bluuebunny/crossref_metadata_2025 huggingface dataset:
A tutoria na educação à distância em tempos de COVID-19: orientações relevantes
Authors: Camacho Alessandra Conceição Leite Funchal , Joaquim Fabiana Lopes , Menezes Harlon França de , Sant’ Anna Rosana Moreira
Published: March 2020

Este trabalho tem como objetivo analisar a tutoria na Educação à Distância (EAD) em tempos de COVID-19. Trata-se de um descritivo de revisão de literatura, de natureza qualitativa sobre a tutoria na educação à distância em tempos de COVID-19 com orientações relevantes para os professores/tutores em EAD diante das recomendações do Ministério da Educação. Está fundamentado em uma revisão de literatura narrativa com discussão dos seguintes pontos: a interatividade como proposta pedagógica e as competências do tutor com vistas à aprendizagem cooperativa na Educação à Distância. Os professores/tutores que atuam em cursos e disciplinas online devem ser mediadores dos conteúdos desenvolvidos levando em consideração os conteúdos de multimídia, o espaço colaborativo, a flexibilidade e acessibilidade. Diante desta realidade sobre a Pandemia do COVID-19 recomenda-se professor/tutor traga intervenções significativas que promovam a assimilação das informações, de modo que cada indivíduo, usufruindo dos recursos disponíveis em EAD, possa compor cenários em sintonia com os elementos próprios de seu contexto e consiga transformar seu universo intelectual com experiências positivas de aprendizagem.
Crystallized jabuticaba peel: a novel strategy for by-product industrialization
Authors: Garcia Lismaíra Gonçalves Caixeta , Vendruscolo Francielo , Silva Flávio Alves da , Asquieri Eduardo Ramirez , Damiani Clarissa
Published: March 2020

The aim of this work was the integral application of jabuticaba peel to obtaining a crystallized jabuticaba peel by osmotic dehydration, crystallization and convective drying at different temperatures. Every two months for a year, the product was subjected to determinations of anthocyanins, phenolic compounds, antioxidant capacity, physicochemical characteristics and determination of color. The color measurements and bioactive compounds determinations were significantly influenced by the interaction between the factors drying temperature and storage time. The proximal composition was not affected by drying temperature, whereas total soluble solids, pH, titratable acidity and water activity showed significant differences. Crystallized jabuticaba peel is a low cost product and viable alternative to minimize the large losses during the harvest season.
Water budget changes in the Amazon basin under RCP 8.5 and deforestation scenarios
Authors: Gomes WB , Correia FWS , Capistrano V , Veiga JAP , Vergasta LA , Chou SC , Lyra AA , Nobre P , Rocha VM
Published: March 2020

We used climate models to assess the effects of 2 distinct anthropogenic forcings on the water budget in the Amazon basin: (1) increasing global greenhouse gases under the RCP8.5 scenario, and (2) land cover change caused by deforestation. The Eta regional climate model, driven by the Brazilian Earth System Model version 2.5 (BESM 2.5), was used to simulate the climate response under the RCP8.5 scenario and due to deforestation throughout the 21st century. Changes in energy and water budgets led to an increase in temperature that reached 5°C throughout the basin. In the RCP8.5 scenario, moisture convergence, precipitation and evapotranspiration all decreased. In this scenario, the positive feedback mechanism was predominant, as the reductions in evapotranspiration and moisture convergence acted in the same direction to reduce precipitation. In the future deforestation scenarios, reductions in precipitation were even stronger. In this case, the negative feedback mechanism predominated, in which the relative reduction in evapotranspiration was greater than the reduction in precipitation, leading to an increase in moisture convergence over the region. Changes in temperature and the water cycle were intensified in the future deforestation scenarios. These results show that the 2 anthropogenic factors can change the water budget and cause an imbalance in the climate-biome system in the Amazon basin, highlighting the need for public conservation policies to halt the increase in environmental degradation in the Amazon basin and to reduce greenhouse gases emissions due the burning of fossil fuels.
When sharks are away, rays will play: effects of top predator removal in coral reef ecosystems
Authors: Sherman CS , Heupel MR , Moore SK , Chin A , Simpfendorfer CA
Published: March 2020

Shark abundances are decreasing on many coral reefs, but the ecosystem effects of this loss are poorly understood. Rays are a prevalent mesopredator in tropical coral reef ecosystems that are preyed upon by top predators like sharks. Studies have suggested reduced predator abundances lead to increases in mesopredator abundance (mesopredator release). We examined the relationship between top predator abundances and the abundance and behaviour of 2 small benthic ray genera using baited remote underwater video systems (BRUVS) across 6 countries. Where predators were more abundant, 2 genera of small benthic rays were sighted less often, possibly because of lower abundances. Small ray behaviour was also significantly affected by predator abundance. Individuals of focal ray species visited BRUVS significantly fewer times at sites with higher predator abundances. Where predators were less abundant, rays spent significantly more time in the video frame, and were more likely to feed from bait bags. In addition to predator abundance, small ray presence was significantly influenced by reef relief and depth. Neotrygon spp. were more abundant on deeper, lower relief habitats, while Taeniura spp. were more prevalent in reef-associated shallow, high relief habitats. Overall, this study found that predator abundance had a significant effect on small benthic ray abundance and behaviour in the presence of BRUVS. Results demonstrate that changes in both abundance and behaviour associated with predator loss may make the interpretation of phenomenon like mesopredator release more difficult to identify unless behavioural effects are considered.
Investigation of atomically thin films: state of the art
Authors: Larionov K V , Sorokin P B
Published: March 2020

The review is devoted to the current state of research in one of the topical areas of the physics and chemistry of two-dimensional materials — the study of atomically thin films. The structure and properties of atomically thin monoelemental films, such as 2D iron, gold, and lithium, as well as silicene, germanene, borophene, etc., are described in detail. Two-dimensional films of metallic compounds like iron, copper, and zinc oxides and iron, cobalt, and copper carbides are considered. The main approaches to the stabilization of monoatomic films inside pores or between layers of other 2D materials are presented, and the exfoliation mechanism of ionic-covalent films with a polar surface into weakly bounded monolayers is described.
ω – SUBSEMIRING FUZZY
Authors: Abdurrahman Saman
Published: March 2020

Mapping ρ is called a fuzzy subset of an empty set of S if ρ is the mapping from S to the closed interval [0,1]. A fuzzy subset ρ introduced into this paper is a fuzzy subset of semiring S, defined byρ(a+d)≥ρ(a)∧ρ(d) and ρ(ad)≥ρ(a)∧ρ(d),for each a,d∈S so that a fuzzy subset ρ is called a fuzzy subsemiring from a semiring S.In this paper, Investigated the basic nature of subsemi-ring fuzzy ρ from a semiring S, which includes intersecting with two or more fuzzy subsemiring from a semiring S, is always a fuzzy subsemiring from a semiring S. Moreover, it was introduced to the concept of ω – fuzzy subsemiring from a semiring S which is denoted by ρω. Finally, investigated the minimal conditions that guarantee the existence of ω – fuzzy subsemiring ρω and the intersection of two or more ω – fuzzy subsemiring ρω of a semiring, S is always an ω – fuzzy subsemiring ρω of a semiring S.

Pemetaan  disebut subset fuzzy dari himpunan tidak kosong  jika merupakan pemetaan dari  ke interval tutup . Subset fuzzy  yang diibahas pada paper ini adalah subset fuzzy dari semiring , yang memenuhi kondisi

 dan ,

untuk setiap sedemikian sehingga subset fuzzy  disebut subsemiring fuzzy dari semiring . Pada paper ini, diselidiki sifat dasar dari subsemiring fuzzy  dari semiring , yang meliputi irisan antara dua atau lebih subsemiring fuzzy dari semiring  selalu merupakan subsemiring fuzzy dari semiring . Selain itu, pada paper ini diperkenalkan konsep  – subsemiring fuzzy dari semiring , yang dinotasikan dengan . Akhirnya, diselidiki kondisi minimal yang menjamin eksistensi dari  – subsemiring fuzzy , dan irisan dua atau lebih  – subsemiring fuzzy  dari semiring  selalu merupakan  – subsemiring fuzzy  dari semiring .
Higiene Sanitasi dan Kejadian Infeksi Kecacingan pada Siswa Sekolah Dasar
Authors: Sidabutar Sondang
Published: March 2020

Background: Higiene sanitation is a factor that is closely related to Helminthiases infection. Purpose: this study was to determine how the occurrence of sanitary hygiene with helminthiases infection in the District elementary school students 0913152014 in District Raya Simalungun. Method: The type of research was descriptive analytic with cross sectional approach. The population in this study were students of class I to class VI (91 people). The sampling technique was simple random sampling (48). The instrument used in this study was a laboratory test and a questionnaire. The data obtained in this study were analyzed using Chi-square test. Result: Based on Chi-square analysis of the relationship between hygiene and sanitation with the incidence of intestinal worms found handwashing (X2 = 23), the habit of cutting the nails (X2 = 8.21), the habit of eating raw foods (X2 = 12.24), latrine ownership (X2 = 11:47), type of flooring (X2 = 6.13), and the availability of clean water (X2 = 0.0276). Conclusion: From the results of research and discussion, it could be concluded that there was a correlation with the incidence of worm infection habit of hand washing, nail cutting habit, the habit of eating raw foods, floor of the house and latrine ownership.

Keywords: sanitation; hygiene; helminthiases; elementary students

ABSTRAK

Latarbelakang: Higiene sanitasi merupakan faktor yang sangat erat dengan infeksi kecacingan.Tujuan: Tujuan penelitian adalah mengetahui bagaimana higiene sanitasi dengan kejadian infeksi kecacingan pada siswa Sekolah Dasar 091315 Kecamatan Raya Kabupaten Simalungun. Metode: Jenis penelitian ini adalah dekriptif analitik dengan pendekatan cross sectional. Populasi adalah siswa kelas I sampai kelas VI (91 orang). Teknik pengambilan sampel adalah simple random sampling (48). Instrumen yang digunakan adalah uji laboratorium dan kuesioner. Data yang diperoleh, dianalisis menggunakan rumus statistik uji Chi-square dengan t hitung (α = 0,05). Hasil: Berdasarkan analisis Chi-square hubungan antara higiene sanitasi dengan kejadian penyakit cacingan didapatkan kebiasaan mencuci tangan ( X2=23), kebiasaan memotong kuku (X2=8,21), kebiasaan mengkonsumsi makanan mentah (X2=12,24), kepemilikan jamban (X2=11.47), jenis lantai (X2=6.13), dan ketersediaan air bersih (X2=0.0276). Kesimpulan: ada hubungan kejadian infeksi kecacingan dengan kebiasaan mencuci tangan, kebiasaan memotong kuku, kebiasaan mengkonsumsi makanan mentah, lantai rumah dan kepemilikan jamban.

Kata kunci: higiene; sanitasi; kecacingan; siswa SD
Effects of Exogenous Spermidine on Root Metabolism of Cucumber Seedlings under Salt Stress by GC-MS
Authors: Liu Bing , Peng Xujian , Han Lingjuan , Hou Leiping , Li Bin
Published: March 2020

To investigate the effects of exogenous spermidine (Spd) on metabolism changes under salt stress in cucumber roots, a gas chromatography-mass spectrometry (GC-MS) was performed. The results showed that most of the 142 metabolites responded to salt stress or exogenous Spd treatment. Salt stress reduced carbon consumption, resulted in the transformation of glycolysis and the tricarboxylic acid (TCA) cycle to the pentose phosphate pathway (PPP), and meanwhile increased salicylic acid (SA) and ethylene synthesis, and, thus, inhibited the growth of seedlings. However, exogenous Spd further improved the utilization of carbon, the energy-saving pattern of amino acid accumulation, and the control of hydroxyl radicals. In conclusion, Spd could promote energy metabolism and inhibit SA and ethylene synthesis in favor of root growth that contributes to higher salt tolerance. This study provides insight that may facilitate a better understanding of the salt resistance by Spd in cucumber seedlings.
Frost Risk Management in Chickpea Using a Modelling Approach
Authors: Chauhan Yashvir S. , Ryan Merrill
Published: March 2020

Post-flowering frosts cause appreciable losses to the Australian chickpea industry. The Northern Grains Region (NGR) of Australia, which accounts for nearly 95% of chickpea production in Australia, is frequently subjected to such events. The objective of this study was to map frost risk in chickpea in the NGR and develop strategies to minimise the impacts of such risk. The Agricultural Production System Simulator (APSIM) modelling framework was used to determine spatial and temporal trends in post-flowering frost risk. The NGR could be divided into six broad sub-regions, each delineating locations with similar frost risk. The risk was nearly two to three times greater in the Southern Downs and Darling Downs sub-regions as compared to the Central Queensland Highlands, Dawson Callide, New South Wales, and Northern New South Wales–Western Downs sub-regions. There was an increasing trend in the frequency of frost events in the Southern Downs and New South Wales sub-regions, and a decreasing trend in the Central Queensland Highlands and Dawson Callide sub-regions, consistent with the changing climate of the NGR. In each sub-region, frost risk declined with delayed sowings, but such sowings resulted in simulation of reduced water limited yield potential (unfrosted) as well. The model output was also used to compute 10, 30, 50, and 70% probabilities of the last day of experiencing −3 to 2 °C minimum temperatures and identify the earliest possible sowings that would avoid such temperatures after flowering. Choosing the earliest sowing times with a 30% frost risk could help increase overall yields in environments with high frost risk. Simulations involving genotype x environment x management interactions suggested additional opportunities to minimise frost losses through the adoption of particular cultivars of differing phenology and the use of different agronomy in various environments of the NGR. The study indicates that there is considerable variation in frost risk across the NGR and that manipulating flowering times either through time of sowing or cultivar choice could assist in minimising yield losses in chickpea due to frost.
Integrated Weed Management in Herbaceous Field Crops
Authors: Scavo Aurelio , Mauromicale Giovanni
Published: March 2020

Current awareness about the environmental impact of intensive agriculture, mainly pesticides and herbicides, has driven the research community and the government institutions to program and develop new eco-friendly agronomic practices for pest control. In this scenario, integrated pest management and integrated weed management (IWM) have become mandatory. Weeds are commonly recognized as the most important biotic factor affecting crop production, especially in organic farming and low-input agriculture. In herbaceous field crops, comprising a wide diversity of plant species playing a significant economic importance, a compendium of the specific IWM systems is missing, that, on the contrary, have been developed for single species. The main goal of this review is to fill such gap by discussing the general principles and basic aspects of IWM to develop the most appropriate strategy for herbaceous field crops. In particular, a 4-step approach is proposed: (i) prevention, based on the management of the soil seedbank and the improvement of the crop competitiveness against weeds, (ii) weed mapping, aiming at knowing the biological and ecological characteristics of weeds present in the field, (iii) the decision-making process on the basis of the critical period of weed control and weed thresholds and iv) direct control (mechanical, physical, biological and chemical). Moreover, the last paragraph discusses and suggests possible integrations of allelopathic mechanisms in IWM systems.
Performance of a Set of Eggplant (Solanum melongena) Lines With Introgressions From Its Wild Relative S. incanum Under Open Field and Screenhouse Conditions and Detection of QTLs
Authors: Mangino Giulio , Plazas Mariola , Vilanova Santiago , Prohens Jaime , Gramazio Pietro
Published: March 2020

Introgression lines (ILs) of eggplant (Solanum melongena) represent a resource of high value for breeding and the genetic analysis of important traits. We have conducted a phenotypic evaluation in two environments (open field and screenhouse) of 16 ILs from the first set of eggplant ILs developed so far. Each of the ILs carries a single marker-defined chromosomal segment from the wild eggplant relative S. incanum (accession MM577) in the genetic background of S. melongena (accession AN-S-26). Seventeen agronomic traits were scored to test the performance of ILs compared to the recurrent parent and of identifying QTLs for the investigated traits. Significant morphological differences were found between parents, and the hybrid was heterotic for vigour-related traits. Despite the presence of large introgressed fragments from a wild exotic parent, individual ILs did not display differences with respect to the recipient parent for most traits, although significant genotype × environment interaction (G × E ) was detected for most traits. Heritability values for the agronomic traits were generally low to moderate. A total of ten stable QTLs scattered across seven chromosomes was detected. For five QTLs, the S. incanum introgression was associated with higher mean values for plant- and flower-related traits, including vigour prickliness and stigma length. For one flower- and four fruit-related-trait QTLs, including flower peduncle and fruit pedicel lengths and fruit weight, the S. incanum introgression was associated with lower mean values for fruit-related traits. Evidence of synteny to other previously reported in eggplant populations was found for three of the fruit-related QTLs. The other seven stable QTLs are new, demonstrating that eggplant ILs are of great interest for eggplant breeding under different environments.
Single Blinded Study on the Feasibility of Decontaminating LA-MRSA in Pig Compartments under Routine Conditions
Authors: Kobusch Iris , Müller Hannah , Mellmann Alexander , Köck Robin , Boelhauve Marc
Published: March 2020

In countries with intensive pig husbandry in stables, the prevalence of livestock-associated (LA) methicillin-resistant Staphylococcus aureus (MRSA) on such farms has remained high in the last few years or has also further increased. Simple measures to reduce the LA-MRSA among pigs have not yet been successfully implemented. Earlier publications showed a decontamination of LA-MRSA was only possible with great effort. The aim of this study is to determine the suitability of routine cleaning and disinfection (C&D) for adequate LA-MRSA decontamination. For this purpose, at least 115 locations in a piglet-rearing compartment were examined before and after cleaning and disinfection. The sample locations were stratified according to accessibility for pigs and the difficulty of cleaning. The cleaning work was carried out routinely by farm employees, who were not informed about the sampling (single blinded). While before cleaning and disinfection, 85% of the samples from the surfaces were LA-MRSA positive, while only 2% were positive thereafter. All LA-MRSA-positive samples after cleaning and disinfection were outside the animal area. Air samples also showed no LA-MRSA after cleaning and disinfection. Conclusion: In well-managed livestock farms, decontamination of the LA-MRSA barn is quite possible; after C&D no LA-MRSA was detectable at animal height.
Flight Strategy Optimization for High-Altitude Solar-Powered Aircraft Based on Gravity Energy Reserving and Mission Altitude
Authors: Sun Mou , Ji Xinzhe , Sun Kangwen , Zhu Ming
Published: March 2020

High-altitude long-duration (HALE) flight capability is one of the ultimate goals pursued by human aviation technology, and the high-altitude solar-powered aircraft (SPA) is the most promising technical approach to achieve this target as well as wide application prospects. Due to the particularity of the energy system, the flight strategy optimization through the storage of gravity potential energy and other methods is a significant way to enhance the flight and application abilities for the SPA. In this study, a flight strategy optimization model has been proposed for the aim of HALE flight capability, which is based on the gravity energy reserving and mission altitude in practical engineering applications. This integrated model contains the five flight path phase model, the three-dimensional kinematic model, aerodynamic model, solar irradiation model and energy store and loss model. To solve the optimization problem of three-dimensional flight strategy, the Gauss pseudo-spectral Method (GPM) was employed to establish and calculate the optimal target as its advantages in treating process constraints and terminal constraints for the multiphase optimization problem. At last, the flight trajectory optimization with minimal battery mass for Zephyr 7 was studied by the GPOPS with some function files in MATLAB. The results indicate that the Zephyr 7 can reduce the battery mass from 16 kg to 12.61 kg for the day and night cycle flight and missions, which equals to increasing the battery specific energy by 23.1%. Meanwhile, the optimization results also show that the attitude angel may contribute to increasing the energy gained by photovoltaic cells. In addition, this optimized flight strategy brings the possibility of monthly or annual continuous flight for SPA as the simulation date is set to the autumnal day.
Oral Health Status of Children with Autism in Central Italy
Authors: Bossù Maurizio , Trottini Mario , Corridore Denise , Di Giorgio Gianni , Sfasciotti Gian Luca , Palaia Gaspare , Ottolenghi Livia , Polimeni Antonella , Di Carlo Stefano
Published: March 2020

Children with autism spectrum disorder (ASD) have significantly higher prevalence and caries severity compared to the average population. Knowledge about the oral health indices of children with this mental disorder is key to designing efficient plans of intervention. This paper reports the results of a study on the oral health status of children with ASD in central Italy. This is the first study of this type in Italy. The sample consists of 229 autistic children aged between 5 and 14 years, attending the Unit of Special Needs Policlinico Umberto I in Rome. Each patient received an intraoral examination to investigate decayed, missing, and filled teeth as well as periodontal status. Information on demographic attributes, dietary habits, medical history, and child’s cooperativeness at the first visit was also recorded. Of the participants, 79.26% presented signs of gingivitis and about 90% of them had plaque. Caries prevalence was 66.38%. The average of the total number of decayed, missing, and filled teeth in the permanent and primary dentition was 2.91. Among the factors considered, only dietary habits and the periodontal indices showed statistically significant association with caries prevalence and caries severity. Despite the selection bias, that prevents us to interpret the results presented as epidemiological evidence, our study suggests that children with ASD in central Italy represent a population at risk.
An Enhanced Auxiliary Information-Based EWMA-t Chart for Monitoring the Process Mean
Authors: Chen Jen-Hsiang , Lu Shin-Li
Published: March 2020

The exponentially weighted moving average t chart using auxiliary information (AIB-EWMA-t chart) is an effective approach for monitoring small process mean shifts when the process standard deviation is unstable or poorly estimated. To further enhance the sensitivity of the AIB-EWMA-t chart, in this study, we propose an AIB generally weighted moving average (GWMA) t chart (AIB-GWMA-t chart) to monitor the process mean. The existing EWMA-t, GWMA-t, and AIB-EWMA-t charts are special cases of the AIB-GWMA-t chart. Numerical simulation studies indicate that the AIB-GWMA-t chart performs uniformly and substantially better than the EWMA-t and GWMA-t charts in terms of average run length. Moreover, the AIB-GWMA-t chart with large design and adjustment parameters also outperforms the AIB-EWMA-t chart when the correlation coefficients are within a certain range. An illustrative example is provided to highlight the efficiency of the proposed AIB-GWMA-t chart in detecting small process mean shifts.
Simulation of Mining-Induced Ground Damage Using Orthogonal Experiments to Determine Key Parameters of Super-Large Coalface: A Case Study in Shendong Coalfield in China
Authors: Cai Yinfei , Li Xiaojing , Xiao Wu , Zhang Wenkai
Published: March 2020

High-strength mining of super-large coalfaces in the Shendong coalfield causes significant damage to the ground surface. To study the key parameters of undermined coalfaces that affect ground damage, 25 numerical simulation models were designed using an orthogonal experimental method based on the geological and mining conditions of the Bulianta Mine. In the orthogonal design, four factors (the lengths in both the dip and strike directions, the thickness and the mining speed of the coalface) were considered, with five levels designed for each factor. The subsidence displacements and deformations caused by the excavation were then simulated and verified using field surveying data. A damage extent index (DEI) was introduced and used to assess the extent of global ground damage caused by each simulative excavation. Analysis of variance (ANOVA) method was then employed to determine the key parameters of the coalface that significantly influence the ground damage. It was found that the coalface dip length and thickness and the coalface thickness can be regarded as the key parameters for ground objects of building and timberland, respectively. This research provides theoretical and technical support for the coordinated exploitation of resources and environments in Shendong and other similar, ecologically fragile coalfields.
Detecting and Solving Tube Entanglement in Bin Picking Operations
Authors: Leão Gonçalo , Costa Carlos M. , Sousa Armando , Veiga Germano
Published: March 2020

Manufacturing and production industries are increasingly turning to robots to carry out repetitive picking operations in an efficient manner. This paper focuses on tackling the novel challenge of automating the bin picking process for entangled objects, for which there is very little research. The chosen case study are sets of freely curved tubes, which are prone to occlusions and entanglement. The proposed algorithm builds a representation of the tubes as an ordered list of cylinders and joints using a point cloud acquired by a 3D scanner. This representation enables the detection of occlusions in the tubes. The solution also performs grasp planning and motion planning, by evaluating post-grasp trajectories via simulation using Gazebo and the ODE physics engine. A force/torque sensor is used to determine how many items were picked by a robot gripper and in which direction it should rotate to solve cases of entanglement. Real-life experiments with sets of PVC tubes and rubber radiator hoses showed that the robot was able to pick a single tube on the first try with success rates of 99% and 93%, respectively. This study indicates that using simulation for motion planning is a promising solution to deal with entangled objects.
Development of Bionanocomposites Based on PLA, Collagen and AgNPs and Characterization of Their Stability and In Vitro Biocompatibility
Authors: Râpă Maria , Stefan Laura Mihaela , Zaharescu Traian , Seciu Ana-Maria , Țurcanu Anca Andreea , Matei Ecaterina , Predescu Andra Mihaela , Antoniac Iulian , Predescu Cristian
Published: March 2020

Bionanocomposites including poly(lactic acid) (PLA), collagen, and silver nanoparticles (AgNPs) were prepared as biocompatible and stable films. Thermal properties of the PLA-based bionanocomposites indicated an increase in the crystallinity of PLA plasticized due to a small quantity of AgNPs. The results on the stability study indicate the promising contribution of the AgNPs on the durability of PLA-based bionanocomposites. In vitro biocompatibility conducted on the mouse fibroblast cell line NCTC, clone 929, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay showed high values of cell viability (>80%) after cell cultivation in the presence of bionanocomposite formulations for 48 h, while the percentages of lactate dehydrogenase (LDH) released in the culture medium were reduced (<15%), indicating no damages of the cell membranes. In addition, cell cycle analysis assessed by flow cytometry indicated that all tested bionanocomposites did not affect cell proliferation and maintained the normal growth rate of cells. The obtained results recommend the potential use of PLA-based bionanocomposites for biomedical coatings.
Minimum-Variance Control System with Variable Control Penalty Factor
Authors: Filip Ioan , Dragan Florin , Szeidert Iosif , Albu Adriana
Published: March 2020

The present paper proposes (as the main contribution) an additional self-tuning mechanism for an adaptive minimum-variance control system, whose main goal is to extend its functionality for a large value range of unmeasurable perturbations which disturb the controlled process. Through the standard design procedure, a minimum variance controller uses by default an internal self-tuning mechanism based on the process parameter estimates. However, the main parameter which overwhelmingly influences the control performance is the control penalty factor ( ρ ) . This parameter weights the term that describes the control variance in a criterion function whose minimization is the starting point of the control law design. The classical minimum-variance control involves an off-line tuning of this parameter, its value being set as constant throughout the entire operating regime. Based on the measurement of the process output error, the contribution of the proposed strategy consists in a real-time tuning of the control penalty factor, to ensure the stability of the control system, even under conditions of high disturbances. The proposed tuning mechanism adjusts this parameter by implementing a bipositional switching strategy based on a sharp hysteresis loop. Therefore, instead of the standard solution that involves a constant value of the control penalty factor ρ (a priori computed and set), this paper proposes a dual value for this controller parameter. The main objective is to allow the controlled process to operate in a stable fashion even in more strongly disturbed regimes (regimes where the control system becomes unstable and is usually switched off for safety reasons). To validate the proposed strategy, an induction generator integrated into a wind energy conversion system was considered as controlled plant. Operating under the action of strong disturbances (wind gusts, electrical load variations), the extension of safe operating range (thus avoiding the system disengagement) is an important goal of such a control system.
The Systematic Design of Industrial Products through Design Archetypes: An Application on Mechanical Transmissions
Authors: Vergnano Alberto , Gherardini Francesco , Leali Francesco
Published: March 2020

Engineering design is a knowledge intensive activity for both new and mature technical systems, such as mechanical transmissions. However, design knowledge is often transferred with conservative and unstructured approaches, although knowledge management would be of the utmost importance for modern industries. In this work, we introduce a design tool, called design archetype, for collecting and managing knowledge in systematic design processes. The design archetype addresses input design requirements for different design concepts, therefore, improving awareness of the design process by interactively modifying the design solution due to different input requirements. Finally, the design archetype updates the parameters of a first embodiment computer-aided design model of the concept. A method for the development of design archetypes is presented and applied to two case studies of mechanical transmission subassemblies. The results demonstrate the effectiveness of a systematic design method based on design archetypes stored in the company database.
Flexural Vibration Analysis of Nuclear Fuel Rod Bundles Interacting with Surrounding Fluid Subjected to Pressure Wave
Authors: Yang Wonseok , Kang Heungseok , Park Junhong
Published: March 2020

The structural behavior of the nuclear rod bundles that consisted of cylindrical beams was predicted using the spectral element method (SEM) while considering the interaction with the surrounding fluid. Viscous fluid behavior was utilized in order to calculate the forces acting on the nuclear rod bundles from the incident pressure waves. The added mass and fluid coupling on the nuclear rod bundles were determined for the position patterns and gaps of each of the cylindrical beams. The pressure field from propagating waves in the surrounding fluid was calculated with respect to the boundary conditions of the surface of the vibrating structures. With the increasing number of nuclear rods and decreasing pressure wavelengths, the structural vibration of the nuclear rod bundles that were induced by the propagating forces affected the scattering events of the pressure field. The frequency response of the nuclear rod bundles from the pressure waves in the water exhibited smaller damping, because the incident pressure wave travels without fluid coupling due to the longer wavelength when compared with distance between rods. The proposed numerical method can be utilized for the detailed design for effective parameters of a supporting system to reduce the vibration of nuclear fuel rod bundles for safety control.
Aerosol Optical Properties and Contribution to Differentiate Haze and Haze-Free Weather in Wuhan City
Authors: Zhang Miao , Liu Jing , Bilal Muhammad , Zhang Chun , Nazeer Majid , Atique Luqman , Han Ge , Gong Wei
Published: March 2020

Haze is an atmospheric phenomenon in which different types of particulates obscure the sky, and hence affect almost all human activities. Over a couple of recent decades, China has witnessed increasingly worse air quality as well as atmospheric haziness in its cities. There are various haze contributing factors including the rapid industrialization, excessive biomass burning, and an increase in the number of vehicles. This study proposes a methodology based on the aerosols scattering and absorption properties, to predict the likelihood of an episode of hazy days. This case study employs the aerosol optical properties data from integrated nephelometer and aethalometer sensors from December 2009 to September 2014 over Wuhan. The role and contribution of each aerosol optical parameter (e.g., aerosol scattering and absorption coefficients, single scattering albedo, scattering, and absorption Ångström exponents, backscatter ratio, and asymmetry factor) in distinguishing haze and haze-free conditions has been quantitatively determined based on a machine learning approach. Each aerosol optical parameter was classified independently by the support vector machine (SVM) algorithm, and the aerosol scattering (85.37%) and absorption (74.53%) coefficients were found to be primary potential indicators. Through the Kolmogorov-Smirnov test and traditional statistical analysis, the aerosol scattering and absorption coefficients were then verified as important indicators in distinguishing haze and haze-free days. Finally, through a probability density diagram and frequency histogram, we propose a simple quantitative standard to distinguish between haze and haze-free conditions based on the aerosol scattering coefficient and absorption coefficient in Wuhan City. The accuracy of the standard was determined to be 81.49% after testing, which indicates an accurate result. An error in aerosol optical properties may lead to an error in the calculation of aerosol radiative forcing, the earth’s energy budget, and climate prediction. Therefore, understanding of the aerosol properties during haze-free and haze-days will help policymakers to make new policies to control urban pollution and their effects on human health.
Advanced Ultraviolet Radiation and Ozone Retrieval for Applications—Surface Ultraviolet Radiation Products
Authors: Lipponen Antti , Ceccherini Simone , Cortesi Ugo , Gai Marco , Keppens Arno , Masini Andrea , Simeone Emilio , Tirelli Cecilia , Arola Antti
Published: March 2020

AURORA (Advanced Ultraviolet Radiation and Ozone Retrieval for Applications) is a three-year project supported by the European Union in the frame of its H2020 Call (EO-2-2015) for “Stimulating wider research use of Copernicus Sentinel Data”. The project addresses key scientific issues relevant for synergistic exploitation of data acquired in different spectral ranges by different instruments on board the atmospheric Sentinels. A novel approach, based on the assimilation of geosynchronous equatorial orbit (GEO) and low Earth orbit (LEO) fused products by application of an innovative algorithm to Sentinel-4 (S-4) and Sentinel-5 (S-5) synthetic data, is adopted to assess the quality of the unique ozone vertical profile obtained in a context simulating the operational environment. The first priority is then attributed to the lower atmosphere with calculation of tropospheric columns and ultraviolet (UV) surface radiation from the resulting ozone vertical distribution. Here we provide details on the surface UV algorithm of AURORA. Both UV index (UVI) and UV-A irradiance are provided from synthetic satellite measurements, which in turn are based on atmospheric scenarios from MERRA-2 (Modern-Era Retrospective analysis for Research and Applications, Version 2) re-analysis. The UV algorithm is implemented in a software tool integrated in the technological infrastructure developed in the context of AURORA for the management of the synthetic data and for supporting the data processing. This was closely linked to the application-oriented activities of the project, aimed to improve the performance and functionality of a downstream application for personal UV dosimetry based on satellite data. The use of synthetic measurements from MERRA-2 gives us also a “ground truth”, against which to evaluate the performance of our UV model with varying inputs. In this study we both describe the UV algorithm itself and assess the influence that changes in ozone profiles, due to the fusion and assimilation, can cause in surface UV levels.
The Inoculation of Probiotics In Vivo Is a Challenge: Strategies to Improve Their Survival, to Avoid Unpleasant Changes, or to Enhance Their Performances in Beverages
Authors: Speranza Barbara , Campaniello Daniela , Petruzzi Leonardo , Altieri Clelia , Sinigaglia Milena , Bevilacqua Antonio , Rosaria Corbo Maria
Published: March 2020

The inoculation of probiotics in beverages (probiotication) requires special technologies, as probiotic microorganisms can experience stress during food processing (acid, cold, drying, starvation, oxidative, and osmotic stresses) and gastrointestinal transit. Survival to harsh conditions is an essential prerequisite for probiotic bacteria before reaching the target site where they can exert their health promoting effects, but several probiotics show a poor resistance to technological processes, limiting their use to a restricted number of food products. Therefore, this paper offers a short overview of the ways to improve bacterial resistance: by inducing a phenotypic modification (adaptation) or by surrounding bacteria through a physical protection (microencapsulation). A second topic briefly addressed is genetic manipulation, while the last section addresses the control of metabolism by attenuation through physical treatments to design new kinds of food.
The Lymphoscintigraphic Study of Unpredictable Head and Neck Cutaneous Melanoma Lymphatic Drainage
Authors: Lavelli Valentina , Ferrari Cristina , Santo Giulia , Altini Corinna , Ballini Andrea , Sardaro Angela , Fanelli Margherita , Pisani Antonio Rosario , Nappi Anna Giulia , Giudice Giuseppe , Rubini Giuseppe
Published: March 2020

Head and neck cutaneous melanoma (HNCM) does not always follow standard lymphatic drainage; typical expected lymphatic pathways are associated with unexpected ones. The aim of this study was to investigate the relation between the primary HNCM sites and all possible lymphatic drainage pathways by lymphoscintigraphy with a special focus on the unexpected sentinel lymph node (SLNs) detection. We retrospectively analyzed 67 patients (46 M, 21 F; mean age 63 years) who underwent lymphoscintigraphy from January 2004 to November 2018. 99mTc-serum albumin was injected intra-dermally at the dose of 18–37 MBq in 0.2–0.4 mL. All patients underwent dynamic and static image acquisition. For all patients, the relation between the expected and unexpected SLNs was performed using the “Sidney Melanoma Unit Database” as our reference. The relation was performed also according to the primary HNCM localization. Cohens’ kappa was calculated. In 61/67 (91%) of patients, SLNs were detected only in predictable sites, while in six/67 (9%), unexpected SLNs were revealed. In all patients, the agreement proportion was 91% (95% confidence interval CI 0.8–0.96) and Cohen’s K was 0.11 (95% CI 0–0.43). Regarding the primary melanoma sites, the nasolabial field HNCM showed the highest rate of concordance (K = 0.60; 95%, CI 0.32–0.89) while the preauricular region HNCM revealed the highest rate of discordance with the clinically predictable drainage. The HNCM lymphatic drainage is extremely variable in regard to both the sites and the number of involved SLNs. The lymphoscintigraphic study is highly recommended to identify all possible SLNs in order to perform an accurate staging for all patients and to avoid missing unexpected SLNs.
Early Mortality of Brain Infarction Patients and Red Blood Cell Distribution Width
Authors: Lorente Leonardo , Martín María M. , Abreu-González Pedro , Pérez-Cejas Antonia , González-Rivero Agustín F. , Ramos-Gómez Luis , Argueso Mónica , Solé-Violán Jordi , Cáceres Juan J. , Jiménez Alejandro , García-Marín Victor
Published: March 2020

Background: Meta-analysis has found that high baseline red blood cell distribution width (RDW) is associated with increased long-term mortality (mortality at one year or more) in ischemic stroke. The objectives of this study were to determine whether there is an association between RDW and 30-day mortality, and to explore whether RDW during the first week of ischemic stroke could be a 30-day mortality biomarker. Methods: We included patients with malignant middle cerebral artery infarction (MMCAI). RDW at days 1, 4, and 8 of MMCAI were determined. The end-point study was 30-day mortality. Results: We found that survivor (n = 37) in respect to non-survivor patients (n = 37) had lower RDW at days 1 (p < 0.001), 4 (p < 0.001), and 8 (p = 0.02). The area under curve (95% CI) for prediction of 30-day mortality by RDW at days 1, 4, and 8 of MMCAI were 0.80 (0.69–0.89; p < 0.001), 0.79 (0.66–0.89; p < 0.001), and 0.73 (0.58–0.84; p = 0.02). Regression analysis showed an association between RDW (odds ratio = 1.695; 95% CI = 1.230–2.335; p < 0.001) and 30-day mortality. Conclusions: The association between RDW and early mortality, and the potential role of RDW during the first week of MMCAI as a prognostic biomarker of early mortality were the main novelties of our study.
Aldoxime Dehydratase Mutants as Improved Biocatalysts for a Sustainable Synthesis of Biorenewables-Based 2-Furonitrile
Authors: Choi Ji Eun , Shinoda Suguru , Asano Yasuhisa , Gröger Harald
Published: March 2020

2-Furonitrile is an interesting nitrile product for the chemical industry due to its use as intermediate in the field of fine chemicals and pharmaceuticals or as a potential sweetener, as well as due to its access from biorenewables. As an alternative to current processes based on, e.g., the ammoxidation of furfural with ammonia as a gas phase reaction running at > 400 °C, we recently reported an enzymatic dehydration of 2-furfuryl aldoxime being obtained easily from furfural and hydroxylamine. However, improving the catalytic properties of the aldoxime dehydratase biocatalyst from Rhodococcus sp. YH3-3 (OxdYH3-3) in terms of activity and stability remained a challenge. In this contribution, the successful development of aldoxime dehydratase OxdYH3-3 mutants that were generated by directed evolution and its enhanced activity toward 2-furfuryl aldoxime is reported. The mutant OxdYH3-3 N266S showed an improved activity of up to six times higher than the wild type when utilizing a substrate concentration of 50–100 mM of 2-furfuryl aldoxime.
Electrical Resistivity of Ni–Fe Wires Coated with Sn Using low-Pressure Chemical Vapor Deposition
Authors: Kim Jun-Hyun , Bak Jeong Geun , Kim Chang-Koo
Published: March 2020

In this study, we demonstrated that the deposition of Sn on Ni–Fe wires using low-pressure chemical vapor deposition (LPCVD) can be used to control the electrical resistivity of the wires. Furthermore, the effect of the deposition temperature on the resistivity of the Ni–Fe wires was investigated. The resistivity of the Sn-deposited Ni–Fe wires was found to increase monotonically with the deposition temperature from 550 to 850 °C. Structural and morphological analyses revealed that electron scattering by Ni3Sn2 and Fe3Sn particulates, which were the reaction products of LPCVD of Sn on the surface of the Ni–Fe wires, was the cause of the resistivity increase. These coalesced particulates displayed irregular shapes with an increase in the deposition temperature, and their size increased with the deposition temperature. Owing to these particulate characteristics, the Sn content increased with the deposition temperature. Furthermore, the temperature dependency of the Sn content followed a pattern very similar to that of the resistivity, indicating that the atomic content of Sn directly affected the resistivity of the Ni–Fe wires.
Electrochemical Characterization of CVD-Grown Graphene for Designing Electrode/Biomolecule Interfaces
Authors: Miki Keishu , Watanabe Takeshi , Koh Shinji
Published: March 2020

In research on enzyme-based biofuel cells, covalent or noncovalent molecular modifications of carbon-based electrode materials are generally used as a method for immobilizing enzymes and/or mediators. However, the influence of these molecular modifications on the electrochemical properties of electrode materials has not been clarified. In this study, we present the electrochemical properties of chemical vapor deposition (CVD)-grown monolayer graphene electrodes before and after molecular modification. The electrochemical properties of graphene electrodes were evaluated by cyclic voltammetry and electrochemical impedance measurements. A covalently modified graphene electrode showed an approximately 25-fold higher charge transfer resistance than before modification. In comparison, the electrochemical properties of a noncovalently modified graphene electrode were not degraded by the modification.