bluuebunny/crossref_metadata_2025 huggingface dataset:
Deubiquitination Reactions on the Proteasome for Proteasome Versatility
Authors: Shin Ji Yeong , Muniyappan Srinivasan , Tran Non-Nuoc , Park Hyeonjeong , Lee Sung Bae , Lee Byung-Hoon
Published: July 2020

The 26S proteasome, a master player in proteolysis, is the most complex and meticulously contextured protease in eukaryotic cells. While capable of hosting thousands of discrete substrates due to the selective recognition of ubiquitin tags, this protease complex is also dynamically checked through diverse regulatory mechanisms. The proteasome’s versatility ensures precise control over active proteolysis, yet prevents runaway or futile degradation of many essential cellular proteins. Among the multi-layered processes regulating the proteasome’s proteolysis, deubiquitination reactions are prominent because they not only recycle ubiquitins, but also impose a critical checkpoint for substrate degradation on the proteasome. Of note, three distinct classes of deubiquitinating enzymes—USP14, RPN11, and UCH37—are associated with the 19S subunits of the human proteasome. Recent biochemical and structural studies suggest that these enzymes exert dynamic influence over proteasome output with limited redundancy, and at times act in opposition. Such distinct activities occur spatially on the proteasome, temporally through substrate processing, and differentially for ubiquitin topology. Therefore, deubiquitinating enzymes on the proteasome may fine-tune the degradation depending on various cellular contexts and for dynamic proteolysis outcomes. Given that the proteasome is among the most important drug targets, the biology of proteasome-associated deubiquitination should be further elucidated for its potential targeting in human diseases.
Targeting Epigenetic Modifications in Uveal Melanoma
Authors: Chokhachi Baradaran Pooneh , Kozovska Zuzana , Furdova Alena , Smolkova Bozena
Published: July 2020

Uveal melanoma (UM), the most common intraocular malignancy in adults, is a rare subset of melanoma. Despite effective primary therapy, around 50% of patients will develop the metastatic disease. Several clinical trials have been evaluated for patients with advanced UM, though outcomes remain dismal due to the lack of efficient therapies. Epigenetic dysregulation consisting of aberrant DNA methylation, histone modifications, and small non-coding RNA expression, silencing tumor suppressor genes, or activating oncogenes, have been shown to play a significant role in UM initiation and progression. Given that there is no evidence any approach improves results so far, adopting combination therapies, incorporating a new generation of epigenetic drugs targeting these alterations, may pave the way for novel promising therapeutic options. Furthermore, the fusion of effector enzymes with nuclease-deficient Cas9 (dCas9) in clustered regularly interspaced short palindromic repeats (CRISPR) associated protein 9 (Cas9) system equips a potent tool for locus-specific erasure or establishment of DNA methylation as well as histone modifications and, therefore, transcriptional regulation of specific genes. Both, CRISPR-dCas9 potential for driver epigenetic alterations discovery, and possibilities for their targeting in UM are highlighted in this review.
Cellular and Molecular Aspects of Blood Cell–Endothelium Interactions in Vascular Disorders
Authors: Wautier Jean-Luc , Wautier Marie-Paule
Published: July 2020

In physiology and pathophysiology the molecules involved in blood cell–blood cell and blood cell–endothelium interactions have been identified. Platelet aggregation and adhesion to the walls belonging to vessels involve glycoproteins (GP), GP llb and GP llla and the GP Ib–IX–V complex. Red blood cells (RBCs) in normal situations have little interaction with the endothelium. Abnormal adhesion of RBCs was first observed in sickle cell anemia involving vascular cell adhesion molecule (VCAM)-1, α4β1, Lu/BCAM, and intercellular adhesion molecule (ICAM)-4. More recently RBC adhesion was found to be increased in retinal-vein occlusion (RVO) and in polycythemia vera (PV). The molecules which participate in this process are phosphatidylserine and annexin V in RVO, and phosphorylated Lu/BCAM and α5 laminin chain in PV. The additional adhesion in diabetes mellitus occurs due to the glycated RBC band 3 and the advanced glycation end-product receptors. The multiligand receptor binds advanced glycation end products (AGEs) or S100 calgranulins, or β-amyloid peptide. This receptor for advanced glycation end products is known as RAGE. The binding to RAGE-activated endothelial cells leads to an inflammatory reaction and a prothrombotic state via NADPH activation and altered gene expression. RAGE blockade is a potential target for drugs preventing the deleterious consequences of RAGE activation.
Investigating the Mullins Effect and Energy Dissipation in Magnetorheological Polyurethane Elastomers
Authors: Elías-Zúñiga Alex , Palacios-Pineda Luis M. , Perales-Martínez Imperio A. , Martínez-Romero Oscar , Olvera-Trejo Daniel , Jiménez-Cedeño Isaac H.
Published: July 2020

The aim of this article was to investigate the mechanical performance of magnetorheological polyurethane elastomers reinforced with different concentrations of carbonyl iron microparticles (CIPs) in which stress softening, energy dissipation, residual strains, microparticles orientation, and magnetic flux density effects will be considered. Other aspects, such as the determination of the dissipated energy during cyclic loading and unloading, were investigated by considering a pseudo-elastic network model that takes into account residual strains, magnetic field intensity, and the isotropic and anisotropic material behavior. Theoretical predictions confirmed that the material shear modulus becomes sensitive not only for higher concentrations of CIPs added into the elastomer material matrix, but also to the magnetic flux intensity that induces attractive forces between CIPs and to the strong bonds between these and the elastomer matrix. It was also found that the addition of CIPs when embedded into the polymer matrix with a predefined orientation enhances the material shear modulus as well as its capacity to dissipate energy when subjected to magnetic flux density in loading and unloading directions.
Microbial Virulence Factors
Authors: Leitão Jorge H.
Published: July 2020

Microbial virulence factors encompass a wide range of molecules produced by pathogenic microorganisms, enhancing their ability to evade their host defenses and cause disease [...]
Rearrangement of the Cellulose-Enriched Cell Wall in Flax Phloem Fibers over the Course of the Gravitropic Reaction
Authors: Ibragimova Nadezda , Mokshina Natalia , Ageeva Marina , Gurjanov Oleg , Mikshina Polina
Published: July 2020

The plant cell wall is a complex structure consisting of a polysaccharide network. The rearrangements of the cell wall during the various physiological reactions of plants, however, are still not fully characterized. Profound changes in cell wall organization are detected by microscopy in the phloem fibers of flax (Linum usitatissimum) during the restoration of the vertical position of the inclined stems. To characterize the underlying biochemical and structural changes in the major cell wall polysaccharides, we compared the fiber cell walls of non-inclined and gravistimulated plants by focusing mainly on differences in non-cellulosic polysaccharides and the fine cellulose structure. Biochemical analysis revealed a slight increase in the content of pectins in the fiber cell walls of gravistimulated plants as well as an increase in accessibility for labeling non-cellulosic polysaccharides. The presence of galactosylated xyloglucan in the gelatinous cell wall layer of flax fibers was demonstrated, and its labeling was more pronounced in the gravistimulated plants. Using solid state NMR, an increase in the crystallinity of the cellulose in gravistimulated plants, along with a decrease in cellulose mobility, was demonstrated. Thus, gravistimulation may affect the rearrangement of the cell wall, which can enable restoration in a vertical position of the plant stem.
Clinical Implementation of Predictive Models Embedded within Electronic Health Record Systems: A Systematic Review
Authors: Lee Terrence C. , Shah Neil U. , Haack Alyssa , Baxter Sally L.
Published: July 2020

Predictive analytics using electronic health record (EHR) data have rapidly advanced over the last decade. While model performance metrics have improved considerably, best practices for implementing predictive models into clinical settings for point-of-care risk stratification are still evolving. Here, we conducted a systematic review of articles describing predictive models integrated into EHR systems and implemented in clinical practice. We conducted an exhaustive database search and extracted data encompassing multiple facets of implementation. We assessed study quality and level of evidence. We obtained an initial 3393 articles for screening, from which a final set of 44 articles was included for data extraction and analysis. The most common clinical domains of implemented predictive models were related to thrombotic disorders/anticoagulation (25%) and sepsis (16%). The majority of studies were conducted in inpatient academic settings. Implementation challenges included alert fatigue, lack of training, and increased work burden on the care team. Of 32 studies that reported effects on clinical outcomes, 22 (69%) demonstrated improvement after model implementation. Overall, EHR-based predictive models offer promising results for improving clinical outcomes, although several gaps in the literature remain, and most study designs were observational. Future studies using randomized controlled trials may help improve the generalizability of findings.
Exosome: A New Player in Translational Nanomedicine
Authors: Aheget Houssam , Tristán-Manzano María , Mazini Loubna , Cortijo-Gutierrez Marina , Galindo-Moreno Pablo , Herrera Concha , Martin Francisco , Marchal Juan Antonio , Benabdellah Karim
Published: July 2020

Summary: Exosomes are extracellular vesicles released by the vast majority of cell types both in vivo and ex vivo, upon the fusion of multivesicular bodies (MVBs) with the cellular plasma membrane. Two main functions have been attributed to exosomes: their capacity to transport proteins, lipids and nucleic acids between cells and organs, as well as their potential to act as natural intercellular communicators in normal biological processes and in pathologies. From a clinical perspective, the majority of applications use exosomes as biomarkers of disease. A new approach uses exosomes as biologically active carriers to provide a platform for the enhanced delivery of cargo in vivo. One of the major limitations in developing exosome-based therapies is the difficulty of producing sufficient amounts of safe and efficient exosomes. The identification of potential proteins involved in exosome biogenesis is expected to directly cause a deliberate increase in exosome production. In this review, we summarize the current state of knowledge regarding exosomes, with particular emphasis on their structural features, biosynthesis pathways, production techniques and potential clinical applications.
Effectiveness, Timing and Procedural Aspects of Cognitive Behavioral Therapy after Deep Brain Stimulation for Therapy-Resistant Obsessive Compulsive Disorder: A Systematic Review
Authors: Görmezoğlu Meltem , Bouwens van der Vlis Tim , Schruers Koen , Ackermans Linda , Polosan Mircea , Leentjens Albert F.G.
Published: July 2020

Background and aim: Deep brain stimulation (DBS) is an effective treatment for patients with severe therapy-resistant obsessive-compulsive disorder (OCD). After initiating DBS many patients still require medication and/or behavioral therapy to deal with persisting symptoms and habitual behaviors. The clinical practice of administering postoperative cognitive behavioral therapy (CBT) varies widely, and there are no clinical guidelines for this add-on therapy. The aim of this review is to assess the efficacy, timing and procedural aspects of postoperative CBT in OCD patients treated with DBS. Method: Systematic review of literature. Results: The search yielded 5 original studies, one case series and three reviews. Only two clinical trials have explicitly focused on the effectiveness of CBT added to DBS in patients with therapy-resistant OCD. These two studies both showed effectiveness of CBT. However, they had a distinctly different design, very small sample sizes and different ways of administering the therapy. Therefore, no firm conclusions can be drawn or recommendations made for administering CBT after DBS for therapy-resistant OCD. Conclusion: The effectiveness, timing and procedural aspects of CBT added to DBS in therapy-resistant OCD have hardly been studied. Preliminary evidence indicates that CBT has an added effect in OCD patients being treated with DBS. Since the overall treatment effect is the combined result of DBS, medication and CBT, future trials should be designed in such a way that they allow quantification of the effects of these add-on therapies in OCD patients treated with DBS. Only in this way information can be gathered that contributes to the development of an algorithm and clinical guidelines for concomittant therapies to optimize treatment effects in OCD patients being treated with DBS.
Is Basal Cell Carcinoma an Itchy Tumor? Clinical Characteristics of Itch in Basal Cell Carcinoma
Authors: Chlebicka Iwona , Stefaniak Aleksandra A , Matusiak Łukasz , Szepietowski Jacek C
Published: July 2020

In common knowledge, basal cell carcinoma (BCC) is known to be asymptomatic, but in clinical practice, at least some patients complain of itching. The present study group comprised of 180 patients with histologically confirmed BCC. Detailed information on demographics, clinical history, and physical findings was recorded. Moreover, various clinical features of itch (including intensity, localization, quality, descriptors) and the most common factors responsible for its aggravation or alleviation were examined. The itch was present in 21.1% of patients with BCC and was limited to the tumor. The mean intensity of the itch was 3.1 ± 1.2 points (Numerical Rating Scale), indicating moderate itch intensity. Among the patients, 22.4% reported that itching occurred constantly, every day. BCC-associated itch seems to be moderately frequent, although being a seemingly underestimated problem among patients with BCC.
A New Algorithm to Estimate Diffuse Attenuation Coefficient from Secchi Disk Depth
Authors: Castillo-Ramírez Alejandra , Santamaría-del-Ángel Eduardo , González-Silvera Adriana , Frouin Robert , Sebastiá-Frasquet María-Teresa , Tan Jing , Lopez-Calderon Jorge , Sánchez-Velasco Laura , Enríquez-Paredes Luis
Published: July 2020

The vertical diffuse attenuation coefficient Kd (PAR) is used for calculating the euphotic zone, the first optical depth that is important for primary productivity models. Currently, Kd (PAR) can be estimated using an irradiometer or a Secchi disk (SD). The main objective of this work is to define a model that can be applied to a wide range of optical marine conditions to estimate Kd (PAR) by SD. We used irradiance profiles and SD depth (ZSD) from 679 stations in various marine regions. Three parametric models were developed, and their statistical performance was evaluated in view of previous approaches reported and remote sensing data. The best results were obtained with an adaptive model representing three cases: clear-water, turbid-water, and a transition zone (R2 = 0.965, MAE = 0.083, RMSD = 0.239, BIAS = 0.01, and MPI = 0.854). Previous models considering a single optical depth figure at which the SD disappears did not capture the marine optical complexity. Our classification of 113 stations with spectral absorption data into Jerlov water types indicated that no unique correspondence existed between estimated Kd (PAR) and water type, making it ambiguous to associate compatible inherent optical properties and chlorophyll with ZSD. Although obtaining Kd (PAR) from ZSD is simple/low-cost, care should be taken in the methodology used to measure ZSD to ensure consistent results across different optical marine conditions.
Participatory Mapping of Cultural Ecosystem Services in Madrid: Insights for Landscape Planning
Authors: García-Díez Víctor , García-Llorente Marina , González José A.
Published: July 2020

Cultural ecosystem services are gaining increasing attention in the scientific literature, despite the conceptual and methodological difficulties associated with their assessment. We used a participatory GIS method to map and assess three cultural ecosystem services, namely, (a) outdoor recreation, (b) aesthetic enjoyment, and (c) sense of place, in the Madrid region (Spain). The main goal of the study was to identify cultural ecosystem service hotspots in the region and to explore the relationships among the three ecosystem services mapped. We developed a Maptionnaire online questionnaire asking participants to locate places that they associate with these three ecosystem services and their main reasons for choosing those places on a map. We collected 580 complete questionnaires with 1710 location points (807 for outdoor recreation, 506 for aesthetic enjoyment and 397 for sense of place). We found that the three ecosystem services analysed were spatially correlated, with similar hotspots appearing across the region. Most of the identified hotspots were located in the northern part of the region, which is characterised by mountains and forests. Other hotspots appeared within the city of Madrid, highlighting the importance of urban green areas. Natural protected areas supplied significantly more cultural ecosystem services than non-protected areas. Among CORINE land-use types, forested areas, mountain shrubs and rocky landscapes were more relevant than arable lands for the supply of cultural ecosystem services. Our results highlight the utmost importance of including ecosystem services mapping within land-use planning and policy-making agendas to ensure the conservation of areas supplying cultural services that are critical for societal wellbeing.
Silicate-, Magnesium Ion-, and Urea-Induced Prebiotic Phosphorylation of Uridine via Pyrophosphate; Revisiting the Hot Drying Water Pool Scenario
Authors: Gull Maheen , Omran Arthur , Feng Tian , Pasek Matthew A.
Published: July 2020

The availability of nucleotides on the early Earth is of great significance for the origin of a self-replicating system capable of undergoing evolution. We hereby report the successful phosphorylation reactions of the nucleoside uridine under heating in the “drying pool” prebiotic model at temperatures ranging from 60–75 °C, and by using pyrophosphate as a phosphorylation agent. Uridine monophosphates (UMP) such as uridine-5′-monophosphate (5′-UMP), 2′-UMP, and 3′-UMP, as well as cyclic 2′-3′-UMP, were identified by 31P-NMR. In addition to the above-mentioned products, a dimer of uridine-phosphate-uridine (U-P-U) was also observed. The reactions were promoted by white quartz sand, Mg2+, and by using urea as a condensation agent. The reactions also proceeded without this mixture; however, the yields increased remarkably with the presence of the above-mentioned materials. The results suggest that a hot/evaporating-drying pool of water containing organics, salts, and reactive phosphorus could be sufficient to form significant phosphate esters.
The Conformational Plasticity Vista of PDZ Domains
Authors: Murciano-Calles Javier
Published: July 2020

The PDZ domain (PSD95-Discs large-ZO1) is a widespread modular domain present in the living organisms. A prevalent function in the PDZ family is to serve as scaffolding and adaptor proteins connecting multiple partners in signaling pathways. An explanation of the flexible functionality in this domain family, based just on a static perspective of the structure–activity relationship, might fall short. More dynamic and conformational aspects in the protein fold can be the reasons for such functionality. Folding studies indeed showed an ample and malleable folding landscape for PDZ domains where multiple intermediate states were experimentally detected. Allosteric phenomena that resemble energetic coupling between residues have also been found in PDZ domains. Additionally, several PDZ domains are modulated by post-translational modifications, which introduce conformational switches that affect binding. Altogether, the ability to connect diverse partners might arise from the intrinsic plasticity of the PDZ fold.
Mapping of Photochemically-Derived Dityrosine across Fe-Bound N-Acetylated α-Synuclein
Authors: Curry Alyson M. , Fernàndez Ricardo D. , Pagani Talita D. , Abeyawardhane Dinendra L. , Trahan Morgan L. , Lucas Heather R.
Published: July 2020

Parkinson’s disease (PD) is the second most common neurological disease and belongs to a group of neurodegenerative disorders called synucleinopathies in which pathological aggregates of N-terminally acetylated α-synuclein (NAcα-Syn) accumulate in various regions of the brain. In PD, these NAcα-Syn aggregates have been found to contain covalent dityrosine crosslinks, which can occur either intermolecularly or intramolecularly. Cerebral metal imbalance is also a hallmark of PD, warranting investigations into the effects of brain biometals on NAcα-Syn. NAcα-Syn is an intrinsically disordered protein, and metal-mediated conformational modifications of this structurally dynamic protein have been demonstrated to influence its propensity for dityrosine formation. In this study, a library of tyrosine-to-phenylalanine (Y-to-F) NAcα-Syn constructs were designed in order to elucidate the nature and the precise residues involved in dityrosine crosslinking of Fe-bound NAcα-Syn. The structural capacity of each mutant to form dityrosine crosslinks was assessed using Photo-Induced Cross-Linking of Unmodified Proteins (PICUP), demonstrating that coordination of either FeIII or FeII to NAcα-Syn inhibits dityrosine crosslinking among the C-terminal residues. We further demonstrate that Y39 is the main contributor to dityrosine formation of Fe-bound NAcα-Syn, while Y125 is the main residue involved in dityrosine crosslinks in unmetalated NAcα-Syn. Our results confirm that iron coordination has a global effect on NAcα-Syn structure and reactivity.
Effect of Porosity on Functional Properties of Lead-Free Piezoelectric BaZr0.15Ti0.85O3 Porous Ceramics
Authors: Curecheriu Lavinia , Lukacs Vlad Alexandru , Padurariu Leontin , Stoian George , Ciomaga Cristina Elena
Published: July 2020

The present paper reports the dependence of dielectric, ferroelectric and piezoelectric properties on the porosity level in BaZr0.15Ti0.85O3 ceramics with porosity from 5% to 21%. Microporosity with 0–3 connectivity has been produced using PMMA microspheres as a sacrificial template. The functional properties (dielectric, ferroelectric and piezoelectric effect) are mostly affected by the “dilution effect”: permittivity decreases by 40% when porosity increases by 21%, and Pmax decreases from 13 to 5 µC/cm2 while the Prem is in the range of (2–8) µC/cm2. However, the reduction of the zero-field permittivity and hysteretic behaviour of ε(E) while the tunability level is still high makes from porous ceramics interesting materials for tunability application.
Additively Manufactured Al/SiC Cylindrical Structures by Laser Metal Deposition
Authors: Riquelme Ainhoa , Rodrigo Pilar , Escalera-Rodríguez María Dolores , Rams Joaquín
Published: July 2020

Preliminary characterization of the microstructure of Al/SiCp composites prepared by Laser Metal Deposition (LMD) was analyzed, and the microhardness and wear behavior of the materials manufactured have been evaluated. It has been determined that the combined effect of the laser speed and power is decisive for the fabrication process. The microstructure characterization shows that the presence of hygroscopic Al4C3 can be avoided by adding Ti to the composite matrix. The wear behavior of the LMD samples and their microhardness have been compared with Powder Metallurgy samples with the same composition. The LMD samples showed higher hardness and wear resistance.
Cotton Terry Textiles with Photo- and Bio-Activity in a Model Study and Real Conditions
Authors: Gutarowska Beata , Szulc Justyna , Matyjas-Zgondek Edyta , Kulpiński Piotr , Pielech-Przybylska Katarzyna , Rygała Anna , Jachowicz Anita , Rutkowski Eugeniusz
Published: July 2020

The aim of the study was to assess the photocatalytic (decompose staining particles, K/S values, the color differences, CIE L*a*b* color) and antimicrobial properties of textiles modified with TiO2 and ZnO nanoparticles (NPs) confirmed by X-ray diffraction, dynamic light scattering, SEM-EDX) in visible light conditions. The antimicrobial effectiveness of modified textiles under model conditions has been reported against 5 microorganisms: Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Candida albicans, Aspergillus niger (AATCC Test Method 100-2004). In real conditions in bathrooms, significant biostatic activity was shown on the surface of the modified towels. The number of microorganisms decreased by 1–5 log to the level of 0–5 CFU/cm2 in the case of bacteria: Enterobacteriaceae, Enterococcus, the coli group and E. coli, Pseudomonas. Statistically significant reduction of the total number of bacteria and fungi (by 1 log), and the concentration of gases (NO2, CO2, CO) in the air of bathrooms was determined. The removal or reduction of volatile organic compounds (VOCs) concentration (SPME-GC-MS analysis) in the air above the modified towels has also been determined. It was found that the lighting type (natural, artificial), time (1.5 and 7 h/day), air humidity (RH = 36–67%) and light intensity (81–167 lux) are important for the efficiency of photocatalysis. Textile materials modified with TiO2 and ZnO NPs can be used as self-cleaning towels. They can also help purify air from microorganisms, VOCs and undesirable gases.
Some Properties of Extended Euler’s Function and Extended Dedekind’s Function
Authors: Minculete Nicuşor , Savin Diana
Published: July 2020

In this paper, we find some properties of Euler’s function and Dedekind’s function. We also generalize these results, from an algebraic point of view, for extended Euler’s function and extended Dedekind’s function, in algebraic number fields. Additionally, some known inequalities involving Euler’s function and Dedekind’s function, we generalize them for extended Euler’s function and extended Dedekind’s function, working in a ring of integers of algebraic number fields.
Using an Adaptive Fuzzy Neural Network Based on a Multi-Strategy-Based Artificial Bee Colony for Mobile Robot Control
Authors: Chen Cheng-Hung , Jeng Shiou-Yun , Lin Cheng-Jian
Published: July 2020

This study proposes an adaptive fuzzy neural network (AFNN) based on a multi-strategy artificial bee colony (MSABC) algorithm for achieving an actual mobile robot navigation control. During the navigation control process, the AFNN inputs are the distance between the ultrasonic sensors and the angle between the mobile robot and the target, and the AFNN outputs are the robot’s left- and right-wheel speeds. A fitness function in reinforcement learning is defined to evaluate the navigation control performance of AFNN. The proposed MSABC algorithm improves the poor exploitation disadvantage in the traditional artificial bee colony (ABC) and adopts the mutation strategies of a differential evolution to balance exploration and exploitation. To escape in special environments, a manual wall-following fuzzy logic controller (WF-FLC) is designed. The experimental results show that the proposed MSABC method has improved the performance of average fitness, navigation time, and travel distance by 79.75%, 33.03%, and 10.74%, respectively, compared with the traditional ABC method. To prove the feasibility of the proposed controller, experiments were carried out on the actual PIONEER 3-DX mobile robot, and the proposed navigation control method was successfully completed.
Improving the Representativeness of a Simple Random Sample: An Optimization Model and Its Application to the Continuous Sample of Working Lives
Authors: Núñez-Antón Vicente , Pérez-Salamero González Juan Manuel , Regúlez-Castillo Marta , Vidal-Meliá Carlos
Published: July 2020

This paper proposes an optimization model for selecting a larger subsample that improves the representativeness of a simple random sample previously obtained from a population larger than the population of interest. The problem formulation involves convex mixed-integer nonlinear programming (convex MINLP) and is, therefore, NP-hard. However, the solution is found by maximizing the size of the subsample taken from a stratified random sample with proportional allocation and restricting it to a p-value large enough to achieve a good fit to the population of interest using Pearson’s chi-square goodness-of-fit test. The paper also applies the model to the Continuous Sample of Working Lives (CSWL), which is a set of anonymized microdata containing information on individuals from Spanish Social Security records and the results prove that it is possible to obtain a larger subsample from the CSWL that (far) better represents the pensioner population for each of the waves analyzed.
Mathematical Modeling of Vortex Interaction Using a Three-Layer Quasigeostrophic Model. Part 1: Point-Vortex Approach
Authors: Sokolovskiy Mikhail A. , Carton Xavier J. , Filyushkin Boris N.
Published: July 2020

The theory of point vortices is used to explain the interaction of a surface vortex with subsurface vortices in the framework of a three-layer quasigeostrophic model. Theory and numerical experiments are used to calculate the interaction between one surface and one subsurface vortex. Then, the configuration with one surface vortex and two subsurface vortices of equal and opposite vorticities (a subsurface vortex dipole) is considered. Numerical experiments show that the self-propelling dipole can either be captured by the surface vortex, move in its vicinity, or finally be completely ejected on an unbounded trajectory. Asymmetric dipoles make loop-like motions and remain in the vicinity of the surface vortex. This model can help interpret the motions of Lagrangian floats at various depths in the ocean.
The Effects of Variable Thermal Conductivity in Semiconductor Materials Photogenerated by a Focused Thermal Shock
Authors: Alzahrani Faris
Published: July 2020

In this work, the generalized photo-thermo-elastic model with variable thermal conductivity is presented to estimates the variations of temperature, the carrier density, the stress and the displacement in a semiconductor material. The effects of variable thermal conductivity under photo-thermal transport process is investigated by using the coupled model of thermoelastic and plasma wave. The surface of medium is loaded by uniform unit step temperature. Easily, the analytical solutions in the domain of Laplace are obtained. By using Laplace transforms with the eigenvalue scheme, the fields studied are obtained analytically and presented graphically.
The Loss-Averse Newsvendor Problem with Random Yield and Reference Dependence
Authors: Liu Wei , Song Shiji , Qiao Ying , Zhao Han , Wang Huachang
Published: July 2020

This paper studies a loss-averse newsvendor problem with reference dependence, where both demand and yield rate are stochastic. We obtain the loss-averse newsvendor’s optimal ordering policy and analyze the effects of loss aversion, reference dependence, random demand and yield on it. It is shown that the loss-averse newsvendor’s optimal order quantity and expected utility decreases in loss aversion level and reference point. Then, that this order quantity may be larger than the risk-neutral one’s if the reference point is less than a negative threshold. In addition, although the effect of random yield leads to an increase in the order quantity, the loss-averse newsvendor may order more than, equal to or less than the classical one, which significantly depends on loss aversion level and reference point. Numerical experiments were conducted to demonstrate our theoretical results.
Measure-Expansive Homoclinic Classes for C1 Generic Flows
Authors: Lee Manseob
Published: July 2020

In this paper, we prove that for a generically C1 vector field X of a compact smooth manifold M, if a homoclinic class H(γ,X) which contains a hyperbolic closed orbit γ is measure expansive for X then H(γ,X) is hyperbolic.
Dimension Reduction of Machine Learning-Based Forecasting Models Employing Principal Component Analysis
Authors: Meng Yinghui , Qasem Sultan Noman , Shokri Manouchehr , S Shahab
Published: July 2020

In this research, an attempt was made to reduce the dimension of wavelet-ANFIS/ANN (artificial neural network/adaptive neuro-fuzzy inference system) models toward reliable forecasts as well as to decrease computational cost. In this regard, the principal component analysis was performed on the input time series decomposed by a discrete wavelet transform to feed the ANN/ANFIS models. The models were applied for dissolved oxygen (DO) forecasting in rivers which is an important variable affecting aquatic life and water quality. The current values of DO, water surface temperature, salinity, and turbidity have been considered as the input variable to forecast DO in a three-time step further. The results of the study revealed that PCA can be employed as a powerful tool for dimension reduction of input variables and also to detect inter-correlation of input variables. Results of the PCA-wavelet-ANN models are compared with those obtained from wavelet-ANN models while the earlier one has the advantage of less computational time than the later models. Dealing with ANFIS models, PCA is more beneficial to avoid wavelet-ANFIS models creating too many rules which deteriorate the efficiency of the ANFIS models. Moreover, manipulating the wavelet-ANFIS models utilizing PCA leads to a significant decreasing in computational time. Finally, it was found that the PCA-wavelet-ANN/ANFIS models can provide reliable forecasts of dissolved oxygen as an important water quality indicator in rivers.
Partial Eigenvalue Assignment for Gyroscopic Second-Order Systems with Time Delay
Authors: Liu Hao , Li Ranran , Ding Yingying
Published: July 2020

In this paper, the partial eigenvalue assignment problem of gyroscopic second-order systems with time delay is considered. We propose a multi-step method for solving this problem in which the undesired eigenvalues are moved to desired values and the remaining eigenvalues are required to remain unchanged. Using the matrix vectorization and Hadamard product, we transform this problem into a linear systems of lower order, and analysis the computational costs of our method. Numerical results exhibit the efficiency of our method.
Emerging Technologies for the Extraction of Marine Phenolics: Opportunities and Challenges
Authors: Getachew Adane Tilahun , Jacobsen Charlotte , Holdt Susan Løvstad
Published: July 2020

Natural phenolic compounds are important classes of plant, microorganism, and algal secondary metabolites. They have well-documented beneficial biological activities. The marine environment is less explored than other environments but have huge potential for the discovery of new unique compounds with potential applications in, e.g., food, cosmetics, and pharmaceutical industries. To survive in a very harsh and challenging environment, marine organisms like several seaweed (macroalgae) species produce and accumulate several secondary metabolites, including marine phenolics in the cells. Traditionally, these compounds were extracted from their sample matrix using organic solvents. This conventional extraction method had several drawbacks such as a long extraction time, low extraction yield, co-extraction of other compounds, and usage of a huge volume of one or more organic solvents, which consequently results in environmental pollution. To mitigate these drawbacks, newly emerging technologies, such as enzyme-assisted extraction (EAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), pressurized liquid extraction (PLE), and supercritical fluid extraction (SFE) have received huge interest from researchers around the world. Therefore, in this review, the most recent and emerging technologies are discussed for the extraction of marine phenolic compounds of interest for their antioxidant and other bioactivity in, e.g., cosmetic and food industry. Moreover, the opportunities and the bottleneck for upscaling of these technologies are also presented.
Advances in the Study of Marine Products with Lipid-Lowering Properties
Authors: Zhao Jiarui , Cao Qi , Xing Maochen , Xiao Han , Cheng Zeyu , Song Shuliang , Ji Aiguo
Published: July 2020

With twice the number of cancer’s deaths, cardiovascular diseases have become the leading cause of death worldwide. Atherosclerosis, in particular, is a progressive, chronic inflammatory cardiovascular disease caused by persistent damage to blood vessels due to elevated cholesterol levels and hyperlipidemia. This condition is characterized by an increase in serum cholesterol, triglycerides, and low-density lipoprotein, and a decrease in high-density lipoprotein. Although existing therapies with hypolipidemic effects can improve the living standards of patients with cardiovascular diseases, the drugs currently used in clinical practice have certain side effects, which insists on the need for the development of new types of drugs with lipid-lowering effects. Some marine-derived substances have proven hypolipidemic activities with fewer side effects and stand as a good alternative for drug development. Recently, there have been thousands of studies on substances with lipid-lowering properties of marine origin, and some are already implemented in clinical practice. Here, we summarize the active components of marine-derived products having a hypolipidemic effect. These active constituents according to their source are divided into algal, animal, plant and microbial and contribute to the development and utilization of marine medicinal products with hypolipidemic effects.
Protein Recovery from Underutilised Marine Bioresources for Product Development with Nutraceutical and Pharmaceutical Bioactivities
Authors: Nguyen Trung T. , Heimann Kirsten , Zhang Wei
Published: July 2020

The global demand for dietary proteins and protein-derived products are projected to dramatically increase which cannot be met using traditional protein sources. Seafood processing by-products (SPBs) and microalgae are promising resources that can fill the demand gap for proteins and protein derivatives. Globally, 32 million tonnes of SPBs are estimated to be produced annually which represents an inexpensive resource for protein recovery while technical advantages in microalgal biomass production would yield secure protein supplies with minimal competition for arable land and freshwater resources. Moreover, these biomaterials are a rich source of proteins with high nutritional quality while protein hydrolysates and biopeptides derived from these marine proteins possess several useful bioactivities for commercial applications in multiple industries. Efficient utilisation of these marine biomaterials for protein recovery would not only supplement global demand and save natural bioresources but would also successfully address the financial and environmental burdens of biowaste, paving the way for greener production and a circular economy. This comprehensive review analyses the potential of using SPBs and microalgae for protein recovery and production critically assessing the feasibility of current and emerging technologies used for the process development. Nutritional quality, functionalities, and bioactivities of the extracted proteins and derived products together with their potential applications for commercial product development are also systematically summarised and discussed.
Mycorrhizal Fungi Isolated from Native Terrestrial Orchids from Region of La Araucanía, Southern Chile
Authors: Herrera Hector , Sanhueza Tedy , Martiarena Rodolfo , Valadares Rafael , Fuentes Alejandra , Arriagada Cesar
Published: July 2020

Mycorrhizal interactions of orchids are influenced by several environmental conditions. Hence, knowledge of mycorrhizal fungi associated with orchids inhabiting different ecosystems is essential to designing recovery strategies for threatened species. This study analyzes the mycorrhizal associations of terrestrial orchids colonizing grassland and understory in native ecosystems of the region of La Araucanía in southern Chile. Mycorrhizal fungi were isolated from peloton-containing roots and identified based on the sequence of the ITS region. Their capacities for seed germination were also investigated. We detected Tulasnella spp. and Ceratobasidium spp. in the pelotons of the analyzed orchids. Additionally, we showed that some Ceratobasidium isolates effectively induce seed germination to differing degrees, unlike Tulasnella spp., which, in most cases, fail to achieve protocorm growth. This process may underline a critical step in the life cycle of Tulasnella-associated orchids, whereas the Ceratobasidium-associated orchids were less specific for fungi and were effectively germinated with mycorrhizal fungi isolated from adult roots.
Fecal Pollution Drives Antibiotic Resistance and Class 1 Integron Abundance in Aquatic Environments of the Bolivian Andes Impacted by Mining and Wastewater
Authors: Agramont Jorge , Gutiérrez-Cortez Sergio , Joffré Enrique , Sjöling Åsa , Calderon Toledo Carla
Published: July 2020

An increased abundance of antibiotic resistance genes (ARGs) in aquatic environments has been linked to environmental pollution. Mining polluted sites with high concentration of metals could favor the in situ coselection of ARGs, whereas wastewater discharges release fecal antibiotic resistant bacteria in the environment. To study the effect of human fecal contamination and mining pollution, water and sediment samples affected by mining activities and sewage discharges were collected from three lakes in Bolivia, the pristine Andean lake Pata Khota, the Milluni Chico lake directly impacted by acid mine drainage, and the Uru-Uru lake located close to Oruro city and highly polluted by mining activities and human wastewater discharges. Physicochemical parameters, including metal composition, were analyzed in water and sediment samples. ARGs were screened for and verified by quantitative polymerase chain reaction (PCR) together with the mobile element class 1 integron (intl1), as well as crAssphage, a marker of human fecal pollution. The gene intl1 was positively correlated with sul1, sul2, tetA, and blaOXA-2. CrAssphage was only detected in the Uru-Uru lake, and its tributaries and significantly higher abundance of ARGs were found in these sites. Multivariate analysis showed that crAssphage abundance, electrical conductivity, and pH were positively correlated with higher levels of intl1 and ARGs. Taken together, our results suggest that fecal pollution is the major driver of higher levels of ARGs and intl1 in environments contaminated by wastewater and mining activities.
What Drives the Diversity of the Most Abundant Terrestrial Cercozoan Family (Rhogostomidae, Cercozoa, Rhizaria)?
Authors: Öztoprak Hüsna , Walden Susanne , Heger Thierry , Bonkowski Michael , Dumack Kenneth
Published: July 2020

Environmental sequencing surveys of soils and freshwaters revealed high abundance and diversity of the Rhogostomidae, a group of omnivorous thecate amoebae. This is puzzling since only a few Rhogostomidae species have yet been described and only a handful of reports mention them in field surveys. We investigated the putative cryptic diversity of the Rhogostomidae by a critical re-evaluation of published environmental sequencing data and in-depth ecological and morphological trait analyses. The Rhogostomidae exhibit an amazing diversity of genetically distinct clades that occur in a variety of different environments. We further broadly sampled for Rhogostomidae species; based on these isolates, we describe eleven new species and highlight important morphological traits for species delimitation. The most important environmental drivers that shape the Rhogostomidae community were soil moisture, soil pH, and total plant biomass. The length/width ratio of the theca was a morphological trait related to the colonized habitats, but not the shape and size of the aperture that is often linked to moisture adaption in testate and thecate amoebae.
SARS-CoV-2 RNA Persistence in Naso-Pharyngeal Swabs
Authors: Danzetta Maria Luisa , Amato Laura , Cito Francesca , Di Giuseppe Alessandra , Morelli Daniela , Savini Giovanni , Mercante Maria Teresa , Lorusso Alessio , Portanti Ottavio , Puglia Ilaria , Monaco Federica , Casaccia Claudia , Di Gennaro Annapia , Testa Lilia , Migliorati Giacomo , D’Alterio Nicola , Calistri Paolo
Published: July 2020

Since February 2020, Italy has been seriously affected by the SARS-CoV-2 pandemic. To support the National Health Care system, naso-pharyngeal/oropharyngeal swabs collected from suspected cases of Teramo province, Abruzzo region, are tested at Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise G. Caporale, for the presence of SARS-CoV-2 RNA. Out of 12,446 tested individuals, 605 returned positive results at least once, with prevalence significantly higher in men. A reduction of the level of viral RNA in the first swab per each positive patient collected over time was also observed. Moreover, 81 patients had at least one positive sample and two final negative tests: positivity in swabs lasted from 14 to 63 days, with a median value of 30 days. This shows the potential for the virus to coexist with patients for a long time, although we highlighted intermittent positivity in several cases. The evolution of the SARS-CoV-2 epidemiological situation and knowledge on viral shedding should be closely monitored, to interpret the findings correctly and adjust accordingly the surveillance activities.
High Prevalence of Human Polyomavirus 7 in Cholangiocarcinomas and Adjacent Peritumoral Hepatocytes: Preliminary Findings
Authors: Klufah Faisal , Mobaraki Ghalib , Chteinberg Emil , Alharbi Raed A. , Winnepenninckx Véronique , Speel Ernst Jan M. , Rennspiess Dorit , Olde Damink Steven W. , Neumann Ulf P. , Kurz Anna Kordelia , Samarska Iryna , zur Hausen Axel
Published: July 2020

Cholangiocarcinoma (CCA) is a rare biliary-duct malignancy with poor prognosis. Recently, the presence of the human polyomavirus 6 (HPyV6) has been reported in the bile of diverse hepatobiliary diseases, particularly in the bile of CCA patients. Here, we investigated the presence of novel HPyVs in CCA tissues using diverse molecular techniques to assess a possible role of HPyVs in CCA. Formalin-Fixed Paraffin-Embedded (FFPE) tissues of 42 CCA patients were included in this study. PCR-based screening for HPyVs was conducted using degenerated and HPyV-specific primers. Following that, we performed FISH, RNA in situ hybridization (RNA-ISH), and immunohistochemistry (IHC) to assess the presence of HPyVs in selected tissues. Of all 42 CCAs, 25 (59%) were positive for one HPyV, while 10 (24%) CCAs were positive for 2 HPyVs simultaneously, and 7 (17%) were negative for HPyVs. Of the total 35 positive CCAs, 19 (45%) were positive for HPyV7, 4 (9%) for HPyV6, 2 (5%) for Merkel cell polyomavirus (MCPyV), 8 (19%) for both HPyV7/MCPyV, and 2 (5%) for both HPyV6/HPyV7 as confirmed by sequencing. The presence of viral nucleic acids was confirmed by specific FISH, while the RNA-ISH confirmed the presence of HPyV6 on the single-cell level. In addition, expression of HPyV7, HPyV6, and MCPyV proteins were confirmed by IHC. Our results strongly indicate that HPyV7, HPyV6, and MCPyV infect bile duct epithelium, hepatocytes, and CCA cells, which possibly suggest an indirect role of these viruses in the etiopathogenesis of CCA. Furthermore, the observed hepatotropism of these novel HPyV, in particular HPyV7, might implicate a role of these viruses in other hepatobiliary diseases.