bluuebunny/crossref_metadata_2025 huggingface dataset:
Attack Analysis Framework for Cyber-Attack and Defense Test Platform
Authors: Qi Yulu , Jiang Rong , Jia Yan , Li Aiping
Published: September 2020

In 2012, Google first proposed the knowledge graph and applied it in the field of intelligent searching. Subsequently, knowledge graphs have been used for in-depth association analysis in different fields. In recent years, composite attacks have been discovered through association analysis in the field of cyber security. This paper proposes an attack analysis framework for cyber-attack and defense test platforms, which stores prior knowledge in a cyber security knowledge graph and attack rule base as data that can be understood by a computer, sets the time interval of analysis on the Spark framework, and then mines attack chains from massive data with spatiotemporal constraints, so as to achieve the balance between automated analysis and real-time accurate performance. The experimental results show that the analysis accuracy depends on the completeness of the cyber security knowledge graph and the precision of the detection results from security equipment. With the rational expectation about more exposure of attacks and faster upgrade of security equipment, it is necessary and meaningful to constantly improve the cyber security knowledge graph in the attack analysis framework.
Design and Implementation of an Anonymous and Secure Online Evaluation Protocol
Authors: Petrakos Nikolaos , Monachos Stefanos , Magkos Emmanouil , Kotzanikolaou Panayiotis
Published: September 2020

Course evaluations have become a common practice in most academic environments. To enhance participation, evaluations should be private and ensure a fair result. Related privacy-preserving method and technologies (e.g., anonymous credentials, Privacy Attribute-Based Credentials, and domain signatures) fail to address, at least in an obvious way, the minimal security and practicality requirements. In this paper, we propose, evaluate, and implement an efficient, anonymous evaluation protocol for academic environments. The protocol borrows ideas from well-known and efficient cryptographic approaches for anonymously submitting ballots in Internet elections for issuing one-time credentials and for anonymously broadcasting information. The proposed protocol extends the above approaches in order to provably satisfy properties such as the eligibility, privacy, fairness and verifiability of the evaluation system. Compared to the state of the art, our approach is less complex and more effective, while security properties of the proposed protocol are verified using the ProVerif cryptographic protocol verifier. A web-based implementation of the protocol has been developed and compared to other approaches and systems.
Sliding Mode Observer-Based Fault-Tolerant Secondary Control of Microgrids
Authors: Chan Joseph Chang Lun , Lee Tae H.
Published: September 2020

This paper proposes two sliding mode observer (SMO)-based fault-tolerant secondary control schemes for microgrids. The first scheme consists of a central SMO-based fault tolerant controller that uses outputs from the microgrid and estimates all states in the microgrid as well as the fault. The estimated fault is then used to reject the effect of faults on the microgrid. The second scheme is decentralised, where each distributed generator (DG) has its own SMO-based fault tolerant controller which would estimate faults affecting that DG alone, and compensate for faults in only that DG. By rejecting the effect of faults in each DG, the effect of faults on the entire microgrid can be negated. Finally, we simulate an example using both schemes, and its results verify the efficacy of the schemes for fault-tolerant secondary control of microgrids.
An Energy-Efficient Secure Forwarding Scheme for QoS Guarantee in Wireless Sensor Networks
Authors: Kim Dongwan , Yun Jaekeun , Kim Daehee
Published: September 2020

Many wireless sensor network (WSN) applications require both security and quality-of-service (QoS) to be guaranteed simultaneously. However, ensuring both security and QoS is not trivial in WSNs since security normally has bad impact on QoS. In this paper, we propose an energy-efficient secure forwarding method that minimizes energy consumption while meeting both security and QoS requirements at the same time. To accomplish this goal, we alternatively use hop-by-hop security for conserving energy through data aggregation and end-to-end security to satisfy the QoS requirement. We further analyze why hop-by-hop security with data aggregation provide better energy efficiency than end-to-end security without aggregation in detail. The simulation result shows that our proposed method outperforms other scheme in terms of energy efficiency while meeting both QoS and security.
The Impact of Pitch-To-Stall and Pitch-To-Feather Control on the Structural Loads and the Pitch Mechanism of a Wind Turbine
Authors: Samani Arash E. , De Kooning Jeroen D. M. , Kayedpour Nezmin , Singh Narender , Vandevelde Lieven
Published: September 2020

This article investigates the impact of the pitch-to-stall and pitch-to-feather control concepts on horizontal axis wind turbines (HAWTs) with different blade designs. Pitch-to-feather control is widely used to limit the power output of wind turbines in high wind speed conditions. However, stall control has not been taken forward in the industry because of the low predictability of stalled rotor aerodynamics. Despite this drawback, this article investigates the possible advantages of this control concept when compared to pitch-to-feather control with an emphasis on the control performance and its impact on the pitch mechanism and structural loads. In this study, three HAWTs with different blade designs, i.e., untwisted, stall-regulated, and pitch-regulated blades, are investigated. The control system is validated in both uniform and turbulent wind speed. The results show that pitch-to-stall control enhances the constant power control for wind turbines with untwisted and stall-regulated blade designs. Stall control alleviates the fore-aft tower loading and the blades flapwise moment of the wind turbine with stall-regulated blades in uniform winds. However, in turbulent winds, the flapwise moment increases to a certain extent as compared to pitch-to-feather control. Moreover, pitch-to-stall control considerably reduces the summed blade pitch movement, despite that it increases the risk of surface damage in the rolling bearings due to oscillating movements with a small amplitude.
Application of Optimal Energy Management Strategies for a Building Powered by PV/Battery System in Corsica Island
Authors: Ouédraogo Sarah , Faggianelli Ghjuvan Antone , Pigelet Guillaume , Duchaud Jean Laurent , Notton Gilles
Published: September 2020

The use of renewable energy sources, and in particular photovoltaics, can effectively reduce the supply of household energy from the main grid, contributing to a more sustainable community. In this paper, several energy management strategies were applied to an existing microgrid with photovoltaic (PV) production and battery storage in view to supply in electricity a building and an electric vehicle located in Ajaccio, France. The purpose was to determine how the choice of a management strategy can impact the cost and the energy share in the microgrid, using the actual electricity tariff in France as well as an over-cost due to the island situation. For some strategies, a forecasting tool was introduced and its influence on the performances of the microgrid was discussed. It appears that the performance of the strategy increased with its complexity and the use of PV forecasting.
Biorefinery of the Olive Tree—Production of Sugars from Enzymatic Hydrolysis of Olive Stone Pretreated by Alkaline Extrusion
Authors: Doménech Pablo , Duque Aleta , Higueras Isabel , Iglesias Raquel , Manzanares Paloma
Published: September 2020

This work addresses for the first time the study of olive stone (OS) biomass pretreatment by reactive extrusion technology using NaOH as the chemical agent. It is considered as a first step in the biological conversion process of the carbohydrates contained in the material into bio-based products. OS is a sub-product of the olive oil extraction process that could be used in a context of a multi-feedstock and multi-product biorefinery encompassing all residues generated around the olive oil production sector. OS biomass is pretreated in a twin-screw extruder at varying temperatures—100, 125 and 150 °C and NaOH/biomass ratios of 5% and 15% (dry weight basis), in order to estimate the effectiveness of the process to favour the release of sugars by enzymatic hydrolysis. The results show that alkaline extrusion is effective in increasing the sugar release from OS biomass compared to the raw material, being necessary to apply conditions of 15% NaOH/biomass ratio and 125 °C to attain the best carbohydrate conversion rates of 55.5% for cellulose and 57.7% for xylan in relation to the maximum theoretical achievable. Under these optimal conditions, 31.57 g of total sugars are obtained from 100 g of raw OS.
Defect Texts Mining of Secondary Device in Smart Substation with GloVe and Attention-Based Bidirectional LSTM
Authors: Chen Kai , Mahfoud Rabea Jamil , Sun Yonghui , Nan Dongliang , Wang Kaike , Haes Alhelou Hassan , Siano Pierluigi
Published: September 2020

In the process of the operation and maintenance of secondary devices in smart substation, a wealth of defect texts containing the state information of the equipment is generated. Aiming to overcome the low efficiency and low accuracy problems of artificial power text classification and mining, combined with the characteristics of power equipment defect texts, a defect texts mining method for a secondary device in a smart substation is proposed, which integrates global vectors for word representation (GloVe) method and attention-based bidirectional long short-term memory (BiLSTM-Attention) method in one model. First, the characteristics of the defect texts are analyzed and preprocessed to improve the quality of the defect texts. Then, defect texts are segmented into words, and the words are mapped to the high-dimensional feature space based on the global vectors for word representation (GloVe) model to form distributed word vectors. Finally, a text classification model based on BiLSTM-Attention was proposed to classify the defect texts of a secondary device. Precision, Recall and F1-score are selected as evaluation indicators, and compared with traditional machine learning and deep learning models. The analysis of a case study shows that the BiLSTM-Attention model has better performance and can achieve the intelligent, accurate and efficient classification of secondary device defect texts. It can assist the operation and maintenance personnel to make scientific maintenance decisions on a secondary device and improve the level of intelligent management of equipment.
A Surfactant for Enhanced Heavy Oil Recovery in Carbonate Reservoirs in High-Salinity and High-Temperature Conditions
Authors: Yang Yu-Qi , Li Liang , Wang Xiang , Fu Yue-Qun , He Xiao-Qing , Zhang Shi-Ling , Guo Ji-Xiang
Published: September 2020

In view of the difficulty of producing heavy oil from carbonate reservoirs, the surfactant SDY-1 was synthesized by homogeneous solution polymerization with a homogeneous solution polymerization technique using aliphatic amine polyoxyethylene ether (PAEn) H(OCH2CH2)nNR(CH2CH2O)nH as the raw material, epichlorohydrin as the reaction intermediate, tetrabutylammonium bromide and pentamethyldivinyltriamine as the promoters, and alkylphenol as the catalyst. Based on the analysis of reservoir fluid and rock properties, the performance of the surfactant SDY-1 was evaluated in terms of its heat resistance, its salinity tolerance, its ability to change the heavy oil–water interfacial tension and rock wettability and its oil washing efficiency. The results show that when the salinity of the formation water is 2.23 × 105 mg/L, the addition of surfactant SDY-1 can lower the super-heavy oil–water interfacial tension with an asphaltene concentration of 30.19 wt.%, which is aged at a temperature of 140 °C for 3 days, from 22.41 to 0.366 mN/m. In addition, the surfactant SDY-1 can change the contact angle of super-heavy oil–water–rock from 129.7 to 67.4° and reduce the adhesion of crude oil to the rock surface by 99.26%. The oil displacement experiment indicates that the oil washing efficiency of the surfactant SDY-1 can reach 78.7% after ageing at a temperature of 140 °C for 3 days. Compared with petroleum sulfonate flooding, the addition of SDY-1 can improve the displacement efficiency by 33.6%, and the adsorption loss is only 0.651 mg/g oil sand. It has broad application prospects for heavy oil reservoirs with high temperatures, high pressures and high asphaltene contents.
A Variable Fractional Order Fuzzy Logic Control Based MPPT Technique for Improving Energy Conversion Efficiency of Thermoelectric Power Generator
Authors: Kanagaraj N. , Rezk Hegazy , Gomaa Mohamed R.
Published: September 2020

Thermoelectric generation technology is considered to be one of the viable methods to convert waste heat energy directly into electricity. The utilization of this technology has been impeded due to low energy conversion efficiency. This paper aims to improve the energy conversion efficiency of the thermoelectric generator (TEG) model with a novel maximum power point tracking (MPPT) technique. A variable fractional order fuzzy logic controller (VFOFLC)-based MPPT technique is proposed in the present work in which the operating point of the TEG is moved quickly towards an optimal position to increase the energy harvesting. The fraction order term α, introduced in the MPPT algorithm, will expand or contract the input domain of the fuzzy logic controller (FLC to shorten the tracking time and maintain a steady-state output around the maximum power point (MPP). The performance of the proposed MPPT technique was verified with the TEG model by simulation using MATLAB /SIMULINK software. Then, the overall performance of the VFOFLC-based MPPT technique was analyzed and compared with Perturb and observe (P&O) and incremental resistance (INR)-based MPPT techniques. The obtained results confirm that the proposed MPPT technique can improve the energy conversion efficiency of the TEG by harvesting the maximum power within a shorter time and maintaining a steady-state output when compared to other techniques.
Organic Rankine Cycle Waste Heat Recovery for Passenger Hybrid Electric Vehicles
Authors: Bin Wan Ramli Wan Rashidi , Pesyridis Apostolos , Gohil Dhrumil , Alshammari Fuhaid
Published: September 2020

Electrification of road transport is a major step to solve the air quality problem and general environmental impact caused by the still widespread use of fossil fuels. At the same time, energy efficiency in the transport sector must be improved as a steppingstone towards a more sustainable future. Multiple waste heat recovery technologies are being investigated for low-temperature waste heat recovery. One of the technologies that is being considered for vehicle application is the Organic Rankine Cycle (ORC). In this paper, the potential of ORC is discussed in detail for hybrid vehicle application. The modelling and testing of multiple systems such as the hybrid vehicle, engine, and ORC waste heat recovery are performed using the computational approach in GT-SUITE software environment correlated against available engine data. It was found that the maximum cycle efficiency achieved from the ORC system was 5.4% with 2.02 kW of delivered power recovered from the waste heat available. This led to 1.0% and 1.2% of fuel economy improvement in the New European Driving Cycle (NEDC) and Worldwide Harmonised Light Vehicle Test Procedure (WLTP) driving cycle test, respectively. From the driving cycle analysis, Hybrid Electric Vehicles (HEV) and ORC are operative in a different part of the driving cycle. This is because the entire propulsion power is provided by the HEV system, resulting in less engine operation in some part of the cycle for the ORC system to function. Apart from that, a brief economic analysis of ORC Waste Heat Recovery (WHR) is also performed in this paper and a comparative analysis is carried out for different waste heat recovery technologies for hybrid vehicle application.
Inter-Hour Forecast of Solar Radiation Based on the Structural Equation Model and Ensemble Model
Authors: Zhu Tingting , Guo Yiren , Wang Cong , Ni Chao
Published: September 2020

Given the wide applications of photovoltaic (PV) power generation, the volatility in generation caused by solar radiation, which limits the capacity of the power grid, cannot be ignored. Therefore, much research has aimed to address this issue through the development of methods for accurately predicting inter-hour solar radiation and then estimating PV power. However, most forecasting methods focus on adjusting the model structure or model parameters to achieve prediction accuracy. There is little research discussing how different factors influence solar radiation and, thereby, the effectiveness of these data-driven methods regarding their prediction accuracy. In this work, the effects of several potential factors on solar radiation are estimated using correlation analysis and a structural equation model; an ensemble model is developed for predicting inter-hour solar radiation based on the interaction of those key factors. Several experiments are carried out based on an open database provided by the National Renewable Energy Laboratory. The results show that solar zenith angle, cloud cover, aerosols, and airmass have great effects on solar radiation. It is also shown that the selection of the key factor is more important than the model structure construction for predicting solar radiation precisely. The proposed ensemble model proves to outperform all sub-models and achieves about a 12% improvement over the persistent model based on the normalized root mean squared error statistic.
Prevalence of Molar–Incisor Hypomineralization and Caries in Eight-Year-Old Children in Croatia
Authors: Jurlina Davor , Uzarevic Zvonimir , Ivanisevic Zrinka , Matijevic Nikola , Matijevic Marko
Published: September 2020

The aim of this study was to detect molar–incisor hypomineralization (MIH) and caries prevalence in eight-year-old children with early mixed dentition in Eastern Croatia. There is a lack of data on MIH in Croatia. There were 729 children examined in total: 356 (48.83%) were female and 373 (51.16%) were male. The presence of MIH was found in 95 children, the prevalence of MIH was 13%, and the remaining 634 (87%) did not have any changes associated with MIH. The prevalence of caries overall in the population of examined children was 11.48%. In the group of children with MIH, the prevalence of caries was 24.14%, while in the group of children with no MIH, the prevalence of caries was 11.18%. Teeth had a Decayed, Missing, and Filled Teeth (DMFT) index of 1.2, the value of the SiC index was 1.4, and the decayed, missing, and filled teeth (dmft) index for deciduous teeth was 5.8. Children with MIH had a caries index of DMFT 2.1, and the value of the SiC index was 2.6. The index of caries for non-MIH children was DMFT 1.1 and the SiC index was 1.2. MIH prevalence in Croatia is more common in girls than in boys. MIH has a significant impact on children’s development and is a major factor in the occurrence of caries.
The Use of Fitness Influencers’ Websites by Young Adult Women: A Cross-Sectional Study
Authors: Duplaga Mariusz
Published: September 2020

The growth of the fitness industry observed in the last decade has been accompanied by the emergence of an occupation as a social media fitness influencer. The most popular are able to accumulate millions of followers. The marketing potential of fitness influencers is a subject of interest, not only for the fitness industry but also for other sectors offering products related to health, wellness, or healthy nutrition. However, the activities of fitness influencers related to the promotion of physical activity and healthy lifestyle converge with the aims of those promoting public health. The main objective of this study was to make an assessment of the determinants of regular access to fitness influencers’ sites (FIS) and their relationship with the health behaviors of young adult women. It was based on the data originating from an online survey on a representative sample of Polish women aged 18–35 years. Chi2 test, univariate, and multiply logistic regression models were used to determine the relationships between FIS and the variables related to the respondents’ characteristics of and their health behaviors. FIS were accessed by 29.3% of respondents (n = 1030) at least once a week. It was found that those living in cities with a population ranging from 20,000 to 100,000 were more likely to access FIS than those living in rural areas. Similarly, greater access was made by those in a high-income household rather than those with the lowest income, by those with inadequate rather than those with problematic health literacy and by those with high rather than low e-health literacy. The use of FIS was significantly associated with the consumptions of fruit and vegetables (OR, 95%CI: 2.77, 2.01–3.82), physical activity (1.74, 1.27–2.38), breast self-examination (1.54, 1.11–2.13), and also with the greater use of e-cigarettes (1.63, 1.09–2.43) and increased consumption of alcohol (1.37, 1.01–1.88). In conclusion, as access to Internet resources run by fitness influencers was a prevailing predictor of young adult Polish women’s health behaviors, FIS may play a potentially important role in promoting a healthy lifestyle in this population. However, it should be remembered that there are complex patterns of associations with specific behaviors, e.g., the use of e-cigarettes or alcohol consumption.
Epidemiological Study on the Dose–Effect Association between Physical Activity Volume and Body Composition of the Elderly in China
Authors: Hou Xiao , Tang Zheng-Yan , Liu Yu , Liu Yu-Jie , Liu Jing-Min
Published: September 2020

Purpose: The purpose of this study was to investigate Chinese old adults’ different body compositions in response to various levels of physical activity (PA). To the best of our knowledge, this is the first study to demonstrate the dose–response relationship between PA and body composition in old adults. Methods: 2664 participants older than 60 years (males: n = 984, females: n = 1680) were recruited for this cross-sectional health survey. PA was assessed by the short form of the International Physical Activity Questionnaire (IPAQ), and the body composition was measured by bioelectrical impedance analysis (BIA) instruments. The differences of separate body composition indices (lean body mass, LBM; bone mass, BM; and fat mass, FM) of older participants with different PA levels (below PA recommendation and over PA recommendation) were examined using the one-way analysis of variance (ANOVA). To compare the differences of three body composition indices with six different multiples of PA recommendation (0–1 REC, 1–2 REC, 2–4 REC, 4–6 REC, >6 REC), the one-way ANOVA and Turkey’s test was used for the post hoc analysis to identify the upper PA-benefit threshold in different indices of body composition. Results: The LBM and BM are significantly higher and the FM are significantly lower in old adults performing more PA volume than the WHO recommendation, compared with individuals performing less PA volume than the WHO recommendation. There were significant increases in LBM for males in “1–2 REC”, “2–4 REC”, and “>6 REC” groups, compared with the “0–1 REC” group; and there were significant increases in BM for males in “1–2 REC”, “2–4 REC”, compared with the “0–1 REC” group. The best PA volume for LBM and BM in females was the PA volume of “2–4 REC”. Additionally, whether males or females, there was no significant difference in FM between the “0–1 REC” group and other separate groups. Conclusion: The PA volume that causes best benefit for body composition of the elderly occurs at 1 to 2 times the recommended minimum PA for males, while it occurs at 2 to 4 times that recommended for females. No additional harms for old adults’ body composition occurs at six or more times the recommended minimum PA.
Frailty Status and Transport Disadvantage: Comparison of Older Adults’ Travel Behaviours between Metropolitan, Suburban, and Rural Areas of Japan
Authors: Abe Takumi , Kitamura Akihiko , Seino Satoshi , Yokoyama Yuri , Amano Hidenori , Taniguchi Yu , Nishi Mariko , Nofuji Yu , Ikeuchi Tomoko , Sugiyama Takemi , Shinkai Shoji
Published: September 2020

This study examined differences in older adults’ travel behaviours by frailty status in metropolitan, suburban, and rural areas of Japan. Data were collected from 9104 older adults (73.5 ± 5.7 years; 51% women; 19% frail) living in metropolitan (n = 5032), suburban (n = 2853), and rural areas (n = 1219) of Japan. Participants reported if they walked, cycled, drove a car, rode a car as a passenger, and used public transportation (PT) once per week or more. A standardised questionnaire was used to assess frailty status. We conducted logistic regression analysis to calculate the odds ratios of using each travel mode by frailty status stratified by locality. Relative to non-frail participants, frail participants were less likely to walk and drive a car in all three areas. Frail participants had significantly higher odds of being a car passenger in the suburban (OR = 1.73 (95% CI: 1.32, 2.25)) and rural areas (OR = 1.61 (1.10, 2.35)) but not in the metropolitan area (OR = 1.08 (0.87, 1.33)). This study found that frail older adults living in suburban and rural areas tended to rely more on cars driven by someone else, suggesting that transport disadvantage is more pronounced in suburban and rural areas than in metropolitan areas.
Gastrointestinal Symptoms and Feeding Problems and Their Associations with Dietary Interventions, Food Supplement Use, and Behavioral Characteristics in a Sample of Children and Adolescents with Autism Spectrum Disorders
Authors: Babinska Katarina , Celusakova Hana , Belica Ivan , Szapuova Zofia , Waczulikova Iveta , Nemcsicsova Dagmar , Tomova Aleksandra , Ostatnikova Daniela
Published: September 2020

Autism spectrum disorders (ASD) are characterized by impairments in social interaction, communication, and restricted, stereotyped behavior. Gastrointestinal (GI), nutritional, and feeding problems are often reported in ASD. We investigated the prevalence of GI symptoms, food selectivity, and mealtime difficulties, and their associations with dietary interventions, food supplement use, and behavioral characteristics in a sample involving 247 participants with ASD and 267 controls aged 2–18 years. Data were collected by a questionnaire. GI symptoms were observed in 88.9% of children and adolescents with ASD, more often in girls than in boys. High rates of food selectivity (69.1%) and mealtime problems (64.3%) were found. Food supplements were used by 66.7% of individuals, mainly vitamins/minerals, probiotics, and omega-3 fatty acids. In the ASD sample, 21.2% of subjects followed a diet, mostly based on gluten and milk restriction, including individuals exhibiting food selectivity. Frequency of GI symptoms, food selectivity, and mealtime problems correlated weakly, but significantly with behavioral characteristics in the ASD group, but not with food supplement use. The study demonstrated that higher frequency of GI symptoms, food selectivity, and mealtime problems are a common problem in pre-schoolers, schoolchildren, and adolescents with ASD, and together with dietary modification, they are significantly associated with ASD.
Impacts of Thresholds of Gray Value for Cone-Beam Computed Tomography 3D Reconstruction on the Accuracy of Image Matching with Optical Scan
Authors: Park Se-Won , Yoon Ra Gyoung , Lee Hyunwoo , Lee Heon-Jin , Choi Yong-Do , Lee Du-Hyeong
Published: September 2020

In cone-beam computed tomography (CBCT), the minimum threshold of the gray value of segmentation is set to convert the CBCT images to the 3D mesh reconstruction model. This study aimed to assess the accuracy of image registration of optical scans to 3D CBCT reconstructions created by different thresholds of grey values of segmentation in partial edentulous jaw conditions. CBCT of a dentate jaw was reconstructed to 3D mesh models using three different thresholds of gray value (−500, 500, and 1500), and three partially edentulous models with different numbers of remaining teeth (4, 8, and 12) were made from each 3D reconstruction model. To merge CBCT and optical scan data, optical scan images were registered to respective 3D reconstruction CBCT images using a point-based best-fit algorithm. The accuracy of image registration was assessed by measuring the positional deviation between the matched 3D images. The Kruskal–Wallis test and a post hoc Mann–Whitney U test with Bonferroni correction were used to compare the results between groups (α = 0.05). The correlations between the experimental factors were calculated using the two-way analysis of variance test. The positional deviations were lowest with the threshold of 500, followed by the threshold of 1500, and then −500. A significant interaction was found between the threshold of gray values and the number of remaining teeth on the registration accuracy. The most significant deviation was observed in the arch model with four teeth reconstructed with a gray-value threshold of −500. The threshold for the gray value of CBCT segmentation affects the accuracy of image registration of optical scans to the 3D reconstruction model of CBCT. The appropriate gray value that can visualize the anatomical structure should be set, especially when few teeth remain in the dental arch.
Solar3D: An Open-Source Tool for Estimating Solar Radiation in Urban Environments
Authors: Liang Jianming , Gong Jianhua , Xie Xiuping , Sun Jun
Published: September 2020

Solar3D is an open-source software application designed to interactively calculate solar irradiation on three-dimensional (3D) surfaces in a virtual environment constructed with combinations of 3D-city models, digital elevation models (DEMs), digital surface models (DSMs) and feature layers. The GRASS GIS r.sun solar radiation model computes solar irradiation based on two-dimensional (2D) raster maps for a given day, latitude, surface and atmospheric conditions. With the increasing availability of 3D-city models and demand for solar energy, there is an urgent need for better tools to computes solar radiation directly with 3D-city models. Solar3D extends the GRASS GIS r.sun model from 2D to 3D by feeding the model with input, including surface slope, aspect and time-resolved shading, which is derived directly from the 3D scene using computer graphics techniques. To summarize, Solar3D offers several new features that—as a whole—distinguish this novel approach from existing 3D solar irradiation tools in the following ways. (1) Solar3D can consume massive heterogeneous 3D-city models, including massive 3D-city models such as oblique airborne photogrammetry-based 3D-city models (OAP3Ds or integrated meshes); (2) Solar3D can perform near real-time pointwise calculation for duration from daily to annual; (3) Solar3D can integrate and interactively explore large-scale heterogeneous geospatial data; (4) Solar3D can calculate solar irradiation at arbitrary surface positions including on rooftops, facades and the ground.
Isolation and Characterization of the Novel Bacteriophage AXL3 against Stenotrophomonas maltophilia
Authors: McCutcheon Jaclyn G. , Lin Andrea , Dennis Jonathan J.
Published: September 2020

The rapid increase in the number of worldwide human infections caused by the extremely antibiotic resistant bacterial pathogen Stenotrophomonas maltophilia is cause for concern. An alternative treatment solution in the post-antibiotic era is phage therapy, the use of bacteriophages to selectively kill bacterial pathogens. In this study, the novel bacteriophage AXL3 (vB_SmaS-AXL_3) was isolated from soil and characterized. Host range analysis using a panel of 29 clinical S. maltophilia isolates shows successful infection of five isolates and electron microscopy indicates that AXL3 is a member of the Siphoviridae family. Complete genome sequencing and analysis reveals a 47.5 kb genome predicted to encode 65 proteins. Functionality testing suggests AXL3 is a virulent phage and results show that AXL3 uses the type IV pilus, a virulence factor on the cell surface, as its receptor across its host range. This research identifies a novel virulent phage and characterization suggests that AXL3 is a promising phage therapy candidate, with future research examining modification through genetic engineering to broaden its host range.
Advances in Molecular Dynamics Simulations and Enhanced Sampling Methods for the Study of Protein Systems
Authors: Lazim Raudah , Suh Donghyuk , Choi Sun
Published: September 2020

Molecular dynamics (MD) simulation is a rigorous theoretical tool that when used efficiently could provide reliable answers to questions pertaining to the structure-function relationship of proteins. Data collated from protein dynamics can be translated into useful statistics that can be exploited to sieve thermodynamics and kinetics crucial for the elucidation of mechanisms responsible for the modulation of biological processes such as protein-ligand binding and protein-protein association. Continuous modernization of simulation tools enables accurate prediction and characterization of the aforementioned mechanisms and these qualities are highly beneficial for the expedition of drug development when effectively applied to structure-based drug design (SBDD). In this review, current all-atom MD simulation methods, with focus on enhanced sampling techniques, utilized to examine protein structure, dynamics, and functions are discussed. This review will pivot around computer calculations of protein-ligand and protein-protein systems with applications to SBDD. In addition, we will also be highlighting limitations faced by current simulation tools as well as the improvements that have been made to ameliorate their efficiency.
Characterization of the Impact of Oncolytic Vesicular Stomatitis Virus on the Trafficking, Phenotype, and Antigen Presentation Potential of Neutrophils and Their Ability to Acquire a Non-Structural Viral Protein
Authors: Stegelmeier Ashley A. , Chan Lily , Mehrani Yeganeh , Petrik James J. , Wootton Sarah K. , Bridle Byram , Karimi Khalil
Published: September 2020

Neutrophils are innate leukocytes that mount a rapid response to invading pathogens and sites of inflammation. Although neutrophils were traditionally considered responders to bacterial infections, recent advances have demonstrated that they are interconnected with both viral infections and cancers. One promising treatment strategy for cancers is to administer an oncolytic virus to activate the immune system and directly lyse cancerous cells. A detailed characterization of how the innate immune system responds to a viral-based therapy is paramount in identifying its systemic effects. This study analyzed how administering the rhabdovirus vesicular stomatitis virus (VSV) intravenously at 1 × 109 PFU acutely influenced neutrophil populations. Bone marrow, blood, lungs, and spleen were acquired three- and 24-h after administration of VSV for analysis of neutrophils by flow cytometry. Infection with VSV caused neutrophils to rapidly egress from the bone marrow and accumulate in the lungs. A dramatic increase in immature neutrophils was observed in the lungs, as was an increase in the antigen presentation potential of these cells within the spleen. Furthermore, the potential for neutrophils to acquire viral transgene-encoded proteins was monitored using a variant of VSV that expressed enhanced green fluorescent protein (GFP). If an in vitro population of splenocytes were exposed to αCD3 and αCD28, a substantial proportion of the neutrophils would become GFP-positive. This suggested that the neutrophils could either acquire more virus-encoded antigens from infected splenocytes or were being directly infected. Five different dosing regimens were tested in mice, and it was determined that a single dose of VSV or two doses of VSV administered at a 24-h interval, resulted in a substantial proportion of neutrophils in the bone marrow becoming GFP-positive. This correlated with a decrease in the number of splenic neutrophils. Two doses administered at intervals longer than 24-h did not have these effects, suggesting that neutrophils became resistant to antigen uptake or direct infection with VSV beyond 24-h of activation. These findings implicated neutrophils as major contributors to oncolytic rhabdoviral therapies. They also provide several clear future directions for research and suggest that neutrophils should be carefully monitored during the development of all oncolytic virus-based treatment regimens.
Natural Killer Cell Dysfunction and Its Role in COVID-19
Authors: van Eeden Charmaine , Khan Lamia , Osman Mohammed S. , Cohen Tervaert Jan Willem
Published: September 2020

When facing an acute viral infection, our immune systems need to function with finite precision to enable the elimination of the pathogen, whilst protecting our bodies from immune-related damage. In many instances however this “perfect balance” is not achieved, factors such as ageing, cancer, autoimmunity and cardiovascular disease all skew the immune response which is then further distorted by viral infection. In SARS-CoV-2, although the vast majority of COVID-19 cases are mild, as of 24 August 2020, over 800,000 people have died, many from the severe inflammatory cytokine release resulting in extreme clinical manifestations such as acute respiratory distress syndrome (ARDS) and hemophagocytic lymphohistiocytosis (HLH). Severe complications are more common in elderly patients and patients with cardiovascular diseases. Natural killer (NK) cells play a critical role in modulating the immune response and in both of these patient groups, NK cell effector functions are blunted. Preliminary studies in COVID-19 patients with severe disease suggests a reduction in NK cell number and function, resulting in decreased clearance of infected and activated cells, and unchecked elevation of tissue-damaging inflammation markers. SARS-CoV-2 infection skews the immune response towards an overwhelmingly inflammatory phenotype. Restoration of NK cell effector functions has the potential to correct the delicate immune balance required to effectively overcome SARS-CoV-2 infection.
Treatment of COVID-19 Patients Post-Bariatric Surgery: Issues for Consideration
Authors: Azran Carmil , Porat Daniel , Dahan Arik , Dicker Dror
Published: September 2020

As COVID-19 has been expanding rapidly around the world, the types of patients and their backgrounds vary. The substantially altered GI anatomy/physiology after bariatric surgery presents new challenges to the field of oral drug therapy. In this report we highlight issues for consideration when treating COVID-19 patients who previously underwent bariatric surgery and provide practical tools to allow optimal care of these patients. Post-bariatric absorption/pharmacokinetic changes may warrant dose adjustment, as well as the use of liquid oral dosage forms or parenteral routes of administration, if available. Realizing the potentially altered pharmacokinetics of various drugs after bariatric surgery is essential for providing optimal pharmacological therapy and overall patient care.
Retinal Neurovascular Coupling in Diabetes
Authors: Garhöfer Gerhard , Chua Jacqueline , Tan Bingyao , Wong Damon , Schmidl Doreen , Schmetterer Leopold
Published: September 2020

Neurovascular coupling, also termed functional hyperemia, is one of the physiological key mechanisms to adjust blood flow in a neural tissue in response to functional activity. In the retina, increased neural activity, such as that induced by visual stimulation, leads to the dilatation of retinal arterioles, which is accompanied by an immediate increase in retinal and optic nerve head blood flow. According to the current scientific view, functional hyperemia ensures the adequate supply of nutrients and metabolites in response to the increased metabolic demand of the neural tissue. Although the molecular mechanisms behind neurovascular coupling are not yet fully elucidated, there is compelling evidence that this regulation is impaired in a wide variety of neurodegenerative and vascular diseases. In particular, it has been shown that the breakdown of the functional hyperemic response is an early event in patients with diabetes. There is compelling evidence that alterations in neurovascular coupling precede visible signs of diabetic retinopathy. Based on these observations, it has been hypothesized that a breakdown of functional hyperemia may contribute to the retinal complications of diabetes such as diabetic retinopathy or macular edema. The present review summarizes the current evidence of impaired neurovascular coupling in patients with diabetes. In this context, the molecular mechanisms of functional hyperemia in health and disease will be covered. Finally, we will also discuss how neurovascular coupling may in future be used to monitor disease progression or risk stratification.
Cross-Cultural Adaptation and Psychometric Properties of the Spanish Version of the Tampa Scale for Kinesiophobia for Temporomandibular Disorders
Authors: La Touche Roy , Pardo-Montero Joaquín , Cuenca-Martínez Ferran , Visscher Corine M , Paris-Alemany Alba , López-de-Uralde-Villanueva Ibai
Published: September 2020

The aim was to perform a translation, cross-cultural adaptation, and psychometric evaluation of the Spanish version of the Tampa Scale of Kinesiophobia for Temporomandibular Disorders (TSK-TMD-S). The study sample included 110 patients with TMD. We translated and cross-culturally adapted the TSK-TMD-S using standard methodology and analysed its internal consistency, test-retest reliability, construct validity, floor and ceiling effects, and discriminant validity. Confirmatory factor analysis extracted two factors and 10 items deemed essential for the scale. The TSK-TMD-S demonstrated good internal consistency (Cronbach’s α of 0.843, 0.938, and 0.885 for the entire scale, activity avoidance subscale, and somatic focus subscale, respectively; intraclass correlation coefficient, 0.81–0.9). No floor or ceiling effects were identified for this final version of the scale. The TSK-TMD-S total score showed moderate positive correlation with the craniofacial pain and disability inventory, visual analogue scale, general TSK and pain catastrophizing scale, and a moderate negative correlation with maximal mouth-opening. The receiver operating characteristic curve analysis showed that the subclassification employed for the TSK-TMD-S discriminates different kinesiophobia levels with a diagnostic accuracy between sufficient and good. The optimal cut-off point for considering kinesiophobia is 23 points. TSK-TMD-S appears to be a valid and reliable instrument for measuring kinesiophobia in patients with TMD.
Effect of Low-Pressure Plasma Treatment Parameters on Wrinkle Features
Authors: Gu Bongjun , Ko Dongwook , Jo Sungjin , Hyun Dong Choon , Oh Hyeon-Ju , Kim Jongbok
Published: September 2020

Wrinkles attract significant attention due to their ability to enhance the mechanical and optical characteristics of various optoelectronic devices. We report the effect of the plasma gas type, power, flow rate, and treatment time on the wrinkle features. When an optical adhesive was treated using a low-pressure plasma of oxygen, argon, and nitrogen, the oxygen and argon plasma generated wrinkles with the lowest and highest wavelengths, respectively. The increase in the power of the nitrogen and oxygen plasma increased the wavelengths and heights of the wrinkles; however, the increase in the power of the argon plasma increased the wavelengths and decreased the heights of the wrinkles. Argon molecules are heavier and smaller than nitrogen and oxygen molecules that have similar weights and sizes; moreover, the argon plasma comprises positive ions while the oxygen and nitrogen plasma comprise negative ions. This resulted in differences in the wrinkle features. It was concluded that a combination of different plasma gases could achieve exclusive control over either the wavelength or the height and allow a thorough analysis of the correlation between the wrinkle features and the characteristics of the electronic devices.
Pigmentation and Degradative Activity of TiO2 on Polyethylene Films Using Masterbatches Fabricated Using Variable-Frequency Ultrasound-Assisted Melt-Extrusion
Authors: Cabello-Alvarado Christian J. , Quiñones-Jurado Zoe V. , Cruz-Delgado Víctor J. , Avila-Orta Carlos A.
Published: September 2020

Ultrasound-assisted melt-extrusion method (USME) is a high-quality process used to produce polymeric compounds with an adequate homogeneous dispersion. This study evaluates white-color films of linear low-density polyethylene (LLDPE) prepared using TiO2 masterbatch obtained by ultrasound-assisted melt-extrusion at variable frequencies (USME-VF). LLDPE with three different melt-flow indices (2, 20 and 50 g/10 min) were used as the polymer matrix. The films were obtained from the dilution of masterbatches of LLDPE (melt-flow index = 2) at a concentration of 7 wt% TiO2. The morphology, pigmentation, TiO2 reactivity, and the mechanical stability of the films were assessed. The masterbatch compounds were evaluated by melt-flow index (MFI) and scanning electron microscopy (SEM). The contrast ratio, yellowness index and mechanical properties of films were also measured. The properties of whiteness and elongation at break improved in the films prepared using masterbatches with higher dispersion. Though the reactivity of the TiO2 particles increased during accelerated aging, it did not affect the elongation to rupture. The yellowness index was moderately affected in films that included TiO2 particles processed using USME-VF.
Electrochromic Performance of V2O5 Thin Films Grown by Spray Pyrolysis
Authors: Mouratis Kyriakos , Tudose Valentin , Romanitan Cosmin , Pachiu Cristina , Tutunaru Oana , Suchea Mirela , Couris Stelios , Vernardou Dimitra , Emmanouel Koudoumas
Published: September 2020

A new approach regarding the development of nanostructured V2O5 electrochromic thin films at low temperature (250 °C), using air-carrier spray deposition and ammonium metavanadate in water as precursor is presented. The obtained V2O5 films were characterized by X-ray diffraction, scanning electron microscopy and Raman spectroscopy, while their electrochromic response was studied using UV-vis absorption spectroscopy and cyclic voltammetry. The study showed that this simple, cost effective, suitable for large area deposition method can lead to V2O5 films with large active surface for electrochromic applications.
Effect Analysis of Soil Type and Silt Content on Silt-Based Foamed Concrete with Different Density
Authors: Zhang Hongbo , Qi Xiaolin , Ma Chuanyi , Wu Jianqing , Bi Yufeng , Sun Renjuan , Yu Jintao , Xie Dongdong , Song Jie
Published: September 2020

This paper investigates the influence of silt content and coarse particle content on the mechanical and physical properties of foamed concrete, including compressive and flexural strength, modulus of elasticity, water absorption, drying shrinkage, and air-void structure. Four types of silt with different coarse particle contents were obtained by soil mixing. The results showed that high density, low silt content, and high coarse particle content can provide better mechanical properties. High silt content and high coarse particle content would lead to lower drying shrinkage. Silt content was the main factor affecting the pore distribution of foamed concrete, and higher coarse particle content could optimize the air-void structure. Meanwhile, the change in air-void structure can accordingly affect the water absorption of foamed concrete. Results showed that, at the same density and silt content, higher coarse particle content can optimize the physical and mechanical properties of foamed concrete.