bluuebunny/crossref_metadata_2025 huggingface dataset:
Mathematical Models for Physicochemical Properties of Different Amine-based Solvents in Post combustion CO2 Capture
Authors: Karunarathne Sumudu , Larsen Jeanette , Øi Lars Erik
Published: October 2022

In order to reduce global CO2 emissions, CO2 capture based on absorption in an amine/water mixture is an established method. To develop such processes, correct physicochemical properties like densities and viscosities are important.The first objective of this work is to explore mathematical correlations for fitting viscosity data for aqueous Monoethanolamine (MEA) and Methyldiethanolamine (MDEA). A second objective is to evaluate the prediction of viscosity based on parameters independent of viscosity measurements.13 developed correlations have been evaluated by comparing the maximum deviation of fitted models to the measured property, and by determining the average absolute relative deviation (AARD%). Python 3.6, MATLAB R2020b and Excel were used as the tools for regression.The results indicated that viscosity for aqueous amines was better correlated by Eyring’s viscosity model based on NRTL (Non-Random-Two Liquid model) rather than a Redlich-Kister correlation. The achieved AARD% of aqueous MEA were 2.39 for Redlich-Kister, 1.87 for Eyring-NRTL and 1.88 for the segment-based Eyring-NRTL model. The same trend was achieved for aqueous MDEA with AARD% of 3.04, 2.23 and 1.88 for different approaches.The possibility of using data from vapor/liquid equilibrium parameters to predict viscosity in MEA/water and MDEA/water was evaluated. Using parameters in the equilibrium model NRTL from the simulation program Aspen HYSYS in a model from Karunarathne indicated that it is possible to predict viscosity reasonably well without experimental viscosity data.
Data-driven approaches for modelling of sub-critical coal-fired boiler
Authors: Formont Valentin , Skjervold Vidar T. , Nord Lars O.
Published: October 2022

Due to increasing shares of renewable electricity sources in the grid, thermal power plants need to operate in a more flexible manner in the future. This will involve more frequent startups, shutdowns, and load changes. A central part of a thermal power plant analysed in this study is the coal-fired boiler. In a previous study, a first-principle model of a sub-critical coalfired boiler has been developed and validated with operational data from a Polish power plant. Based on this model, this work aims to develop a computationally efficient and sufficiently accurate data-driven model that is easy to implement in new software. A selection of multi-output algorithms was first compared using nonoptimised parameters, with very few adaptations to the data set. Then, each algorithm had undergone three different optimisation routines to tune the hyper-parameters. The results of the nonoptimised models were compared with the optimised ones, and then compared to the reference first-principle model using the average Mean Absolute Percentage Error as a score. The methods used comprise six base learners and three algorithms using ensemble methods. The optimisation routines were based on the Powell conjugate direction method, Bayesian optimisation and evolutionary algorithm. All the data-driven models had shown a lower percentage error than the first principle model, and optimisation had resulted in improved prediction capacity for every base learner, but not for ensemble method-based algorithms.
Numerical modelling of fin side heat transfer and pressure loss for compact heat recovery steam generators
Authors: Espelund Johan R. , Meyer Ole H. H. , Skaugen Geir
Published: October 2022

An optimization tool for offshore bottoming cycle and heat recovery steam generator (HRSG) design has previously been developed. The tool is based on empirical correlations to obtain hydraulic and thermal quantities for the HRSG. However, as these correlations are based on experiments with typical onshore designs, they may not be valid for the compact designs encountered in offshore HRSGs.In order to extend the validity range of the optimization tool, this work presents a numerical model able to predict heat transfer and pressure loss in finned tube bundles by means of Computational Fluid Dynamics (CFD), utilizing a periodic domain to reduce computational costs. Both steady-state and transient models were applied, using the Spalart-Allmaras turbulence model, and their performance compared. To validate the model, results were compared with available experimental data, and then the model’s performance was compared with a selected empirical correlation.Three different fin-tube geometries were investigated (two serrated and solid) with varying tube layout angles. A parameterized grid generation tool was developed and used to generate grids for the selected geometries. The CFD results were found to be within 20 % of the experimental data, and were in most cases more accurate than the empirical correlation. The steady-state simulations did, however, not converge for the geometry with the largest layout angle. The steady-state framework should therefore be applied only to compact tube layouts. The transient simulations, though being computationally more intensive, are also able to model large layout angles.
Modeling and analysis of secondary oil recovery with water flooding from a heterogeneous reservoir through advanced wells.
Authors: Bhujange Onkar , Moradi Ali , Kumara Amaranath , Moldestad Britt
Published: October 2022

Oil and gas will remain the most important source of energy for the foreseeable future according to DNV’s Energy Transition Outlook 2021, and there is an urgent need to improve oil and gas recovery with less carbon footprint to meet the future energy demands. For the extraction of oil from the reservoir, horizontal drilling is being applied due to its higher recovery rate. These horizontal wells are advanced wells equipped with downhole Flow Control Devices (FCDs), sand screens, zonal isolation as well as monitoring and control systems, etc. FCDs are the key elements of advanced wells. The main objective of this paper is to modelling and simulation of secondary oil recovery with water flooding from a heterogeneous reservoir through advanced wells completed by main types of FCDs. In this paper, a computational study of oil recovery from a black oil reservoir is performed through modelling and simulation using the Petrel© software. The modified ‘Egg Model’ is used which is a synthetic heterogeneous reservoir model consisting of an ensemble of relatively small three-dimensional realizations of a channelized oil reservoir produced under water flooding conditions. A comparative analysis of reservoir models with vertical open hole wells and horizontal open hole wells is presented where it is found that the horizontal well produces 23% more oil. Also, horizontal open-hole wells are further equipped with ICDs which have reduced the water production by 91.4% and have also delayed the water breakthrough in comparison to open-hole horizontal wells.
Influence on the fluidization pattern of a freely bubbling fluidized bed with different modes of air supply
Authors: Jaiswal Rajan , Eikeland Marianne S. , Moldestad Britt M. E. , Thapa Rajan K.
Published: October 2022

Bubbling fluidized bed (BFB) reactors are extensively used in several process applications like gasification, pyrolysis, drying, and combustions due to their excellent mixing properties and good temperature control. The bubble dynamic and particle movement in the reactor is primarily responsible for uniform heat and mass transfer and mixing. The properties of bubbles in BFB are governed by the gas distribution inside the reactor or supply of the fluidizing gas. This work investigates the influence on the fluid dynamic behaviour of the BFB reactor at different fluidizing gas injection systems using the Computational Particle Fluid dynamic model. Three different modes of fluidizing gas injection include uniform injection, air injection via twenty-five nozzles, and air supply via side nozzles along the reactor height in a gasification reactor of 10.04 cm diameter. Air is used as the fluidizing gas and silica sand as the bed material. The CPFD model is developed in Barracuda Virtual reactor 20.01. The CPFD model is validated against the experimental data obtained from the Electrical Capacitance Tomography (ECT) sensors. The result depicts the better fluidization quality of the bed with uniform air supply as flow boundary and air injection via twenty-five nozzles located at the bottom of the reactor. With air injection via two side nozzles along the reactor height, the bed is fluidized with large bubbles and particle entrainment in the freeboard zone of the reactor. A method is proposed to improve the fluidization quality of the bed while using side nozzles as inlet flow Boundary Conditions (BC) for air injection. The proposed method includes addition of four nozzles along the reactor wall instead of two which improves the fluidization quality of the bed in terms of smaller size bubbles without particle entrainment in the freeboard region.
Study of gasification behavior for a biorefinery lignin waste in a fluidized bed gasification reactor
Authors: Ghosh Saugata , Timsina Ramesh , Moldestad Britt
Published: October 2022

Lignocellulosic biorefineries, paper and pulp industries across the globe can convert cellulose and hemicellulose parts of the biomass into higher valued products. However, lignin from biomass is an underutilized biorefinery waste. Value-added applications of lignin waste should be investigated to produce low-molecular-weight compounds as an alternative to petrochemical compounds. Valorization and lignin recovery play an important role in ‘green shifts’ for such industries. In this work, the authors performed gasification of lignin pellets obtained from one biorefinery located in Finland. A 20-kW pilot-scale bubbling fluidized bed gasifier was used for the experiments. A computational particle fluid dynamics model based on a multi-phase particle in cell approach was developed for the same process. The developed model was validated against the experimental results.The experimental results showed good conversion of lignin pellets into permanent light gases such as carbon monoxide, hydrogen, methane, etc. The average production of product gas and the lower heating value were 5.74 Nm³/hr and 4.95 MJ/Nm³, respectively. The average molar gas compositions obtained from the experimental study were 0.04 for CH₄, 0.16 for CO, 0.15 for CO₂, 0.13 for H₂ and 0.51 for N₂.
Integrating energy in the conceptual design stage to optimize building form
Authors: Vafaee Niloofar Zaker , Sandani Melika , Khameneh Tahmineh Akbarinejad , Tagnocchetti Matteo , Izumi Bunji , Finocchiaro Luca
Published: October 2022

In architecture, Integrated Energy Design (IED) entails considering energy during each design phase, especially in the early design stage. The form of a building is an important factor in this stage due to its considerable impact on energy consumption. Finding the optimal form is a time-consuming process, and computational design techniques can help designers to facilitate this process and achieve a design solution with acceptable performance in terms of CO2 emission. Moreover, the surrounding buildings, trees and urban elements can affect the energy and daylight of the project by casting shadows. Considering all these elements throughout the design process can be very demanding and take several working days. Today, digital tools make it possible to parametrically analyze morphological characteristics of buildings to identify the most efficient solution. The present study proposes an environmental-simulation based design workflow to be used in the early design stage to determine the building’s form parameters (height, angle,..) in a given urban area based on the weather data and the surrounding context. This process is done by parametric design tools and environmental simulations in Rhino3D®, Grasshopper®, and ladybug Tools®. The typical Norwegian cabin’s form parameters are applied in the visual coding program (Grasshopper®) to generate the initial geometry for optimization. Due to the great effect of the energy consumption on the CO2 emission, minimizing energy, maximizing thermal comfort and the sky view percentage were the main objectives. To test the workflow the weather data of Tromsø (Norway) and 3d model of the surrounding context of a design location was applied as inputs. The output of this application was several building’s form alternatives for that specific location. This study showed using the digital tools and parametric design thinking can help the designers to apply the climatic data in the design process to narrow down the design solutions.
Aspen Hysys simulation of the methanol synthesis based on gas from biomass gasification
Authors: Fossen Morten A. , Halvorsrød Johann , Narvestad Thomas , Tjemsland Sander , Timsina Ramesh , Eikeland Marianne S.
Published: October 2022

From the gasification of biomass, the produced gas mainly consists of CO, H2, CO2, and CH4. After gas cleaning and conditioning, the syngas obtained can be used to produce methanol, dimethyl ether, polymers, biofuels, etc. Methanol is one of the important industrial chemicals that can be used directly as a fuel or can be blended into conventional fuels. Methanol produced from renewable biomass sources can limit greenhouse gas emissions. Based on data on gas composition from experiments and simulations of the fluidized bed gasification reactor at the University of South-Eastern Norway, the methanol process is simulated with Aspen Hysys. It is desirable to assess how different process parameters affect the yield of methanol production. A Gibbs reactor was modeled with three gas-phase exothermic reactions. The product from the reactor is depressurized to separate gas from the liquid. The liquid enters the distillation column to give CH3OH in the distillate and the water as the bottom product. The yield of methanol is evaluated with regard to pressure, temperature, and H2/CO ratio. The theoretical H2/CO ratio for the methanol synthesis should be approximately between 1,5-2. However, different gas compositions were obtained from different types of fluidizing agents in the gasification reactor, and a low ratio of H2/CO gives a low yield of methanol. Fluidized bed gasification with steam as gasifying agent is preferable to increase the H2/CO ratio and give a higher methanol yield.
Composite fuzzy learning finite-time prescribed performance control of uncertain nonlinear systems with dead-zone inputs
Authors: Zhu Fang , Li Pengtong
Published: October 2022

This paper presents a composite fuzzy learning finite-time prescribed performance control (PPC) approach for uncertain nonlinear systems with dead-zone inputs. First, a finite-time performance function is constructed by a quartic polynomial. Subsequently, with the help of an error transformation function, the restriction problem of the tracking error performance is transformed into a stability problem of an equivalent transformation system. In order to ensure that all signals of the closed-loop system are bounded, a finite-time PPC method combined with fuzzy logic systems (FLSs) is proposed. Although the tracking error can be guaranteed to be limited within a predefined range, the proposed finite-time PPC method only uses instantaneous data, which cannot guarantee the accurate estimation of unknown functions under the influence of dead-zone inputs. Therefore, based on the persistent excitation (PE) condition, a predictive error is defined by using online recorded data and instantaneous data, and a corresponding composite learning finite-time PPC method with parameter updating the law, which can not only achieve the control aim of the former method but also improve the control effect, is designed. The simulation results verified that the composite learning finite-time PPC method is more effective than the finite-time PPC method without learning.
Biomechanical comparison of the undercut thread design versus conventional buttress thread for the lag screw of the dynamic hip screw system
Authors: Liu Fei , Feng Xiaoreng , Zheng Jianxiong , Leung Frankie , Chen Bin
Published: October 2022

Objective: To compare the fixation stability of the lag screw with a undercut thread design for the dynamic hip screw (DHS) system versus the lag screw with the conventional buttress thread.

Methods: The lag screws with the undercut thread (a flat crest feature, a tip-facing undercut feature) and buttress thread were both manufactured. Fixation stability was investigated using cyclic compressive biomechanical testing on custom osteoporotic femoral head sawbone. The forces required for the same vertical displacement in the two types of lag screw were collected to evaluate the resistance to migration. Varus angle was measured on X-ray images to assess the ability in preventing varus collapse. Finite element analysis (FEA) was performed to analyze the stress and strain distribution at the bone-screw interface of the two types of lag screws.

Results: The biomechanical test demonstrated that the force required to achieve the same vertical displacement of the lag screw with the undercut thread was significantly larger than the lag screw with conventional buttress thread (p < 0.05). The average varus angles generated by the undercut and buttress threads were 3.38 ± 0.51° and 5.76 ± 0.38°, respectively (p < 0.05). The FEA revealed that the region of high-stress concentration in the bone surrounding the undercut thread was smaller than that surrounding the buttress thread.

Conclusion: The proposed DHS system lag screw with the undercut thread had higher migration resistance and superior fixation stability than the lag screw with the conventional buttress thread.
An overview of PAX1: Expression, function and regulation in development and diseases
Authors: Wu Weiyin , Kong Xiangjun , Jia Yanhan , Jia Yihui , Ou Weimei , Dai Cuilian , Li Gang , Gao Rui
Published: October 2022

Transcription factors play multifaceted roles in embryonic development and diseases. PAX1, a paired-box transcription factor, has been elucidated to play key roles in multiple tissues during embryonic development by extensive studies. Recently, an emerging role of PAX1 in cancers was clarified. Herein, we summarize the expression and functions of PAX1 in skeletal system and thymus development, as well as cancer biology and outline its cellular and molecular modes of action and the association of PAX1 mutation or dysregulation with human diseases, thus providing insights for the molecular basis of congenital diseases and cancers.
B cell lymphoma 6A regulates immune development and function in zebrafish
Authors: Almohaisen Farooq L. J. , Heidary Somayyeh , Sobah Mohamed L. , Ward Alister C. , Liongue Clifford
Published: October 2022

BCL6A is a transcriptional repressor implicated in the development and survival of B and T lymphoctyes, which is also highly expressed in many non-Hodgkin’s lymphomas, such as diffuse large B cell lymphoma and follicular lymphoma. Roles in other cell types, including macrophages and non-hematopoietic cells, have also been suggested but require further investigation. This study sought to identify and characterize zebrafish BCL6A and investigate its role in immune cell development and function, with a focus on early macrophages. Bioinformatics analysis identified a homologue for BCL6A (bcl6aa), as well as an additional fish-specific duplicate (bcl6ab) and a homologue for the closely-related BCL6B (bcl6b). The human BCL6A and zebrafish Bcl6aa proteins were highly conserved across the constituent BTB/POZ, PEST and zinc finger domains. Expression of bcl6aa during early zebrafish embryogenesis was observed in the lateral plate mesoderm, a site of early myeloid cell development, with later expression seen in the brain, eye and thymus. Homozygous bcl6aa mutants developed normally until around 14 days post fertilization (dpf), after which their subsequent growth and maturation was severely impacted along with their relative survival, with heterozygous bcl6aa mutants showing an intermediate phenotype. Analysis of immune cell development revealed significantly decreased lymphoid and macrophage cells in both homozygous and heterozygous bcl6aa mutants, being exacerbated in homozygous mutants. In contrast, the number of neutrophils was unaffected. Only the homozygous bcl6aa mutants showed decreased macrophage mobility in response to wounding and reduced ability to contain bacterial infection. Collectively, this suggests strong conservation of BCL6A across evolution, including a role in macrophage biology.
2’-Fucosyllactose inhibits proliferation of Clostridioides difficile ATCC 43599 in the CDi-screen, an in vitro model simulating Clostridioides difficile infection
Authors: Wiese Maria , Schuren Frank H. J. , Smits Wiep Klaas , Kuijper Ed J. , Ouwens Anita , Heerikhuisen Margreet , Vigsnaes Louise , van den Broek Tim J. , de Boer Paulo , Montijn Roy C. , van der Vossen Jos M. B. M.
Published: October 2022

Background

Clostridioides difficile is a Gram-positive anaerobic bacterium that can produce the toxins TcdA and/or TcdB and is considered an opportunistic pathogen. C. difficile is mainly transmitted as endospores, which germinate to produce the pathogenic vegetative cells under suitable conditions in the gut. To efficiently screen novel therapeutic- interventions against the proliferation of C. difficile within a complex microbial community, platforms are needed that facilitate parallel experimentation. In order to allow for screening of novel interventions a medium-to-high throughput in vitro system is desirable. To this end, we have developed the 96-well CDi-screen platform that employs an adapted simulated ileal effluent medium (CDi-SIEM) and allows for culturing of pathogenic C. difficile.

Methods

C. difficile strain ATCC 43599 was inoculated in the form of vegetative cells and spores into the CDi-screen in the presence and absence of a cultured fecal microbiota and incubated for 48h. To demonstrate its utility, we investigated the effect of the human milk oligosaccharide 2’-Fucosyllactose (2’-FL) at 4 and 8 mg/mL on C. difficile outgrowth and toxin production in the CDi-screen. The test conditions were sampled after 24 and 48 hours. C. difficile -specific primers were used to monitor C. difficile growth via qPCR and barcoded 16S rRNA gene amplicon sequencing facilitated the in-depth analysis of gut microbial community dynamics.

Results

C. difficile ATCC 43599 proliferated in CDi-SIEM, both when inoculated as spores and as vegetative cells. The strain reached cell numbers expressed as C. difficile genome equivalents of up to 10 8 cells per mL after 24h of incubation. 2’-FL significantly inhibited the outgrowth of the ATTC 43599 strain within a complex human gut microbial community in the CDi-screen. In addition, a dose-dependent modulation of the gut microbial community composition by 2’-FL supplementation was detected, with a significant increase in the relative abundance of the genus Blautia in the presence of 2’-FL.

Conclusion

The CDi-screen is suitable for studying C. difficile proliferation in a complex gut ecosystem and for screening for anti-pathogenic interventions that target C. difficile directly and/or indirectly through interactions with the gut microbiota. Different doses of compounds such as in this study the dose of the human milk oligosaccharide 2’-FL can be screened for efficacy in the inhibition of C. difficile proliferation.
Drivers and characteristics of the Indo-western Pacific Ocean capacitor
Authors: Du Yan , Chen Zesheng , Xie Shang-Ping , Zhang Lianyi , Zhang Ying , Cai Yinan
Published: October 2022

Coherently coupled ocean-atmosphere variability of the tropical Indo-Pacific Oceans gives rise to the predictability of Asian summer climate. Recent advances in Indo-western Pacific Ocean capacitor (IPOC) theory and the relationship with El Niño-Southern Oscillation (ENSO) are reviewed. The IPOC features tropical Indian Ocean (TIO) warming and an anomalous anticyclonic circulation over the western North Pacific (WNPAAC), the latter driving water vapor transport to East Asia and causing extreme events, e.g., heavy rainfalls from central China to Japan during the boreal summer. IPOC events often occur in post-ENSO summers, but the significant TIO warming could sustain the WNPAAC without a strong El Niño, forced instead by a strong antecedent positive Indian Ocean Dipole (IOD). In latter cases, the Indian Ocean and WNP act as a self-sustaining system, independent of external forcings. El Niño or positive IOD induces the oceanic downwelling Rossby waves and thermocline warming in the southwest TIO, leading to SST warming and a “C-shaped” wind anomaly during winter and early spring. Furthermore, the southwest TIO downwelling Rossby waves reflect as oceanic Kelvin waves on the African coast. In the early summer, the resultant southeast TIO SST warming induces a second “C-shaped” wind anomaly. Both southwest and southeast TIO warming contribute to the WNPAAC. The WNPAAC modulates the water vapor pathways to East Asia in the late spring and summer, which mostly converge over the South China Sea and adjacent regions before flowing further to the north. More water vapor is transported from the western Pacific warm pool and less from the southern hemisphere and the Indian Ocean. The enhanced Asian Summer monsoon and moisture content lead to extreme rainfalls in central China and Japan during the boreal summer.
Drivers of upper ocean heat content extremes around New Zealand revealed by Adjoint Sensitivity Analysis
Authors: Kerry Colette , Roughan Moninya , Azevedo Correia de Souza Joao Marcos
Published: October 2022

Marine heatwaves can have devastating ecological and economic impacts and understanding what drives their onset is crucial to achieving improved prediction. A key knowledge gap exists around the subsurface structure and temporal evolution of MHW events in continental shelf regions, where impacts are most significant. Here, we use a realistic, high-resolution ocean model to identify marine heatwaves using upper ocean heat content (UOHC) as a diagnostic metric. We show that, embedded in the inter-annual variability of UOHC across the Tasman Sea, regional UOHC around New Zealand varies at short temporal and spatial scales associated with local circulation which drives the onset of extreme events with median duration of 5–20 days. Then, using a novel application of Adjoint Sensitivity Analysis, we diagnose the regional drivers of extreme UOHC events and their 3-dimensional structure. We compute the sensitivity of UOHC to changes in the ocean state and atmospheric forcing over the onset of MHW events using ensembles of between 34 and 64 MHW events across 4 contrasting regions over a 25-year period. The results reveal that changes in regional UOHC on short (5-day) timescales are largely driven by local ocean circulation rather than surface heat fluxes. Where the circulation is dominated by boundary currents, advection of temperature in the mixed layer dominates the onset of extreme UOHC events. Higher magnitude MHW events are typically associated with shallower mixed layer and thermocline depths, with higher sensitivity to temperature changes in the upper 50–80 m. On the west coast, where boundary currents are weak, UOHC extremes are sensitive to density changes in the upper 1,000 m and likely caused by downwelling winds. Our results highlight the importance of understanding the different temporal and spatial scales of UOHC variability. Understanding the local circulation associated with heat content extremes is an important step toward accurate MHW predictability in economically significant shelf seas.
Evaluating replicability of ten influential research on sensory marketing
Authors: Motoki Kosuke , Iseki Sayo
Published: October 2022

We attempted to evaluate the replicability and generalizability of ten influential research on sensory marketing by conducting a high-powered and pre-registered replication in online settings in non-WEIRD consumers. The results revealed that only 20% of findings could be successfully replicated, and their effect sizes are as half as the original ones. Two successful studies had relatively larger sample sizes, used sound symbolism, and employed within-participants manipulation of senses. No studies involving visual factors, between-participant manipulation of senses, or interactions between factors could be replicated. Our findings reveal an initial estimate of the replicability and generalizability of sensory marketing.
The relationship between atherosclerotic disease and relapse during ATD treatment
Authors: Zhu Xinxin , Zhang Yaguang , Zhao Xiaoyu , Zhang Xiaona , Ru Zixuan , Wu Yanmeizhi , Yang Xu , Hou Boyu , Qiao Hong
Published: October 2022

Background

Clinical relapse is a potential risk for traditional antithyroid drug (ATD) treatment in hyperthyroid patients. Evidence suggests that atherosclerotic disease is closely associated with hyperthyroidism, while the relationship between atherosclerosis and relapse remains unclear.

Methods

Two hundred and twenty-five patients with GD who underwent ATD as their first treatment were studied; 88 and 137 patients were categorized as drug reduction relapse and drug reduction remission, respectively. Logistic regression was used to analyze risk factors of drug reduction relapse in patients with GD.

Results

During a median of 48 months followed up 88 patients who relapsed. According to multivariate analyses, atherosclerosis related diseases, FT4, goiter, and anxiety rating scores are independent risk factors for drug reduction. According to K-M survival analysis, patients with atherosclerosis related diseases, FT4 > 18.82 pmol/L, anxiety rating scores > 23, and gradation of goiter ≥ Grade II had a higher risk of relapse than those with lower levels. ROC analysis shown atherosclerosis related diseases significantly improved the predictive accuracy of relapse.

Conclusions

Atherosclerotic disease is closely related to the relapse of hyperthyroidism, ATD treatment in hyperthyroid patients with atherosclerosis should be given more attention.
Identification of hub genes and transcription factor regulatory network for heart failure using RNA-seq data and robust rank aggregation analysis
Authors: Tu Dingyuan , Ma Chaoqun , Zeng ZhenYu , Xu Qiang , Guo Zhifu , Song Xiaowei , Zhao Xianxian
Published: October 2022

Background

Heart failure (HF) is the end stage of various cardiovascular diseases with a high mortality rate. Novel diagnostic and therapeutic biomarkers for HF are urgently required. Our research aims to identify HF-related hub genes and regulatory networks using bioinformatics and validation assays.

Methods

Using four RNA-seq datasets in the Gene Expression Omnibus (GEO) database, we screened differentially expressed genes (DEGs) of HF using Removal of Unwanted Variation from RNA-seq data (RUVSeq) and the robust rank aggregation (RRA) method. Then, hub genes were recognized using the STRING database and Cytoscape software with cytoHubba plug-in. Furthermore, reliable hub genes were validated by the GEO microarray datasets and quantitative reverse transcription polymerase chain reaction (qRT-PCR) using heart tissues from patients with HF and non-failing donors (NFDs). In addition, R packages “clusterProfiler” and “GSVA” were utilized for enrichment analysis. Moreover, the transcription factor (TF)–DEG regulatory network was constructed by Cytoscape and verified in a microarray dataset.

Results

A total of 201 robust DEGs were identified in patients with HF and NFDs. STRING and Cytoscape analysis recognized six hub genes, among which ASPN, COL1A1, and FMOD were confirmed as reliable hub genes through microarray datasets and qRT-PCR validation. Functional analysis showed that the DEGs and hub genes were enriched in T-cell-mediated immune response and myocardial glucose metabolism, which were closely associated with myocardial fibrosis. In addition, the TF–DEG regulatory network was constructed, and 13 significant TF–DEG pairs were finally identified.

Conclusion

Our study integrated different RNA-seq datasets using RUVSeq and the RRA method and identified ASPN, COL1A1, and FMOD as potential diagnostic biomarkers for HF. The results provide new insights into the underlying mechanisms and effective treatments of HF.
Utility of vector flow mapping technology in quantitative assessment of carotid wall shear stress in hypertensive patients: A preliminary study
Authors: He Lan , Cai Yundan , Feng Yuhong , Wang Wenwen , Feng Tienan , Shen E. , Yang Shaoling
Published: October 2022

Background

Blood flowing in the arterial lumen acts on the surface of the vessel wall to form wall shear stress (WSS). To date, there has been limited research on the utility of non-invasive technology in the accurate quantification of carotid WSS in patients with hypertension (HP).

Objective

The present study aimed to explore the usage of vascular vector flow mapping (VFM) in the quantitative assessment of carotid WSS in hypertensive patients at an early stage and to validate its clinical utility.

Methods

A total of 50 individuals confirmed without carotid plaques were grouped into a HP group (n = 25) and a control (CON) group (n = 25) according to blood pressure. An ALOKA LISENDO 880 Color Doppler Ultrasound with a L441 3–15 MHZ probe was used to obtain a longitudinal section scan to determine the regions of interests (ROIs) of the common carotid artery. VFM-based WSS measurements were obtained by selecting the ROI with optimal image quality from three full cardiac cycles. WSS-derived measurements, including WSSmax, WSSmin, and WSSmean, were analyzed and compared between the HP and CON groups. In addition, the correlations between WSS-derived measurements and the carotid artery intima-media thickness (IMT) were also analyzed.

Results

There were significant statistical differences in WSSmax and WSSmean between patients in the HP and CON groups. Specifically, the HP group had significantly decreased WSSmax and WSSmean compared to the CON group (WSSmax: 1.781 ± 0.305 Pa vs. 2.286 ± 0.257 Pa; WSSmean: 1.276 ± 0.333 Pa vs. 1.599 ± 0.293 Pa, both p < 0.001). However, there was no statistical difference in WSSmin between the groups (0.79 ± 0.36 vs. 0.99 ± 0.42, p = 0.080). Additionally, Spearman’s correlation analysis indicated that the WSS-derived parameters were negatively correlated with the IMT (p < 0.001).

Conclusion

Vascular VFM technology shows promising results in the quantitative assessment of difference in hemodynamics of the vascular flow field between patients with HP and normal controls. Difference in WSS may serve as a potential predictor for the development of arteriosclerosis risks.
Recurrent acute myocarditis: An under-recognized clinical entity associated with the later diagnosis of a genetic arrhythmogenic cardiomyopathy
Authors: Ollitrault Pierre , Al Khoury Mayane , Troadec Yann , Calcagno Yoann , Champ-Rigot Laure , Ferchaud Virginie , Pellissier Arnaud , Legallois Damien , Milliez Paul , Labombarda Fabien
Published: October 2022

Background

Myocardial inflammation has been consistently associated with genetic arrhythmogenic cardiomyopathy (ACM) and it has been hypothesized that episodes mimicking acute myocarditis (AM) could represent early inflammatory phases of the disease.

Objective

We evaluated the temporal association between recurrent acute myocarditis (RAM) episodes and the later diagnosis of a genetic ACM.

Materials and methods

Between January 2012 and December 2021, patients with RAM and no previous cardiomyopathy were included (Recurrent Acute Myocarditis Registry, NCT04589156). A follow-up visit including clinical evaluation, resting and stress electrocardiogram, cardiac magnetic resonance imaging, and genetic testing was carried out. Endpoints of the study was the incidence of both ACM diagnosis criteria and ACM genetic mutation at the end of follow-up.

Results

Twenty-one patients with RAM were included and follow-up was completed in 19/21 patients (90%). At the end of follow-up, 3.3 ± 2.9 years after the last AM episode, 14/21 (67%) patients with an ACM phenotype (biventricular: 10/14, 71%; left ventricular: 4/14, 29%) underwent genetic testing. A pathogenic or likely pathogenic mutation was found in 8/14 patients (57%), 5/8 in the Desmoplakin gene, 2/8 in the Plakophillin-2 gene, and 1/8 in the Titin gene. Family history of cardiomyopathy or early sudden cardiac death had a positive predictive value of 88% for the presence of an underlying genetic mutation in patients with RAM.

Conclusion

RAM is a rare entity associated with the latter diagnosis of an ACM genetic mutation in more than a third of the cases. In those patients, RAM episodes represent early inflammatory phases of the disease. Including RAM episodes in ACM diagnosis criteria might allow early diagnosis and potential therapeutic interventions.
Badger vs. beaver patterns in Romanian student life during the pandemic. A two-wave longitudinal approach
Authors: Nadolu Bogdan , Petrescu Magdalena
Published: October 2022

We have already experienced almost two years of COVID-19 pandemic related problems, stress and negative feelings. All over the world, various restrictions have been imposed to reduce the spread of the virus. A particular social category directly affected by the COVID-19 restrictions is that of students. In Romania, classes have been held online from March 2020 until April 2022 for a large part of the higher education system. How have students been affected by these semesters of online classes? This paper sets out to answer this research question on the basis of two sociological surveys, applied online in May 2020 (N = 518) and in May 2021 (N = 206). Its main finding is that there are two different patterns students employ in order to cope with the limitations imposed by the pandemic restrictions: the badger approach, in which they take refuge in leisure activities, and the beaver approach, involving more dynamic and sustainable behaviors.
Getting to the CoRe of Collaborative Online International Learning (COIL)
Authors: Borger Jessica Geraldine
Published: October 2022

In response to the COVID-19 pandemic in 2020, there was a worldwide pivot of education to online communication and the utilization of diverse digital technologies to enhance global learning and foster cultural understanding. Within higher education, educators faced unprecedented challenges in the conversion of face-to-face interactions into online, virtual classrooms, with many educators unprepared and untrained to do so. Yet, the introduction of online digital technologies for pedagogical interactions expanded the internationalization of previously limited curriculum prospects, to create global interconnectedness with the potential to invoke Students’ awareness and appreciation of cultural differences in communication, leadership, and conflict. The development of international knowledge, pedagogical knowledge, and the linkage between the two is key for the internationalization of the curriculum. With the growth of new digital communication, learning opportunities such as Collaborative Online International Learning (COIL), aims to foster the development of intercultural competencies (ICC) in our students for future career advancement in an expanding global community. Despite the acknowledgment that faculty are underprepared and lack pedagogical knowledge to translate their lived experiences into their curriculum, there remains a tenable lack of available tools for educators to facilitate students actively participating in objective, equitable and inclusive intercultural communication. Herein, is proposed the novel application of a conceptual tool, a “content representation” or CoRe matrix, which explicitly separates a particular topic into divergent, yet linked dimensions of the knowledge and skills attributed to its content, teaching, and learning. It was hypothesized the CoRe tool could be applied to enhance an educator’s PCK of ICC, providing the valuable link between international and pedagogical knowledge, for effective internationalization of the curriculum. The novel ICC CoRe matrix successfully addressed the 4 dimensions of ICC demonstrating the robust nature of the application of the CoRe matrix in the development of an educator’s ICC PCK in the COIL classroom. With the exponential increase in digital technologies creating dynamic worldwide networks in education and the workplace, the development of conceptual tools such as the ICC CoRe matrix has the potential to develop and integrate an educator’s pedagogical knowledge with ICC, to support the development of effective, objective and inclusive student participation in global twenty-first-century classrooms and beyond.
Osteopontin, a bridge links osteoarthritis and osteoporosis
Authors: Bai Rui-Jun , Li Yu-Sheng , Zhang Fang-Jie
Published: October 2022

Osteoarthritis (OA) is the most prevalent joint disease characterized by degradation of articular cartilage, inflammation, and changes in periarticular and subchondral bone of joints. Osteoporosis (OP) is another systemic skeletal disease characterized by low bone mass and bone mineral density (BMD) accompanied by microarchitectural deterioration in bone tissue and increased bone fragility and fracture risk. Both OA and OP are mainly affected on the elderly people. Recent studies have shown that osteopontin (OPN) plays a vital role in bone metabolism and homeostasis. OPN involves these biological activities through participating in the proliferation, migration, differentiation, and adhesion of several bone-related cells, including chondrocytes, synoviocytes, osteoclasts, osteoblasts, and marrow mesenchymal stem cells (MSCs). OPN has been demonstrated to be closely related to the occurrence and development of many bone-related diseases, such as OA and OP. This review summarizes the role of OPN in regulating inflammation activity and bone metabolism in OA and OP. Furthermore, some drugs that targeted OPN to treat OA and OP are also summarized in the review. However, the complex mechanism of OPN in regulating OA and OP is not fully elucidated, which drives us to explore the depth effect of OPN on these two bone diseases.
Association of thyroid dysfunction and COVID-19: A systematic review and meta-analysis
Authors: Darvishi Mohammad , Nazer Mohammad Reza , Shahali Hamze , Nouri Majid
Published: October 2022

This systematic review and meta-analysis was conducted to evaluate the effect of COVID-19 on thyroid function and the role of thyroid hormones alterations in predicting the severity of COVID-19. Online databases, including Scopus, Medline/PubMed, EMBASE, Google Scholar, and Cochrane were searched up to August 2, 2022. After screening titles, abstracts, and full manuscripts, respectively, 30 reports were enrolled. The risk of bias (ROB) was evaluated using the QUADAS-2 tool. In addition, odds ratio (OR) and hazard ratio (HR) analysis for assessing the OR of abnormal thyroid function tests (TFT) in predicting the COVID-19 severity and poor outcomes. Among 30 enrolled studies, ROB of the current study is estimated low to moderate. The average number of patients in each study was 325 (range: 40-3,703), with an overall mean age of 57.6, and the female proportion of 40.4%. Overall, the pooled analysis showed that the prevalence of thyroid dysfunction among 9,707 COVID-19 cases was 15%. Among mild to moderate COVID-19 patients, 6.2% had abnormal TFT, and among patients who experienced severe to critical COVID-19, 20.8% had abnormal TFT. The pooled OR for abnormal TFT and the severity of COVID-19 obtained from 3,865 COVID-19 patients was 3.77 (2.03, 6.99). The pooled HR of TSH level of COVID-19 mortality was 1.57 (0.91, 2.72). Our results demonstrate a high prevalence of thyroid dysfunction in COVID-19, and that among patients severe cases had a 3.77-fold higher risk of abnormal TFT compared to mild to moderate COVID-19. Further studies are required to evaluate the longer-term prognostic role of thyroid dysfunction in severe COVID-19, and investigate potential therapeutic strategies.
Energy management of renewable energy-based microgrid system with HESS for various operation modes
Authors: Kumar G. V. Brahmendra , Palanisamy K.
Published: October 2022

This paper proposes a ramp-rate control approach for a grid-connected MG with a hybrid energy storage system. Distributed energy sources (DERs), such as solar photovoltaic (PV) and wind, combined with energy storage (ES) and controllable loads, are critical to a power grid that can handle the intermittent nature of renewable energy sources. Therefore, the complexity of the system is increasing as researchers move towards a more renewable based power grid. An energy management system (EMS) for microgrids must consider the power available in RESs as well as the storage capacity of energy storage devices (ESSs). Modern MGs include a wide range of converters for a variety of applications, including distributed generation interconnection, grid integration, energy storage management systems, and demand management, among others. So, the ramp-rate control smooths fluctuations in photovoltaic power, which increases system reliability. In the proposed system, 80 V DC is used to supply high and low power DC loads. The suggested system can extract the maximum amount of energy from RESs, maintain efficient ESS management, and achieves quick DC-link voltage regulation with settling time of 230 ms throughout all operating modes. These conditions are met by the energy management system, which gives the MG with operational capability and ensures its reliability. The MG with proposed features and EMS was validated using the MATLAB/Simulink environment, and results were obtained using the Hardware-in-the-Loop (HIL) experimental test bench. The proposed small-scale RES-based MG can be used to develop and test algorithms for a wide range of MG applications.
Impact of Chinese fiscal decentralization on industrial green transformation: From the perspective of environmental fiscal policy
Authors: Qi Yawei , Zou Xianya , Xu Mo
Published: October 2022

To accomplish the goals of carbon mitigation, industrial green transformation is an inevitable requirement for achieving high-quality economic development. Based on the data of 30 provinces in China from 2007 to 2017, this paper uses projection pursuit model and entropy method to calculate the industrial green transformation and Chinese fiscal decentralization. It further employs static and dynamic spatial Durbin model to explore the impact of Chinese fiscal decentralization on industrial green transformation by the environmental fiscal policy. The study finds that: 1) China’s industrial green transformation presents an unbalanced state with high in the east and low in the west, which has a positive spatial spillover among provinces. 2) Fiscal decentralization is significantly conducive to the industrial green transformation, while the spatial spillover of fiscal decentralization is negative. Moreover, fiscal decentralization affects the industrial green transformation by environmental fiscal policy, in of which environmental fiscal expenditure is the main path. 3) From the perspective of heterogeneity of fiscal decentralization, the impact of fiscal expenditure decentralization in promoting industrial green transformation is significantly greater than that of fiscal revenue decentralization. In terms of heterogeneity of regional location, fiscal decentralization in the eastern and central regions plays a role in accelerating industrial green transformation, while it has an obstacle impact in the western region. In terms of market-based heterogeneity, Fiscal decentralization in high-market areas facilitates the green transformation of industry, while in low-market areas is the opposite.