bluuebunny/crossref_metadata_2025 huggingface dataset:
The Molecular Landscape of Hürthle Cell Thyroid Cancer Is Associated with Altered Mitochondrial Function—A Comprehensive Review
Authors: Kumari Sonam , Adewale Ruth , Klubo-Gwiezdzinska Joanna
Published: June 2020

Hürthle cell thyroid carcinoma (HTC) accounts for 3–5% of all thyroid malignancies. Widely invasive HTC is characterized by poor prognosis and limited responsiveness to standard therapy with radioiodine. The molecular landscape of HTC is significantly different from the genetic signature seen in other forms of thyroid cancer. We performed a comprehensive literature review on the association between the molecular features of HTC and cancer metabolism. We searched the Pubmed, Embase, and Medline databases for clinical and translational studies published between 1980 and 2020 in English, coupling “HTC” with the following keywords: “genomic analysis”, “mutations”, “exome sequencing”, “molecular”, “mitochondria”, “metabolism”, “oxidative phosphorylation”, “glycolysis”, “oxidative stress”, “reactive oxygen species”, and “oncogenes”. HTC is characterized by frequent complex I mitochondrial DNA mutations as early clonal events. This genetic signature is associated with the abundance of malfunctioning mitochondria in cancer cells. HTC relies predominantly on aerobic glycolysis as a source of energy production, as oxidative phosphorylation-related genes are downregulated. The enhanced glucose utilization by HTC is used for diagnostic purposes in the clinical setting for the detection of metastases by fluorodeoxyglucose positron emission tomography (FGD-PET/CT) imaging. A comprehensive metabolomic profiling of HTC in association with its molecular landscape might be necessary for the implementation of tumor-specific therapeutic approaches.
Competing Endogenous RNAs, Non-Coding RNAs and Diseases: An Intertwined Story
Authors: Ala Ugo
Published: June 2020

MicroRNAs (miRNAs), a class of small non-coding RNA molecules, are responsible for RNA silencing and post-transcriptional regulation of gene expression. They can mediate a fine-tuned crosstalk among coding and non-coding RNA molecules sharing miRNA response elements (MREs). In a suitable environment, both coding and non-coding RNA molecules can be targeted by the same miRNAs and can indirectly regulate each other by competing for them. These RNAs, otherwise known as competing endogenous RNAs (ceRNAs), lead to an additional post-transcriptional regulatory layer, where non-coding RNAs can find new significance. The miRNA-mediated interplay among different types of RNA molecules has been observed in many different contexts. The analyses of ceRNA networks in cancer and other pathologies, as well as in other physiological conditions, provide new opportunities for interpreting omics data for the field of personalized medicine. The development of novel computational tools, providing putative predictions of ceRNA interactions, is a rapidly growing field of interest. In this review, I discuss and present the current knowledge of the ceRNA mechanism and its implications in a broad spectrum of different pathologies, such as cardiovascular or autoimmune diseases, cancers and neurodegenerative disorders.
Checkpoint Inhibitors and Engineered Cells: New Weapons for Natural Killer Cell Arsenal Against Hematological Malignancies
Authors: Giuliani Massimo , Poggi Alessandro
Published: June 2020

Natural killer (NK) cells represent one of the first lines of defense against malignant cells. NK cell activation and recognition are regulated by a balance between activating and inhibitory receptors, whose specific ligands can be upregulated on tumor cells surface and tumor microenvironment (TME). Hematological malignancies set up an extensive network of suppressive factors with the purpose to induce NK cell dysfunction and impaired immune-surveillance ability. Over the years, several strategies have been developed to enhance NK cells-mediated anti-tumor killing, while other approaches have arisen to restore the NK cell recognition impaired by tumor cells and other cellular components of the TME. In this review, we summarize and discuss the strategies applied in hematological malignancies to block the immune check-points and trigger NK cells anti-tumor effects through engineered chimeric antigen receptors.
Mechanistic Models of Signaling Pathways Reveal the Drug Action Mechanisms behind Gender-Specific Gene Expression for Cancer Treatments
Authors: Çubuk Cankut , Can Fatma E. , Peña-Chilet María , Dopazo Joaquín
Published: June 2020

Despite the existence of differences in gene expression across numerous genes between males and females having been known for a long time, these have been mostly ignored in many studies, including drug development and its therapeutic use. In fact, the consequences of such differences over the disease mechanisms or the drug action mechanisms are completely unknown. Here we applied mechanistic mathematical models of signaling activity to reveal the ultimate functional consequences that gender-specific gene expression activities have over cell functionality and fate. Moreover, we also used the mechanistic modeling framework to simulate the drug interventions and unravel how drug action mechanisms are affected by gender-specific differential gene expression. Interestingly, some cancers have many biological processes significantly affected by these gender-specific differences (e.g., bladder or head and neck carcinomas), while others (e.g., glioblastoma or rectum cancer) are almost insensitive to them. We found that many of these gender-specific differences affect cancer-specific pathways or in physiological signaling pathways, also involved in cancer origin and development. Finally, mechanistic models have the potential to be used for finding alternative therapeutic interventions on the pathways targeted by the drug, which lead to similar results compensating the downstream consequences of gender-specific differences in gene expression.
Heparin Anticoagulant for Human Bone Marrow Does Not Influence In Vitro Performance of Human Mesenchymal Stromal Cells
Authors: Roger Yvonne , Burmeister Laura , Hamm Anika , Elger Kirsten , Dittrich-Breiholz Oliver , Flörkemeier Thilo , Hoffmann Andrea
Published: June 2020

Mesenchymal stromal cells (MSCs) are a promising cell source for tissue engineering and regenerative medicine. In our lab, we found that MSC preparations from bone marrow of many different donors had a limited capacity of in vitro differentiation into osteogenic and chondrogenic lineages—a capacity claimed to be inherent to MSCs. The current study was designed to test the hypothesis that the amount of heparin used as anticoagulant during bone marrow harvest had an inhibitory influence on the in vitro differentiation capacity of isolated MSCs. Bone marrow was obtained from the femoral cavity of twelve donors during total hip arthroplasty in the absence or presence of heparin. No coagulation was observed in the absence of heparin. The number of mononuclear cells was independent of heparin addition. Isolated MSCs were characterized by morphology, population doubling times, expression of cell surface antigens and in vitro differentiation. Results of these analyses were independent of the amount of heparin. Transcriptome analyses of cells from three randomly chosen donors and quantitative realtime PCR (qRT-PCR) analysis from cells of all donors demonstrated no clear effect of heparin on the transcriptome of the cells. This excludes heparin as a potential source of disparate results.
Expression of Annexin A2 Promotes Cancer Progression in Estrogen Receptor Negative Breast Cancers
Authors: Mahdi Amira F. , Malacrida Beatrice , Nolan Joanne , McCumiskey Mary E. , Merrigan Anne B. , Lal Ashish , Tormey Shona , Lowery Aoife J. , McGourty Kieran , Kiely Patrick A.
Published: June 2020

When breast cancer progresses to a metastatic stage, survival rates decline rapidly and it is considered incurable. Thus, deciphering the critical mechanisms of metastasis is of vital importance to develop new treatment options. We hypothesize that studying the proteins that are newly synthesized during the metastatic processes of migration and invasion will greatly enhance our understanding of breast cancer progression. We conducted a mass spectrometry screen following bioorthogonal noncanonical amino acid tagging to elucidate changes in the nascent proteome that occur during epidermal growth factor stimulation in migrating and invading cells. Annexin A2 was identified in this screen and subsequent examination of breast cancer cell lines revealed that Annexin A2 is specifically upregulated in estrogen receptor negative (ER-) cell lines. Furthermore, siRNA knockdown showed that Annexin A2 expression promotes the proliferation, wound healing and directional migration of breast cancer cells. In patients, Annexin A2 expression is increased in ER- breast cancer subtypes. Additionally, high Annexin A2 expression confers a higher probability of distant metastasis specifically for ER- patients. This work establishes a pivotal role of Annexin A2 in breast cancer progression and identifies Annexin A2 as a potential therapeutic target for the more aggressive and harder to treat ER- subtype.
Vasculopathy and Coagulopathy Associated with SARS-CoV-2 Infection
Authors: Labò Nazzarena , Ohnuki Hidetaka , Tosato Giovanna
Published: June 2020

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), has resulted in >500,000 deaths worldwide, including >125,000 deaths in the U.S. since its emergence in late December 2019 and June 2020. Neither curative anti-viral drugs nor a protective vaccine is currently available for the treatment and prevention of COVID-19. Recently, new clinical syndromes associated with coagulopathy and vasculopathy have emerged as a cause of sudden death and other serious clinical manifestations in younger patients infected with SARS-CoV-2 infection. Angiotensin converting enzyme 2 (ACE2), the receptor for SARS-CoV-2 and other coronaviruses, is a transmembrane protein expressed by lung alveolar epithelial cells, enterocytes, and vascular endothelial cells, whose physiologic role is to induce the maturation of angiotensin I to generate angiotensin 1-7, a peptide hormone that controls vasoconstriction and blood pressure. In this review, we provide the general context of the molecular and cellular mechanisms of SARS-CoV-2 infection with a focus on endothelial cells, describe the vasculopathy and coagulopathy syndromes in patients with SARS-CoV-2, and outline current understanding of the underlying mechanistic aspects.
Effect of cAMP Signaling Regulation in Osteogenic Differentiation of Adipose-Derived Mesenchymal Stem Cells
Authors: Rumiński Sławomir , Kalaszczyńska Ilona , Lewandowska-Szumieł Małgorzata
Published: June 2020

The successful implementation of adipose-derived mesenchymal stem cells (ADSCs) in bone regeneration depends on efficient osteogenic differentiation. However, a literature survey and our own experience demonstrated that current differentiation methods are not effective enough. Since the differentiation of mesenchymal stem cells (MSCs) into osteoblasts and adipocytes can be regulated by cyclic adenosine monophosphate (cAMP) signaling, we investigated the effects of cAMP activator, forskolin, and inhibitor, SQ 22,536, on the early and late osteogenic differentiation of ADSCs cultured in spheroids or in a monolayer. Intracellular cAMP concentration, protein kinase A (PKA) activity, and inhibitor of DNA binding 2 (ID2) expression examination confirmed cAMP up- and downregulation. cAMP upregulation inhibited the cell cycle and protected ADSCs from osteogenic medium (OM)-induced apoptosis. Surprisingly, the upregulation of cAMP level at the early stages of osteogenic differentiation downregulated the expression of osteogenic markers RUNX2, Osterix, and IBSP, which was more significant in spheroids, and it is used for the more efficient commitment of ADSCs into preosteoblasts, according to the previously reported protocol. However, cAMP upregulation in a culture of ADSCs in spheroids resulted in significantly increased osteocalcin production and mineralization. Thus, undifferentiated and predifferentiated ADSCs respond differently to cAMP pathway stimulation in terms of osteogenesis, which might explain the ambiguous results from the literature.
T-Cell Gene Therapy in Cancer Immunotherapy: Why It Is No Longer Just CARs on The Road
Authors: Crowther Michael D. , Svane Inge Marie , Met Özcan
Published: June 2020

T-cells have a natural ability to fight cancer cells in the tumour microenvironment. Due to thymic selection and tissue-driven immunomodulation, these cancer-fighting T-cells are generally low in number and exhausted. One way to overcome these issues is to genetically alter T-cells to improve their effectiveness. This process can involve introducing a receptor that has high affinity for a tumour antigen, with two promising candidates known as chimeric-antigen receptors (CARs), or T-cell receptors (TCRs) with high tumour specificity. This review focuses on the editing of immune cells to introduce such novel receptors to improve immune responses to cancer. These new receptors redirect T-cells innate killing abilities to the appropriate target on cancer cells. CARs are modified receptors that recognise whole proteins on the surface of cancer cells. They have been shown to be very effective in haematological malignancies but have limited documented efficacy in solid cancers. TCRs recognise internal antigens and therefore enable targeting of a much wider range of antigens. TCRs require major histocompatibility complex (MHC) restriction but novel TCRs may have broader antigen recognition. Moreover, there are multiple cell types which can be used as targets to improve the “off-the-shelf” capabilities of these genetic engineering methods.
Oxidative Inactivation of the Proteasome Augments Alveolar Macrophage Secretion of Vesicular SOCS3
Authors: Haggadone Mikel D. , Mancuso Peter , Peters-Golden Marc
Published: June 2020

Extracellular vesicles (EVs) contain a diverse array of molecular cargoes that alter cellular phenotype and function following internalization by recipient cells. In the lung, alveolar macrophages (AMs) secrete EVs containing suppressor of cytokine signaling 3 (SOCS3), a cytosolic protein that promotes homeostasis via vesicular transfer to neighboring alveolar epithelial cells. Although changes in the secretion of EV molecules—including but not limited to SOCS3—have been described in response to microenvironmental stimuli, the cellular and molecular machinery that control alterations in vesicular cargo packaging remain poorly understood. Furthermore, the use of quantitative methods to assess the sorting of cytosolic cargo molecules into EVs is lacking. Here, we utilized cigarette smoke extract (CSE) exposure of AMs as an in vitro model of oxidative stress to address these gaps in knowledge. We demonstrate that the accumulation of reactive oxygen species (ROS) in AMs was sufficient to augment vesicular SOCS3 release in this model. Using nanoparticle tracking analysis (NTA) in tandem with a new carboxyfluorescein succinimidyl ester (CFSE)-based intracellular protein packaging assay, we show that the stimulatory effects of CSE were at least in part attributable to elevated amounts of SOCS3 packaged per EV secreted by AMs. Furthermore, the use of a 20S proteasome activity assay alongside treatment of AMs with conventional proteasome inhibitors strongly suggest that ROS stimulated SOCS3 release via inactivation of the proteasome. These data demonstrate that tuning of AM proteasome function by microenvironmental oxidants is a critical determinant of the packaging and secretion of cytosolic SOCS3 protein within EVs.
Utilization of Carbon Dots Derived from Volvariella volvacea Mushroom for a Highly Sensitive Detection of Fe3+ and Pb2+ Ions in Aqueous Solutions
Authors: Zulfajri Muhammad , Liu Kang-Chen , Pu Yu-Hsin , Rasool Akhtar , Dayalan Sandhiya , Huang Genin Gary
Published: June 2020

In this study, Volvariella volvacea (VV) mushroom was utilized as a green carbon precursor to synthesize carbon dots (CDs) and applied as a fluorescent (FL) sensor to detect Fe3+ and Pb2+ ions. The VV-CDs showed a high photostability and FL properties with a quantum yield of about 11.5%. The VV-CDs exhibited an excitation-dependent emission manner, with an optimum emission wavelength at 440 nm excited at 360 nm. The VV-CDs were evaluated and shown to be facile and effective FL sensors for detecting Pb2+ and Fe3+ ions based on the FL quenching efficiency, demonstrating the special complex chelate between the metal ions and effective surface functional groups of VV-CDs. VV-CDs displayed high responses to Fe3+ and Pb2+ ions, with the linear relationship of 1-100 μM and limits of detection (LODs) of 12 and 16 nM for Pb2+ and Fe3+ ions, respectively. Furthermore, the FL sensor was validated with real water samples, showing very good spike recoveries.
Experimental Records from Blast Tests of Ten Reinforced Concrete Slabs
Authors: Mendonça Fausto B. , Urgessa Girum S. , Augusto Anselmo S. , Rocco José A. F. F.
Published: June 2020

The design and evaluation of structures subjected to blast loads has increased steadily since the 11 September 2001 terrorist attacks. While shock tube testing has filled some of the data gap by replicating blast waves in a controlled fashion, there is only scant field explosion data that is easily accessible for the structural engineering community for hypothesis testing or model validation. This paper summarizes experimental design, pre-test sensor verification, and data collection from 10 reinforced concrete slabs subjected to field explosions using a modest budget. The experimental record contains pressure, displacement, and acceleration measurements of each slab except in a few cases where the sensors have failed. The data is archived at George Mason Dataverse. Following detailed description of the experimental record for each slab, an example is provided in which the data can be utilized for finite element model verification.
Using the CHIRPS Dataset to Investigate Historical Changes in Precipitation Extremes in West Africa
Authors: Sacré Regis M. Didi , Mouhamed Ly , Kouakou Kouadio , Adeline Bichet , Arona Diedhiou , Houebagnon Saint. J. Coulibaly , Koffi Claude A. Kouadio , Talnan Jean H. Coulibaly , Salomon Obahoundje , Issiaka Savané
Published: June 2020

This study aims to provide improved knowledge and evidence on current (1986–2015) climate variation based on six rainfall indices over five West African countries (Senegal, Niger, Burkina Faso, Ivory Coast, and Benin) using the Climate Hazards Group InfraRed Precipitation with Station (CHIRPS) dataset. On average, precipitation has increased over the central Sahel and the western Sahel. This increase is associated with increase in the number of rainy days, longer wet spells and shorter dry spells. Over the Guinea Coast, the slight increase in precipitation is associated with an increase in the intensity of rainfall with a shorter duration of wet spells. However, these mean changes in precipitation are not all statistically significant and uniform within a country. While previous studies are focused on regional and sub-regional scales, this study contributes to deliver a climate information at a country level that is more relevant for decision making and for policy makers, and to document climate-related risks within a country to feed impact studies in key sectors of the development, such as agriculture and water resources.
HPLC with Fluorescence Detection for Determination of Bisphenol A in Canned Vegetables: Optimization, Validation and Application to Samples from Portuguese and Spanish Markets
Authors: Vilarinho Fernanda , Lestido-Cardama Antia , Sendón Raquel , Rodríguez Bernaldo de Quirós Ana , Vaz Maria de Fátima , Sanches-Silva Ana
Published: June 2020

Bisphenol A (BPA) is one of the chemicals used to produce both polycarbonate plastics and epoxy resin coatings. Research has shown that small amounts of BPA can migrate into the foods and beverages enclosed in these types of containers. In this research, an analytical method based on high-performance liquid chromatography with fluorescence detection (HPLC-FLD) was developed and validated for the determination of BPA in canned vegetables. The results were confirmed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was performed, to identify the coating material of each tin can. Nineteen cans of vegetables were taken as study samples (eleven samples from the Spanish market, and eight samples from the Portuguese market). Excellent linear correlation (r2 = 0.9999) was observed over the range of 0.01 to 0.25 mg/L. Limit of detection (LOD) and limit of quantification (LOQ) values were calculated to be 0.005 mg/kg and 0.01 mg/kg, respectively. Good recoveries, between 72% and 90% were obtained at three different levels of concentration (RSD% = 4.6). BPA was not detected in the samples. The proposed HPLC-FLD was found to be suitable for the determination of BPA in canned vegetables.
Wood Surface Modification—Classic and Modern Approaches in Wood Chemical Treatment by Esterification Reactions
Authors: Teacă Carmen-Alice , Tanasă Fulga
Published: June 2020

Wood surface modification is a comprehensive concept which, in time, turned out to be as successful as challenging when it comes to improve the resistance of wood during its life cycle in both indoor and outdoor applications. The initial approaches have aimed at simple methods with immediate results. Nowadays, the paradigm has slightly changed due to the scientific and technical advances, and some methods has become intermediate stages in more complex processes, after being used, for long time, as stand-alone procedures. The esterification was employed as a convenient method for wood surface modification due to the high amount of free hydroxyl groups available at the surface of wood and other lignocellulosic materials. Therefore, different esterification approaches were tested: activated condensation with carboxylic acids (monocarboxylic, as well as dicarboxylic acids, fatty acids, etc.) in the presence of condensation activating agents (such as trifluoroacetic anhydride); reaction with β-halogen-substituted carboxylic acids; esterification using carboxylic acids derivatives (acyl chlorides, anhydrides) or even multifunctional carboxylic acids (i.e., tricine). Thus, wood with improved dimensional stability and weathering resilience, higher fire resistance, enhanced hydrophobic character, and mechanical durability was obtained. This paper offers an overview of some of the most recent advances reported in the field, presented in a systematic manner, using the type of reaction as classification criterion. The main improvements will be outlined in a critical assessment in order to provide an useful tool for a wise choice in future applications.
Surface Treatments Solutions to Green Tribology
Authors: Igartua Amaya , Mendoza Gemma , Fernandez Xana , Zabala Borja , Alberdi Alberto , Bayon Raquel , Aranzabe Ana
Published: June 2020

The objective of this paper is to highlight the need to combine lifecycle environmental assessment with durability evaluation (tribology and engine tests) to evaluate the potential of surface technologies to contribute to the green deal, in order to make Europe the first climate-neutral continent. Tribology is a scientific discipline that allows one to understand the system reaction to friction and wear. Tribological testing machines are prepared to measure friction at the laboratory level to minimize the wear and heat dissipation of two bodies in relative movement, thus improving the energy efficiency and minimizing CO2 emissions. In this paper, different surface technologies, such as high-velocity oxyfuel (HVOF), physical vapor deposition (PVD), and clean Cr electrolytic processes, are analyzed as promising surface technology solutions from both performance and environmental impact perspectives to replace harmful Cr(VI) coatings. The tribology simulates the working conditions of the real system at the laboratory level, reproducing the failure mechanism and facilitating the laboratory screening of the energy efficiency and durability of materials solutions for certain tribological systems—in this case, engine components. The tribological test results give information about the behavior of materials, while the engine tests gives information about the behavior of components. In this paper, the environmental impact of the production process of the coatings is also analyzed. Two hard chrome processes are compared, demonstrating that by controlling the production process it is possible to significantly reduce the environmental impact of the chrome-plated process, minimizing the environmental impact to that of PVD coatings. The environmental impact of the tested HVOF process is lower than traditional Cr(VI)-plated coatings but higher than PVD coatings. Combining the information from the lifecycle assessment (LCA) and tribological studies, it is possible to assess both the performance and the environmental impact of the surface treatments. This methodology is a tool to that can be used minimize CO2 emissions at the design phase to improve the energy efficiency of products and processes.
Evaluation of Functionalized Coatings for the Prevention of Ice Accretion by Using Icing Wind Tunnel Tests
Authors: Rivero Pedro J. , Rodriguez Rafael J. , Larumbe Silvia , Monteserín María , Martín Francisco , García Amador , Acosta Carolina , Clemente María José , García Paloma , Mora Julio , Agüero Alina
Published: June 2020

Ice accretion presents serious safety issues, as airplanes are exposed to supercooled water droplets both on the ground and while flying through clouds in the troposphere. Prevention of icing is a main concern for both developers and users of aircraft. The successful solution of this problem implies the combination of active and passive methods and the use of advanced sensors for early detection of icing and monitoring of ice accretion and de-icing processes. This paper focuses on the development of passive solutions. These include advanced anti-icing coatings deposited by a variety of chemical methods including sol-gel, advanced paints based on polyester combined with fluorinated derivatives and applied by electrostatic spray deposition and conventional silicone-based paints modified by adding alumina nanoparticles. Water contact angle has been measured in all cases, demonstrating the hydrophobic character of the coatings. An ice accretion test has been carried out in a laboratory scale icing wind tunnel (IWT) located in a cold climate chamber. Three different studies have been undertaken: ice accretion measurement, durability of the anti-icing behavior after several icing/de-icing cycles and ice adhesion testing by means of the double lap shear test (DLST) methodology. All the studied coatings have shown significant anti-icing behavior which has been maintained, in some cases, beyond 25 cycles. Although these results are still far from any possible application for aeronautic components, they provide interesting insights for new developments and validate the laboratory scale tests.
Enhanced Tribological Properties of LA43M Magnesium Alloy by Ni60 Coating via Ultra-High-Speed Laser Cladding
Authors: Asghar Osama , Li-Yan Lou , Yasir Muhammad , Chang-Jiu Li , Cheng-Xin Li
Published: June 2020

Laser modification techniques have been widely adopted in the field of surface engineering. Among these modified techniques, ultra-high-speed laser cladding is trending most nowadays to fabricate wear-resistant surfaces. The main purpose of this research is to provide a detailed insight of ultra-high-speed laser cladding of hard Ni60 alloy on LA43M magnesium alloy to enhance its surface mechanical properties. Multiple processing parameters were investigated to obtain the optimal result. The synthesized coating was studied microstructurally by field emission scanning electron microscopy (FESEM) equipped with an energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The microhardness and wear resistance of the Ni60 coating were analyzed under Vickers hardness and pin on disc tribometer respectively. The obtained results show that the dense Ni60 coating was fabricated with a thickness of 300 μm. No cracks and porosities were detected in cross-sectional morphology. The Ni60 coating was mainly composed of γ-Ni and hard phases (chromium carbides and borides). The average microhardness of coating was recorded as 948 HV0.3, which is approximately eight times higher than that of the substrate. Meanwhile, the Ni60 coating exhibited better wear resistance than the substrate, which was validated upon the wear loss and wear mechanism. The wear loss recorded for the substrate was 6.5 times higher than that of the coating. The main wear mechanism in the Ni60 coating was adhesive while the substrate showed abrasive characteristics.
CeO2 Containing Thin Films as Bioactive Coatings for Orthopaedic Implants
Authors: Prefac Georgiana-Alexandra , Milea Marina-Larisa , Vadureanu Andreea-Mihaela , Muraru Sorin , Dobrin Daniela-Ileana , Isopencu Gabriela-Olimpia , Jinga Sorin-Ion , Raileanu Mina , Bacalum Mihaela , Busuioc Cristina
Published: June 2020

Due to the fact of their ability to bond with human’s hard tissue, bioglasses have gained interest in the biomedical field with certain purposes regarding their usage in the replacement, healing or repair of bones. In the form of thin films, they trigger an increase in biocompatibility for the inert supports after implantation, based on surface engineering to ensure osteoinduction. For that, this research is focused on obtaining coatings based on cerium-enriched bioglass to generate bioactive and potential additional antimicrobial and antioxidant properties. The addressed oxide system was a novel and complex one, 46.10 SiO2–2.60 P2O5–16.90 CaO–10.00 MgO–19.40 Na2O–5.00 CeO2 (mol%), while two different synthesis methods, laser ablation and spin coating, were tackled comparatively. In the case of the first technique, substrate temperature was selected as variable parameter (room temperature or 300 °C). After conducting a complex characterization, films’ deposition was validated, their bioactive behaviour was proven by the formation of calcium phosphate after immersion in simulated body fluid for four weeks, while the impact exerted on the tested human fibroblast BJ cells (ATCC, CRL-2522) confirmed the applicative potential.
Oxygen Inhomogeneity and Reversibility in Single Crystal LaNiO3−δ
Authors: Zheng Hong , Wang Bi-Xia , Phelan D. , Zhang Junjie , Ren Yang , Krogstad M. , Rosenkranz S. , Osborn R. , Mitchell J.
Published: June 2020

LaNiO3−δ single crystals have been obtained via high pressure floating zone growth under 149 bar of oxygen pressure. We find a radial gradient in the magnetic properties of specimens extracted from the as-grown boule, which we correlate with the appearance of ordered oxygen vacancy structures. This radial oxygen inhomogeneity has been characterized systematically using a combination of magnetization and X-ray scattering measurements. We establish the presence of rhombohedral ( R 3 ¯ c ), oxygen stoichiometric specimens at the periphery of the boule and the presence of a dilute concentration of ordered oxygen-deficient orthorhombic La2Ni2O5 in the center. Furthermore, we demonstrate that the as-grown, oxygen-deficient central regions of the crystal can be annealed under high oxygen pressure, without loss of crystallinity, into fully oxygenated LaNiO3, recovering magnetic properties that are characteristic of stoichiometric specimens from the exterior region of the crystal. Thus, single crystals of LaNiO3−δ possess oxygen content that can be reversibly modified under oxidizing and reducing conditions.
The Importance of Genomics for Deciphering the Invasion Success of the Seagrass Halophila stipulacea in the Changing Mediterranean Sea
Authors: Tsakogiannis Alexandros , Manousaki Tereza , Anagnostopoulou Vasileia , Stavroulaki Melanthia , Apostolaki Eugenia T.
Published: June 2020

The Mediterranean Sea is subject to pressures from biological invasion due to coastal anthropic activities and global warming, which potentially modify its biogeography. The Red Sea tropical seagrass Halophila stipulacea entered the Eastern Mediterranean over a century ago, and its occurrence is expanding towards the northwest. Here, we highlight the importance of genomics for deciphering the evolutionary and ecological procedures taking place during the invasion process of H. stipulacea and review the relatively sparse genetic information available for the species to date. We report the first draft whole-genome sequencing of a H. stipulacea individual from Greece, based on Illumina Sequencing technology. A comparison of the Internal Transcribed Spacer (ITS) regions revealed a high divergence of the herein sequenced individual compared to Mediterranean populations sequenced two decades ago, rendering further questions on the evolutionary processes taking place during H. stipulacea adaptation in the invaded Mediterranean Sea. Our work sets the baseline for a future analysis of the invasion genomic of the focal species.
Experimental Force Data of a Restrained ROV under Waves and Current
Authors: Gabl Roman , Davey Thomas , Cao Yu , Li Qian , Li Boyang , Walker Kyle L. , Giorgio-Serchi Francesco , Aracri Simona , Kiprakis Aristides , Stokes Adam A. , Ingram David M.
Published: June 2020

Hydrodynamic forces are an important input value for the design, navigation and station keeping of underwater Remotely Operated Vehicles (ROVs). The experiment investigated the forces imparted by currents (with representative real world turbulence) and waves on a commercially available ROV, namely the BlueROV2 (Blue Robotics, Torrance, USA). Three different distances of a simplified cylindrical obstacle (shading effects) were investigated in addition to the free stream cases. Eight tethers held the ROV in the middle of the 2 m water depth to minimise the influence of the support structure without completely restricting the degrees of freedom (DoF). Each tether was equipped with a load cell and small motions and rotations were documented with an underwater video motion capture system. The paper describes the experimental set-up, input values (current speed and wave definitions) and initial processing of the data. In addition to the raw data, a processed dataset is provided, which includes forces in all three main coordinate directions for each mounting point synchronised with the 6DoF results and the free surface elevations. The provided dataset can be used as a validation experiment as well as for testing and development of an algorithm for position control of comparable ROVs.
Cardiovascular Adaptations to Four Months Training in Middle-Aged Amateur Long-Distance Skiers
Authors: Grzebisz Natalia
Published: June 2020

Cross-country skiing has a positive effect on health. However, without an individual, thoughtful, and professional plan, it can cause irreversible health problems from overload and injury. The impact of exercise on results is well understood within the group of professional athletes. However, this remains unknown within the group of amateur cross-country skiers and marathon runners—in particular, the impact of the summer preparation period in which training loads performed in the oxygen zone combined with resistance training dominate. The aim of this study was to assess changes in the cardiovascular capacity and body mass composition of male cross-country skiers in the preparation period of their macrocycle. Variables were analyzed using basic descriptive statistics: mean and standard deviation (SD). To compare the results from both measurements (initial and final) the paired Wilcoxon test was used. A statistically significant increase was noted in maximum oxygen uptake and maximum minute ventilation, and a decrease in body fat content, maximum lactate concentration and lactate threshold, and heart rate on anaerobic threshold. Research indicated that in the amateur group increases similar to those in top competitors were achieved in the parameters tested, but the initial level was often significantly lower.
Clinical Perspective and Translational Oncology of Liquid Biopsy
Authors: Fernández-Lázaro Diego , García Hernández Juan Luis , Caballero García Alberto , Caballero del Castillo Aurora , Villaverde Hueso María , Cruz-Hernández Juan Jesús
Published: June 2020

The term liquid biopsy (LB) refers to the study of circulating tumor cells, circulating tumors nucleic acids free of cells or contained in exosomes, and information about platelets associated with tumors. LB can be performed in different biofluids and allows the limitations of tissue biopsy to be overcome offering possibilities of tumor identification reflecting in real time tumor heterogeneity. In addition, LB allows screening and early detection of cancer, real-time monitoring of therapy, stratification and therapeutic intervention, a therapeutic target and resistance mechanism, and a risk of metastatic relapse. Currently, LB has been shown to be effective for its application in different types of tumors including lung, colorectal, prostate, melanoma, breast and pancreatic cancer, by the determination and identification of biomarkers that with a high probability have the potential to change the way in which medical oncology could predict the course of the disease. These biomarkers make it possible to capture the heterogeneity of the cancer, monitor its clonal evolution, indicate new treatments or retreatments and evaluate the responses to different evolutionary and/or therapeutic pressures in the cancer disease.
A Survey of the Selenium Ecosystem
Authors: García Boni , Gallego Micael , Gortázar Francisco , Munoz-Organero Mario
Published: June 2020

Selenium is often considered the de-facto standard framework for end-to-end web testing nowadays. It allows practitioners to drive web browsers (such as Chrome, Firefox, Edge, or Opera) in an automated fashion using different language bindings (such as Java, Python, or JavaScript, among others). The term ecosystem, referring to the open-source software domain, includes various components, tools, and other interrelated elements sharing the same technological background. This article presents a descriptive survey aimed to understand how the community uses Selenium and its ecosystem. This survey is structured in seven categories: Selenium foundations, test development, system under test, test infrastructure, other frameworks, community, and personal experience. In light of the current state of Selenium, we analyze future challenges and opportunities around it.
Polarization-Charge Inversion at Al2O3/GaN Interfaces through Post-Deposition Annealing
Authors: Kim Kwangeun , Jang Jaewon
Published: June 2020

The effects of post-deposition annealing (PDA) on the formation of polarization-charge inversion at ultrathin Al2O3/Ga-polar GaN interfaces are assessed by the analysis of energy band bending and measurement of electrical conduction. The PDA-induced positive interface charges form downward energy band bending at the Al2O3/GaN interfaces with polarization-charge inversion, which is analyzed using X-ray photoelectron spectroscopy. Net charge and interface charge densities at the Al2O3/GaN interfaces are estimated after PDA at 500 °C, 700 °C, and 900 °C. The PDA temperatures affect the formation of charge densities. That is, the charge density increases up to 700 °C and then decreases at 900 °C. Electrical characteristics of GaN Schottky diodes with ultrathin Al2O3 layers exhibit the passivation ability of the Al2O3 surface layer and the effects of polarization-charge inversion through PDA. This result can be applied to improvement in GaN-based electronic devices where surface states and process temperature work important role in device performance.
An Intelligent Fuzzy Logic-Based Content and Channel Aware Downlink Scheduler for Scalable Video over OFDMA Wireless Systems
Authors: Omiyi Peter E. , Nasralla Moustafa M. , Rehman Ikram Ur , Khan Nabeel , Martini Maria G.
Published: June 2020

The recent advancements of wireless technology and applications make downlink scheduling and resource allocations an important research topic. In this paper, we consider the problem of downlink scheduling for multi-user scalable video streaming over orthogonal frequency division multiple access (OFDMA) channels. The video streams are precoded using a scalable video coding (SVC) scheme. We propose a fuzzy logic-based scheduling algorithm, which prioritises the transmission to different users by considering video content, and channel conditions. Furthermore, a novel analytical model and a new performance metric have been developed for the performance analysis of the proposed scheduling algorithm. The obtained results show that the proposed algorithm outperforms the content-blind/channel aware scheduling algorithms with a gain of as much as 19% in terms of the number of supported users. The proposed algorithm allows for a fairer allocation of resources among users across the entire sector coverage, allowing for the enhancement of video quality at edges of the cell while minimising the degradation of users closer to the base station.
Modeling of Clos Switching Structures with Dynamically Variable Number of Active Switches in the Spine Stage
Authors: Głąbowski Mariusz , Sobieraj Maciej , Stasiak Maciej , Dominik Stasiak Michał
Published: June 2020

This article proposes a new analytical model of a switching structure using a Clos network topology. The assumption is that, in the structure under consideration, it is possible to switch off temporarily a certain number of spine switches (those in the middle stage of the switching fabric) depending on the current intensity of the offered traffic to reduce power consumption. The solution presented in the article can be used in present-day multiservice switching fabrics and in networks connecting servers in data centers. The developed analytical model allows the value of blocking probabilities for different stream classes of multiservice traffic to be evaluated in switching structures (switching fabrics) with a variable number of switches in the middle stage. The results obtained on the basis of the analytical model are compared with the results obtained as a result of relevant simulation experiments for a selected structure of the switching fabric. The study confirms high accuracy of the proposed model. This model can be used in further works to evaluate the effectiveness of energy-saving switching fabrics and the networks of data centers, as well as to construct energy-saving control algorithms that would control these switching structures, that is, algorithms that would change the topology of the switching fabric depending on changes in the offered traffic.
Habitat Models of Focal Species Can Link Ecology and Decision-Making in Sustainable Forest Management
Authors: Lõhmus Asko , Kont Raido , Runnel Kadri , Vaikre Maarja , Remm Liina
Published: June 2020

A fundamental problem of sustainability is how to reduce the double complexity of ecological and social systems into simple operational terms. We highlight that the conservation concept of focal species (selected species sensitive to a set of anthropogenic threats to their habitat) links multiple issues of ecological sustainability, and their habitat models can provide a practical tool for solving these issues. A review of the literature shows that most spatial modeling of focal species focuses on vertebrates, lacks the aspect of aquatic and soil habitats, and has been slow in the uptake by actual management planning. We elaborate on a deductive modeling approach that first generalizes the main influential dimensions of habitat change (threats), which are then parameterized as habitat quality estimates for focal species. If built on theoretical understanding and properly scaled, the maps produced with such models can cost-effectively describe the dynamics of ecological qualities across forest landscapes, help set conservation priorities, and reflect on management plans and practices. The models also serve as ecological hypotheses on biodiversity and landscape function. We illustrate this approach based on recent additions to the forest reserve network in Estonia, which addressed the insufficient protection of productive forest types. For this purpose, mostly former production forests that may require restoration were set aside. We distinguished seven major habitat dimensions and their representative taxa in these forests and depicted each dimension as a practical stand-scale decision tree of habitat quality. The model outcomes implied that popular stand-structural targets of active forest restoration would recover passively in reasonable time in these areas, while a critically degraded condition (loss of old trees of characteristic species) required management beyond reserve borders. Another hidden issue revealed was that only a few stands of consistently low habitat quality concentrated in the landscape to allow cost-efficient restoration planning. We conclude that useful habitat models for sustainable forest management have to balance single-species realism with stakeholder expectations of meaningful targets and scales. Addressing such social aspects through the focal species concept could accelerate the adoption of biodiversity distribution modeling in forestry.
Exploitation of Agro-Industrial Waste as Potential Source of Bioactive Compounds for Aquaculture
Authors: Leyva-López Nayely , Lizárraga-Velázquez Cynthia E. , Hernández Crisantema , Sánchez-Gutiérrez Erika Y.
Published: June 2020

The agroindustry generates a large amount of waste. In postharvest, food losses can reach up to 50%. This waste represents a source of contamination of soil, air, and bodies of water. This represents a problem for the environment as well as for public health. However, this waste is an important source of bioactive compounds, such as phenolic compounds, terpenes, and β-glucans, among others. Several biological activities have been attributed to these compounds; for example, antioxidant, antimicrobial, gut microbiota, and immune system modulators. These properties have been associated with improvements in health. Recently, the approach of using these bioactive compounds as food additives for aquaculture have been addressed, where it is sought that organisms, in addition to growing, preserve their health and become disease resistant. The exploitation of agro-industrial waste as a source of bioactive compounds for aquaculture has a triple objective—to provide added value to production chains, reduce pollution, and improve the well-being of organisms through nutrition. However, to make use of the waste, it is necessary to revalue them, mainly by determining their biological effects in aquaculture organisms. The composition of bioactive compounds of agro-industrial wastes, their biological properties, and their application in aquaculture will be addressed here.