bluuebunny/crossref_metadata_2025 huggingface dataset:
Maleic Anhydride Modified Dicyclopentadiene Resin for Improving Wet Skid Resistance of Silica Filled SSBR/BR Composites
Authors: Huang Ruoming , Pan Qiwei , Chen Zhaohui , Feng Kunhao
Published: June 2020

As commercial rubber in tires, silica-filled solution-polymerized styrene-butadiene rubber/butadiene rubber (SSBR/BR) compounds exhibited preferable wet skid resistance (WSR) properties, which could be further enhanced by the incorporation of some oligomeric resins. However, the untreated dicyclopentadiene (DCPD) resin shows a slight improvement in wet friction even if the good compatibility between DCPD and SBR owing to their common cyclic structures. For this problem to be addressed, we aimed to enhance its resin-silica interaction by reaction with maleic anhydride (MAH). In detail, the effect of MAH content on WSR, curing characteristics, physical-mechanical properties of the silica-filled SSBR/BR composites was investigated. When the MAH content is 4 wt% in the modified DCPD resin, the maximum enhancement of about 15% in tan δ values at 0 °C, as well as that of 17% in British pendulum skidding tester (BPST) index is obtained, indicating a desirable improvement in WSR. In addition of these two commonly used methods, water contact angles of the vulcanizates increase gradually with increasing MAH content, further confirming the remarkable performance of modified DCPD resin in WSR.
Physical Changes during Post-Mortem Ageing of High-Value Impala (Aepyceros Melampus) Steaks
Authors: Needham Tersia , Engels Retha A. , Hoffman Louwrens C.
Published: June 2020

Antelope meat production is rapidly growing, not only due to their adaptation to marginal land usage, but also because of its favorable nutritional properties and free-range production. However, limited information is available on the meat quality and processing potential of game meat for commercial consumption. The objective of this study was to determine the ageing period to achieve maximum tenderness of longissimus thoracis et lumborum (LTL) muscles of impala. The LTL muscles of 11 male and 11 female impala were harvested, and divided into eight portions. Each portion was randomly allocated to 1, 2, 4, 6, 8, 10, 12, or 14 days of wet-ageing (4 °C) in vacuum packaging. The meat pH, color, weep loss, cooking loss, and Warner–Bratzler shear force were measured throughout ageing. Initially the ageing profile differed depending on the sex of the animal from which the muscle was harvested; however, after 8 days of ageing, maximum tenderness was reached (13.5 ± 0.91 N) and no further sex differences were seen. Ageing improved the surface color of all meat until day 8, after which discoloration occurred. Therefore, it is recommended that impala LTL steaks should be wet-aged at 4 °C for eight days to achieve maximum tenderness and minimize sex variability.
Spectral and Nonlinear Analysis of Electrodermal Activity in Adolescent Anorexia Nervosa
Authors: Visnovcova Zuzana , Bona Olexova Lucia , Sekaninova Nikola , Ondrejka Igor , Hrtanek Igor , Cesnekova Dana , Kelcikova Simona , Farsky Ivan , Tonhajzerova Ingrid
Published: June 2020

Anorexia nervosa (AN) is an eating disorder with increasing prevalence in childhood and adolescence. Sympathetic dysregulation is supposed to be the underlying mechanism of increased cardiovascular risk in AN. Thus, we assess the electrodermal activity (EDA) as a non-invasive index of sympathetic cholinergic activity using linear and nonlinear analysis in adolescent AN with the aim of detecting potential biomarkers for AN-linked cardiovascular risk. We examined 25 adolescent girls with AN and 25 age-matched controls. EDA was continuously recorded during a 5-min resting phase. Evaluated parameters were: time-domain (skin conductance level, non-specific skin conductance responses), frequency-domain (EDA in very low, low, sympathetic, high and very high frequency bands) and nonlinear (approximate, sample, symbolic information entropies, detrended fluctuation analysis (DFA)) parameters of EDA and peripheral skin temperature. Our findings revealed lower EDA values indicating a decrease in the sympathetic nervous activity in female adolescents with the acute phase of AN. Further, we found higher nonlinear index DFA in AN vs. controls. We assumed that nonlinear index DFA could provide novel and independent information on the complex sympathetic regulatory network. We conclude that the parameters of complex EDA analysis could be used as sensitive biomarkers for the assessment of sympathetic cholinergic dysregulation as a risk factor for AN-linked cardiovascular morbidity.
TranScreen: Transfer Learning on Graph-Based Anti-Cancer Virtual Screening Model
Authors: Salem Milad , Khormali Aminollah , Arshadi Arash Keshavarzi , Webb Julia , Yuan Jiann-Shiun
Published: June 2020

Deep learning’s automatic feature extraction has proven its superior performance over traditional fingerprint-based features in the implementation of virtual screening models. However, these models face multiple challenges in the field of early drug discovery, such as over-training and generalization to unseen data, due to the inherently unbalanced and small datasets. In this work, the TranScreen pipeline is proposed, which utilizes transfer learning and a collection of weight initializations to overcome these challenges. An amount of 182 graph convolutional neural networks are trained on molecular source datasets and the learned knowledge is transferred to the target task for fine-tuning. The target task of p53-based bioactivity prediction, an important factor for anti-cancer discovery, is chosen to showcase the capability of the pipeline. Having trained a collection of source models, three different approaches are implemented to compare and rank them for a given task before fine-tuning. The results show improvement in performance of the model in multiple cases, with the best model increasing the area under receiver operating curve ROC-AUC from 0.75 to 0.91 and the recall from 0.25 to 1. This improvement is vital for practical virtual screening via lowering the false negatives and demonstrates the potential of transfer learning. The code and pre-trained models are made accessible online.
Inhibition on JNK Mimics Silencing of Wnt-11 Mediated Cellular Response in Androgen-Independent Prostate Cancer Cells
Authors: Arisan Elif Damla , Rencuzogullari Ozge , Keskin Buse , Grant Guy H. , Uysal-Onganer Pinar
Published: June 2020

Prostate cancer (PCa) is one of the most common cancers among men, and one of the leading causes of cancer death for men. The c-Jun N-terminal kinase (JNK) pathway is required for several cellular functions, such as survival, proliferation, differentiation, and migration. Wnt-11, a member of the Wnt family, has been identified for its upregulation in PCa; however, downstream signalling of Wnt-11 remains to be fully characterized. In this study, we investigated the role of the JNK pathway as a potential downstream factor for Wnt-11 signalling. For this purpose, LNCaP, DU145, and PC-3 PCa cells and normal epithelial PNT1A cells were treated with a specific JNK kinase inhibitor: JNKVIII. Our results showed that JNK inhibition decreased mitochondrial membrane potential and promoted cell death in a cell type-dependent manner. We found that JNK inhibition led to an increase in autophagy and prevented epithelial–mesenchymal transition (EMT) in independently growing androgen cells. JNK inhibition and the silencing of Wnt-11 showed similar responses in DU145 and PC-3 cells and decreased metastasis-related biomarkers, cell migration, and invasion. Overall, our results suggest that JNK signalling plays a significant role in the pathophysiology of PCa by mediating Wnt-11 induced signals. Our data highlights that both the JNK pathway and Wnt-11 could be a useful therapeutic target for the combinatory application of current PCa.
A New TGF-β1 Inhibitor, CTI-82, Antagonizes Epithelial–Mesenchymal Transition through Inhibition of Phospho-SMAD2/3 and Phospho-ERK
Authors: Jeong Ji-Hoon , Kim Hyunhee , Park Seung-Ho , Park Hayeon , Jeong Minseok , Kwak Sungmin , Sung Gi-Jun , Song Ji-Hye , Na Younghwa , Choi Kyung-Chul
Published: June 2020

Transforming growth factor-β1 (TGF-β1) is highly expressed in the tumor microenvironment and known to play a multifunctional role in cancer progression. In addition, TGF-β1 promotes metastasis by inducing epithelial–mesenchymal transition (EMT) in a variety of tumors. Thus, inhibition of TGF-β1 is considered an important strategy in the treatment of cancer. In most tumors, TGF-β1 signal transduction exhibits modified or non-functional characteristics, and TGF-β1 inhibitors have various inhibitory effects on cancer cells. Currently, many studies are being conducted to develop TGF-β1 inhibitors from non-toxic natural compounds. We aimed to develop a new TGF-β1 inhibitor to suppress EMT in cancer cells. As a result, improved chalcone-like chain CTI-82 was identified, and its effect was confirmed in vitro. We showed that CTI-82 blocked TGF-β1-induced EMT by inhibiting the cell migration and metastasis of A549 lung cancer cells. In addition, CTI-82 reduced the TGF-β1-induced phosphorylation of SMAD2/3 and inhibited the expression of various EMT markers. Our results suggest that CTI-82 inhibits tumor growth, migration, and metastasis.
Carnosine Activates Cellular Stress Response in Podocytes and Reduces Glycative and Lipoperoxidative Stress
Authors: Scuto Maria , Trovato Salinaro Angela , Modafferi Sergio , Polimeni Alessandra , Pfeffer Tilman , Weigand Tim , Calabrese Vittorio , Schmitt Claus Peter , Peters Verena
Published: June 2020

Carnosine improves diabetic complications, including diabetic nephropathy, in in vivo models. To further understand the underlying mechanism of nephroprotection, we studied the effect of carnosine under glucose-induced stress on cellular stress response proteins in murine immortalized podocytes, essential for glomerular function. High-glucose stress initiated stress response by increasing intracellular heat shock protein 70 (Hsp70), sirtuin-1 (Sirt-1), thioredoxin (Trx), glutamate-cysteine ligase (gamma-glutamyl cysteine synthetase; γ-GCS) and heme oxygenase-1 (HO-1) in podocytes by 30–50% compared to untreated cells. Carnosine (1 mM) also induced a corresponding upregulation of these intracellular stress markers, which was even more prominent compared to glucose for Hsp70 (21%), γ-GCS and HO-1 (13% and 20%, respectively; all p < 0.001). Co-incubation of carnosine (1 mM) and glucose (25 mM) induced further upregulation of Hsp70 (84%), Sirt-1 (52%), Trx (35%), γ-GCS (90%) and HO-1 (73%) concentrations compared to untreated cells (all p < 0.001). The glucose-induced increase in 4-hydroxy-trans-2-nonenal (HNE) and protein carbonylation was reduced dose-dependently by carnosine by more than 50% (p < 0.001). Although podocytes tolerated high carnosine concentrations (10 mM), high carnosine levels only slightly increased Trx and γ-GCS (10% and 19%, respectively, compared to controls; p < 0.001), but not Hsp70, Sirt-1 and HO-1 proteins (p not significant), and did not modify the glucose-induced oxidative stress response. In podocytes, carnosine induced cellular stress tolerance and resilience pathways and was highly effective in reducing high-glucose-induced glycative and lipoperoxidative stress. Carnosine in moderate concentrations exerted a direct podocyte molecular protective action.
Bioinformatic Analyses of miRNA–mRNA Signature during hiPSC Differentiation towards Insulin-Producing Cells upon HNF4α Mutation
Authors: Ghila Luiza , Bjørlykke Yngvild , Legøy Thomas Aga , Vethe Heidrun , Furuyama Kenichiro , Chera Simona , Ræder Helge
Published: June 2020

Mutations in the hepatocyte nuclear factor 4α (HNF4α) gene affect prenatal and postnatal pancreas development, being characterized by insulin-producing β-cell dysfunction. Little is known about the cellular and molecular mechanisms leading to β-cell failure as result of HNF4α mutation. In this study, we compared the miRNA profile of differentiating human induced pluripotent stem cells (hiPSC) derived from HNF4α+/Δ mutation carriers and their family control along the differentiation timeline. Moreover, we associated this regulation with the corresponding transcriptome profile to isolate transcript–miRNA partners deregulated in the mutated cells. This study uncovered a steep difference in the miRNA regulation pattern occurring during the posterior foregut to pancreatic endoderm transition, defining early and late differentiation regulatory windows. The pathway analysis of the miRNAome–transcriptome interactions revealed a likely gradual involvement of HNF4α+/Δ mutation in p53-mediated cell cycle arrest, with consequences for the proliferation potential, survival and cell fate acquisition of the differentiating cells. The present study is based on bioinformatics approaches and we expect that, pending further experimental validation, certain miRNAs deregulated in the HNF4α+/Δ cells would prove useful for therapy.
A Review of Micro-Based Systemic Risk Research from Multiple Perspectives
Authors: Bai Xiao , Sun Huaping , Lu Shibao , Taghizadeh-Hesary Farhad
Published: June 2020

The Covid-19 pandemic has brought about a heavy impact on the world economy, which arouses growing concerns about potential systemic risk, taking place in countries and regions. At this critical moment, it makes sense to interpret the systemic risk from the perspective of the financial crisis framework. By combing the latest research on systemic risks, we may arrive at some precautions relating to the current events. This literature review verifies the origin of systemic risk research. By comparing the retrieved and screened systemic literature with the relevant research on the financial crisis, more focus on the micro-foundations of systemic risk has been discovered. Besides, the measurement methods of systemic risks and the introduction of interdisciplinary methods have made the research in this field particularly active. This paper synthesizes the previous research conclusions to find the appropriate definition of systemic risk and combs the research literature of systemic risk from two lines: Firstly, conducting the division according to the sub-branch fields within the financial discipline and the relevant interdisciplinary research methods, which is helpful for scholars within and outside the discipline to have a more systematic understanding of the research in this field. Secondly predicting the research direction that can be expanded in this field.
Optimal Encoding in Stochastic Latent-Variable Models
Authors: Rule Michael E. , Sorbaro Martino , Hennig Matthias H.
Published: June 2020

In this work we explore encoding strategies learned by statistical models of sensory coding in noisy spiking networks. Early stages of sensory communication in neural systems can be viewed as encoding channels in the information-theoretic sense. However, neural populations face constraints not commonly considered in communications theory. Using restricted Boltzmann machines as a model of sensory encoding, we find that networks with sufficient capacity learn to balance precision and noise-robustness in order to adaptively communicate stimuli with varying information content. Mirroring variability suppression observed in sensory systems, informative stimuli are encoded with high precision, at the cost of more variable responses to frequent, hence less informative stimuli. Curiously, we also find that statistical criticality in the neural population code emerges at model sizes where the input statistics are well captured. These phenomena have well-defined thermodynamic interpretations, and we discuss their connection to prevailing theories of coding and statistical criticality in neural populations.
Design of a High Voltage Pulse Generator with Large Width Adjusting Range for Tumor Treatment
Authors: Rao Xin , Chen Xiaodong , Zhou Jun , Zhang Bo , Alfadhl Yasir
Published: June 2020

The unique biological effects stimulated by short pulsed electric field have many applications in tumor treatment, such as irreversible electroporation, electrochemotherapy, gene transfection and immune therapy. These biological effects require high voltage pulses with different pulse width in the range from nanoseconds to hundreds of microseconds. To fulfill this requirement, a compact high voltage pulse generator has been designed based on a switchable capacitor array and a SiC MOSFET switching array. The proposed pulse generator has one output channel with an adjustable pulse width from 100 ns to 100 µs, an amplitude range from 0 kV to 2 kV, a repetition rate less than 1.2 kHz and a voltage drop less than 5%. The mechanism of the stacked switches circuit was investigated, in connection with a switchable capacitor array. The introduction of a switchable capacitor array extends the pulse width from nanosecond scale and microsecond scale compared with other similar design methods. The pulse generator has been designed in simulation and implemented in experiment. The developed pulse generator provides a convenient and economical tool for the further studies of the unique biological effects stimulated by different pulsed electric fields for tumor treatment.
Exact Design Space Exploration Based on Consistent Approximations
Authors: Neubauer Kai , Beichler Benjamin , Haubelt Christian
Published: June 2020

The aim of design space exploration (DSE) is to identify implementations with optimal quality characteristics which simultaneously satisfy all imposed design constraints. Hence, besides searching for new solutions, a quality evaluation has to be performed for each design point. This process is typically very expensive and takes a majority of the exploration time. As nearly all the explored design points are sub-optimal, most of them get discarded after evaluation. However, evaluating a solution takes virtually the same amount of time for both good and bad ones. That way, a huge amount of computing power is literally wasted. In this paper, we propose a solution to the aforementioned problem by integrating efficient approximations in the background of a DSE engine in order to allow an initial evaluation of each solution. Only if the approximated quality indicates a promising candidate, the time-consuming exact evaluation is executed. The novelty of our approach is that (1) although the evaluation process is accelerated by using approximations, we do not forfeit the quality of the acquired solutions and (2) the integration in a background theory allows sophisticated reasoning techniques to prune the search space with the help of the approximation results. We have conducted an experimental evaluation of our approach by investigating the dependency of the accuracy of used approximations on the performance gain. Based on 120 electronic system level problem instances, we show that our approach is able to increase the overall exploration coverage by up to six times compared to a conservative DSE whenever accurate approximation functions are available.
Energy Harvesting Backpacks for Human Load Carriage: Modelling and Performance Evaluation
Authors: Huang Ledeng , Wang Ruishi , Yang Zhenhua , Xie Longhan
Published: June 2020

In recent years, there has been an increasing demand for portable power sources as people are required to carry more equipment for occupational, military, or recreational purposes. The energy harvesting backpack that moves relative to the human body, could capture kinetic energy from human walking and convert vertical oscillation into the rotational motion of the generators to generate electricity. In our previous work, a light-weight tube-like energy harvester (TL harvester) and a traditional frequency-tuneable backpack-based energy harvester (FT harvester) were proposed. In this paper, we discuss the power generation performance of the two types of energy harvesters and the energy performance of human loaded walking, while carrying energy harvesting backpacks, based on two different spring-mass-damper models. Testing revealed that the electrical power in the experiments showed similar trends to the simulation results, but the calculated electrical power and the net metabolic power were higher than that of the experiments. Moreover, the total cost of harvesting (TCOH), defined as additional metabolic power in watt required to generate 1 W of electrical power, could be negative, which indicated that there is a chance to generate 6.11 W of electricity without increasing the metabolic cost while carrying energy harvesting backpacks.
LC Impedance Source Bi-Directional Converter with Reduced Capacitor Voltages
Authors: Raveendhra Dogga , Dhaouadi Rached , Rehman Habibur , Mukhopadhyay Shayok
Published: June 2020

This paper proposes an LC (Inductor and Capacitor) impedance source bi-directional DC–DC converter by redesigning after rearranging the reduced number of components of a switched boost bi-directional DC–DC converter. This new converter with a conventional modulation scheme offers several unique features, such as a) a lower number of components and b) reduced voltage stress on the capacitor compared to existing topologies. The reduction of capacitor voltage stress has the potential of improving the reliability and enhancing converter lifespan. An analysis of the proposed converter was completed with the help of a mathematical model and state-space averaging models. The converter performance under different test conditions is compared with the conventional bi-directional DC–DC converter, Z-source converter, discontinuous current quasi Z-source converter, continuous current quasi Z-source converter, improved Z-source converter, switched boost converter, current-fed switched boost converter, and quasi switched boost converter in the Matlab Simulink environment. MATLAB/Simulink results demonstrate that the proposed converter has lesser components count and reduced capacitors’ voltage stresses when compared to the topologies mentioned above. A 24 V to 18 V LC-impedance source bi-directional converter and a conventional bidirectional converter are built to investigate the feasibility and benefits of the proposed topology. Experimental results reveal that capacitor voltage stresses, in the case of proposed topology are reduced by 75.00% and 35.80% in both boost and buck modes, respectively, compared to the conventional converter circuit.
Lung Nodule Classification Using Taguchi-Based Convolutional Neural Networks for Computer Tomography Images
Authors: Lin Cheng-Jian , Li Yu-Chi
Published: June 2020

Lung cancer occurs in the lungs, trachea, or bronchi. This cancer is often caused by malignant nodules. These cancer cells spread uncontrollably to other organs of the body and pose a threat to life. An accurate assessment of disease severity is critical to determining the optimal treatment approach. In this study, a Taguchi-based convolutional neural network (CNN) was proposed for classifying nodules into malignant or benign. For setting parameters in a CNN, most users adopt trial and error to determine structural parameters. This study used the Taguchi method for selecting preliminary factors. The orthogonal table design is used in the Taguchi method. The final optimal parameter combination was determined, as were the most significant parameters. To verify the proposed method, the lung image database consortium data set from the National Cancer Institute was used for analysis. The database contains a total of 16,471 images, including 11,139 malignant nodule images. The experimental results demonstrated that the proposed method with the optimal parameter combination obtained an accuracy of 99.6%.
Voltage Control Methodologies in Active Distribution Networks
Authors: Ilea Valentin , Bovo Cristian , Falabretti Davide , Merlo Marco , Arrigoni Carlo , Bonera Roberto , Rodolfi Marco
Published: June 2020

Renewable Energy Sources are becoming widely spread, as they are sustainable and low-carbon emission. They are mostly penetrating the MV Distribution Networks as Distributed Generators, which has determined the evolution of the networks’ control and supervision systems, from almost a complete lack to becoming fully centralized. This paper proposes innovative voltage control architectures for the distribution networks, tailored for different development levels of the control and supervision systems encountered in real life: a Coordinated Control for networks with basic development, and an optimization-based Centralized Control for networks with fully articulated systems. The Centralized Control fits the requirements of the network: the challenging harmonization of the generator’s capability curves with the regulatory framework, and modelling of the discrete control of the On-Load Tap Changer transformer. A realistic network is used for tests and comparisons with the Local Strategy currently specified by regulations. The proposed Coordinated Control gives much better results with respect to the Local Strategy, in terms of loss minimization and voltage violations mitigation, and can be used for networks with poorly developed supervision and control systems, while Centralized Control proves the best solution, but can be applied only in fully supervised and controlled networks.
Preliminary Study on the GWP Benchmark of Office Buildings in Poland Using the LCA Approach
Authors: Rucińska Joanna , Komerska Anna , Kwiatkowski Jerzy
Published: June 2020

The decarbonisation goal stated in the Energy Performance of Buildings Directive (EPBD) regarding the building sector will be achieved only if the whole building life-cycle is considered. To fulfil this requirement, a benchmark based on the life cycle assessment (LCA) must be integrated into the early planning phase of buildings by designers. The estimation of such indicators requires the development of a database of building assessments. In this study, an LCA of 11 office buildings in Poland was used to set average values that can be used as a benchmark. The LCA methodology based on the Building Research Establishment Environmental Assessment Method (BREEAM) certification was used. The analysis did not concentrate on one type of office building. The main objective was to investigate a possible range of total Global Warming Potential (GWP) index values normalized to the usable unit floor area. The importance of the GWP of individual life-cycle phases was also considered. The study shows that the used methodology is adequate for LCA benchmark estimation to set preliminary average values for office buildings in Poland.
Understanding Computational Methods for Solar Envelopes Based on Design Parameters, Tools, and Case Studies: A Review
Authors: Alkadri Miktha Farid , De Luca Francesco , Turrin Michela , Sariyildiz Sevil
Published: June 2020

The increasing population density in urban areas simultaneously impacts the trend of energy consumption in building sectors and the urban heat island (UHI) effects of urban infrastructure. Accordingly, passive design strategies to create sustainable buildings play a major role in addressing these issues, while solar envelopes prove to be a relevant concept that specifically considers the environmental performance aspects of a proposed building given their local contexts. As significant advances have been made over the past decades regarding the development and implementation of computational solar envelopes, this study presents a comprehensive review of solar envelopes while specifically taking into account design parameters, digital tools, and the implementation of case studies in various contextual settings. This extensive review is conducted in several stages. First, an investigation of the scope and procedural steps of the review is conducted to frame the boundary of the topic to be analyzed within the conceptual framework of solar envelopes. Second, comparative analyses between categorized design methods in parallel with a database of design parameters are conducted, followed by an in-depth discussion of the criteria for the digital tools and case studies extracted from the selected references. Third, knowledge gaps are identified, and the future development of solar envelopes is discussed to complete the review. This study ultimately provides an inclusive understanding for designers and architects regarding the progressive methods of the development of solar envelopes during the conceptual design stage.
An Evaluation of Energy Storage Cost and Performance Characteristics
Authors: Mongird Kendall , Viswanathan Vilayanur , Balducci Patrick , Alam Jan , Fotedar Vanshika , Koritarov Vladimir , Hadjerioua Boualem
Published: June 2020

The energy storage industry has expanded globally as costs continue to fall and opportunities in consumer, transportation, and grid applications are defined. As the rapid evolution of the industry continues, it has become increasingly important to understand how varying technologies compare in terms of cost and performance. This paper defines and evaluates cost and performance parameters of six battery energy storage technologies (BESS)—lithium-ion batteries, lead-acid batteries, redox flow batteries, sodium-sulfur batteries, sodium-metal halide batteries, and zinc-hybrid cathode batteries—four non-BESS storage systems—pumped storage hydropower, flywheels, compressed air energy storage, and ultracapacitors—and combustion turbines. Cost and performance information was compiled based on an extensive literature review, conversations with vendors and stakeholders, and costs of systems procured at sites across the United States. Detailed cost and performance estimates are presented for 2018 and projected out to 2025. Annualized costs were also calculated for each technology.
Gasification of Shenhua Bituminous Coal with CO2: Effect of Coal Particle Size on Kinetic Behavior and Ash Fusibility
Authors: Zhang Jinzhi , Wang Zhiqi , Zhao Ruidong , Wu Jinhu
Published: June 2020

Coal gasification is the process that produces valuable gaseous mixtures consisting primarily of H2 and CO, which can be used to produce liquid fuel and various kinds of chemicals. The literature shows that the effect of particle size on coal gasification and fusibility of coal ash is not clear. In this study, the gasification kinetics and ash fusibility of three coal samples with different particle size ranges were investigated. Thermogravimetric results of coal under a CO2 atmosphere showed that the whole weight loss process consisted of three stages: the loss of moisture, the release of volatile matter, and char gasification with CO2. Coal is a heterogeneous material containing impurities. Different grinding fineness leads to different liberation degrees for impurities. As for the effect of particle size on TG (thermogravimetry) curves, we found that the final solid residue amount was the largest for the coal sample with the smallest particle size. The Miura-Maki isoconversional model was proved to be appropriate to estimate the activation energy and its value experienced a slow increase when the particle size of raw coal increased. Further, we found that particle size had an important impact on ash fusion temperatures and small particle size resulted in higher ash fusion temperatures.
A CFD Investigation of a 2D Balanced Vane Pump Focusing on Leakage Flows and Multiphase Flow Characteristics
Authors: Lobsinger Thomas , Hieronymus Timm , Brenner Gunther
Published: June 2020

Vane pumps are often applied in automatic transmission systems of vehicles. Future applications require the oil pumps to be more efficient and to be able to handle multiphase flow pumping situations to a certain extend. To fulfill these requirements, efficient development tools are needed. Therefore, a less demanding computational 2D model of a fixed-type balanced vane pump was derived and numerically analyzed with the commercial computational fluid dynamics (CFD) software ANSYS CFX. The meshing of the rotating parts was done with TwinMesh, using a moving mesh approach. At first, a mesh convergence study was performed. It was shown that the resolution of the radial clearances in particular had a significant influence on the predicted leakages and the volumetric efficiency. The leakage was further investigated concerning the dependence on rotational speed and delivery pressure. In the next step, multiphase flows were considered. In a first setup, vapor cavitation was analyzed and the influence of the alignment of the suction ports on its onset was derived. In a second setup, the influence of different inlet volume fractions of free air was evaluated. The employed multiphase modeling approach was presented and a sensitivity analysis on modeling parameters was performed. Overall, it was shown that free air in the suction ports changed the pumping characteristic of the vane pump significantly. Pressure and flow ripple increased, and the volumetric efficiency and the mean power demand decreased significantly with an increasing inlet volume fraction.
Analysis of Synchronization Stability for Multi VSCs Parallel-Connected to Weak Grids by Improved Net Damping Criterion
Authors: Wang Dong , Zhang Xiaojie , Yang Lei , Huang Yunhui , Huang Wei , Wu Chen , Li Shengnan
Published: June 2020

Recent studies show that the loss of stability for a voltage-source converter (VSC) in weak-grid connection is largely related to its synchronization unit, i.e., the phase-locked loop (PLL). This paper studies the synchronization stability of a system comprised by two VSCs in parallel connection to a weak grid. A reduced transfer function based small-signal model, which can allow for the interactions between PLL and converter outer power controls, is first proposed. Then, an improved net damping criterion is used to analyze the damping and stability characters of such system under various operating conditions and different controller configurations. Compared to the conventional net damping criterion, the used criterion has wider applicability in terms of stability judgment. Case studies show that the studied system tends to be unstable at weak-grid or heavy-loading conditions. The instability can be in the form of oscillations or monotonic divergence, in which, the latter is more likely to occur for the converters without grid voltage regulation capabilities. Besides, the net damping-based sensitivity studies can provide guidance on control tuning or design for stability enhancement. Detailed model-based time domain simulations are conducted to verify the analysis results.
Long-Term Effect of Lophodermium Needle Cast on The Growth of Scots Pine and Implications for Financial Outcomes
Authors: Jansons Āris , Zeltiņš Pauls , Donis Jānis , Neimane Una
Published: June 2020

In Northern Europe, climate change may facilitate the prevalence of Scots pine, yet also promote the spread of pathogens attacking this species. A common biotic risk for Scots pine in nurseries and young stands is Lophodermium needle cast, primarily caused by Lophodermium seditiosum, which negatively affects the survival and growth of saplings. Reduced tree growth has been observed several years after damage by Lophodermium needle cast. However, for decision-making in protection or resistance breeding, an estimate of financial loss is important. Thus, the study aimed to assess the long-term influence of Lophodermium needle cast on the growth and financial value of Scots pine stands. The effect of needle cast damage during the sixth growing season on growth at the age of 17 years was evaluated in a control-crossed Scots pine progeny trial, and the results indicated a significantly negative effect on the height and diameter of the trees. A significant family effect also existed on the severity of the needle cast damage. Long-term simulations indicated that severely damaged Scots pines had a reduced equivalent annual annuity (EAA) of almost 100% at the final harvest. More intensive early management to reduce stand density could partly compensate for losses caused by needle cast. A higher EAA for the most resistant group of trees regardless of the stand management scenarios suggests an economically justified potential for improved resistance. Strong negative (−0.62 to −0.70) correlations of height and survival with the proportion of severely affected trees at the family mean level implies that resistant genotypes can be selected along with improved growth in progeny trials, which are affected by needle cast.
Obesity and Morbidity Risk in the U.S. Veteran
Authors: Betancourt Jose A. , Stigler Granados Paula , Pacheco Gerardo J. , Shanmugam Ramalingam , Kruse C. Scott , Fulton Lawrence V.
Published: June 2020

The obesity epidemic in the United States has been well documented and serves as the basis for a number of health interventions across the nation. However, those who have served in the U.S. military (Veteran population) suffer from obesity in higher numbers and have an overall disproportionate poorer health status when compared to the health of the older non-Veteran population in the U.S. which may further compound their overall health risk. This study examined both the commonalities and the differences in obesity rates and the associated co-morbidities among the U.S. Veteran population, utilizing data from the 2018 Behavioral Risk Factor Surveillance System (BRFSS). These data are considered by the Centers for Disease Control and Prevention (CDC) to be the nation’s best source for health-related survey data, and the 2018 version includes 437,467 observations. Study findings show not only a significantly higher risk of obesity in the U.S. Veteran population, but also a significantly higher level (higher odds ratio) of the associated co-morbidities when compared to non-Veterans, including coronary heart disease (CHD) or angina (odds ratio (OR) = 2.63); stroke (OR = 1.86); skin cancer (OR = 2.18); other cancers (OR = 1.73); chronic obstructive pulmonary disease (COPD) (OR = 1.52), emphysema, or chronic bronchitis; arthritis (OR = 1.52), rheumatoid arthritis, gout, lupus, or fibromyalgia; depressive disorders (OR = 0.84), and diabetes (OR = 1.61) at the 0.95 confidence interval level.
Chemical Characterization of Seasonal PM2.5 Samples and Their Cytotoxicity in Human Lung Epithelial Cells (A549)
Authors: Di Ao , Wu Yun , Chen Mindong , Nie Dongyang , Ge Xinlei
Published: June 2020

In order to study the toxicity of fine particulate matter (PM2.5) sourced from different seasons on human health, we collected PM2.5 samples quarterly from March 2016 to February 2017 in Nanjing, China. The component analysis results showed that high proportions of water-soluble organic carbon (WSOC), SO42−, Ca2+ and Mg2+ were found in the summer samples, while high proportions of NO3−, NH4+ and heavy metals were observed in the spring and winter samples. Then human lung epithelial cells (A549) were exposed to the PM2.5 samples. The toxicological results indicated that reactive oxygen species (ROS) production in the spring and winter samples was higher than that in the summer and fall samples, which was related to the contribution of some heavy metals and inorganic ions (e.g., Pb and NO3−). However, the apoptosis rates of the cells showed the opposite seasonal changes as what the ROS did, which might be caused by the higher WSOC content in the summer. In addition, regression analysis also showed the importance of the PM2.5 components in ROS production and apoptosis. Particularly, Zn had the strongest correlation with ROS production (R = 0.863) and cell apoptosis (R = 0.675); thus, the specific toxicity of Zn in PM2.5 deserves further investigation. Our results could be beneficial for assessing the health risks and controlling the toxic components of PM2.5 in Nanjing.
Resilience Scale Psychometric Study. Adaptation to the Spanish Population in Nursing Students
Authors: Tur Porcar Ana M. , Cuartero Monteagudo Noemí , Gea-Caballero Vicente , Juárez-Vela Raúl
Published: June 2020

Nursing students and professionals are exposed to highly stressful clinical situations. However, when confronted with stress, which is exacerbated by academic and professional situations, there is a great disparity between those who do not know how to respond suitably to the demands from patients or teachers due to a lack of competence and personal resistance, and those who are more resilient and develop a greater range of strengths. This research aims to analyse the validity and psychometric characteristics of a questionnaire on resilience adapted to Spanish nursing bachelor’s degree students. The participants were 434 undergraduate nursing students from the province of Valencia (Spain) between 17 and 54 years of age (Mean, M = 21; Standard Deviation, SD = 0.320), 104 of whom were men (24%) and 330 women (76%). A cross-sectional group evaluation was carried out in the university itself, adhering to the ethical standards of the Declaration of Helsinki. Based on the descriptive, factorial, exploratory and confirmatory analyses, it was possible to confirm the suitability of the questionnaire and its adaptation to nursing students. The model is thus suitable for evaluating the population under study. Furthermore, there are statistically significant differences depending on age and gender. The results show that the questionnaire analysed is suited to evaluating resilience among Spanish nursing students, thereby justifying the adaptation of a scale of this nature to foster resilience among nursing students and nurses in professional life, who are exposed to critical situations with patients’ suffering, deterioration or death. Our study highlights important practical implications: Spanish nursing studies involve theory and practice, but students and nurses in professional life have to confront critical situations of patients’ suffering, deterioration, or death. These situations cause stress and feelings of impotence that may lead to chronic stress and even suicidal thoughts.
Implant Placement in Patients under Treatment with Rivaroxaban: A Retrospective Clinical Study
Authors: Galletti Guido , Alfonsi Fortunato , Raffaele Angelo , Valente Nicola Alberto , Chatelain Sibylle , Kolerman Roni , Cinquini Chiara , Romeggio Stefano , Iezzi Giovanna , Barone Antonio
Published: June 2020

The management of patients under treatment with Direct Oral Anticoagulants (DOACs) has led clinicians to deal with two clinical issues, such as the hemorrhagic risk in case of non-interruption or the risk of thromboembolism in case of suspension of the treatment. The primary aim of this retrospective study was to evaluate the incidence of perioperative bleeding events and healing complications in patients who were under treatment with Rivaroxaban and who received dental implants and immediate prosthetic restoration. Patients treated with Rivaroxaban (Xarelto 20 mg daily) and who needed implant rehabilitation were selected. Four to six implants were placed in mandibular healed sites or fresh extraction sockets. All patients, in agreement with their physicians, interrupted the medication for 24 h and received implants and immediate restorations. Twelve patients and 57 implants were analyzed in the study. No major postoperative bleeding events were reported. Three patients (25%) presented slight immediate postoperative bleeding controlled with compression only. The implant and prosthetic survival rate were both 100% after 1 year. Within the limitations of this study, multiple implant placement with an immediate loading can be performed without any significant complication with a 24 h discontinuation of Rivaroxaban, in conjunction with the patient’s physician.
How Does the Family Influence the Physical Condition and Health of Children in a Rural Environment?
Authors: Martínez-Martínez Jesús , González-Víllora Sixto , Valenciano Valcárcel Javier , Pastor-Vicedo Juan Carlos
Published: June 2020

The aim of this cross-sectional study was to assess physical conditions related to health status and establish relationships with influencing factors such as family structure, educational level, and parental professional occupation in the infant stage of three to five years in a rural setting. The sample included 205 children between 3 and 5 years of age from rural areas (<10,000 inhabitants) from the region of Castilla-La Mancha (Spain). Fitness level was measured using the PREFIT battery; influencing factors were assessed with a family information questionnaire. The results showed significant differences in all the analyzed variables of physical condition and between genders at each of the educational levels except for body mass index. Boys performed better than girls on cardio-respiratory fitness tests, muscle strength in both hands, speed-agility, and longitudinal jump tests for boys aged three, while girls performed the test better at four years. The type of family structure was not correlated with any of the variables of physical condition; a lower level of education of the father and mother and the professional occupation of the mother were correlated with a higher body mass index. As a main conclusion, physical condition related to health seems to be affected by influencing factors such as educational level and family professional occupation, especially of the mother, but the type of family structure does not have as much influence. There are few studies in children from three to five years of age in exclusively rural areas, so the data in this study provides relevant and innovative information, while opening research to cater to this population group.
Facial Skin Temperature and Discomfort When Wearing Protective Face Masks: Thermal Infrared Imaging Evaluation and Hands Moving the Mask
Authors: Scarano Antonio , Inchingolo Francesco , Lorusso Felice
Published: June 2020

Individual respiratory protective devices and face masks represent critical tools in protecting health care workers in hospitals and clinics, and play a central role in decreasing the spread of the high-risk pandemic infection of 2019, coronavirus disease (COVID-19). The aim of the present study was to compare the facial skin temperature and the heat flow when wearing medical surgical masks to the same factors when wearing N95 respirators. A total of 20 subjects were recruited and during the evaluation, each subject was invited to wear a surgical mask or respirator for 1 h. The next day in the morning at the same hour, the same subject wore a N95 mask for 1 h with the same protocol. Infrared thermal evaluation was performed to measure the facial temperature of the perioral region and the perception ratings related to the humidity, heat, breathing difficulty, and discomfort were recorded. A significant difference in heat flow and perioral region temperature was recorded between the surgical mask and the N95 respirator (p < 0.05). A statistically significant difference in humidity, heat, breathing difficulty, and discomfort was present between the groups. The study results suggest that N95 respirators are able to induce an increased facial skin temperature, greater discomfort and lower wearing adherence when compared to the medical surgical masks.