bluuebunny/crossref_metadata_2025 huggingface dataset:
Myeloperoxidase Inhibition Decreases the Expression of Collagen and Metallopeptidase in Mare Endometria under In Vitro Conditions
Authors: Amaral Ana , Fernandes Carina , Rebordão Maria Rosa , Szóstek-Mioduchowska Anna , Lukasik Karolina , Pinto-Bravo Pedro , Telo da Gama Luís , Jan Skarzynski Dariusz , Ferreira-Dias Graça
Published: January 2021

Neutrophils can originate neutrophil extracellular traps (NETs). Myeloperoxidase (MPO) is a peroxidase found in NETs associated to equine endometrosis and can be inhibited by 4-aminobenzoic acid hydrazide (ABAH). Metallopeptidases (MMPs) participate in extracellular matrix stability and fibrosis development. The objectives of this in vitro work were to investigate, in explants of mare’s endometrium, (i) the ABAH capacity to inhibit MPO-induced collagen type I (COL1) expression; and (ii) the action of MPO and ABAH on the expression and gelatinolytic activity of MMP-2/-9. Explants retrieved from the endometrium of mares in follicular or mid-luteal phases were treated with MPO, ABAH, or their combination, for 24 or 48 h. The qPCR analysis measured the transcription of COL1A2, MMP2, and MMP9. Western blot and zymography were performed to evaluate COL1 protein relative abundance and gelatinolytic activity of MMP-2/-9, respectively. Myeloperoxidase elevated COL1 relative protein abundance at both treatment times in follicular phase (p < 0.05). The capacity of ABAH to inhibit MPO-induced COL1 was detected in follicular phase at 48 h (p < 0.05). The gelatinolytic activity of activated MMP-2 augmented in mid-luteal phase at 24 h after MPO treatment, but it was reduced with MPO+ABAH treatment. The activity of MMP-9 active form augmented in MPO-treated explants. However, this effect was inhibited by ABAH in the follicular phase at 48 h (p < 0.05). By inhibiting the pro-fibrotic effects of MPO, it might be possible to reduce the development of endometrosis. Metallopeptidase-2 might be involved in an acute response to MPO in the mid-luteal phase, while MMP-9 might be implicated in a prolonged exposition to MPO in the follicular phase.
Heat Stress Reduces Metabolic Rate While Increasing Respiratory Exchange Ratio in Growing Pigs
Authors: Fausnacht Dane W. , Kroscher Kellie A. , McMillan Ryan P. , Martello Luciane S. , Baumgard Lance H. , Selsby Joshua T. , Hulver Matthew W. , Rhoads Robert P.
Published: January 2021

Heat stress (HS) diminishes animal production, reducing muscle growth and increasing adiposity, especially in swine. Excess heat creates a metabolic phenotype with limited lipid oxidation that relies on aerobic and anaerobic glycolysis as a predominant means of energy production, potentially reducing metabolic rate. To evaluate the effects of HS on substrate utilization and energy expenditure, crossbred barrows (15.2 ± 2.4 kg) were acclimatized for 5 days (22 °C), then treated with 5 days of TN (thermal neutral, 22 °C, n = 8) or HS (35 °C, n = 8). Pigs were fed ad libitum and monitored for respiratory rate (RR) and rectal temperature. Daily energy expenditure (DEE) and respiratory exchange ratio (RER, CO2:O2) were evaluated fasted in an enclosed chamber through indirect calorimetry. Muscle biopsies were obtained from the longissimus dorsi pre/post. HS increased temperature (39.2 ± 0.1 vs. 39.6 ± 0.1 °C, p < 0.01) and RER (0.91 ± 0.02 vs. 1.02 ± 0.02 VCO2:VO2, p < 0.01), but decreased DEE/BW (68.8 ± 1.7 vs. 49.7 ± 4.8 kcal/day/kg, p < 0.01) relative to TN. Weight gain (p = 0.80) and feed intake (p = 0.84) did not differ between HS and TN groups. HS decreased muscle metabolic flexibility (~33%, p = 0.01), but increased leucine oxidation (~35%, p = 0.02) compared to baseline values. These data demonstrate that HS disrupts substrate regulation and energy expenditure in growing pigs.
Assessment of Climate Change in Central Asia from 1980 to 2100 Using the Köppen-Geiger Climate Classification
Authors: He Huili , Luo Geping , Cai Peng , Hamdi Rafiq , Termonia Piet , De Maeyer Philippe , Kurban Alishir , Li Jianjun
Published: January 2021

The accelerated global warming and heterogeneous change in precipitation have been resulting in climate system shifts, which plays a key role in the stability of ecosystem and social economic development. Central Asia is account 80% of the temperate desert, characterized by fragile ecosystem; however, it has experienced the fastest warming in recent decades and projected warming in future. The Köppen-Geiger climate classification is a useful tool to assess the potential impacts of climate change on regional ecosystem. The spatial shift and temporal evolution of each climatic zone based on Köppen-Geiger climate classification are analyzed in historical and future period under different scenarios (RCP2.6, RCP4.5 and RCP8.5), high risk regions that might experience more frequent climatic zone shifts are delimited in this study, which could provide the useful information for developing mitigate strategies in coping with the warming threat. The hotter and dryer subtypes of arid climatic zone and warmer subtypes of temperate climatic zone expanded their coverage in Central Asia, corresponding to the tundra climatic, cooler subtype of arid and temperate climatic zone contracted. Based on a method defining the climate-sensitivity, high risk regions are mainly distributed in northern Kazakhstan and Tianshan Mountains region.
Epidemiology of Anthropometric Factors in Glioblastoma Multiforme—Literature Review
Authors: Simińska Donata , Korbecki Jan , Kojder Klaudyna , Kapczuk Patrycja , Fabiańska Marta , Gutowska Izabela , Machoy-Mokrzyńska Anna , Chlubek Dariusz , Baranowska-Bosiacka Irena
Published: January 2021

Although glioblastoma multiforme (GBM) is a widely researched cancer of the central nervous system, we still do not know its full pathophysiological mechanism and we still lack effective treatment methods as the current combination of surgery, radiotherapy, and chemotherapy does not bring about satisfactory results. The median survival time for GBM patients is only about 15 months. In this paper, we present the epidemiology of central nervous system (CNS) tumors and review the epidemiological data on GBM regarding gender, age, weight, height, and tumor location. The data indicate the possible influence of some anthropometric factors on the occurrence of GBM, especially in those who are male, elderly, overweight, and/or are taller. However, this review of single and small-size epidemiological studies should not be treated as definitive due to differences in the survey methods used. Detailed epidemiological registers could help identify the main at-risk groups which could then be used as homogenous study groups in research worldwide. Such research, with less distortion from various factors, could help identify the pathomechanisms that lead to the development of GBM.
The Development of Brain Network in Males with Autism Spectrum Disorders from Childhood to Adolescence: Evidence from fNIRS Study
Authors: Cao Wei , Zhu Huilin , Li Yan , Wang Yu , Bai Wuxia , Lao Uchong , Zhang Yingying , Ji Yan , He Sailing , Zou Xiaobing
Published: January 2021

In the current study, functional near-infrared spectroscopy (fNIRS) was used to collect resting-state signals from 77 males with autism spectrum disorders (ASD, age: 6~16.25) and 40 typically developing (TD) males (age: 6~16.58) in the theory-of-mind (ToM) network. The graph theory analysis was used to obtain the brain network properties in ToM network, and the multiple regression analysis demonstrated that males with ASD showed a comparable global network topology, and a similar age-related decrease in the medial prefrontal cortex area (mPFC) compared to TD individuals. Nevertheless, participants with ASD showed U-shaped trajectories of nodal metrics of right temporo-parietal junction (TPJ), and an age-related decrease in the left middle frontal gyrus (MFG), while trajectories of TD participants were opposite. The nodal metrics of the right TPJ was negatively associated with the social deficits of ASD, while the nodal metrics of the left MFG was negatively associated with the communication deficits of ASD. Current findings suggested a distinct developmental trajectory of the ToM network in males with ASD from childhood to adolescence.
Tumor Metabolome: Therapeutic Opportunities Targeting Cancer Metabolic Reprogramming
Authors: Márquez Javier , Matés José M.
Published: January 2021

The study of cancer metabolism is regaining center stage and becoming a hot topic in tumor biology and clinical research, after a period where such kind of experimental approaches were somehow forgotten or disregarded in favor of powerful functional genomic and proteomic studies [...]
Endoscopic Images by a Single-Shot Multibox Detector for the Identification of Early Cancerous Lesions in the Esophagus: A Pilot Study
Authors: Wang Yao-Kuang , Syu Hao-Yi , Chen Yi-Hsun , Chung Chen-Shuan , Tseng Yu Sheng , Ho Shinn-Ying , Huang Chien-Wei , Wu I-Chen , Wang Hsiang-Chen
Published: January 2021

Diagnosis of early esophageal neoplasia, including dysplasia and superficial cancer, is a great challenge for endoscopists. Recently, the application of artificial intelligence (AI) using deep learning in the endoscopic field has made significant advancements in diagnosing gastrointestinal cancers. In the present study, we constructed a single-shot multibox detector using a convolutional neural network for diagnosing different histological grades of esophageal neoplasms and evaluated the diagnostic accuracy of this computer-aided system. A total of 936 endoscopic images were used as training images, and these images included 498 white-light imaging (WLI) and 438 narrow-band imaging (NBI) images. The esophageal neoplasms were divided into three classifications: squamous low-grade dysplasia, squamous high-grade dysplasia, and squamous cell carcinoma, based on pathological diagnosis. This AI system analyzed 264 test images in 10 s, and the sensitivity, specificity, and diagnostic accuracy of this system in detecting esophageal neoplasms were 96.2%, 70.4%, and 90.9%, respectively. The accuracy of this AI system in differentiating the histological grade of esophageal neoplasms was 92%. Our system showed better accuracy in diagnosing NBI (95%) than WLI (89%) images. Our results showed the great potential of AI systems in identifying esophageal neoplasms as well as differentiating histological grades.
Trends in Research on Exosomes in Cancer Progression and Anticancer Therapy
Authors: Sinha Dona , Roy Sraddhya , Saha Priyanka , Chatterjee Nabanita , Bishayee Anupam
Published: January 2021

Exosomes, the endosome-derived bilayered extracellular nanovesicles with their contribution in many aspects of cancer biology, have become one of the prime foci of research. Exosomes derived from various cells carry cargoes similar to their originator cells and their mode of generation is different compared to other extracellular vesicles. This review has tried to cover all aspects of exosome biogenesis, including cargo, Rab-dependent and Rab-independent secretion of endosomes and exosomal internalization. The bioactive molecules of the tumor-derived exosomes, by virtue of their ubiquitous presence and small size, can migrate to distal parts and propagate oncogenic signaling and epigenetic regulation, modulate tumor microenvironment and facilitate immune escape, tumor progression and drug resistance responsible for cancer progression. Strategies improvised against tumor-derived exosomes include suppression of exosome uptake, modulation of exosomal cargo and removal of exosomes. Apart from the protumorigenic role, exosomal cargoes have been selectively manipulated for diagnosis, immune therapy, vaccine development, RNA therapy, stem cell therapy, drug delivery and reversal of chemoresistance against cancer. However, several challenges, including in-depth knowledge of exosome biogenesis and protein sorting, perfect and pure isolation of exosomes, large-scale production, better loading efficiency, and targeted delivery of exosomes, have to be confronted before the successful implementation of exosomes becomes possible for the diagnosis and therapy of cancer.
The Great Escape: The Power of Cancer Stem Cells to Evade Programmed Cell Death
Authors: Castelli Vanessa , Giordano Antonio , Benedetti Elisabetta , Giansanti Francesco , Quintiliani Massimiliano , Cimini Annamaria , d’Angelo Michele
Published: January 2021

Cancer is one of the primary causes of death worldwide. Tumour malignancy is related to tumor heterogeneity, which has been suggested to be due to a small subpopulation of tumor cells named cancer stem cells (CSCs). CSCs exert a key role in metastasis development, tumor recurrence, and also epithelial–mesenchymal transition, apoptotic resistance, self-renewal, tumorigenesis, differentiation, and drug resistance. Several current therapies fail to eradicate tumors due to the ability of CSCs to escape different programmed cell deaths. Thus, developing CSC-selective and programmed death-inducing therapeutic approaches appears to be of primary importance. In this review, we discuss the main programmed cell death occurring in cancer and the promising CSC-targeting agents developed in recent years. Even if the reported studies are encouraging, further investigations are necessary to establish a combination of agents able to eradicate CSCs or inhibit their growth and proliferation.
Correction: Shen, J.; et al. Biological Aging Marker p16INK4a in T Cells and Breast Cancer Risk. Cancers 2020, 12, 3122
Authors: Shen Jie , Song Renduo , Fuemmeler Bernard F. , McGuire Kandace P. , Chow Wong-Ho , Zhao Hua
Published: January 2021

The authors wish to make the following corrections to this paper [...]
The Impact of HIV- and ART-Induced Mitochondrial Dysfunction in Cellular Senescence and Aging
Authors: Schank Madison , Zhao Juan , Moorman Jonathan P. , Yao Zhi Q.
Published: January 2021

According to the WHO, 38 million individuals were living with human immunodeficiency virus (HIV), 25.4 million of which were using antiretroviral therapy (ART) at the end of 2019. Despite ART-mediated suppression of viral replication, ART is not a cure and is associated with viral persistence, residual inflammation, and metabolic disturbances. Indeed, due to the presence of viral reservoirs, lifelong ART therapy is required to control viremia and prevent disease progression into acquired immune deficiency syndrome (AIDS). Successful ART treatment allows people living with HIV (PLHIV) to achieve a similar life expectancy to uninfected individuals. However, recent studies have illustrated the presence of increased comorbidities, such as accelerated, premature immune aging, in ART-controlled PLHIV compared to uninfected individuals. Studies suggest that both HIV-infection and ART-treatment lead to mitochondrial dysfunction, ultimately resulting in cellular exhaustion, senescence, and apoptosis. Since mitochondria are essential cellular organelles for energy homeostasis and cellular metabolism, their compromise leads to decreased oxidative phosphorylation (OXPHOS), ATP synthesis, gluconeogenesis, and beta-oxidation, abnormal cell homeostasis, increased oxidative stress, depolarization of the mitochondrial membrane potential, and upregulation of mitochondrial DNA mutations and cellular apoptosis. The progressive mitochondrial damage induced by HIV-infection and ART-treatment likely contributes to accelerated aging, senescence, and cellular dysfunction in PLHIV. This review discusses the connections between mitochondrial compromise and cellular dysfunction associated with HIV- and ART-induced toxicities, providing new insights into how HIV and current ART directly impact mitochondrial functions and contribute to cellular senescence and aging in PLHIV. Identifying this nexus and potential mechanisms may be beneficial in developing improved therapeutics for treating PLHIV.
One-Step Methods to Fabricate Durable Superhydrophobic Coatings for Flexible Electronic Sensors
Authors: Liu Xiang , Chen Kai , Zhang Dekun , Guo Zhiguang
Published: January 2021

Inspired by lotus leaves in nature, superhydrophobic surfaces have attracted extensive attention in many fields. However, their complex preparation process, poor durability and high cost seriously restrict their large-scale application in industrial production. Based on the good flexibility and durability of carbon nanofibers, several simple modifier-free one-step approaches were adopted to fabricate a durable CNF/PVDF/PDMS conductive superhydrophobic coating. The fabricated coating not only possesses good superhydrophobicity to many kinds of liquids, but also has excellent self-cleaning and anti-fouling properties. In addition, the superhydrophobicity of the obtained multifunctional coating is stable even after harsh bending fatigue deformation, long immersion times and high-temperature treatment. Due to its strong adhesion and excellent conductivity, the CNF/PVDF/PDMS coating displays reliable mechanical stability and superior sensitivity. These distinct features make the obtained conductive superhydrophobic coating a good candidate for multifunctional smart sensors, with great application prospects in gesture detectors, waterproof wearable electronics and health monitors.
Comparative Study of Cold Sintering Process and Autoclave Thermo-Vapor Treatment on a ZnO Sample
Authors: Ivakin Yurii , Smirnov Andrey , Kholodkova Anastasia , Vasin Alexander , Kormilicin Mikhail , Kornyushin Maxim , Stolyarov Vladimir
Published: January 2021

Analysis of scanning electron microscopy images was used to study the changes in the crystal size distribution of ZnO, which occurred during its processing in an aqueous medium at 220–255 °C and an equilibrium vapor pressure in an autoclave. The results were compared with those of ZnO placed in a die for treatment under similar conditions supplemented with mechanical pressure application in the cold sintering process. In both cases, ZnO was treated in the presence of an activating additive: either zinc acetate or ammonium chloride. During autoclaving, a powder consisting of fine ZnO monocrystals was obtained, while the cold sintering process led to ceramics formation. Under vapor pressure and mechanical pressure, the aqueous medium affected ZnO transformation by the same mechanism of solid-phase mobility activation due to the additives’ influence. The higher the content of additives in the medium, and the higher the mechanical pressure, the more pronounced activating effect was observed. Mass transfer during the cold sintering process occurred mainly by the coalescence of crystals, while without mechanical pressure, the predominance of surface spreading was revealed. In the initial ZnO powder, the average crystal size was 0.193 μm. It grew up to 0.316–0.386 μm in a fine-crystalline powder formed in the autoclave and to an average grain size of 0.244–0.799 μm in the ceramics, which relative density reached 0.82–0.96. A scheme explaining the influence of an aqueous medium on the solid-phase mobility of ZnO structure was proposed. It was found that the addition of 7.6 mol% ammonium chloride to the reaction medium causes the processes of compaction and grain growth similar to those observed in ZnO Cold Sintering Process with the addition of 0.925 mol% zinc acetate.
Coupling between Blood Pressure and Subarachnoid Space Width Oscillations during Slow Breathing
Authors: Gruszecka Agnieszka , Nuckowska Magdalena K. , Waskow Monika , Kot Jacek , Winklewski Pawel J. , Guminski Wojciech , Frydrychowski Andrzej F. , Wtorek Jerzy , Bujnowski Adam , Lass Piotr , Stankovski Tomislav , Gruszecki Marcin
Published: January 2021

The precise mechanisms connecting the cardiovascular system and the cerebrospinal fluid (CSF) are not well understood in detail. This paper investigates the couplings between the cardiac and respiratory components, as extracted from blood pressure (BP) signals and oscillations of the subarachnoid space width (SAS), collected during slow ventilation and ventilation against inspiration resistance. The experiment was performed on a group of 20 healthy volunteers (12 females and 8 males; BMI =22.1±3.2 kg/m2; age 25.3±7.9 years). We analysed the recorded signals with a wavelet transform. For the first time, a method based on dynamical Bayesian inference was used to detect the effective phase connectivity and the underlying coupling functions between the SAS and BP signals. There are several new findings. Slow breathing with or without resistance increases the strength of the coupling between the respiratory and cardiac components of both measured signals. We also observed increases in the strength of the coupling between the respiratory component of the BP and the cardiac component of the SAS and vice versa. Slow breathing synchronises the SAS oscillations, between the brain hemispheres. It also diminishes the similarity of the coupling between all analysed pairs of oscillators, while inspiratory resistance partially reverses this phenomenon. BP–SAS and SAS–BP interactions may reflect changes in the overall biomechanical characteristics of the brain.
Beyond Causal Explanation: Einstein’s Principle Not Reichenbach’s
Authors: Silberstein Michael , Stuckey William Mark , McDevitt Timothy
Published: January 2021

Our account provides a local, realist and fully non-causal principle explanation for EPR correlations, contextuality, no-signalling, and the Tsirelson bound. Indeed, the account herein is fully consistent with the causal structure of Minkowski spacetime. We argue that retrocausal accounts of quantum mechanics are problematic precisely because they do not fully transcend the assumption that causal or constructive explanation must always be fundamental. Unlike retrocausal accounts, our principle explanation is a complete rejection of Reichenbach’s Principle. Furthermore, we will argue that the basis for our principle account of quantum mechanics is the physical principle sought by quantum information theorists for their reconstructions of quantum mechanics. Finally, we explain why our account is both fully realist and psi-epistemic.
Impacts of Road Infrastructure on the Environmental Efficiency of High Capacity Transportation in Harvesting of Renewable Wood Energy
Authors: Palander Teijo , Borz Stelian Alexandru , Kärhä Kalle
Published: January 2021

Transportation of renewable wood is increasing, being a necessary operation in logistics of the environmentally sustainable forest industry. However, increasing the transportation capacity is a source of greenhouse gas emissions. In addition to trucks’ emissions, maintaining road infrastructure affects the environment by the emissions of increasing utilization of HCT (high-capacity transportation), that is, larger and heavier vehicles, affecting the backhauling transportation and the efficiency of road-network combinations. Environmental efficiency is an important metric which is used for comparisons among technological alternatives employed in the utilization of energy derived from both fossil and renewable resources. Based on the enterprise resource planning (ERP) data (2018–2020), CO2 emissions of increasing HCT were calculated for a forest industry corporation. The reduction in average fuel consumption (ml t × km−1), between 52% and 70% in backhauling transportation, was 18.88%. In this respect, CO2 emissions were reduced by 4.52 g t × km−1, achieving 19.48 g t × km−1, based on the data from the 76 t vehicle combinations. Furthermore, the metric of total environmental efficiency shows the potential of the alternative road-network combinations for the HCT. The environmental efficiency of the 92 t HCT increased by 11% via an intensive road-network combination, compared to the most efficient 76 t HCT alternative and the efficiency increased by 21%, compared to the most efficient line-hauling alternative. Thus, the results are in favor of the backhauling transportation by the means of 92 t vehicles for HCT development. Furthermore, a sensitivity analysis demonstrates that technological improvement of the forest roads is essential for HCT in an increasing harvesting of renewable wood energy. Also, to achieve the maximum environmental efficiency of the HCT during upgrading of the forest roads, efficiency measurements of the HCT should be implemented in the transportation planning systems.
An N-type Naphthalene Diimide Ionene Polymer as Cathode Interlayer for Organic Solar Cells
Authors: Sorrentino Roberto , Penconi Marta , Andicsová-Eckstein Anita , Scavia Guido , Švajdlenková Helena , Kozma Erika , Luzzati Silvia
Published: January 2021

Polymer solar cells (PSCs) based on non-fullerene acceptors have the advantages of synthetic versatility, strong absorption ability, and high thermal stability. These characteristics result in impressive power conversion efficiency values, but to further push both the performance and the stability of PSCs, the insertion of appropriate interlayers in the device structure remains mandatory. Herein, a naphthalene diimide-based cathode interlayer (NDI-OH) is synthesized with a facile three-step reaction and used as a cathode interlayer for fullerene and non-fullerene PSCs. This cationic polyelectrolyte exhibited good solubility in alcohol solvents, transparency in the visible range, self-doping behavior, and good film forming ability. All these characteristics allowed the increase in the devices’ power conversion efficiencies (PCE) both for fullerene and non-fullerene-based PSCs. The successful results make NDI-OH a promising cathode interlayer to apply in PSCs.
Development of a Resolver-to-Digital Converter Based on Second-Order Difference Generalized Predictive Control
Authors: Estrabis Thyago , Gentil Gabriel , Cordero Raymundo
Published: January 2021

High-performance motor drives that operate in harsh conditions require an accurate and robust angular position measurement to correctly estimate the speed and reduce the torque ripple produced by angular estimation error. For that reason, a resolver is used in motor drives as a position sensor due to its robustness. A resolver-to-digital converter (RDC) is an observer used to get the angular position from the resolver signals. Most RDCs are based on angle tracking observers (ATOs). On the other hand, generalized predictive control (GPC) has become a powerful tool in developing controllers and observers for industrial applications. However, no GPC-based RDC with zero steady-state error during constant speed operation has been proposed. This paper proposes an RDC based on the second-order difference GPC (SOD-GPC). In SOD-GPC, the second-order difference operator is applied to design a GPC model with two embedded integrators. Thus, the SOD-GPC is used to design a type-II ATO whose steady-state angle estimation error tends to zero during constant speed operation. Simulation and experimental results prove that the proposed RDC system has better performance than other literature approaches.
Mitigating the Piston Effect in High-Speed Hyperloop Transportation: A Study on the Use of Aerofoils
Authors: Bose Aditya , Viswanathan Vimal K.
Published: January 2021

The Hyperloop is a concept for the high-speed ground transportation of passengers traveling in pods at transonic speeds in a partially evacuated tube. It consists of a low-pressure tube with capsules traveling at both low and high speeds throughout the length of the tube. When a high-speed system travels through a low-pressure tube with a constrained diameter such as in the case of the Hyperloop, it becomes an aerodynamically challenging problem. Airflow tends to get choked at the constrained areas around the pod, creating a high-pressure region at the front of the pod, a phenomenon referred to as the “piston effect.” Papers exploring potential solutions for the piston effect are scarce. In this study, using the Reynolds-Average Navier–Stokes (RANS) technique for three-dimensional computational analysis, the aerodynamic performance of a Hyperloop pod inside a vacuum tube is studied. Further, aerofoil-shaped fins are added to the aeroshell as a potential way to mitigate the piston effect. The results show that the addition of fins helps in reducing the drag and eddy currents while providing a positive lift to the pod. Further, these fins are found to be effective in reducing the pressure build-up at the front of the pod.
Enhanced Oil Removal by a Non-Toxic Biosurfactant Formulation
Authors: Mendes da Silva Santos Emília , Alvares da Silva Lira Isabela Regina , Moraes Meira Hugo , dos Santos Aguiar Jaciana , Diniz Rufino Raquel , Germano de Almeida Darne , Casazza Alessandro Alberto , Converti Attilio , Asfora Sarubbo Leonie , Moura de Luna Juliana
Published: January 2021

In this study, a new formulation of low-cost, biodegradable, and non-toxic biosurfactant by Candida sphaerica UCP 0995 was investigated. The study was conducted in a bioreactor on an industrial waste-based medium, and a central composite rotatable design was used for optimization. The best results, namely a 25.22 mN/m reduction in surface tension, a biosurfactant yield of 10.0 g/L, and a critical micelle concentration of 0.2 g/L, were achieved in 132 h at an agitation speed of 175 rpm and an aeration rate of 1.5 vvm. Compositional and spectroscopic analyses of the purified biosurfactant by chemical methods, Fourier transform infrared spectroscopy, and nuclear magnetic resonance suggested that it is a glycolipid-type biosurfactant, and it showed no cytotoxicity in the MTT assay. The biosurfactant, submitted to different formulation methods as a commercial additive, remained stable for 120 days at room temperature. Tensioactive properties and stability were evaluated at different pH values, temperatures, and salt concentrations. The biosurfactant obtained with all formulation methods demonstrated good stability, with tolerance to wide ranges of pH, temperature and salinity, enabling application under extreme environmental conditions. Bioremediation tests were performed to check the efficacy of the isolated biosurfactant and the selected microbial species in removing oil from soil. The results demonstrated that the biosurfactant produced has promising properties as an agent for the bioremediation of contaminated soil.
Optimal Voltage Control in MV Network with Distributed Generation
Authors: Kacejko Piotr , Pijarski Paweł
Published: January 2021

The article presents the concept of voltage control in a medium-voltage network, using the classical control of a HV/MV (High Voltage/Medium Voltage) transformer and active participation of distributed generation sources. The proposed solution is based on the results of the optimization process. The objective function is considered as a single-criterion—the voltage quality indicator or value of power losses in the network, and optionally as two-criteria (voltage quality and losses combined, with appropriately selected weight factors). The analysis carried out for random selection of independent variables, using the original heuristic algorithm, indicated a very high efficiency of the proposed control process, compared to the traditional approach. A significant improvement in the voltage quality index and reduction of losses was found, which justifies the advisability of looking for new solutions in the field of voltage control in MV networks, taking into account active participation of distributed generation.
Optimal Operation Scheduling Considering Cycle Aging of Battery Energy Storage Systems on Stochastic Unit Commitments in Microgrids
Authors: Lee Yong-Rae , Kim Hyung-Joon , Kim Mun-Kyeom
Published: January 2021

As renewable penetration increases in microgrids (MGs), the use of battery energy storage systems (BESSs) has become indispensable for optimal MG operation. Although BESSs are advantageous for economic and stable MG operation, their life degradation should be considered for maximizing cost savings. This paper proposes an optimal BESS scheduling for MGs to solve the stochastic unit commitment problem, considering the uncertainties in renewables and load. Through the proposed BESS scheduling, the life degradation of BESSs is minimized, and MG operation becomes economically feasible. To address the aforementioned uncertainties, a scenario-based method was applied using Monte Carlo simulation and the K-means clustering algorithm for scenario generation and reduction, respectively. By implementing the rainflow-counting algorithm, the BESS charge/discharge state profile was obtained. To formulate the cycle aging stress function and examine the life cycle cost (LCC) of a BESS more realistically, the nonlinear cycle aging stress function was partially linearized. Benders decomposition was adopted for minimizing the BESS cycle aging, total operating cost, and LCC. To this end, the general problem was divided into a master problem and subproblems to consider uncertainties and optimize the BESS charging/discharging scheduling problem via parallel processing. To demonstrate the effectiveness and benefits of the proposed BESS optimal scheduling in MG operation, different case studies were analyzed. The simulation results confirmed the superiority and improved performance of the proposed scheduling.
A Numerical Analysis of an Innovative Flow Ripple Reduction Method for External Gear Pumps
Authors: Marinaro Gianluca , Frosina Emma , Senatore Adolfo
Published: January 2021

In this paper, an innovative solution to minimize noise emission, acting on the flow ripple, in a prototype External Gear Pump (EGP) is presented. Firstly, a new tool capable to completely simulate this pump’s typologies, called EgeMATor, is presented; the hydraulic model, adopted for the simulation, is based on a lumped parameter method using a control volume approach. Starting from the pump drawing, thanks to different subroutines developed in different environments interconnected, it is possible to analyze an EGP. Results have been compared with the outputs of a three-dimensional CFD numerical model built up using a commercial code, already used with success by the authors. In the second section, an innovative solution to reduce the flow ripple is implemented. This technology is called Alternative Capacitive Volumes (ACV) and works by controlling and uniformizing the reverse flow, performing a consistent reduction of flow non-uniformity amplitude. In particular, a high reduction of the flow non-uniformity is notable in the frequency domain on the second fundamental frequency. The technology is easy to accommodate in a pump housing, especially for high-pressure components, and it helps with reducing the fluid-borne noise.
Operation of the Prototype Device for Induction Heating of Railway Turnouts at Various Operating Frequencies
Authors: Żelazny Robert , Jabłoński Paweł , Szczegielniak Tomasz
Published: January 2021

Devices for electric heating of railroad turnouts are elements of the railway infrastructure protecting railroad turnouts against blocking them by snow and ice in winter. They often operate based on the principle of resistance heating but other solutions are also emerging. In this paper, one of such new solutions using the phenomenon of electromagnetic induction was presented and tested under various conditions. In comparison with traditional resistive heaters, the inductive ones offer heat distribution directly to ice and snow without intermediation of rails. Moreover, they can use a wide range spectrum of frequency to shorten the melting time. The resistive and inductive devices were tested with respect to melting time, temperatures and energy consumption. It follows that the induction-based device offers much lower energy consumption at a level of 30%–60% of that by resistive heater. The details depend on frequency used, initial temperature and number of induction devices of action assumed equivalent to the resistive one. Inductive heating of turnouts also offers shorter times of operation, which are obtained for frequencies in the range 40–70 kHz. The inductive device was also tested with respect to magnetic field levels around it to assess its possible influence on nearby infrastructure.
Heat Transfer Enhancement inside Rectangular Channel by Means of Vortex Generated by Perforated Concave Rectangular Winglets
Authors: Syaiful  , Hendraswari Monica Pranita , S.U. M.S.K. Tony , Soetanto Maria F.
Published: January 2021

Passive methods using vortex generators (VGs) to enhance heat transfer have been a concern of researchers in recent decades. This study is intended to investigate the strength of the vortex generated by VGs by trying to reduce the pressure drop in the flow. The present work also takes into account the influence of the vortex intensity on the improvement of heat transfer, which can be indicated by the low value of the synergy angle. Experiments were carried out in the current investigation to validate the results of the numerical simulations in the Reynolds number range of 3102 to 16,132. The study results indicate that the observed heat transfer coefficients from the experimental and simulation results have a similar tendency with relatively small errors. A reduction in pressure drop is observed with the use of perforated concave rectangular winglets (PCRWs) against the nonperforated ones although there was a slight decrease in heat transfer improvements.
Real-Time Culture-Independent Microbial Profiling Onboard the International Space Station Using Nanopore Sequencing
Authors: Stahl-Rommel Sarah , Jain Miten , Nguyen Hang N. , Arnold Richard R. , Aunon-Chancellor Serena M. , Sharp Gretta Marie , Castro Christian L. , John Kristen K. , Juul Sissel , Turner Daniel J. , Stoddart David , Paten Benedict , Akeson Mark , Burton Aaron S. , Castro-Wallace Sarah L.
Published: January 2021

For the past two decades, microbial monitoring of the International Space Station (ISS) has relied on culture-dependent methods that require return to Earth for analysis. This has a number of limitations, with the most significant being bias towards the detection of culturable organisms and the inherent delay between sample collection and ground-based analysis. In recent years, portable and easy-to-use molecular-based tools, such as Oxford Nanopore Technologies’ MinION™ sequencer and miniPCR bio’s miniPCR™ thermal cycler, have been validated onboard the ISS. Here, we report on the development, validation, and implementation of a swab-to-sequencer method that provides a culture-independent solution to real-time microbial profiling onboard the ISS. Method development focused on analysis of swabs collected in a low-biomass environment with limited facility resources and stringent controls on allowed processes and reagents. ISS-optimized procedures included enzymatic DNA extraction from a swab tip, bead-based purifications, altered buffers, and the use of miniPCR and the MinION. Validation was conducted through extensive ground-based assessments comparing current standard culture-dependent and newly developed culture-independent methods. Similar microbial distributions were observed between the two methods; however, as expected, the culture-independent data revealed microbial profiles with greater diversity. Protocol optimization and verification was established during NASA Extreme Environment Mission Operations (NEEMO) analog missions 21 and 22, respectively. Unique microbial profiles obtained from analog testing validated the swab-to-sequencer method in an extreme environment. Finally, four independent swab-to-sequencer experiments were conducted onboard the ISS by two crewmembers. Microorganisms identified from ISS swabs were consistent with historical culture-based data, and primarily consisted of commonly observed human-associated microbes. This simplified method has been streamlined for high ease-of-use for a non-trained crew to complete in an extreme environment, thereby enabling environmental and human health diagnostics in real-time as future missions take us beyond low-Earth orbit.
“That’s What the Program Is All about… Building Relationships”: Exploring Experiences in an Urban Offering of the Indigenous Youth Mentorship Program in Canada
Authors: Ferguson Leah J. , Girolami Tammy , Thorstad Reed , Rodgers Carol D. , Humbert M. Louise
Published: January 2021

Peer mentorship is an effective approach for delivering health promotion programs that may be particularly useful among underrepresented populations. Advancing the peer-led approach, the Indigenous Youth Mentorship Program (IYMP) is a communal-led program rooted in Indigenous values aimed at the promotion of healthy lifestyles in children and youth. The program includes layers of multi-age mentoring (i.e., elementary students, high school student mentors, and young adult health leaders [YAHLs]) and incorporates three core components: physical activity, healthy eating, and cultural teachings. The purpose of this study was to qualitatively explore elementary student, mentor, and YAHL experiences in an urban IYMP offering. Eleven sharing circles were conducted; six with elementary students (n = 23; grade 4 and 5 students), two with mentors (n = 3; students enrolled in a grade 10 wellness girls class), and three with YAHLs (n = 6; undergraduate university students). Focus groups were also held with respective school teachers and principals. An inductive content analysis generated three themes that represent the perceived impacts of this urban IYMP offering: (1) Fostering Wellness, (2) Strengthening Meaningful Connections, and (3) Exploring Leadership. Findings are positioned within a communal mentorship framework that is circular and multi-directional. By bringing together Indigenous and non-Indigenous peoples, this program offering supports Indigenous cultural relevance in an urban-based wellness program.
Methodological Approach of the Iron and Muscular Damage: Female Metabolism and Menstrual Cycle during Exercise Project (IronFEMME Study)
Authors: Peinado Ana B. , Alfaro-Magallanes Victor M. , Romero-Parra Nuria , Barba-Moreno Laura , Rael Beatriz , Maestre-Cascales Cristina , Rojo-Tirado Miguel A. , Castro Eliane A. , Benito Pedro J. , Ortega-Santos Carmen P. , Santiago Elena , Butragueño Javier , García-de-Alcaraz Antonio , Rojo Jesús J. , Calderón Francisco J. , García-Bataller Alberto , Cupeiro Rocío
Published: January 2021

Background: The increase in exercise levels in the last few years among professional and recreational female athletes has led to an increased scientific interest about sports health and performance in the female athlete population. The purpose of the IronFEMME Study described in this protocol article is to determine the influence of different hormonal profiles on iron metabolism in response to endurance exercise, and the main markers of muscle damage in response to resistance exercise; both in eumenorrheic, oral contraceptive (OC) users and postmenopausal well-trained women. Methods: This project is an observational controlled randomized counterbalanced study. One hundered and four (104) active and healthy women were selected to participate in the IronFEMME Study, 57 of which were eumenorrheic, 31 OC users and 16 postmenopausal. The project consisted of two sections carried out at the same time: iron metabolism (study I) and muscle damage (study II). For the study I, the exercise protocol consisted of an interval running test (eight bouts of 3 min at 85% of the maximal aerobic speed), whereas the study II protocol was an eccentric-based resistance exercise protocol (10 sets of 10 repetitions of plate-loaded barbell parallel back squats at 60% of their one repetition maximum (1RM) with 2 min of recovery between sets). In both studies, eumenorrheic participants were evaluated at three specific moments of the menstrual cycle: early-follicular phase, late-follicular phase and mid-luteal phase; OC users performed the trial at two moments: withdrawal phase and active pill phase. Lastly, postmenopausal women were only tested once, since their hormonal status does not fluctuate. The three-step method was used to verify the menstrual cycle phase: calendar counting, blood test confirmation, and urine-based ovulation kits. Blood samples were obtained to measure sex hormones, iron metabolism parameters, and muscle damage related markers. Discussion: IronFEMME Study has been designed to increase the knowledge regarding the influence of sex hormones on some aspects of the exercise-related female physiology. Iron metabolism and exercise-induced muscle damage will be studied considering the different reproductive status present throughout well-trained females’ lifespan.
Environmental Substances Associated with Osteoporosis–A Scoping Review
Authors: Elonheimo Hanna , Lange Rosa , Tolonen Hanna , Kolossa-Gehring Marike
Published: January 2021

Introduction: Osteoporosis is a disease having adverse effects on bone health and causing fragility fractures. Osteoporosis affects approximately 200 million people worldwide, and nearly 9 million fractures occur annually. Evidence exists that, in addition to traditional risk factors, certain environmental substances may increase the risk of osteoporosis. Methods: The European Human Biomonitoring Initiative (HBM4EU) is a joint program coordinating and advancing human biomonitoring in Europe. HBM4EU investigates citizens’ exposure to several environmental substances and their plausible health effects aiming to contribute to policymaking. In HBM4EU, 18 priority substances or substance groups were selected. For each, a scoping document was prepared summarizing existing knowledge and health effects. This scoping review is based on these chemical-specific scoping documents and complementary literature review. Results: A possible link between osteoporosis and the body burden of heavy metals, such as cadmium (Cd) and lead (Pb), and industrial chemicals such as phthalates and per- and poly-fluoroalkyl substances (PFASs) was identified. Conclusions: Evidence shows that environmental substances may be related to osteoporosis as an adverse health effect. Nevertheless, more epidemiological research on the relationship between health effects and exposure to these chemicals is needed. Study results are incoherent, and pervasive epidemiological studies regarding the chemical exposure are lacking.
The Tridirectional Relationship among Physical Activity, Stress, and Academic Performance in University Students: A Systematic Review and Meta-Analysis
Authors: Wunsch Kathrin , Fiedler Janis , Bachert Philip , Woll Alexander
Published: January 2021

Higher education students often suffer from physiological and psychological health problems caused by stress, which may negatively impact their academic performance (AP). Physical activity (PA) can be a promising strategy to buffer these stress-induced complaints. Therefore, the aim of this investigation was to summarize evidence for the tridimensional construct of PA, stress, and AP, as well as to quantify the relationships among these variables. Five databases (PubMed, Scopus, SMEI, ERIC, and Web of Science) were systematically searched in November 2019 for publications that examined PA, stress, and AP of university students, without any restrictions regarding the publication period. The systematic review includes four original research studies with a moderate-to-high risk of bias. Results of included studies were narratively summarized and quantified in a meta-analysis using random effect models. Whereas study results point to a positive relation between PA and AP, relationships between PA and stress seem to be negative, while the relation between stress and AP is undecided. The meta-analysis found no significant associations and considerable heterogeneity of the results. Findings indicate a research gap concerning the connection of PA, stress, and AP in university students. Future studies should use validated measuring tools and consider the timepoint of data collection in order to extract truly stressful periods.