bluuebunny/crossref_metadata_2025 huggingface dataset:
Ground Stability Analysis in Non-Open-Cut Tunneling Method Using Small-Diameter Steel Pipe Piles
Authors: Kim Jonguk , Kim Jung-joo , Rehman Hafeezur , Yoo Hankyu
Published: October 2020

The non-open-cut method is used for constructing tunnels under existing roads without blocking traffic. Various non-open-cut methods use pipe roofs made of medium- and large-diameter steel pipe piles. However, the risk of ground settlement or heave is involved during the application of such piles. Therefore, research is conducted through model tests and numerical analysis on the non-open-cut method to investigate these problems using small-diameter piles. The progress of tunnel construction is divided into two repetitive steps. The first step (Stage 1) involves pulling back the pressure panel, and the second step involves propelling the precast structure (Stage 2). The behaviors of the pipe piles and ground displacement are analyzed according to the cover depth, tunnel size, existence and nonexistence of the shoe structure, and progress of tunnel construction. Small-diameter piles reduce the displacement during both stages. With a decrease in cover depth, the stress acting on the pile decreases during Stage 1 and increases during Stage 2. The presence of the shoe structure reduces the stress on the pile during both stages. The ground behavior based on the construction progress indicates that the ground settlement increases during Stage 1; however, no correlation is observed during Stage 2 at low depth.
In or Out of the Checklist? DNA Barcoding and Distribution Modelling Unveil a New Species of Crocidura Shrew for Italy
Authors: Mori Emiliano , Brambilla Mattia , Ramazzotti Fausto , Ancillotto Leonardo , Mazza Giuseppe , Russo Danilo , Amori Giovanni , Galimberti Andrea
Published: October 2020

The genus Crocidura (Eulipotyphla, Soricidae) is the most speciose genus amongst mammals, i.e., it includes the highest number of species. Different species are distinguished by skull morphology, which often prevents the identification of individuals in the field and limits research on these species’ ecology and biology. We combined species distribution models and molecular analyses to assess the distribution of cryptic Crocidura shrews in Italy, confirming the occurrence of the greater white-toothed shrew Crocidura russula in the northwest of the country. The molecular identification ascertained the species’ presence in two distinct Italian regions. Accordingly, species distribution modelling highlighted the occurrence of areas suitable for C. russula in the westernmost part of northern Italy. Our results confirm the role of Italy as a mammal hotspot in the Mediterranean; additionally, they also show the need to include C. russula in Italian faunal checklists. To conclude, we highlight the usefulness of combining different approaches to explore the presence of cryptic species outside their known ranges. Since the similar, smaller C. suaveolens may be displaced by the larger C. russula through competitive exclusion, the latter might be the species actually present where C. suaveolens had been reported previously. A comprehensive and detailed survey is therefore required to assess the current distribution of these species.
Demand Flexibility Enabled by Virtual Energy Storage to Improve Renewable Energy Penetration
Authors: Fambri Gabriele , Badami Marco , Tsagkrasoulis Dimosthenis , Katsiki Vasiliki , Giannakis Georgios , Papanikolaou Antonis
Published: October 2020

The increasing resort to renewable energy distributed generation, which is needed to mitigate anthropogenic CO2 emissions, leads to challenges concerning the proper operation of electric distribution systems. As a result of the intrinsic nature of Renewable Energy Sources (RESs), this generation shows a high volatility and a low predictability that make the balancing of energy production and consumption difficult. At the same time, the electrification of new energy-intensive sectors (such as heating) is expected. This complex scenario paves the way for new sources of flexibility that will have more and more relevance in the coming years. This paper analyses how the electrification of the heating system, combined with an electric flexibility utilisation module, can be used to mitigate the problems related to the fluctuating production of RES. By using Power-to-Heat (P2H) technologies, buildings are able to store the overproduction of RES in the form of thermal energy for end-use according to the principle of the so-called Virtual Energy Storage (VES). A context-aware demand flexibility extraction based on the VES model and the flexibility upscale and utilisation on district-level through grid simulation and energy flow optimisation is presented in the paper. The involved modules have been developed within the PLANET (PLAnning and operational tools for optimising energy flows and synergies between energy NETworks) H2020 European project and interact under a unified co-simulation framework with the PLANET Decision Support System (DSS) for the analysis of multi-energy scenarios. DSS has been used to simulate a realistic future energy scenario, according to which the imbalance problems triggered by RES overproduction are mitigated with the optimal exploitation of the demand flexibility enabled by VES.
Smoothed Particle Hydrodynamics Simulation of High Velocity Impact Dynamics of Molten Sand Particles
Authors: Chaussonnet Geoffroy , Bravo Luis , Flatau Alison , Koch Rainer , Bauer Hans-Jörg
Published: October 2020

Sand ingestion is highly detrimental for gas turbines because it leads to erosion and corrosion of engine components, accelerating material fatigue and contributing to global engine failure. In this paper the high velocity impact of a molten sand particle onto a solid wall is investigated by means of the Smoothed Particles Hydrodynamics method where the three phases are taken into account. Nominal conditions are a 25 μm particle composed of molten sand (dynamic viscosity μl=11 Pa·s) impacting the wall at a velocity of 250 m/s. The influence of different parameters are explored such as the mechanical properties of the molten sand particle (density, viscosity, surface tension), the impact conditions (velocity magnitude, particle size and angle of impact) as well as the particle shape (sphere or cube with different geometrical features impacting the wall). It is found that the particles do not form a lamella during the impact but mostly conserve its initial shape. It is also confirmed that sharp features such as edges lead to a larger normal pressure at the impact location. Correlations to quantify (i) the spread factor, (ii) the maximum and mean impact force and impact pressure and (iii) the slip distance are derived for the first time based on the investigated parameters. The importance of these correlations is that they provide information needed to implement low-order models for studying impact and deposition of molten sand in engineering simulations.
Mitigating Potential-Induced Degradation (PID) Using SiO2 ARC Layer
Authors: Dhimish Mahmoud , Hu Yihua , Schofield Nigel , G. Vieira Romênia
Published: October 2020

Potential-induced degradation (PID) of photovoltaic (PV) cells is one of the most severe types of degradation, where the output power losses in solar cells may even exceed 30%. In this article, we present the development of a suitable anti-reflection coating (ARC) structure of solar cells to mitigate the PID effect using a SiO2 ARC layer. Our PID testing experiments show that the proposed ARC layer can improve the durability and reliability of the solar cell, where the maximum drop in efficiency was equal to 0.69% after 96 h of PID testing using an applied voltage of 1000 V and temperature setting at 85 °C. In addition, we observed that the maximum losses in the current density are equal to 0.8 mA/cm2, compared with 4.5 mA/cm2 current density loss without using the SiO2 ARC layer.
Simulations of Aerodynamic Separated Flows Using the Lattice Boltzmann Solver XFlow
Authors: Chávez-Modena M. , Martínez J. L. , Cabello J. A. , Ferrer E.
Published: October 2020

We present simulations of turbulent detached flows using the commercial lattice Boltzmann solver XFlow (by Dassault Systemes). XFlow’s lattice Boltzmann formulation together with an efficient octree mesh generator reduce substantially the cost of generating complex meshes for industrial flows. In this work, we challenge these meshes and quantify the accuracy of the solver for detached turbulent flows. The good performance of XFlow when combined with a Large-Eddy Simulation turbulence model is demonstrated for different industrial benchmarks and validated using experimental data or fine numerical simulations. We select five test cases: the Backward-facing step the Goldschmied Body the HLPW-2 (2nd High-Lift Prediction Workshop) full aircraft geometry, a NACA0012 under dynamic stall conditions and a parametric study of leading edge tubercles to improve stall behavior on a 3D wing.
Condensation of an Azeotropic Mixture inside 2.5 mm ID Minitubes
Authors: Diani Andrea , Rossetto Luisa
Published: October 2020

The ongoing miniaturization of air conditioning and refrigeration systems, in order to limit, as much as possible, the refrigerant charge, calls for smaller and smaller heat exchangers. Besides, the new environmental regulations are calling for new pure refrigerants or refrigerants mixtures with lower values of global warming potentials (GWPs). In this context, this paper analyzes the possible implementation of minitubes during condensation of the azeotropic mixture R513A. Two minitubes are tested: a smooth tube with an inner diameter of 2.5 mm, and a microfin tube with an inner diameter at the fin tip of 2.4 mm. The effects of vapor quality (varied in the range 0.10–0.99), of mass velocity (varied in the range 200–1000 kg m−2 s−1), and of saturation temperature (30 °C and 40 °C) on the heat transfer coefficient are investigated. The experimental results indicate that the heat transfer coefficient increases as both vapor quality and mass velocity increase, both in the case of the smooth tube and of the microfin tube, but the slope of the heat transfer coefficient trend respect to vapor quality is higher in the case of the microfin tube. The microfin tube shows, on average, heat transfer coefficients are 79% higher than those of the smooth tube under the same working conditions. Since R513A is a possible substitute of R134a, some experimental data during condensation heat transfer are also compared against those for R134a. Finally, the experimental results are compared against values estimated by empirical correlations available in the open literature.
Drought, Wellbeing and Adaptive Capacity: Why Do Some People Stay Well?
Authors: Austin Emma K. , Handley Tonelle , Kiem Anthony S. , Rich Jane L. , Perkins David , Kelly Brian
Published: October 2020

Drought is a threat to public health. Individual and community adaptive capacity is crucial when responding to the impacts of drought. Gaps remain in the understandings of the relationship between wellbeing and adaptive capacity, and whether increased wellbeing can lead to improved adaptive capacity (or vice versa). This paper explores the relationship between drought, wellbeing and adaptive capacity to provide insights that will inform actions to enhance adaptive capacity, and hence increase opportunities for effective drought adaptation. The theory of salutogenesis and the associated sense of coherence (SOC) are used to measure adaptive capacity and to explain why some individuals remain well and adapt to adversity while others do not. An online survey of rural residents (n = 163) in drought-affected New South Wales (NSW), Australia, was conducted from November 2018 to January 2019. Linear regression was used to model the relationships between SOC, sociodemographic factors, drought and wellbeing. Findings demonstrate that SOC is strongly correlated with wellbeing. Drought condition did not influence adaptive capacity, although adaptive capacity and drought-related stress were only weakly correlated. Increased wellbeing was found to be associated with stronger adaptive capacity and therefore, an individuals’ capacity to cope with adversity, such as drought.
Curcumin Loaded Nanoliposomes Localization by Nanoscale Characterization
Authors: Arab-Tehrany Elmira , Elkhoury Kamil , Francius Gregory , Jierry Loic , Mano Joao F. , Kahn Cyril , Linder Michel
Published: October 2020

Curcumin is a hydrophobic drug gaining growing attention because of its high availability, its innocuity, and its anticancer, antitumoral, and antioxidative activity. However, its poor ‎‎bioavailability in the human body, caused by its low aqueous solubility and fast degradation, ‎‎presents a big hurdle for its oral administration. Here, we used nano-vesicles made of ‎‎phospholipids to carry and protect curcumin in its membrane. Various curcumin amounts were ‎‎encapsulated in the produced phospholipid system to form drug-loaded liposomes. ‎Curcumin’s ‎concentration was evaluated using UV-visible measurements. The maximal ‎amount of curcumin ‎that could be added to liposomes was assessed. Nuclear magnetic ‎resonance (NMR) analyses ‎were used to determine curcumin’s interactions and localization ‎within the phospholipid ‎membrane of the liposomes. X-ray scattering (SAXS) and atomic ‎force microscopy (AFM) ‎experiments were performed to characterize the membrane structure ‎and organization, as well as its ‎mechanical properties at the nanoscale. Conservation of the membrane’s properties is found with ‎the addition of curcumin in various ‎amounts before saturation, allowing the preparation of a ‎defined nanocarrier with desired ‎amounts of the drug.
The Application of Next-Generation Sequencing to Define Factors Related to Oral Cancer and Discover Novel Biomarkers
Authors: Kim Soyeon , Lee Joo Won , Park Young-Seok
Published: October 2020

Despite the introduction of next-generation sequencing in the realm of DNA sequencing technology, it is not often used in the investigation of oral squamous cell carcinoma (OSCC). Oral cancer is one of the most frequently occurring malignancies in some parts of the world and has a high mortality rate. Patients with this malignancy are likely to have a poor prognosis and may suffer from severe facial deformity or mastication problems even after successful treatment. Therefore, a thorough understanding of this malignancy is essential to prevent and treat it. This review sought to highlight the contributions of next-generation sequencing (NGS) in unveiling the genetic alterations and differential expressions of miRNAs involved in OSCC progression. By applying an appropriate eligibility criterion, we selected relevant studies for review. Frequently identified mutations in genes such as TP53, NOTCH1, and PIK3CA are discussed. The findings of existing miRNAs (e.g., miR-21) as well as novel discoveries pertaining to OSCC are also covered. Lastly, we briefly mention the latest findings in targeted gene therapy and the potential use of miRNAs as biomarkers. Our goal is to encourage researchers to further adopt NGS in their studies and give an overview of the latest findings of OSCC treatment.
Effect of the Particle Size of Al/Ni Multilayer Powder on the Exothermic Characterization
Authors: Miyake Shugo , Izumi Taisei , Yamamoto Rino
Published: October 2020

In this study, the exothermic temperature performance of various Al/Ni multilayer powders with particle sizes ranging from under 75 to over 850 µm, which generate enormous heat during self-propagating exothermic reactions, was determined using a high-speed sampling pyrometer. The Al/Ni multilayer powders were prepared by a cold-rolling and pulverizing method. The multilayer constitution of the Al/Ni multilayer powders was examined by observing the cross-section of the powders using scanning electron microscopy; the results indicate that the powders had similar lamellar structures regardless of the particle size. Exothermic reactions were carried out to measure the temperature changes during the experiment using a pyrometer. We found that the maximum temperature and the duration of the exothermic reaction increased with an increase in the particle size caused by the heat dissipation of the surface area of the Al/Ni multilayer powder. This indicates that the thermal characteristics of the exothermic reaction of the Al/Ni multilayer powder can be controlled by adjusting the particle size of the Al/Ni multilayer powder. Finally, we concluded that this controllability of the exothermic phenomenon can be applied as a local heating source in a wide range of fields.
Costimulatory Effect of Rough Calcium Phosphate Coating and Blood Mononuclear Cells on Adipose-Derived Mesenchymal Stem Cells In Vitro as a Model of In Vivo Tissue Repair
Authors: Khlusov Igor A. , Litvinova Larisa S. , Shupletsova Valeria V. , Khaziakhmatova Olga G. , Malashchenko Vladimir V. , Yurova Kristina A. , Shunkin Egor O. , Krivosheev Vasilii V. , Porokhova Ekaterina D. , Sizikova Anastasiia E. , Safiullina Linara A. , Legostaeva Elena V. , Komarova Ekaterina G. , Sharkeev Yurii P.
Published: October 2020

Calcium phosphate (CaP) materials do not always induce ectopic vascularization and bone formation; the reasons remain unclear, and there are active discussions of potential roles for post-implantation hematoma, circulating immune and stem cells, and pericytes, but studies on adipose-derived stem cells (AMSCs) in this context are lacking. The rough (average surface roughness Ra = 2–5 µm) scaffold-like CaP coating deposited on pure titanium plates by the microarc oxidation method was used to investigate its subcutaneous vascularization in CBA/CaLac mice and in vitro effect on cellular and molecular crosstalk between human blood mononuclear cells (hBMNCs) and AMSCs (hAMSCs). Postoperative hematoma development on the CaP surface lasting 1–3 weeks may play a key role in the microvessel elongation and invasion into the CaP relief at the end of the 3rd week of injury and BMNC migration required for enhanced wound healing in mice. Satisfactory osteogenic and chondrogenic differentiation but poor adipogenic differentiation of hAMSCs on the rough CaP surface were detected in vitro by differential cell staining. The fractions of CD73+ (62%), CD90+ (0.24%), and CD105+ (0.41%) BMNCs may be a source of autologous circulating stem/progenitor cells for the subcutis reparation, but allogenic hBMNC participation is mainly related to the effects of CD4+ T cells co-stimulated with CaP coating on the in vitro recruitment of hAMSCs, their secretion of angiogenic and osteomodulatory molecules, and the increase in osteogenic features within the period of in vivo vascularization. Cellular and molecular crosstalk between BMNCs and AMSCs is a model of effective subcutis repair. Rough CaP surface enhanced angio- and osteogenic signaling between cells. We believe that preconditioning and/or co-transplantation of hAMSCs with hBMNCs may broaden their potential in applications related to post-implantation tissue repair and bone bioengineering caused by microarc CaP coating.
Genomic Virulence Features of Two Novel Species Nocardia barduliensis sp. nov. and Nocardia gipuzkoensis sp. nov., Isolated from Patients with Chronic Pulmonary Diseases
Authors: Nouioui Imen , Cortés-Albayay Carlos , Neumann-Schaal Meina , Vicente Diego , Cilla Gustavo , Klenk Hans-Peter , Marimón Jose María , Ercibengoa Maria
Published: October 2020

Strains 335427T and 234509T, isolated from two 76-year-old patients with chronic pulmonary diseases, were the subject of polyphasic taxonomic studies and comparative genomic analyses for virulence factors. The 16 rRNA gene sequence similarity between strains 335427T and 234509T and their closest phylogenetic neighbors Nocardia asiatica NBRC 100129T and Nocardia abscessus NBRC 100374T were 99.5% and 100%, respectively. Digital DNA–DNA hybridization values between the aforementioned studied strains were well below the 70% threshold for assigning prokaryotic strains to a novel species. Strains 335427T and 234509T have genome sizes of 8.49 Mpb and 8.07 Mpb, respectively, with G + C content of 68.5%. Isolate 335427T has C16:0, C18:1 ω9c, C18:0 and C18:0 10 methyl as major fatty acids (>15%) and mycolic acids formed of 52–54 carbon atoms. However, only C18:1 ω9c was detected for isolate 234509T, which had mycolic acids with 44–56 carbon. Based on phenotypic and genetic data, strains 335427T (DSM 109819T = CECT 9924T) and 234509T (DSM 111366T = CECT 30129T) merit recognition as novel species, which are named Nocardia barduliensis sp. nov. and Nocardia gipuzkoensis sp. nov., respectively. All the strains studied had homologous VF-associated genes to those described in M. tuberculosis, including experimentally verified virulence genes in humans related to tuberculosis. The narGHIJ (nitrate reduction pathway) and gvpAFGOJLMK (gas vesicles) genetic maps of strains 335427T, 234509T, NBRC 100129T and NBRC 100374T showed the same syntenic block and raise the question of whether their functions are interlinked during the infection of the human host. However, further research is required to decipher the role of the gas vesicle in the pathogenicity mechanism of Nocardia spp.
GaPO4 Single Crystals: Growth Condition by Hydrothermal Refluxing Method
Authors: Balitsky Denis , Philippot Etienne , Balitsky Vladimir , Balitskaya Ludmila , Setkova Tatiana , Bublikova Tatiana , Papet Philippe
Published: October 2020

Bulk GaPO4 is an advanced piezoelectric material operating under high temperatures according to the α-β phase transition at 970 °C. This work presents the technological development of a hydrothermal refluxing method first applied for GaPO4 single crystal growth. Crystals of 10–20 g were grown in mixtures of aqueous solutions of low- and high-vapor-pressure acids (H3PO4/HCl) at 180–240 °C (10–20 bars). The principal feature of the refluxing method is a spatial separation of crystal growth and nutrient dissolution zones. This leads to a constant mass transportation of the dissolved nutrient, even for materials with retrograde solubility. Mass transport is carried out by dissolution of GaPO4 nutrient in a dropping flow of condensed low-vapor-pressure solvent. This method allows an exact saturation at temperature of equilibrium and avoids spontaneous crystallization as well loss of seeds. Grown crystals have a moderate OH− content and reasonable structural uniformity. Moreover, the hydrothermal refluxing method allows a fine defining of GaPO4 concentration in aqueous solutions of H3PO4, H2SO4, HCl and their mixtures at set T–P parameters (T < 250 °C, p = 10–30 bars). The proposed method is relatively simple to use, highly reproducible for crystal growth of GaPO4 and probably could applied to other compounds with retrograde solubility.
Extraction Kinetics of Phenolic Antioxidants from the Hydro Distillation Residues of Rosemary and Effect of Pretreatment and Extraction Parameters
Authors: Psarrou Irini , Oreopoulou Antigoni , Tsimogiannis Dimitrios , Oreopoulou Vassiliki
Published: October 2020

Rosemary residue, remaining after the distillation of essential oil, is currently unexploited, while it is a source of phenolic antioxidant components. This raw material was used for the extraction of phenolic compounds by aqueous ethanol or acetone in a continuously stirred reactor. The experimental results were fitted with a two-stage diffusion model. The highest extraction rates, total phenolic content (TPC) recovery, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging capacity were obtained by acetone 60% and ethanol 60%. Grinding of the raw material enhanced the extraction rate and increased TPC yield and antioxidant capacity as the particle size decreased. Pre-treatment by maceration in water (4 h) dissolved a high amount of TPC and shortened the extraction time, while the combination with the pulsed electric field process did not provide further improvement. The use of ultrasound increased the efficiency of the extraction.
Diradicalar Character and Ring Stability of Mesoionic Heterocyclic Oxazoles and Thiazoles by Ab Initio Mono and Multi-Reference Methods
Authors: da Silva Filho Antonio João , da Cruz Dantas Lucinêz , de Santana Otávio Luís
Published: October 2020

Mesoionics are neutral compounds that cannot be represented by a fully covalent or purely ionic structure. Among the possible mesomeric structures of these compounds are the diradical electronic configurations. Theoretical and experimental studies indicate that some mesoionic rings are unstable, which may be related to a significant diradical character, that until then is not quantified. In this work, we investigated the diradical character of four heterocycles: 1,3-oxazol-5-one, 1,3-oxazol-5-thione, 1,3-thiazole-5-one, and 1,3-thiazole-5-thione. The oxazoles are known to be significatively less stable than thiazoles. DFT and ab initio single (B3LYP, MP2, CCSD, and QCISD) and ab initio multi-reference (MR-CISD) methods with three basis sets (6-311+G(d), aug-cc-pVDZ, and aug-cc-pVTZ) were employed to assess the diradical character of the investigated systems, in gas phase and DMSO solvent, from three criteria: (i) HOMO-LUMO energy gap, (ii) determination of energy difference between singlet and triplet wave functions, and (iii) quantification of the most significant diradical character (y0, determined in the unrestricted formalism). All of the results showed that the diradical character of the investigated systems is very small. However, the calculated electronic structures made it possible to identify the possible origin of the oxazoles instability, which can help the design of mesoionic systems with the desired properties.
Influence of Ultrasonic Wind Sensor Position on Measurement Accuracy under Full-Scale Conditions
Authors: Lipecki Tomasz , Jamińska-Gadomska Paulina , Sumorek Andrzej
Published: October 2020

A system designed for making field measurements of wind action on engineering structures is described. The system is composed of sonic anemometers, differential pressure sensors, a barometer, and a thermohygrometer. The focus of this study is to determine the indications of sonic anemometers; to accomplish this goal, wind tunnel tests were performed. The tests did not involve checking the accuracy of the devices themselves, but determining their indications under field measurement conditions where certain unavoidable errors resulting from their installation can appear. The anemometer measurement uncertainty with respect to wind speed and angle was determined. The devices were rotated in a horizontal plane and inclined against and with the mean wind speed direction in a wind tunnel. Different tunnel wind speeds were tested. The results indicate stable device readings at different horizontal plane positions at different wind speeds and a low sensitivity to changes in inclination against the inflow.
Spanish Costaleros’ Physical Activity and Their Quality of Life
Authors: Ubago-Jiménez José Luis , Zurita-Ortega Félix , Puertas-Molero Pilar , González-Valero Gabriel
Published: October 2020

(1) Physical activity is one of the most influencing factors in people’ quality of life. Likewise, the costaleros of the Holy Week of Andalusia (Spain) carry out an important effort with high intensity during an extended time without any preparation. This study was the aim of knowing the intensity of the physical activity practiced by the costaleros in relation to their quality of life. (2) A transversal study was carried out with 1057 costaleros in Andalusia (Spain), where 930 were male and 127 female, between the ages of 18–61 years old (31.26 ± 7.60). For this purpose, descriptive, inferential, and correlative analyses were developed. Accelerometers (ActiGraph) were used during the procession to know the intensity of physical activity and the SF-36 test to know the self-perceived state of health and quality of life. (3) The intensity of physical activity practiced by costaleros is moderate, and it is related with their quality of life. In addition, positive associations are found between general health and physical activity. (4) Participants’ quality of life is associated with physical activity and freedom from injury. In addition, the measurement by accelerometry provides real data on the intensity of the effort made.
A Review of Inkjet Printed Graphene and Carbon Nanotubes Based Gas Sensors
Authors: Pandhi Twinkle , Chandnani Ashita , Subbaraman Harish , Estrada David
Published: October 2020

Graphene and carbon nanotube (CNT)-based gas/vapor sensors have gained much traction for numerous applications over the last decade due to their excellent sensing performance at ambient conditions. Inkjet printing various forms of graphene (reduced graphene oxide or modified graphene) and CNT (single-wall nanotubes (SWNTs) or multiwall nanotubes (MWNTs)) nanomaterials allows fabrication onto flexible substrates which enable gas sensing applications in flexible electronics. This review focuses on their recent developments and provides an overview of the state-of-the-art in inkjet printing of graphene and CNT based sensors targeting gases, such as NO2, Cl2, CO2, NH3, and organic vapors. Moreover, this review presents the current enhancements and challenges of printing CNT and graphene-based gas/vapor sensors, the role of defects, and advanced printing techniques using these nanomaterials, while highlighting challenges in reliability and reproducibility. The future potential and outlook of this rapidly growing research are analyzed as well.
Transform-Based Multiresolution Decomposition for Degradation Detection in Cellular Networks
Authors: Fortes Sergio , Muñoz Pablo , Serrano Inmaculada , Barco Raquel
Published: October 2020

Anomaly detection in the performance of the huge number of elements that are part of cellular networks (base stations, core entities, and user equipment) is one of the most time consuming and key activities for supporting failure management procedures and ensuring the required performance of the telecommunication services. This activity originally relied on direct human inspection of cellular metrics (counters, key performance indicators, etc.). Currently, degradation detection procedures have experienced an evolution towards the use of automatic mechanisms of statistical analysis and machine learning. However, pre-existent solutions typically rely on the manual definition of the values to be considered abnormal or on large sets of labeled data, highly reducing their performance in the presence of long-term trends in the metrics or previously unknown patterns of degradation. In this field, the present work proposes a novel application of transform-based analysis, using wavelet transform, for the detection and study of network degradations. The proposed system is tested using cell-level metrics obtained from a real-world LTE cellular network, showing its capabilities to detect and characterize anomalies of different patterns and in the presence of varied temporal trends. This is performed without the need for manually establishing normality thresholds and taking advantage of wavelet transform capabilities to separate the metrics in multiple time-frequency components. Our results show how direct statistical analysis of these components allows for a successful detection of anomalies beyond the capabilities of detection of previous methods.
Identification, Decomposition and Segmentation of Impulsive Vibration Signals with Deterministic Components—A Sieving Screen Case Study
Authors: Gąsior Karolina , Urbańska Hanna , Grzesiek Aleksandra , Zimroz Radosław , Wyłomańska Agnieszka
Published: October 2020

Condition monitoring is a well-established field of research; however, for industrial applications, one may find some challenges. They are mostly related to complex design, a specific process performed by the machine, time-varying load/speed conditions, and the presence of non-Gaussian noise. A procedure for vibration analysis from the sieving screen used in the raw material industry is proposed in the paper. It is more for pre-processing than the damage detection procedure. The idea presented here is related to identification and extraction of two main types of components: (i) deterministic (D)—related to the unbalanced shaft(s) and (ii) high amplitude, impulsive component randomly (R) appeared in the vibration due to pieces of ore falling down of moving along the deck. If we could identify these components, then we will be able to perform classical diagnostic procedures for local damage detection in rolling element bearing. As deterministic component may be AM/FM modulated and each impulse may appear with different amplitude and damping, there is a need for an automatic procedure. We propose a method for signal processing that covers two main steps: (a) related to R/D decomposition and including signal segmentation to neglect AM/FM modulations, iterative sine wave fitting using the least square method (for each segment), signal filtering technique by subtraction fitted sine from the raw signal, the definition of the criterion to stop iteration by residuals analysis, (b) impulse segmentation and description (beginning, end, max amplitude) that contains: detection of the number of impulses in a decomposed random part of the raw signal, detection of the max value of each impulse, statistical analysis (probability density function) of max value to find regime-switching), modeling of the envelope of each impulse for samples that protrude from the signal, extrapolation (forecasting) envelope shape for samples hidden in the signal. The procedure is explained using simulated and real data. Each step is very easy to implement and interpret thus the method may be used in practice in a commercial system.
Innovation in Engineering Education for Sustainable Development—Introduction to a Special Issue
Authors: Sánchez-Carracedo Fermín , López David
Published: October 2020

Sustainability plays a key role in engineering education. Engineering students must learn to think long-term and understand that, in order to achieve a better world, they must situate their future professional activities within the framework of sustainable solutions. To this end, future engineers must be aware of the complexities of the social environment in which they are developing their work, and of the need to harmonize short-term improvements with sustainable development based on the long term. Education for Sustainable Development (ESD) in engineering is essential for the training of agents of change and transformation that can promote policies, strategies, and methods that enable a more sustainable future to be built. This Special Issue gathers six original research papers in the field of ESD in engineering, ranging from general issues such as formulating key issues required for any course in EDS, to the experience of introducing sustainability into very specific subjects. Therefore, this Special Issue is of particular value for both academic researchers and lecturers interested in introducing sustainability into their own teaching subjects.
Payment for Environment Services to Promote Compliance with Brazil’s Forest Code: The Case of “Produtores de Água e Floresta”
Authors: Oliveira Fiorini Ana Carolina , Swisher Marilyn , Putz Francis E.
Published: October 2020

Payments for ecosystems services (PES) can promote natural resource conservation by increasing compliance with environmental laws. Law enforcement and PES proponents assume that individuals make decisions about compliance based on expectations of gains, likelihood of being caught in non-compliance, and magnitude of sanctions. Brazil’s Forest Code, characterized by low levels of compliance, includes incentive and disincentive mechanisms. We interviewed landowners in the Atlantic Forest to understand their motivations to participate (or not) in a PES project, the effects of knowledge and perceptions of environmental regulations on compliance, and how both environmental regulations and PES affect land management decision-making. We found that neither expectations of financial gains nor PES payments drive behavioral change and that the perception of systemic corruption reduced compliance with environment regulations. There were important behavioral differences between long-term residents for whom the land is their main source of income and recent residents with little dependence on land-generated income.
Analysis of the Influence of Training and Feedback Based on Event Data Recorder Information to Improve Safety, Operational and Economic Performance of Road Freight Transport in Brazil
Authors: Pereira de Oliveira Luid , Jiménez Alonso Felipe , Vieira da Silva Marcelino Aurélio , Tostes de Gomes Garcia Breno , Messias Lopes Diana Mery
Published: October 2020

Road transport is the principal means of transporting freight and passengers in most developing countries, but several factors, both alone and in conjunction, contribute to increased inefficiency, risk and instability in the sector. The main factors are related to the high number of accidents, structural precariousness, fleet obsolescence, low-skilled drivers and high rates of greenhouse gas emissions. This paper evaluates the influence of implementing a training and feedback procedure associated with event data recorder (EDR) systems for the promotion of better behavior among professional drivers based on safety, operation and economy criteria. The analyses are based on interventions that were carried out during four monitoring phases using data generated by vehicles collected over 13 months of research. The data were converted into indicators and evaluated individually against the criteria and through data envelopment analysis (DEA). The analyses led to the conclusions that the use of EDR systems had positive impacts on all three of the criteria under analysis, and that safety levels can be increased without having to reduce productivity or increase fuel consumption. However, the safety criterion was more sensitive to the association between the technology and training process applied, leading to significant reductions in the indicators analyzed. The study contributes to the association between the methods of analysis and the adoption of specific indicators derived from time variables, leading to the conclusion that the use of EDR systems associated with management training and monitoring procedures can improve economic and operational results in road freight transport (RFT). Furthermore, using the trip data as a structural basis for the training and feedback proved to be very promising for the reduction of unsafe behavior to avoid road accidents.
Service Quality in Hospitality and the Sustainability Effect: Systematic Literature Review and Future Research Agenda
Authors: Oliveras-Villanueva Marc , Llach Josep , Perramon Jordi
Published: October 2020

This article presents a systematic review of the literature on quality of service and sustainable practices in the hospitality sector with the objective of analyzing the state of the art, identifying gaps for future lines of research, and defining a future research agenda. The number of articles on these topics, although not particularly high, does demonstrate a growing trend. Despite this growth, however, several untreated lines of research were detected in three specific areas. In the first area, emphasis is placed on the critical factors that affect the quality of service. In the second area are the specific practices and tools of sustainability and quality of service that affect development and business success. Finally, the third section analyses the impact of strategies and the management of sustainable practices and quality of service with respect to business development. Research questions have been defined for each area.
Analyses of Waste Treatment in Rural Areas of East Java with the Possibility of Low-Pressure Briquetting Press Application
Authors: Fajfrlíková Pavla , Brunerová Anna , Roubík Hynek
Published: October 2020

The study deals with the possibility of waste utilization by using briquetting technology (production of solid fuels) and the potential of the manual low-pressure briquetting press in rural and peri-urban areas of East Java, where firewood is still commonly used as a source of energy for heating and cooking (besides LPG). The research compares households from the Donowarih village (Malang regency) and from the Maron peri-urban area (Blitar regency). Through quantitative and qualitative research, we document the potential of briquette production from household waste and agriculture production. The population from the peri-urban area is interested and willing to invest more in the technology, even though a higher biomass production has been found in the rural area. Financial possibilities were similar in both areas (p = 0.8986). A positive correlation (R = 0.5146) was found between the level of education and level of potential investments. Thus, higher education level meant higher interest in technology and the willingness to invest in it. In both areas there is a potential for briquette production and demand for its usage. Nevertheless, further research is recommended to find the suitable composition of bio-briquettes after the installation of wooden manual low-pressure briquetting press.
The Land Sparing, Water Surface Use Efficiency, and Water Surface Transformation of Floating Photovoltaic Solar Energy Installations
Authors: Cagle Alexander E. , Armstrong Alona , Exley Giles , Grodsky Steven M. , Macknick Jordan , Sherwin John , Hernandez Rebecca R.
Published: October 2020

Floating photovoltaic solar energy installations (FPVs) represent a new type of water surface use, potentially sparing land needed for agriculture and conservation. However, standardized metrics for the land sparing and resource use efficiencies of FPVs are absent. These metrics are critical to understanding the environmental and ecological impacts that FPVs may potentially exhibit. Here, we compared techno-hydrological and spatial attributes of four FPVs spanning different climatic regimes. Next, we defined and quantified the land sparing and water surface use efficiency (WSUE) of each FPV. Lastly, we coined and calculated the water surface transformation (WST) using generation data at the world’s first FPV (Far Niente Winery, California). The four FPVs spare 59,555 m2 of land and have a mean land sparing ratio of 2.7:1 m2 compared to ground-mounted PVs. Mean direct and total capacity-based WSUE is 94.5 ± 20.1 SD Wm−2 and 35.2 ± 27.4 SD Wm−2, respectively. Direct and total generation-based WST at Far Niente is 9.3 and 13.4 m2 MWh−1 yr−1, respectively; 2.3 times less area than ground-mounted utility-scale PVs. Our results reveal diverse techno-hydrological and spatial attributes of FPVs, the capacity of FPVs to spare land, and the utility of WSUE and WST metrics.
Cross-Disciplinary Analysis of Cooperative Learning Dimensions Based on Higher Education Students’ Perceptions
Authors: Cañabate Dolors , Garcia-Romeu Maria Luisa , Menció Anna , Nogué Lluís , Planas Marta , Solé-Pla Joan
Published: October 2020

This study analyzes the perception, mainly on motivation, interpersonal relationships, and learning outcomes, of higher education students from seven university disciplines derived from Cooperative Learning (CL) activities undertaken in the course of their degree studies. The cross-disciplinary dimensional analysis on cooperative learning included students’ motivation, academic performance, students’ relationships within cooperative groups, group organization, and teacher involvement. The study was carried out using a questionnaire validated by a number of CL experts. The subsequent analysis of a sample of 162 student’s perceptions on the CL dimensions provided first, positive students’ perceptions regarding satisfaction, motivation, learning outcomes, and interpersonal relationships, and second, that differences between university degrees on CL were significant, suggesting a strong dependence of cooperative dimensions on the implemented approach.
Toxic Potential of Traditionally Consumed Mushroom Species—A Controversial Continuum with Many Unanswered Questions
Authors: Nieminen Petteri , Mustonen Anne-Mari
Published: October 2020

Mushroom poisonings remain a significant cause of emergency medicine. While there are well-known species, such as Amanita phalloides, causing life-threatening poisonings, there is also accumulating evidence of poisonings related to species that have been considered edible and are traditionally consumed. In particular, the Tricholoma equestre group was reported to cause myotoxicity. In addition, particular wild mushrooms that are traditionally consumed especially in Asia and Eastern Europe have been subject to suspicion due to possible mutagenicity. Hitherto, the causative agents of these effects often remain to be determined, and toxicity studies have yielded contradictory results. Due to this, there is no consensus about the safety of these species. The issue is further complicated by difficulties in species identification and other possible sources of toxicity, such as microbiological contamination during storage, leading to sometimes opposite conclusions about the edibility of a species. This review focuses on existing data about these types of mushroom poisonings, including the still sparse knowledge about the causative chemical agents. In addition, the aim is to initiate a meta-discussion about the issue and to give some suggestions about how to approach the situation from the viewpoint of the collector, the researcher, and the practicing physician.
High Titer Persistent Neutralizing Antibodies Induced by TSST-1 Variant Vaccine Against Toxic Shock Cytokine Storm
Authors: Roetzer Andreas , Stich Norbert , Model Nina , Schwameis Michael , Firbas Christa , Jilma Bernd , Eibl Martha M.
Published: October 2020

Staphylococcal superantigen toxins lead to a devastating cytokine storm resulting in shock and multi-organ failure. We have previously assessed the safety and immunogenicity of a recombinant toxic shock syndrome toxin 1 variant vaccine (rTSST-1v) in clinical trials (NCT02971670 and NCT02340338). The current study assessed neutralizing antibody titers after repeated vaccination with escalating doses of rTSST-1v. At study entry, 23 out of 34 subjects (67.6%) had neutralizing antibody titers inhibiting T cell activation as determined by 3H-thymidine incorporation at a serum dilution of ≤1:100 with similar figures for inhibition of IL-2 activation (19 of 34 subjects, 55.9%) as assessed by quantitative PCR. After the first vaccination, numbers of subjects with neutralization titers inhibiting T cell activation (61.7% ≥ 1:1000) and inhibiting IL-2 gene induction (88.2% ≥ 1:1000) increased. The immune response was augmented after the second vaccination (inhibiting T cell activation: 78.8% ≥ 1:1000; inhibiting IL-2 induction: 93.9% ≥ 1:1000) corroborated with a third immunization months later in a small subgroup of subjects. Assessment of IFNγ, TNFα and IL-6 inhibition revealed similar results, whereas neutralization titers did not change in placebo participants. Antibody titer studies show that vaccination with rTSST-1v in subjects with no/low neutralizing antibodies can rapidly induce high titer neutralizing antibodies persisting over months.
The Potentials of Computer Analyzing the Acoustic Characteristics of a Human Speech under Spaceflight Conditions.
Authors: Lebedeva S.A. , Shved D.M. , Gushin V.I.
Published: October 2020

The paper presents current approaches to the assessment of the psycho-physiological status of a human operator by analyzing his/her speaking and gives a historical review of an application of speech acoustic analysis in the field of military aviation and manned spaceflight as well as under conditions of on-ground model experiments. Various methods of mathematical analysis of a speech signal when determining the human emotional and functional status and techniques of noise suppression in audio recordings are also considered. The applicability of the said methods for non-invasive psycho-physiological monitoring of cosmonauts under spaceflight conditions was assessed.