bluuebunny/crossref_metadata_2025 huggingface dataset:
Property Data Estimation for Hemiformals, Methylene Glycols and Polyoxymethylene Dimethyl Ethers and Process Optimization in Formaldehyde Synthesis
Authors: Schemme Steffen , Meschede Sven , Köller Maximilian , Samsun Remzi Can , Peters Ralf , Stolten Detlef
Published: July 2020

Polyoxymethylene dimethyl ethers (OMEn) are frequently discussed as alternative diesel fuels, with various synthesis routes considered. OME3–5 syntheses demand significant amounts of thermal energy due to the complex separation processes that they entail. Therefore, innovative process designs are needed. An important tool for the development of new processes is process simulation software. To ensure sound process simulations, reliable physico-chemical models and component property data are necessary. Herein we present the implementation of a state-of-the-art thermodynamic model to describe the component systems of formaldehyde-water and formaldehyde-methanol using Microsoft® Excel (2010, Microsoft Corp, Redmond, WA, USA) and Aspen Plus®, (V8.8, Aspen Tech, Bedford, MA, USA) determine the deviation between the calculated results and experimental literature data, and minimize the deviation by means of parameter fitting. To improve the accuracy of the estimation of the missing property data of hemiformals and methylene glycols formed from formaldehyde using group contribution methods, the normal boiling points were estimated based on molecular analogies. The boiling points of OME6-10 are determined through parameter regression in accordance with the vapor pressure equation. As an application example, an optimization of the product separation of the state-of-the-art formaldehyde synthesis is presented that helps decrease the losses of methanol and formaldehyde in flue gas and wastewater.
Thermal Performance Analysis of a Solar Reactor Designed for Syngas Production
Authors: Getahun Dessie Yabibal , Guene Lougou Bachirou , Hong Qi , Heping Tan , Juqi Zhang , Baohai Gao , Md Arafat Islam
Published: July 2020

The design elements considered during the construction of a thermochemical reactor determine its thermal performance. This current study investigated the effect of design elements, such as boundary layer thickness, insulating materials for the outlet tube design and fluid inlet locations of the frustum, on the thermal performance of a proposed syngas production reactor with incident radiation heat transfer through quartz glass. The P1 radiation approximation model and fluid flow in the shallow path were integrated into a proposed radiation model. The result indicated that inlet mass flow rates from 5 × 10−4 to 14 × 10−4 kg/s increased the temperature in the cavity and the outlet. The fluid inlet located at the top of the quartz glass edges was found to have better thermal performance and maximum average outlet temperature. Insulation for fluid inlets tube above the quartz glass edges of the frustum was very important for the prevention of radiation loss through quartz glass and sedimentation of fluid particles around the quartz glass edge, and the facilitation of fast heat transfer towards the internal part of the reactor. The outlet that was a tube designed using an aluminum oxide-type insulator with a 50 mm boundary layer thickness was found to increase the average outlet temperature of the reactor. This study revealed that fluid entry and exit locations on the frustum and proper fluid outlet design were critical for the thermal performance analysis of the solar thermochemical reactor for heat transfer with quartz glass. Findings from this study will be of relevance to chemical and power engineering sectors, as well as academia.
Estimating the Remaining Power Generation of Wind Turbines—An Exploratory Study for Main Bearing Failures
Authors: Wiese Benedikt , Pedersen Niels L. , Nadimi Esmaeil S. , Herp Jürgen
Published: July 2020

Condition monitoring for wind turbines is tailored to predict failure and aid in making better operation and maintenance (O&M) decisions. Typically the condition monitoring approaches are concerned with predicting the remaining useful lifetime (RUL) of assets or a component. As the time-based measures can be rendered absolute when changing the operational set-point of a wind turbine, we propose an alternative in a power-based condition monitoring framework for wind turbines, i.e., the remaining power generation (RPG) before a main bearing failure. The proposed model utilizes historic wind turbine data, from both run-to-failure and non run-to-failure turbines. Comprised of a recurrent neural network with gated recurrent units, the model is constructed around a censored and uncensored data-based cost function. We infer a Weibull distribution over the RPG, which gives an operator a measure of how certain any given prediction is. As part of the model evaluation, we present the hyper-parameter selection, as well as modeling error in detail, including an analysis of the driving features. During the application on wind turbine main bearing failures, we achieve prediction in the magnitude of 1 to 2 GWh before the failure. When converting to RUL this corresponds to predicting the failure, on average, 81 days beforehand, which is comparable to the state-of-the-art’s 94 days predictive horizon in a similar feature space.
Virtual Simulation of Electric Bus Fleets for City Bus Transport Electrification Planning
Authors: Topić Jakov , Soldo Jure , Maletić Filip , Škugor Branimir , Deur Joško
Published: July 2020

City bus transport electrification has a strong potential of improving city air quality, reducing noise pollution and increasing passenger satisfaction. Since the city bus operation is rather deterministic and intermittent, the driving range- and charging-related concerns may be effectively overcome by means of fast charging at end stations and/or slow charging in depot. In order to support decision making processes, a simulation tool for planning of city bus transport electrification has been developed and it is presented in this paper. The tool is designed to use real/recorded driving cycles and techno-economic data, in order to calculate the optimal type and number of e-buses and chargers, and predict the total cost of ownership including investment and exploitation cost. The paper focuses on computationally efficient e-bus fleet simulation including powertrain control and charging management aspects, which is illustrated through main results of a pilot study of bus transport electrification planning for the city of Dubrovnik.
Disc Granulation Process of Carbonation Lime Mud as a Method of Post-Production Waste Management
Authors: Ławińska Katarzyna , Szufa Szymon , Obraniak Andrzej , Olejnik Tomasz , Siuda Robert , Kwiatek Jerzy , Ogrodowczyk Dominika
Published: July 2020

Carbonation lime mud is a by-product formed during the production of sugar in the process of raw beetroot juice purification. On average, during one campaign, over 12,000 tons of carbonation lime mud is obtained in the operation of one sugar production plant. It is stored in prisms, which negatively affects the environment. The chemical properties of carbonation lime mud allow using it as a soil improver. This article presents the results of research into the development of carbonation lime mud disposal technology and its management. The chemical composition and physical properties of waste were determined. It has been proposed to use carbonation lime mud as the basic raw material in the production of mineral–organic fertilizers. Tests were conducted in a disc granulator. The granulated material was wetted with water and aqueous solution of molasses. Carbonation lime mud is a material that is easily subjected to the granulation process, using any wetting liquid. The beds wetted with 33% and 66% solutions of molasses are characterized by a greater homogeneity and smaller size of the obtained product. During experiments in which wetting with water was applied, the product obtained after drying demonstrated low resistance to compression; granules wetted with 33% aqueous solution of molasses demonstrated resistance to compression below 10 N; and granules wetted with 66% aqueous solution of molasses demonstrated resistance to compression above 10 N.
Wind Power Long-Term Scenario Generation Considering Spatial-Temporal Dependencies in Coupled Electricity Markets
Authors: Marulanda Geovanny , Bello Antonio , Cifuentes Jenny , Reneses Javier
Published: July 2020

Wind power has been increasing its participation in electricity markets in many countries around the world. Due to its economical and environmental benefits, wind power generation is one of the most powerful technologies to deal with global warming and climate change. However, as wind power grows, uncertainty in power supply increases due to wind intermittence. In this context, accurate wind power scenarios are needed to guide decision-making in power systems. In this paper, a novel methodology to generate realistic wind power scenarios for the long term is proposed. Unlike most of the literature that tackles this problem, this paper is focused on the generation of realistic wind power production scenarios in the long term. Moreover, spatial-temporal dependencies in multi-area markets have been considered. The results show that capturing the dependencies at the monthly level could improve the quality of scenarios at different time scales. In addition, an evaluation at different time scales is needed to select the best approach in terms of the distribution functions of the generated scenarios. To evaluate the proposed methodology, several tests have been made using real data of wind power generation for Spain, Portugal and France.
T’imani a Multifunctional Solar System to Provide Cooking and Water Heating Rural Energy Needs
Authors: Rodríguez Morales José Ángel , González-Avilés Mauricio , Servín Campuzano Hermelinda , Masera Omar
Published: July 2020

This study describes the development of a multifunctional solar system designed for implementation in some communities in the Meseta Purepecha, Michoacan, Mexico. The multifunctional solar system device—called T’imani (in the Purepecha language)— consists of two modules designed for domestic use: one for cooking food, the other for heating water. The thermal characterization is based on the use of standardized tests for both modules. The parameters obtained indicate that use device is suitable for in the conditions of solar resources in this region. Additionally, a pilot test was carried out to implement some devices that show favorable preliminary results for domestic use. Hence, due to the device functionality and that in Mexico there is abundant solar resources it is feasible to implement the device in many places throughout the country.
Performance Assessment of an Energy Management System for a Home Microgrid with PV Generation
Authors: Elkazaz Mahmoud , Sumner Mark , Pholboon Seksak , Davies Richard , Thomas David
Published: July 2020

Home energy management systems (HEMS) are a key technology for managing future electricity distribution systems as they can shift household electricity usage away from peak consumption times and can reduce the amount of local generation penetrating into the wider distribution system. In doing this they can also provide significant cost savings to domestic electricity users. This paper studies a HEMS which minimizes the daily energy costs, reduces energy lost to the utility, and improves photovoltaic (PV) self-consumption by controlling a home battery storage system (HBSS). The study assesses factors such as the overnight charging level, forecasting uncertainty, control sample time and tariff policy. Two management strategies have been used to control the HBSS; (1) a HEMS based on a real-time controller (RTC) and (2) a HEMS based on a model predictive controller (MPC). Several methods have been developed for home demand energy forecasting and PV generation forecasting and their impact on the HEMS is assessed. The influence of changing the battery’s capacity and the PV system size on the energy costs and the lost energy are also evaluated. A significant reduction in energy costs and energy lost to the utility can be achieved by combining a suitable overnight charging level, an appropriate sample time, and an accurate forecasting tool. The HEMS has been implemented on an experimental house emulation system to demonstrate it can operate in real-time.
Power System Stability with Power-Electronic Converter Interfaced Renewable Power Generation: Present Issues and Future Trends
Authors: Meegahapola Lasantha , Sguarezi Alfeu , Bryant Jack Stanley , Gu Mingchen , Conde D. Eliomar R. , Cunha Rafael B. A.
Published: July 2020

The energy sector is currently undergoing a rapid transformation with the integration of power electronic converter (PEC)-interfaced renewable energy sources (RES), such as wind and solar photovoltaic (PV) systems, at both the transmission and distribution networks. Power system stability has been significantly influenced by this power grid transformation. This paper comprehensively reviews major power system stability issues affected due to large-scale integration of PEC-interfaced RES in power grids, with some example case studies relevant for each stability category. According to the review, stability issues are mainly originating from reduction in synchronous inertia, reduction in reactive power reserve, low short-circuit strength of the power network, and fault ride-through (FRT) strategy/capability of the PEC-interfaced RES. Decrease in synchronous inertia could affect both the rotor angle stability and the frequency stability, while decrease in short-circuit strength and reactive power reserve could cause voltage stability and rotor angle stability issues in power networks. Sub-synchronous control interactions are also receiving a lot of attention by the power industry due to increasing oscillatory stability incidents reported in power networks with PEC-interfaced RES. FRT capabilities/strategies of PEC-interfaced RES are also playing a pivotal role in power grid stability due to its influence on active and reactive power, hence more emphasis should be placed on FRT schemes of PEC-interfaced RES, since future power grids are expected to operate with 100% PEC-interfaced generation sources. Stability improvement strategies could be implemented to address multiple stability issues in PEC-interfaced power networks; however, rigorous stability studies are required to identify the optimal conditions to implement these improvement strategies. Furthermore, ongoing structural changes in power grids to accommodate remotely sited PEC-interfaced RES are also influencing the stability of power grids. Therefore, all these factors must be carefully considered by system operators when planning and operating power grids in a secure and stable manner with high penetration levels of PEC-interfaced RES.
Local Market for TSO and DSO Reactive Power Provision Using DSO Grid Resources
Authors: Retorta Fábio , Aguiar João , Rezende Igor , Villar José , Silva Bernardo
Published: July 2020

This paper proposes a near to real-time local market to provide reactive power to the transmission system operator (TSO), using the resources connected to a distribution grid managed by a distribution system operator (DSO). The TSO publishes a requested reactive power profile at the TSO-DSO interface for each time-interval of the next delivery period, so that market agents (managing resources of the distribution grid) can prepare and send their bids accordingly. DSO resources are the first to be mobilized, and the remaining residual reactive power is supplied by the reactive power flexibility offered in the local reactive market. Complex bids (with non-curtailability conditions) are supported to provide flexible ways of bidding fewer flexible assets (such as capacitor banks). An alternating current (AC) optimal power flow (OPF) is used to clear the bids by maximizing the social welfare to supply the TSO required reactive power profile, subject to the DSO grid constraints. A rolling window mechanism allows a continuous dispatching of reactive power, and the possibility of adapting assigned schedules to real time constraints. A simplified TSO-DSO cost assignment of the flexible reactive power used is proposed to share for settlement purposes.
Methane Derived Authigenic Carbonate (MDAC) Aragonite Cemented Quaternary Hardground from a Methane Cold Seep, Rathlin Basin, Northern Ireland: δ13C and δ18O Isotopes, Environment, Porosity and Permeability
Authors: Buckman Jim , Donnelly Terry , Jiang Zeyun , Lewis Helen , Ruffell Alastair
Published: July 2020

A block of sandstone retrieved by divers from near Rathlin Island, Co. Antrim, Northern Ireland, represents an aragonite cemented sand formed during the Quaternary. Strongly negative δ13C of the aragonite cement (−50 to −60‰ δ13C) indicates that the hardground was formed by the anaerobic oxidation of methane (AOM), resulting in the formation of a methane-derived authigenic carbonate (MDAC) hardground. Such hardgrounds have previously been recorded as forming extensive pavements in deeper waters in the mid Irish Sea (e.g., Croker Carbonate Slabs), although the latter also contains high-magnesium calcite. Sand was initially deposited as part of a storm lag deposit, with a reworked bivalve and gastropod fauna. This sand was then colonised by a probable crustacean fauna, producing horizontal open dwelling burrows (Thalassinoides). After aragonite cementation, the hardground was colonised by boring bivalves, with slightly negatively elevated levels of δ13C. Finally, the hardground was colonised by an encrusting fauna (bryozoans, calcareous algae and serpulids), by then in warmer seas. Continued depleted levels of δ13C present within the encrusting fauna (−1 to −5‰ δ13C) indicate continued methane generation and seepage, which may still be active to the present day, and to the possibility of shallow gas reserves. The δ18O values change between macro-infauna vs. encrusters, indicating a warming in water temperature, reflecting glacial and post-glacial environments. The aragonite cemented sandstone has a highly variable porosity, with large vugs (open burrows and borings), smaller mouldic porosity within gastropods and bivalves and complex micro-porosity associated with acicular aragonite cements. Overall permeability was recorded at the 2.5 to 23 Darcies level, reflecting the highly variable vuggy porosity, although matrix permeability was around 100 mD and controlled by the MDAC fabric. Actual permeability will likely be controlled by the extent to which larger pores are interconnected. The sea around the Rathlin Island area contains a diverse fauna, which is worthy of future study in the context of cold seep and MDAC pavement formation.
Comparison of Cortisol level by Shift Cycle in Korean Firefighters
Authors: Lim Ga-Young , Jang Tae-Won , Sim Chang-Sun , Ahn Yeon Soon , Jeong Kyoung Sook
Published: July 2020

(1) Study Objectives: By investigating the change of cortisol levels during shift cycles among professional firefighters in Korea, this study aims to evaluate the difference between individuals’ stress response and the recovery of their circadian rhythm after working night shifts. (2) Methods: A total of 325 shift firefighters, who were working in 3, 6, 9, or 21 day cycles, participated in the study. Their urinary and serum cortisol levels were measured during the day (09–18), during the night (18–09), and every 24 h (09–09) per shift cycle, and adjustments were made for confounding factors. (3) Results: Serum cortisol levels were significantly increased after working during the night or for 24 h compared with that of working throughout the day. However, whether working night or 24 h shifts, the serum cortisol levels were undoubtedly different based on the 3, 6, 9, or 21 day cycles. In all shift cycles, the urinary cortisol level decreased during the night or throughout the 24 h shifts compared with sleeping during this time, but this was considered to be significantly applicable only to those working in 21 day cycles. Additionally, in serial measurements, the recovery of urinary cortisol secretion after a night or 24 h shift was successful for individuals working in 9 day cycles, but the recovery was delayed for those working in 6 or 21 day cycles. (4) Conclusions: After analyzing the urine cortisol levels, the study indicates that only subjects working in 9 day cycles fully recovered their circadian rhythm while those working in 6 day or 21 day cycles did not completely recover. Therefore, it is important to recognize how stressful night shifts can be, and it is crucial to enhance firefighters’ current shift cycles in order to allow sufficient recovery of their circadian rhythm as well as the prevention of disrupting their circadian rhythm after working at night. Further research is necessary to take into account the amount of work load, the challenges of being sleep deprived, and the individual’s capacity to overcome sleepiness.
Economic Effects of Renewable Energy Expansion Policy: Computable General Equilibrium Analysis for Korea
Authors: Oh Inha , Yoo Wang-Jin , Kim Kihwan
Published: July 2020

This study examines the effects of renewable energy expansion policy on the Korean economy and industries using the computable general equilibrium model, which divides the power generation sector into detailed generation technologies and sources. The scenarios are set to observe the cases where the share of solar photovoltaic and wind power generation reaches 7%. The effects are examined according to differing circumstances, such as when greenhouse gas (GHG) emissions are regulated, and the funding source for renewable expansion varies. The results show that renewable expansion policies have negative effects on GDP. However, the magnitude of the GDP decline becomes smaller when GHG emissions are regulated. The expansion of renewable energy induces the growth of upstream industries which supply components for renewable generation modules. Regarding employment, the renewable expansion policy can increase the demand for labor. However, the direction and the extent of the effect vary depending on the funding source. When overlapping regulations, such as the emission trading scheme and renewable energy expansion policies, exist in the power generation sector, the renewable energy expansion policy could provide incentives for GHG emission-intensive power sources.
Levels of Physical Activity during School Hours in Children and Adolescents: A Systematic Review
Authors: Grao-Cruces Alberto , Velázquez-Romero María J. , Rodríguez-Rodríguez Fernando
Published: July 2020

Background: This systematic review determines the levels of physical activity (PA) during school hours in children and adolescents. Methods: Studies carried out from January 1987 to December 2019 were retrieved from four databases (Web of Science, Pubmed, Scopus and SportDiscus). Results: Twenty-nine studies were included in this systematic review. Most of them used accelerometers and showed that male and female children accumulated a mean of between 14 and 68 min of moderate-to-vigorous PA (MVPA) during school hours (3–22% of this daily segment), and male and female adolescents accumulated a mean of between 13 and 28 min of MVPA during this daily segment (3–8% of the school hours). Less than a quarter of children and adolescents reached the recommended 30 min of MVPA during school hours, with notable differences between sexes. Conclusions: These results suggest that the levels of PA during school hours are not enough, and consequently, schools should develop strategies for helping children and adolescents reach the school PA recommendation.
Location Choice in the Context of Older Adults’ Leisure-Time Walking
Authors: Liu Zhengying , Kemperman Astrid , Timmermans Harry
Published: July 2020

Leisure-time walking is the most prevalent and preferred form of physical activity of older adults. In order to promote leisure-time walking and enhance the efficiency of using outdoor open spaces, the supply of different types of walking locations should match the needs, interests and preferences of older adults. However, there is limited knowledge on which location types are chosen by which groups of individuals under which conditions. This study therefore examines the effects of socio-demographics, episode participation attributes and neighborhood characteristics on the location choice of older adults for leisure-time walking. A multinomial logit model is estimated based on data collected among 316 respondents aged 60 or older in Dalian, China. The results indicate that older people’s location choices for walking are associated with their socio-demographics, episode participation attributes and neighborhood characteristics. Finally, implications of the results for the planning, design and management of open spaces are identified.
Bullying Experience among Adolescents with a Turkish Migration Background in Germany: Ethnic Class Composition, Integration, and Religiosity as Protective Factors?
Authors: Demmrich Sarah , Akgül Semra
Published: July 2020

Bullying is a worldwide problem that has serious effects on the mental health of both victims and perpetrators. Although bullying seems related to increasing globalization and migration, it has seldom been researched in this context. This exploratory study examined bullying experiences and related depressive symptoms among a sample of adolescents with a Turkish migration background in a German school context (N = 103, 56.7% female, MAge = 16.17, SDAge = 1.36). The study focuses on three migration-related variables as potentially salutogenic factors: Ethnic class composition, acculturation, and religiosity. While the ethnic class composition did not show any effect, an integration acculturation strategy and religiosity proved to be protective factors against bullying experience. The negative prediction of integration on depressive symptoms was not consistent throughout the multivariate analyses. The results are discussed against the background of new impulses for bullying intervention programs for this vulnerable group of adolescents from a Turkish migration background.
Analyzing the Association between Hyperuricemia and Periodontitis: A Cross-Sectional Study Using KoGES HEXA Data
Authors: Byun Soo-Hwan , Yoo Dae-Myoung , Lee Jung-Woo , Choi Hyo-Geun
Published: July 2020

Hyperuricemia arises from the buildup of excessive uric acid in the blood, and it is implicated in the development of periodontitis. The objective of this study was to investigate the association between hyperuricemia and periodontitis using a cross-sectional study design and Korean Genome and Epidemiology Study Health Examinee (KoGES HEXA) data. This prospective cohort study used epidemiological data from the KoGES from 2004 to 2016. Among 173,209 participants, 8809 with hyperuricemia and 126,465 controls (non-hyperuricemia) were selected. This study defined hyperuricemia as >7.0 mg/dL of uric acid in men and >6.0 mg/dL in women. This study analyzed the history of periodontitis among hyperuricemia and control participants. Participants’ age, gender, income, obesity, smoking, alcohol consumption, and nutritional intake were all examined. Chi-square tests, independent t-tests, and two-tailed analyses were used for statistical analysis. The adjusted OR (aOR) of hyperuricemia for periodontitis was 0.89 (95% confidence interval (CI) = 0.81–0.96, p = 0.005). This study demonstrated that hyperuricemia was associated with periodontitis. This finding meant that elevated uric acid levels could have a positive effect on periodontitis. However, further studies should be performed to determine the range of uric acid levels beneficial to periodontal health.
Effects of Covid-19 Lockdown on Mental Health and Sleep Disturbances in Italy
Authors: Gualano Maria Rosaria , Lo Moro Giuseppina , Voglino Gianluca , Bert Fabrizio , Siliquini Roberta
Published: July 2020

Italy was the first European country that entered a nationwide lockdown during the COVID-19 pandemic. Since quarantine can impact on mental health, this study aimed to estimate the prevalence of depressive symptoms, anxiety symptoms and sleeping disturbances in the Italian population during lockdown. The factors that might influence such outcomes were explored. A national cross-sectional survey was performed during the last 14 days of the Italian lockdown. Questionnaires assessed socio-demographics characteristic, behaviors and healthcare access. The outcomes were assessed using Patient Health Questionnaire-2 and Generalized Anxiety Disorder-2. Participants with sleep disturbances completed the Insomnia Severity Index. The sample size was 1515. Depression and anxiety symptom prevalence was 24.7% and 23.2%; 42.2% had sleep disturbances and, among them, 17.4% reported moderate/severe insomnia. Being female, an increased time spent on the internet and an avoidance of activities through peer pressure increased the likelihood of at least one mental health outcome. Increasing age, an absence of work-related troubles and being married or being a cohabitant reduced such a probability. Females and participants with chronic conditions were associated with a higher prevalence of sleep disturbances. It is crucial to study effective interventions, specifically planning strategies, for more vulnerable groups and to consider the role of the internet.
Simultaneous Pre-Concentration and HPLC-MS/MS Quantification of Phycotoxins and Cyanotoxins in Inland and Coastal Waters
Authors: Merlo Francesca , Maraschi Federica , Piparo Davide , Profumo Antonella , Speltini Andrea
Published: July 2020

The purpose of this study was to set up a sensitive method for the simultaneous determination of phycotoxins and cyanotoxins—Emerging pollutants with different structures and harmful properties (hepatotoxicity, neurotoxicity and cytotoxicity)—In environmental waters. Due to the low concentrations detected in these samples, a pre-concentration step is required and here it was performed in a single step with a commercial cartridge (Strata™-X), achieving enrichment factors up to 200 and satisfactory recovery (R = 70–118%) in different aqueous matrices. After solid-phase extraction (SPE), toxins were separated and quantified by High Performance Liquid Chromatography- Heated ElectroSpray Ionisation Tandem Mass Spectrometry (HPLC-HESI-MS/MS) in Multiple Reaction Monitoring (MRM) mode. An analytical evaluation of the proposed method was done based on the analytical figures of merit, such as precision and trueness, linearity, selectivity, and sensitivity, and it turned out to be a robust tool for the quantification of ng L−1 levels, phycotoxins and cyanotoxins in both freshwater and saltwater samples.
Forecasting of Landslide Displacement Using a Probability-Scheme Combination Ensemble Prediction Technique
Authors: Ma Junwei , Liu Xiao , Niu Xiaoxu , Wang Yankun , Wen Tao , Zhang Junrong , Zou Zongxing
Published: July 2020

Data-driven models have been extensively employed in landslide displacement prediction. However, predictive uncertainty, which consists of input uncertainty, parameter uncertainty, and model uncertainty, is usually disregarded in deterministic data-driven modeling, and point estimates are separately presented. In this study, a probability-scheme combination ensemble prediction that employs quantile regression neural networks and kernel density estimation (QRNNs-KDE) is proposed for robust and accurate prediction and uncertainty quantification of landslide displacement. In the ensemble model, QRNNs serve as base learning algorithms to generate multiple base learners. Final ensemble prediction is obtained by integration of all base learners through a probability combination scheme based on KDE. The Fanjiaping landslide in the Three Gorges Reservoir area (TGRA) was selected as a case study to explore the performance of the ensemble prediction. Based on long-term (2006–2018) and near real-time monitoring data, a comprehensive analysis of the deformation characteristics was conducted for fully understanding the triggering factors. The experimental results indicate that the QRNNs-KDE approach can perform predictions with perfect performance and outperform the traditional backpropagation (BP), radial basis function (RBF), extreme learning machine (ELM), support vector machine (SVM) methods, bootstrap-extreme learning machine-artificial neural network (bootstrap-ELM-ANN), and Copula-kernel-based support vector machine quantile regression (Copula-KSVMQR). The proposed QRNNs-KDE approach has significant potential in medium-term to long-term horizon forecasting and quantification of uncertainty.
Change Detection from Remote Sensing to Guide OpenStreetMap Labeling
Authors: Albrecht Conrad M. , Zhang Rui , Cui Xiaodong , Freitag Marcus , Hamann Hendrik F. , Klein Levente J. , Finkler Ulrich , Marianno Fernando , Schmude Johannes , Bobroff Norman , Zhang Wei , Siebenschuh Carlo , Lu Siyuan
Published: July 2020

The growing amount of openly available, meter-scale geospatial vertical aerial imagery and the need of the OpenStreetMap (OSM) project for continuous updates bring the opportunity to use the former to help with the latter, e.g., by leveraging the latest remote sensing data in combination with state-of-the-art computer vision methods to assist the OSM community in labeling work. This article reports our progress to utilize artificial neural networks (ANN) for change detection of OSM data to update the map. Furthermore, we aim at identifying geospatial regions where mappers need to focus on completing the global OSM dataset. Our approach is technically backed by the big geospatial data platform Physical Analytics Integrated Repository and Services (PAIRS). We employ supervised training of deep ANNs from vertical aerial imagery to segment scenes based on OSM map tiles to evaluate the technique quantitatively and qualitatively.
Stimuli-Responsive Materials for Tissue Engineering and Drug Delivery
Authors: Municoy Sofia , Álvarez Echazú María I. , Antezana Pablo E. , Galdopórpora Juan M. , Olivetti Christian , Mebert Andrea M. , Foglia María L. , Tuttolomondo María V. , Alvarez Gisela S. , Hardy John G. , Desimone Martin F.
Published: July 2020

Smart or stimuli-responsive materials are an emerging class of materials used for tissue engineering and drug delivery. A variety of stimuli (including temperature, pH, redox-state, light, and magnet fields) are being investigated for their potential to change a material’s properties, interactions, structure, and/or dimensions. The specificity of stimuli response, and ability to respond to endogenous cues inherently present in living systems provide possibilities to develop novel tissue engineering and drug delivery strategies (for example materials composed of stimuli responsive polymers that self-assemble or undergo phase transitions or morphology transformations). Herein, smart materials as controlled drug release vehicles for tissue engineering are described, highlighting their potential for the delivery of precise quantities of drugs at specific locations and times promoting the controlled repair or remodeling of tissues.
Statin Treatment-Induced Development of Type 2 Diabetes: From Clinical Evidence to Mechanistic Insights
Authors: Galicia-Garcia Unai , Jebari Shifa , Larrea-Sebal Asier , Uribe Kepa B. , Siddiqi Haziq , Ostolaza Helena , Benito-Vicente Asier , Martín César
Published: July 2020

Statins are the gold-standard treatment for the prevention of primary and secondary cardiovascular disease, which is the leading cause of mortality worldwide. Despite the safety and relative tolerability of statins, observational studies, clinical trials and meta-analyses indicate an increased risk of developing new-onset type 2 diabetes mellitus (T2DM) after long-term statin treatment. It has been shown that statins can impair insulin sensitivity and secretion by pancreatic β-cells and increase insulin resistance in peripheral tissues. The mechanisms involved in these processes include, among others, impaired Ca2+ signaling in pancreatic β-cells, down-regulation of GLUT-4 in adipocytes and compromised insulin signaling. In addition, it has also been described that statins’ impact on epigenetics may also contribute to statin-induced T2DM via differential expression of microRNAs. This review focuses on the evidence and mechanisms by which statin therapy is associated with the development of T2DM. This review describes the multifactorial combination of effects that most likely contributes to the diabetogenic effects of statins. Clinically, these findings should encourage clinicians to consider diabetes monitoring in patients receiving statin therapy in order to ensure early diagnosis and appropriate management.
Identification of Matrine as a Novel Regulator of the CXCR4 Signaling Axis in Tumor Cells
Authors: Jung Young Yun , Um Jae-Young , Narula Acharan S. , Namjoshi Ojas A. , Blough Bruce E. , Kumar Alan Prem , Ahn Kwang Seok
Published: July 2020

Matrine, a quinolizidine alkaloid, is commonly employed for treating various viral and inflammatory disorders. Here, we have evaluated matrine for its activity on C-X-C chemokine receptor type 4 (CXCR4) and matrix metalloproteinases (MMP-9/2) expression, and its potential to affect tumor metastasis and invasion. The effects of matrine on CXCR4, MMP-9/2, and nuclear factor κB (NF-κB) activation in lung (A549), prostate (DU145), and pancreas (MIA PaCa-2) cells were investigated by diverse techniques. The expression level of CXCR4 and MMP-9/2 was analyzed by western blot analysis and reverse transcription polymerase chain reaction. NF-κB activation was also evaluated by western blot analysis, electrophoretic mobility shift assay as well as immunocytochemical experiments. Furthermore, we monitored cell invasion and metastasis activities by wound healing and Boyden chamber assays. We noted that matrine induced a down-regulation of CXCR4 and MMP-9/2 at both protein and mRNA levels. In addition, matrine negatively regulated human epidermal growth factor receptor 2 (HER2) and C-X-C Motif Chemokine Ligand 12 (CXCL12)-induced CXCR4 expression. Moreover, NF-κB suppression by matrine led to inhibition of metastatic potential of tumor cells. Our results suggest that matrine can block the cancer metastasis through the negative regulation of CXCR4 and MMP-9/2 and consequently it can be considered as a potential candidate for cancer therapy.
Nintedanib Reduces Neutrophil Chemotaxis via Activating GRK2 in Bleomycin-Induced Pulmonary Fibrosis
Authors: Chen Wei-Chih , Chen Nien-Jung , Chen Hsin-Pai , Yu Wen-Kuang , Su Vincent Yi-Fong , Chen Hao , Wu Huai-Hsuan , Yang Kuang-Yao
Published: July 2020

Neutrophils are involved in the alveolitis of idiopathic pulmonary fibrosis (IPF). However, their pathogenic mechanisms are still poorly understood. Nintedanib has antifibrotic and anti-inflammatory activity in IPF. This study aimed to investigate the regulatory mechanism of nintedanib on neutrophil chemotaxis in bleomycin (BLM)-induced pulmonary fibrosis. Nintedanib was administered via oral gavage to male C57BL/6 mice 24 h after a bleomycin intratracheal injection (1.5 U/kg). Lung histopathological findings, the expression of cytokines, and the regulatory signaling pathways of neutrophil chemotaxis were analyzed. The effect of nintedanib was also investigated in a mouse model with adoptive neutrophil transfer in vivo. Nintedanib significantly decreased the histopathological changes and neutrophil recruitment in BLM-induced pulmonary fibrosis. Nintedanib mediated a downregulation of chemokine (C-X-C motif) receptor 2 (CXCR2) and very late antigen 4 (VLA-4) expression, as well as an upregulation of G protein-coupled receptor kinase 2 (GRK2) activity in peripheral blood neutrophils in BLM-induced pulmonary fibrosis. Nintedanib also decreased the activation of endothelial cells by the decreased expression of vascular cell adhesion molecule 1 (VCAM-1). The effect of nintedanib on regulating neutrophil chemotaxis was also confirmed by a mouse model with adoptive neutrophil transfer in vivo. In conclusion, nintedanib reduces neutrophil chemotaxis and endothelial cell activation to regulate the severity of BLM-induced pulmonary fibrosis. These effects are associated with an enhancement of GRK2 activity and a reduction in CXCR2 and VLA-4 expression on neutrophils and a decrease in VCAM-1 expression on endothelial cells.
Shedding “LIGHT” on the Link between Bone and Fat in Obese Children and Adolescents
Authors: Brunetti Giacomina , Faienza Maria Felicia , Piacente Laura , Storlino Giuseppina , Oranger Angela , D'Amato Gabriele , De Filippo Gianpaolo , Colucci Silvia , Grano Maria
Published: July 2020

Obesity may affect bone health, but literature reports are contradictory about the correlation of body mass index (BMI) and bone markers. LIGHT, one of the immunostimulatory cytokines regulating the homeostasis of bone and adipose tissue, could be involved in obesity. The study involved 111 obese subjects (12.21 ± 3.71 years) and 45 controls. Patients underwent the evaluation of bone status by quantitative ultrasonography (QUS). LIGHT amounts were evaluated in sera by ELISA, whereas its expression on peripheral blood cells was evaluated by flow cytometry. Osteoclastogenesis was performed by culturing peripheral blood mononuclear cells (PBMCs) with or without anti-LIGHT antibodies. Obese patients showed significant high BMI-standard deviation score (SDS), weight-SDS, and Homeostatic model assessment for insulin resistance (HOMA-IR) that negatively correlated with the reduced Amplitude Dependent Speed of Sound (AD-SoS)-Z-score and Bone Transmission Time (BTT-Z)-score. They displayed significantly higher serum levels of LIGHT compared with controls (497.30 ± 363.45 pg/mL vs. 186.06 ± 101.41 pg/mL, p < 0.001). LIGHT expression on monocytes, CD3+-T-cells, and neutrophils was also higher in obese patients than in the controls. Finally, in PBMC cultures, the addition of anti-LIGHT antibodies induced a significant osteoclastogenesis inhibition. Our study highlighted the high serum levels of LIGHT in obese children and adolescents, and its relationship with both the grade of obesity and bone impairment.
The HSP90 Inhibitor, AUY-922, Ameliorates the Development of Nitrogen Mustard-Induced Pulmonary Fibrosis and Lung Dysfunction in Mice
Authors: Solopov Pavel , Colunga Biancatelli Ruben M. L. , Marinova Margarita , Dimitropoulou Christiana , Catravas John D.
Published: July 2020

Increased levels of heat shock protein 90 (HSP90) have been recently implicated in the pathogenesis of pulmonary fibrosis and the use of HSP90 inhibitors constitutes a potential therapeutic approach. Similarly, acute exposure to nitrogen mustard (NM) is related to the development of chronic lung injury driven by TNF-α, TGF-β, ERK and HSP90. Thus, we developed a murine model of NM-induced pulmonary fibrosis by instilling C57BI/6J mice with 0.625 mg/kg mechlorethamine hydrochloride. After 24 h, mice began receiving AUY-922, a second generation HSP90 inhibitor, at 1 mg/kg 2 times per week or 2 mg/kg 3 times per week, for either 10 or 30 days. AUY-922 suppressed the NM-induced sustained inflammation, as reflected in the reduction of leukocyte and protein concentrations in bronchoalveolar lavage fluid (BALF), and inhibited the activation of pro-fibrotic biomarkers, ERK and HSP90. Furthermore, AUY-922 maintained normal lung function, decreased the overexpression and accumulation of extracellular matrix proteins, and dramatically reduced histologic evidence of fibrosis in the lungs of mice exposed to NM. The HSP90 inhibitor, AUY-922, successfully blocked the adverse effects associated with acute exposures to NM, representing a promising approach against NM-induced pulmonary fibrosis.
Evolutionary and Predictive Functional Insights into the Aquaporin Gene Family in the Allotetraploid Plant Nicotiana tabacum
Authors: Ahmed Jahed , Mercx Sébastien , Boutry Marc , Chaumont François
Published: July 2020

Aquaporins (AQPs) are a class of integral membrane proteins that facilitate the membrane diffusion of water and other small solutes. Nicotiana tabacum is an important model plant, and its allotetraploid genome has recently been released, providing us with the opportunity to analyze the AQP gene family and its evolution. A total of 88 full-length AQP genes were identified in the N. tabacum genome, and the encoding proteins were assigned into five subfamilies: 34 plasma membrane intrinsic proteins (PIPs); 27 tonoplast intrinsic proteins (TIPs); 20 nodulin26-like intrinsic proteins (NIPs); 3 small basic intrinsic proteins (SIPs); 4 uncharacterized X intrinsic proteins (XIPs), including two splice variants. We also analyzed the genomes of two N. tabacum ancestors, Nicotiana tomentosiformis and Nicotiana sylvestris, and identified 49 AQP genes in each species. Functional prediction, based on the substrate specificity-determining positions (SDPs), revealed significant differences in substrate specificity among the AQP subfamilies. Analysis of the organ-specific AQP expression levels in the N. tabacum plant and RNA-seq data of N. tabacum bright yellow-2 suspension cells indicated that many AQPs are simultaneously expressed, but differentially, according to the organs or the cells. Altogether, these data constitute an important resource for future investigations of the molecular, evolutionary, and physiological functions of AQPs in N. tabacum.
Looking Back to Lower-Level Information in Few-Shot Learning
Authors: Yu Zhongjie , Raschka Sebastian
Published: July 2020

Humans are capable of learning new concepts from small numbers of examples. In contrast, supervised deep learning models usually lack the ability to extract reliable predictive rules from limited data scenarios when attempting to classify new examples. This challenging scenario is commonly known as few-shot learning. Few-shot learning has garnered increased attention in recent years due to its significance for many real-world problems. Recently, new methods relying on meta-learning paradigms combined with graph-based structures, which model the relationship between examples, have shown promising results on a variety of few-shot classification tasks. However, existing work on few-shot learning is only focused on the feature embeddings produced by the last layer of the neural network. The novel contribution of this paper is the utilization of lower-level information to improve the meta-learner performance in few-shot learning. In particular, we propose the Looking-Back method, which could use lower-level information to construct additional graphs for label propagation in limited data settings. Our experiments on two popular few-shot learning datasets, miniImageNet and tieredImageNet, show that our method can utilize the lower-level information in the network to improve state-of-the-art classification performance.
Open-Source Grinding Machine for Compression Screw Manufacturing
Authors: Franz Jacob , Pearce Joshua M.
Published: July 2020

Some of the most promising distributed recycling and additive manufacturing (DRAM) technical systems use fused particle fabrication (FPF) or fused granular fabrication (FGF), where compression screws force post-consumer waste plastic through a heated nozzle for direct 3D printing. To assist the technical evolution of these systems, this study provided the details of an invention for a low-cost, easily replicable open-source grinding machine for compression screw manufacturing. The system itself can be largely fabricated using FPF/FGF following the self-replicating rapid prototyper (RepRap) methodology. This grinding machine can be made from a cordless cut-off grinder and < $155 in parts. The new invention is demonstrated to be able to cut custom screws with variable (i) channel depths, (ii) screw diameters, (iii) screw lengths, (iv) pitches, (v) abrasive disk thicknesses, (vi) handedness of the screws, (vii) and materials (three types of steel tested: 1045 steel, 1144 steel, and 416 stainless steel). The results show that the device is more than capable of replicating commercial screws as well as providing makers with a much greater flexibility to make custom screws. This invention enables the DRAM toolchain to become even more self-sufficient, which assists the goals of the circular economy.