bluuebunny/crossref_metadata_2025 huggingface dataset:
Data-Driven Personalized Learning Path Planning Based on Cognitive Diagnostic Assessments in MOOCs
Authors: Jiang Bo , Li Xinya , Yang Shuhao , Kong Yaqi , Cheng Wei , Hao Chuanyan , Lin Qiaomin
Published: April 2022

Personalized learning paths aim to save learning time and improve learning achievements by providing the most appropriate learning sequence for heterogeneous students. Most existing methods that construct personalized learning paths focus on students’ characteristics or knowledge structure, while ignoring the critical roles of learning states. This study describes a dynamic personalized learning path planning algorithm to recommend appropriate knowledge points for online students based on their learning states and the difficulty of each knowledge point. The proposed method first calculates the difficulty of knowledge points automatically and constructs a knowledge difficulty model. Then, a dynamic knowledge mastery model is built based on learning behavior and normalized test scores. Finally, a path that satisfies students’ personalized changing states is generated. To achieve the aforementioned goal, a novel method that calculates the difficulty of knowledge points automatically is proposed. Moreover, the personalized learning path planning method proposed in this research is not limited to a particular course. To evaluate the method, we use a series of approaches to verify the impact of the personalized path on student learning. The experimental results demonstrate that the proposed algorithm can effectively generate personalized learning paths. Results demonstrate that the personalized path proposed by the algorithm can improve effective behavior rates, course completion rates and learning efficiency. Results also show that the personalized learning paths based on student states would help students to master knowledge.
On the Unification of Legged and Aerial Robots for Planetary Exploration Missions
Authors: Haluška Jakub , Koval Anton , Nikolakopoulos George
Published: April 2022

In this article, we address the task of developing a unified solution that incorporates quadruped and aerial robots for planetary exploration missions. The designing process takes recommendations provided by Boston Dynamics for building custom payloads for the Spot robot, as well as its kinematic constraints. The unification task itself encompasses design of a passive drone landing platform as a hardware link between the Spot robot and the drone, which has active locking and unlocking capabilities required to securely keep the drone on the Spot independently whether it is standing or moving. Thus, in the designed unification solution, the landing platform does not impact the overall robot mobility and has no interference with the robot’s legs. The initial solution design was extensively evaluated in a series of tests at the laboratory, which demonstrated its viability.
Evaluation of the Acceleration Vibration Signal for Aggregates of the Horizontal Drilling Stand
Authors: Flegner Patrik , Kačur Ján , Durdán Milan , Laciak Marek
Published: April 2022

During the operation of each machine, there are dynamic effects causing vibrations. Such a device is also an experimental horizontal drilling stand with aggregates, i.e., a direct current motor (DC), a pump, and a hydro-generator. During their operation, unwanted vibration acceleration signals are generated. It is clear that the accompanying vibration signal carries integrating information about the current state of the drilling rig. Vibration signal processing methods for the time and frequency domains were used. The results of time-domain processing showed significant differences in time waveforms, statistical characteristics, and auto-correlation functions. The auto-correlation function pointed to the periodicity and dependence of the vibrational signal samples. Based on the acquired knowledge, the signals were classified, and a strong source of vibration was determined. Noise is superimposed on the harmonic components of the signals. Amplitude and power spectra were constructed in the frequency domain. Dominant frequencies were identified for each investigated mode in the operating mode. Power spectra removed less significant frequencies and focused on the dominant ones. Time-frequency spectrograms revealed significantly higher frequency bands. The proposed methods can be implemented in diagnosing the operation of the machine and aggregates, determining the source of the greatest vibrations, wear of parts of the equipment such as the drill bit, and recognition of the overall condition of the equipment.
New Supply-Air Solar Wall with Thermal Storage Designed to Preheat Fresh Air: Development of a Numerical Model Adapted to Building Energy Simulation
Authors: Ibrahim Rima Abou , Tittelein Pierre , Lassue Stéphane , Chehade Fadi Hage , Zalewski Laurent
Published: April 2022

Façades built with integrated passive solar systems hold great promise for improving the energy performance of buildings and achieving indoor comfort conditions. Among these techniques, solar air preheating systems with different configurations have proven their ability to reduce the energy consumption of buildings during the heating season. In this study, we propose a ventilated solar wall (VSW) with a thermal storage unit intended for preheating ventilation air. The final aim of this study is to determine the thermal performance of the studied VSW over a significant time period (during the heating season) under various climatic conditions when it is integrated into the building envelope. Therefore, for this purpose, a simplified model was developed to be coupled to a building energy simulation (BES) code. The results from the detailed steady-state 2D computational fluid dynamics (CFD) model show that the thermal efficiency of the VSW ranged from 55% to 70% as the air mass flow rate increased from 0.008 kg/s to 0.02 kg/s for a surface of 2.15 m2. These results were used to evaluate the convective heat transfer coefficients in the two air cavities and to validate the simplified model. The results indicate good agreement between the two models.
MOMIC: A Multi-Omics Pipeline for Data Analysis, Integration and Interpretation
Authors: Madrid-Márquez Laura , Rubio-Escudero Cristina , Pontes Beatriz , González-Pérez Antonio , Riquelme José C. , Sáez Maria E.
Published: April 2022

Background and Objectives: The burst of high-throughput omics technologies has given rise to a new era in systems biology, offering an unprecedented scenario for deriving meaningful biological knowledge through the integration of different layers of information. Methods: We have developed a new software tool, MOMIC, that guides the user through the application of different analysis on a wide range of omic data, from the independent single-omics analysis to the combination of heterogeneous data at different molecular levels. Results: The proposed pipeline is developed as a collection of Jupyter notebooks, easily editable, reproducible and well documented. It can be modified to accommodate new analysis workflows and data types. It is accessible via momic.us.es, and as a docker project available at github that can be locally installed. Conclusions: MOMIC offers a complete analysis environment for analysing and integrating multi-omics data in a single, easy-to-use platform.
Land–Air–Wall Cross-Domain Robot Based on Gecko Landing Bionic Behavior: System Design, Modeling, and Experiment
Authors: Huang Chengwei , Liu Yong , Wang Ke , Bai Bing
Published: April 2022

Based on the bionic behavior of geckos, this paper presents a land–air–wall cross-domain robot which can fly in air, run on the ground, and adhere to various wall surfaces. When geckos jump and adsorb to vertical surfaces such as trunks, they can still adsorb to the wall with a large contact speed. Inspired by this phenomenon, we analyze the mechanism, apply it to our robot, and optimize the design of the robot structure. In addition, geckos use their tails to adjust posture to achieve abdominal landing during the process of falling. Inspired by this phenomenon, based on the rotor lift/power curve, we optimize the center of gravity by controlling the servo angle. The initial center of gravity offset of the robot is estimated by the extended state observer. The method reduces the distance between the center of gravity and the geometric center, balances the load of each propeller, and finally reduces the total power. The experiment and simulation results validate the feasibility of the land–air–wall cross-domain robot and the bionic methods.
An Optimization-Based Diabetes Prediction Model Using CNN and Bi-Directional LSTM in Real-Time Environment
Authors: Madan Parul , Singh Vijay , Chaudhari Vaibhav , Albagory Yasser , Dumka Ankur , Singh Rajesh , Gehlot Anita , Rashid Mamoon , Alshamrani Sultan S. , AlGhamdi Ahmed Saeed
Published: April 2022

Diabetes is a long-term illness caused by the inefficient use of insulin generated by the pancreas. If diabetes is detected at an early stage, patients can live their lives healthier. Unlike previously used analytical approaches, deep learning does not need feature extraction. In order to support this viewpoint, we developed a real-time monitoring hybrid deep learning-based model to detect and predict Type 2 diabetes mellitus using the publicly available PIMA Indian diabetes database. This study contributes in four ways. First, we perform a comparative study of different deep learning models. Based on experimental findings, we next suggested merging two models, CNN-Bi-LSTM, to detect (and predict) Type 2 diabetes. These findings demonstrate that CNN-Bi-LSTM surpasses the other deep learning methods in terms of accuracy (98%), sensitivity (97%), and specificity (98%), and it is 1.1% better compared to other existing state-of-the-art algorithms. Hence, our proposed model helps clinicians obtain complete information about their patients using real-time monitoring and can check real-time statistics about their vitals.
Influence of Petrogenesis on the Engineering Properties of Ultramafic Aggregates and on Their Suitability in Concrete
Authors: Petrounias Petros , Giannakopoulou Panagiota P. , Rogkala Aikaterini , Sideridis Alkiviadis , Koutsovitis Petros , Lampropoulou Paraskevi , Koukouzas Nikolaos , Pomonis Panagiotis , Hatzipanagiotou Konstantin
Published: April 2022

This study focuses on the use of petrology as a useful tool in construction applications (i.e., concrete). More specifically, this study investigates how the petrogenetic characteristics of ultramafic rocks derived from ophiolite complexes (Veria–Naousa, Gerania) can act as a key tool for the prediction of the final behaviour of ultramafic aggregates as concrete aggregates. For this reason, their petrographic, chemical and mineralogical characteristics were examined and correlated with their engineering properties for evaluating their suitability as concrete aggregates. This study had come up, for the first time, that the genesis environment of the ultramafic rocks is the determinant factor for their physico-mechanical characteristics. Their suitability is relevant to the impact of their mineralogical and structural characteristics both from the two different ophiolite complexes (Veria–Naousa and Gerania). Except serpentinization, the basic alteration process-index of ultramafic rocks, there are also other chemical indices which can be used for ultramafic rocks that may determine their properties. In this context the term ‘fertility rate’ (FR) was introduced which may characterize ultramafic rocks as fertile or not. Furthermore, the Ultramafic Rock Health Index (U.R.H.I.) as well as the Normalized U.R.H.I. (U.R.H.I.N) was also introduced and correlated with the engineering properties of the investigated aggregate rocks. The last index aims to assess and quantify the overall health conditions, encompassing the two major modifying factors that include removal of primary mineral phases, as well as the extent of serpentinization. The main conclusion of this paper is that the genesis environment of the ultramafic rocks is the critical factor that determines their mineralogical, petrographic and chemical characteristics which consequently determines the basic engineering properties of rocks that determine their suitability or not as concrete aggregates.
Multi-Sensor Approach Combined with Pedological Investigations to Understand Site-Specific Variability of Soil Properties and Potentially Toxic Elements (PTEs) Content of an Industrial Contaminated Area
Authors: Vingiani Simona , Agrillo Antonietta , De Mascellis Roberto , Langella Giuliano , Manna Piero , Mileti Florindo Antonio , Terribile Fabio
Published: April 2022

A combination of indirect soil investigation by proximal soil sensors (PSS), based on geophysical (ARP, EMI), physical (Cone Index –CI– by ultrasound penetrometry) and spectrometric (γ-rays) techniques, as well as pedological surveys, was applied in the field to assess the spatial variability of soil pollution and physical degradation in an automobile-battery recycling plant in southern Italy. Five homogeneous zones (HZs) were identified by the PSS and characterized by soil profiles. CI measurements and field analysis showed clear features of physical (i.e., soil compaction, massive structure) degradation. XRF in situ (on profiles) analysis using portable equipment (pXRF) showed Pb, Cd and As concentrations exceeding the contamination thresholds provided by the Italian regulation for industrial land use up to 20 or 100 cm of depth. Hence, a validation procedure, based on pXRF field survey, was applied to the PSS approach used for the HZs identification. High consistency was found between the HZs and the PTEs in the most contaminated areas. Significant negative Pearson correlation coefficients were found between γ-rays dose rate and Pb, Cu, Zn, As and Ni; positive ones were found between γ-rays and autochthonous lithogenic elements (V, Ti, Mn, K, Sr, Nb, Zr, Rb, Th), confirming that higher radionuclide activity correlated with lower pollution levels.
Optical Accelerometers for Detecting Low-Frequency Micro-Vibrations
Authors: Lei Ying-Jun , Li Rui-Jun , Zhang Lian-Sheng , Hu Peng-Hao , Huang Qiang-Xian
Published: April 2022

Optical accelerometers are high-precision inertial sensors that use optical measurement technology to achieve high-precision and electromagnetic interference-resistant acceleration measurements. With the intensive research and development of optical accelerometers in recent years, their applications in inertial navigation, structural health monitoring, precision vibration isolation systems, wind turbine fault monitoring, earthquake monitoring, and other low-frequency vibration detection have flourished. Optical accelerometers have various schemes; however, their characteristics vary considerably due to different optical modulation schemes. This study aims to address the lack of systematic evaluation of currently available low-frequency optical accelerometers. Optical accelerometers can be classified into four categories in accordance with their optical modulation schemes: optical path-, optical intensity-, optical phase-, and optical wave-length-modulated accelerometers. The typical performance, advantages and disadvantages, and possible application scenarios of various optical accelerometers are summarized. This study also presents the current status and trends of low-frequency optical accelerometers in consideration of the growing demand for high-precision, low-frequency acceleration measurements.
Efficient Inorganic/Organic Acid Leaching for the Remediation of Protogenetic Lead-Contaminated Soil
Authors: Xiao Longheng , Cheng Xiang , Zhang Tianhua , Guo Min , Zhang Mei
Published: April 2022

In this study, inorganic acid and organic acid were used to leach and remediate superheavy, lead-contaminated protogenetic soil with a lead pollution level of 8043 mg∙kg−1. Among the compounds studied, HCl and citric acid (CA) presented the best effects, respectively. Under the optimal experimental conditions, the remediation efficiency of 0.05 mol∙L−1 CA reached 53.6%, while that of 0.2 mol∙L−1 HCl was 70.3%. According to the lead morphology analysis, CA and HCl have certain removal ability to different fractions of lead. Among them, the removal rates of acid-soluble lead in soil by HCl and CA are 93% and 83%, and the soil mobility factor (MF) value decreased from 34.4% to 7.74 % and 12.3%, respectively, indicating that the harm of lead in soil was greatly reduced. Meanwhile, the leaching mechanisms of CA and HCl were studied. The pH values of the soil after leaching with HCl and CA were 3.88 and 6.97, respectively, showing that HCl leaching has caused serious acidification of the soil, while the process of CA leaching is more mild. CA has a relatively high remediation efficiency at such a low concentration, especially for the highly active acid-soluble fraction lead when maintaining the neutrality of the leached soil. Hence, CA is more suitable for the remediation of lead-contaminated soil.
SOH Estimation of Li-Ion Battery Using Discrete Wavelet Transform and Long Short-Term Memory Neural Network
Authors: Park Min-Sick , Lee Jong-kyu , Kim Byeong-Woo
Published: April 2022

The state of health (SOH) of a lithium-ion battery (LIB) should be accurately estimated to ensure its safe operation under various driving conditions for electric vehicles. To estimate the SOH of LIBs, it is necessary to develop a technique that can properly process data with nonlinear characteristics related to the voltage and temperature of various electrochemical reactions in the batteries. To this end, we adopted wavelet transform methods to facilitate feature extraction for the preprocessing of nonlinear characteristic data from LIBs. Convolutional neural network (CNN) and long short-term memory (LSTM) techniques were used for the lithium-ion SOH estimation using the wavelet transform method. SOH estimation models using either the conventional data preprocessing technology normalization or wavelet transform method were compared. The SOH estimation accuracy of the model in which the wavelet transform was applied to the LSTM learning technology was 98.92%, and it was confirmed that the performance was improved compared with that of the normalization technology. In summary, this paper proposes a method that can improve the SOH estimation accuracy of LIBs compared to conventional methods by using data with nonlinear characteristics related to intrinsic changes in the voltage and temperature of LIBs.
L2-Norm Based a Posteriori Error Estimates of Compressible and Nearly-Incompressible Elastic Finite Element Solutions
Authors: Ahmed Mohd. , Singh Devinder , AlQadhi Saeed , Kahla Nabil Ben
Published: April 2022

The displacement and stress-based error estimates in a posteriori error recovery of compressible and nearly-incompressible elastic finite element solutions is investigated in the present study. The errors in the finite element solutions, i.e., in displacement and stress, at local and global levels are computed in L2-norm of quantity of interest, namely, displacements and gradients. The error estimation techniques are based on the least square fitting of higher order polynomials to stress and displacement in a patch comprising of node/elements surrounding and including the node/elements under consideration. The benchmark examples of compressible and incompressible elastic bodies, with known solutions employing triangular discretization schemes, are implemented to measure the finite element errors in displacements and gradients. The mixed formulation involving displacement and pressure is used for incompressible elastic analysis. The performance of error estimation is measured in terms of convergence properties, effectivity and mesh required for predefined precision. The error convergence rate, in FEM original solution, recovered solution using displacement recovery-based and stress-based error recovery technique for stresses, are obtained as (1.9714, 2.8999, and 2.5018) and (0.9818, 1.7805, and 1.4952) respectively for compressible and incompressible self-loaded elastic plate benchmark example using higher order triangular elements. It is concluded from the study that displacement fitting technique for extracting higher order derivatives shows a very effective technique for recovery of compressible and nearly-incompressible finite element analysis errors.
Interfacial Properties of H2O+CO2+Oil Three-Phase Systems: A Density Gradient Theory Study
Authors: Yang Yafan , Zhu Weiwei , Ji Yukun , Wang Tao , Zhao Guangsi
Published: April 2022

The interfacial property of H2O+CO2+oil three-phase systems is crucial for CO2 flooding and sequestration processes but was not well understood. Density gradient theory coupled with PC-SAFT equation of state was applied to investigate the interfacial tension (IFT) of H2O+CO2+oil (hexane, cyclohexane, and benzene) systems under three-phase conditions (temperature in the range of 323–423 K and pressure in the range of 1–10 MPa). The IFTs of the aqueous phase+vapor phase in H2O+CO2+oil three-phase systems were smaller than the IFTs in H2O+CO2 two-phase systems, which could be explained by enrichment of oil in the interfacial region. The difference between IFTs of aqueous phase+vapor phase in the three-phase system and IFTs in H2O+CO2 two-phase system was largest in the benzene case and smallest in the cyclohexane case due to different degrees of oil enrichment in the interface. Meanwhile, CO2 enrichment was observed in the interfacial region of the aqueous phase+oil-rich phase, which led to the reduction of IFT with increasing pressure while different pressure effects were observed in the H2O+oil two-phase systems. The effect of CO2 on the IFTs of aqueous phase+benzene-rich phase interface was small in contrast to that on the IFTs of aqueous phase+alkane (hexane or cyclohexane)-rich phase interface. H2O had little effect on the interfacial properties of the oil-rich phase+vapor phase due to the low H2O solubilities in the oil and vapor phase. Further, the spreading coefficients of H2O+CO2 in the presence of different oil followed this sequence: benzene > hexane > cyclohexane.
Carbon and Trace Element Compositions of Total Suspended Particles (TSP) and Nanoparticles (PM0.1) in Ambient Air of Southern Thailand and Characterization of Their Sources
Authors: Inerb Muanfun , Phairuang Worradorn , Paluang Phakphum , Hata Mitsuhiko , Furuuchi Masami , Wangpakapattanawong Prasit
Published: April 2022

The concentration of total suspended particles (TSP) and nanoparticles (PM0.1) over Hat Yai city, Songkhla province, southern Thailand was measured in 2019. Organic carbon (OC) and elemental carbon (EC) were evaluated by carbon aerosol analyzer (IMPROVE-TOR) method. Thirteen trace elements including Al, Ba, K, Cu, Cr, Fe, Mg, Mn, Na, Ni, Ti, Pb, and Zn were evaluated by ICP-OES. Annual average TSP and PM0.1 mass concentrations were determined to be 58.3 ± 7.8 and 10.4 ± 1.2 µg/m3, respectively. The highest levels of PM occurred in the wet season with the corresponding values for the dry seasons being lower. The averaged OC/EC ratio ranged from 3.8–4.2 (TSP) and 2.5–2.7 (PM0.1). The char to soot ratios were constantly less than 1.0 for both TSP and PM0.1, indicating that land transportation is the main emission source. A principal component analysis (PCA) revealed that road transportation, industry, and biomass burning are the key sources of these particles. However, PM arising from Indonesian peatland fires causes an increase in the carbon and trace element concentrations in southern Thailand. The findings make useful information for air quality management and strategies for controlling this problem, based on a source apportionment analysis.
Modeling the Determinants of PM2.5 in China Considering the Localized Spatiotemporal Effects: A Multiscale Geographically Weighted Regression Method
Authors: Yue Han , Duan Lian , Lu Mingshen , Huang Hongsheng , Zhang Xinyin , Liu Huilin
Published: April 2022

Many studies have identified the influences of PM2.5. However, very little research has addressed the spatiotemporal dependence and heterogeneity in the relationships between impact factors and PM2.5. This study firstly utilizes spatial statistics and time series analysis to investigate the spatial and temporal dependence of PM2.5 at the city level in China using a three-year (2015–2017) dataset. Then, a new local regression model, multiscale geographically weighted regression (MGWR), is introduced, based on which we measure the influence of PM2.5. A spatiotemporal lag is constructed and included in MGWR to account for spatiotemporal dependence and spatial heterogeneity simultaneously. Results of MGWR are comprehensively compared with those of ordinary least square (OLS) and geographically weighted regression (GWR). Experimental results show that PM2.5 is autocorrelated in both space and time. Compared with existing approaches, MGWR with a spatiotemporal lag (MGWRL) achieves a higher goodness-of-fit and a more significant effect on eliminating residual spatial autocorrelation. Parameter estimates from MGWR demonstrate significant spatial heterogeneity, which traditional global models fail to detect. Results also indicate the use of MGWR for generating local spatiotemporal dependence evaluations which are conditioned on various covariates rather than being simple descriptions of a pattern. This study offers a more accurate method to model geographic events.
Skull Vibration-Induced Nystagmus and High Frequency Ocular Vestibular-Evoked Myogenic Potentials in Superior Canal Dehiscence
Authors: Batuecas-Caletrío Ángel , Jara Alejandra , Suarez-Vega Victor Manuel , Marcos-Alonso Susana , Sánchez-Gómez Hortensia , Pérez-Fernández Nicolas
Published: April 2022

Background: Although diagnostic criteria have been established for superior canal dehiscence syndrome, cases in which the diagnosis is not easy are frequent. On those occasions, some tests such as vibration-induced nystagmus or vestibular-evoked myogenic potentials can offer invaluable help due to their high sensitivity and specificity. Methods: We studied 30 patients showing superior canal dehiscence or “near-dehiscence” in a CT scan. Skull vibration-induced nystagmus and high frequency ocular vestibular-evoked myogenic potentials are performed in each patient. The aim of the study is to determine how useful both tests are for detection of superior canal dehiscence or near-dehiscence. Results: Of the 60 temporal bones studied, no dehiscence was the result in 22, near-dehiscence in 17 and a definite finding in 21. In 10/30 patients, there was no SVIN (Skull vibration induced nystagmus) during otoneurological testing, while in 6/30, induced nystagmus was mainly horizontal, and in 14/30 there was vertical up-beating. All patients had a positive oVEMP (Ocular vestibular evoked myiogenic potentials) at 0.5 kHz in both ears and the HFoVEMP (High frequency ocular vestibular evoked myiogenic potentials) response was positive in 25/60 (41.6%) of the ears studied and in 19/30 of the patients evaluated (in 6 it was positive in both ears). Up-beat SVIN will point to a SCD (Superior Canal Dehiscence) mainly when HFoVEMP are present, and when this is negative there is a high probability that it is not a SCD. Conclusions: When SVIN and HFoVEMP results are added (or combined), they not only improve the possibilities of detecting SCD, but also the affected side.
Optimisation of Biomass Production and Nutritional Value of Two Marine Diatoms (Bacillariophyceae), Skeletonema costatum and Chaetoceros calcitrans
Authors: Bastos Carolina R. V. , Maia Inês B. , Pereira Hugo , Navalho João , Varela João C. S.
Published: April 2022

S. costatum and C. calcitrans are two cosmopolitan high-value centric diatoms, with a rich nutritional profile. The following work optimised the culture medium of S. costatum and C. calcitrans cultures, respectively, in a stepwise process as follows: 2.4 mM and 1.2 mM of silicate, 4 mM of nitrate, 100 µM of phosphate, 20 and 80 µM iron, and 0.5 mL L−1 of micronutrients. The results that were obtained revealed an increase in biomass productivity with a 1.8- and 3.2-fold increase in biomass that was produced by S. costatum and C. calcitrans, respectively. The biochemical profile showed an increase in high-value PUFAs such as 2.6-fold and 2.3-fold increase in EPA for S. costatum and C. calcitrans, respectively, whilst a 2.6-fold increase in DHA was detected in S. costatum cultures. The present work provides the basic tools for the industrial cultivation of S. costatum and C. calcitrans with enhanced productivity as well as improved biomass quality, two factors which are highly relevant for a more effective application of these diatoms to aquaculture and nutraceutical production.
SERPINE1 rs6092 Variant Is Related to Plasma Coagulation Proteins in Patients with Severe COVID-19 from a Tertiary Care Hospital
Authors: Fricke-Galindo Ingrid , Buendia-Roldan Ivette , Chavez-Galan Leslie , Pérez-Rubio Gloria , Hernández-Zenteno Rafael de Jesús , Ramos-Martinez Espiridión , Zazueta-Márquez Armando , Reyes-Melendres Felipe , Alarcón-Dionet Aimé , Guzmán-Vargas Javier , Bravo-Gutiérrez Omar Andrés , Quintero-Puerta Teresa , Gutiérrez-Pérez Ilse Adriana , Ortega-Martínez Alejandro , Ambrocio-Ortiz Enrique , Nava-Quiroz Karol J. , Bañuelos-Flores José Luis , Jaime-Capetillo María Esther , Mejía Mayra , Rojas-Serrano Jorge , Falfán-Valencia Ramcés
Published: April 2022

An impaired coagulation process has been described in patients with severe or critical coronavirus disease (COVID-19). Nevertheless, the implication of coagulation-related genes has not been explored. We aimed to evaluate the impact of F5 rs6025 and SERPINE1 rs6092 on invasive mechanical ventilation (IMV) requirement and the levels of coagulation proteins among patients with severe COVID-19. Four-hundred fifty-five patients with severe COVID-19 were genotyped using TaqMan assays. Coagulation-related proteins (P-Selectin, D-dimer, P-selectin glycoprotein ligand-1, tissue plasminogen activator [tPA], plasminogen activator inhibitor-1, and Factor IX) were assessed by cytometric bead arrays in one- and two-time determinations. Accordingly, SERPINE1 rs6092, P-Selectin (GG 385 pg/mL vs. AG+AA 632 pg/mL, p = 0.0037), and tPA (GG 1858 pg/mL vs. AG+AA 2546 pg/mL, p = 0.0284) levels were different. Patients carrying the CT F5-rs6025 genotype exhibited lower levels of factor IX (CC 17,136 pg/mL vs. CT 10,247 pg/mL, p = 0.0355). Coagulation proteins were also different among IMV patients than non-IMV. PSGL-1 levels were significantly increased in the late stage of COVID-19 (>10 days). The frequencies of F5 rs6025 and SERPINE1 rs6092 variants were not different among IMV and non-IMV. The SERPINE1 rs6092 variant is related to the impaired coagulation process in patients with COVID-19 severe.
Commonly Prescribed Anticoagulants Exert Anticancer Effects in Oral Squamous Cell Carcinoma Cells In Vitro
Authors: Ling Li-Qiao R. , Lin Zichen , Paolini Rita , Farah Camile S. , McCullough Michael , Lim Mathew A. W. T. , Celentano Antonio
Published: April 2022

Oral squamous cell carcinoma (OSCC) is the most common head and neck cancer. With anticoagulant usage on the rise, it is important to elucidate their potential effects on tumour biology and interactions with chemotherapeutics. The aim of the present study was to investigate the effects of anticoagulants on OSCC cell lines and their interactions with the drug 5-fluorouracil (5-FU). Cell proliferation was assessed using an MTS in vitro assay in two human OSCC cell lines (H357/H400) and in normal oral keratinocytes (OKF6) treated with the 5-FU (0.2/1/5/10 μg/mL), conventional anticoagulants warfarin (1/5/10/20 μM) and heparin (5/20/80 U), as well as four new oral anticoagulants, dabigatran (5/10/20 μM), rivaroxaban (5/10/20 μM), apixaban (0.1/1/5 μg/mL), and edoxaban (5/10/20 μM). Cell migration was assessed at 3 h intervals up to18 h using a wound healing assay. Our results clearly demonstrate, for the first time, that commonly prescribed anticoagulants exert in vitro antiproliferative effects on OSCC cells. Furthermore, treatment with some anticoagulants reduced the migration of OSCC cell lines. Nevertheless, most of the anticoagulants tested reduced the effectiveness of the chemotherapeutic agent tested, 5-FU, highlighting potential flaws in the current pharmacological management of these patients. Our findings showed the need for the immediate translation of this research to preclinical animal models.
An Insight into Abiotic Stress and Influx Tolerance Mechanisms in Plants to Cope in Saline Environments
Authors: Gul Zarmina , Tang Zhong-Hua , Arif Muhammad , Ye Zhang
Published: April 2022

Salinity is significant abiotic stress that affects the majority of agricultural, irrigated, and cultivated land. It is an issue of global importance, causing many socio-economic problems. Salt stress mainly occurs due to two factors: (1) soil type and (2) irrigation water. It is a major environmental constraint, limiting crop growth, plant productivity, and agricultural yield. Soil salinity is a major problem that considerably distorts ecological habitats in arid and semi-arid regions. Excess salts in the soil affect plant nutrient uptake and osmotic balance, leading to osmotic and ionic stress. Plant adaptation or tolerance to salinity stress involves complex physiological traits, metabolic pathways, the production of enzymes, compatible solutes, metabolites, and molecular or genetic networks. Different plant species have different salt overly sensitive pathways and high-affinity K+ channel transporters that maintain ion homeostasis. However, little progress has been made in developing salt-tolerant crop varieties using different breeding approaches. This review highlights the interlinking of plant morpho-physiological, molecular, biochemical, and genetic approaches to produce salt-tolerant plant species. Most of the research emphasizes the significance of plant growth-promoting rhizobacteria in protecting plants from biotic and abiotic stressors. Plant growth, survival, and yield can be stabilized by utilizing this knowledge using different breeding and agronomical techniques. This information marks existing research areas and future gaps that require more attention to reveal new salt tolerance determinants in plants—in the future, creating genetically modified plants could help increase crop growth and the toleration of saline environments.
Enterococcus raffinosus, Enterococcus durans and Enterococcus avium Isolated from a Tertiary Care Hospital in Romania—Retrospective Study and Brief Review
Authors: Toc Dan Alexandru , Pandrea Stanca Lucia , Botan Alexandru , Mihaila Razvan Marian , Costache Carmen Anca , Colosi Ioana Alina , Junie Lia Monica
Published: April 2022

(1) Background: This paper aims to provide a description of non-faecalis non-faecium enterococci isolated from a tertiary care hospital in Romania and to briefly review the existing literature regarding the involvement of Enterococcus raffinosus, Enterococcus durans and Enterococcus avium in human infections and their antimicrobial resistance patterns; (2) Methods: We retrospectively analyzed all Enteroccocus species isolated from the “Prof. Dr. O. Fodor” Regional Institute of Gastroenterology and Hepatology from Cluj-Napoca during one year focusing on non-faecalis non-faecium Enterococci. A brief review of the literature was performed using case reports involving Enterococcus raffinosus, Enterococcus durans and Enterococcus avium; (3) Results: Only 58 out of 658 Enteroccocus isolates were non-faecalis non-faecium and met the inclusion criteria. These species were isolated more often (p < 0.05) from the surgical ward from mixed etiology infections with E. coli. In our review, we included 39 case reports involving E. raffinosus, E. durans and E. avium; (4) Conclusions: Isolation of non-faecalis non-faecium enterococci displays an emerging trend with crucial healthcare consequences. Based on the analysis of the case reports, E. avium seems to be involved more often in neurological infections, E. durans in endocarditis, while E. raffinosus displays a more heterogenous distribution.
Traumatic Brain Injury Characteristics Predictive of Subsequent Sleep-Wake Disturbances in Pediatric Patients
Authors: Gerald Brittany , Ortiz J. Bryce , Green Tabitha R. F. , Brown S. Danielle , Adelson P. David , Murphy Sean M. , Rowe Rachel K.
Published: April 2022

The objective of this study was to determine the prevalence of sleep-wake disturbances (SWD) following pediatric traumatic brain injury (TBI), and to examine characteristics of TBI and patient demographics that might be predictive of subsequent SWD development. This single-institution retrospective study included patients diagnosed with a TBI during 2008–2019 who also had a subsequent diagnosis of an SWD. Data were collected using ICD-9/10 codes for 207 patients and included the following: age at initial TBI, gender, TBI severity, number of TBIs diagnosed prior to SWD diagnosis, type of SWD, and time from initial TBI to SWD diagnosis. Multinomial logit and negative-binomial models were fit to investigate whether the multiple types of SWD and the time to onset of SWD following TBI could be predicted by patient variables. Distributions of SWD diagnosed after TBI were similar between genders. The probability of insomnia increased with increasing patient age. The probability of ‘difficulty sleeping’ was highest in 7–9 year-old TBI patients. Older TBI patients had shorter time to SWD onset than younger patients. Patients with severe TBI had the shortest time to SWD onset, whereas patients with mild or moderate TBI had comparable times to SWD onset. Multiple TBI characteristics and patient demographics were predictive of a subsequent SWD diagnosis in the pediatric population. This is an important step toward increasing education among providers, parents, and patients about the risk of developing SWD following TBI.
Metformin in Differentiated Thyroid Cancer: Molecular Pathways and Its Clinical Implications
Authors: García-Sáenz Manuel , Lobaton-Ginsberg Miry , Ferreira-Hermosillo Aldo
Published: April 2022

Metformin is a synthetic biguanide that improves insulin sensitivity and reduces hepatic gluconeogenesis. Aside being the first-line therapy for Type 2 Diabetes (T2D), many pleiotropic effects have been discovered in recent years, such as its capacity to reduce cancer risk and tumorigenesis. Although widely studied, the effect of metformin on thyroid cancer remains controversial. Potential mechanisms for its growth inhibitory effects have been elucidated in various preclinical studies that involved pathways related to adenosine mono-phosphate-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR), mitochondrial glycerophosphate dehydrogenase (mGPDH), and the nuclear factor κB (NF-κB). Hyperinsulinemia increases cell glucose uptake and oxidative stress, and promotes thyroid cell growth, leading to hyperproliferation, carcinogenesis, and the development of malignant tumors. Furthermore, it has also been related to thyroid nodules size in nodular disease, as well as tumoral size in patients with thyroid cancer. Several clinical studies concluded that metformin might have an important role as an adjuvant therapy to reduce the growth of benign and malignant thyroid neoplasms. This suggests that metformin might be useful for patients with differentiated or poorly differentiated thyroid cancer and metabolic diseases such as insulin resistance or diabetes.
Hypoxia Alters the Proteome Profile and Enhances the Angiogenic Potential of Dental Pulp Stem Cell-Derived Exosomes
Authors: Li Baoyu , Xian Xuehong , Lin Xinwei , Huang Luo , Liang Ailin , Jiang Hongwei , Gong Qimei
Published: April 2022

Dental pulp stem cells (DPSCs) and their exosomes (Exos) are effective treatments for regenerative medicine. Hypoxia was confirmed to improve the angiogenic potential of stem cells. However, the angiogenic effect and mechanism of hypoxia-preconditioned DPSC-Exos are poorly understood. We isolated exosomes from DPSCs under normoxia (Nor-Exos) and hypoxia (Hypo-Exos) and added them to human umbilical vein endothelial cells (HUVECs). HUVEC proliferation, migration and angiogenic capacity were assessed by CCK-8, transwell, tube formation assays, qRT-PCR and Western blot. iTRAQ-based proteomics and bioinformatic analysis were performed to investigate proteome profile differences between Nor-Exos and Hypo-Exos. Western blot, immunofluorescence and immunohistochemistry were used to detect the expression of lysyl oxidase-like 2 (LOXL2) in vitro and in vivo. Finally, we silenced LOXL2 in HUVECs and rescued tube formation with Hypo-Exos. Hypo-Exos enhanced HUVEC proliferation, migration and tube formation in vitro superior to Nor-Exos. The proteomics analysis identified 79 proteins with significantly different expression in Hypo-Exos, among which LOXL2 was verified as being upregulated in hypoxia-preconditioned DPSCs, Hypo-Exos, and inflamed dental pulp. Hypo-Exos partially rescued the inhibitory influence of LOXL2 silence on HUVEC tube formation. In conclusion, hypoxia enhanced the angiogenic potential of DPSCs-Exos and partially altered their proteome profile. LOXL2 is likely involved in Hypo-Exos mediated angiogenesis.
The Ribosome Is the Ultimate Receptor for Trypsin Modulating Oostatic Factor (TMOF)
Authors: Borovsky Dov , Rougé Pierre , Shatters Robert G.
Published: April 2022

Aedes aegypti Trypsin Modulating Oostatic Factor (AeaTMOF). a mosquito decapeptide that controls trypsin biosynthesis in female and larval mosquitoes. enters the gut epithelial cells of female mosquitoes using ABC-tmfA receptor/importer. To study the ultimate targeted receptor after AeaTMOF enters the cell, AeaTMOF was incubated in vitro with either Escherichia coli or Spodoptera frugiperda protein-expressing extracts containing 70S and 80S ribosomes, respectively. The effect of AeaTMOF on luciferase biosynthesis in vitro using 70S ribosomes was compared with that of oncocin112 (1–13), a ribosome-binding antibacterial peptide. The IC50 of 1 μM and 2 μM, respectively, for both peptides was determined. Incubation with a protein-expressing system and S. frugiperda 80S ribosomes determined an IC50 of 1.8 μM for Aedes aegypti larval late trypsin biosynthesis. Incubation of purified E. coli ribosome with increasing concentration of AeaTMOF shows that the binding of AeaTMOF to the bacterial ribosome exhibits a high affinity (KD = 23 ± 3.4 nM, Bmax = 0.553 ± 0.023 pmol/μg ribosome and Kassoc = 4.3 × 107 M−1). Molecular modeling and docking experiments show that AeaTMOF binds bacterial and Drosophila ribosome (50S and 60S, respectively) at the entrance of the ribosome exit tunnel, blocking the tRNA entrance and preventing protein biosynthesis. Recombinant E. coli cells that express only ABC-tmfA importer are inhibited by AeaTMOF but not by oncocin112 (1–13). These results suggest that the ribosome is the ultimate targeted receptor of AeaTMOF.
Effects of Glucose Metabolism, Lipid Metabolism, and Glutamine Metabolism on Tumor Microenvironment and Clinical Implications
Authors: Zhu Longfei , Zhu Xuanyu , Wu Yan
Published: April 2022

In recent years, an increasingly more in depth understanding of tumor metabolism in tumorigenesis, tumor growth, metastasis, and prognosis has been achieved. The broad heterogeneity in tumor tissue is the critical factor affecting the outcome of tumor treatment. Metabolic heterogeneity is not only found in tumor cells but also in their surrounding immune and stromal cells; for example, many suppressor cells, such as tumor-associated macrophages (TAMs), myeloid-derived suppressor cells (MDSCs), and tumor-associated T-lymphocytes. Abnormalities in metabolism often lead to short survival or resistance to antitumor therapy, e.g., chemotherapy, radiotherapy, targeted therapy, and immunotherapy. Using the metabolic characteristics of the tumor microenvironment to identify and treat cancer has become a great research hotspot. This review systematically addresses the impacts of metabolism on tumor cells and effector cells and represents recent research advances of metabolic effects on other cells in the tumor microenvironment. Finally, we introduce some applications of metabolic features in clinical oncology.
Potential Effects of Natural H2S-Donors in Hypertension Management
Authors: Piragine Eugenia , Citi Valentina , Lawson Kim , Calderone Vincenzo , Martelli Alma
Published: April 2022

After the discovery of hydrogen sulfide (H2S) in the central nervous system by Abe and Kimura in 1996, the physiopathological role of H2S has been widely investigated in several systems such as the cardiovascular. In particular, H2S plays a pivotal role in the control of vascular tone, exhibiting mechanisms of action able to induce vasodilation: for instance, activation of potassium channels (KATP and Kv7) and inhibition of 5-phosphodiesterase (5-PDE). These findings paved the way for the research of natural and synthetic exogenous H2S-donors (i.e., molecules able to release H2S) in order to have new tools for the management of hypertension. In this scenario, some natural molecules derived from Alliaceae (i.e., garlic) and Brassicaceae (i.e., rocket or broccoli) botanical families show the profile of slow H2S-donors able to mimic the endogenous production of this gasotransmitter and therefore can be viewed as interesting potential tools for management of hypertension or pre-hypertension. In this article, the preclinical and clinical impacts of these natural H2S-donors on hypertension and vascular integrity have been reviewed in order to give a complete panorama of their potential use for the management of hypertension and related vascular diseases.
“Malancha” [Alternanthera philoxeroides (Mart.) Griseb.]: A Potential Therapeutic Option against Viral Diseases
Authors: Nahar Lutfun , Nath Sushmita , Sarker Satyajit D.
Published: April 2022

Alternanthera philoxeroides (Mart.) Griseb., commonly known as “Alligator weed” in English, and “Malancha” in Bengali, is a leafy vegetable from the family Amaranthaceae A. L. de Jussieu. This species is native to China, particularly to the provinces around the Yangtze River, other Far East and South-East Asian countries, and countries from other continents (e.g., South America). This plant also grows in certain areas in Australia, New Zealand, and the USA. While in Bangladesh the leaves of this plant are consumed as a vegetable, in China, this plant has been used widely as a traditional remedy for the treatment of various viral diseases (e.g., measles, influenza, and haemorrhagic fever). Flavonoids and saponins are the two largest groups of phytochemicals produced by this plant, and the antiviral property of this plant and its compounds has been studied extensively. This review article reviews all published literature on this plant and critically appraises its phytochemical profile linking to biomolecular interactions and therapeutic potential, particularly, against viral diseases.