bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved Hybrid Routing Protocol Combining MANET and DTN
Authors: Kang Min Wook , Chung Yun Won
Published: March 2020

Hybrid protocols combining a mobile ad hoc network (MANET) and a delay tolerant network (DTN) have recently been proposed. In these works, a whole network is fragmented, and MANET is generally used for intra-fragment communication, while DTN is used for inter-fragment communication. In this paper, an improved hybrid routing protocol was proposed, wherein virtual source nodes are selected based on the delivery predictability to the destination node if routing path to the destination node is not successfully established using MANET protocol. Then, messages are delivered to the destination node from the original source node and selected virtual source nodes. Performance evaluation results show that the proposed protocol with appropriate selection of delivery predictability threshold values has a better delivery ratio than conventional protocol, at the expense of overhead ratio in the considered parameter setting.
BACombo—Bandwidth-Aware Decentralized Federated Learning
Authors: Jiang Jingyan , Hu Liang , Hu Chenghao , Liu Jiate , Wang Zhi
Published: March 2020

The emerging concern about data privacy and security has motivated the proposal of federated learning. Federated learning allows computing nodes to only synchronize the locally- trained models instead of their original data in distributed training. Conventional federated learning architecture, inherited from the parameter server design, relies on highly centralized typologies and large nodes-to-server bandwidths. However, in real-world federated learning scenarios, the network capacities between nodes are highly uniformly distributed and smaller than that in data centers. As a result, how to efficiently utilize network capacities between computing nodes is crucial for conventional federated learning. In this paper, we propose Bandwidth Aware Combo (BACombo), a model segment level decentralized federated learning, to tackle this problem. In BACombo, we propose a segmented gossip aggregation mechanism that makes full use of node-to-node bandwidth for speeding up the communication time. Besides, a bandwidth-aware worker selection model further reduces the transmission delay by greedily choosing the bandwidth-sufficient worker. The convergence guarantees are provided for BACombo. The experimental results on various datasets demonstrate that the training time is reduced by up to 18 times that of baselines without accuracy degrade.
A Review of Relay Assignment Problem in the Cooperative Wireless Sensor Networks
Authors: S. Al-kahtani Mohammed
Published: March 2020

The relay selection is a promising approach of maximizing the diversity gain achieved in the cooperative wireless sensor networks. In the cooperative networks, the proper selection of relay node is a challenging task. The proper selection of relay nodes not only improves the source–destination performance, but also maximizes the overall system performance. There are many factors involved in designing a relay selection algorithm. The different relay selection algorithms have different focus, criteria, objective, mechanism, and performance issues. In this article, several relay assignment algorithms have been analyzed to show the effectiveness of channel capacity, power allocation, coverage expansion and interference mitigation in term of proper relay selection schemes. Moreover, this paper discusses some relay selection schemes, their challenging issues, limitations, performance criteria, and mechanisms. This article also highlights the significant design issues of relay selection methods and compares them that are appropriate in the cooperative wireless sensor networks.
Towards Near-Real-Time Intrusion Detection for IoT Devices using Supervised Learning and Apache Spark
Authors: Morfino Valerio , Rampone Salvatore
Published: March 2020

In the fields of Internet of Things (IoT) infrastructures, attack and anomaly detection are rising concerns. With the increased use of IoT infrastructure in every domain, threats and attacks in these infrastructures are also growing proportionally. In this paper the performances of several machine learning algorithms in identifying cyber-attacks (namely SYN-DOS attacks) to IoT systems are compared both in terms of application performances, and in training/application times. We use supervised machine learning algorithms included in the MLlib library of Apache Spark, a fast and general engine for big data processing. We show the implementation details and the performance of those algorithms on public datasets using a training set of up to 2 million instances. We adopt a Cloud environment, emphasizing the importance of the scalability and of the elasticity of use. Results show that all the Spark algorithms used result in a very good identification accuracy (>99%). Overall, one of them, Random Forest, achieves an accuracy of 1. We also report a very short training time (23.22 sec for Decision Tree with 2 million rows). The experiments also show a very low application time (0.13 sec for over than 600,000 instances for Random Forest) using Apache Spark in the Cloud. Furthermore, the explicit model generated by Random Forest is very easy-to-implement using high- or low-level programming languages. In light of the results obtained, both in terms of computation times and identification performance, a hybrid approach for the detection of SYN-DOS cyber-attacks on IoT devices is proposed: the application of an explicit Random Forest model, implemented directly on the IoT device, along with a second level analysis (training) performed in the Cloud.
Monolithic Miniaturized Differentially-Fed Branch-Line Directional Coupler in GaAs Monolithic Technology
Authors: Gruszczynski Slawomir , Smolarz Robert , Wu Changying , Wincza Krzysztof
Published: March 2020

In this paper, a design of a miniaturized branch-line directional coupler is presented. The coupler is designed with balanced coupled-line sections, which are electrically shortened by the application of lumped capacitors. To measure the parameters of the coupler, appropriate baluns have been designed. The coupler has been designed in a GaAs PH25 UMS (united monolithic semiconductor) technology with the center frequency of 24 GHz. The measured power split equals 3 dB with the transmission/coupling imbalance not exceeding 0.6 dB. The measured return losses equal 17 dB at the center frequency, whereas the isolation reaches 17 dB. The fabricated coupler‘s size equals 630 um × 487 um, which is 0.19 of the full size of the directional coupler in the chosen technology (1191 um × 1170 um).
Implementation of Lean Management as a Tool for Decrease of Energy Consumption and CO2 Emissions in the Fast Food Restaurant
Authors: Orynycz Olga , Tucki Karol , Prystasz Miron
Published: March 2020

The manuscript presents the possibilities of using selected Lean Management tools at a fast food restaurant located at the international airport terminal in Poland. Observations in other points of the company lasting for five years, made possible fair proposals for improvement of selected elements of production and work organization. The research part presents the results of application of such tools as value stream mapping (VSM), Kaizen, and 5S. The Lean Management method, chosen after careful analysis of the work system in the facility, contributed to the increase of work efficiency. Production times were shortened. Additionally, the possibility of reducing energy consumption, and thus the reduction of CO2 emissions associated with production, achieved without interfering with product quality was demonstrated. The timetable for device work was proposed. It was selected based on the analysis of the daily number of transactions compared with energy consumption. It should be emphasized that properly selected Lean tools allow for practical increase of work efficiency, reduction of production cycle times, and a decrease of energy consumption, which, in turn, leads to the decrease of CO2 emissions. It is demonstrated that, concerning the large number of enterprises of that type, introducing appropriate changes in work organization is able to facilitate large changes in emissions on a global scale. The presented solutions were tested in practice, however, due to the nature of the place, it should be considered individually.
A New Approach for Fault Detection, Location and Diagnosis by Ultrasonic Testing
Authors: García Marquez Fausto Pedro , Gómez Muñoz Carlos Quiterio
Published: March 2020

Wind turbine blades are constantly submitted to different types of particles such as dirt, ice, etc., as well as all the different environmental parameters that affect the behaviour and efficiency of the energy generation system. These parameters can cause faults to the wind turbine blades, modifying their behaviour due, for example, to the turbulence. A new method is presented in this paper based on cross-correlations to determine the presence of delamination in the blades. The experiments were conducted in two real wind turbine blades to analyse the fault and non-fault blades using ultrasonic guided waves. Finally, the energy analysis of the signal based on wavelet transforms allowed to determine energies abrupt changes in the correlation of the signals and to locate the faults.
Pore-Fractures of Coalbed Methane Reservoir Restricted by Coal Facies in Sangjiang-Muling Coal-Bearing Basins, Northeast China
Authors: Lu Yuejian , Liu Dameng , Cai Yidong , Li Qian , Jia Qifeng
Published: March 2020

The pore-fractures network plays a key role in coalbed methane (CBM) accumulation and production, while the impacts of coal facies on the pore-fractures network performance are still poorly understood. In this work, the research on the pore-fracture occurrence of 38 collected coals from Sangjiang-Muling coal-bearing basins with multiple techniques, including mercury intrusion porosimetry (MIP), micro-organic quantitative analysis, and optic microscopy, and its variation controlling of coal face were studied. The MIP curves of 38 selected coals, indicating pore structures, were subdivided into three typical types, including type I of predominant micropores, type Ⅱ of predominant micropores and macropores with good connectivity, and type Ⅲ of predominant micropores and macropores with poor connectivity. For coal facies, three various coal facies were distinguished, including lake shore coastal wet forest swamp, the upper delta plain wet forest swamp, tidal flat wet forest swamp using Q-cluster analysis and tissue preservation index–gelification index (TPI-GI), and wood index–groundwater influence index (WI-GWI). The results show a positive relationship between tissue preservation index (TPI), wood index (WI), and mesopores (102 nm–103 nm), and a negative relationship between TPI, WI, and macropores/fractures. In addition, groundwater level fluctuations can control the development of type C and D fractures, and the frequency of type C and D fractures show an ascending trend with increasing groundwater index (GWI), which may be caused by the mineral hydration of the coal. Finally, from the perspective of the pore-fractures occurrence in CBM reservoirs, the wet forest swamp of upper delta plain is considered to be the optimization areas for Sangjiang-Muling coal-bearing basins by a comparative study of various coal facies.
Operational Risk Assessment of Electric-Gas Integrated Energy Systems Considering N-1 Accidents
Authors: Liu Hua , Li Yong , Cao Yijia , Zeng Zilong , Sidorov Denis
Published: March 2020

The reliability analysis method and risk assessment model for the traditional single network no longer meet the requirements of the risk analysis of coupled systems. This paper establishes a risk assessment system of electric-gas integrated energy system (EGIES) considering the risk security of components. According to the mathematical model of each component, the EGIES steady state analysis model considering the operation constraints is established to analyze the operation status of each component. Then the EGIES component accident set is established to simulate the accident consequences caused by the failure of each component to EGIES. Furthermore, EGIES risk assessment system is constructed to identify the vulnerability of EGIES components. Finally, the risk assessment of IEEE14-NG15 system is carried out. The simulation results verify the effectiveness of the proposed method.
Development of Neurofuzzy Architectures for Electricity Price Forecasting
Authors: Alshejari Abeer , Kodogiannis Vassilis S. , Leonidis Stavros
Published: March 2020

In 20th century, many countries have liberalized their electricity market. This power markets liberalization has directed generation companies as well as wholesale buyers to undertake a greater intense risk exposure compared to the old centralized framework. In this framework, electricity price prediction has become crucial for any market player in their decision-making process as well as strategic planning. In this study, a prototype asymmetric-based neuro-fuzzy network (AGFINN) architecture has been implemented for short-term electricity prices forecasting for ISO New England market. AGFINN framework has been designed through two different defuzzification schemes. Fuzzy clustering has been explored as an initial step for defining the fuzzy rules while an asymmetric Gaussian membership function has been utilized in the fuzzification part of the model. Results related to the minimum and maximum electricity prices for ISO New England, emphasize the superiority of the proposed model over well-established learning-based models.
Analysis of CO2 Drivers and Emissions Forecast in a Typical Industry-Oriented County: Changxing County, China
Authors: Qian Yao , Sun Lang , Qiu Quanyi , Tang Lina , Shang Xiaoqi , Lu Chengxiu
Published: March 2020

Decomposing main drivers of CO2 emissions and predicting the trend of it are the key to promoting low-carbon development for coping with climate change based on controlling GHG emissions. Here, we decomposed six drivers of CO2 emissions in Changxing County using the Logarithmic Mean Divisia Index (LMDI) method. We then constructed a model for CO2 emissions prediction based on a revised version of the Stochastic Impacts by Regression on Population, Affluence, and Technology (STIRPAT) model and used it to simulate energy-related CO2 emissions in five scenarios. Results show that: (1) From 2010 to 2017, the economic output effect was a significant, direct, dominant, and long-term driver of increasing CO2 emissions; (2) The STIRPAT model predicted that energy structure will be the decisive factor restricting total CO2 emissions from 2018 to 2035; (3) Low-carbon development in the electric power sector is the best strategy for Changxing to achieve low-carbon development. Under the tested scenarios, Changxing will likely reach peak total CO2 emissions (17.95 million tons) by 2030. Measures focused on optimizing the overall industrial structure, adjusting the internal industry sector, and optimizing the energy structure can help industry-oriented counties achieve targeted carbon reduction and control, while simultaneously achieving rapid economic development.
Optimal Design for a Shared Swap Charging System Considering the Electric Vehicle Battery Charging Rate
Authors: Zhong Lingshu , Pei Mingyang
Published: March 2020

Swap charging (SC) technology offers the possibility of swapping the batteries of electric vehicles (EVs), providing a perfect solution for achieving a long-distance freeway trip. Based on SC technology, a shared SC system (SSCS) concept is proposed to overcome the difficulties in optimal swap battery strategies for a large number of EVs with charging requests and to consider the variance in the battery charging rate simultaneously. To realize the optimal SSCS design, a binary integer programming model is developed to balance the tradeoff between the detour travel cost and the total battery recharge cost in the SSCS. The proposed method is verified with a numerical example of the freeway system in Guangdong Province, China, and can obtain an exact solution using off-the-shelf commercial solvers (e.g., Gurobi).
Separated Flow Control of Small Horizontal-Axis Wind Turbine Blades Using Dielectric Barrier Discharge Plasma Actuators
Authors: Aono Hikaru , Fukumoto Hiroaki , Abe Yoshiaki , Sato Makoto , Nonomura Taku , Fujii Kozo
Published: March 2020

The flow control over the blades of a small horizontal-axis wind turbine (HAWT) model using a dielectric barrier discharge plasma actuator (DBD-PA) was studied based on large-eddy simulations. The numerical simulations were performed with a high-resolution computational method, and the effects of the DBD-PA on the flow fields around the blades were modeled as a spatial body force distribution. The DBD-PA was installed at the leading edge of the blades, and its impacts on the flow fields and axial torque generation were discussed. The increase in the ratios of the computed, cycle-averaged axial torque reasonably agreed with that of the available experimental data. In addition, the computed results presented a maximum of 19% increase in the cycle-averaged axial torque generation by modulating the operating parameters of the DBD-PA because of the suppression of the leading edge separation when the blade’s effective angles of attack were relatively high. Thus, the suppression of the leading edge separation by flow control can lead to a delay in the breakdown of the tip vortex as a secondary effect.
Analysis of Main Factors for CH4 Emission Factor Development in Manufacturing Industries and Construction Sector
Authors: Kang Seongmin , Cho Seonghum , Roh Joonyoung , Jeon Eui-chan
Published: March 2020

This study has statistically analyzed the effect of boiler type and model year on CH4 emission factors, focusing on liquefied natural gas (LNG)—the most commonly used fuel in South Korean manufacturing combustion facilities. Samples were collected from the boilers of 39 manufacturing combustion facilities that use LNG fuel. The CH4 emission factors were developed based on 4 overhead fire-tube boilers, 14 once-through boilers, 14 vertical boilers with vertical water tubes, and 7 other boilers. This resulted in an average value of 0.11 CH4 kg/TJ, which is considerably lower than the Intergovernmental Panel on Climate Change (IPCC) 1996 guidelines(G/L) emission factor of 5 CH4 kg/TJ currently used in South Korea. In the Kruskal–Wallis test results, the significance probability was greater than 0.05 for the boiler types and ages, and there was no major difference in the average distributions, according to the boiler type or age. Therefore, according to the results of this study, the differences in the CH4 emission factors according to the boiler types and ages are not statistically large, and it was determined that there is no major difference even when the emission factors are applied to different fuel types. However, there was a major difference when the developed factors were compared to the CH4 emission factor proposed by the IPCC. Thus, there is a need to develop manufacturing combustion CH4 emission factors that reflect national characteristics.
Effect of the Refining Process on Total Hydroxytyrosol, Tyrosol, and Tocopherol Contents of Olive Oil
Authors: Lucci Paolo , Bertoz Valentina , Pacetti Deborah , Moret Sabrina , Conte Lanfranco
Published: March 2020

The impact of the olive oil refining process on major antioxidant compound levels was evaluated by means of UHPLC analysis of lampante olive oils collected at different stages of the refining procedure (degumming, chemical and physical flash neutralization, bleaching, and deodorization). For this purpose, the evolution of the tocopherol fraction was investigated by means of the UHPLC-FL method, while the influence of the refining process on the total hydrolyzed phenolic content was assessed by measuring hydroxytyrosol and tyrosol levels after acid hydrolysis of the phenolic extracts. Refining was found to have a marked effect on total hydroxytyrosol and tyrosol contents, as they are completely removed in the early steps of the refining procedure. In contrast, the variation trends of tocopherols are not always clear-cut, and significant decreases in content from 7% to 16% were only revealed during refining in four out of nine samples. In addition, five of the nine refined oils showed final tocopherol concentrations higher than 200 mg/kg, the limit imposed by international standards regarding the content of such compounds in commercial olive oils. This study supports the need for a revision of the International Olive Oil Council (IOC) standard relative to the limit established for tocopherol addition to refined oils to avoid possible legal and economic trade issues.
Effect of Sugar Substitution with Steviol Glycosides on Sensory Quality and Physicochemical Composition of Low-Sugar Apple Preserves
Authors: Pielak Marlena , Czarniecka-Skubina Ewa , Głuchowski Artur
Published: March 2020

The purpose of this study was to determine the sensory profile and consumer response, as well as physicochemical properties of low-sugar apple preserves (with or without gelling agent or acidity regulator), in which sugar was replaced with varying amounts of steviol glycosides (SGs). According to the analytical assessment and consumer tests’ results, the reduction of sugar by SGs use in the apple preserves without food additives was possible at a substitution level of 10% (0–0.05 g/100 g). Consumers’ degree of liking for sugar substitution with SGs was high, up to 40% (0.20 g/100 g) in the preserves, with the use of pectin and citric acid. Higher levels of sugar substitution with the SGs resulted in flavor and odor deterioration, such as a metallic flavor and odor, a bitter taste, an astringent oral sensation, and a sharp odor. The use of food additives (pectin, citric acid) in apple preserves, allowed the SGs substitution level to be increased. The preserves (Experiment I, II, III) with higher sensory ratings were subjected to physicochemical tests. Physical and chemical analysis of low-sugar products with sucrose substitution by SGs at the level of 10%, 30%, 40% showed their good technological quality. The results demonstrated the possibility of substituting sugar with steviol glycosides to produce energy-reduced apple preserves, with acceptable sensory quality and good physicochemical properties.
Temperature Dependence of Oxidation Kinetics of Extra Virgin Olive Oil (EVOO) and Shelf-Life Prediction
Authors: Conte Lanfranco , Milani Andrea , Calligaris Sonia , Rovellini Pierangela , Lucci Paolo , Nicoli Maria Cristina
Published: March 2020

Producers have to guarantee the extra virgin olive oil (EVOO) quality characteristics reported in the Regulation (CEE) 2568/91 throughout the product shelf-life (SL). Unfortunately, due to the development of oxidative reactions, some quality indices change during storage leading to a progressive deterioration of EVOO quality. To avoid the risk of product downgrading in the virgin oil category, the development of effective shelf-life prediction models is extremely important for the olive oil industry. In this research, the accelerated shelf-life testing (ASLT) protocol was applied to evaluate the temperature dependence of selected oxidation indexes as well as to develop a shelf-life predictive model. The evolution of conventional (peroxide value, K232, K270, polyphenols, tocopherols and hexanal) and unconventional parameters (conjugated trienes and pyropheophytin a) was monitored in bottled EVOO stored in the dark at increasing temperature (25, 40, 50 and 60 °C). Accordingly, for well-packed products with reduced oxygen in headspace, the best shelf-life index allowing the ability to predict EVOO SL turned out to be K270. In addition, pyropheophytin a (%) has been shown to be more sensitive to temperature changes than the secondary oxidation indices, thus suggesting its use as a freshness indicator for storage temperatures higher than 25 °C.
Affordability Assessment from a Static to Dynamic Concept: A Scenario-Based Assessment of Cardiovascular Medicines
Authors: Zarei Leila , Karimzadeh Iman , Moradi Najmeh , Peymani Payam , Asadi Sara , Babar Zaheer-Ud-Din
Published: March 2020

The out-of-pocket payments for prescription medications can impose a financial burden on patients from low- and middle- incomes and who suffer from chronic diseases. The present study aims at evaluating the affordability of cardiovascular disease (CVD) medication in Iran. This includes measuring affordability through World Health Organization/Health Action International (WHO/HAI) methodology. In this method, affordability is characterized as the number of days’ wages of the lowest-paid unskilled government worker. The different medication therapy scenarios are defined in mono-and combination therapy approaches. This method adds on to WHO/HAI methodology to discover new approaches to affordability assessments. The results show the differences in the medicines affordability when different approaches are used in mono-and combination therapy between 6 main sub-therapeutic groups of CVD. It indicates the medicine affordability is not a static concept and it changes dynamically between CVD therapeutic subgroups when it used alone or in combination with other medicines regarding patients’ characteristics and medical conditions. Hypertension and anti-arrhythmia therapeutic groups had the most non-affordability and hyperlipidemia had the most affordable medicines. Therefore, affordability can be considered as a dynamic concept, which not only affected by the medicine price but significantly affected by a patient’s characteristics, the number of medical conditions, and insurance coverage.
Utility of Human Papillomavirus Testing for Cervical Cancer Screening in Korea
Authors: Kim Mee-seon , Lee Eun Hee , Park Moon-il , Lee Jae Seok , Kim Kisu , Roh Mee Sook , Lee Hyoun Wook
Published: March 2020

(1) Background: Cervical cancer is one of the most common cancers in Korean women. This study was performed to discover the utility of HPV (Human Papillomavirus) testing in screening of cervical lesions and to provide the prevalence of HPV and the genotype distribution in a single center of Korea. (2) Methods: A total of 15,141 women who underwent both HPV testing and cervical cytology were enrolled in this retrospective medical record review study. (3) Results: HPV testing showed higher sensitivity than cytology for the detection of histological high-grade squamous lesions. Furthermore, the sensitivity and specificity of HPV testing varied depending on the method used. The BD Onclarity™ HPV assay had higher sensitivity (90%) than the MyHPV CHIP™ kit (all types of HPV: 82%; high-risk HPV: 76%) for high-grade squamous lesions. A combination of MyHPV CHIP™ and cytology detected 90.9% (30/33) of histological high-grade squamous lesions. A combination of BD Onclarity™ HPV assay and cytology detected 96.55% (84/87) of histological high-grade squamous lesions. In addition, HPV prevalence and genotype distribution were different depending on the HPV testing method used. (4) Conclusion: HPV testing showed higher sensitivity than cytology, but the sensitivity and specificity of HPV testing had variation depending on the method used.
Adsorption of Acid Orange Ⅱ with Two Step Modified Sepiolite: Optimization, Adsorption Performance, Kinetics, Thermodynamics and Regeneration
Authors: Yu Jian , He Wenting , Liu Bin
Published: March 2020

In this study, a two-step modification of sepiolite for adsorption enhancement was investigated. The cetyltrimethylammonium bromide (CTAB) was utilized for the organic modification process after a heat modification. To develop the optimal modification condition, adsorption of Acid Orange II onto modified sepiolite was investigated with respect to heat temperature and adsorbent dosage. The temperature of 200 °C and 100% cation exchange capacity (CEC) was deemed as the optimal condition. The impacts of operation conditions on adsorption procedure, including pH, adsorbent dosage and adsorption duration, were comprehensively discussed. The adsorption of Acid Orange II by sepiolite is in accordance with the quasi-secondary kinetic model. Moreover, the results of intraparticle diffusion indicate that the intraparticle diffusion was the dominant adsorption force in the initial adsorption period. The adsorption process was obeyed with the Langmiur adsorption model. The results from regeneration procedure suggest that the superior regeneration obtained with 0.8 mol/L NaOH concentration.
Carers’ Motivations for, and Experiences of, Participating in Suicide Research
Authors: Maple Myfanwy , Wayland Sarah , Sanford Rebecca , Spillane Ailbhe , Coker Sarah
Published: March 2020

(1) Background: First-hand accounts of lived experience of suicide remain rare in the research literature. Increasing interest in the lived experience of suicide is resulting in more opportunities for people to participate in research based on their personal experience. How individuals choose to participate in research, and their experience of doing so, are important considerations in the ethical conduct of research. (2) Methods: To understand the experience of providing care for someone who has previously attempted suicide, a cross-sectional online community survey was conducted. This survey concluded with questions regarding motivation to participate and the experience of doing so. Of the 758 individuals who participated in the survey, 545 provided open-ended text responses to questions regarding motivation and 523 did so for questions regarding the experience of participating. It is these responses that are the focus of this paper. Data were analysed thematically. (3) Results: Motivations to participate were expressed as primarily altruistic in nature, with a future focus on improving the experience of the person who had attempted suicide alongside carers to ease distress. The experience of participating was difficult yet manageable, for all but a few participants. (4) Conclusions: With the increasing interest in first-hand accounts of suicide, how individuals experience participation in research is an important focus that requires further attention.
New Perspectives Related to the Bioluminescent System in Dinoflagellates: Pyrocystis lunula, a Case Study
Authors: Fajardo Carlos , De Donato Marcos , Rodulfo Hectorina , Martinez-Rodriguez Gonzalo , Costas Benjamin , Mancera Juan Miguel , Fernandez-Acero Francisco Javier
Published: March 2020

Pyrocystis lunula is considered a model organism due to its bioluminescence capacity linked to circadian rhythms. The mechanisms underlying the bioluminescent phenomenon have been well characterized in dinoflagellates; however, there are still some aspects that remain an enigma. Such is the case of the presence and diversity of the luciferin-binding protein (LBP), as well as the synthesis process of luciferin. Here we carry out a review of the literature in relation to the molecular players responsible for bioluminescence in dinoflagellates, with particular interest in P. lunula. We also carried out a phylogenetic analysis of the conservation of protein sequence, structure and evolutionary pattern of these key players. The basic structure of the luciferase (LCF) is quite conserved among the sequences reported to date for dinoflagellate species, but not in the case of the LBP, which has proven to be more variable in terms of sequence and structure. In the case of luciferin, its synthesis has been shown to be complex process with more than one metabolic pathway involved. The glutathione S-transferase (GST) and the P630 or blue compound, seem to be involved in this process. In the same way, various hypotheses regarding the role of bioluminescence in dinoflagellates are exposed.
Solvent Dependence of the Rheological Properties in Hydrogel Magnetorheological Plastomer
Authors: Hapipi Norhiwani Mohd , Mazlan Saiful Amri , Ubaidillah U. , Abdul Aziz Siti Aishah , Ahmad Khairi Muntaz Hana , Nordin Nur Azmah , Nazmi Nurhazimah
Published: March 2020

Chemically crosslinked hydrogel magnetorheological (MR) plastomer (MRP) embedded with carbonyl iron particles (CIPs) exhibits excellent magnetic performance (MR effect) in the presence of external stimuli especially magnetic field. However, oxidation and desiccation in hydrogel MRP due to a large amount of water content as a dispersing phase would limit its usage for long-term applications, especially in industrial engineering. In this study, different solvents such as dimethyl sulfoxide (DMSO) are also used to prepare polyvinyl alcohol (PVA) hydrogel MRP. Thus, to understand the dynamic viscoelastic properties of hydrogel MRP, three different samples with different solvents: water, DMSO, and their binary mixtures (DMSO/water) were prepared and systematically carried out using the oscillatory shear. The outcomes demonstrate that the PVA hydrogel MRP prepared from precursor gel with water shows the highest MR effect of 15,544% among the PVA hydrogel MRPs. However, the samples exhibit less stability and tend to oxidise after a month. Meanwhile, the samples with binary mixtures (DMSO/water) show an acceptable MR effect of 11,024% with good stability and no CIPs oxidation. Otherwise, the sample with DMSO has the lowest MR effect of 7049% and less stable compared to the binary solvent samples. This confirms that the utilisation of DMSO as a new solvent affects the rheological properties and stability of the samples.
Combined Dendritic and Axonal Deterioration Are Responsible for Motoneuronopathy in Patient-Derived Neuronal Cell Models of Chorea-Acanthocytosis
Authors: Glaß Hannes , Neumann Patrick , Pal Arun , Reinhardt Peter , Storch Alexander , Sterneckert Jared , Hermann Andreas
Published: March 2020

Chorea acanthocytosis (ChAc), an ultra-rare devastating neurodegenerative disease, is caused by mutations in the VPS13A gene, which encodes for the protein chorein. Affected patients suffer from chorea, orofacial dyskinesia, epilepsy, parkinsonism as well as peripheral neuropathy. Although medium spinal neurons of the striatum are mainly affected, other regions are impaired as well over the course of the disease. Animal studies as well as studies on human erythrocytes suggest Lyn-kinase inhibition as valuable novel opportunity to treat ChAc. In order to investigate the peripheral neuropathy aspect, we analyzed induced pluripotent stem cell derived midbrain/hindbrain cell cultures from ChAc patients in vitro. We observed dendritic microtubule fragmentation. Furthermore, by using in vitro live cell imaging, we found a reduction in the number of lysosomes and mitochondria, shortened mitochondria, an increase in retrograde transport and hyperpolarization as measured with the fluorescent probe JC-1. Deep phenotyping pointed towards a proximal axonal deterioration as the primary axonal disease phenotype. Interestingly, pharmacological interventions, which proved to be successful in different models of ChAc, were ineffective in treating the observed axonal phenotypes. Our data suggests that treatment of this multifaceted disease might be cell type and/or neuronal subtype specific, and thus necessitates precision medicine in this ultra-rare disease.
Exploring Diverse-Ring Analogues on Combretastatin A4 (CA-4) Olefin as Microtubule-Targeting Agents
Authors: Song Ming-Yu , He Qiu-Rui , Wang Yi-Lin , Wang Hao-Ran , Jiang Tian-Cheng , Tang Jiang-Jiang , Gao Jin-Ming
Published: March 2020

Combretastatin-4 (CA-4) as a tubulin polymerization inhibitor draws extensive attentions. However, due to its weak stability of cis-olefin and poor metabolic stability, structure modifications on cis-configuration are being performed. In this work, we constructed a series of novel CA-4 analogues with linkers on olefin containing diphenylethanone, cis-locked dihydrofuran, α-substituted diphenylethanone, cyclobutane and cyclohexane on its cis-olefin. Cytotoxic activity of all analogues was measured by an SRB assay. Among them, compound 6b, a by-product in the preparation of diphenylethanone analogues, was found to be the most potent cytotoxic agents against HepG2 cells with IC50 values of less than 0.5 μM. The two isomers of 6b induced cellular apoptosis tested by Annexin V-FITC and propidium iodide (PI) double staining, arrested cells in the G2/M phase by PI staining analysis, and disrupted microtubule network by immunohistochemistry study in HepG2 cells. Moreover, 6b-(E) displayed a dose-dependent inhibition effect for tubulin assembly in in vitro tubulin polymerization assay. In addition, molecular docking studies showed that two isomers of 6b could bind efficiently at colchicine binding site of tubulin similar to CA-4.
The Cuban Propolis Component Nemorosone Inhibits Proliferation and Metastatic Properties of Human Colorectal Cancer Cells
Authors: Frión-Herrera Yahima , Gabbia Daniela , Scaffidi Michela , Zagni Letizia , Cuesta-Rubio Osmany , De Martin Sara , Carrara Maria
Published: March 2020

The majority of deaths related to colorectal cancer (CRC) are associated with the metastatic process. Alternative therapeutic strategies, such as traditional folk remedies, deserve attention for their potential ability to attenuate the invasiveness of CRC cells. The aim of this study is to investigate the biological activity of brown Cuban propolis (CP) and its main component nemorosone (NEM) and to describe the molecular mechanism(s) by which they inhibit proliferation and metastatic potential of 2 CRC cell lines, i.e., HT-29 and LoVo. Our results show that CP and NEM significantly decreased cell viability and inhibited clonogenic capacity of CRC cells in a dose and time-dependent manner, by arresting the cell cycle in the G0/G1 phase and inducing apoptosis. Furthermore, CP and NEM downregulated BCL2 gene expression and upregulated the expression of the proapoptotic genes TP53 and BAX, with a consequent activation of caspase 3/7. They also attenuated cell migration and invasion by inhibiting MMP9 activity, increasing E-cadherin and decreasing β-catenin and vimentin expression, proteins involved in the epithelial–mesenchymal transition (EMT). In conclusion NEM, besides displaying antiproliferative activity on CRC cells, is able to decrease their metastatic potential by modulating EMT-related molecules. These finding provide new insight about the mechanism(s) of the antitumoral properties of CP, due to NEM content.
Stem Cell Aging in Skeletal Muscle Regeneration and Disease
Authors: Yamakawa Hiroyuki , Kusumoto Dai , Hashimoto Hisayuki , Yuasa Shinsuke
Published: March 2020

Skeletal muscle comprises 30–40% of the weight of a healthy human body and is required for voluntary movements in humans. Mature skeletal muscle is formed by multinuclear cells, which are called myofibers. Formation of myofibers depends on the proliferation, differentiation, and fusion of muscle progenitor cells during development and after injury. Muscle progenitor cells are derived from muscle satellite (stem) cells (MuSCs), which reside on the surface of the myofiber but beneath the basement membrane. MuSCs play a central role in postnatal maintenance, growth, repair, and regeneration of skeletal muscle. In sedentary adult muscle, MuSCs are mitotically quiescent, but are promptly activated in response to muscle injury. Physiological and chronological aging induces MuSC aging, leading to an impaired regenerative capability. Importantly, in pathological situations, repetitive muscle injury induces early impairment of MuSCs due to stem cell aging and leads to early impairment of regeneration ability. In this review, we discuss (1) the role of MuSCs in muscle regeneration, (2) stem cell aging under physiological and pathological conditions, and (3) prospects related to clinical applications of controlling MuSCs.
In Vitro Vascular Network Modified to Function as Culture Platform and Angiogenic Induction Potential Test for Cancer Cells
Authors: Huttala Outi , Staff Synnöve , Heinonen Tuula , Mäenpää Johanna , Tanner Minna , Ylikomi Timo
Published: March 2020

Drug treatments have been designed to inhibit tumor angiogenesis in hope of stopping tumor growth. However, not all tumor types respond to this type of treatment. A screening method which identifies angiogenesis inducing cancer types would help predict the efficacy of angiogenesis-inhibiting drugs for the patients. Our goal is to develop (1) a cell assay to assess the angiogenic induction potential of patient-derived tumor cells, and (2) a protocol for culturing cancer cells on a vascular platform. We optimized the media composition and seeding density of cells (hASC, HUVEC, and cancer cells) to 48-, 96-, and even 384-well plate sizes to allow vascular formation and cancer cell proliferation and subsequent analysis with high throughput. The angiogenic induction potential of patient-derived cancer cells was investigated by quantifying the formation of tubular structures and the drug response of cancer cells grown on a vascular platform was evaluated using gene expression and cell viability (WST-1) assay. Immunocytochemistry was performed with von Willebrand factor, collagen IV, CD44, cytokeratin 19 and ALDH1A1. The angiogenic induction potential test was shown to be responsive to the induction of angiogenesis by cancer cells. The responses of cancer cells were different when grown on a vascular platform or on plastic, seen in gene expression level and viability results. These two protocols are promising novel tools for aiding the selection of efficient cancer drugs for personalized medicine and as an alternative cancer cell culture platform.
The Diabetes Mellitus–Atherosclerosis Connection: The Role of Lipid and Glucose Metabolism and Chronic Inflammation
Authors: Poznyak Anastasia , Grechko Andrey V. , Poggio Paolo , Myasoedova Veronika A. , Alfieri Valentina , Orekhov Alexander N.
Published: March 2020

Diabetes mellitus comprises a group of carbohydrate metabolism disorders that share a common main feature of chronic hyperglycemia that results from defects of insulin secretion, insulin action, or both. Insulin is an important anabolic hormone, and its deficiency leads to various metabolic abnormalities in proteins, lipids, and carbohydrates. Atherosclerosis develops as a result of a multistep process ultimately leading to cardiovascular disease associated with high morbidity and mortality. Alteration of lipid metabolism is a risk factor and characteristic feature of atherosclerosis. Possible links between the two chronic disorders depending on altered metabolic pathways have been investigated in numerous studies. It was shown that both types of diabetes mellitus can actually induce atherosclerosis development or further accelerate its progression. Elevated glucose level, dyslipidemia, and other metabolic alterations that accompany the disease development are tightly involved in the pathogenesis of atherosclerosis at almost every step of the atherogenic process. Chronic inflammation is currently considered as one of the key factors in atherosclerosis development and is present starting from the earliest stages of the pathology initiation. It may also be regarded as one of the possible links between atherosclerosis and diabetes mellitus. However, the data available so far do not allow for developing effective anti-inflammatory therapeutic strategies that would stop atherosclerotic lesion progression or induce lesion reduction. In this review, we summarize the main aspects of diabetes mellitus that possibly affect the atherogenic process and its relationship with chronic inflammation. We also discuss the established pathophysiological features that link atherosclerosis and diabetes mellitus, such as oxidative stress, altered protein kinase signaling, and the role of certain miRNA and epigenetic modifications.
Differences in the Outcome of Patients with COPD according to Body Mass Index
Authors: Ji Zichen , de Miguel-Díez Javier , Castro-Riera Christian Reynaldo , Bellón-Cano José María , Gallo-González Virginia , Girón-Matute Walther Iván , Jiménez-García Rodrigo , López-de Andrés Ana , Moya-Álvarez Virginia , Puente-Maestu Luis , Hernández-Vázquez Julio
Published: March 2020

Background: In chronic obstructive pulmonary disease (COPD), the “obesity paradox” is a phenomenon without a clear cause. The objective is to analyze the complications of COPD patients according to their body mass index (BMI). Methods: An observational study with a six-year prospective follow-up of 273 COPD patients who attended a spirometry test in 2011. Survival and acute events were analyzed according to the BMI quartiles. Results: A total of 273 patients were included. BMI quartiles were ≤24.23; 24.24–27.69; 27.70–31.25; ≥31.26. During the follow-up, 93 patients died. No differences were found in exacerbations, pneumonia, emergency visits, hospital admissions or income in a critical unit. Survival was lower in the quartile 1 of BMI with respect to each of the 2–4 quartiles (p-value 0.019, 0.013, and 0.004, respectively). Advanced age (hazard ratio, HR 1.06; 95% confidence interval, CI 1.03–1.09), low pulmonary function (HR 0.93; 95% CI 0.86–0.99), exacerbator with chronic bronchitis phenotype (HR 1.76; 95% CI 1.01–3.06), high Charlson (HR 1.32, 95% CI 1.18–1.49), and the quartile 1 of BMI (HR 1.99, 95% CI 1.08–3.69) were identified as risk factors independently associated with mortality. Conclusions: In COPD, low BMI conditions a lower survival, although not for having more acute events.
Comparison of Machine Learning Computed Tomography-Based Fractional Flow Reserve and Coronary CT Angiography-Derived Plaque Characteristics with Invasive Resting Full-Cycle Ratio
Authors: Baumann Stefan , Hirt Markus , Rott Christina , Özdemir Gökce H. , Tesche Christian , Becher Tobias , Weiss Christel , Hetjens Svetlana , Akin Ibrahim , Schoenberg Stefan O. , Borggrefe Martin , Janssen Sonja , Overhoff Daniel , Lossnitzer Dirk
Published: March 2020

Background: The aim is to compare the machine learning-based coronary-computed tomography fractional flow reserve (CT-FFRML) and coronary-computed tomographic morphological plaque characteristics with the resting full-cycle ratio (RFRTM) as a novel invasive resting pressure-wire index for detecting hemodynamically significant coronary artery stenosis. Methods: In our single center study, patients with coronary artery disease (CAD) who had a clinically indicated coronary computed tomography angiography (cCTA) and subsequent invasive coronary angiography (ICA) with pressure wire-measurement were included. On-site prototype CT-FFRML software and on-site CT-plaque software were used to calculate the hemodynamic relevance of coronary stenosis. Results: We enrolled 33 patients (70% male, mean age 68 ± 12 years). On a per-lesion basis, the area under the receiver operating characteristic curve (AUC) of CT-FFRML (0.90) was higher than the AUCs of the morphological plaque characteristics length/minimal luminal diameter4 (LL/MLD4; 0.80), minimal luminal diameter (MLD; 0.77), remodeling index (RI; 0.76), degree of luminal diameter stenosis (0.75), and minimal luminal area (MLA; 0.75). Conclusion: CT-FFRML and morphological plaque characteristics show a significant correlation to detected hemodynamically significant coronary stenosis. Whole CT-FFRML had the best discriminatory power, using RFRTM as the reference standard.