bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Test and Prediction Model of Soil Thermal Conductivity in Permafrost Regions
Authors: Cui Fu-Qing , Liu Zhi-Yun , Chen Jian-Bing , Dong Yuan-Hong , Jin Long , Peng Hui
Published: April 2020

Soil thermal conductivity is a dominant parameter of an unsteady heat-transfer process, which further influences the stability and sustainability of engineering applications in permafrost regions. In this work, a laboratory test for massive specimens is performed to reveal the distribution characteristics and the parameter-influencing mechanisms of soil thermal conductivity along the Qinghai–Tibet Engineering Corridor (QTEC). Based on the measurement data of 638 unfrozen and 860 frozen soil specimens, binary fitting, radial basis function (RBF) neural network and ternary fitting (for frozen soils) prediction models of soil thermal conductivity have been developed and compared. The results demonstrate that, (1) particle size and intrinsic heat-conducting capacity of the soil skeleton have a significant influence on the soil thermal conductivity, and the typical specimens in the QTEC can be classified as three clusters according to their thermal conductivity probability distribution and water-holding capacity; (2) dry density as well as water content sometimes does not have a strong positive correlation with thermal conductivity of natural soil samples, especially for multiple soil types and complex compositions; (3) both the RBF neural network method and ternary fitting method have favorable prediction accuracy and a wide application range. The maximum determination coefficient (R2) and quantitative proportion of relative error within ±10% ( P ± 10 % ) of each prediction model reaches up to 0.82, 0.88, 81.4% and 74.5%, respectively. Furthermore, because the ternary fitting method can only be used for frozen soils, the RBF neural network method is considered the optimal approach among all three prediction methods. This study can contribute to the construction and maintenance of engineering applications in permafrost regions.
Comparative Analysis of 5G Mobile Communication Network Architectures
Authors: Lee Woosik , Suh Eun Suk , Kwak Woo Young , Han Hoon
Published: April 2020

Mobile communication technology is evolving from 4G to 5G. Compared to previous generations, 5G has the capability to implement latency-critical services, such as autonomous driving, real-time AI on handheld devices and remote drone control. Multi-access Edge Computing is one of the key technologies of 5G in guaranteeing ultra-low latency aimed to support latency critical services by distributing centralized computing resources to networks edges closer to users. However, due to its high granularity of computing resources, Multi-access Edge Computing has an architectural vulnerability in that it can lead to the overloading of regional computing resources, a phenomenon called regional traffic explosion. This paper proposes an improved communication architecture called Hybrid Cloud Computing, which combines the advantages of both Centralized Cloud Computing and Multi-access Edge Computing. The performance of the proposed network architecture is evaluated by utilizing a discrete-event simulation model. Finally, the results, advantages, and disadvantages of various network architectures are discussed.
One-Step Fabrication of Protonic Ceramic Fuel Cells Using a Convenient Tape Calendering Method
Authors: Tarutin Artem , Danilov Nikolay , Lyagaeva Julia , Medvedev Dmitry
Published: April 2020

The present paper reports the preparation of multilayer protonic ceramic fuel cells (PCFCs) using a single sintering step. The success of this fabrication approach is due to two main factors: the rational choice of chemically and mechanically compatible components, as well as the selection of a convenient preparation (tape calendering) method. The PCFCs prepared in this manner consisted of a 30 µm BaCe0.5Zr0.3Dy0.2O3–δ (BCZD) electrolyte layer, a 500 μm Ni–BCZD supporting electrode layer and a 20 μm functional Pr1.9Ba0.1NiO4+δ (PBN)–BCZD cathode layer. These layers were jointly co-fired at 1350 °C for 5 h to reach excellent gas-tightness of the electrolyte and porous structures for the supported and functional electrodes. The adequate fuel cell performance of this PCFC design (400 mW cm−2 at 600 °C) demonstrates that the tape calendering method compares well with such conventional laboratory PCFC preparation techniques such as co-pressing and tape-casting.
Designing Audio Equalization Filters by Deep Neural Networks
Authors: Pepe Giovanni , Gabrielli Leonardo , Squartini Stefano , Cattani Luca
Published: April 2020

Audio equalization is an active research topic aiming at improving the audio quality of a loudspeaker system by correcting the overall frequency response using linear filters. The estimation of their coefficients is not an easy task, especially in binaural and multipoint scenarios, due to the contribution of multiple impulse responses to each listening point. This paper presents a deep learning approach for tuning filter coefficients employing three different neural networks architectures—the Multilayer Perceptron, the Convolutional Neural Network, and the Convolutional Autoencoder. Suitable loss functions are proposed for each architecture, and are formulated in terms of spectral Euclidean distance. The experiments were conducted in the automotive scenario, considering several loudspeakers and microphones. The obtained results show that deep learning techniques give superior performance compared to baseline methods, achieving almost flat magnitude frequency response.
An ANN-Based Approach for Real-Time Scheduling in Cloud Manufacturing
Authors: Chen Shengkai , Fang Shuliang , Tang Renzhong
Published: April 2020

The cloud manufacturing platform needs to allocate the endlessly emerging tasks to the resources scattered in different places for processing. However, this real-time scheduling problem in the cloud environment is more complicated than that in a traditional workshop because constraints, such as type matching, task precedence, resource occupation, and logistics duration, need to be met, and the internal manufacturing plan of providers must also be considered. Since the platform aggregates massive manufacturing resources to serve large-scale manufacturing tasks, the space of feasible solutions is huge, resulting in many conventional search algorithms no longer being applicable. In this paper, we considered resource allocation as the key procedure for real-time scheduling, and an ANN (Artificial Neural Network) based model is established to predict the task completion status for resource allocation among candidates. The trained ANN model has high prediction accuracy, and the ANN-based scheduling approach performs better than the preferred method in terms of the optimization objectives, including total cost, service satisfaction, and make-span. In addition, the proposed approach has potential in the application for smart manufacturing or Industry 4.0 because of its high response performance and good scalability.
Development of an Eco-Friendly Head Impact Protection Device
Authors: Varela Miguel M. , Fernandes Fábio A.O. , Alves de Sousa Ricardo J.
Published: April 2020

Nowadays, the number of people practising contact sports has increased. In many of them, using head protective equipment is not mandatory, even if the use of headbands could increase the level of safety regarding several types of traumatic brain injuries. Many commercial solutions are currently available, based on plastic-based foams providing a decent level of protection and comfort to the user. This work introduces the use of agglomerated cork as an eco-friendly alternative to synthetic foams but at least keeping safety levels. Cork is a natural cellular material that has been showing excellent crashworthiness properties. In this study, cork agglomerate density is carefully chosen to be incorporated into a protective headband. Results are compared against three other commercial headbands. For each one, the risk of brain injury was analysed for different injury thresholds and impact energies. The results clearly demonstrate that the cork-based apparel may provide comparable, and in some cases, better performances, outlasting the commercial ones.
Smoothing and Differentiation of Kinematic Data Using Functional Data Analysis Approach: An Application of Automatic and Subjective Methods
Authors: Zin Muhammad Athif Mat , Rambely Azmin Sham , Ariff Noratiqah Mohd , Ariffin Muhammad Shahimi
Published: April 2020

Smoothing is one of the fundamental procedures in functional data analysis (FDA). The smoothing parameter λ influences data smoothness and fitting, which is governed by selecting automatic methods, namely, cross-validation (CV) and generalized cross-validation (GCV) or subjective assessment. However, previous biomechanics research has only applied subjective assessment in choosing optimal λ without using any automatic methods beforehand. None of that research demonstrated how the subjective assessment was made. Thus, the goal of this research was to apply the FDA method to smoothing and differentiating kinematic data, specifically right hip flexion/extension (F/E) angle during the American kettlebell swing (AKS) and determine the optimal λ . CV and GCV were applied prior to the subjective assessment with various values of λ together with cubic and quintic spline (B-spline) bases using the FDA approach. The selection of optimal λ was based on smoothed and well-fitted first and second derivatives. The chosen optimal λ was 1 × 10 − 12 with a quintic spline (B-spline) basis and penalized fourth-order derivative. Quintic spline is a better smoothing and differentiation method compared to cubic spline, as it does not produce zero acceleration at endpoints. CV and GCV did not give optimal λ , forcing subjective assessment to be employed instead.
Measurement of the Permissible Range of Consistency between Visual and Tactile Presentations of Line Grating Textures
Authors: Yamaguchi Shun , Kaneko Seitaro , Kajimoto Hiroyuki
Published: April 2020

The use of real textures is the optimal way to present realistic textures in a VR (Virtual Reality) experience. However, a system may require the presentation of numerous objects in a VR scene, making the use of real objects impractical. One way to address this issue is to present visual and tactile texture information simultaneously such that multiple different visual textures are associated with one tactile sensation. This tactile sensation must differ from the visual information only to the extent that the user still perceives the stimuli as consistent. This study examines the consistency required for the simultaneous presentation of visual and tactile sensations for the purpose of reducing the number of necessary real textures in future VR systems. An experiment was conducted using one-dimensional textures (i.e., line gratings), in which participants were asked whether the presented visual texture was finer or coarser than the tactile texture. The results suggest that the relative size of the “permissible range” (the range over which the difference between the visual and tactile sensation is not recognized) is correlated with the spatial period of the real texture.
Adaptive Leader-Follower Formation Control of under-Actuated Surface Vessels with Model Uncertainties and Input Constraints
Authors: Riahifard Alireza , Hosseini Rostami Seyyed Mohammad , Wang Jin , Kim Hye-Jin
Published: April 2020

The authors wish to make the following corrections to this paper [...]
Determination of Trolox Equivalent Antioxidant Capacity in Berries Using Amperometric Tyrosinase Biosensor Based on Multi-Walled Carbon Nanotubes
Authors: Frangu Arbër , Ashrafi Amir M. , Sýs Milan , Arbneshi Tahir , Metelka Radovan , Adam Vojtěch , Vlček Milan , Richtera Lukáš
Published: April 2020

In this contribution, Trolox equivalent antioxidant capacity (TEAC) was determined in various berries using carbon paste tyrosinase biosensor with multi-walled carbon nanotubes (MWCNTs), coated with Nafion® layer. Electrochemical behaviour of the biosensor and influence of MWCNTs on carbon paste surface were studied with respect to the sensitive amperometric detection of total content of phenolic compounds in berries, expressed as concentration equivalent of Trolox. After optimization of key instrumental and electroanalytical parameters, the biosensor was used for determination of TEAC in blackberries, blueberries, cranberries, raspberries and strawberries by method of multiple standard additions. Electrochemical TEAC assays corresponded well with results obtained by spectrophotometric 1,1-diphenyl-2-picrylhydrazyl radical method, known as DPPH assay. Obtained values were compared with those listed in the National Nutrient Database for additional antioxidant capacity assays as well.
Design and Analysis of Heavily Doped n+ Pocket Asymmetrical Junction-Less Double Gate MOSFET for Biomedical Applications
Authors: Mendiratta Namrata , Tripathi Suman Lata , Padmanaban Sanjeevikumar , Hossain Eklas
Published: April 2020

The Complementary Metal-Oxide Semiconductor (CMOS) technology has evolved to a great extent and is being used for different applications like environmental, biomedical, radiofrequency and switching, etc. Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) based biosensors are used for detecting various enzymes, molecules, pathogens and antigens efficiently with a less time-consuming process involved in comparison to other options. Early-stage detection of disease is easily possible using Field-Effect Transistor (FET) based biosensors. In this paper, a steep subthreshold heavily doped n+ pocket asymmetrical junctionless MOSFET is designed for biomedical applications by introducing a nanogap cavity region at the gate-oxide interface. The nanogap cavity region is introduced in such a manner that it is sensitive to variation in biomolecules present in the cavity region. The analysis is based on dielectric modulation or changes due to variation in the bio-molecules present in the environment or the human body. The analysis of proposed asymmetrical junctionless MOSFET with nanogap cavity region is carried out with different dielectric materials and variations in cavity length and height inside the gate–oxide interface. Further, this device also showed significant variation for changes in different introduced charged particles or region materials, as simulated through a 2D visual Technology Computer-Aided Design (TCAD) device simulator.
Lab-Scale Optimization of Aurantiochytrium sp. Culture Medium for Improved Growth and DHA Production
Authors: Trovão Mafalda , Pereira Hugo , Costa Margarida , Machado Adriana , Barros Ana , Soares Maria , Carvalho Bernardo , Silva Joana , Varela João , Silva Joana
Published: April 2020

Thraustochytrids have gained increasing relevance over the last decades, due to their fast growth and outstanding capacity to accumulate polyunsaturated fatty acids (PUFAs), particularly docosahexaenoic acid (DHA). In this context, the present work aimed to optimize the growth performance and DHA yields by improving the culture medium of Aurantiochytrium sp. AF0043. Accordingly, two distinct culture media were optimized: (i) an inorganic optimized medium (IOM), containing only monosodium glutamate and glucose as nitrogen and carbon sources, respectively; and (ii) an organic and sustainable waste-based optimized medium (WOM), containing corn steep powder and glycerol, added in fed-batch mode, as nitrogen and carbon sources, respectively. Overall, the lab-scale optimization allowed to increase the biomass yield 1.5-fold and enhance DHA content 1.7-fold using IOM. Moreover, WOM enabled a 2-fold increase in biomass yield and a significant improvement in lipid contents, from 22.78% to 31.14%. However, DHA content was enhanced almost 3-fold, from an initial content of 10.12% to 29.66% of total fatty acids contained in the biomass. Therefore, these results strongly suggest, not only that the production pipeline was significantly improved but also confirmed the potential use of Aurantiochytrium sp. AF0043 as a source of DHA.
End-to-End Classification Network for Ice Sheet Subsurface Targets in Radar Imagery
Authors: Cai Yiheng , Hu Shaobin , Lang Shinan , Guo Yajun , Liu Jiaqi
Published: April 2020

Sea level rise, caused by the accelerated melting of glaciers in Greenland and Antarctica in recent decades, has become a major concern in the scientific, environmental, and political arenas. A comprehensive study of the properties of the ice subsurface targets is particularly important for a reliable analysis of their future evolution. Newer deep learning techniques greatly outperform the traditional techniques based on hand-crafted feature engineering. Therefore, we propose an efficient end-to-end network for the automatic classification of ice sheet subsurface targets in radar imagery. Our network uses bilateral filtering to reduce noise and consists of ResNet module, improved Atrous Spatial Pyramid Pooling (ASPP) module, and decoder module. With radar images provided by the Center of Remote Sensing of Ice Sheets (CReSIS) from 2009 to 2011 as our training and testing data, experimental results confirm the robustness and effectiveness of the proposed network in radargram.
Silver Nanoparticles Ecofriendly Synthesized by Achyranthes aspera and Scoparia dulcis Leaf Broth as an Effective Fungicide
Authors: Le Ngoc Thuy Trang , Nguyen Dai Hai , Nguyen Ngoc Hoi , Ching Yern Chee , Pham Nguyen Dong Yen , Ngo Cuong Quoc , Nhat Hang Nguyen Thi , Hoang Thi Thai Thanh
Published: April 2020

This study describes an inexpensive, simple and green method to form silver nanoparticles from different leaf extracts of Achyranthes aspera and Scoparia dulcis plants. The silver nitrate is reduced by Achyranthes aspera and Scoparia dulcis leaf extracts respectively to generate two silver nanoparticle types symbolized as AA.AgNPs and SD.AgNPs. The optical absorption, size and morphology of silver nanoparticles are significantly impacted by extract types. The ultraviolet visible spectrum of AA.AgNPs shows a 433-nm peak being more broadened than that of SD.AgNPs. The Fourier infrared transform spectra of two of these silver nanoparticles revealed that their surface is modified by organic constituents from extracts, and thus they are stabilized in solution without any additional reaction. Images from transmission electron microscopy and scanning electron microscope indicate that AA.AgNPs are in clusters with the size of 8–52 nm almost possessing oval shape, while SD.AgNPs are smaller size of 5-45 nm separated well in diversified shapes (spherical, triangle, quadrilateral and hexagonal). Moreover, both AA.AgNPs and SD.AgNPs exhibit the highly antifungal effect against Aspergillus niger, Aspergillus flavus and the most strong impact on Fusarium oxysporum. For these obtained results, two new silver nanoparticles are promising fungicides for various applications of medical and agricultural fields.
In-Orbit Results and Attitude Analysis of the SNUGLITE Cube-Satellite
Authors: Kim O-Jong , Shim Hanjoon , Yu Sunkyoung , Bae Yonghwan , Kee Changdon , Kim Hakdu , Lee Jungchul , Han Jinhee , Han Sanghyuck , Choi Yeonju
Published: April 2020

SNUGLITE (Seoul National University Global navigation satellite system Laboratory satellITE) is a two-unit cube satellite (CubeSat) with dimensions 10 × 10 × 23 cm that requires an attitude system for missions and ground station telecommunication. A linear-quadratic-Gaussian-based optimal attitude system for the CubeSat platform has been developed using low-cost sensors, with the in-orbit verification of the attitude system being is one of main study objectives. Since launch, the SNUGLITE CubeSat has continuously broadcast in-orbit status information. In this study, a methodology for the analysis of in-orbit attitude estimation results using received data is presented, and this was achieved by comparing two sun-pointing vectors, i.e., the sun-pointing vector calculated using estimated attitude with the positions of the sun and the satellite and the reference vector generated by the power levels of the solar panels. Because the satellite position was required for the attitude analysis, the verification of the performance of the own-developed on-board Global Positioning System (GPS) receiver is also briefly described. Analyses indicate that the attitude estimation of the SNUGLITE CubeSat has achieved an in-orbit real-time pointing accuracy with a root mean square of 6.1°.
Fabric Defect Detection System Using Stacked Convolutional Denoising Auto-Encoders Trained with Synthetic Defect Data
Authors: Han Young-Joo , Yu Ha-Jin
Published: April 2020

As defect detection using machine vision is diversifying and expanding, approaches using deep learning are increasing. Recently, there have been much research for detecting and classifying defects using image segmentation, image detection, and image classification. These methods are effective but require a large number of actual defect data. However, it is very difficult to get a large amount of actual defect data in industrial areas. To overcome this problem, we propose a method for defect detection using stacked convolutional autoencoders. The autoencoders we proposed are trained by using only non-defect data and synthetic defect data generated by using the characteristics of defect based on the knowledge of the experts. A key advantage of our approach is that actual defect data is not required, and we verified that the performance is comparable to the systems trained using real defect data.
Atmospheric Dispersion Modelling at the London VAAC: A Review of Developments since the 2010 Eyjafjallajökull Volcano Ash Cloud
Authors: Beckett Frances M. , Witham Claire S. , Leadbetter Susan J. , Crocker Ric , Webster Helen N. , Hort Matthew C. , Jones Andrew R. , Devenish Benjamin J. , Thomson David J.
Published: April 2020

It has been 10 years since the ash cloud from the eruption of Eyjafjallajökull caused unprecedented disruption to air traffic across Europe. During this event, the London Volcanic Ash Advisory Centre (VAAC) provided advice and guidance on the expected location of volcanic ash in the atmosphere using observations and the atmospheric dispersion model NAME (Numerical Atmospheric-Dispersion Modelling Environment). Rapid changes in regulatory response and procedures during the eruption introduced the requirement to also provide forecasts of ash concentrations, representing a step-change in the level of interrogation of the dispersion model output. Although disruptive, the longevity of the event afforded the scientific community the opportunity to observe and extensively study the transport and dispersion of a volcanic ash cloud. We present the development of the NAME atmospheric dispersion model and modifications to its application in the London VAAC forecasting system since 2010, based on the lessons learned. Our ability to represent both the vertical and horizontal transport of ash in the atmosphere and its removal have been improved through the introduction of new schemes to represent the sedimentation and wet deposition of volcanic ash, and updated schemes to represent deep moist atmospheric convection and parametrizations for plume spread due to unresolved mesoscale motions. A good simulation of the transport and dispersion of a volcanic ash cloud requires an accurate representation of the source and we have introduced more sophisticated approaches to representing the eruption source parameters, and their uncertainties, used to initialize NAME. Finally, upper air wind field data used by the dispersion model is now more accurate than it was in 2010. These developments have resulted in a more robust modelling system at the London VAAC, ready to provide forecasts and guidance during the next volcanic ash event.
The Role of Prenatal Melatonin in the Regulation of Childhood Obesity
Authors: Ivanov Dmitry O. , Evsyukova Inna I. , Mazzoccoli Gianluigi , Anderson George , Polyakova Victoria O. , Kvetnoy Igor M. , Carbone Annalucia , Nasyrov Ruslan A.
Published: April 2020

There is a growing awareness that pregnancy can set the foundations for an array of diverse medical conditions in the offspring, including obesity. A wide assortment of factors, including genetic, epigenetic, lifestyle, and diet can influence foetal outcomes. This article reviews the role of melatonin in the prenatal modulation of offspring obesity. A growing number of studies show that many prenatal risk factors for poor foetal metabolic outcomes, including gestational diabetes and night-shift work, are associated with a decrease in pineal gland-derived melatonin and associated alterations in the circadian rhythm. An important aspect of circadian melatonin’s effects is mediated via the circadian gene, BMAL1, including in the regulation of mitochondrial metabolism and the mitochondrial melatoninergic pathway. Alterations in the regulation of mitochondrial metabolic shifts between glycolysis and oxidative phosphorylation in immune and glia cells seem crucial to a host of human medical conditions, including in the development of obesity and the association of obesity with the risk of other medical conditions. The gut microbiome is another important hub in the pathoetiology and pathophysiology of many medical conditions, with negative consequences mediated by a decrease in the short-chain fatty acid, butyrate. The effects of butyrate are partly mediated via an increase in the melatoninergic pathway, indicating interactions of the gut microbiome with melatonin. Some of the effects of melatonin seem mediated via the alpha 7 nicotinic receptor, whilst both melatonin and butyrate may regulate obesity through the opioidergic system. Oxytocin, a recently recognized inhibitor of obesity, may also be acting via the opioidergic system. The early developmental regulation of these processes and factors by melatonin are crucial to the development of obesity and many diverse comorbidities.
Effectiveness of Glecaprevir/Pibrentasvir for Hepatitis C: Real-World Experience and Clinical Features of Retreatment Cases
Authors: Sugiura Ayumi , Joshita Satoru , Yamashita Yuki , Yamazaki Tomoo , Fujimori Naoyuki , Kimura Takefumi , Matsumoto Akihiro , Wada Shuichi , Mori Hiromitsu , Shibata Soichiro , Yoshizawa Kaname , Morita Susumu , Furuta Kiyoshi , Kamijo Atsushi , Iijima Akihiro , Kako Satoko , Maruyama Atsushi , Kobayashi Masakazu , Komatsu Michiharu , Matsumura Makiko , Miyabayashi Chiharu , Ichijo Tetsuya , Takeuchi Aki , Koike Yuriko , Gibo Yukio , Tsukadaira Toshihisa , Inada Hiroyuki , Nakano Yoshiyuki , Usuda Seiichi , Kiyosawa Kendo , Tanaka Eiji , Umemura Takeji
Published: April 2020

Glecaprevir/pibrentasvir (G/P) are direct-acting antivirals (DAAs) that achieve a high sustained virological response (SVR) rate for hepatitis C virus (HCV) infection. We investigated G/P effectiveness for HCV patients based on real-world experience and the clinical features of retreatment cases. HCV patients (n = 182) were compared for clinical features and outcomes between first treatment (n = 159) and retreatment (n = 23) G/P groups. Overall, 77 patients (42.3%) were male, the median age was 68 years, and 86/66/1/4 cases had genotype 1/2/1 + 2/3, respectively. An SVR was achieved in 97.8% (178/182) of cases by intention-to-treat analysis and 99.4% (178/179) of cases by per-protocol analysis. There were no remarkable differences between the first treatment and retreatment groups for male (42.8% vs. 39.1%, p = 0.70), median age (68 vs. 68 years, p = 0.36), prior hepatocellular carcinoma (5.8% vs. 8.7%, p = 0.59), or the fibrosis markers AST-to-platelet ratio index (APRI) (0.5 vs. 0.5, p = 0.80) and fibrosis-4 (FIB-4) index (2.2 vs. 2.6, p = 0.59). The retreatment group had a significantly more frequent history of interferon treatment (12.3% vs. 52.2%, p < 0.01) and the Y93H mutation (25.0% vs. 64.7%, p = 0.02). The number of retreatment patients who had experienced 3, 2, and 1 DAA treatment failures was 1, 3, and 19, respectively, all of whom ultimately achieved an SVR by G/P treatment. In conclusion, G/P was effective and safe for both HCV first treatment and retreatment cases despite the retreatment group having specific resistance mutations for other prior DAAs. As G/P treatment failure has been reported for P32 deletions, clinicians should consider resistance mutations during DAA selection.
Ex Vivo MRI Analytical Methods and Brain Pathology in Preterm Lambs Treated with Postnatal Dexamethasone †
Authors: Yates Nathanael J. , Feindel Kirk W. , Mehnert Andrew , Beare Richard , Quick Sophia , Blache Dominique , Pillow J. Jane , Hunt Rod W.
Published: April 2020

Postnatal glucocorticoids such as dexamethasone are effective in promoting lung development in preterm infants, but are prescribed cautiously due to concerns of neurological harm. We developed an analysis pipeline for post-mortem magnetic resonance imaging (MRI) to assess brain development and hence the neurological safety profile of postnatal dexamethasone in preterm lambs. Lambs were delivered via caesarean section at 129 days’ (d) gestation (full term ≈ 150 d) with saline-vehicle control (Saline, n = 9), low-dose tapered dexamethasone (cumulative dose = 0.75 mg/kg, n = 8), or high-dose tapered dexamethasone (cumulative dose = 2.67 mg/kg, n = 8), for seven days. Naïve fetal lambs (136 d gestation) were used as end-point maturation controls. The left-brain hemispheres were immersion-fixed in 10 % formalin (24 h), followed by paraformaldehyde (>6 months). Image sequences were empirically optimized for T1- and T2-weighted MRI and analysed using accessible methods. Spontaneous lesions detected in the white matter of the frontal cortex, temporo-parietal cortex, occipital lobe, and deep to the parahippocampal gyrus were confirmed with histology. Neither postnatal dexamethasone treatment nor gestation showed any associations with lesion incidence, frontal cortex (total, white, or grey matter) or hippocampal volume (all p > 0.05). Postnatal dexamethasone did not appear to adversely affect neurodevelopment. Our post-mortem MRI analysis pipeline is suitable for other animal models of brain development.
Examination of Correlates to Health-Related Quality of Life in Individuals with Fragile X Syndrome
Authors: Coffman Marika C. , Shaffer Rebecca C. , Schmitt Lauren M. , Dominick Kelli C. , Pedapati Ernest , Wang Angel , Berry-Kravis Elizabeth , Tartaglia Nicole , Erickson Craig A.
Published: April 2020

Health-related quality of life (HRQoL) is a multidimensional concept involving physical, psychological, social, and cognitive aspects of life. Individuals with Fragile X syndrome (FXS) experience a life-long disorder that impacts the HRQoL of the affected individual and their family. Thus, HRQoL may be an important outcome measure following intervention. However, it is yet not known whether HRQoL concerns relate to observed impairments in FXS. In the present study, we examined the nature and degree of association between HRQoL and established measures of functioning in FXS using the Parent Report for Children version of the PedsQL 4.0 Generic Core Scales and Cognitive Functioning Scale. We observed significant relationships between HRQoL a nd measures of adaptive behavior, maladaptive behaviors, and social functioning. The present study has implications for treatment outcomes for clinical trials in FXS.
Do Adolescents Use Substances to Relieve Uncomfortable Sensations? A Preliminary Examination of Negative Reinforcement among Adolescent Cannabis and Alcohol Users
Authors: May April C. , Jacobus Joanna , Stewart Jennifer L. , Simmons Alan N. , Paulus Martin P. , Tapert Susan F.
Published: April 2020

Alcohol and cannabis use are highly prevalent among adolescents and associated with negative consequences. Understanding motivations behind substance use in youth is important for informing prevention and intervention efforts. The present study aims to examine negative reinforcement principles of substance use among adolescent cannabis and alcohol users by pairing a cue reactivity paradigm with an aversive interoceptive stimulus. Adolescents (ages 15–17), classified as controls (CTL; n = 18), cannabis and/or alcohol experimenters (CAN+ALC-EXP; n = 16), or individuals meeting clinical criteria for cannabis and/or alcohol use disorder (CAN+ALC-SUD; n = 13) underwent functional magnetic resonance imaging during which they experienced an aversive interoceptive probe delivered via breathing load while simultaneously performing a cue reactivity paradigm. Participants also provided self-report ratings of how their substance use is positively or negatively reinforced. While experiencing the breathing load, CAN+ALC-SUD exhibited greater (p < 0.05) deactivation in the right amygdala, the left inferior frontal gyrus, and the left parahippocampal gyrus than CAN+ALC-EXP and CTL, who did not differ. Across all substance users, activation during the breathing load within the left parahippocampal gyrus negatively correlated with cannabis and alcohol lifetime use episodes and the left inferior frontal gyrus activity negatively correlated with lifetime alcohol use episodes. CAN+ALC-SUD reported experiencing more positive and negative reinforcement of using their substance of choice than CAN+ALC-EXP; both user groups reported higher levels of positive than negative reinforcement. Adolescents with a cannabis/alcohol use disorder demonstrate an altered response to interoceptive perturbations. However, adolescent cannabis/alcohol use does not appear to be driven by negative reinforcement, as viewing substance images did not dampen this response. Based on self-report data, the experience of positive reinforcement may be stronger for adolescents. Future studies should examine whether positive reinforcement contributes to adolescent substance use.
Brief Exposure to Infants Activates Social and Intergroup Vigilance
Authors: Cheon Bobby , Esposito Gianluca
Published: April 2020

Among humans, simply looking at infants can activate affiliative and nurturant behaviors. However, it remains unknown whether mere exposure to infants also activates other aspects of the caregiving motivational system, such as generalized defensiveness in the absence of immediate threats. Here, we demonstrate that simply viewing faces of infants (especially from the ingroup) may heighten vigilance against social threats and support for institutions that purportedly maintain security. Across two studies, participants viewed and rated one among several image types (between-subjects design): Infants, adult males, adult females, and puppies in Study 1, and infants of varying racial/ethnic groups (including one’s ingroup) and puppies in Study 2. Following exposure to one of these image types, participants completed measures of intergroup bias from a range of outgroups that differed in perceived threat, belief in a dangerous world, right-wing authoritarianism and social-political conservatism (relative to liberalism). In Study 1 (United States), stronger affiliative reactions to images of infants (but not adults or puppies) predicted stronger perceptions of a dangerous world, endorsement of right-wing authoritarianism, and support for social-political conservatism (relative to liberalism). Study 2 (Italy) revealed that exposure to images of ingroup infants (compared to outgroup infants) increased intergroup bias against outgroups that are characterized as threatening (immigrants and Arabs) and increased conservatism. These findings suggest a predisposed preparedness for social vigilance in the mere suggested presence of infants (e.g., viewing images) even in the absence of salient external threats.
Masonry Walls Retrofitted with Vertical FRP Rebars
Authors: Coccia Simona , Di Carlo Fabio , Imperatore Stefania
Published: April 2020

The out-of-plane behaviour of the walls as a consequence of an earthquake is the main vulnerability of existing masonry structures. In the case of rigid in compression not tensile resistant material, incremental dynamic analyses may be employed to evaluate the effective strength of a rocking element. When the seismic capacity of the wall is inadequate, retrofit interventions are required to assure an acceptable safety level. Conventional seismic retrofitting techniques on masonry walls influence the seismic performance of the element, which typically is modified in an out-of-plane bending behaviour. In this paper, analytical investigations are presented to investigate the possibility of a seismic retrofitting intervention able to increase the seismic strength of the wall without modifying its seismic behaviour. The analysed retrofitting technique consists in the application of composite vertical bars either in the middle section of the wall or at its external surfaces. The seismic behaviour of the retrofitted masonry wall is analytically evaluated by means of a parametric incremental dynamic analysis, carried out with an ad hoc in-house software. The effectiveness of the intervention is analysed in terms of level of seismic improvement, defined as the ratio between the seismic capacity of the reinforced and unreinforced walls.
Low-Temperature Selective Catalytic Reduction of NOx on MnO2 Octahedral Molecular Sieves (OMS-2) Doped with Co
Authors: Li Laichao , Wang Yusi , Zhang Li , Yu Yuxi , He Hanbing
Published: April 2020

To improve NO conversion and sulfur resistance of low-temperature NO-CO selective catalytic reduction (SCR), it is urgent to seek new catalyst materials. Herein, using the pre-doping method, Cox-OMS-2 with different ratios of cobalt (Co) was obtained during hydrothermal synthesis of OMS-2 molecular sieves (where x represents the doping ratio of Co, i.e., x = 0.1, 0.2, 0.3, 0.4). Co was found to very efficiently intercalate into the crystal structure of OMS-2. Co and Mn work together to promote the selective reduction reaction of NOx;; the NO conversion of Co0.3-OMS-2 was the highest among all samples. Specifically, NO conversion at 50 °C increased from 72% for undoped OMS-2 to 90% for Co0.3-OMS-2. Moreover, due to the incorporation of Co, the latter also showed better sulfur resistance.
Oxidation of Thiol Using Ionic Liquid-Supported Organotelluride as a Recyclable Catalyst
Authors: Mihoya Aya , Koguchi Shinichi , Shibuya Yuga , Mimura Minato , Oba Makoto
Published: April 2020

Organotellurium compounds are known to be useful oxidation reagents. For developing a recoverable and reusable reagent, this paper describes the use of an ionic liquid (IL) support for the organotellurium reagent and its application as a recyclable catalyst for thiol oxidation. We have successfully prepared a novel diphenyl telluride derivative 5 bearing an imidazolium hexafluorophosphate group in its structure. It is found that the IL-supported diphenyl telluride 5 efficiently catalyzed the aerobic oxidation of various thiols in [bmim]PF6 solution under photosensitized conditions to provide the corresponding disulfides in excellent yields. The product can be isolated by simple ether extraction. The IL-supported catalyst 5 remaining in the ionic liquid phase can be reused for five successive runs while retaining high catalytic activity (97% yield even in the fifth run).
Metal-Catalyzed Synthesis and Transformations of β-Haloenol Esters
Authors: Cadierno Victorio
Published: April 2020

In the last years there has been an increasing interest in the search for protocols to obtain β-haloenol esters in an efficient and selective manner as they are versatile building blocks in synthetic organic chemistry. In this article, metal-catalyzed transformations allowing the access to both acyclic and cyclic (i.e., haloenol lactones) β-haloenol esters are reviewed. Metal-catalyzed reactions in which these molecules participate as substrates are also discussed.
Wide Angle X-Ray Scattering to Study the Atomic Structure of Polymeric Fibers
Authors: Sibillano Teresa , Terzi Alberta , De Caro Liberato , Ladisa Massimo , Altamura Davide , Moliterni Anna , Lassandro Rocco , Scattarella Francesco , Siliqi Dritan , Giannini Cinzia
Published: April 2020

Natural fibrillar-like macromolecules find applications in several fields, thanks to their peculiar features, and are considered perfect building blocks for natural and artificial functional materials. Indeed, fibrous proteins (such as collagen or fibroin) are commonly used in scaffold fabrication for biomedical applications, due to the high biophysical similarity with the extracellular matrix (ECM) which stimulates tissue regeneration. In the textile industry, cellulose-based fabrics are widely used in place of cotton and viscose, which both have sustainability issues related to their fabrication. With this in mind, the structural characterization of the materials at molecular scale plays a fundamental role in gaining insight into the fiber assembly process. In this work, we report on three fibers of research interest (i.e., type I collagen, silk fibroin extracted from Bombyx mori, and cellulose) to show the power of wide-angle X-ray scattering to characterize both intra- and intermolecular parameters of fibrous polymers. The latest possibilities offered in the X-ray scattering field allow one to study fibers at solid state or dispersed in solutions as well as to perform quantitative scanning X-ray microscopy of tissues entirely or partially made by fibers.
The Influence of Urbanization and Fire Disturbance on Plant-floral Visitor Mutualistic Networks
Authors: Beal-Neves Mariana , Vogel Ely Cleusa , Westerhofer Esteves Marjorie , Blochtein Betina , Lahm Regis Alexandre , Quadros Everton L.L. , Abreu Ferreira Pedro Maria
Published: April 2020

The biodiversity loss resulting from rising levels of human impacts on ecosystems has been extensively discussed over the last years. The expansion of urban areas promotes drastic ecological changes, especially through fragmentation of natural areas. Natural grassland remnants surrounded by an urban matrix are more likely to undergo disturbance events. Since grassland ecosystems are closely related to disturbances such as fire and grazing, grassland plant communities, pollinators, and their interaction networks may be especially sensitive to urban expansion, because it promotes habitat fragmentation and modifies disturbance regimes. This work evaluated the effect of the level of urbanization and recent history of fire disturbance on grassland plants communities and plant-floral visitor mutualistic networks. We sampled plant communities and floral visitors in 12 grassland sites with different levels of urbanization and time since the last fire event. Sites with higher levels of urbanization showed higher values for plant species richness, floral visitor richness, and network asymmetry. All sampled networks were significantly nested (with one exception), asymmetric, and specialized. In addition, all networks presented more modules than expected by chance. The frequency of fire disturbance events increased with the level of urbanization. Since grassland ecosystems depend on disturbances to maintain their structure and diversity, we inferred that the history of fire disturbance was the mechanism behind the relationship between urbanization and our biological descriptors. Our findings highlight the importance of small and isolated grassland remnants as conservation assets within urban areas, and that the disturbance events that such sites are submitted to may in fact be what maintains their diversity on multiple levels.
Multidimensional Inequality in Vietnam, 2002–2012
Authors: Bui Thi Kim Thanh , Erreygers Guido
Published: April 2020

We investigate the evolution of multidimensional inequality of well-being in Vietnam in the period 2002–2012 using household survey data. Our study focuses on four crucial dimensions of human welfare: consumption, education, health and housing. We measure inequality by means of the multidimensional Atkinson index, which belongs to the Atkinson family of relative inequality indices. The choice of the values of two crucial parameters, with respect to the aversion to inequality on the one hand and the degree of substitutability between dimensions on the other hand, has a significant influence on the perceived trends of inequality. We consider different combinations of dimensions (two, three and four dimensions) and a wide variety of values of the parameters, with the aim of arriving at a robust understanding of the extent of inequality in Vietnam. Our results suggest that the level of multidimensional inequality in Vietnam has decreased, albeit that this is not the case for all combinations of the parameter values. Our study shows that looking at multidimensional rather than one-dimensional inequality leads to a richer understanding of the evolution of inequality, and indicates that it is important to be aware of the influence of value judgments on the assessment of inequality.
Development of Curriculum Design Support System Based on Word Embedding and Terminology Extraction
Authors: Woo HoSung , Kim JaMee , Lee WonGyu
Published: April 2020

The principles of computer skills have been included in primary and secondary educated since the early 2000s, and the reform of curricula is related to the development of IT. Therefore, curricula should reflect the latest technological trends and needs of society. The development of a curriculum involves the subjective judgment of a few experts or professors to extract knowledge from several similar documents. More objective extraction needs to be based on standardized terminology, and professional terminology can help build content frames for organizing curricula. The purpose of this study is to develop a smart system for extracting terms from the body of computer science (CS) knowledge and organizing knowledge areas. The extracted terms are composed of semantically similar knowledge areas, using the word2vec model. We analyzed a higher-education CS standards document and compiled a dictionary of technical terms with a hierarchical clustering structure. Based on the developed terminology dictionary, a specialized system is proposed to enhance the efficiency and objectivity of terminology extraction. The analysis of high school education courses in India and Israel using the technical term extraction system found that (1) technical terms for Software Development Fundamentals were extracted at a high rate in entry-level courses, (2) in advanced courses, the ratio of technical terms in the areas of Architecture and Organization, Programming Languages, and Software Engineering areas was high, and (3) electives that deal with advanced content had a high percentage of technical terms related to information systems.
Ergonomic Guidelines of Head-Up Display User Interface during Semi-Automated Driving
Authors: Park Kibum , Im Youngjae
Published: April 2020

Self-driving vehicles are emerging as a result of technological advances, and the range of human behavior is expanding. The collateral information on driving is increasing, and head-up displays (HUDs) can be coupled with augmented reality displays to convey additional information to drivers in innovative ways. Interference between the actual driving environment and the displayed information can cause distractions. Research is required to find out what information should be displayed and how to properly display it considering the number of information, as well as the location and arrangement of the HUD. This study aims to examine the types of HUD information presentation that enhance the driver’s intuitive understanding. The first experiment identified which information affects drivers more in self-driving conditions in terms of error rate and importance. As a result, information that the drivers consider to be of greater importance or more relevant to their safety was selected. The level of HUD information complexity was assessed in the second experiment. The independent variables were the number of symbols, location of the HUD, and arrangement of the HUD. The results showed that the number of symbols was most affected and that fewer than six should be displayed. Besides, the arrangement of contents was more intuitive when a vertical alignment was used, and the main content should be placed in the center of the windshield area. Finally, ergonomic design guidelines of the information presentation type are proposed in this study.