bluuebunny/crossref_metadata_2025 huggingface dataset:
Interleukin-17A Triggers the Release of Platelet-Derived Factors Driving Vascular Endothelial Cells toward a Pro-Angiogenic State
Authors: Gatsiou Aikaterini , Sopova Kateryna , Tselepis Alexandros , Stellos Konstantinos
Published: July 2021

Platelets comprise a highly interactive immune cell subset of the circulatory system traditionally known for their unique haemostatic properties. Although platelets are considered as a vault of growth factors, cytokines and chemokines with pivotal role in vascular regeneration and angiogenesis, the exact mechanisms by which they influence vascular endothelial cells (ECs) function remain underappreciated. In the present study, we examined the role of human IL-17A/IL-17RA axis in platelet-mediated pro-angiogenic responses. We reveal that IL-17A receptor (IL-17RA) mRNA is present in platelets transcriptome and a profound increase is documented on the surface of activated platelets. By quantifying the protein levels of several factors, involved in angiogenesis, we identified that IL-17A/IL17RA axis selectively induces the release of vascular endothelial growth factor, interleukin -2 and -4, as well as monocyte chemoattractant protein -1 from treated platelets. However, IL-17A exerted no effect on the release of IL-10, an anti-inflammatory factor with potentially anti-angiogenic properties, from platelets. Treatment of human endothelial cell two-dimensional tubule networks or three-dimensional spheroid and mouse aortic ring structures with IL-17A-induced platelet releasate evoked pro-angiogenic responses of ECs. Our findings suggest that IL-17A may critically affect platelet release of pro-angiogenic factors driving ECs towards a pro-angiogenic state.
The Energy Status of Astrocytes Is the Achilles’ Heel of eIF2B-Leukodystrophy
Authors: Herrero Melisa , Daw Maron , Atzmon Andrea , Elroy-Stein Orna
Published: July 2021

Translation initiation factor 2B (eIF2B) is a master regulator of global protein synthesis in all cell types. The mild genetic Eif2b5(R132H) mutation causes a slight reduction in eIF2B enzymatic activity which leads to abnormal composition of mitochondrial electron transfer chain complexes and impaired oxidative phosphorylation. Previous work using primary fibroblasts isolated from Eif2b5(R132H/R132H) mice revealed that owing to increased mitochondrial biogenesis they exhibit normal cellular ATP level. In contrast to fibroblasts, here we show that primary astrocytes isolated from Eif2b5(R132H/R132H) mice are unable to compensate for their metabolic impairment and exhibit chronic state of low ATP level regardless of extensive adaptation efforts. Mutant astrocytes are hypersensitive to oxidative stress and to further energy stress. Moreover, they show migration deficit upon exposure to glucose starvation. The mutation in Eif2b5 prompts reactive oxygen species (ROS)-mediated inferior ability to stimulate the AMP-activated protein kinase (AMPK) axis, due to a requirement to increase the mammalian target of rapamycin complex-1 (mTORC1) signalling in order to enable oxidative glycolysis and generation of specific subclass of ROS-regulating proteins, similar to cancer cells. The data disclose the robust impact of eIF2B on metabolic and redox homeostasis programs in astrocytes and point at their hyper-sensitivity to mutated eIF2B. Thereby, it illuminates the central involvement of astrocytes in Vanishing White Matter Disease (VWMD), a genetic neurodegenerative leukodystrophy caused by homozygous hypomorphic mutations in genes encoding any of the 5 subunits of eIF2B.
Critical Roles of Calpastatin in Ischemia/Reperfusion Injury in Aged Livers
Authors: Flores-Toro Joseph , Chun Sung-Kook , Shin Jun-Kyu , Campbell Joan , Lichtenberger Melissa , Chapman William , Zendejas Ivan , Behrns Kevin , Leeuwenburgh Christiaan , Kim Jae-Sung
Published: July 2021

Ischemia/reperfusion (I/R) injury unavoidably occurs during hepatic resection and transplantation. Aged livers poorly tolerate I/R during surgical treatment. Although livers have a powerful endogenous inhibitor of calpains, calpastatin (CAST), I/R activates calpains, leading to impaired autophagy, mitochondrial dysfunction, and hepatocyte death. It is unknown how I/R in aged livers affects CAST. Human and mouse liver biopsies at different ages were collected during in vivo I/R. Hepatocytes were isolated from 3-month- (young) and 26-month-old (aged) mice, and challenged with short in vitro simulated I/R. Cell death, protein expression, autophagy, and mitochondrial permeability transition (MPT) between the two age groups were compared. Adenoviral vector was used to overexpress CAST. Significant cell death was observed only in reperfused aged hepatocytes. Before the commencement of ischemia, CAST expression in aged human and mouse livers and mouse hepatocytes was markedly greater than that in young counterparts. However, reperfusion substantially decreased CAST in aged human and mouse livers. In hepatocytes, reperfusion rapidly depleted aged cells of CAST, cleaved autophagy-related protein 5 (ATG5), and induced defective autophagy and MPT onset, all of which were blocked by CAST overexpression. Furthermore, mitochondrial morphology was shifted toward an elongated shape with CAST overexpression. In conclusion, CAST in aged livers is intrinsically short-lived and lost after short I/R. CAST depletion contributes to age-dependent liver injury after I/R.
The Link between VAPB Loss of Function and Amyotrophic Lateral Sclerosis
Authors: Borgese Nica , Iacomino Nicola , Colombo Sara Francesca , Navone Francesca
Published: July 2021

The VAP proteins are integral adaptor proteins of the endoplasmic reticulum (ER) membrane that recruit a myriad of interacting partners to the ER surface. Through these interactions, the VAPs mediate a large number of processes, notably the generation of membrane contact sites between the ER and essentially all other cellular membranes. In 2004, it was discovered that a mutation (p.P56S) in the VAPB paralogue causes a rare form of dominantly inherited familial amyotrophic lateral sclerosis (ALS8). The mutant protein is aggregation-prone, non-functional and unstable, and its expression from a single allele appears to be insufficient to support toxic gain-of-function effects within motor neurons. Instead, loss-of-function of the single wild-type allele is required for pathological effects, and VAPB haploinsufficiency may be the main driver of the disease. In this article, we review the studies on the effects of VAPB deficit in cellular and animal models. Several basic cell physiological processes are affected by downregulation or complete depletion of VAPB, impinging on phosphoinositide homeostasis, Ca2+ signalling, ion transport, neurite extension, and ER stress. In the future, the distinction between the roles of the two VAP paralogues (A and B), as well as studies on motor neurons generated from induced pluripotent stem cells (iPSC) of ALS8 patients will further elucidate the pathogenic basis of p.P56S familial ALS, as well as of other more common forms of the disease.
Post Orgasmic Illness Syndrome (POIS) and Delayed Onset Muscle Soreness (DOMS): Do They Have Anything in Common?
Authors: Sonkodi Balázs , Kopa Zsolt , Nyirády Péter
Published: July 2021

Post orgasmic illness syndrome is a rare, mysterious condition with an unknown pathomechanism and uncertain treatment. The symptoms of post orgasmic illness syndrome last about 2–7 days after an ejaculation. The current hypothesis proposes that the primary injury in post orgasmic illness syndrome is an acute compression proprioceptive axonopathy in the muscle spindle, as is suspected in delayed onset muscle soreness. The terminal arbor degeneration-like lesion of delayed onset muscle soreness is theorized to be an acute stress response energy-depleted dysfunctional mitochondria-induced impairment of Piezo2 channels and glutamate vesicular release. The recurring symptoms of post orgasmic illness syndrome after each ejaculation are suggested to be analogous to the repeated bout effect of delayed onset muscle soreness. However, there are differences in the pathomechanism, mostly attributed to the extent of secondary tissue damage and to the extent of spermidine depletion. The spermidine depletion-induced differences are as follows: modulation of the acute stress response, flu-like symptoms, opioid-like withdrawal and enhanced deregulation of the autonomic nervous system. The longitudinal dimension of delayed onset muscle soreness, in the form of post orgasmic illness syndrome and the repeated bout effect, have cognitive and memory consequences, since the primary injury is learning and memory-related.
Modifying Precursor Solutions to Obtain Screen-Printable Inks for Tungsten Oxides Electrochromic Film Preparation
Authors: Guo Kaiyue , Zhang Guanguang , Long Yujie , Ning Honglong , Xu Zhuohui , Qiu Tian , Luo Dongxiang , Li Muyun , Yao Rihui , Peng Junbiao
Published: July 2021

Tungsten trioxide (WO3) is used to prepare the important electrochromic layer of the electrochromic device as a wide bandgap semiconductor material. In this study, WO3 electrochromic film was successfully prepared by screen printing. To modify the thixotropy and wettability of the ink, polyvinyl alcohol (PVA) and 2-perfluoroalkyl ethanol (FSO) were added in the ammonium meta-tungstate (AMT) solution. We found that the PVA additive could improve the dynamic viscosity of the solution and modify the uniformity of the film. 2-Perfluoroalkyl ethanol (FSO) could lower the surface tension and increase the wettability of the AMT solution on the substrate. By observing the morphology of the printed films, the ink formulas for screen printing were selected. We found the annealing process could help remove PVA. Through characterization of electrochromic performance, it was found that the best performing device had 42.57% modulation and 93.25 cm2·C−1 coloration efficiency (CE) for 600 nm light. This study showed great potential in the preparation of WO3 electrochromic devices by a low-cost screen-printing method.
Numerical Simulation and Parameter Analysis of Electromagnetic Riveting Process for Ti-6Al-4V Titanium Rivet
Authors: Qin Yangfan , Liao Yuxuan , Li Guangyao , Cui Junjia , Jiang Hao
Published: July 2021

Electromagnetic riveting process (EMR) is a high-speed impact connection technology with the advantages of fast loading speed, large impact force and stable rivet deformation. In this work, the axisymmetric sequential and loose electromagnetic-structural coupling simulation models were conducted to perform the electromagnetic riveting process of a Ti-6Al-4V titanium rivet, and the parameter analysis of the riveting setup was performed based on the sequential coupled simulation results. In addition, the single-objective optimization problem of punch displacement was conducted using the Hooke–Jeeves algorithm. Based on the adaptive remeshing technology adopted in air meshes, the deformation calculated in the structural field was well transferred to the electromagnetic field in the sequential coupled model. Thus, the sequential coupling simulation results presented higher accuracy on the punch speed and rivet deformation than the loose coupling numerical model. The maximum relative difference of electromagnetic force (EMF) on driver plate and radial displacement in the rivet shaft was 34.86% and 13.43%, respectively. The parameter analysis results showed that the outer diameter and the height of the driver plate had a significant first-order effect on the response of displacement, while the platform height, transition zone height, angle, and transition zone width of the amplifier presented a strong interaction effect. Using the obtained results on the optimal structural parameters, the punch speed was effectively improved from 6.13 to 8.12 m/s with a 32.46% increase. Furthermore, the displacement of the punch increasing from 3.38 to 3.81 mm would lead to an 80.55% increase in the maximum radial displacement of the rivet shaft. This indicated that the deformation of the rivet was efficiently improved by using the optimal rivet model.
Wear Behavior Analysis of Al2O3 Coatings Manufactured by APS and HVOF Spraying Processes Using Powder and Suspension Feedstocks
Authors: Michalak Monika , Sokołowski Paweł , Szala Mirosław , Walczak Mariusz , Łatka Leszek , Toma Filofteia-Laura , Björklund Stefan
Published: July 2021

Thermally sprayed ceramic coatings are applied for the protection of surfaces that are exposed mainly to wear, high temperatures, and corrosion. In recent years, great interest has been garnered by spray processes with submicrometric and nanometric feedstock materials, due to the refinement of the structure and improved coating properties. This paper compares the microstructure and tribological properties of alumina coatings sprayed using conventional atmospheric plasma spraying (APS), and various methods that use finely grained suspension feedstocks, namely, suspension plasma spraying (SPS) and suspension high-velocity oxy-fuel spraying (S-HVOF). Furthermore, the suspension plasma-sprayed Al2O3 coatings have been deposited with radial (SPS) and axial (A-SPS) feedstock injection. The results showed that all suspension-based coatings demonstrated much better wear resistance than the powder-sprayed ones. S-HVOF and axial suspension plasma spraying (A-SPS) allowed for the deposition of the most dense and homogeneous coatings. Dense-structured coatings with low porosity (4 vol.%) and good cohesion to the metallic substrate, containing a high content of α–Al2O3 phase (56 vol.%) and a very low wear rate (0.2 ± 0.04 mm3 × 10−6/(N∙m)), were produced with the S-HVOF method. The wear mechanism of ceramic coatings included the adhesive wear mode supported by the fatigue-induced material delamination. Moreover, the presence of wear debris and tribofilm was confirmed. Finally, the coefficient of friction for the coatings was in the range between 0.44 and 0.68, with the highest values being recorded for APS sprayed coatings.
Microstructure and Oxidation Behavior of Anti-Oxidation Coatings on Mo-Based Alloys through HAPC Process: A Review
Authors: Fu Tao , Cui Kunkun , Zhang Yingyi , Wang Jie , Zhang Xu , Shen Fuqiang , Yu Laihao , Mao Haobo
Published: July 2021

Mo and Mo-based alloys are important aerospace materials with excellent high temperature mechanical properties. However, their oxidation resistance is very poor at high temperature, and the formation of volatile MoO3 will lead to catastrophic oxidation failure of molybdenum alloy components. Extensive research on the poor oxidation problem has indicated that the halide activated pack cementation (HAPC) technology is an ideal method to solve the problem. In this work, the microstructure, oxide growth mechanism, oxidation characteristics, and oxidation mechanism of the HAPC coatings were summarized and analyzed. In addition, the merits and demerits of HPAC techniques are critically examined and the future scope of research in the domain is outlined.
Characterization of Internal Defects and Fiber Distribution of BFRC Based on the Digital Image Processing Technology
Authors: Chen Fengbin , Xu Bin , Jiao Huazhe , Ruan Zhuen , Liu Juanhong , Chen Xinming , Yang Liuhua , Li Zhen
Published: July 2021

Adding basalt fiber into concrete can significantly improve its mechanical properties. In order to explore the influence of basalt fiber content on the uniaxial compressive strength and splitting tensile strength of concrete and the mechanism of fiber action, this paper conducts compressive and splitting tensile tests on three kinds of basalt fiber concrete specimens with different fiber content and obtains the relationship between the macro mechanical properties and the fiber content. At the same time, with the help of CT scanning equipment and digital image processing technology, the microstructure of basalt fiber concrete with three groups of fiber content is reconstructed, and the pore, crack, and fiber distribution are quantitatively described using the calculation and processing function of the Avizo reconstruction software. The results show that when the optimal fiber content is 3 kg/m3, the improvement rates of uniaxial compressive strength and splitting tensile strength are 31.9% and 23.7%, respectively. The network structure formed by fiber in concrete has the best compactness and the least number of pores, with an average sphericity of 0.89 and an average pore volume of 20.26 μm3. Through analysis, it was found that the initial defects of basalt fiber concrete exist in the form of pores, and the addition of basalt fiber will destroy the large pore size of concrete, change the pore size distribution, and increase the average sphericity; The distribution of the fiber in the concrete is a three-dimensional network, and the distribution of the fiber in the initial defect distribution area is parallel to the direction of pore arrangement.
4-Phenylnaphtho[2,3-c]furan-1(3H)-one, 9-Phenylnaphtho[2,3-c]furan-1(3H)-one and 3a,4-Dihydro-9-phenylnaphtho[2,3-c]furan-1(3H)-one Crystal Structures
Authors: Merbouh Nabyl , Cassegrain Simon , Zhou Wen
Published: July 2021

The crystal structures are reported for two unsubstituted arylnaphthalene lactones, 4-phenylnaphtho[2,3-c]furan-1(3H)-one (2), 9-phenylnaphtho[2,3-c]furan-1(3H)-one (3) and a non-aromatic dihydro arylnaphthene lactone, 3a,4-dihydro-9-phenylnaphtho[2,3-c]furan-1(3H)-one (5). There are only minor differences in the geometrical parameters of these structures. However, in certain cases, both isomers of arylnaphthalene lactones (termed Type I and Type II) were found in the same asymmetric unit cell.
Experiments and Mechanical Simulation on Bubble Concrete: Studies on the Effects of Shape and Position of Hollow Bodies Mixed in Concrete
Authors: Yan Xiangdong , Chen Pei-Shan , Al-Fakih Amin , Liu Baoxin , Mohammed Bashar S. , Jin Jialiang
Published: July 2021

This paper proposes a new type of lightweight concrete called bubble concrete, which was developed by mixing concrete with high-strength hollow bodies. In the present study, concave and spherical steel hollow bodies were used not only to form multiple cavities in the concrete but also to transfer internal stresses. Through compression tests, the shape effects and distribution effects of the hollow bodies on the strength and Young’s modulus of concrete were investigated. In addition, the mechanical characteristics of the bubble concrete were simulated by nonlinear elastoplastic finite element analysis to study the stress distribution and failure mechanism. The results indicate that with the proper combination, bubble concrete can reduce its density to 1.971–2.003 g/cm3 (83.3–84.7%, compared to control concrete) and its strength reaches 27.536–28.954 N/mm2.
Symptom Burden of Patients with Advanced Pancreas Cancer (APC): A Provincial Cancer Institute Observational Study
Authors: Lelond Stephanie , Ward Julie , Lambert Pascal J. , Kim Christina A.
Published: July 2021

Patients with advanced pancreatic cancer (APC) experience many disease-related symptoms. ESAS-r measures the severity of 9 symptom domains and has been validated for use in the ambulatory oncology setting. We aimed to describe symptom burden at baseline for patients with APC treated with modern chemotherapy (CT), and to determine whether symptom burden at baseline is prognostic. Patients diagnosed with APC between 2012–2016, treated with ≥1 cycle of CT, who completed ≥1 ESAS-r were identified. Descriptive statistics were used to report symptom burden and common moderate-to-severe symptoms. A joint model was used to describe the trajectory of ESAS-r during follow-up while controlling for death. Multivariable Cox regression was used to identify independent predictors of death. Of 123 patients identified, the median age was 65 and 61% had metastatic disease. The median baseline ESAS-r total symptom distress score (TSDS) was 24. A total of 86% of patients had at least one symptom score of ≥4 at baseline, with the most common being: fatigue, nausea, anxiety, and shortness of breath. Median overall survival was 10.2 months. Baseline TSDS was not predictive for worse survival in the era of modern CT. Patients with APC have a high burden of cancer-associated symptoms and a high prevalence of moderate-to-severe symptoms. Early intervention has the potential to improve quality of life in this group of patients and should be investigated.
Technical Evaluation of the COBAS EGFR Semiquantitative Index (SQI) for Plasma cfDNA Testing in NSCLC Patients with EGFR Exon 19 Deletions
Authors: González de Aledo-Castillo José Manuel , Serhir-Sgheiri Samira , Calbet-Llopart Neus , Arcocha Ainara , Jares Pedro , Reguart Noemí , Puig-Butillé Joan Antón
Published: July 2021

The cobas® EGFR Test provides a semiquantitative index (SQI) that reflects the proportion of mutated versus wild-type copies of the EGFR gene in plasma. The significance of SQI as an indirect measure of the variant allele frequency (VAF) or mutated copies/mL remains unclear. The aim of this study was to evaluate the correlation of SQI with the VAF and the number of mutated copies/mL obtained by a digital droplet PCR (ddPCR) test in NSCLC samples. The study included 118 plasma samples from a retrospective cohort of 25 stage IV adenocarcinoma patients with EGFR exon 19 deletions (Ex19Del), obtained before and during tyrosine kinase inhibitor (TKI) treatment. Both SQI and VAF and SQI and mutated copies/mL showed the same significant correlation (r2 = 0.79, p < 0.00001) across the whole study cohort. We found better correlation in samples collected at the baseline between SQI and VAF (r2 = 0.94, p < 0.00001) and SQI and mutated copies/mL (r2 = 0.97, p < 0.00001) compared to samples collected during TKI treatment: r2 = 0.76; p < 0.00001 for SQI and VAF and r2 = 0.75; p < 0.00001 for SQI and mutated copies/mL. The study indicates that SQI is a robust quantitative indirect measure of VAF and the number of mutated copies/mL in plasma from patients with an EGFR Ex19Del mutation. Further studies are desirable to assess the SQI cut-off values related to the clinical status of the patient.
Sudden Unexpected Death Associated with Arrhythmogenic Cardiomyopathy: Study of the Cardiac Conduction System
Authors: Ottaviani Giulia , Alfonsi Graziella , Ramos Simone G. , Buja L. Maximilian
Published: July 2021

A retrospective study was conducted on pathologically diagnosed arrhythmogenic cardiomyopathy (ACM) from consecutive cases over the past 34 years (n = 1109). The anatomo-pathological analyses were performed on 23 hearts diagnosed as ACM (2.07%) from a series of 1109 suspected cases, while histopathological data of cardiac conduction system (CCS) were available for 15 out of 23 cases. The CCS was removed in two blocks, containing the following structures: Sino-atrial node (SAN), atrio-ventricular junction (AVJ) including the atrio-ventricular node (AVN), the His bundle (HB), the bifurcation (BIF), the left bundle branch (LBB) and the right bundle branch (RBB). The ACM cases consisted of 20 (86.96%) sudden unexpected cardiac death (SUCD) and 3 (13.04%) native explanted hearts; 16 (69.56%) were males and 7 (30.44%) were females, ranging in age from 5 to 65 (mean age ± SD, 36.13 ± 16.06) years. The following anomalies of the CCS, displayed as percentages of the 15 ACM SUCD cases in which the CCS has been fully analyzed, have been detected: Hypoplasia of SAN (80%) and/or AVJ (86.67%) due to fatty-fibrous involvement, AVJ dispersion and/or septation (46.67%), central fibrous body (CFB) hypoplasia (33.33%), fibromuscular dysplasia of SAN (20%) and/or AVN (26.67%) arteries, hemorrhage and infarct-like lesions of CCS (13.33%), islands of conduction tissue in CFB (13.33%), Mahaim fibers (13.33%), LBB block by fibrosis (13.33%), AVN tongue (13.33%), HB duplicity (6.67%%), CFB cartilaginous meta-hyperplasia (6.67%), and right sided HB (6.67%). Arrhythmias are the hallmark of ACM, not only from the fatty-fibrous disruption of the ventricular myocardium that accounts for reentrant ventricular tachycardia, but also from the fatty-fibrous involvement of CCS itself. Future research should focus on application of these knowledge on CCS anomalies to be added to diagnostic criteria or at least to be useful to detect the patients with higher sudden death risks.
Long-Term Impact of Wind Erosion on the Particle Size Distribution of Soils in the Eastern Part of the European Union
Authors: Lackóová Lenka , Pokrývková Jozefína , Kozlovsky Dufková Jana , Policht-Latawiec Agnieszka , Michałowska Krystyna , Dąbrowska Jolanta
Published: July 2021

Wind erosion is the leading cause of soil degradation and air pollution in many regions of the world. As wind erosion is controlled by climatic factors, research on this phenomenon is urgently needed in soil and land management in order to better adapt to climate change. In this paper, the impact of wind erosion on the soil surface in relation to particle size distribution was investigated. Changes in percentage of sand, silt and clay fractions based on historical KPP data (1961–1970), LUCAS data base (2009), and field measurements (2016) were analysed in five cadastral areas impacted by wind erosion (Záhorie Lowlands, Slovakia). With the use of GIS tools, models of spatial distribution of sand, silt, clay and erodible fraction (EF) content were developed based on those measurements. Our findings proved that soil texture change driven by wind erosion could happen relatively quickly, and a significant proportion of soil fine particles may be carried away within a few years. The results indicate that the soil surface became much rougher over the period of more than 50 years, but also that the accumulation of fraction of the silt particles occurred in most of the areas affected by the erosive effect.
Benchmarking Transfer Entropy Methods for the Study of Linear and Nonlinear Cardio-Respiratory Interactions
Authors: Rozo Andrea , Morales John , Moeyersons Jonathan , Joshi Rohan , Caiani Enrico G. , Borzée Pascal , Buyse Bertien , Testelmans Dries , Van Huffel Sabine , Varon Carolina
Published: July 2021

Transfer entropy (TE) has been used to identify and quantify interactions between physiological systems. Different methods exist to estimate TE, but there is no consensus about which one performs best in specific applications. In this study, five methods (linear, k-nearest neighbors, fixed-binning with ranking, kernel density estimation and adaptive partitioning) were compared. The comparison was made on three simulation models (linear, nonlinear and linear + nonlinear dynamics). From the simulations, it was found that the best method to quantify the different interactions was adaptive partitioning. This method was then applied on data from a polysomnography study, specifically on the ECG and the respiratory signals (nasal airflow and respiratory effort around the thorax). The hypothesis that the linear and nonlinear components of cardio-respiratory interactions during light and deep sleep change with the sleep stage, was tested. Significant differences, after performing surrogate analysis, indicate an increased TE during deep sleep. However, these differences were found to be dependent on the type of respiratory signal and sampling frequency. These results highlight the importance of selecting the appropriate signals, estimation method and surrogate analysis for the study of linear and nonlinear cardio-respiratory interactions.
IIT’s Scientific Counter-Revolution: A Neuroscientific Theory’s Physical and Metaphysical Implications
Authors: Fallon Francis , Blackmon James C.
Published: July 2021

IIT includes commitments about the very nature of physical reality, a fact both highly unusual for an empirical theory within neuroscience, and surprisingly underappreciated within the literature. These commitments are intimately tied to the theory; they are not incidental. This paper demonstrates as much by raising certain objections in a “naive” way, and then exposing how the principled IIT responses would rely upon metaphysical positions. Along the way we draw on the IIT literature for support for these interpretations, but also point to a need for elaboration and clarification. Section 1 applies the Placement Argument in a way that leads to problem involving zombies, treated in Section 2. Section 3 frames the zombie problem as an apparent dilemma, and addresses that dilemma by drawing on claims in the IIT literature concerning physical reality. Section 4 raises a related dilemma and treats it in a way that dovetails with the treatment in Section 3 of physical reality. All of this underscores not just the breadth of IIT, but the relevance of this breadth to a full consideration of IIT’s merits.
A Probe into the Status of the Oil Palm Sector in the Malaysian Value Chain
Authors: Said Fathin , Syed Roslan Sharifah , Zaidi Mohd , Yaakub Mohd
Published: July 2021

A ban on palm oil imports by the European Union has become a problematic issue, especially for palm oil producers’ countries. Oil palm has been widely used in many sub-sectors, and any changes in the production side may affect many sectors that use oil palm as an input factor in their productions. This study explores the chain of the oil palm sector on the other sub-sectors in Malaysia by using a value-added multiplier method and network modeling. The study focuses on the specific oil palm sub-sector and oils and fats sub-sector in the Malaysian economic structure based on the Malaysian Input-Output 2015 Table. Network visualization and all the analyses involving network methods were developed and performed using UCINET and GEPHI software. The value-added multiplier results explained that the net value between output multiplier and import multiplier is vital to depict the real impact of net resources used as an input factor in the oils and fats and oil palm sub-sectors. The high-density value level shows that the Malaysian oil palm sector has high connectivity in the economic system. From the network visualization analysis, the oils and fats sub-sector has a high level of integration with other sectors within the network. Meanwhile, the oil palm sub-sector categorized in the periphery structure group has a low level of integration in the input-output network. This is due to the high value-added demand for oil palm in the oils and fats sub-sector in the manufacturing sector. Overall, most of the sub-sectors in Malaysia are highly interconnected due to the high clustering ratio. Therefore, ensuring sufficient oil palm production is vital for sustainable production of other sub-sectors.
A Blended Learning Approach for an Introductory Computer Science Course
Authors: Förster Anna , Dede Jens , Udugama Asanga , Förster Alexander , Helms Daniel , Kniefs Louis , Müller Julia , Gerken Lars , Richter Franziska , Kulmann Jan
Published: July 2021

In this paper, we present our experience with redesigning an introductory computer science course for (electrical) engineers with blended learning concepts. It is a large mandatory course with eight credit points over the course of two semesters, where first year electrical engineers learn how to program with Arduino, C and Python. Additionally, they need to cover basic computer science concepts such as binary numbers, Boolean algebra, encodings, finite state machines and object-oriented programming. We designed the course to cover the fields that are most relevant to our students’ future careers. With the new format, students declare they are much more engaged with the course, they drop the course less often and they actually achieve better exam results. We completely re-structured the course, introduced inverted classroom elements and hackathons and we continuously optimized and adapted the course. The main focus is on hands-on-experience and teamwork, which we mostly achieve by the use of hackathons. In this paper, we described the contents and teaching concepts of the course and we discussed the achieved results.
“It’s Like Being Back in GCSE Art”—Engaging with Music, Film-Making and Boardgames. Creative Pedagogies within Youth Work Education
Authors: Howard Frances
Published: July 2021

Creative pedagogies within youth work practice are well established. Practitioners working with young people are often called upon to utilise their own personal and professional ‘toolboxes’, as a way of supporting ‘Creative Arts Youth Work’. However, within Higher Education (HE), creative methods for teaching and learning within the university context are often overlooked. The problem posed by this article is: how can HE ‘catch-up’ with more advanced pedagogies in the field of practice? Despite a recent focus on the personalisation of learning within HE, how can arts-based pedagogies, including digital storytelling, be drawn upon to enhance the learning experience? This article reports on three areas of pedagogical innovation engaged with by students undertaking the Youth Studies degree at Nottingham Trent University. Three experimental initiatives are explored, which assisted in educating informal educators, through creative learning techniques. Engaging with music, film-making and boardgames are given as examples of creative pedagogy, reporting on both my own practical experience in organising these activities and student feedback. Results showed that the symbiosis of creative pedagogies with relational and experiential learning, key tenets of youth work practice, offered expressive and authentic conditions for learning that are based upon student’s experiences. Therefore, there is much to learn from youth work courses within HE, not only in terms of engaging and encouraging students through creativity, but also setting the scene for the future of creative youth work practice.
An Analysis of Education Reforms and Assessment in the Core Subjects Using an Adapted Maslow’s Hierarchy: Pre and Post COVID-19
Authors: Ansorger Jennifer
Published: July 2021

Through the lens of an adapted Maslow’s hierarchy of needs, I have analyzed (1) the impact of the three main educational reforms of the 20th and 21st centuries on culturally and linguistically diverse (CLD)and low-socioeconomic (SES)students in the core subjects up to the COVID-19 pandemic; (2) the efficacy of current classroom assessment practices, and (3) a brief reimagining of how changing equity standards in teaching and assessment post-COVID-19 could aid in CLD and low-SES students achieving a higher self-esteem level. I contend that student success, or self-esteem, can only be achieved by first satisfying the needs at the lower hierarchy levels. By analyzing CLD and SES students’ school experiences, educators and policy-makers can extrapolate the requirements for inclusive, rigorous, and responsive assessments that recognize students’ needs and utilize their cultural and linguistic diversity. As states begin the shift from remote learning back to face-to-face in the fall, more significant considerations of CLD and low-SES students must be ensured.
Ultralow Voltage FinFET- Versus TFET-Based STT-MRAM Cells for IoT Applications
Authors: Garzón Esteban , Lanuzza Marco , Taco Ramiro , Strangio Sebastiano
Published: July 2021

Spin-transfer torque magnetic tunnel junction (STT-MTJ) based on double-barrier magnetic tunnel junction (DMTJ) has shown promising characteristics to define low-power non-volatile memories. This, along with the combination of tunnel FET (TFET) technology, could enable the design of ultralow-power/ultralow-energy STT magnetic RAMs (STT-MRAMs) for future Internet of Things (IoT) applications. This paper presents the comparison between FinFET- and TFET-based STT-MRAM bitcells operating at ultralow voltages. Our study is performed at the bitcell level by considering a DMTJ with two reference layers and exploiting either FinFET or TFET devices as cell selectors. Although ultralow-voltage operation occurs at the expense of reduced reading voltage sensing margins, simulations results show that TFET-based solutions are more resilient to process variations and can operate at ultralow voltages (<0.5 V), while showing energy savings of 50% and faster write switching of 60%.
Indoor 3D Localization Scheme Based on BLE Signal Fingerprinting and 1D Convolutional Neural Network
Authors: Yang Shangyi , Sun Chao , Kim Youngok
Published: July 2021

Indoor localization schemes have significant potential for use in location-based services in areas such as smart factories, mixed reality, and indoor navigation. In particular, received signal strength (RSS)-based fingerprinting is used widely, given its simplicity and low hardware requirements. However, most studies tend to focus on estimating the 2D position of the target. Moreover, it is known that the fingerprinting scheme is computationally costly, and its positioning accuracy is readily affected by random fluctuations in the RSS values caused by fading and the multipath effect. We propose an indoor 3D localization scheme based on both fingerprinting and a 1D convolutional neural network (CNN). Instead of using the conventional fingerprint matching method, we transform the 3D positioning problem into a classification problem and use the 1D CNN model with the RSS time-series data from Bluetooth low-energy beacons for classification. By using the 1D CNN with the time-series data from multiple beacons, the inherent drawback of RSS-based fingerprinting, namely, its susceptibility to noise and randomness, is overcome, resulting in enhanced positioning accuracy. To evaluate the proposed scheme, we developed a 3D positioning system and performed comprehensive tests, whose results confirmed that the scheme significantly outperforms the conventional common spatial pattern classification algorithm.
UHNVM: A Universal Heterogeneous Cache Design with Non-Volatile Memory
Authors: Li Xiaochang , Zhai Zhengjun
Published: July 2021

During the recent decades, non-volatile memory (NVM) has been anticipated to scale up the main memory size, improve the performance of applications, and reduce the speed gap between main memory and storage devices, while supporting persistent storage to cope with power outages. However, to fit NVM, all existing DRAM-based applications have to be rewritten by developers. Therefore, the developer must have a good understanding of targeted application codes, so as to manually distinguish and store data fit for NVM. In order to intelligently facilitate NVM deployment for existing legacy applications, we propose a universal heterogeneous cache hierarchy which is able to automatically select and store the appropriate data of applications for non-volatile memory (UHNVM), without compulsory code understanding. In this article, a program context (PC) technique is proposed in the user space to help UHNVM to classify data. Comparing to the conventional hot or cold files categories, the PC technique can categorize application data in a fine-grained manner, enabling us to store them either in NVM or SSDs efficiently for better performance. Our experimental results using a real Optane dual-inline-memory-module (DIMM) card show that our new heterogeneous architecture reduces elapsed times by about 11% compared to the conventional kernel memory configuration without NVM.
A Comparison of Time-Domain Implementation Methods for Fractional-Order Battery Impedance Models
Authors: Ospina Agudelo Brian , Zamboni Walter , Monmasson Eric
Published: July 2021

This paper is a comparative study of the multiple RC, Oustaloup and Grünwald–Letnikov approaches for time domain implementations of fractional-order battery models. The comparisons are made in terms of accuracy, computational burden and suitability for the identification of impedance parameters from time-domain measurements. The study was performed in a simulation framework and focused on a set of ZARC elements, representing the middle frequency range of Li-ion batteries’ impedance. It was found that the multiple RC approach offers the best accuracy–complexity compromise, making it the most interesting approach for real-time battery simulation applications. As for applications requiring the identification of impedance parameters, the Oustaloup approach offers the best compromise between the goodness of the obtained frequency response and the accuracy–complexity requirements.
Numerical Study of Thermal-Hydraulic Performance of a New Spiral Z-Type PCHE for Supercritical CO2 Brayton Cycle
Authors: Xu Tingting , Zhao Hongxia , Wang Miao , Qi Jianhui
Published: July 2021

Printed circuit heat exchangers (PCHEs) have the characteristics of high temperature and high pressure resistance, as well as compact structure, so they are widely used in the supercritical carbon dioxide (S-CO2) Brayton cycle. In order to fully study the heat transfer process of the Z-type PCHE, a numerical model of traditional Z-type PCHE was established and the accuracy of the model was verified. On this basis, a new type of spiral PCHE (S-ZPCHE) is proposed in this paper. The segmental design method was used to compare the pressure changes under 5 different spiral angles, and it was found that increasing the spiral angle θ of the spiral structure will reduce the pressure drop of the fluid. The effects of different spiral angles on the thermal-hydraulic performance of S-ZPCHE were compared. The results show that the pressure loss of fluid is greatly reduced, while the heat transfer performance is slightly reduced, and it was concluded that the spiral angle of 20° is optimal. The local fluid flow states of the original structure and the optimal structure were compared to analyze the reason for the pressure drop reduction effect of the optimal structure. Finally, the performance of the optimal structure was analyzed under variable working conditions. The results show that the effect of reducing pressure loss of the new S-ZPCHE is more obvious in the low Reynolds number region.
Pore-Filled Proton-Exchange Membranes with Fluorinated Moiety for Fuel Cell Application
Authors: Song Hyeon-Bee , Park Jong-Hyeok , Park Jin-Soo , Kang Moon-Sung
Published: July 2021

Proton-exchange membrane fuel cells (PEMFCs) are the heart of promising hydrogen-fueled electric vehicles, and should lower their price and further improve durability. Therefore, it is necessary to enhance the performances of the proton-exchange membrane (PEM), which is a key component of a PEMFC. In this study, novel pore-filled proton-exchange membranes (PFPEMs) were developed, in which a partially fluorinated ionomer with high cross-linking density is combined with a porous polytetrafluoroethylene (PTFE) substrate. By using a thin and tough porous PTFE substrate film, it was possible to easily fabricate a composite membrane possessing sufficient physical strength and low mass transfer resistance. Therefore, it was expected that the manufacturing method would be simple and suitable for a continuous process, thereby significantly reducing the membrane price. In addition, by using a tri-functional cross-linker, the cross-linking density was increased. The oxidation stability was greatly enhanced by introducing a fluorine moiety into the polymer backbone, and the compatibility with the perfluorinated ionomer binder was also improved. The prepared PFPEMs showed stable PEMFC performance (as maximum power density) equivalent to 72% of Nafion 212. It is noted that the conductivity of the PFPEMs corresponds to 58–63% of that of Nafion 212. Thus, it is expected that a higher fuel cell performance could be achieved when the membrane resistance is further lowered.
Synthesis and Application of Ternary Nanofluid for Photovoltaic-Thermal System: Comparative Analysis of Energy and Exergy Performance with Single and Hybrid Nanofluids
Authors: ADUN Humphrey , Mukhtar Mustapha , Adedeji Micheal , Agwa Terfa , Ibrahim Kefas Hyelda , Bamisile Olusola , Dagbasi Mustafa
Published: July 2021

The amelioration of photovoltaic (PV) and photovoltaic/thermal (PV/T) systems have garnered increased research interest lately, more so due to the discovery of the thermal property augmentation of nanofluids. The overarching goal of this study is to conduct a comparative analysis of mono, hybrid, and ternary hybrid nanofluids utilized as fluids for heat transfer applications and particularly as cooling mediums in PV/T applications. Al2O3, ZnO, Al2O3-ZnO, and Al2O3-ZnO-Fe3O4 nanofluids are synthesized at 1% volume concentration using the two-step method. The zeta potential tests carried out showed that the fluids have high stability. The numerical model developed in this study was validated using real data culled from Cyprus International University. The findings in this study showed that the Al2O3-ZnO-Fe3O4 ternary hybrid nanofluid and ZnO mono nanofluid were more efficient heat transfer fluids for the PV/T system. The optimum relative electrical PV/T efficiency against that of the PV is 8.13% while the electrical and thermal enhancement recorded in this study was 1.79% and 19.06%, respectively, measured for the ternary hybrid nanofluid based PV/T system. This present study shows that despite the limitation of pumping power and pressure drop associated with nanofluid in thermal systems, the close performance evaluation criterion values as compared with water is positive for practical utilization of nanofluid in PV/T systems.
Complementary Feature Extractions for Event Identification in Power Systems Using Multi-Channel Convolutional Neural Network
Authors: Kim Do-In
Published: July 2021

This paper presents an event identification process in complementary feature extractions via convolutional neural network (CNN)-based event classification. The CNN is a suitable deep learning technique for addressing the two-dimensional power system data as it directly derives information from a measurement signal database instead of modeling transient phenomena, where the measured synchrophasor data in the power systems are allocated by time and space domains. The dynamic signatures in phasor measurement unit (PMU) signals are analyzed based on the starting point of the subtransient signals, as well as the fluctuation signature in the transient signal. For fast decision and protective operations, the use of narrow band time window is recommended to reduce the acquisition delay, where a wide time window provides high accuracy due to the use of large amounts of data. In this study, two separate data preprocessing methods and multichannel CNN structures are constructed to provide validation, as well as the fast decision in successive event conditions. The decision result includes information pertaining to various event types and locations based on various time delays for the protective operation. Finally, this work verifies the event identification method through a case study and analyzes the effects of successive events in addition to classification accuracy.
Characterization of TSO and DSO Grid System Services and TSO-DSO Basic Coordination Mechanisms in the Current Decarbonization Context
Authors: Silva Ricardo , Alves Everton , Ferreira Ricardo , Villar José , Gouveia Clara
Published: July 2021

Power systems rely on ancillary services (ASs) to ensure system security and stability. Until recently, only the conventional power generation resources connected to the transmission grids were allowed to provide these ASs managed by the transmission system operators (TSOs), while distribution system operators (DSOs) had a more passive role, focused on guaranteeing distribution capacity to bring power to final consumers with enough quality. Now, with the decarbonization, digitalization and decentralization processes of the electrical networks, the growing integration of distributed energy resources (DERs) in distribution grids are displacing conventional generation and increasing the complexity of distribution networks’ operation, requiring the implementation of new active and coordinated management strategies between TSOs and DSOs. In this context, DERs are becoming potential new sources of flexibility for both TSOs and DSOs in helping to manage the power system. This paper proposes a systematic characterization of both traditional and potentially new ASs for TSOs, and newly expected DSO local system services to support the new distribution grid operation paradigm, reviewing, in addition, the main TSO-DSO coordination mechanisms.