bluuebunny/crossref_metadata_2025 huggingface dataset:
Photobiomodulation with a 660-Nanometer Light-Emitting Diode Promotes Cell Proliferation in Astrocyte Culture
Authors: Yoon Sung-Ryeong , Hong Namgue , Lee Min-Young , Ahn Jin-Chul
Published: July 2021

Astrocytes act as neural stem cells (NSCs) that have the potential to self-renew and differentiate into other neuronal cells. The protein expression of these astrocytes depends on the stage of differentiation, showing sequential expression of multiple proteins such as octamer-binding transcription factor 4 (Oct4), nestin, glial fibrillary acidic protein (GFAP), and aldehyde dehydrogenase 1 family member L1 (aldh1L1). Photobiomodulation (PBM) affects cell apoptosis, proliferation, migration, and adhesion. We hypothesized that astrocyte proliferation and differentiation would be modulated by PBM. We used an optimized astrocyte culture method and a 660-nanometer light-emitting diode (LED) to enhance the biological actions of many kinds of cells. We determined that the 660-nanometer LED promoted the biological actions of cultured astrocytes by increasing the reactive oxygen species levels. The overall viability of the cultured cells, which included various cells other than astrocytes, did not change after LED exposure; however, astrocyte-specific proliferation was observed by the increased co-expression of GFAP and bromodeoxyuridine (BrdU)/Ki67. Furthermore, the 660-nanometer LED provides evidence of differentiation, as shown by the decreased Oct4 and GFAP co-expression and increased nestin and aldh1L1 expression. These results demonstrate that a 660-nanometer LED can modify astrocyte proliferation, which suggests the efficacy of the therapeutic application of LED in various pathological states of the central nervous system.
Integrin-Linked Kinase (ILK) Plays an Important Role in the Laminin-Dependent Development of Dorsal Root Ganglia during Chicken Embryogenesis
Authors: Mrówczyńska Ewa , Mazur Antonina Joanna
Published: July 2021

Integrin-linked kinase (ILK) is mainly localized in focal adhesions where it interacts and modulates the downstream signaling of integrins affecting cell migration, adhesion, and survival. The interaction of dorsal root ganglia (DRG) cells, being part of the peripheral nervous system (PNS), with the extracellular matrix (ECM) via integrins is crucial for proper PNS development. A few studies have focused on ILK’s role in PNS development, but none of these have focused on chicken. Therefore, we decided to investigate ILK’s role in the development of Gallus gallus domesticus’s DRG. First, using RT-PCR, Western blotting, and in situ hybridization, we show that ILK is expressed in DRG. Next, by immunocytochemistry, we show ILK’s localization both intracellularly and on the cell membrane of DRG neurons and Schwann cell precursors (SCPs). Finally, we describe ILK’s involvement in multiple aspects of DRG development by performing functional experiments in vitro. IgG-mediated interruption of ILK’s action improved DRG neurite outgrowth, modulated their directionality, stimulated SCPs migration, and impacted growth cone morphology in the presence of laminin-1 or laminin-1 mimicking peptide IKVAV. Taken together, our results show that ILK is important for chicken PNS development, probably via its exposure to the ECM.
The Immune Landscape of Osteosarcoma: Implications for Prognosis and Treatment Response
Authors: Cascini Caterina , Chiodoni Claudia
Published: July 2021

Osteosarcoma (OS) is a high-grade malignant stromal tumor composed of mesenchymal cells producing osteoid and immature bone, with a peak of incidence in the second decade of life. Hence, although relatively rare, the social impact of this neoplasm is particularly relevant. Differently from carcinomas, molecular genetics and the role of the tumor microenvironment in the development and progression of OS are mainly unknown. Indeed, while the tumor microenvironment has been widely studied in other solid tumor types and its contribution to tumor progression has been definitely established, tumor–stroma interaction in OS has been quite neglected for years. Only recently have new insights been gained, also thanks to the availability of new technologies and bioinformatics tools. A better understanding of the cross-talk between the bone microenvironment, including immune and stromal cells, and OS will be key not only for a deeper knowledge of osteosarcoma pathophysiology, but also for the development of novel therapeutic strategies. In this review, we summarize the current knowledge about the tumor microenvironment in OS, mainly focusing on immune cells, discussing their role and implication for disease prognosis and treatment response.
Clinically Malignant Breast Lesion in an Adolescent Girl: A Case Report
Authors: Sosnowska-Sienkiewicz Patrycja , Mańkowski Przemysław
Published: July 2021

Diseases of the breast in adolescent women are usually benign, and their treatment is simple using appropriate medical strategy and rarely surgical therapy. The whole team’s real challenge is when the girl presents malignant breast cancer symptoms such as a non-movable tumor, nipple discharge, nipple retraction, retraction of the skin, inflammatory infiltration of the breast, or ulceration. Presented here is a case of a 15-years-old girl with the features of a malignant neoplasm of the breast. There was an observed non-movable tumor, retraction of the nipple, inflammatory infiltration, and pain. The performed ultrasound and magnetic resonance imaging suggested a malignant lesion measuring 84 mm × 66 mm × 50 mm. After many diagnostic difficulties, the lesion evacuated spontaneously, and the abscess was diagnosed. In conclusion, not all features of a malignant breast tumor in adult women are typical for adolescent females. In young girls, breast diseases are usually benign, and appropriate diagnostics and therapy allow for an effective cure. Atypical breast lesions require the extraordinary cooperation of a multidisciplinary team.
Numerical Investigation for the Resin Filling Behavior during Ultraviolet Nanoimprint Lithography of Subwavelength Moth-Eye Nanostructure
Authors: Cui Yuanchi , Wang Xuewen , Zhang Chengpeng , Wang Jilai , Shi Zhenyu
Published: July 2021

Accurate analysis of the resin filling process into the mold cavity is necessary for the high-precision fabrication of moth-eye nanostructure using the ultraviolet nanoimprint lithography (UV-NIL) technique. In this research, a computational fluid dynamics (CFD) simulation model was proposed to reveal resin filling behavior, in which the effect of boundary slip was considered. By comparison with the experimental results, a good consistency was found, indicating that the simulation model could be used to analyze the resin filling behavior. Based on the proposed model, the effects of process parameters on resin filling behavior were analyzed, including resin viscosity, inlet velocity and resin thickness. It was found that the inlet velocity showed a more significant effect on filling height than the resin viscosity and thickness. Besides, the effects of boundary conditions on resin filling behavior were investigated, and it was found the boundary slip had a significant influence on resin filling behavior, and excellent filling results were obtained with a larger slip velocity on the mold side. This research could provide guidance for a more comprehensive understanding of the resin filling behavior during UV-NIL of subwavelength moth-eye nanostructure.
Structural and Electrochemical Properties of Scandia Alumina Stabilized Zirconia Thin Films
Authors: Sriubas Mantas , Virbukas Darius , Kainbayev Nursultan , Bockute Kristina , Laukaitis Giedrius
Published: July 2021

This work presents a systematic investigation of scandia alumina stabilized zirconia (ScAlSZ, composition: ZrO2:Sc2O3:Al2O3 93:6:1 wt.%) thin films (~2 μm). Thin films were formed by the e-beam evaporation method on 450 °C substrates. The influence of Al concentration on thin film microstructure, structure, and electrochemical properties was characterized by EDS, XRD, Raman, and EIS methods. It was found that the aluminum concentration in the deposited thin films decreased with an increase in the deposition rate. The concentration of Al changed from 15.9 to 3.8 at.% when the deposition rates were 0.2 and 1.6 nm/s, respectively. The crystallinity of the thin films depended strongly on the concentration of Al, resulting in an amorphous phase when Al concentration was 22.2 at.% and a crystalline phase when Al concentration was lower. ScAlSZ thin films containing 15.9 at.% of Al had monoclinic and tetragonal phases, while thin films with 1.6 and 3.8 at.% of Al had a mixture of cubic, tetragonal, and monoclinic phases. The phase transition was observed during the thermal annealing process. Cubic and rhombohedral phases formed in addition to monoclinic and tetragonal phases appeared after annealing ScAlSZ thin films containing 15.9 and 22.2 at.% of aluminum. The highest total ionic conductivity (σbulk = 2.89 Sm−1 at 800 °C) was achieved for ScAlSZ thin films containing 3.8 at.% of Al. However, thin films containing a higher concentration of aluminum had more than 10 times lower total conductivity and demonstrated changes in activation energy at high temperatures (>560 °C). Activation energies changed from ~1.10 to ~1.85 eV.
Challenges of Formation of Thin-Film Solid Electrolyte Layers on Non-Conductive Substrates by Electrophoretic Deposition
Authors: Kalinina Elena , Pikalova Elena , Ermakova Larisa , Bogdanovich Nina
Published: July 2021

In this work, the challenges associated with the formation of single and bilayer coatings based on Ce0.8Sm0.2O1.9 (SDC) and CuO modified BaCe0.5Zr0.3Y0.1Yb0.1O3−δ (BCZYYbO-CuO) solid state electrolytes on porous non-conducting NiO-SDC anode substrates by the method of electrophoretic deposition (EPD) are considered. Various approaches that had been selected after analysis of the literature data in order to carry out the EPD, are tested: direct deposition on a porous non-conductive anode substrate and multiple options for creating the conductivity of the anode substrate under EPD conditions such as the reduction of the NiO-SDC substrate and the creation of a surface conducting sublayer via synthesizing a polypyrrole (PPy) film. New effective method was proposed based on the deposition of a platinum layer on the front side of the substrate. It was ascertained that, during the direct EPD on the porous NiO-SDC substrate, the formation of a continuous coating did not occur, which may be due to insufficient porosity of the substrate used. It was shown that the use of reduced substrates leads to cracking and, in some cases, to the destruction of the entire SDC/NiO-SDC structure. The dependence of the electrolyte film sinterability on the substrate shrinkage was studied. In contrast to the literature data, the use of the substrates with a reduced pre-sintering temperature had no pronounced effect on the densification of the SDC electrolyte film. It was revealed that complete sintering of the SDC electrolyte layer with the formation of a developed grain structure is possible at a temperature of 1550 °C.
The Preparation, Morphological Characterization and Possible Electroanalytical Application of a Hydroxyapatite-Modified Glassy Carbon Electrode
Authors: Škugor Rončević Ivana , Buzuk Marijo , Buljac Maša , Vladislavić Nives
Published: July 2021

By simple modification of a GC electrode with biofunctional material, hydroxyapatite (HAp), an efficient electroanalytical tool, was designed and constructed. Modification of the GC surface includes two steps in synthesis: electrochemical deposition and chemical conversion. The properties, structure, and morphology of a nanosized material formed on a surface and absorbability were studied by electrochemical impedance spectroscopy, Fourier-transform infrared spectroscopy and scanning electron microscopy with energy-dispersive spectroscopy analysis. Numerous methods in this work confirmed that the developed method for controlled HAp deposition results in a HAp open structure and uniform morphology, which is capable of the selective absorption of the target species. The main goal of this study was the possibility of using a HAp-modified electrode for the fast screening of copper, cadmium, and lead content in honey and sugar samples. The electrochemical behavior and potential of the electroanalytical determination of heavy metals using the HAp/GC electrode were studied using cyclic voltammetry and square wave anodic stripping voltammetry. The HAp/GC electrode exhibited great performance in the determination of heavy metals, based on the reduction of target metals, because of the high absorbability of the HAp film and the electroanalytical properties of GC. A linear response between 10 and 1000 μg/L for Cu and Pb and 1 and 100 μg/L for Cd, with an estimated detection limit of 2.0, 10.0, and 0.9 μg/L, respectively, was obtained.
Tailoring Water Adsorption Capacity of APO-Tric
Authors: Mal Suzana , Ristić Alenka , Golobič Amalija , Zabukovec Logar Nataša
Published: July 2021

Microporous triclinic AlPO4-34, known as APO-Tric, serves as an excellent water adsorbent in thermal energy storage, especially for low temperature thermochemical energy storage. Increased water adsorption capacity of thermochemical material usually leads to higher thermal energy storage capacity, thus offering improved performance of the adsorbent. The main disadvantage of aluminophosphate-based TCM materials is their high cost due to the use of expensive organic templates acting as structure directing agents. Using ionic liquids as low cost solvents with associated structure directing role can increase the availability of these water adsorbents for TES applications. Here, a green synthesis of APO-Tric crystals at elevated and ambient pressure by using 1-ethyl-3-methyl imidazolium bromide ionic liquid is presented. Large 200 µm romboid shaped monocrystals were obtained at 200 °C after 6 days. The structure of APO-Tric and the presence of 1,3-dimetylimidazolium cation in the micropores were determined by single crystal XRD at room temperature and 150 K. Water sorption capacity of APO-Tric prepared by ionothermal synthesis at elevated pressure increased in comparison to the material obtained at hydrothermal synthesis most probably due to additional structural defects obtained after calcination. The reuse of exhausted ionic liquid was also confirmed, which adds to the reduction of toxicity and cost production of the aluminophosphate synthesis.
Hardening Parameter Homogenization for J2 Flow with Isotropic Hardening of Steel Fiber-Reinforced Concrete Composites
Authors: Sivtsev Petr V. , Smarzewski Piotr
Published: July 2021

Numerical modeling of the stress–strain state of composite materials such as fiber-reinforced concrete is a considerable computational challenge. Even if a computational grid with the resolution of all inclusions is built, it will take a great amount of time for the most powerful clusters to calculate the deformations of one concrete block with ideal parallelization. To solve this problem, the method of numerical homogenization is actively used. However, when plastic deformations are taken into account, the numerical homogenization becomes much more complicated due to nonlinearity. In this work, the description of the anisotropic nature of the hardening of the composite material and the numerical homogenization for the J2 flow with isotropic hardening is proposed. Here, the deformation of a composite material with a periodic arrangement of inclusions in the form of fibers is considered as a model problem. In this case, the assumption is made that inclusions have pure elastic properties. Numerical homogenization of the elasticity and plasticity parameters is performed on the representative element. The novelty of the work is related to the attempt at hardening parameter homogenization. The calculated effective parameters are used to solve the problem on a coarse mesh. The accuracy of using the computational algorithm is checked on model problems in comparison with the hardening parameters of the base material. The finite element implementation is built using the FEniCS computing platform and the fenics-solid library.
Digital Innovation in Oncological Primary Treatment for Well-Being of Patients: Psychological Caring as Prompt for Enhancing Quality of Life
Authors: Di Giacomo Dina , Guerra Federica , Cannita Katia , Di Profio Anna , Ranieri Jessica
Published: July 2021

One side-effect of oncological treatment is chemotherapy-induced alopecia (CIA), a temporary form of hair loss that could influence patients’ mental health. Digitised scalp cooling systems are assuming an important role in the clinical setting during adjuvant treatment, promising hair loss prevention and allowing an efficient procedure to reinforce patients’ mental health during chemotherapy by avoiding CIA. The present study was carried out through two research protocols: in Research Protocol 1, we conducted a randomised clinical study to evaluate the emotional impact of using scalp cooling technology in women with BC compared with a traditional chemotherapy setting; in Research Protocol 2, we conducted an observational pre-post study involving women with BC diagnosis being under adjuvant chemotherapy in two experimental conditions: no scalp cooling application and scalp cooling application. Seventy-four women undergoing chemotherapy, aged 30–55 years, were enrolled in both research protocols. We investigated oncological patients’ psychological dimensions including body image, body appreciation, expectations, and satisfaction with the scalp cooling treatment, with reference to chemotherapy treatment applying the scalp cooling solution. Our data evidenced the need to implement a supportive clinical approach via brief, tailored psychological intervention addressing patients’ progressive adaptation to chemotherapy adverse events and their concerns regarding induced alopecia and the value of the scalp cooling system. Patients receiving the innovative chemotherapy probably coped with it by neglecting its physical impact, instead focusing on avoiding alopecia by using the technological solution and neglecting the emotional impact of chemotherapy as a severe pharmacological treatment.
Population Structure and Seasonal Variability of two Luciferid Species (Decapoda: Sergestoidea) in the Western Gulf of Mexico
Authors: Sanvicente-Añorve Laura , Hernández-González Juan , Lemus-Santana Elia , Hermoso-Salazar Margarita , Violante-Huerta Marco
Published: July 2021

The population ecology of luciferids has been scarcely studied. This study examined the distribution and population parameters of Belzebub faxoni and Lucifer typus in the western Gulf of Mexico. Samples were collected using a Bongo net at 82 sampling stations during three periods (July, January, and October–November). Abundance data of species were subjected to a regression tree analysis to determine the main factors affecting their distribution. In addition, total length data of individuals were fitted to a logistic equation to estimate the size at first maturity. Food availability was the key factor affecting the distribution of B. faxoni, which exhibited its highest abundance over the inner shelf. In contrast, L. typus avoided low salinity waters (<35.9 psu), and its highest densities were found over the slope and oceanic areas. The sex ratio in B. faxoni was always biased towards females, but L. typus showed variable sex proportions. Several hypotheses attempting to explain these disparities are discussed. Size structure in B. faxoni favored small individuals in summer, the reproduction peak. In contrast, the L. typus population was always dominated by large individuals, probably transported by currents from the main hatching sites. Size at first maturity was higher in L. typus (females: 8.16 mm; males: 8.63 mm) than in B. faxoni (females: 6.53 mm; males: 6.74 mm). Information here provided may help to better understand the population dynamics of these species.
Orchids of Mongolia: Taxonomy, Species Richness and Conservation Status
Authors: Baasanmunkh Shukherdorj , Oyuntsetseg Batlai , Efimov Petr , Tsegmed Zagarjav , Vandandorj Sumiya , Oyundelger Khurelpurev , Urgamal Magsar , Undruul Altangerel , Khaliunaa Khurelbaatar , Namuulin Tugsuu , Choi Hyeok Jae
Published: July 2021

Orchidaceae is a diverse, globally important plant family with high conservation assessment and prioritization requirements. The checklist of Orchidaceae in Mongolia was updated based on herbarium materials, literature, and field observations. Mongolian orchids were revised as comprising 26 taxa belonging to 14 genera with major updates were conducted on Herminium and Epipactis. In particular, H. alaschanicum, previously noted in the Alashan Gobi region, was added to the flora of Mongolia based on literature and type specimens. Epipactis helleborine and E. palustris were excluded from the Mongolian flora owing to the absence of herbarium specimens and wild collection from Mongolia. Assessment of all orchid species at the national level resulted in 1, 4, 7, 11, and 2 species as critically endangered (CR), endangered (EN), vulnerable (VU), near threatened (NT), and data deficient (DD), respectively, according to IUCN criteria. Species richness and conservation gap analyses of 970 georeferenced orchid records based on 0.5° × 0.5° grid cells across 16 phytogeographical regions of Mongolia, showed that four phytogeographical regions, Khangai, Khuvgul, Khentii and Mongolian Dauria, have a high number of orchids. Regrettably, most orchid-rich locations in Mongolia are not fully within protected areas, highlighting the need for protection management updates. Based on herbarium collections, we prepared grid distribution maps of the 26 taxa using 40 × 40 km2 grids. Photographs of 18 taxa taken during fieldwork were included, providing valuable information on species morphology and typical habitat.
Absence of Both Right and Left Main Coronary in a COVID Survivor
Authors: Pop Marian , Pal Krisztina , Vaga Diana
Published: July 2021

The prevalence of isolated right coronary artery (RCA) absence ranges from 0.014% to 0.066% in the general population, but its combination with an absent left main (dual ostium left anterior descending [LAD] and super-dominant left circumflex [LCx]) has not been previously described. We report the case of a rare coronary artery anomaly: an absent RCA with LAD and LCx coronary arteries arising separately from the left coronary sinus. A 53-year-old male with recent COVID-19 infection was referred to our service for coronary computed tomography angiography (CCTA) due to the recent onset of atypical chest pain. The RCA was absent, with no vessel leaving the right or non-coronary sinus. The LAD and LCx emerged from the left coronary sinus, with a “double-barrel” appearance. The LAD was unremarkable, with small, non-stenosed calcified plaque. The LCx had a 3 mm diameter, arching downward in the left atrioventricular groove, passing through the crux cordis, continuing into the right atrioventricular groove, and ending as a left acute artery and sinonodal artery. No significant stenosis was found on any of the vessels, ruling out atherosclerotic coronary disease.
Existence of a Unique Solution to a Fractional Partial Differential Equation and Its Continuous Dependence on Parameters
Authors: Stegliński Robert
Published: July 2021

In the present paper we give conditions under which there exists a unique weak solution for a nonlocal equation driven by the integrodifferential operator of fractional Laplacian type. We argue for the optimality of some assumptions. Some Lyapunov-type inequalities are given. We also study the continuous dependence of the solution on parameters. In proofs we use monotonicity and variational methods.
Using Robots with Storytelling and Drama Activities in Science Education
Authors: Bravo Flor A. , Hurtado Jairo A. , González Enrique
Published: July 2021

Storytelling and drama are well-known teaching tools that can be used throughout the curriculum for the active participation of students in their own learning process. The introduction of robots in storytelling and drama activities provides students with a meaningful, multisensory, hands-on learning experience. This paper explores the potential and challenges of using storytelling and drama activities with robot actors in science teaching. We present the lessons learned from two experiences of storytelling and drama activities with robots in science education. Observations revealed that this approach facilitates the development of science concepts, creates a rich context to foster skills in students, creates a positive classroom environment, and improves the students’ attention and motivation. Finally, it was identified that there is a need to design low-cost expressive actor robots that are easily customizable. Additionally, the need to develop multi-robot programming interfaces that facilitate the creation of scripts for robots and their programming is also shown.
Prediction of Methanol Production in a Carbon Dioxide Hydrogenation Plant Using Neural Networks
Authors: Chuquin-Vasco Daniel , Parra Francis , Chuquin-Vasco Nelson , Chuquin-Vasco Juan , Lo-Iacono-Ferreira Vanesa
Published: July 2021

The objective of this research was to design a neural network (ANN) to predict the methanol flux at the outlet of a carbon dioxide dehydrogenation plant. For the development of the ANN, a database was generated, in the open-source simulation software “DWSIM”, from the validation of a process described in the literature. The sample consists of 133 data pairs with four inputs: reactor pressure and temperature, mass flow of carbon dioxide and hydrogen, and one output: flow of methanol. The ANN was designed using 12 neurons in the hidden layer and it was trained with the Levenberg–Marquardt algorithm. In the training, validation and testing phase, a global mean square (RMSE) value of 0.0085 and a global regression coefficient R of 0.9442 were obtained. The network was validated through an analysis of variance (ANOVA), where the p-value for all cases was greater than 0.05, which indicates that there are no significant differences between the observations and those predicted by the ANN. Therefore, the designed ANN can be used to predict the methanol flow at the exit of a dehydrogenation plant and later for the optimization of the system.
Gas Transition: Renewable Hydrogen’s Future in Eastern Australia’s Energy Networks
Authors: Gurieff Nicholas , Moghtaderi Behdad , Daiyan Rahman , Amal Rose
Published: July 2021

The energy transition for a net-zero future will require deep decarbonisation that hydrogen is uniquely positioned to facilitate. This technoeconomic study considers renewable hydrogen production, transmission and storage for energy networks using the National Electricity Market (NEM) region of Eastern Australia as a case study. Plausible growth projections are developed to meet domestic demands for gas out to 2040 based on industry commitments and scalable technology deployment. Analysis using the discounted cash flow technique is performed to determine possible levelised cost figures for key processes out to 2050. Variables include geographic limitations, growth rates and capacity factors to minimise abatement costs compared to business-as-usual natural gas forecasts. The study provides an optimistic outlook considering renewable power-to-X opportunities for blending, replacement and gas-to-power to show viable pathways for the gas transition to green hydrogen. Blending is achievable with modest (3%) green premiums this decade, and substitution for natural gas combustion in the long-term is likely to represent an abatement cost of AUD 18/tCO2-e including transmission and storage.
Separate Collected Versus Mechanical Segregated Organic Fractions in Terms of Fertilizers Suitability
Authors: Seruga Przemysław , Krzywonos Małgorzata
Published: July 2021

Nowadays, municipal solid waste (MSW) management is one of the most critical issues. MSW may threaten the environment; however, the concerning high organic fraction content can be useful. This study aimed to compare the suitability of mechanically sorted organic fraction (OF) of MSW and source-segregated biowaste for biofertilizer usage. The compost and the effluents compositions were analyzed. Compost derived from biowaste can be applied to the soil, while, after processing OFMSW, the metal contents are too high. The exceeding limit values were noted, e.g., lead (over 80 mg/kg) and chrome (75 mg/kg). Effluents from biowaste treatment fulfill the national and UE fertilizers’ requirements, considering the heavy metal contents, while effluents from OFMSW treatments exceed the limit values. The biggest exceedings were observed for nickel (over 3 mg/kg) and zinc (over 500 mg/kg). In general, the heavy metal contamination of byproducts from the OFMSW treatment was much higher. At the same time, the biogenic elements, e.g., nitrogen and phosphorus concentrations, were much lower than the biowaste treatment byproducts; however, even for them, the concentrations of the biogenic elements were too low to meet EU requirements. The compost and effluents derived from the biowaste treatment may be suitable for crop applications, considering the current national requirements.
On the Nature of the One-Diode Solar Cell Model Parameters
Authors: Sabadus Andreea , Paulescu Marius
Published: July 2021

The one-diode model is probably the most common equivalent electrical circuit of a real crystalline solar cell. Extensive research has focused on extracting model parameters from measurements performed in standard test conditions (STC), aiming to replicate the current-voltage characteristics (I-V). This study started from finding that, for the same solar cell, different scientific reports yield significantly different sets of parameters, all allowing for highly accurate replication of the measured I-V characteristics. This observation raises a big question: What is the true physical set of parameters? The present study attempts to address this question. For this purpose, a numerical experiment was conducted. The results show that there is an infinity of distinct sets of parameters that can replicate the I-V characteristics at STC via the one-diode model equation. The diode saturation current IS and the diode ideality factor compensate each other to preserve the open-circuit voltage VOC, always an input data point. Some possible approaches (e.g., the link between VOC and IS) that can lead to the physical set of parameters are discussed, highlighting their strengths and weaknesses. There is enough room for future research on finding a universal approach able to guarantee the accurate extraction of the one-diode model physical parameters.
Improved Monitoring and Diagnosis of Transformer Solid Insulation Using Pertinent Chemical Indicators
Authors: Behjat Vahid , Emadifar Reza , Pourhossein Mehrdad , Rao U. Mohan , Fofana Issouf , Najjar Reza
Published: July 2021

Transformers are generally considered to be the costliest assets in a power network. The lifetime of a transformer is mainly attributable to the condition of its solid insulation, which in turn is measured and described according to the degree of polymerization (DP) of the cellulose. Since the determination of the DP index is complex and time-consuming and requires the transformer to be taken out of service, utilities prefer indirect and non-invasive methods of determining the DP based on the byproduct of cellulose aging. This paper analyzes solid insulation degradation by measuring the furan concentration, recently introduced methanol, and dissolved gases like carbon oxides and hydrogen, in the insulating oil. A group of service-aged distribution transformers were selected for practical investigation based on oil samples and different kinds of tests. Based on the maintenance and planning strategy of the power utility and a weighted combination of measured chemical indicators, a neural network was also developed to categorize the state of the transformer in certain classes. The method proved to be able to improve the diagnostic capability of chemical indicators, thus providing power utilities with more reliable maintenance tools and avoiding catastrophic failure of transformers.
Numerical Modelling on CO2 Storage Capacity in Depleted Gas Reservoirs
Authors: Akai Takashi , Saito Naoki , Hiyama Michiharu , Okabe Hiroshi
Published: July 2021

Making an accurate estimate of the CO2 storage capacity before the commencement of a carbon capture and storage (CCS) project is crucial to the project design and feasibility investigation. We present herein a numerical modelling study on the CO2 storage capacity in depleted gas reservoirs. First, we show a simple volumetric equation that gives the CO2 storage capacity in a depleted gas reservoir, which considers the same volume of CH4 at reservoir pressure and temperature conditions produced from the reservoir. Next, the validity and the limitations of this equation are investigated using a numerical reservoir simulation with the various reservoir characteristics of reservoir heterogeneity, aquifer water encroachment, and rock compaction and its reversibility. Regardless of the reservoir heterogeneity, if a reservoir is subjected to a weak or moderate aquifer support, the volumetric equation provides an estimate of the CO2 storage capacity as structurally trapped gas within 1% of that estimated from numerical simulations. The most significant factor influencing the CO2 storage capacity is the reversibility of rock compaction, rather than the degree of rock compaction. If reservoir rocks have a strong hysteresis in their compaction and expansion behaviour, the material balance equation will overestimate the amount of structural CO2 trapping. All the simulation results show a fairly consistent amount of trapped CO2 as a dissolved component in water, which is 15∼17% of the structurally trapped CO2. Overall, our study presents the validity and the limitation of the simple material balance equation for estimating the CO2 storage capacity, which helps with designing a CCS project at the early stage.
Analysis of the Distributions of Displacement and Eddy Currents in the Ferrite Core of an Electromagnetic Transducer Using the 2D Approach of the Edge Element Method and the Harmonic Balance Method
Authors: Ludowicz Wojciech , Wojciechowski Rafał M.
Published: July 2021

The negative impact of the displacement currents on the operation of electromagnetic converters results in additional losses and faster insulation degradation, as well as the self-resonance phenomenon. Effective measurement of the dielectric displacement currents in converters is quite complex; thus, advanced simulation programs should be used. However, currently, they do not enable the analysis of the systems in terms of the displacement currents distribution. In order to elaborate an effective tool for analyzing the distribution of the displacement currents by means of the Finite Element Method, we have decided to supplement the well-known reluctance-conductance network model with an additional capacitance model. In the paper, equations for the linked reluctance-conductance-capacitance network model have been presented and discussed in detail. Moreover, we introduce in the algorithm the Harmonic Balance Finite Element Method (HBFEM) and the Fixed-Point Method. This approach enables us to create a field model of electromagnetic converters, which includes the electromagnetic core’s saturation effect. The application of these methods for the reluctance-conductance-capacitance model of the finite element has allowed us to develop a practical tool ensuring complex analysis of the magnetic flux, eddy, and the displacement currents’ distribution in electromagnetic converters with an axial symmetrical structure.
Corporate Social Responsibility of Water and Sanitation Company in the Czech Republic—Case Study
Authors: Pawlowska Elzbieta , Machnik-Slomka Joanna , Klosok-Bazan Iwona , Gono Miroslava , Gono Radomir
Published: July 2021

The issue discussed in this article concerns corporate social responsibility (CSR), which is playing an increasingly important role in the context of sustainable development of enterprises. The purpose of the current work was to assess the practices applied in the area of corporate social responsibility in water and sanitation companies, based on the opinions of employees and managers. The motivation for undertaking research on this topic resulted from the scarcity of scientific studies on the measurement of the corporate social responsibility concept in water and sanitization companies using a multidimensional approach based on the ISO 26000 standard. The study used methodological triangulation based on the use of qualitative and quantitative research methods to verify information from different sources. This approach allowed the authors to obtain the data more effectively and analyze the problem from numerous different perspectives. The study used an interview method that targeted water and sanitization utility staff. In-depth research was based on the case study method, which is particularly important when researching complex phenomena. For this purpose, surveys were carried out, the results of which indicate that corporate social responsibility of the surveyed enterprise is at a high level, and that there are statistically significant differences between individual dimensions of CSR. The results indicate that the surveyed company is oriented towards supporting activities in the area of corporate social responsibility, in accordance with the in the concept of sustainable development.
Energy Efficiency Assessment of Rail Freight Transport: Freight Tram in Berlin
Authors: Vajihi Mohammad , Ricci Stefano
Published: July 2021

Freight tram systems can potentially reduce commercial road vehicle use and, consequently, reduce congestion, accidents, air pollution, noise levels, and road maintenance costs. This paper explores the new application for the urban rail system as a sustainable solution for urban freight distribution. A significant problem in using rail for urban freight is determining the most efficient tram route, in terms of related costs and accessibility for the distribution centers and end-users. The study takes a systematic approach, based on identifying scenarios, existing tramlines, traveled distances, and time durations, and appraises the scheme through an energy consumption analysis to assess a hypothetical freight tram scheme. In a German case study in Berlin, a freight tram system delivered the goods of five delivery companies from their logistics hubs in the Pankow district to a micro depot instead of to the trucks. Three different path scenarios from logistics hubs to the micro depot were developed, to make comparisons based on energy consumption. Freight tram implementation in Berlin (compared to the current situation) resulted in a reduction of more than 7 tons of CO2 emissions per year, and 60 road-vehicle-kilometers per day, in exchange for 275 MJ of daily electric consumption.
The Long-Term Impact of Wind Power Generation on a Local Community: Economics Analysis of Subjective Well-Being Data in Chōshi City
Authors: Kunugi Yushi , Arimura Toshi H. , Nakai Miwa
Published: July 2021

In this study, we analyzed the external effects of wind turbines, which are often considered detrimental to the promotion of wind power generation. Understanding these externalities is essential to reaching a consensus with residents who live near the site of a planned wind turbine. Our research objective was to determine the relationship between wind turbines and people’s well-being in areas where they have been installed for a long time. We hypothesized that wind turbines would have a negative impact on people’s well-being. We conducted a survey by postal mail in Chōshi City, Chiba Prefecture, Japan, to examine the external effects of wind turbines, adopting a subjective well-being index to measure respondents’ well-being. Regression analysis suggests that having a view of wind power turbines has a positive effect on the subjective well-being of local residents. Moreover, the results indicate that such well-being increases with increasing distance from the turbines. Except for scenic elements, we found that wind turbines are not always considered desirable by residents. Therefore, it is important to further clarify the external influence of wind turbines and other facilities in local communities.
Dynamical Operation Based Robust Nonlinear Control of DC Microgrid Considering Renewable Energy Integration
Authors: Armghan Ammar , Azeem Muhammad Kashif , Armghan Hammad , Yang Ming , Alenezi Fayadh , Hassan Mudasser
Published: July 2021

The importance of microgrids has been acknowledged with the increasing amount of research in direct current (DC) microgrids. The main reason for this is the straightforward structure and efficient performance. In this research article, double integral sliding mode controllers (DISMCs) have been proposed for energy harvesting and DC microgrid management involving renewable sources and a hybrid energy storage system (HESS). DISMC offers a better dynamic response and reduced amount of chattering than the traditional sliding mode controllers. In the first stage, the state differential model for the grid was derived. Then, the nonlinear control laws were proposed for the PV system and hybrid energy storage system to achieve the main objective of voltage regulation at the DC link. In the later part, the system’s asymptotic stability was proven using Lyapunov stability criteria. Finally, an energy management algorithm was provided to ensure the DC microgrid’s smooth operation within the safe operating limit. The proposed system’s effectiveness was validated by implementing on MATLAB/Simulink software and comparing against sliding mode control and Lyapunov redesign. Moreover, to ensure the proposed controller’s practical viability for this scheme, it has been tested on real-time hardware-in-the-loop test bench.
NOx Emission from Diesel Vehicle with SCR System Failure Characterized Using Portable Emissions Measurement Systems
Authors: Su Sheng , Ge Yunshan , Zhang Yingzhi
Published: July 2021

Nitrogen oxides (NOx) emissions from diesel vehicles are major contributors to increasing fine particulate matter and ozone levels in China. The selective catalytic reduction (SCR) system can effectively reduce NOx emissions from diesel vehicles and is widely used in China IV and V heavy-duty diesel vehicles (HDDVs). In this study, two China IV HDDVs, one with SCR system failure and the other with a normal SCR system, were tested by using a portable emissions measurement system (PEMS). Results showed that the NOx emission factors of the test vehicle with SCR system failure were 8.42 g/kW∙h, 6.15 g/kW∙h, and 6.26 g/kW∙h at loads of 0%, 50%, and 75%, respectively, which were 2.14, 2.10, and 2.47 times higher than those of normal SCR vehicles. Emission factors, in terms of g/km and g/kW∙h, from two tested vehicles were higher on urban roads than those on suburban and motorways. The NOx emission factor of the vehicle with failed SCR system did not meet the China IV emission standard. The time-weighted results for normal SCR vehicle over the three road types show that, except for NOx emission factor 12.17% higher than the China IV limit at 0% load, the emission values are 16.21% and 27.54% below the China IV standard limit at 50% load and 75% load, respectively. In general, with higher load, NOx emissions (in terms of g/kW∙h) from the tested vehicle decreased. Furthermore, NO/NOx concentrations of both vehicles with normal and failed SCR systems showed a decreasing trend with the increase in load.
Grinding Behaviour of Microwave-Irradiated Mining Waste
Authors: Adewuyi Sefiu O. , Ahmed Hussin A. M.
Published: July 2021

The combined microwave-assisted sorting and microwave-assisted comminution of minerals has been proposed to reduce the huge grinding energy consumption in mineral processing. However, gangue minerals would be discarded after the sorting process despite the microwave energy absorbed during their treatment. Therefore, this paper investigates the effect of microwave pretreatment on the Bond work index (BWI) of quartz and calcite samples, as they represent the dominant gangues in many ores and are key inputs in the cement industry, which requires intensive grinding. The samples were characterized using a scanning electron microscope coupled with energy dispersive X-ray (SEM-EDX), and Fourier transform infrared (FTIR) and X-ray diffraction (XRD) methods. The BWIs of the two samples were determined before and after the microwave treatment (2.45 GHz, 1.7 kW) at 2, 4 and 6 minutes. SEM image analyses of the untreated and microwave-treated samples were performed using ImageJ software. The results showed that after 4 minutes of radiation treatment, the BWI of the studied quartz was reduced by 13.83%, while that of the calcite increased by 15.59%. The results of the SEM image analysis indicated that the quartz developed more cracks than the calcite under the same microwave treatment conditions. Based on these findings, microwave pretreatment is suitable to reduce the grinding energy of the studied quartz, but offers no energy-saving benefit to the studied calcite.
A Decade in Review after Idiopathic Scoliosis Was First Called a Complex Trait—A Tribute to the Late Dr. Yves Cotrel for His Support in Studies of Etiology of Scoliosis
Authors: Tang Nelson L. S. , Dobbs Matthew B. , Gurnett Christina A. , Qiu Yong , Lam T. P. , Cheng Jack C. Y. , Hadley-Miller Nancy
Published: July 2021

Adolescent Idiopathic Scoliosis (AIS) is a prevalent and important spine disorder in the pediatric age group. An increased family tendency was observed for a long time, but the underlying genetic mechanism was uncertain. In 1999, Dr. Yves Cotrel founded the Cotrel Foundation in the Institut de France, which supported collaboration of international researchers to work together to better understand the etiology of AIS. This new concept of AIS as a complex trait evolved in this setting among researchers who joined the annual Cotrel meetings. It is now over a decade since the first proposal of the complex trait genetic model for AIS. Here, we review in detail the vast information about the genetic and environmental factors in AIS pathogenesis gathered to date. More importantly, new insights into AIS etiology were brought to us through new research data under the perspective of a complex trait. Hopefully, future research directions may lead to better management of AIS, which has a tremendous impact on affected adolescents in terms of both physical growth and psychological development.