bluuebunny/crossref_metadata_2025 huggingface dataset:
Robust Spectrum Sensing Detector Based on MIMO Cognitive Radios with Non-Perfect Channel Gain
Authors: Al-Amidie Muthana , Al-Asadi Ahmed , Humaidi Amjad J. , Al-Dujaili Ayad , Alzubaidi Laith , Farhan Laith , Fadhel Mohammed A. , McGarvey Ronald G. , Islam Naz E.
Published: February 2021

The spectrum has increasingly become occupied by various wireless technologies. For this reason, the spectrum has become a scarce resource. In prior work, the authors have addressed the spectrum sensing problem by using multi-input and multi-output (MIMO) in cognitive radio systems. We considered the detection and estimation framework for MIMO cognitive network where the noise covariance matrix is unknown with perfect channel state information. In this study, we propose a generalized likelihood ratio test (GLRT) for the spectrum sensing problem in cognitive radio where the noise covariance matrix is unknown with non-perfect channel state information. Two scenarios are examined in this study: (i) in the first scenario, the sub-optimal solution of the worst case of the system’s performance is considered; (ii) in the second scenario, we present a robust detector for the MIMO spectrum sensing problem. For both scenarios, the Bayesian approach with a generalized likelihood ratio test based on the binary hypothesis problem is used. From the results, it can be seen that our approach provides the best performance in the spectrum sensing problem under specified assumptions. The simulation results also demonstrate that our approach significantly outperforms other state-of-the-art spectrum sensing detectors when the channel uncertainty is addressed.
Two Stage Continuous Gesture Recognition Based on Deep Learning
Authors: Wang Huogen
Published: February 2021

The paper proposes an effective continuous gesture recognition method, which includes two modules: segmentation and recognition. In the segmentation module, the video frames are divided into gesture frames and transitional frames by using the information of hand motion and appearance, and continuous gesture sequences are segmented into isolated sequences. In the recognition module, our method exploits the spatiotemporal information embedded in RGB and depth sequences. For the RGB modality, our method adopts Convolutional Long Short-Term Memory Networks to learn long-term spatiotemporal features from short-term spatiotemporal features obtained from a 3D convolutional neural network. For the depth modality, our method converts a sequence into Dynamic Images and Motion Dynamic Images through weighted rank pooling and feed them into Convolutional Neural Networks, respectively. Our method has been evaluated on both ChaLearn LAP Large-scale Continuous Gesture Dataset and Montalbano Gesture Dataset and achieved state-of-the-art performance.
A Study of Overripe Seed Byproducts from Sun-Dried Grapes by Dispersive Raman Spectroscopy
Authors: Rivero Francisco J. , Ciaccheri Leonardo , González-Miret M. Lourdes , Rodríguez-Pulido Francisco J. , Mencaglia Andrea A. , Heredia Francisco J. , Mignani Anna G. , Gordillo Belén
Published: February 2021

Overripe seeds from sun-dried grapes submitted to postharvest dehydration constitute a scarcely investigated class of vinification byproduct with limited reports on their phenolic composition and industrial applications. In this study, Raman spectroscopy was applied to characterize a selection of overripe seed byproducts from different white grapes (cv. Moscatel, cv. Pedro Ximénez and cv. Zalema) submitted to postharvest sun drying. The Raman measurements were taken using a 1064 nm excitation laser in order to mitigate the fluorescent effect and the dispersive detection scheme allowed a compactness of the optical system. Spectroscopic data were processed by a principal component analysis to reduce the dimensionality and partner recognition. The evolution of the Raman spectrum during the overripening process was compared with the phenolic composition of grape seeds, which was determined by rapid resolution liquid chromatography/mass spectrometry (RRLC/MS). A multivariate processing of the spectroscopic data allowed the classification of overripe seeds according to the grape variety and the monitoring of stages of the postharvest sun drying process.
Functionalization of Enzymatically Treated Apple Pomace from Juice Production by Extrusion Processing
Authors: Schmid Vera , Trabert Antje , Keller Judith (Schäfer) , Bunzel Mirko , Karbstein Heike P. , Emin M. Azad
Published: February 2021

Food by-products can be used as natural and sustainable food ingredients. However, a modification is needed to improve the technofunctional properties according to the specific needs of designated applications. A lab-scale twin-screw extruder was used to process enzymatically treated apple pomace from commercial fruit juice production. To vary the range of the thermomechanical treatment, various screw speeds (200, 600, 1000 min−1), and screw configurations were applied to the raw material. Detailed chemical and functional analyses were performed to develop a comprehensive understanding of the impact of the extrusion processing on apple pomace composition and technofunctional properties as well as structures of individual polymers. Extrusion at moderate thermomechanical conditions increased the water absorption, swelling, and viscosity of the material. An increase in thermomechanical stress resulted in a higher water solubility index, but negatively affected the water absorption index, viscosity, and swelling. Scanning electron microscopy showed an extrusion-processing-related disruption of the cell wall. Dietary fiber analysis revealed an increase of soluble dietary fiber from 12.6 to 17.2 g/100 g dry matter at maximum thermo-mechanical treatment. Dietary fiber polysaccharide analysis demonstrated compositional changes, mainly in the insoluble dietary fiber fraction. In short, pectin polysaccharides seem to be susceptible to thermo-mechanical stress, especially arabinans as neutral side chains of rhamnogalacturonan I.
Demographic, Anthropometric and Food Behavior Data towards Healthy Eating in Romania
Authors: Bacârea Anca , Bacârea Vladimir Constantin , Cînpeanu Cristina , Teodorescu Claudiu , Seni Ana Gabriela , Guiné Raquel P. F. , Tarcea Monica
Published: February 2021

Background: Each country has specific social, cultural, and economic characteristics regarding the motivations for improving health. The aim of this study was to evaluate demographic characteristics, anthropometric data, and elements related to food behavior and health, as well as Romanians’ motivations towards healthy eating. Methods: This is a descriptive cross-sectional questionnaire based study enrolling 751 Romanian participants, which was carried out in in 2017–2018. Results: We obtained a positive correlation between age and Body Mass Index, and this was maintained also when we analyzed the two genders separately, being, however, even stronger for women. The number of hours/day spent watching TV or in front of the computer was positively correlated with both age and BMI. In general, with aging, there is an increasing concern regarding the practice of a healthy diet. The higher education level was significantly associated with healthier choices. Conclusions: The study of the three dietary dimensions, food properties, health attitudes, and dietary behavior, vis-à-vis various disorders revealed that the group most concerned of their diet was those who suffered from cardiovascular disorders.
Neuropsychological Study in Patients with Spinal Cord Injuries
Authors: Molina-Gallego Brígida , Gómez-Cantarino Sagrario , Ugarte-Gurrutxaga María Idoia , Molina-Gallego Laura , Mordillo-Mateos Laura
Published: February 2021

The present investigation was designed to determinate the nature, pattern, and extent of cognitive deficits in a group of participants with subacute and chronic spinal cord injury (SCI). Methods: A cross-sectional study was conducted in both patients with subacute and chronic SCI. Different cognitive functions were evaluated through a neuropsychological protocol designed for this purpose, taking into account the patient’s emotional state. Results: A total of 100 patients suffering a spinal cord injury were evaluated. There were no differences between the two groups when age, sex, level of education, and region of origin were studied. The chronic injured patients obtained lower scores in the neuropsychological evaluation protocol respective to the subacute injured patients. Conclusions: Subjects with chronic spinal cord injury presented a cognitive profile that differed greatly in the number of altered cognitive functions as well as in their magnitude from the subacute spinal cord injured patient profile. Moreover, cognitive dysfunction may be important beyond the end of the first stage of rehabilitation as it can affect an individual’s quality of life and possible integration in society.
The Effect of Simulation Nursing Education Using the Outcome-Present State-Test Model on Clinical Reasoning, the Problem-Solving Process, Self-Efficacy, and Clinical Competency in Korean Nursing Students
Authors: Seo Yon Hee , Eom Mi Ran
Published: February 2021

The purpose of this study was to assess the effect of a simulation nursing education program in terms of clinical reasoning, problem-solving process, self-efficacy, and clinical competency using the Outcome-Present State-Test (OPT) model in nursing students. The participants comprised 45 undergraduate nursing students recruited from two universities in Korea. The number of nursing students assigned to the experimental group and control group were 25 and 20, respectively. For a period of two weeks, the experimental group received a simulation nursing education program using the OPT model, while the control group received a traditional clinical practicum. The data were analyzed using prior homogeneity tests (Fisher’s exact test and paired t-test); ANCOVA was performed to investigate the differences in dependent variables between the two groups. There was a significant improvement in clinical reasoning (F = 10.59, p = 0.002), problem-solving process (F = 30.92, p < 0.001), and self-efficacy (F = 36.03, p < 0.001) in the experimental group as compared to the control group (F = 10.59, p = 0.002). Moreover, the experimental group showed significantly higher scores in clinical competency than the control group (F = 11.07, p = 0.002). This study demonstrates that the simulation nursing education program using the OPT model for undergraduate students is very effective in promoting clinical reasoning, problem-solving processes, self-efficacy, and clinical competency.
Editorial of Special Issue “Protein Post-Translational Modifications in Signal Transduction and Diseases”
Authors: D’Amore Claudio , Salvi Mauro
Published: February 2021

The making of a protein is based on the combination of 20 different monomers (22 considering selenocysteine and pyrrolysine, the latest present only in some archaea and bacteria) giving the possibility of building a variety of structures from the simplest to the most complex, rigid or highly dynamic, and suited to carry out a wide range of structural and functional roles [...]
Effects of Non-Thermal Plasma on Yeast Saccharomyces cerevisiae
Authors: Polčic Peter , Machala Zdenko
Published: February 2021

Cold plasmas generated by various electrical discharges can affect cell physiology or induce cell damage that may often result in the loss of viability. Many cold plasma-based technologies have emerged in recent years that are aimed at manipulating the cells within various environments or tissues. These include inactivation of microorganisms for the purpose of sterilization, food processing, induction of seeds germination, but also the treatment of cells in the therapy. Mechanisms that underlie the plasma-cell interactions are, however, still poorly understood. Dissection of cellular pathways or structures affected by plasma using simple eukaryotic models is therefore desirable. Yeast Saccharomyces cerevisiae is a traditional model organism with unprecedented impact on our knowledge of processes in eukaryotic cells. As such, it had been also employed in studies of plasma-cell interactions. This review focuses on the effects of cold plasma on yeast cells.
Ophthalmic Screening in Patients with Coronavirus Disease 2019: A Prospective Cohort Study
Authors: Papazoglou Anthia , Conen Anna , Haubitz Sebastian , Tschopp Markus , Guignard Viviane J. , Menke Marcel N. , Enz Tim J.
Published: February 2021

Postmortem pathological examinations, animal studies, and anecdotal reports suggest that coronavirus disease 2019 (COVID-19) could potentially affect intraocular tissue. However, published evidence is scarce and conflicting. In our study, we screened 100 eyes of 50 patients hospitalized for COVID-19. Relevant medical and ophthalmological history was assessed as well as symptoms, laboratory results, specific treatments, clinical course, and outcome. Ophthalmic exams including assessment of best corrected visual acuity (BCVA), intraocular pressure (IOP), color perception, ocular motility, ophthalmoscopy as well as optical coherence tomography (OCT) of the macula and the optic disc was performed at hospital admission and 29 to 192 days later. Of the 50 patients included, 14 (28%) were female. Median age was 64.5 (range 29–90) years. COVID-19 severity was mild in 15 (30%), severe in 30 (60%), and critical in five cases (10%). At baseline, median BCVA was 0.1 (0–1.8) Logarithm of the Minimum Angle of Resolution (LogMAR) and median IOP was 16 (8–22) mmHg. At follow-up, no relevant changes in BCVA and IOP were documented. No signs of active intraocular inflammation or optic nerve affection were found and OCT findings were widely stable during the observation period. Our findings suggest that COVID-19 does not regularly affect intraocular tissue.
Artificial Nourishments Effects on Longshore Sediments Transport
Authors: Ferreira Ana Margarida , Coelho Carlos
Published: February 2021

Serious erosion problems related to significant negative sediments budgets in the coastal systems are referred worldwide. Artificial nourishments are a coastal erosion mitigation strategy that allow for a decrease in those negative budgets by adding sediment to the coastal system. Thus, it is essential to understand and adequately model the shoreline response after a nourishment operation, in order to support the definition of the best intervention scenarios. The main goal of this work was to study the artificial nourishment effects on the longshore sediment transport and consequently on the morphological evolution at the intervention site and nearby areas, in a time horizon of 5 years. The longshore transport of the nourished sediments was evaluated, aiming to contribute to the evaluation of the sediment’s permanence at the deposition site and the frequency required for new nourishments. The shoreline evolution numerical long-term configuration (LTC) model was applied in order to evaluate the spatial and temporal distribution of the nourished sediments along the coast, considering different types of beaches and incident wave climates. The adopted approach is generic and supported by simple numerical models, which can be useful for preliminary site-specific evaluations. The results show that the nourishment impact is mainly observed nearby the intervention site. It is highlighted that higher longshore sediment transport rates are associated with more energetic wave climates, but not necessarily with incident waves more oblique to the shoreline.
In-Situ Variability of DOM in Relation with Biogeochemical and Physical Parameters in December 2017 in Laucala Bay (Fiji Islands) after a Strong Rain Event
Authors: Koliyavu Timoci , Martias Chloe , Singh Awnesh , Mounier Stéphane , Gérard Philippe , Dupouy Cecile
Published: February 2021

Heavy rain events alter the biogeochemical outflows, affects water quality and ecosystem health within the coastal waters of small Pacific Islands. We characterized snapshots of the optical fingerprints of dissolved organic matter (DOM) sources together with the select nutrients, biogeochemical and physical variables for 10 stations in December 2017 in Laucala Bay, Fiji Islands. DOM absorption coefficients and fluorescence components were determined via spectrofluorometry and Parallel Factor Analysis identifying four components: Type M, two terrestrial (humic, fulvic) components, and a protein component linked to marine biological activity. Associations of DOM together with climate variables and the other tested variables were determined via principal component, hierarchical cluster, and cross-correlation (Pearson) analysis. All component s (together with most tested variables) displayed higher values (plumes) at the southwest coast consistent with surface currents outflow during the wet season. Type M component associated with two allochthonous fluorescent components signaling anthropogenic forcings via riverine outflows. Terrigenous inputs association with autochthonous chromophoric dissolved organic matter (CDOM) is indicative of tidal mixing, dilution, and bottom resuspension processes. Positive correlations of dissolved organic carbon (DOC) with nutrients (NOx, PO4) elucidates DOM being utilized as energy sources. The positive correlation of DON with nutrients (NOx, PO4, Si(OH)4) reflects the role of DON as a nutrient source consistent with chlorophyll plume formation.
Spatial Distributions of Surface Sedimentary Organics and Sediment Profile Image Characteristics in a High-Energy Temperate Marine RiOMar: The West Gironde Mud Patch
Authors: Lamarque Bastien , Deflandre Bruno , Galindo Dalto Adriana , Schmidt Sabine , Romero-Ramirez Alicia , Garabetian Frédéric , Dubosq Nicolas , Diaz Mélanie , Grasso Florent , Sottolichio Aldo , Bernard Guillaume , Gillet Hervé , Cordier Marie-Ange , Poirier Dominique , Lebleu Pascal , Derriennic Hervé , Danilo Martin , Murilo Barboza Tenório Márcio , Grémare Antoine
Published: February 2021

The spatial distributions of (1) surface sediment characteristics (D0.5, Sediment Surface Area (SSA), Particulate Organic Carbon (POC), Chlorophyll-a (Chl-a), Phaeophytin-a (Phaeo-a), Total and Enzymatically Hydrolyzable Amino Acids (THAA, EHAA), δ13C) and (2) sediment profile image (apparent Redox Potential Discontinuity (aRPD), numbers and depths of biological traces) characteristics were quantified based on the sampling of 32 stations located within the West Gironde Mud Patch (Bay of Biscay, NE Atlantic) in view of (1) assessing the spatial structuration of a temperate river-dominated ocean margin located in a high-energy area, (2) disentangling the impacts of hydrodynamics and bottom trawling on this structuration, and (3) comparing the West Gironde Mud Patch with the Rhône River Prodelta (located in a low-energy area). Results support the subdivision of the West Gironde Mud Patch in a proximal and a distal part and show (1) the existence of depth gradients in surface sedimentary organics characteristics and bioturbation within the distal part; (2) no evidence for a significant effect of bottom trawling, as opposed to Bottom Shear Stress, on the West Gironde Mud Patch spatial structuration; and (3) major discrepancies between spatial structuration in the West Gironde Mud Patch and the Rhône River Prodelta, which were attributed to differences in tidal regimes, sedimentation processes, and local hydrodynamics, which is in agreement with current river-dominated ocean margin typologies.
Tools for Assessing Translation in Cryptococcus neoformans
Authors: Knowles Corey M. , McIntyre Kelcy M. , Panepinto John C.
Published: February 2021

Cryptococcus neoformans is a ubiquitous environmental fungus capable of establishing an infection in a human host. Rapid changes in environments and exposure to the host immune system results in a significant amount of cellular stress, which is effectively combated at the level of translatome reprogramming. Repression of translation following stress allows for the specific reallocation of limited resources. Understanding the mechanisms involved in regulating translation in C. neoformans during host infection is critical in the development of new antifungal drugs. In this review, we discuss the main tools available for assessing changes in translation state and translational output during cellular stress.
Consideration of Distinguishing Design Features of Gas-Turbine and Gas-Reciprocating Units in Design of Emergency Control Systems
Authors: Ilyushin Pavel , Kulikov Aleksandr , Suslov Konstantin , Filippov Sergey
Published: February 2021

Modern gas-turbine units (GTUs) and gas-reciprocating units (GRUs) have found a wide use at power plants, including distributed generation facilities, running on gaseous fuel. The design features of these generating units have a considerable effect on the nature and parameters of transient processes due to emergency disturbances in the adjacent network. The study shows that single-shaft gas-turbine and gas-reciprocating units do not allow even short-term considerable frequency drops. These schemes and operating conditions arise due to emergency active power shortages when the connection between the power plant and the power system weakens due to repair conditions or islanded operation. The paper presents the results of transient process calculations for operating power plants (distributed generation facilities), which make it possible to identify the unfavorable properties of GTUs and GRUs. The results show that two-shaft (three-shaft) GTUs and GRUs can switch to out-of-step conditions even when short-circuits in the adjacent network are cleared with high-speed relay protection devices. The features of out-of-step conditions and the admissibility of their short-term duration for the spontaneous restoration of generators’ synchronization are considered. The findings suggest that considering the fundamental design features of generating units provides informed technical decisions on equipping power plants (distributed generation (DG) facilities) and the adjacent network with efficient emergency control systems.
A New Approach for Approximate Solution of ADE: Physical-Based Modeling of Carriers in Doping Region
Authors: Hernandez-Gonzalez Leobardo , Ramirez-Hernandez Jazmin , Ulises Juarez-Sandoval Oswaldo , Olivares-Robles Miguel Angel , Sanchez Ramon Blanco , Gibert Delgado Rosario del Pilar
Published: February 2021

The electric behavior in semiconductor devices is the result of the electric carriers’ injection and evacuation in the low doping region, N-. The carrier’s dynamic is determined by the ambipolar diffusion equation (ADE), which involves the main physical phenomena in the low doping region. The ADE does not have a direct analytic solution since it is a spatio-temporal second-order differential equation. The numerical solution is the most used, but is inadequate to be integrated into commercial electric circuit simulators. In this paper, an empiric approximation is proposed as the solution of the ADE. The proposed solution was validated using the final equations that were implemented in a simulator; the results were compared with the experimental results in each phase, obtaining a similarity in the current waveforms. Finally, an advantage of the proposed methodology is that the final expressions obtained can be easily implemented in commercial simulators.
A Multicriteria Goal Programming Model for Ranking Universities
Authors: García Fernando , Guijarro Francisco , Oliver Javier
Published: February 2021

This paper proposes the use of a goal programming model for the objective ranking of universities. This methodology has been successfully used in other areas to analyze the performance of firms by focusing on two opposite approaches: (a) one favouring those performance variables that are aligned with the central tendency of the majority of the variables used in the measurement of the performance, and (b) an alternative one that favours those different, singular, or independent performance variables. Our results are compared with the ranking proposed by two popular World University Rankings, and some insightful differences are outlined. We show how some top-performing universities occupy the best positions regardless of the approach followed by the goal programming model, hence confirming their leadership. In addition, our proposal allows for an objective quantification of the importance of each variable in the performance of universities, which could be of great interest to decision-makers.
Local Well-Posedness for Free Boundary Problem of Viscous Incompressible Magnetohydrodynamics
Authors: Oishi Kenta , Shibata Yoshihiro
Published: February 2021

In this paper, we consider the motion of incompressible magnetohydrodynamics (MHD) with resistivity in a domain bounded by a free surface. An electromagnetic field generated by some currents in an external domain keeps an MHD flow in a bounded domain. On the free surface, free boundary conditions for MHD flow and transmission conditions for electromagnetic fields are imposed. We proved the local well-posedness in the general setting of domains from a mathematical point of view. The solutions are obtained in an anisotropic space Hp1((0,T),Hq1)∩Lp((0,T),Hq3) for the velocity field and in an anisotropic space Hp1((0,T),Lq)∩Lp((0,T),Hq2) for the magnetic fields with 2<p<∞, N<q<∞ and 2/p+N/q<1. To prove our main result, we used the Lp-Lq maximal regularity theorem for the Stokes equations with free boundary conditions and for the magnetic field equations with transmission conditions, which have been obtained by Frolova and the second author.
Integrated Survival Analysis and Frequent Pattern Mining for Course Failure-Based Prediction of Student Dropout
Authors: Csalódi Róbert , Abonyi János
Published: February 2021

A data-driven method to identify frequent sets of course failures that students should avoid in order to minimize the likelihood of their dropping out from their university training is proposed. The overall probability distribution of the dropout is determined by survival analysis. This result can only describe the mean dropout rate of the undergraduates. However, due to the failure of different courses, the chances of dropout can be highly varied, so the traditional survival model should be extended with event analysis. The study paths of students are represented as events in relation to the lack of completing the required subjects for every semester. Frequent patterns of backlogs are discovered by the mining of frequent sets of these events. The prediction of dropout is personalised by classifying the success of the transitions between the semesters. Based on the explored frequent item sets and classifiers, association rules are formed providing the estimates of the success of the continuation of the studies in the form of confidence metrics. The results can be used to identify critical study paths and courses. Furthermore, based on the patterns of individual uncompleted subjects, it is suitable to predict the chance of continuation in every semester. The analysis of the critical study paths can be used to design personalised actions minimizing the risk of dropout, or to redesign the curriculum aiming the reduction in the dropout rate. The applicability of the method is demonstrated based on the analysis of the progress of chemical engineering students at the University of Pannonia in Hungary. The method is suitable for the examination of more general problems assuming the occurrence of a set of events whose combinations may trigger a set of critical events.
Existence and Concentration Behavior of Solutions of the Critical Schrödinger–Poisson Equation in R3
Authors: Wang Jichao , Yu Ting
Published: February 2021

In this paper, we study the singularly perturbed problem for the Schrödinger–Poisson equation with critical growth. When the perturbed coefficient is small, we establish the relationship between the number of solutions and the profiles of the coefficients. Furthermore, without any restriction on the perturbed coefficient, we obtain a different concentration phenomenon. Besides, we obtain an existence result.
A 2D Membrane MEMS Device Model with Fringing Field: Curvature-Dependent Electrostatic Field and Optimal Control
Authors: Di Barba Paolo , Fattorusso Luisa , Versaci Mario
Published: February 2021

An important problem in membrane micro-electric-mechanical-system (MEMS) modeling is the fringing-field phenomenon, of which the main effect consists of force-line deformation of electrostatic field E near the edges of the plates, producing the anomalous deformation of the membrane when external voltage V is applied. In the framework of a 2D circular membrane MEMS, representing the fringing-field effect depending on |∇u|2 with the u profile of the membrane, and since strong E produces strong deformation of the membrane, we consider |E| proportional to the mean curvature of the membrane, obtaining a new nonlinear second-order differential model without explicit singularities. In this paper, the main purpose was the analytical study of this model, obtaining an algebraic condition ensuring the existence of at least one solution for it that depends on both the electromechanical properties of the material constituting the membrane and the positive parameter δ that weighs the terms |∇u|2. However, even if the the study of the model did not ensure the uniqueness of the solution, it made it possible to achieve the goal of finding a stable equilibrium position. Moreover, a range of admissible values of V were obtained in order, on the one hand, to win the mechanical inertia of the membrane and, on the other hand, to ensure that the membrane did not touch the upper disk of the device. Lastly, some optimal control conditions based on the variation of potential energy are presented and discussed.
Out-of-Control Multivariate Patterns Recognition Using D2 and SVM: A Study Case for GMAW
Authors: Chiñas-Sanchez Pamela , Lopez-Juarez Ismael , Vazquez-Lopez Jose Antonio , Navarro-Gonzalez Jose Luis , Hernandez-Lopez Aidee
Published: February 2021

Industrial processes seek to improve their quality control, including new technologies and satisfying requirements for globalised markets. In this paper, we present an innovative method based on Multivariate Pattern Recognition (MVPR) and process monitoring in a real-world study case. By identifying a distinctive out-of-control multivariate pattern using the Support Vector Machines (SVM) and the Mahalanobis Distance D2 it is possible to infer the variables that disturbed the process; hence, possible faults can be predicted knowing the state of the process. The method is based on our previous work, and in this paper we present the method application for an automated process, namely, the robotic Gas Metal Arc Welding (GMAW). Results from the application indicate an overall accuracy up to 88.8%, which demonstrates the effectiveness of the method, which can also be used in other MVPR tasks.
Microbial Hydroxysteroid Dehydrogenases: From Alpha to Omega
Authors: Doden Heidi L. , Ridlon Jason M.
Published: February 2021

Bile acids (BAs) and glucocorticoids are steroid hormones derived from cholesterol that are important signaling molecules in humans and other vertebrates. Hydroxysteroid dehydrogenases (HSDHs) are encoded both by the host and by their resident gut microbiota, and they reversibly convert steroid hydroxyl groups to keto groups. Pairs of HSDHs can reversibly epimerize steroids from α-hydroxy conformations to β-hydroxy, or β-hydroxy to ω-hydroxy in the case of ω-muricholic acid. These reactions often result in products with drastically different physicochemical properties than their precursors, which can result in steroids being activators or inhibitors of host receptors, can affect solubility in fecal water, and can modulate toxicity. Microbial HSDHs modulate sterols associated with diseases such as colorectal cancer, liver cancer, prostate cancer, and polycystic ovary syndrome. Although the role of microbial HSDHs is not yet fully elucidated, they may have therapeutic potential as steroid pool modulators or druggable targets in the future. In this review, we explore metabolism of BAs and glucocorticoids with a focus on biotransformation by microbial HSDHs.
The Screening of Potassium- and Phosphate-Solubilizing Actinobacteria and the Assessment of Their Ability to Promote Wheat Growth Parameters
Authors: Boubekri Kenza , Soumare Abdoulaye , Mardad Ilham , Lyamlouli Karim , Hafidi Mohamed , Ouhdouch Yedir , Kouisni Lamfeddal
Published: February 2021

Soil fertility and plant nutrition require an adequate management of essential macronutrients such as potassium (K) and phosphorus (P), which are mandatory for plant development. Bioleaching of K and P bearing minerals improves their chemical weathering and increases the performance of the biofertilization strategies. In this study, in vitro and greenhouse experiments were carried out to investigate P and K solubilization traits of nine Actinobacteria (P13, P14, P15, P16, P17, P18, BC3, BC10, and BC11) under fertilization with rock phosphate (RP). K and P solubilization were evaluated on Alexandrov and NBRIP media containing mica and six RP samples, respectively. The actinobacterial strains were able to solubilize K in Alexandrov medium supplemented with RP. However, when soluble P was used instead of RP, only four strains of Actinobacteria (Streptomyces alboviridis P18–Streptomyces griseorubens BC3–Streptomyces griseorubens BC10 and Nocardiopsis alba BC11) solubilized K. The solubilization values of K ranged from 2.6 to 41.45 mg/L while those of P varied from 0.1 to 32 mg/L. Moreover, all strains were able to produce IAA, siderophore, HCN, and ammonia and significantly improved the germination rate and the vigor index of wheat. The pot experiments revealed that four strains (Streptomyces alboviridis P18, Streptomyces griseorubens BC3, Streptomyces griseorubens BC10, and Nocardiopsis alba BC11) significantly improved the growth parameters of wheat, namely root length (1.75–23.84%), root volume (41.57–71.46%), root dry weight (46.89–162.41%), shoot length (8.92–23.56%), and shoot dry weight (2.56–65.68%) compared to the uninoculated control. These findings showed that Streptomyces griseorubens BC10 and Nocardiopsis alba BC11 are promising candidates for the implementation of efficient biofertilization strategies to improve soil fertility and plant yield under rock P and rock K fertilization.
L-Alanine Prototrophic Suppressors Emerge from L-Alanine Auxotroph through Stress-Induced Mutagenesis in Escherichia coli
Authors: Mishima Harutaka , Watanabe Hirokazu , Uchigasaki Kei , Shimoda So , Seki Shota , Kumagai Toshitaka , Nochi Tomonori , Ando Tasuke , Yoneyama Hiroshi
Published: February 2021

In Escherichia coli, L-alanine is synthesized by three isozymes: YfbQ, YfdZ, and AvtA. When an E. coli L-alanine auxotrophic isogenic mutant lacking the three isozymes was grown on L-alanine-deficient minimal agar medium, L-alanine prototrophic mutants emerged considerably more frequently than by spontaneous mutation; the emergence frequency increased over time, and, in an L-alanine-supplemented minimal medium, correlated inversely with L-alanine concentration, indicating that the mutants were derived through stress-induced mutagenesis. Whole-genome analysis of 40 independent L-alanine prototrophic mutants identified 16 and 18 clones harboring point mutation(s) in pyruvate dehydrogenase complex and phosphotransacetylase-acetate kinase pathway, which respectively produce acetyl coenzyme A and acetate from pyruvate. When two point mutations identified in L-alanine prototrophic mutants, in pta (D656A) and aceE (G147D), were individually introduced into the original L-alanine auxotroph, the isogenic mutants exhibited almost identical growth recovery as the respective cognate mutants. Each original- and isogenic-clone pair carrying the pta or aceE mutation showed extremely low phosphotransacetylase or pyruvate dehydrogenase activity, respectively. Lastly, extracellularly-added pyruvate, which dose-dependently supported L-alanine auxotroph growth, relieved the L-alanine starvation stress, preventing the emergence of L-alanine prototrophic mutants. Thus, L-alanine starvation-provoked stress-induced mutagenesis in the L-alanine auxotroph could lead to intracellular pyruvate increase, which eventually induces L-alanine prototrophy.
Gut and Reproductive Tract Microbiota Adaptation during Pregnancy: New Insights for Pregnancy-Related Complications and Therapy
Authors: De Siena Martina , Laterza Lucrezia , Matteo Maria Valeria , Mignini Irene , Schepis Tommaso , Rizzatti Gianenrico , Ianiro Gianluca , Rinninella Emanuele , Cintoni Marco , Gasbarrini Antonio
Published: February 2021

Pregnancy is characterized by maternal adaptations that are necessary to create a welcoming and hospitable environment for the fetus. Studies have highlighted how the microbiota modulates several networks in humans through complex molecular interactions and how dysbiosis (defined as quantitative and qualitative alterations of the microbiota communities) is related to human pathologies including gynecological diseases. This review analyzed how maternal uterine, vaginal, and gut microbiomes could impact on fetus health during the gestational period. We evaluated the role of a dysbiotic microbiota in preterm birth, chorioamnionitis, gestational diabetes mellitus and pre-eclampsia. For many years it has been hypothesized that newborns were sterile organisms but in the past few years this paradigm has been questioned through the demonstration of the presence of microbes in the placenta and meconium. In the future, we should go deeper into the concept of in utero colonization to better understand the role of microbiota through the phases of pregnancy. Numerous studies in the literature have already showed interesting results regarding the role of microbiota in pregnancy. This evidence gives us the hope that microbiota modulation could be a novel strategy to reduce the morbidity and mortality related to pregnancy complications in the future.
Assessment of Voltage Influence in Carbon Dioxide Fixation Process by a Photo-Bioelectrochemical System under Photoheterotrophy
Authors: Díaz-Rullo Edreira Sara , Barba Silvia , Vasiliadou Ioanna A. , Molina Raúl , Melero Juan Antonio , Espada Juan José , Puyol Daniel , Martínez Fernando
Published: February 2021

Bioelectrochemical systems are a promising technology capable of reducing CO2 emissions, a renewable carbon source, using electroactive microorganisms for this purpose. Purple Phototrophic Bacteria (PPB) use their versatile metabolism to uptake external electrons from an electrode to fix CO2. In this work, the effect of the voltage (from −0.2 to −0.8 V vs. Ag/AgCl) on the metabolic CO2 fixation of a mixed culture of PPB under photoheterotrophic conditions during the oxidation of a biodegradable carbon source is demonstrated. The minimum voltage to fix CO2 was between −0.2 and −0.4 V. The Calvin–Benson–Bassham (CBB) cycle is the main electron sink at these voltages. However, lower voltages caused the decrease in the current intensity, reaching a minimum at −0.8 V (−4.75 mA). There was also a significant relationship between the soluble carbon uptake in terms of chemical oxygen demand and the electron consumption for the experiments performed at −0.6 and −0.8 V. These results indicate that the CBB cycle is not the only electron sink and some photoheterotrophic metabolic pathways are also being affected under electrochemical conditions. This behavior has not been tested before in photoheterotrophic conditions and paves the way for the future development of photobioelectrochemical systems under heterotrophic conditions.
Aqueous Solubility of Organic Compounds for Flow Battery Applications: Symmetry and Counter Ion Design to Avoid Low-Solubility Polymorphs
Authors: Garcia Sergio Navarro , Yang Xian , Bereczki Laura , Kónya Dénes
Published: February 2021

Flow batteries can play an important role as energy storage media in future electricity grids. Organic compounds, based on abundant elements, are appealing alternatives as redox couples for redox flow batteries. The straightforward scalability, the independence of material sources, and the potentially attractive price motivate researchers to investigate this technological area. Four different benzyl-morpholino hydroquinone derivatives were synthesized as potential redox active species. Compounds bearing central symmetry were shown to be about an order of magnitude less soluble in water than isomers without central symmetry. Counter ions also affected solubility. Perchlorate, chlorate, sulfate and phosphate anions were investigated as counter ions. The formations of different polymorphs was observed, showing that their solubility is not a function of their structure. The kinetics of the transformation can give misleading solubility values according to Ostwald’s rule. The unpredictability of both the kinetics and the thermodynamics of the formation of polymorphs is a danger for new organic compounds designed for flow battery applications.
Designing Multiplayer Serious Games with Science Content
Authors: Garneli Varvara , Patiniotis Konstantinos , Chorianopoulos Konstantinos
Published: February 2021

Serious Games (SGs) could be enriched with collaborative learning techniques, an approach that has the potential to increase the players’ gaming and learning experience. However, the design of Multiplayer Serious Games (MSGs) with science content needs to be facilitated with methods and tools that provide coherent designs. This research proposes a methodology that employs the design technique of personas to effectively describe the multiplayer design patterns and the game narrative according to the content of a science school book and, at the same time, balancing the educational and the entertaining character of a SG. We evaluated the suggested methodology with two groups of professionals who were assigned with the task to design a MSG, integrating the same educational content according to the suggested methodology. The designs were qualitatively examined, confirming the potential of the Multiplayer Serious Game Methodology (MSGM) to facilitate the science content integration. We expect that the MSGM could assist groups of professionals, such as teachers and developers to create coherent MSG designs.
n-Octadecane/Fumed Silica Phase Change Composite as Building Envelope for High Energy Efficiency
Authors: Nguyen Giang Tien , Hwang Ha Soo , Lee Jiyoung , Cha Dong An , Park In
Published: February 2021

A novel n-octadecane/fumed silica phase change composite has been prepared as a building envelope with a high content of phase change material and improved energy efficiency. With a high porosity (88 vol%), the fumed silica provided sufficient space to impregnate a high quantity of n-octadecane (70 wt%). The composite exhibited high latent heat storage capacity (155.8 J/g), high crystallization fraction (96.5%), and a melting temperature of 26.76 °C close to that of pure n-octadecane. A 200 accelerated thermal cycle test confirmed good thermal reliability and chemical stability of the phase change composite. The thermal conductivity of n-octadecane was reduced by 34% after impregnation in fumed silica. A phase change composite panel was fabricated and compared to a commercial polystyrene foam panel. When used as the roof of a test room, the phase change composite panel more efficiently retarded heat transfer from a halogen lamp to the room and delayed the increase in the indoor temperature than that by the polystyrene panel. The indoor temperatures of the room with the phase change composite panel roof were 19.8 and 22.9 °C, while those with the polystyrene panel roof were 29.9 and 31.9 °C at 2200 and 9000 s after lamp illumination.
COVID-19 Crisis Creates Opportunity towards Global Monitoring & Surveillance
Authors: Donia Ahmed , Hassan Sammer-ul , Zhang Xunli , Al-Madboly Lamiaa , Bokhari Habib
Published: February 2021

The spectrum of emerging new diseases as well as re-emerging old diseases is broadening as infectious agents evolve, adapt, and spread at enormous speeds in response to changing ecosystems. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a recent phenomenon and may take a while to understand its transmission routes from less traveled territories, ranging from fomite exposure routes to wastewater transmission. The critical challenge is how to negotiate with such catastrophic pandemics in high-income countries (HICs ~20% of the global population) and low-and middle-income countries (LMICs ~ 80% of the global population) with a total global population size of approximately eight billion, where practical mass testing and tracing is only a remote possibility, particularly in low-and middle-income countries (LMICs). Keeping in mind the population distribution disparities of high-income countries (HICs) and LMICs and urbanisation trends over recent years, traditional wastewater-based surveillance such as that used to combat polio may help in addressing this challenge. The COVID-19 era differs from any previous pandemics or global health challenges in the sense that there is a great deal of curiosity within the global community to find out everything about this virus, ranging from diagnostics, potential vaccines/therapeutics, and possible routes of transmission. In this regard, the fact that the gut is the common niche for both poliovirus and SARS-CoV-2, and due to the shedding of the virus through faecal material into sewerage systems, the need for long-term wastewater surveillance and developing early warning systems for better preparedness at local and global levels is increasingly apparent. This paper aims to provide an insight into the ongoing COVID-19 crisis, how it can be managed, and what measures are required to deal with a current global international public health concern. Additionally, it shed light on the importance of using wastewater surveillance strategy as an early warning practical tool suitable for massive passive screening, as well as the urgent need for microfluidic technology as a rapid and cost-effective approach tracking SARS-CoV-2 in wastewater.
Molecular Pathotyping of Plasmodiophora brassicae—Genomes, Marker Genes, and Obstacles
Authors: Schwelm Arne , Ludwig-Müller Jutta
Published: February 2021

Here we review the usefulness of the currently available genomic information for the molecular identification of pathotypes. We focused on effector candidates and genes implied to be pathotype specific and tried to connect reported marker genes to Plasmodiophora brassicae genome information. The potentials for practical applications, current obstacles and future perspectives are discussed.
Diffraction Efficiency Characteristics for MEMS-Based Phase-Only Spatial Light Modulator with Nonlinear Phase Distribution
Authors: Ketchum Remington S. , Blanche Pierre-Alexandre
Published: February 2021

Micro-electro mechanical systems (MEMS)-based phase-only spatial light modulators (PLMs) have the potential to overcome the limited speed of liquid crystal on silicon (LCoS) spatial light modulators (SLMs) and operate at speeds faster than 10 kHz. This expands the practicality of PLMs to several applications, including communications, sensing, and high-speed displays. The complex structure and fabrication requirements for large, 2D MEMS arrays with vertical actuation have kept MEMS-based PLMs out of the market in favor of LCoS SLMs. Recently, Texas Instruments has adapted its existing DMD technology for fabricating MEMS-based PLMs. Here, we characterize the diffraction efficiency for one of these PLMs and examine the effect of a nonlinear distribution of addressable phase states across a range of wavelengths and illumination angles.