bluuebunny/crossref_metadata_2025 huggingface dataset:
New Adaptive Control Strategy for a Wind Turbine Permanent Magnet Synchronous Generator (PMSG)
Authors: Cao Wenping , Xing Ning , Wen Yan , Chen Xiangping , Wang Dong
Published: December 2020

Wind energy conversion systems have become a key technology to harvest wind energy worldwide. In permanent magnet synchronous generator-based wind turbine systems, the rotor position is needed for variable speed control and it uses an encoder or a speed sensor. However, these sensors lead to some obstacles, such as additional weight and cost, increased noise, complexity and reliability issues. For these reasons, the development of new sensorless control methods has become critically important for wind turbine generators. This paper aims to develop a new sensorless and adaptive control method for a surface-mounted permanent magnet synchronous generator. The proposed method includes a new model reference adaptive system, which is used to estimate the rotor position and speed as an observer. Adaptive control is implemented in the pulse-width modulated current source converter. In the conventional model reference adaptive system, the proportional-integral controller is used in the adaptation mechanism. Moreover, the proportional-integral controller is generally tuned by the trial and error method, which is tedious and inaccurate. In contrast, the proposed method is based on model predictive control which eliminates the use of speed and position sensors and also improves the performance of model reference adaptive control systems. In this paper, the proposed predictive controller is modelled in MATLAB/SIMULINK and validated experimentally on a 6-kW wind turbine generator. Test results prove the effectiveness of the control strategy in terms of energy efficiency and dynamical adaptation to the wind turbine operational conditions. The experimental results also show that the control method has good dynamic response to parameter variations and external disturbances. Therefore, the developed technique will help increase the uptake of permanent magnet synchronous generators and model predictive control methods in the wind power industry.
COVID-19 Pandemic and Upcoming Influenza Season—Does an Expert’s Computed Tomography Assessment Differentially Identify COVID-19, Influenza and Pneumonias of Other Origin?
Authors: Rueckel Johannes , Fink Nicola , Kaestle Sophia , Stüber Theresa , Schwarze Vincent , Gresser Eva , Hoppe Boj F. , Rudolph Jan , Kunz Wolfgang G. , Ricke Jens , Sabel Bastian O.
Published: December 2020

(1) Background: Time-consuming SARS-CoV-2 RT-PCR suffers from limited sensitivity in early infection stages whereas fast available chest CT can already raise COVID-19 suspicion. Nevertheless, radiologists’ performance to differentiate COVID-19, especially from influenza pneumonia, is not sufficiently characterized. (2) Methods: A total of 201 pneumonia CTs were identified and divided into subgroups based on RT-PCR: 78 COVID-19 CTs, 65 influenza CTs and 62 Non-COVID-19-Non-influenza (NCNI) CTs. Three radiology experts (blinded from RT-PCR results) raised pathogen-specific suspicion (separately for COVID-19, influenza, bacterial pneumonia and fungal pneumonia) according to the following reading scores: 0—not typical/1—possible/2—highly suspected. Diagnostic performances were calculated with RT-PCR as a reference standard. Dependencies of radiologists’ pathogen suspicion scores were characterized by Pearson’s Chi2 Test for Independence. (3) Results: Depending on whether the intermediate reading score 1 was considered as positive or negative, radiologists correctly classified 83–85% (vs. NCNI)/79–82% (vs. influenza) of COVID-19 cases (sensitivity up to 94%). Contrarily, radiologists correctly classified only 52–56% (vs. NCNI)/50–60% (vs. COVID-19) of influenza cases. The COVID-19 scoring was more specific than the influenza scoring compared with suspected bacterial or fungal infection. (4) Conclusions: High-accuracy COVID-19 detection by CT might expedite patient management even during the upcoming influenza season.
Cancer Signaling Transcriptome Is Upregulated in Type 2 Diabetes Mellitus
Authors: Almanza-Aguilera Enrique , Hernáez Álvaro , Corella Dolores , Sanllorente Albert , Ros Emilio , Portolés Olga , Valussi Julieta , Estruch Ramon , Coltell Oscar , Subirana Isaac , Canudas Silvia , Razquin Cristina , Blanchart Gemma , Nonell Lara , Fitó Montserrat , Castañer Olga
Published: December 2020

We aimed to explore the differences in the whole transcriptome of peripheral blood mononuclear cells between elderly individuals with and without type 2 diabetes (T2D). We conducted a microarray-based transcriptome analysis of 19 individuals with T2D and 15 without. Differentially expressed genes according to linear models were submitted to the Ingenuity Pathway Analysis system to conduct a functional enrichment analysis. We established that diseases, biological functions, and canonical signaling pathways were significantly associated with T2D patients when their logarithms of Benjamini–Hochberg-adjusted p-value were >1.30 and their absolute z-scores were >2.0 (≥2.0 meant “upregulation” and ≤ −2.0 “downregulation”). Cancer signaling pathways were the most upregulated ones in T2D (z-score = 2.63, −log(p-value) = 32.3; 88.5% (n = 906) of the total differentially expressed genes located in these pathways). In particular, integrin (z-score = 2.52, −log(p-value) = 2.03) and paxillin (z-score = 2.33, −log(p-value) = 1.46) signaling pathways were predicted to be upregulated, whereas the Rho guanosine diphosphate (Rho-GDP) dissociation inhibitor signaling pathway was predicted to be downregulated in T2D individuals (z-score = −2.14, −log(p-value) = 2.41). Our results suggest that, at transcriptional expression level, elderly individuals with T2D present an increased activation of signaling pathways related to neoplastic processes, T-cell activation and migration, and inflammation.
Pan-Genotype Pre-Exposure Prophylaxis (PrEP) Allows Transplantation of HCV-Positive Donor Kidneys to Negative Transplant Recipients
Authors: Duerr Michael , Liefeldt Lutz , Friedersdorff Frank , Choi Mira , Öllinger Robert , Hofmann Jörg , Budde Klemens , Schrezenmeier Eva , Halleck Fabian
Published: December 2020

Transplant candidates are facing incremental mortality risks on the waiting list. Here, we report a novel strategy to expand the donor pool by including hepatitis C seropositive (HCV+) donors. We investigated a pre-exposure prophylactic (PrEP) treatment with direct-acting antivirals (DAA) to allow transplantation for HCV seronegative (HCV−) kidney transplant recipients (KTR) with the aim to prevent HCV infection post transplantation. In this prospective trial, a pan-genotypic PrEP with daclatasvir and sofosbuvir once daily for 12 week was administered at transplantation. The primary endpoint sustained virological negativity (SVN) 12 weeks after the end of PrEP. Seven patients received a transplantation from four HCV+ donors. Accumulated waiting time was 70 ± 31.3 months already. Of note, study subjects underwent transplantation 24.7 ± 16.1 days after given consent. All KTR developed excellent graft function without any rejection episodes. One patient died with a functioning graft due to sepsis 13 months after transplantation. PrEP demonstrated efficacy with no signs of HCV transmission with excellent tolerability. Two out of four HCV+ donors were viremic at the time of explantation. Interestingly, KTR developed HCV antibodies also from non viramic donors. The acceptance of HCV+ donor was safe and reduced waiting time under the protection of PrEP DAA in kidney transplantation.
Is It Possible to Personalize the Diagnosis and Treatment of Breast Cancer during Pregnancy?
Authors: Tesarova Petra , Pavlista David , Parizek Antonin
Published: December 2020

The main goal of precision medicine in patients with breast cancer is to tailor the treatment according to the particular genetic makeup and the genetic changes in the cancer cells. Breast cancer occurring during pregnancy (BCP) is a complex and difficult clinical problem. Although it is not very common, both maternal and fetal outcome must be always considered when planning treatment. Pregnancy represents a significant barrier to the implementation of personalized treatment for breast cancer. Tailoring therapy mainly takes into account the stage of pregnancy, the subtype of cancer, the stage of cancer, and the patient’s preference. Results of the treatment of breast cancer in pregnancy are as yet not very satisfactory because of often delayed diagnosis, and it usually has an unfavorable outcome. Treatment of patients with pregnancy-associated breast cancer should be centralized. Centralization may result in increased experience in diagnosis and treatment and accumulated data may help us to optimize the treatment approaches, modify general treatment recommendations, and improve the survival and quality of life of the patients.
The Temple Grandin Genome: Comprehensive Analysis in a Scientist with High-Functioning Autism
Authors: Vanzo Rena , Prasad Aparna , Staunch Lauren , Hensel Charles , Serrano Moises , Wassman E. , Kaplun Alexander , Grandin Temple , Boles Richard
Published: December 2020

Autism spectrum disorder (ASD) is a heterogeneous condition with a complex genetic etiology. The objective of this study is to identify the complex genetic factors that underlie the ASD phenotype and other clinical features of Professor Temple Grandin, an animal scientist and woman with high-functioning ASD. Identifying the underlying genetic cause for ASD can impact medical management, personalize services and treatment, and uncover other medical risks that are associated with the genetic diagnosis. Prof. Grandin underwent chromosomal microarray analysis, whole exome sequencing, and whole genome sequencing, as well as a comprehensive clinical and family history intake. The raw data were analyzed in order to identify possible genotype-phenotype correlations. Genetic testing identified variants in three genes (SHANK2, ALX1, and RELN) that are candidate risk factors for ASD. We identified variants in MEFV and WNT10A, reported to be disease-associated in previous studies, which are likely to contribute to some of her additional clinical features. Moreover, candidate variants in genes encoding metabolic enzymes and transporters were identified, some of which suggest potential therapies. This case report describes the genomic findings in Prof. Grandin and it serves as an example to discuss state-of-the-art clinical diagnostics for individuals with ASD, as well as the medical, logistical, and economic hurdles that are involved in clinical genetic testing for an individual on the autism spectrum.
Urban Green Fabric Analysis Promoting Sustainable Planning in Guatemala City
Authors: Castillo-Cabrera Fernando , Wellmann Thilo , Haase Dagmar
Published: December 2020

Urbanization rate in Central America is the second fastest worldwide and its major cities face challenges regarding urban sustainability. Urban Green Fabric (UGF) is an important material condition for the urban quality of life and, therefore, key to planning processes. We performed an analysis of the UGF of Guatemala City including the identification and classification of UGF, their spatial pattern analysis, construction of ensembles of districts (zones) and revealing citizen’s interactions with UGF. We used remote sensing and land use mapping techniques, spatial metrics and a questionnaire survey. Main results are the UGF map of Guatemala City and six ensembles of zones based on a set of indicators. We further revealed citizens’ recognition of green spaces, their perceptions about green space amount and availability as well as their support for UGF future interventions. Finally, we discuss the implications for planning promoted by our results and suggest three actions for UGF sustainability: Creation of new green spaces, protecting existing green spaces and enhancing the mosaic with different green spaces types. UGF is an essential decision support tool for a diversity of actors.
Those Who “Don’t Move” Dynamics of Mobility at Two Crossing Points on the Guatemala-Mexico Borderland, from the Experience of Workers Who Vitalize the Region
Authors: Fernández-Casanueva Carmen
Published: December 2020

Drawing on qualitative research carried out in 2018 at two crossing points at the Guatemala-Mexico border, I focus my attention on individuals enabling movement and border crossing. These include money changers (cambistas or cambiadores), so-called tricyclists (tricilceros, people whose activity facilitates the transport of merchandise), motorcycle taxi drivers (locally called tuk tuks), rafters (balseros o camareros, in charge of the rafts that cross the border river), and, in general, people directly linked to movements in the region and across the border. Local actors like them, often overlooked, are the cogs that allow one side of the border to be connected to the other. Mobility and this specific space are affected by their imprint, their actions, and by the way they relate to their environment. Their aim is to be able to remain and protect their livelihood; in order to be able to not move, they allow movement across the border, shaping mobility, and also immobility, in the borderland. They are key actors in the construction of the border dynamic, mobility, and the space surrounding the line that divides both countries geopolitically. Although they play a role in the construction of (im)mobility of this space, they are subjects whose lives, destinies, and opportunities are intimately linked to the interactions and dynamics that take place there.
The Gradient Effect on the Relationship between the Underlying Factor and Land Surface Temperature in Large Urbanized Region
Authors: Wang Yixu , Xu Mingxue , Li Jun , Jiang Nan , Wang Dongchuan , Yao Lei , Xu Ying
Published: December 2020

Although research relating to the urban heat island (UHI) phenomenon has been significantly increasing in recent years, there is still a lack of a continuous and clear recognition of the potential gradient effect on the UHI—landscape relationship within large urbanized regions. In this study, we chose the Beijing-Tianjin-Hebei (BTH) region, which is a large scaled urban agglomeration in China, as the case study area. We examined the causal relationship between the LST variation and underlying surface characteristics using multi-temporal land cover and summer average land surface temperature (LST) data as the analyzed variables. This study then further discussed the modeling performance when quantifying their relationship from a spatial gradient perspective (the grid size ranged from 6 to 24 km), by comparing the ordinary least squares (OLS) and geographically weighted regression (GWR) methods. The results indicate that: (1) both the OLS and GWR analysis confirmed that the composition of built-up land contributes as an essential factor that is responsible for the UHI phenomenon in a large urban agglomeration region; (2) for the OLS, the modeled relationship between the LST and its drive factor showed a significant spatial gradient effect, changing with different spatial analysis grids; and, (3) in contrast, using the GWR model revealed a considerably robust and better performance for accommodating the spatial non-stationarity with a lower scale dependence than that of the OLS model. This study highlights the significant spatial heterogeneity that is related to the UHI effect in large-extent urban agglomeration areas, and it suggests that the potential gradient effect and uncertainty induced by different spatial scale and methodology usage should be considered when modeling the UHI effect with urbanization. This would supplement current UHI study and be beneficial for deepening the cognition and enlightenment of landscape planning for UHI regulation.
Hydrogels Based on Poly(Ether-Ester)s as Highly Controlled 5-Fluorouracil Delivery Systems—Synthesis and Characterization
Authors: Kasiński Adam , Zielińska-Pisklak Monika , Oledzka Ewa , Nałęcz-Jawecki Grzegorz , Drobniewska Agata , Sobczak Marcin
Published: December 2020

A novel and promising hydrogel drug delivery system (DDS) capable of releasing 5‑fluorouracil (5-FU) in a prolonged and controlled manner was obtained using ε‑caprolactone‑poly(ethylene glycol) (CL-PEG) or rac‑lactide-poly(ethylene glycol) (rac‑LA-PEG) copolymers. Copolymers were synthesized via the ring-opening polymerization (ROP) process of cyclic monomers, ε‑caprolactone (CL) or rac-lactide (rac-LA), in the presence of zirconium(IV) octoate (Zr(Oct)4) and poly(ethylene glycol) 200 (PEG 200) as catalyst and initiator, respectively. Obtained triblock copolymers were characterized by nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC) techniques; the structure and tacticity of the macromolecules were determined. The relationship between the copolymer structure and the reaction conditions was evaluated. The optimal conditions were specified as 140 °C and 24 h. In the next step, CL-PEG and rac-LA-PEG copolymers were chemically crosslinked using hexamethylene diisocyanate (HDI). Selected hydrogels were subjected to in vitro antitumor drug release studies, and the release data were analyzed using zero-order, first-order, and Korsmeyer-Peppas mathematical models. Controlled and prolonged (up to 432 h) 5-FU release profiles were observed for all examined hydrogels with first-order or zero-order kinetics. The drug release mechanism was generally denoted as non-Fickian transport.
Innovative Bioactive Ag-SiO2/TiO2 Coating on a NiTi Shape Memory Alloy: Structure and Mechanism of Its Formation
Authors: Dulski Mateusz , Balcerzak Jacek , Simka Wojciech , Dudek Karolina
Published: December 2020

In recent years, more and more emphasis has been placed on the development and functionalization of metallic substrates for medical applications to improve their properties and increase their applicability. Today, there are many different types of approaches and materials that are used for this purpose. Our idea was based on a combination of a chemically synthesized Ag-SiO2 nanocomposite and the electrophoretic deposition approach on a NiTi shape memory substrate. As a result, silver-silica coating was developed on a previously passivated alloy, which was then subjected to sintering at 700 °C for 2 h. The micrometer-sized coat-forming material was composed of large agglomerates consisting of silica and a thin film of submicron- and nano- spherical-shaped particles built of silver, carbon, and oxygen. Structurally, the coatings consisted of a combination of nanometer-sized silver-carbonate that was embedded in thin amorphous silica and siloxy network. The temperature impact had forced morphological and structural changes such as the consolidation of the coat-forming material, and the partial coalescence of the silver and silica particles. As a result, a new continuous complex ceramic coating was formed and was analyzed in more detail using the XPS, XRD, and Raman methods. According to the structural and chemical analyses, the deposited Ag-SiO2 nanocomposite material’s reorganization was due to its reaction with a passivated TiO2 layer, which formed an atypical glass-like composite that consisted of SiO2-TiO2 with silver particles that stabilized the network. Finally, the functionalization of the NiTi surface did not block the shape memory effect.
Influence of Atomic Doping on Thermal Stability of Ferrite Nanoparticles—Structural and Magnetic Studies
Authors: Klekotka Urszula , Satuła Dariusz , Spassov Simo , Kalska-Szostko Beata
Published: December 2020

In this paper, a series of experiments are reported where ferrite nanoparticles were synthesized with different substitution percentages (5, 10, 15, or 20%) of Fe2+ by Co2+, Mn2+, or Ni2+ ions. Afterwards, the prepared nanoparticles were thermally treated between 50 and 500 °C in air for 24 h in order to observe how doping influences the oxidation process induced by temperature elevation and access to O2. Nanoparticles were imaged before and after thermal treatment by transmission electron microscopy and were analyzed by X-ray diffraction, vibrating sample magnetometry, and Mössbauer spectroscopy. Presented studies reveal that the amount and kind of doped transition metals (of replaced Fe2+) strongly affect the oxidation process of ferrite nanoparticles, which can govern the application possibility. Each transition element suppresses the oxidation process in comparison to pure Fe-oxides, with the highest impact seen with Ni2+.
Durability of Hydrophobic/Icephobic Coatings in Protection of Lightweight Concrete with Waste Aggregate
Authors: Barnat-Hunek Danuta , Góra Jacek , Widomski Marcin
Published: December 2020

The aim of the research presented in this paper is to evaluate the feasibility of using hydrophobic agents based on organosilicon compounds for surface protection of lightweight concrete modified with waste polystyrene. The experimental part pertains to the physical and mechanical properties of polystyrene-modified lightweight concrete. The concrete samples were prepared with the following ingredients: CEM I 42.5 R cement, recycled polystyrene (0–2 mm), quartz sand (0–2 mm), coarse river aggregate (2–16 mm), and water. Silane and tetramethoxysilane were employed for surface hydrophobization. Concrete with 20% polystyrene exhibits high porosity (25.22%), which is related to an increase in absorptivity (14.75%) compared to the reference concrete. The hydrophobized concrete is characterized by the lowest surface free energy (SFE) value, which is 7 or 11 times lower than the value of reference concrete, depending on the agents. The test on the contact angle (CA) was performed before and after the frost-resistance test (F–T test). Lower SFE translates into lower adhesive properties, higher resistance of the material to the infiltration of water and corrosive compounds, e.g., salts, and higher resistance to freezing and thawing cycles. Silane and tetramethoxysilane coating raised frost resistance by 54–58% compared to the reference samples. This agent reduced absorptivity by 30%. Recycled polystyrene can be successfully used to produce lightweight concrete (LC) with high durability provided by hydrophobic/icephobic coatings.
Enhancement of 3D-Printable Materials by Dual-Curing Procedures
Authors: Fernández-Francos Xavier , Konuray Osman , Ramis Xavier , Serra Àngels , De la Flor Silvia
Published: December 2020

Dual-curing thermosetting systems are recently being developed as an alternative to conventional curing systems due to their processing flexibility and the possibility of enhancing the properties of cured parts in single- or multi-stage processing scenarios. Most dual-curing systems currently employed in three-dimensional (3D) printing technologies are aimed at improving the quality and properties of the printed parts. However, further benefit can be obtained from control in the curing sequence, making it possible to obtain partially reacted 3D-printed parts with tailored structure and properties, and to complete the reaction by activation of a second polymerization reaction in a subsequent processing stage. This paves the way for a range of novel applications based on the controlled reactivity and functionality of this intermediate material and the final consolidation of the 3D-printed part after this second processing stage. In this review, different strategies and the latest developments based on the concept of dual-curing are analyzed, with a focus on the enhanced functionality and emerging applications of the processed materials.
Critical Influence of the Processing Route on the Mechanical Properties of Zirconia Composites with Graphene Nanoplatelets
Authors: Gallardo-López Ángela , Muñoz-Ferreiro Carmen , López-Pernía Cristina , Jiménez-Piqué Emilio , Gutiérrez-Mora Felipe , Morales-Rodríguez Ana , Poyato Rosalía
Published: December 2020

Graphene-based nanostructures, used as potential reinforcement in ceramic composites, have a great tendency to agglomerate. This requires the use of homogenization techniques during the powder processing, posing the need to evaluate how these techniques affect the microstructure and the mechanical properties of the resulting composites. The influence of the processing route on the properties of 3YTZP (3 mol % yttria tetragonal zirconia polycrystals) ceramic composites with 10 vol % cost-effective GNP (graphene nanoplatelets) has been addressed. Four different powder processing routines combining ultrasonic powder agitation (UA) and planetary ball milling (PBM) in wet and dry media have been used and all the composites were densified by spark plasma sintering (SPS). The mechanical properties at room temperature in the macroscale have been assessed by Vickers indentations, four-point bending tests and the impulse-echo technique, while instrumented indentation was used to measure the hardness and Young’s modulus at the nanoscale. The application of dry-PBM enhances greatly the mechanical and electrical isotropy of the composites, slightly increases the hardness and lowers the elastic modulus, independently of the application of UA. The combination of UA and dry-PBM enhances the flexure strength by 50%, which is desirable for structural applications.
A Cytotoxic Porphyrin from North Pacific Brittle Star Ophiura sarsii
Authors: Klimenko Antonina , Huber Robin , Marcourt Laurence , Chardonnens Estelle , Koval Alexey , Khotimchenko Yuri S. , Ferreira Queiroz Emerson , Wolfender Jean-Luc , Katanaev Vladimir L.
Published: December 2020

Triple-negative breast cancer (TNBC) represents the deadliest form of gynecological tumors currently lacking targeted therapies. The ethanol extract of the North Pacific brittle star Ophiura sarsii presented promising anti-TNBC activities. After elimination of the inert material, the active extract was submitted to a bioguided isolation approach using high-resolution semipreparative HPLC-UV, resulting in one-step isolation of an unusual porphyrin derivative possessing strong cytotoxic activity. HRMS and 2D NMR resulted in the structure elucidation of the compound as (3S,4S)-14-Ethyl-9-(hydroxymethyl)-4,8,13,18-tetramethyl-20-oxo-3-phorbinepropanoic acid. Never identified before in Ophiuroidea, porphyrins have found broad applications as photosensitizers in the anticancer photodynamic therapy. The simple isolation of a cytotoxic porphyrin from an abundant brittle star species we describe here may pave the way for novel natural-based developments of targeted anti-cancer therapies.
Filtration of Elastic Polymers and Spherical Gels through a Silica-Deposited Layer on a Porous Membrane
Authors: Hidane Takanori , Kitani Hidemi , Morisada Shintaro , Ohto Keisuke , Kawakita Hidetaka , Furuta Sachiko
Published: December 2020

A 120-nm silica suspension was permeated through a porous polyethylene (PE) hollow-fiber membrane, as was a solution of deformable elastic particles of poly(N-isopropylacrylamide) (PNIPAM) gel and dextran. The amount adsorbed and flux of permeation were analyzed with ordinary differential equations to obtain adsorption coefficients, maximum amounts adsorbed, and pore-narrowing factors. The thickness of the “silica-deposited layer” on the membrane was 1 μm. In a batch adsorption mode, 5.0 mg of PNIPAM gel and 30 mg of dextran were adsorbed on the PE membrane, with no adsorption on the silica. The PE membrane pores were narrowed by a secondary layer of adsorbed PNIPAM gel. When filtered through the silica-deposited layer, PNIPAM gel occupies gaps, resulting in a reduced permeation flux. Dextran passed through the silica-deposited layer and was partially adsorbed on the PE membrane. The modified membrane can control adsorption, filtration, and flux permeation, which leads to dynamic membrane separations.
Build Strategy and Impact Strength of SLM Produced Maraging Steel (1.2709)
Authors: Jarfors Anders E. W. , Shashidhar Akash Chikke Gowda Hosapalya , Yepur Hrushi Kailash , Steggo Jacob , Andersson Nils-Eric , Stolt Roland
Published: December 2020

The current paper aimed to study the impact properties of additively manufactured maraging steel (1.2709) using laser powder bed fusion (PBF-L) processing. The specimens were fabricated using 3D Systems ProX 300 equipment under constant specific power input, or Andrew number. The interactions between the build strategy and parameters such as hatch spacing and scan speed was, and the impact strength and fracture were investigated. The impact energy anisotropy was also investigated in parallel and perpendicular to the build direction. Instrumented impact testing was performed, and the fractography supported that the fusion zone geometry dictated the fracture behavior. The influence from gaseous elements such as nitrogen, oxygen, and hydrogen was found insignificant at the levels found in the printed material.
Optimization of Manganese Recovery from a Solution Based on Lithium-Ion Batteries by Solvent Extraction with D2EHPA
Authors: Vieceli Nathália , Reinhardt Niclas , Ekberg Christian , Petranikova Martina
Published: December 2020

Manganese is a critical metal for the steelmaking industry, and it is expected that its world demand will be increasingly affected by the growing market of lithium-ion batteries. In addition to the increasing importance of manganese, its recycling is mainly determined by trends in the recycling of iron and steel. The recovery of manganese by solvent extraction has been widely investigated; however, the interaction of different variables affecting the process is generally not assessed. In this study, the solvent extraction of manganese from a solution based on lithium-ion batteries was modeled and optimized using factorial designs of experiments and the response surface methodology. Under optimized conditions (O:A of 1.25:1, pH 3.25, and 0.5 M bis(2-ethylhexyl) phosphoric acid (D2EHPA)), extractions above 70% Mn were reached in a single extraction stage with a coextraction of less than 5% Co, which was mostly removed in two scrubbing stages. A stripping product containing around 23 g/L Mn and around 0.3 g/L Co can be obtained under optimized conditions (O:A of 8:1, 1 M H2SO4 and around 13 min of contact time) in one stripping stage.
Heat Transfer Considerations on the Spontaneous Triggering of Vapor Explosions—A Review
Authors: Simons Arne , Bellemans Inge , Crivits Tijl , Verbeken Kim
Published: December 2020

Vapor explosions have been investigated both theoretically and experimentally for several decades, focusing either on the vapor film, or on mechanical aspects. Where the main interest for industry lies in the safety risks of such an event, fundamental research is focusing on all partial processes that occur during a vapor explosion. In this paper, vapor explosions are discussed from a heat transfer point of view. Generally accepted knowledge of heat transfer between hot surfaces and liquids is compared to early investigations regarding the origin of vapor explosions. Both steady state and transient models are discussed. The review of available literature suggests that vapor explosions trigger spontaneously by the collapse of the boiling film. Better understanding of the fundamental aspects of vapor explosions might give rise to future ideas on how to avoid them.
Metabolomic Analysis of Response to Nitrogen-Limiting Conditions in Yarrowia spp.
Authors: Dissook Sivamoke , Putri Sastia Prama , Fukusaki Eiichiro
Published: December 2020

Yarrowia is a yeast genus that has been used as a model oleaginous taxon for a wide array of studies. However, information regarding metabolite changes within Yarrowia spp. under different environmental conditions is still limited. Among various factors affecting Yarrowia metabolism, nitrogen-limiting conditions have a profound effect on the metabolic state of yeast. In this study, a time-course LC-MS/MS-based metabolome analysis of Y. lipolytica was performed to determine the optimal cultivation time and carbon-to-nitrogen ratio for studying the effects of nitrogen-limiting conditions on Yarrowia; we found that cultivation time of 36 h and carbon-to-nitrogen ratio of 4:1 and 5:0 was suitable for studying the effects of nitrogen-limiting conditions on Yarrowia and these conditions were applied to six strains of Yarrowia. These six strains of Yarrowia showed similar responses to nitrogen-limiting conditions; however, each strain had a unique metabolomic profile. Purine and pyrimidine metabolism were the most highly affected biological pathways in nitrogen-limiting conditions, indicating that these conditions affect energy availability within cells. This stress leads to a shift in cells to the utilization of a less ATP-dependent biological pathway. This information will be beneficial for the development of Yarrowia strains for further scientific and industrial applications.
Geochemical and Mineralogical Characterisation of Historic Zn–Pb Mine Waste, Plombières, East Belgium
Authors: Bevandić Srećko , Blannin Rosie , Vander Auwera Jacqueline , Delmelle Nicolas , Caterina David , Nguyen Frederic , Muchez Philippe
Published: December 2020

Mine wastes and tailings derived from historical processing may contain significant contents of valuable metals due to processing being less efficient in the past. The Plombières tailings pond in eastern Belgium was selected as a case study to determine mineralogical and geochemical characteristics of the different mine waste materials found at the site. Four types of material were classified: soil, metallurgical waste, brown tailings and yellow tailings. The distribution of the mine wastes was investigated with drill holes, pit-holes and geophysical methods. Samples of the materials were assessed with grain size analysis, and mineralogical and geochemical techniques. The mine wastes dominantly consist of SiO2, Al2O3 and Fe2O3. The cover material, comprising soil and metallurgical waste is highly heterogeneous in terms of mineralogy, geochemistry and grain size. The metallurgical waste has a high concentration of metals (Zn: 0.1 to 24 wt.% and Pb: 0.1 to 10.1 wt.%). In the tailings materials, Pb and Zn vary from 10 ppm to 8.5 wt.% and from 51 ppm to 4 wt.%, respectively. The mining wastes comprises mainly quartz, amorphous phases and phyllosilicates, with minor contents of Fe-oxide and Pb- and Zn-bearing minerals. Based on the mineralogical and geochemical properties, the different potential applications of the four waste material types were determined. Additionally, the theoretical economic potential of Pb and Zn in the mine wastes was estimated.
PEG-POSS Star Molecules Blended in Polyurethane with Flexible Hard Segments: Morphology and Dynamics
Authors: Raftopoulos Konstantinos N. , Hebda Edyta , Grzybowska Anna , Klonos Panagiotis A. , Kyritsis Apostolos , Pielichowski Krzysztof
Published: December 2020

A star polymer with a polyhedral oligomeric silsesquioxanne (POSS) core and poly(ethylene glycol) (PEG) vertex groups is incorporated in a polyurethane with flexible hard segments in-situ during the polymerization process. The blends are studied in terms of morphology, molecular dynamics, and charge mobility. The methods utilized for this purpose are scanning electron and atomic force microscopies (SEM, AFM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and to a larger extent dielectric relaxation spectroscopy (DRS). It is found that POSS reduces the degree of crystallinity of the hard segments. Contrary to what was observed in a similar system with POSS pendent along the main chain, soft phase calorimetric glass transition temperature drops as a result of plasticization, and homogenization of the soft phase by the star molecules. The dynamic glass transition though, remains practically unaffected, and a hypothesis is formed to resolve the discrepancy, based on the assumption of different thermal and dielectric responses of slow and fast modes of the system. A relaxation α′, slower than the bulky segmental α and common in polyurethanes, appears here too. A detailed analysis of dielectric spectra provides some evidence that this relaxation has cooperative character. An additional relaxation g, which is not commonly observed, accompanies the Maxwell Wagner Sillars interfacial polarization process, and has dynamics similar to it. POSS is found to introduce conductivity and possibly alter its mechanism. The study points out that different architectures of incorporation of POSS in polyurethane affect its physical properties by different mechanisms.
Alzheimer’s Disease: An Overview of Major Hypotheses and Therapeutic Options in Nanotechnology
Authors: Agarwal Mugdha , Alam Mohammad Rizwan , Haider Mohd Kabir , Malik Md. Zubbair , Kim Dae-Kwang
Published: December 2020

Alzheimer’s disease (AD), a progressively fatal neurodegenerative disorder, is the most prominent form of dementia found today. Patients suffering from Alzheimer’s begin to show the signs and symptoms, like decline in memory and cognition, long after the cellular damage has been initiated in their brain. There are several hypothesis for the neurodegeneration process; however, the lack of availability of in vivo models makes the recapitulation of AD in humans impossible. Moreover, the drugs currently available in the market serve to alleviate the symptoms and there is no cure for the disease. There have been two major hurdles in the process of finding the same—the inefficiency in cracking the complexity of the disease pathogenesis and the inefficiency in delivery of drugs targeted for AD. This review discusses the different drugs that have been designed over the recent years and the drug delivery options in the field of nanotechnology that have been found most feasible in surpassing the blood–brain barrier (BBB) and reaching the brain.
Reduction of Grain Boundary Resistance of La0.5Li0.5TiO3 by the Addition of Organic Polymers
Authors: Boyano Iker , Mainar Aroa R. , Blázquez J. Alberto , Kvasha Andriy , Bengoechea Miguel , de Meatza Iratxe , García-Martín Susana , Varez Alejandro , Sanz Jesus , García-Alvarado Flaviano
Published: December 2020

The organic solvents that are widely used as electrolytes in lithium ion batteries present safety challenges due to their volatile and flammable nature. The replacement of liquid organic electrolytes by non-volatile and intrinsically safe ceramic solid electrolytes is an effective approach to address the safety issue. However, the high total resistance (bulk and grain boundary) of such compounds, especially at low temperatures, makes those solid electrolyte systems unpractical for many applications where high power and low temperature performance are required. The addition of small quantities of a polymer is an efficient and low cost approach to reduce the grain boundary resistance of inorganic solid electrolytes. Therefore, in this work, we study the ionic conductivity of different composites based on non-sintered lithium lanthanum titanium oxide (La0.5Li0.5TiO3) as inorganic ceramic material and organic polymers with different characteristics, added in low percentage (<15 wt.%). The proposed cheap composite solid electrolytes double the ionic conductivity of the less cost-effective sintered La0.5Li0.5TiO3.
Uncovering the Magnetic Particle Imaging and Magnetic Resonance Imaging Features of Iron Oxide Nanocube Clusters
Authors: Avugadda Sahitya Kumar , Wickramasinghe Sameera , Niculaes Dina , Ju Minseon , Lak Aidin , Silvestri Niccolò , Nitti Simone , Roy Ipsita , Samia Anna Cristina S. , Pellegrino Teresa
Published: December 2020

Multifunctional imaging nanoprobes continue to garner strong interest for their great potential in the detection and monitoring of cancer. In this study, we investigate a series of spatially arranged iron oxide nanocube-based clusters (i.e., chain-like dimer/trimer, centrosymmetric clusters, and enzymatically cleavable two-dimensional clusters) as magnetic particle imaging and magnetic resonance imaging probes. Our findings demonstrate that the short nanocube chain assemblies exhibit remarkable magnetic particle imaging signal enhancement with respect to the individually dispersed or the centrosymmetric cluster analogues. This result can be attributed to the beneficial uniaxial magnetic dipolar coupling occurring in the chain-like nanocube assembly. Moreover, we could effectively synthesize enzymatically cleavable two-dimensional nanocube clusters, which upon exposure to a lytic enzyme, exhibit a progressive increase in magnetic particle imaging signal at well-defined incubation time points. The increase in magnetic particle imaging signal can be used to trace the disassembly of the large planar clusters into smaller nanocube chains by enzymatic polymer degradation. These studies demonstrate that chain-like assemblies of iron oxide nanocubes offer the best spatial arrangement to improve magnetic particle imaging signals. In addition, the nanocube clusters synthesized in this study also show remarkable transverse magnetic resonance imaging relaxation signals. These nanoprobes, previously showcased for their outstanding heat performance in magnetic hyperthermia applications, have great potential as dual imaging probes and could be employed to improve the tumor thermo-therapeutic efficacy, while offering a readable magnetic signal for image mapping of material disassemblies at tumor sites.
Long Non-Coding RNAs in Diffuse Large B-Cell Lymphoma
Authors: Karstensen Kasper Thystrup , Schein Aleks , Petri Andreas , Bøgsted Martin , Dybkær Karen , Uchida Shizuka , Kauppinen Sakari
Published: December 2020

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoid malignancy in adults. Although significant progress has been made in recent years to treat DLBCL patients, 30%–40% of the patients eventually relapse or are refractory to first line treatment, calling for better therapeutic strategies for DLBCL. Long non-coding RNAs (lncRNAs) have emerged as a highly diverse group of non-protein coding transcripts with intriguing molecular functions in human disease, including cancer. Here, we review the current understanding of lncRNAs in the pathogenesis and progression of DLBCL to provide an overview of the field. As the current knowledge of lncRNAs in DLBCL is still in its infancy, we provide molecular signatures of lncRNAs in DLBCL cell lines to assist further lncRNA research in DLBCL.
Biomedical Properties of Propolis on Diverse Chronic Diseases and Its Potential Applications and Health Benefits
Authors: Rivera-Yañez Nelly , Rivera-Yañez C. Rebeca , Pozo-Molina Glustein , Méndez-Catalá Claudia F. , Méndez-Cruz Adolfo R. , Nieto-Yañez Oscar
Published: December 2020

The use of alternative medicine products has increased tremendously in recent decades and it is estimated that approximately 80% of patients globally depend on them for some part of their primary health care. Propolis is a beekeeping product widely used in alternative medicine. It is a natural resinous product that bees collect from various plants and mix with beeswax and salivary enzymes and comprises a complex mixture of compounds. Various biomedical properties of propolis have been studied and reported in infectious and non-infectious diseases. However, the pharmacological activity and chemical composition of propolis is highly variable depending on its geographical origin, so it is important to describe and study the biomedical properties of propolis from different geographic regions. A number of chronic diseases, such as diabetes, obesity, and cancer, are the leading causes of global mortality, generating significant economic losses in many countries. In this review, we focus on compiling relevant information about propolis research related to diabetes, obesity, and cancer. The study of propolis could generate both new and accessible alternatives for the treatment of various diseases and will help to effectively evaluate the safety of its use.
Emotional Eating in Adolescence: Effects of Emotion Regulation, Weight Status and Negative Body Image
Authors: Shriver Lenka H. , Dollar Jessica M. , Calkins Susan D. , Keane Susan P. , Shanahan Lilly , Wideman Laurie
Published: December 2020

Emotional eating is associated with an increased risk of binge eating, eating in the absence of hunger and obesity risk. While previous studies with children and adolescents suggest that emotion regulation may be a key predictor of this dysregulated eating behavior, little is known about what other factors may be influencing the link between emotional regulation and emotional eating in adolescence. This multi-method longitudinal study (n = 138) utilized linear regression models to examine associations between childhood emotion regulation, adolescent weight status and negative body image, and emotional eating at age 17. Emotion regulation predicted adolescent emotional eating and this link was moderated by weight status (β = 1.19, p < 0.01) and negative body image (β = −0.34, p < 0.01). Higher engagement in emotional eating was predicted by lower emotional regulation scores among normal-weight teens (β = −0.46, p < 0.001) but not among overweight/obese teens (β = 0.32, p > 0.10). Higher scores on emotion regulation were significantly associated with lower emotional eating at high (β = −1.59, p < 0.001) and low (β = −1.00, p < 0.01) levels of negative body image. Engagement in emotional eating was predicted by higher negative body image among overweight/obese teens only (β = 0.70, p < 0.001). Our findings show that while better childhood emotion regulation skills are associated with lower emotional eating, weight status and negative body image influence this link and should be considered as important foci in future interventions that aim to reduce emotional eating in adolescence.
Balance between Retroviral Latency and Transcription: Based on HIV Model
Authors: Pluta Aneta , Jaworski Juan P. , Cortés-Rubio César N.
Published: December 2020

The representative of the Lentivirus genus is the human immunodeficiency virus type 1 (HIV-1), the causative agent of acquired immunodeficiency syndrome (AIDS). To date, there is no cure for AIDS because of the existence of the HIV-1 reservoir. HIV-1 infection can persist for decades despite effective antiretroviral therapy (ART), due to the persistence of infectious latent viruses in long-lived resting memory CD4+ T cells, macrophages, monocytes, microglial cells, and other cell types. However, the biology of HIV-1 latency remains incompletely understood. Retroviral long terminal repeat region (LTR) plays an indispensable role in controlling viral gene expression. Regulation of the transcription initiation plays a crucial role in establishing and maintaining a retrovirus latency. Whether and how retroviruses establish latency and reactivate remains unclear. In this article, we describe what is known about the regulation of LTR-driven transcription in HIV-1, that is, the cis-elements present in the LTR, the role of LTR transcription factor binding sites in LTR-driven transcription, the role of HIV-1-encoded transactivator protein, hormonal effects on virus transcription, impact of LTR variability on transcription, and epigenetic control of retrovirus LTR. Finally, we focus on a novel clustered regularly interspaced short palindromic repeats-associated protein 9 (CRISPR/dCas9)-based strategy for HIV-1 reservoir purging.