strains are divided into cytotoxic or invasive strains. Cytotoxic strains are relatively resistant to commercial disinfectants, while invasive strains are more antibiotic resistant. Therefore, contact lens wearers are more predisposed to cytotoxic P. aeruginosa infections, and patients with trauma or previous surgery are more prone to infection by invasive strains. Previous studies with mutant P. aeruginosa strains unable to produce T3SS exotoxins were more susceptible to disinfectants and less able to adhere to soft contact lenses, indicating an essential role of T3SS in bacterial virulence. Invasion of P. aeruginosa intracellularly was found to be associated with control of scaffold protein IQ-domain GTPase-activating protein 1 (IQGAP1) and human corneal epithelial cell tight junctions. Knockdown of IQGAP1 strengthened tight junctions that prevented intracellular survival of invasive P. aeruginosa strains and enhanced corneal epithelial cell survival. These novel findings of the vital role of T3SS in the pathogenesis of pseudomonal MKs will provide new guidelines in both prevention and treatment of this common eye-blinding infection.
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- 2022
16. Trehalose promotes functional recovery of keratinocytes under oxidative stress and wound healing via ATG5/ATG7
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Jin, Jian, primary, Zhu, Kai-si, additional, Tang, Shu-min, additional, Xiang, Yang, additional, Mao, Ming-yi, additional, Hong, Xu-dong, additional, Chen, Ai-fen, additional, Zhang, Xu-dong, additional, Lu, Hao, additional, Chen, Zheng-li, additional, Wu, Jin-fang, additional, Pan, Sun-feng, additional, and Zhu, Shi-hui, additional
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- 2022
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17. Analysis of monitoring effect on Hybrid Electric Field for AC/DC Cross Line
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Yang, Yi, primary, Ma, Xue-kai Si, additional, Fang, Shu-bo, additional, Han, Qing, additional, and Zhou, Zan-dong, additional
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- 2022
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18. Trehalose promotes functional recovery of keratinocytes under oxidative stress and wound healing via ATG5/ATG7
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Jian Jin, Kai-si Zhu, Shu-min Tang, Yang Xiang, Ming-yi Mao, Xu-dong Hong, Ai-fen Chen, Xu-dong Zhang, Hao Lu, Zheng-li Chen, Jin-fang Wu, Sun-feng Pan, and Shi-hui Zhu
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Emergency Medicine ,Surgery ,General Medicine ,Critical Care and Intensive Care Medicine - Published
- 2022
19. A differential capacitive sensing circuit for micro-machined omnidirectional microphone.
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Jung-Tang Huang, Kai-Si Chen, and Chu-Che Chien
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- 2011
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20. Comprehensive chemical study on different organs of cultivated and wild Sarcandra glabra using ultra-high performance liquid chromatography time-of-flight mass spectrometry (UHPLC-TOF-MS)
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Jiang Zhi-Hong, Che Kai-Si, Chen Da-Xin, Zhang Wei, LU Jing-Guang, Zhong Ming, Wang Cai-Yun, and Wang Jing-Rong
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Plant Stems ,010405 organic chemistry ,Phytochemicals ,General Medicine ,Biology ,Plant Roots ,01 natural sciences ,Mass Spectrometry ,0104 chemical sciences ,Plant Leaves ,Magnoliopsida ,03 medical and health sciences ,Horticulture ,0302 clinical medicine ,Complementary and alternative medicine ,030220 oncology & carcinogenesis ,Chemical constituents ,Drug Discovery ,Ultra high performance ,Time-of-flight mass spectrometry ,Chromatography, High Pressure Liquid ,Sarcandra glabra - Abstract
To illuminate the similarities and differences between wild and cultivated Sarcandra glabra (S. glabra), we performed a comprehensively study on 26 batches of cultivated S. glabra and 2 batches of wild S. glabra. Chemical constituents and distribution characteristics of roots, stems and leaves in both wild and cultivated S. glabra were investigated through UHPLC-TOF-MS method. The result revealed that there were significant differences between roots, stems and leaves in S. glabra. And the chemical contents in the root part were less or even absence than those in leaf and stem, which suggested the root organ could be excluded as medicine. Meanwhile, the chemical contents of stems and leaves in cultivated S. glabra was sightly higher than that of wild samples. Therefore, cultivated S. glabra may have a high potential for substitution of wild S. glabra without affecting its pharmaceutical properties. In summary, our study could provide important information to the molecular basis for quality control of S. glabra.
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- 2021
21. Numerical Simulation on Mesoscale Mechanism of Seepage in Coal Fractures by Fluid-Sloid Coupling Method
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Ruidong Peng, Zhang Jianyong, Yaheng Zhu, Zhendong Cui, Leilei Zhao, Kai Si, and Yan Zhao
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QE1-996.5 ,Article Subject ,Computer simulation ,business.industry ,Isotropy ,0211 other engineering and technologies ,Mesoscale meteorology ,Geology ,02 engineering and technology ,Mechanics ,Finite element method ,Stress (mechanics) ,Permeability (earth sciences) ,020401 chemical engineering ,Fracture (geology) ,General Earth and Planetary Sciences ,Coal ,021108 energy ,0204 chemical engineering ,business - Abstract
Trying to reveal the mechanism of gas seepage in coal is of significance to both safe mining and methane exploitation. A series of FEM numerical models were built up and studied so as to explore the mesoscale mechanism of seepage in coal fractures. The proposed mesoscale FEM model is a cube with micron fractures along three orthogonal directions. The distribution of velocity and pressure under fluid-solid coupling was obtained, and furthermore, the seepage flow flux and an equivalent permeability of the whole model were calculated. The influences of fracture width, outlet velocity, and in situ stress level on seepage were investigated. The numerical results show that nonlinear Darcy seepage occurs during low velocity zone. The permeability is increased linearly with the increasing of facture width and outlet velocity. A certain change of lateral coefficient of in situ stress also affects seepage. The permeability is increased sharply once deviating the isotropic spherical stress state, but it is no longer changed obviously after the lateral coefficient has been increased or decreased more than 20%. The mesoscale seepage mechanism in coal fractures has been preliminarily revealed by considering fluid-solid coupling effect, and the key factors influencing fluid seepage in coal fractures were demonstrated. The proposed methods and results will be helpful to the further study of seepage behaviour in coal with more complex structures.
- Published
- 2021
22. On properties and operations of complex neutrosophic soft groups
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Fatimah Rahoumah, Kai Siong Yow, Nik Mohd Asri Nik Long, and Menshawi Gasim
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Neutrosophic logic ,Complex neutrosophic soft set ,Complex neutrosophic soft group ,Homogenous neutrosophic soft group ,Mathematics ,QA1-939 - Abstract
Abstract Complex neutrosophic soft groups represent a significant advancement in handling uncertainty by integrating the concepts of fuzzy logic, soft sets, and neutrosophic logic. These groups generalize complex fuzzy soft groups and introduce an additional dimension through neutrosophic membership functions, namely truth, indeterminacy, and falsity. This creates a richer framework for dealing with uncertainty and ambiguity, making it well-suited for managing complex data structures in real-world applications. We explore some important definitions and theoretical frameworks surrounding complex neutrosophic soft groups, highlighting the unique aspect of neutrosophic membership functions. Additionally, we present an overview of neutrosophic soft groups, exploring some of their key operations and fundamental properties. We then examine the basics of homogeneous complex neutrosophic soft sets and their roles in establishing complex neutrosophic soft groups.
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- 2024
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23. Assessing the impact of frailty in elderly patients undergoing emergency laparotomies in Singapore
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Serene Si Ning Goh, Jiashen Zhao, Paul Andrew Drakeford, Qingyan Chen, Woan Wui Lim, Anthony Linajie Li, Kai Siang Chan, Marc Weijie Ong, and Jerry Tiong Thye Goo
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Medicine - Abstract
Introduction: The global rise in ageing populations poses challenges for healthcare systems. By 2030, Singapore anticipates a quarter of its population to be aged 65 or older. This study addresses the dearth of research on frailty’s impact on emergency laparotomy (EL) outcomes in this demographic, emphasising the growing significance of this surgical intervention. Method: Conducted at 2 tertiary centres in Singapore from January to December 2019, a retrospective cohort study examined EL outcomes in patients aged 65 or older. Frailty assessment, using the Clinical Frailty Scale (CFS), was integrated into demographic, diagnostic and procedural analyses. Patient data from Tan Tock Seng Hospital and Khoo Teck Puat Hospital provided a comprehensive view of frailty’s role in EL. Results: Among 233 participants, 26% were frail, revealing a higher vulnerability in the geriatric population. Frail individuals exhibited elevated preoperative risk, prolonged ICU stays, and significantly higher 90-day mortality (21.3% versus 6.4%). The study illuminated a nuanced connection between frailty and adverse outcomes, underlining the critical need for robust predictive tools in this context. Conclusion: Frailty emerged as a pivotal factor influencing the postoperative trajectory of older adults undergoing EL in Singapore. The integration of frailty assessment, particularly when combined with established metrics like P-POSSUM, showcased enhanced predictive accuracy. This finding offers valuable insights for shared decision-making and acute surgical unit practices, emphasising the imperative of considering frailty in the management of older patients undergoing emergency laparotomy.
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- 2024
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24. Computational model development for heat production of Al-CaO flameless ration heaters (FRHs): The effect of temperature, pressure, and pH on the exothermic characteristics
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Chongxin Liu, Kai Si, Magdalena Zielinska, Xinlei Huang, Jiajia Fang, Hong-Wei Xiao, and Chunjiang Zhang
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Microbiology (medical) ,Biomaterials ,Polymers and Plastics ,Safety, Risk, Reliability and Quality ,Food Science - Published
- 2023
25. Combined treatment of lactic acid-ultrasound-papain on yak meat and its tenderization mechanism
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Xiaowei Zhang, Linxian Zhu, Lushan Song, Li Song, Shuyuan Shi, Hai Liu, Jiameng Wu, Kai Si, Tingting Gong, and Huiping Liu
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Meat ,Papain ,Animals ,Cattle ,Lactic Acid ,Cooking ,Food Science ,Ultrasonography - Abstract
The combined effects of lactic acid-ultrasound-papain on yak meat tenderization were investigated, and its tenderization mechanism elucidated. The optimal condition for combined tenderization was obtained with 0.03% lactic acid, ultrasound for 30 mins, and 200 U/g of papain. When compared with the untreated yak meat, the cutting force and the cooking loss of the tenderized yak meat were decreased by 62.16% and 31.25%, respectively, while the myofibrillar fragmentation index increasing 4.3 times. After the combined tenderization, it was observed a loose arrangement of muscle with larger gaps and cavities. The random-coil content of myofibrillar protein increased to 48.3%, while α-helix decreased to 14.4%, indicating that the myofibrillar protein underwent some unfolding and stretching. These results demonstrated that this combined treatment improved the tenderization of yak meat by disrupting muscle integrity, increasing its water-holding capacity, denaturing myofibrillar protein, and changing its spatial structure. The combined process using lactic acid-ultrasound-papain showed some potential to improve meat texture.
- Published
- 2022
26. Dynamic Effect of Shaped Charge Blasting and Its Application in Coal Seam Permeability Enhancement
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Xiangshang Li, Kai Si, Tuan He, and Chunyuan Li
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General Chemical Engineering ,General Chemistry - Abstract
The dynamic effect of shaped charge blasting and its application in coal seam permeability enhancement have been investigated. Comparative experiments of shaped charge blasting and conventional blasting to fracture the concrete are carried out. Then, the propagation characteristics of explosion stress waves under shaped charge blasting and conventional blasting are analyzed by ANSYS/LS-DYNA. Finally, the fracture mechanical model of shaped charge blasting is established. The experimental results show that the width of the four main cracks formed after conventional blasting is 0.3 cm, while the width of the cracks in the energy accumulation direction after shaped charge blasting is 1.1 cm and the width of that in the vertical energy accumulation direction is 0.4 cm. The numerical simulation results show that the crushing area after shaped charge blasting is "dumbbell type", and the area is smaller than that of conventional blasting. However, the cracking area is "spindle type", and the development of the fracture degree is better than that of conventional blasting. In addition, shaped charge blasting is used to improve the permeability of coal seams. The results show that shaped charge blasting effectively improves the permeability and gas extraction rate of coal seams.
- Published
- 2022
27. Binding mechanism and bioavailability of a novel phosvitin phosphopeptide (Glu-Asp-Asp-pSer-pSer) calcium complex
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Kai Si, Tingting Gong, Suyun Ding, Huiping Liu, Shuyuan Shi, Jianqiu Tu, Linxian Zhu, Li Song, Lushan Song, and Xiaowei Zhang
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Phosvitin ,Phosphopeptides ,Calcium, Dietary ,Biological Availability ,Calcium ,General Medicine ,Food Science ,Analytical Chemistry - Abstract
Phosvitin has excellent calcium binding capacity, related to its phosphopeptides. The phosphopeptides may be used as functional ingredients for improving calcium bioavailability, but the calcium-binding mechanism is unclear. In this study, a novel phosvitin phosphorylated pentapeptide (Glu-Asp-Asp-pSer-pSer, EDDpSpS) was selected to prepare an EDDpSpS calcium complex (EDDpSpS-Ca), and the calcium-binding mechanism and bioavailability investigated. The calcium-binding capacity of EDDpSpS was up to 468 ± 152.80 mg/g. Calcium ions prompted the folding of the EDDpSpS structure to form spherical nanoparticles. The calcium binding sites of EDDpSpS involved peptide bonds, carboxyl, amino, and phosphate groups. Molecular forces involved in these interactions were electrostatic in nature. Moreover, EDDpSpS-Ca had excellent bioavailability when compared to CaCO
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- 2022
28. Influence of bonding phases on properties of in-situ bonded porous SiC membrane supports
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Wen-Qing Ao, Wei Han, Kai-kai Si, Kaiqi Liu, and Zhi-Yong Luo
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010302 applied physics ,Quenching ,Thermal shock ,Materials science ,Process Chemistry and Technology ,Mullite ,02 engineering and technology ,Atmospheric temperature range ,021001 nanoscience & nanotechnology ,01 natural sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Ceramic membrane ,Flexural strength ,Phase (matter) ,0103 physical sciences ,Materials Chemistry ,Ceramics and Composites ,Composite material ,0210 nano-technology ,Porosity - Abstract
Porous SiC ceramic membrane supports are widely employed in a wide variety of high-temperature applications, such as hot flue gas filtration, porous burners and molten metal filters. Herein, SiC supports, with a porosity of ~37%, were prepared by using low-temperature bonding techniques and the influence of different bonding phases, such as mullite, cordierite and glass, on ambient-temperature flexural strength, hot modulus of rupture (HMOR), thermal shock resistance and oxidation resistance were systematically investigated. The results reveal that the glass-bonded SiC (GBSC) support exhibited the highest ambient-temperature flexural strength of 33.6 MPa, whereas the flexural strength of mullite-bonded SiC (MBSC) and cordierite-bonded SiC (CBSC) supports ranged from 22 to 25 MPa. However, the presence of glass phase deteriorated the high-temperature properties of the support. MBSC support rendered superior mechanical strength at high temperature and self-strengthening in a certain temperature range, such as HMOR improved 47.5% at 900 °C, but HMOR of glass-bonded support was only 57.4% of the ambient-temperature strength. Moreover, MBSC and CBSC supports exhibited better thermal shock resistance than GBSC supports and the critical temperature difference of water quenching for MBSC supports was ~200 °C higher than GBSC supports. In addition, MBSC support rendered superior oxidation resistance and exhibited a weight gain rate of ~0.1% at 1150 °C for 24 h, which is 54.4% and 42.2% lower than CBSC and GBSC supports, respectively.
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- 2020
29. Function and transcriptional regulation of CsKCS20 in the elongation of very-long-chain fatty acids and wax biosynthesis in Citrus sinensis flavedo
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Yang Wang, Xianpeng Yang, Zhaoxing Chen, Jin Zhang, Kai Si, Rangwei Xu, Yizhong He, Feng Zhu, and Yunjiang Cheng
- Subjects
Genetics ,food and beverages ,Plant Science ,Horticulture ,Biochemistry ,Biotechnology - Abstract
Cuticular wax on plant aerial surfaces plays a vital role in the defense against various stresses, and the genes related to wax metabolism have been well documented in several model plants. However, there is very limited research on the key enzymes and transcription factors (TFs) associated with carbon chain distribution and wax biosynthesis in citrus fruit. In this study, an analysis of wax metabolites indicated that even carbon-chain (C24-C28) metabolites are the dominant wax components in citrus fruit, and a 3-ketoacyl-CoA synthase (KCS) family gene (CsKCS20) plays an important role in the carbon chain distribution during wax biosynthesis in a wax-deficient mutant (MT). Expression of CsKCS20 in yeast indicated that CsKCS20 can catalyze the biosynthesis of C22 and C24 very-long-chain fatty acids (VLCFAs). In addition, transcriptome and sequence analysis indicated that the differential expression of CsKCS20 between the wild-type (WT) and MT fruit can be partly attributed to the regulation of CsMYB96, which was further confirmed by yeast one-hybrid (Y1H) assays, electrophoretic mobility shift assays (EMSAs) and dual luciferase assays. The functions of CsMYB96 and CsKCS20 in wax biosynthesis were further validated by heterologous expression in Arabidopsis. In summary, this study elucidates the important roles of CsKCS20 and CsMYB96 in regulating VLCFA elongation and cuticular wax biosynthesis, which provides new directions for the improvement of citrus fruit wax quality in genetic breeding programs.
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- 2022
30. Mechanism of activator and pore surface adsorption in aluminum-based flameless ration heaters: A molecular dynamics study
- Author
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Kai Si, Chongxin Liu, Jiajia Fang, Hang Yin, and Chunjiang Zhang
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General Physics and Astronomy ,Surfaces and Interfaces ,General Chemistry ,Condensed Matter Physics ,Surfaces, Coatings and Films - Published
- 2023
31. Analysis of monitoring effect on Hybrid Electric Field for AC/DC Cross Line
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Yi Yang, Xue-kai Si Ma, Shu-bo Fang, Qing Han, and Zan-dong Zhou
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History ,Computer Science Applications ,Education - Abstract
Electrostatic induction charge which generated by the coupling effect of hybrid electric field of AC/DC cross line and metal object under the transmission line can cause different levels of electric shock injury to human. In order to find out the distribution law of the hybrid electric field and reduce the effect of electrostatic induction, this paper set up shielding lines which paralleled to the AC and DC lines respectively on the outside of the side conductors and along the diagonal of parallelogram at crossing point, then measured the electric field distribution in shielding areas of 750kV AC and 500kV DC lines and the induced voltages of shielding lines in different states, analyzed the effect of shielding line on power frequency electric field and DC composite electric field. The results showed that shielding lines have a reducing effect on the hybrid electric field of the cross lines, the average power frequency field strength is reduced by 12.6%, the DC composite field and power frequency electric field at the crossing position was far less than the limits specified in the respective standards. Both induced voltage of bare lines and shielding lines wrapped with adhesive tape increase with the raise of erection height. Under the same conditions, the average induction voltage of bare conductor is 9.3% higher than that of shielding lines wrapped with adhesive tape. There is no obvious difference between parallel and vertical erection methods of the same number of shielding lines in the degree of reduction of induced voltage.
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- 2022
32. Optimization Strategies of Transcranial Magnetic Stimulation in Major Depressive Disorder.
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Kai-Si Wen and Wei Zheng
- Abstract
The article focuses on optimization strategies for trans cranial magnetic stimulation (TMS) in treating Major Depressive Disorder (MDD). It explores various TMS techniques, including high-frequency TMS, bilateral TMS, accelerated TMS, deep TMS, priming TMS and synchronized TMS, highlighting their efficacy in enhancing treatment outcomes for MDD.
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- 2023
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33. The role of Type III secretion system in the pathogenesis of Pseudomonas aeruginosa microbial keratitis
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Shen, ElizabethP, primary, Yang, JustinJ, additional, and Tsuei, Kai-Si Claire, additional
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- 2022
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34. Crack Propagation Process and Seismogenic Mechanisms of Rock Due to the Influence of Freezing and Thawing
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Leilei Zhao, Zhendong Cui, Kai Si, Yan Zhao, and Ruidong Peng
- Subjects
Technology ,Materials science ,QH301-705.5 ,QC1-999 ,Moment tensor ,Uniaxial compression ,Stress (mechanics) ,Rock engineering ,AE moment tensor ,Ultimate tensile strength ,General Materials Science ,Geotechnical engineering ,Biology (General) ,signal processing ,Instrumentation ,QD1-999 ,Fluid Flow and Transfer Processes ,Process Chemistry and Technology ,Physics ,General Engineering ,Fracture mechanics ,Engineering (General). Civil engineering (General) ,Computer Science Applications ,freeze–thaw damage ,fracture process ,Chemistry ,Acoustic emission ,Scientific method ,TA1-2040 ,acoustic emission - Abstract
A common problem in cold regions is the influence of freeze–thaw damage on the stability of rock engineering. Therefore, a series of uniaxial compression tests of sandstone after freeze–thaw treatment was carried out in this study. The purpose was to express the initial damage of rock after freezing and thawing treatment more quantitatively and to study the influence of freeze–thaw damage on the rock crack growth process to provide some reference for the stability evaluation of rock engineering in cold regions. The results showed that the number of freeze–thaw cycles and the lowest freeze–thaw temperature had a significant effect on the rock damage and characteristic stress value, and the number of cycles had a more obvious effect: with an increase in the number of freeze–thaw cycles and a decrease in the freeze–thaw temperature, the initial damage DNT had an increasing trend. In addition, the intrinsic mechanism of the freeze–thaw effect on the rock characteristic stress was explained from the perspective of a meso-mechanical mechanism. From the inversion results of the acoustic emission (AE) moment tensor, it was found that the proportion of tensile cracks gradually increased with the increase in the initial damage of the rock in the stable and unsteady stages of the rock crack propagation.
- Published
- 2021
35. A feasibility study on preoperative carbohydrate loading in older patients undergoing hip fracture surgery
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Kai Sing Yap, PS Loh, Yi Xian Foong, Chu Zhen Mok, Terence Ong, and Hui Min Khor
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Carbohydrate loading ,Hip fracture ,Elderly ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background Preoperative carbohydrate loading in Enhanced Recovery After Surgery is an independent predictor of postoperative outcomes. By reducing the impact of surgical stress response, fasting-induced insulin resistance is modulated. As a clear fluid, consuming carbohydrate drink is safe up to 2 h preoperatively. Widely practiced in abdominal surgeries, its implementation in hip fracture surgeries is yet to be recognized. This study aimed to identify the feasibility of preoperative carbohydrate loading in hip fracture surgery and assess its clinical effects. Methods This was a randomized controlled, open labelled trial. Patients ≥ 65 years old without diabetes mellitus, has hip fracture were recruited in a tertiary hospital between November 2020 and May 2021. The intervention was carbohydrate loading versus standard preoperative fasting. Results Thirty-four ASA I-III patients (carbohydrate loading and control, n = 17 each), mean age 78 years (SEM ± 1.5), mean body mass index 23.7 (SEM ± 0.6 kg/m2) were recruited. Analysis for feasibility of carbohydrate loading (n = 17) demonstrated attrition rate of 29% (n = 5). Otherwise, all recruited patients were compliant (100% compliance) with no adverse events reported. There was no significant difference among groups in the postoperative nausea and vomiting, pain score, fatigue level, muscle strength, postoperative infection and length of hospital stay assessed at 24–48 h postoperatively. Conclusion The implementation of preoperative carbohydrate loading was found to be feasible preoperatively in hip fracture surgeries but requires careful coordination among multidisciplinary teams. An adequately powered randomized controlled study is needed to examine the full benefits of preoperative carbohydrate loading in this group of patients. Trial registration This study was registered in ClinicalTrial.gov (ClinicalTrials.gov identifier: NCT04614181, date of registration: 03/11/2020).
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- 2024
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36. Vibrotactile enhancement of musical engagement
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Kai Siedenburg, Michel Bürgel, Elif Özgür, Christoph Scheicht, and Stephan Töpken
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Medicine ,Science - Abstract
Abstract Sound is sensed by the ear but can also be felt on the skin, by means of vibrotactile stimulation. Only little research has addressed perceptual implications of vibrotactile stimulation in the realm of music. Here, we studied which perceptual dimensions of music listening are affected by vibrotactile stimulation and whether the spatial segregation of vibrations improves vibrotactile stimulation. Forty-one listeners were presented with vibrotactile stimuli via a chair’s surfaces (left and right arm rests, back rest, seat) in addition to music presented over headphones. Vibrations for each surface were derived from individual tracks of the music (multi condition) or conjointly by a mono-rendering, in addition to incongruent and headphones-only conditions. Listeners evaluated unknown music from popular genres according to valence, arousal, groove, the feeling of being part of a live performance, the feeling of being part of the music, and liking. Results indicated that the multi- and mono vibration conditions robustly enhanced the nature of the musical experience compared to listening via headphones alone. Vibrotactile enhancement was strong in the latent dimension of ‘musical engagement’, encompassing the sense of being a part of the music, arousal, and groove. These findings highlight the potential of vibrotactile cues for creating intensive musical experiences.
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- 2024
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37. The role of Type III secretion system in the pathogenesis of
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Justin J, Yang, Kai-Si Claire, Tsuei, and Elizabeth P, Shen
- Published
- 2021
38. Design and Implementation of Online Marketing Management System for Small and Medium Enterprises
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Kai Si
- Subjects
System deployment ,Scientific management ,Business process ,Software deployment ,business.industry ,Computer science ,Management system ,Systems engineering ,Access control ,business ,Requirements analysis ,Desk - Abstract
According to the design standard of software engineering and scientific management theory, and the requirements of e-commerce, the business process of ERP management system is redesigned, to provide small and medium-sized enterprises with e-commerce ERP solutions that meet their own needs. The system adopts Struts + Spring + Hibernate and ExtJS 2.0 framework structure, which is conducive to the improvement of development efficiency. At the same time, the requirements analysis, outline design, detailed design, implementation, testing and deployment of the system are completed. The front desk is combined with Web2.0 technology, which is used for interface display and operation interaction. Finally, based on the key technologies used in the system, the implementation, testing and deployment of the system are introduced. The system deployment is successfully implemented, which verifies the stability of the design architecture and the rationality and effectiveness of the access control model.
- Published
- 2021
39. 5G Multimedia Precision Marketing Based on the Improved Multisensor Node Collaborative Filtering Recommendation Algorithm
- Author
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Kai Si, Min Zhou, and Yingfang Qiao
- Subjects
Article Subject ,Control and Systems Engineering ,T1-995 ,Electrical and Electronic Engineering ,Instrumentation ,Technology (General) - Abstract
The rapid development of web technology has brought new problems and challenges to the recommendation system: on the one hand, the traditional collaborative filtering recommendation algorithm has been difficult to meet the personalized recommendation needs of users; on the other hand, the massive data brought by web technology provides more useful information for recommendation algorithms. How to extract features from this information, alleviate sparsity and dynamic timeliness, and effectively improve recommendation quality is a hot issue in the research of recommendation system algorithms. In view of the lack of an effective multisource information fusion mechanism in the existing research, an improved 5G multimedia precision marketing based on an improved multisensor node collaborative filtering recommendation algorithm is proposed. By expanding the input vector field, the features of users’ social relations and comment information are extracted and fused, and the problem of collaborative modelling of these two kinds of important auxiliary information is solved. The objective function is improved, the social regularization term and the internal regularization term in the vector domain are analysed and added from the perspective of practical significance and vector structure, which alleviates the overfitting problem. Experiments on a large number of real datasets show that the proposed method has higher recommendation quality than the classical and mainstream baseline algorithm.
- Published
- 2021
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40. Comparative Study on Mineral-Scale Microcrack Propagation of Shale under Different Loading Methods
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Weige Han, Zhendong Cui, Kai Si, Yan Zhao, and Zhang Jianyong
- Subjects
Mineral ,Article Subject ,Scale (ratio) ,0211 other engineering and technologies ,Fracture mechanics ,02 engineering and technology ,010502 geochemistry & geophysics ,Engineering (General). Civil engineering (General) ,01 natural sciences ,Cohesive zone model ,Ultimate tensile strength ,Echelon formation ,Geotechnical engineering ,Boundary value problem ,TA1-2040 ,Oil shale ,Geology ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Civil and Structural Engineering - Abstract
Producing a sufficient volume of multiscale crack networks is key to enhancing recovery of shale gas. The formation of crack network largely depends on initiation and propagation of microcracks. To reveal the influence of different loading methods on the propagation of mineral-scale microcracks, this study used the Voronoi tessellation technique to establish a cohesive zone model of shale mineral distribution and applied six different boundary conditions to represent different loading methods. Crack path characteristics, rupture characteristics, continuous crack propagation and turning, and en echelon intermittent crack propagation under different loading methods were compared and analyzed. The essence of different loading methods affecting the length and complexity of cracks was the spreading range of tensile microcracks. The mechanical properties of minerals led to dissimilarities in continuous crack propagation and turning. The formation and propagation of en echelon intermittent fractures of different scales were mainly impacted by the heterogeneity of minerals and mineral aggregates. The spreading direction and connection form of en echelon intermittent fractures were mainly affected by the loading method. Conclusions arising from mineral-scale simulations contribute to understanding the mechanism of microcrack propagation resulting from different loading methods, and these conclusions have a guiding significance to enhanced shale gas recovery.
- Published
- 2021
41. A Testbench for Measuring the Dynamic Force-Displacement Characteristics of Shockmounts
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Bernhard Heinemann, Kai Simanowski, Michael Clasen, Jan Dreesen, and Delf Sachau
- Subjects
shock isolator ,wire rope shockmount ,elastomer shockmount ,dynamic force-displacement characteristics ,Physics ,QC1-999 - Abstract
Shockmounts in naval applications are used to mount technical equipment onto the structure of naval vessels. The insulating effect against mechanical shock is important here, as it can excite the structure in the event of underwater explosions and otherwise cause damage to the equipment. Although knowledge of the dynamic properties of shockmounts is important to naval architects, the dynamic force-displacement characteristics of shockmounts are often tested and measured statically and/or in the harmonic field. Recently, an inertia-based method and a dynamic model for measuring the dynamic force-displacement characteristics of shockmounts was described. This paper presents a full description of a testbench for implementing this method. The testbench incorporates a drop table for excitation. The proposed setup can be configured for measuring the dynamic characteristics of elastomer and wire rope shockmounts, with shock loads in compression, tension, shear and roll directions. The advanced Kelvin–Voigt model for shockmounts is applied, showing that the dynamic force-displacement characteristics measured with this setup are qualified to generate model parameters for further use.
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- 2023
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42. Ultra-high-performance liquid chromatograph with triple-quadrupole mass spectrometer quantitation of twelve phenolic components in different parts of sarcandra glabra
- Author
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Zhang, Wei, primary, Jiang, Zhi-Hong, primary, Lu, Jing-Guang, additional, Wang, Cai-Yun, additional, Chen, Da-Xin, additional, Wang, Jing-Rong, additional, Che, Kai-Si, additional, and Zhong, Ming, additional
- Published
- 2021
- Full Text
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43. Multi-omics subgroups associated with glycaemic deterioration in type 2 diabetes: an IMI-RHAPSODY Study
- Author
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Shiying Li, Iulian Dragan, Van Du T. Tran, Chun Ho Fung, Dmitry Kuznetsov, Michael K. Hansen, Joline W. J. Beulens, Leen M. ‘t Hart, Roderick C. Slieker, Louise A. Donnelly, Mathias J. Gerl, Christian Klose, Florence Mehl, Kai Simons, Petra J. M. Elders, Ewan R. Pearson, Guy A. Rutter, and Mark Ibberson
- Subjects
multi-omics ,type 2 diabetes ,glycaemic deterioration ,metabolic syndrome ,lipidomics ,proteomics ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
IntroductionType 2 diabetes (T2D) onset, progression and outcomes differ substantially between individuals. Multi-omics analyses may allow a deeper understanding of these differences and ultimately facilitate personalised treatments. Here, in an unsupervised “bottom-up” approach, we attempt to group T2D patients based solely on -omics data generated from plasma.MethodsCirculating plasma lipidomic and proteomic data from two independent clinical cohorts, Hoorn Diabetes Care System (DCS) and Genetics of Diabetes Audit and Research in Tayside Scotland (GoDARTS), were analysed using Similarity Network Fusion. The resulting patient network was analysed with Logistic and Cox regression modelling to explore relationships between plasma -omic profiles and clinical characteristics.ResultsFrom a total of 1,134 subjects in the two cohorts, levels of 180 circulating plasma lipids and 1195 proteins were used to separate patients into two subgroups. These differed in terms of glycaemic deterioration (Hazard Ratio=0.56;0.73), insulin sensitivity and secretion (C-peptide, p=3.7e-11;2.5e-06, DCS and GoDARTS, respectively; Homeostatic model assessment 2 (HOMA2)-B; -IR; -S, p=0.0008;4.2e-11;1.1e-09, only in DCS). The main molecular signatures separating the two groups included triacylglycerols, sphingomyelin, testican-1 and interleukin 18 receptor.ConclusionsUsing an unsupervised network-based fusion method on plasma lipidomics and proteomics data from two independent cohorts, we were able to identify two subgroups of T2D patients differing in terms of disease severity. The molecular signatures identified within these subgroups provide insights into disease mechanisms and possibly new prognostic markers for T2D.
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- 2024
- Full Text
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44. Computed tomography-based thermography (CTT) in microwave ablation: prediction of the heat ablation zone in the porcine liver
- Author
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Bogdan Kostyrko, Kerstin Rubarth, Christian Althoff, Franz Gerd Martin Poch, Christina Ann Neizert, Miriam Zibell, Bernhard Gebauer, Kai Siegfried Lehmann, Stefan Markus Niehues, Jürgen Mews, Torsten Diekhoff, and Julian Pohlan
- Subjects
Computed tomography ,Microwave ablation ,Ablation zone prediction ,In vivo experiment ,Computed tomography thermography ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Abstract Objectives The aim of the study was to investigate computed tomography-based thermography (CTT) for ablation zone prediction in microwave ablation (MWA). Methods CTT was investigated during MWA in an in vivo porcine liver. For CTT, serial volume scans were acquired every 30 s during ablations and every 60 s immediately after MWA. After the procedure, contrast-enhanced computed tomography (CECT) was performed. After euthanasia, the liver was removed for sampling and further examination. Color-coded CTT maps were created for visualization of ablation zones, which were compared with both CECT and macroscopy. Average CT attenuation values in Hounsfield units (HU) were statistically correlated with temperatures using Spearman’s correlation coefficient. CTT was retrospectively evaluated in one patient who underwent radiofrequency ablation (RFA) treatment of renal cell carcinoma. Results A significant correlation between HU and temperature was found with r = − 0.77 (95% confidence interval (CI), − 0.89 to − 0.57) and p
- Published
- 2023
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45. Genome-wide association analysis of plasma lipidome identifies 495 genetic associations
- Author
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Linda Ottensmann, Rubina Tabassum, Sanni E. Ruotsalainen, Mathias J. Gerl, Christian Klose, Elisabeth Widén, FinnGen, Kai Simons, Samuli Ripatti, and Matti Pirinen
- Subjects
Science - Abstract
Abstract The human plasma lipidome captures risk for cardiometabolic diseases. To discover new lipid-associated variants and understand the link between lipid species and cardiometabolic disorders, we perform univariate and multivariate genome-wide analyses of 179 lipid species in 7174 Finnish individuals. We fine-map the associated loci, prioritize genes, and examine their disease links in 377,277 FinnGen participants. We identify 495 genome-trait associations in 56 genetic loci including 8 novel loci, with a considerable boost provided by the multivariate analysis. For 26 loci, fine-mapping identifies variants with a high causal probability, including 14 coding variants indicating likely causal genes. A phenome-wide analysis across 953 disease endpoints reveals disease associations for 40 lipid loci. For 11 coronary artery disease risk variants, we detect strong associations with lipid species. Our study demonstrates the power of multivariate genetic analysis in correlated lipidomics data and reveals genetic links between diseases and lipid species beyond the standard lipids.
- Published
- 2023
- Full Text
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46. The role of Type III secretion system in the pathogenesis of Pseudomonas aeruginosa microbial keratitis.
- Author
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Yang, Justin, Tsuei, Kai-Si Claire, and Shen, Elizabeth
- Abstract
Pseudomonas aeruginosa is the most commonly isolated Gram-negative pathogen causing sight-threatening microbial keratitis (MK). Contact lens wear is the most significant risk factor associated with pseudomonal MK. Understanding the pathogenesis of MK due to P. aeruginosa and its interactions with contact lenses is crucial in preventing these often rapidly progressive and highly antibiotic-resistant infections. Bacterial virulence factor Type III secretion system (T3SS) has significant interplays between contact lens material, antibiotic sensitivity, disinfectant selectivity, and bacterial cell invasion. Depending on the T3SS exotoxins produced, P. aeruginosa strains are divided into cytotoxic or invasive strains. Cytotoxic strains are relatively resistant to commercial disinfectants, while invasive strains are more antibiotic resistant. Therefore, contact lens wearers are more predisposed to cytotoxic P. aeruginosa infections, and patients with trauma or previous surgery are more prone to infection by invasive strains. Previous studies with mutant P. aeruginosa strains unable to produce T3SS exotoxins were more susceptible to disinfectants and less able to adhere to soft contact lenses, indicating an essential role of T3SS in bacterial virulence. Invasion of P. aeruginosa intracellularly was found to be associated with control of scaffold protein IQ-domain GTPase-activating protein 1 (IQGAP1) and human corneal epithelial cell tight junctions. Knockdown of IQGAP1 strengthened tight junctions that prevented intracellular survival of invasive P. aeruginosa strains and enhanced corneal epithelial cell survival. These novel findings of the vital role of T3SS in the pathogenesis of pseudomonal MKs will provide new guidelines in both prevention and treatment of this common eye-blinding infection. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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47. Should Empiric Anti-Fungals Be Administered Routinely for All Patients with Perforated Peptic Ulcers? A Critical Review of the Existing Literature
- Author
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Kai Siang Chan, Lee Yee Calista Tan, Sunder Balasubramaniam, and Vishal G. Shelat
- Subjects
anti-fungal ,culture ,intra-abdominal sepsis ,microbiology ,peptic ulcer perforation ,Medicine - Abstract
A perforated peptic ulcer (PPU) is a surgical emergency with a high mortality rate. PPUs cause secondary peritonitis due to bacterial and fungal peritoneal contamination. Surgery is the main treatment modality and patient’s comorbidites impacts perioperative morbidity and surgical outcomes. Even after surgery, resuscitation efforts should continue. While empiric antibiotics are recommended, the role of empiric anti-fungal treatment is unclear due to a lack of scientific evidence. This literature review demonstrated a paucity of studies evaluating the role of empiric anti-fungals in PPUs, and with conflicting results. Studies were heterogeneous in terms of patient demographics and underlying surgical pathology (PPUs vs. any gastrointestinal perforation), type of anti-fungal agent, timing of administration and duration of use. Other considerations include the need to differentiate between fungal colonization vs. invasive fungal infection. Despite positive fungal isolates from fluid culture, it is important for clinical judgement to identify the right group of patients for anti-fungal administration. Biochemistry investigations including new fungal biomarkers may help to guide management. Multidisciplinary discussions may help in decision making for this conundrum. Moving forward, further research may be conducted to select the right group of patients who may benefit from empiric anti-fungal use.
- Published
- 2024
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48. Ultra-high-performance liquid chromatograph with triple-quadrupole mass spectrometer quantitation of twelve phenolic components in different parts of sarcandra glabra
- Author
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Ming Zhong, Jing-Rong Wang, Kai-Si Che, Da-Xin Chen, Cai-Yun Wang, Jing-Guang Lu, Wei Zhang, and Zhi-Hong Jiang
- Subjects
chemistry.chemical_compound ,Chromatography ,Complementary and alternative medicine ,chemistry ,Relative standard deviation ,Flavanonol ,Ultra high performance ,Mass spectrometry ,Mass spectrometric ,Triple quadrupole mass spectrometer ,Sarcandra glabra - Abstract
Objective: The study objective was to determine phenolic components for the quality control (QC) of cultivated Sarcandra glabra (Thunb.) Makino ( S. glabra). Materials and Methods: A sensitive, ultra-high-performance liquid chromatography-tandem mass spectrometric method for the simultaneous determination of 12 phenolic components has been developed. Six caffeoylquinic acids, two caffeoylshikimic acids, and four flavanonol glucosides were selected for the comprehensive analysis of distribution in different parts (root, stem, and leaf). Results: Twelve phenolic components were linear in the concentration range of 0.005–5.0 μg/mL ( R2 > 0.995). The relative standard deviation of intra-day and inter-day precision across three validation runs over the entire concentration range was
- Published
- 2021
49. Determinants of quality of life in adults with epilepsy: a multicenter, cross-sectional study from Germany
- Author
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Kai Siebenbrodt, Laurent M. Willems, Felix von Podewils, Peter Michael Mross, Michael Strüber, Lisa Langenbruch, Laura Bierhansl, Iris Gorny, Juliane Schulz, Bernadette Gaida, Nadine Conradi, Annika Süß, Felix Rosenow, and Adam Strzelczyk
- Subjects
Epilepsy ,Depression ,Quality of life ,Seizure ,QOLIE-31 ,Anti-seizure medication ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background Assessment of quality of life (QoL) has become an important indicator for chronic neurological diseases. While these conditions often limit personal independence and autonomy, they are also associated with treatment-related problems and reduced life expectancy. Epilepsy has a tremendous impact on the QoL of patients and their families, which is often underestimated by practitioners. The aim of this work was to identify relevant factors affecting QoL in adults with epilepsy. Methods This cross-sectional, multicenter study was conducted at four specialized epilepsy centers in Germany. Patients diagnosed with epilepsy completed a standardized questionnaire focusing on QoL and aspects of healthcare in epilepsy. Univariate regression analyses and pairwise comparisons were performed to identify variables of decreased QoL represented by the overall Quality of Life in Epilepsy Inventory (QOLIE-31) score. The variables were then considered in a multivariate regression analysis after multicollinearity analysis. Results Complete datasets for the QOLIE-31 were available for 476 patients (279 [58.6%] female, 197 [41.4%] male, mean age 40.3 years [range 18–83 years]). Multivariate regression analysis revealed significant associations between low QoL and a high score on the Liverpool Adverse Events Profile (LAEP; beta=-0.28, p
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- 2023
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50. Identification of biomarkers for glycaemic deterioration in type 2 diabetes
- Author
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Roderick C. Slieker, Louise A. Donnelly, Elina Akalestou, Livia Lopez-Noriega, Rana Melhem, Ayşim Güneş, Frederic Abou Azar, Alexander Efanov, Eleni Georgiadou, Hermine Muniangi-Muhitu, Mahsa Sheikh, Giuseppe N. Giordano, Mikael Åkerlund, Emma Ahlqvist, Ashfaq Ali, Karina Banasik, Søren Brunak, Marko Barovic, Gerard A. Bouland, Frédéric Burdet, Mickaël Canouil, Iulian Dragan, Petra J. M. Elders, Celine Fernandez, Andreas Festa, Hugo Fitipaldi, Phillippe Froguel, Valborg Gudmundsdottir, Vilmundur Gudnason, Mathias J. Gerl, Amber A. van der Heijden, Lori L. Jennings, Michael K. Hansen, Min Kim, Isabelle Leclerc, Christian Klose, Dmitry Kuznetsov, Dina Mansour Aly, Florence Mehl, Diana Marek, Olle Melander, Anne Niknejad, Filip Ottosson, Imre Pavo, Kevin Duffin, Samreen K. Syed, Janice L. Shaw, Over Cabrera, Timothy J. Pullen, Kai Simons, Michele Solimena, Tommi Suvitaival, Asger Wretlind, Peter Rossing, Valeriya Lyssenko, Cristina Legido Quigley, Leif Groop, Bernard Thorens, Paul W. Franks, Gareth E. Lim, Jennifer Estall, Mark Ibberson, Joline W. J. Beulens, Leen M ’t Hart, Ewan R. Pearson, and Guy A. Rutter
- Subjects
Science - Abstract
Abstract We identify biomarkers for disease progression in three type 2 diabetes cohorts encompassing 2,973 individuals across three molecular classes, metabolites, lipids and proteins. Homocitrulline, isoleucine and 2-aminoadipic acid, eight triacylglycerol species, and lowered sphingomyelin 42:2;2 levels are predictive of faster progression towards insulin requirement. Of ~1,300 proteins examined in two cohorts, levels of GDF15/MIC-1, IL-18Ra, CRELD1, NogoR, FAS, and ENPP7 are associated with faster progression, whilst SMAC/DIABLO, SPOCK1 and HEMK2 predict lower progression rates. In an external replication, proteins and lipids are associated with diabetes incidence and prevalence. NogoR/RTN4R injection improved glucose tolerance in high fat-fed male mice but impaired it in male db/db mice. High NogoR levels led to islet cell apoptosis, and IL-18R antagonised inflammatory IL-18 signalling towards nuclear factor kappa-B in vitro. This comprehensive, multi-disciplinary approach thus identifies biomarkers with potential prognostic utility, provides evidence for possible disease mechanisms, and identifies potential therapeutic avenues to slow diabetes progression.
- Published
- 2023
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