bluuebunny/crossref_metadata_2025 huggingface dataset:
Fiber Orientation and Concentration in an Injection-Molded Ethylene-Propylene Copolymer Reinforced by Hemp
Authors: Dupuis Antoine , Pesce Jean-Jacques , Ferreira Paulo , Régnier Gilles
Published: November 2020

This paper characterizes and analyzes the microstructures of injection-molded polypropylene parts reinforced with 20 wt% of hemp fibers in order to understand the process induced variations in thermomechanical properties. In-thickness fiber orientation and fiber content were determined by X-ray tomography along the flow. The fiber content along the flow path was also determined by direct fiber content measurements after matrix dissolution, showing an increase of 2%/100 mm for a 2.2 mm-thick plate due to fiber migration during the filling stage. A typical shell/core structure for fiber orientation in injection molding was observed, but with a very clear transition between the layer solidified under high shear rates and the core in which the fiber content was reduced by more than 50%. The orientation of hemp fibers is lower than the one of glass fibers, especially in thickness direction. However, the overall fiber orientation in the injection direction induces significant anisotropic thermomechanical properties, which cannot be explained by simple micromechanical models that consider isotropic mechanical properties for hemp fibers. These phenomena must be taken into account in process simulation codes for injection molding to better predict thermomechanical properties as well as part shrinkage and warpage to design molds.
Novel Technique for Coating of Fine Particles Using Fluidized Bed and Aerosol Atomizer
Authors: Zhang Rongyi , Hoffmann Torsten , Tsotsas Evangelos
Published: November 2020

Fine particles are widely used in many industrial fields, and there are many techniques applied for these particles, like electroplating, and chemical and physical vapor deposition. However, in the food and pharmaceutical industries, most coating processes conducted with fluidized bed use core particles with a diameter larger than 200 μm, otherwise agglomerates are formed. This study contributes to the development of a new coating process for fine particles with diameters of around 50 μm. The innovation lies in the combined use of a Wurster fluidized bed and a novel aerosol atomizer. The feasibility of the operation is based on the application of the aerosol atomizer, which generates droplets smaller than 1 μm in diameter. A series of experiments with different coating solutions and glass beads in a 150 mm fluidized bed fed with droplet aerosol supplied from the cone chamber bottom is presented. The quality of the coating product is analyzed by scanning electron microscopy and CAMSIZER®. In this way, the influence of different conditions and core material properties on the product quality were determined. Experimental results showed the coating layer quality getting worse as coating solution viscosity became lower, meanwhile moderate process temperature was found to enhance coating layer formation and quality of that. It was also observed that lower aerosol feed rates help improve the yield of the process.
Itaconate Based Elastomer as a Green Alternative to Styrene–Butadiene Rubber for Engineering Applications: Performance Comparison
Authors: Li Liwei , Ji Haijun , Yang Hui , Zhang Liqun , Zhou Xinxin , Wang Runguo
Published: November 2020

In response to increasingly stringent requirements for the sustainability and environmental friendliness of the rubber industry, the application and development of bio-based elastomers have received extensive attention. In this work, we prepared a new type of bio-based elastomer poly(dibutyl itaconate-butadiene) copolymer (PDBIB) nanocomposite using carbon black and non-petroleum-based silica with a coupling agent. Using dynamic thermodynamic analysis (DMTA) and scanning electron microscope (SEM), we studied the effects of feed ratio on dynamic mechanical properties, micro morphology, and filler dispersion of PDBIB composites. Among them, silica-reinforced PDBIB60 (weight ratio of dibutyl itaconate to butadiene 40/60) and carbon black-reinforced PDBIB70 (weight ratio of dibutyl itaconate to butadiene 30/70) both showed excellent performance, such as tensile strength higher than 18 MPa and an elongation break higher than 400%. Compared with the widely used ESBR, the results showed that PDBIB had better rolling resistance and heat generation than ESBR. In addition, considering the development of green tires, we compared it with the solution polymerized styrene–butadiene rubber with better comprehensive performance, and analyzed the advantages of PDBIB and the areas to be improved. In summary, PDBIB prepared from bio-based monomers had superior performance and is of great significance for achieving sustainable development, providing a direction for the development of high-performance green tire and holding great potential to replace petroleum-derived elastomers.
Automating Analysis of Neutron Scattering Time-of-Flight Single Crystal Phonon Data
Authors: Reznik Dmitry , Ahmadova Irada
Published: November 2020

This article introduces software called Phonon Explorer that implements a data mining workflow for large datasets of the neutron scattering function, S(Q, ω), measured on time-of-flight neutron spectrometers. This systematic approach takes advantage of all useful data contained in the dataset. It includes finding Brillouin zones where specific phonons have the highest scattering intensity, background subtraction, combining statistics in multiple Brillouin zones, and separating closely spaced phonon peaks. Using the software reduces the time needed to determine phonon dispersions, linewidths, and eigenvectors by more than an order of magnitude.
Visualizing Near Infrared Hyperspectral Images with Generative Adversarial Networks
Authors: Tang Rongxin , Liu Hualin , Wei Jingbo
Published: November 2020

The visualization of near infrared hyperspectral images is valuable for quick view and information survey, whereas methods using band selection or dimension reduction fail to produce good colors as reasonable as corresponding multispectral images. In this paper, an end-to-end neural network of hyperspectral visualization is proposed, based on the convolutional neural networks, to transform a hyperspectral image of hundreds of near infrared bands to a three-band image. Supervised learning is used to train the network where multispectral images are targeted to reconstruct naturally looking images. Each pair of the training images shares the same geographic location and similar moments. The generative adversarial framework is used with an adversarial network to improve the training of the generating network. In the experimental procedure, the proposed method is tested for the near infrared bands of EO-1 Hyperion images with LandSat-8 images as the benchmark, which is compared with five state-of-the-art visualization algorithms. The experimental results show that the proposed method performs better in producing naturally looking details and colors for near infrared hyperspectral images.
Modeling Australian TEC Maps Using Long-Term Observations of Australian Regional GPS Network by Artificial Neural Network-Aided Spherical Cap Harmonic Analysis Approach
Authors: Li Wang , Zhao Dongsheng , Shen Yi , Zhang Kefei
Published: November 2020

The global ionosphere map (GIM) is not capable of serving precise positioning and navigation for single frequency receivers in Australia due to sparse International GNSS Service (IGS) stations located in the vast land. This study proposes an approach to represent Australian total electron content (TEC) using the spherical cap harmonic analysis (SCHA) and artificial neural network (ANN). The new Australian TEC maps are released with an interval of 15 min for longitude and latitude in 0.5° × 0.5°. The validation results show that the Australian Ionospheric Maps (AIMs) well represent the hourly and seasonally ionospheric electrodynamic features over the Australian continent; the accuracy of the AIMs improves remarkably compared to the GIM and the model built only by the SCHA. The residual of the AIM is inversely proportional to the level of solar radiation. During the equinoxes and solstices in a solar minimum year, the residuals are 2.16, 1.57, 1.68, and 1.98 total electron content units (TECUs, 1 TECU = 1016 electron/m2), respectively. Furthermore, the AIM has a strong capability in capturing the adequate electrodynamic evolutions of the traveling ionospheric disturbances under severe geomagnetic storms. The results demonstrate that the ANN-aided SCHA method is an effective approach for mapping and investigating the TEC maps over Australia.
Perspectives on the Structural Health Monitoring of Bridges by Synthetic Aperture Radar
Authors: Biondi Filippo , Addabbo Pia , Ullo Silvia Liberata , Clemente Carmine , Orlando Danilo
Published: November 2020

Large infrastructures need continuous maintenance because of materials degradation due to atmospheric agents and their persistent use. This problem makes it imperative to carry out persistent monitoring of infrastructure health conditions in order to guarantee maximum safety at all times. The main issue of early warning infrastructure fault detection is that expensive in-situ distributed monitoring sensor networks have to be installed. On the contrary, the use of satellite data has made it possible to use immediate and low-cost techniques in recent years. In this regard, the potential of spaceborne Synthetic Aperture Radar for the monitoring of critical infrastructures is demonstrated in geographically extended areas, even in the presence of clouds, and in really tough weather. A complete procedure for damage early-warning detection is designed, by using micro-motion (m-m) estimation of critical sites, based on modal proprieties analysis. Particularly, m-m is processed to extract modal features such as natural frequencies and mode shapes generated by vibrations of large infrastructures. Several study cases are here considered and the “Morandi” Bridge (Polcevera Viaduct) in Genoa (Italy) is analyzed in depth highlighting abnormal vibration modes during the period before the bridge collapsed.
Statistics of a Sharp GP2Y Low-Cost Aerosol PM Sensor Output Signals
Authors: Bučar Klemen , Malet Jeanne , Stabile Luca , Pražnikar Jure , Seeger Stefan , Žitnik Matjaž
Published: November 2020

In this work, we characterise the performance of a Sharp optical aerosol sensor model GP2Y1010AU0F. The sensor was exposed to different environments: to a clean room, to a controlled atmosphere with known aerosol size distribution and to the ambient atmosphere on a busy city street. During the exposure, the output waveforms of the sensor pulses were digitised, saved and a following offline analysis enabled us to study the behaviour of the sensor pulse-by-pulse. A linear response of the sensor on number concentration of the monosized dispersed PSL particles was shown together with an almost linear dependence on particle diameters in the 0.4 to 4 micrometer range. The gathered data about the sensor were used to predict its response to an ambient atmosphere, which was observed simultaneously with a calibrated optical particle counter.
Review of MAC Protocols for Vehicular Ad Hoc Networks
Authors: Ma Mengyuan , Liu Kai , Luo Xiling , Zhang Tao , Liu Feng
Published: November 2020

Vehicular ad hoc networks (VANETs) need to support the timely end-to-end transmissions of safety and non-safety messages. Medium access control (MAC) protocols can ensure fair and efficient sharing of channel resources among multiple vehicles for VANETs, which can provide timely packet transmissions and significantly improve road safety. In this paper, we review the standards of some countries for VANETs. Then, we divide the MAC protocols proposed for VANETs into single-channel MAC protocols and multi-channel MAC protocols according to the number of physical occupied spectrum resources. Both are further discussed based on their hierarchical structures, i.e., distributed and centralized structures. General design and optimization mechanisms of these commonly used MAC protocols for VANETs are reviewed. From the viewpoint of 7 aspects, we compare the advantages and disadvantages of these typical MAC protocols. Finally, we discuss the open issues to improve the MAC performance and future work on MAC design for VANETs.
Pre-Trained Deep Convolutional Neural Network for Clostridioides Difficile Bacteria Cytotoxicity Classification Based on Fluorescence Images
Authors: Brodzicki Andrzej , Jaworek-Korjakowska Joanna , Kleczek Pawel , Garland Megan , Bogyo Matthew
Published: November 2020

Clostridioides difficile infection (CDI) is an enteric bacterial disease that is increasing in incidence worldwide. Symptoms of CDI range from mild diarrhea to severe life-threatening inflammation of the colon. While antibiotics are standard-of-care treatments for CDI, they are also the biggest risk factor for development of CDI and recurrence. Therefore, novel therapies that successfully treat CDI and protect against recurrence are an unmet clinical need. Screening for novel drug leads is often tested by manual image analysis. The process is slow, tedious and is subject to human error and bias. So far, little work has focused on computer-aided screening for drug leads based on fluorescence images. Here, we propose a novel method to identify characteristic morphological changes in human fibroblast cells exposed to C. difficile toxins based on computer vision algorithms supported by deep learning methods. Classical image processing algorithms for the pre-processing stage are used together with an adjusted pre-trained deep convolutional neural network responsible for cell classification. In this study, we take advantage of transfer learning methodology by examining pre-trained VGG-19, ResNet50, Xception, and DenseNet121 convolutional neural network (CNN) models with adjusted, densely connected classifiers. We compare the obtained results with those of other machine learning algorithms and also visualize and interpret them. The proposed models have been evaluated on a dataset containing 369 images with 6112 cases. DenseNet121 achieved the highest results with a 93.5% accuracy, 92% sensitivity, and 95% specificity, respectively.
Review of Measuring Microenvironmental Changes at the Body–Seat Interface and the Relationship between Object Measurement and Subjective Evaluation
Authors: Liu Zhuofu , Cascioli Vincenzo , McCarthy Peter W.
Published: November 2020

Being seated has increasingly pervaded both working and leisure lifestyles, with development of more comfortable seating surfaces dependent on feedback from subjective questionnaires and design aesthetics. As a consequence, research has become focused on how to objectively resolve factors that might underpin comfort and discomfort. This review summarizes objective methods of measuring the microenvironmental changes at the body–seat interface and examines the relationship between objective measurement and subjective sensation. From the perspective of physical parameters, pressure detection accounted for nearly two thirds (37/54) of the publications, followed by microclimatic information (temperature and relative humidity: 18/54): it is to be noted that one article included both microclimate and pressure measurements and was placed into both categories. In fact, accumulated temperature and relative humidity at the body–seat interface have similarly negative effects on prolonged sitting to that of unrelieved pressure. Another interesting finding was the correlation between objective measurement and subjective evaluation; however, the validity of this may be called into question because of the differences in experiment design between studies.
Multi-Sensor Extrinsic Calibration Using an Extended Set of Pairwise Geometric Transformations
Authors: Santos Vitor , Rato Daniela , Dias Paulo , Oliveira Miguel
Published: November 2020

Systems composed of multiple sensors for exteroceptive perception are becoming increasingly common, such as mobile robots or highly monitored spaces. However, to combine and fuse those sensors to create a larger and more robust representation of the perceived scene, the sensors need to be properly registered among them, that is, all relative geometric transformations must be known. This calibration procedure is challenging as, traditionally, human intervention is required in variate extents. This paper proposes a nearly automatic method where the best set of geometric transformations among any number of sensors is obtained by processing and combining the individual pairwise transformations obtained from an experimental method. Besides eliminating some experimental outliers with a standard criterion, the method exploits the possibility of obtaining better geometric transformations between all pairs of sensors by combining them within some restrictions to obtain a more precise transformation, and thus a better calibration. Although other data sources are possible, in this approach, 3D point clouds are obtained by each sensor, which correspond to the successive centers of a moving ball its field of view. The method can be applied to any sensors able to detect the ball and the 3D position of its center, namely, LIDARs, mono cameras (visual or infrared), stereo cameras, and TOF cameras. Results demonstrate that calibration is improved when compared to methods in previous works that do not address the outliers problem and, depending on the context, as explained in the results section, the multi-pairwise technique can be used in two different methodologies to reduce uncertainty in the calibration process.
Interpretable Cross-Subject EEG-Based Emotion Recognition Using Channel-Wise Features
Authors: Jin Longbin , Kim Eun Yi
Published: November 2020

Electroencephalogram (EEG)-based emotion recognition is receiving significant attention in research on brain-computer interfaces (BCI) and health care. To recognize cross-subject emotion from EEG data accurately, a technique capable of finding an effective representation robust to the subject-specific variability associated with EEG data collection processes is necessary. In this paper, a new method to predict cross-subject emotion using time-series analysis and spatial correlation is proposed. To represent the spatial connectivity between brain regions, a channel-wise feature is proposed, which can effectively handle the correlation between all channels. The channel-wise feature is defined by a symmetric matrix, the elements of which are calculated by the Pearson correlation coefficient between two-pair channels capable of complementarily handling subject-specific variability. The channel-wise features are then fed to two-layer stacked long short-term memory (LSTM), which can extract temporal features and learn an emotional model. Extensive experiments on two publicly available datasets, the Dataset for Emotion Analysis using Physiological Signals (DEAP) and the SJTU (Shanghai Jiao Tong University) Emotion EEG Dataset (SEED), demonstrate the effectiveness of the combined use of channel-wise features and LSTM. Experimental results achieve state-of-the-art classification rates of 98.93% and 99.10% during the two-class classification of valence and arousal in DEAP, respectively, with an accuracy of 99.63% during three-class classification in SEED.
LoRaWAN for Smart Campus: Deployment and Long-Term Operation Analysis
Authors: Yasmin Rumana , Mikhaylov Konstantin , Pouttu Ari
Published: November 2020

The recent years have gradually increased the value of wireless connectivity, making it the de facto commodity for both human users and the machines. In this paper, we summarize our experiences of deploying and managing for over two years the extensive indoor sensor network composed of more than three hundred devices connected over LoRaWAN low power wide area network (LPWAN) technology. We start by detailing the background and methodology of our deployment and then present the results of analyzing the network’s operation over a period of two years, focusing specifically on identifying the reasons after the packet losses. Our results reveal that despite the common assumptions, in a real-life network, the packets are lost not only during the on-air transmission but also within the backbone. Among the other interesting findings are the observed nonuniform distribution of the packet transmissions by the nodes in the networks, the seasonal effects on the packet delivery, and the observed effects of the interferences on network performance. The empirical results presented in the paper provide valuable insight into the performance of a real-life extensive LoRaWAN network deployed in an indoor environment and thus may be of interest both to the practitioners and academics.
The Effects of the Barbell Hip Thrust on Post-Activation Performance Enhancement of Change of Direction Speed in College-Aged Men and Women
Authors: Orjalo Ashley J. , Callaghan Samuel J. , Lockie Robert G.
Published: November 2020

This study investigated whether the barbell hip thrust (BHT) enhanced change-of-direction (COD) speed measured by the 505 COD speed test. Forty recreationally trained individuals completed three sessions. Session 1 included one-repetition maximum (1RM) BHT testing to measure absolute and relative strength. Sessions 2 and 3 involved two counter-balanced conditioning activities (CAs): 3 sets × 5 repetitions of the BHT at 85% 1RM and a control condition (CC; 6 min rest). The 505 COD speed test was performed 5 and 2.5 min pre-CA, and 4, 8, 12, and 16 min post-CA in each session. A 2 × 5 repeated-measures ANOVA (p < 0.05) calculated performance changes across time post-CA. A 2 × 2 repeated-measures ANOVA analyzed best potentiated performance. Partial correlations controlling for sex calculated relationships between the 1RM BHT and 505 COD speed test percent potentiation. There was a significant main effect for time (p < 0.001), but not for condition (p = 0.271) or condition × time (p = 0.295). There were no significant correlations between 1RM BHT and potentiation. The 85% 1RM BHT did potentiate the 505 4–16 min post-CA but no more than the CC. Nonetheless, a heavy BHT could be programmed prior to COD drills as COD speed could be potentiated and performance improved in men and women.
Predicting the Insolvency of SMEs Using Technological Feasibility Assessment Information and Data Mining Techniques
Authors: Lee Sanghoon , Choi Keunho , Yoo Donghee
Published: November 2020

The government makes great efforts to maintain the soundness of policy funds raised by the national budget and lent to corporate. In general, previous research on the prediction of company insolvency has dealt with large and listed companies using financial information with conventional statistical techniques. However, small- and medium-sized enterprises (SMEs) do not have to undergo mandatory external audits, and the quality of accounting information is low due to weak internal control. To overcome this problem, we developed an insolvency prediction model for SMEs using data mining techniques and technological feasibility assessment information as non-financial information. We divided the dataset into two types of data based on three years of corporate age. The synthetic minority over-sampling technique (SMOTE) was used to solve the data imbalance that occurred at this time. Six insolvency prediction models were created using logistic regression, a decision tree, an artificial neural network, and an ensemble (i.e., boosting) of each algorithm. By applying a boosted decision tree, the best accuracies of 69.1% and 82.7% were derived, and by applying a decision tree, nine and seven influential factors affected the insolvency of SMEs established for fewer than three years and more than three years, respectively. In addition, we derived several insolvency rules for the two types of SMEs from the decision tree-based prediction model and proposed ways to enhance the health of loans given to potentially insolvent companies using these derived rules. The results of this study show that it is possible to predict SMEs’ insolvency using data mining techniques with technological feasibility assessment information and find meaningful rules related to insolvency.
Socioeconomics Determinants to Adopt Agricultural Machinery for Sustainable Organic Farming in Pakistan: A Multinomial Probit Model
Authors: Akram Muhammad Waqar , Akram Nida , Wang Hongshu , Andleeb Shahla , Ur Rehman Khalil , Kashif Umair , Hassan Syed Farhaan
Published: November 2020

Urbanization and low productivity are real threats to the sustainability of organic farming. The adoption of farm machinery plays a vital role in overcoming these threats to ensure a sustainable and more profitable organic farming model. Farm machinery can also increase farmland yield and reduce the need for labor, although the requirement of significant capital investment often prevents small farmers from buying machinery. There is an increased need to comprehend all relevant elements associated with farming machinery procurement and service delivery. In this article, we provide insight into the impact of different variables of farmers on the adoption of agricultural equipment. A total of 301 organic farmers were surveyed in three districts of Punjab, Pakistan. It was found that the most common machinery concerned herein are tube-well/pumps, tractors, tillage machinery, and thrashers/harvesters. Results from a multinomial probit estimation showed that farm machinery ownership is positively correlated with capital assets, civil infrastructure, alternative sources of power, and credit facility. The findings indicated that policymakers and stakeholders should not concentrate merely on short term planning, such as improving agricultural machinery’s adoption rate. Still, they should also strive to upgrade physical infrastructure and facilities and provide credit services to create an enabling environment that can empower the citizen in adopting large scale use of agricultural machinery for long term sustainability of organic farming.
Human Posture Estimation and Sustainable Events Classification via Pseudo-2D Stick Model and K-ary Tree Hashing
Authors: Jalal Ahmad , Akhtar Israr , Kim Kibum
Published: November 2020

This paper suggests that human pose estimation (HPE) and sustainable event classification (SEC) require an advanced human skeleton and context-aware features extraction approach along with machine learning classification methods to recognize daily events precisely. Over the last few decades, researchers have found new mechanisms to make HPE and SEC applicable in daily human life-log events such as sports, surveillance systems, human monitoring systems, and in the education sector. In this research article, we propose a novel HPE and SEC system for which we designed a pseudo-2D stick model. To extract full-body human silhouette features, we proposed various features such as energy, sine, distinct body parts movements, and a 3D Cartesian view of smoothing gradients features. Features extracted to represent human key posture points include rich 2D appearance, angular point, and multi-point autocorrelation. After the extraction of key points, we applied a hierarchical classification and optimization model via ray optimization and a K-ary tree hashing algorithm over a UCF50 dataset, an hmdb51 dataset, and an Olympic sports dataset. Human body key points detection accuracy for the UCF50 dataset was 80.9%, for the hmdb51 dataset it was 82.1%, and for the Olympic sports dataset it was 81.7%. Event classification for the UCF50 dataset was 90.48%, for the hmdb51 dataset it was 89.21%, and for the Olympic sports dataset it was 90.83%. These results indicate better performance for our approach compared to other state-of-the-art methods.
Assessing Master Students’ Competencies Using Rubrics: Lessons Learned from Future Secondary Education Teachers
Authors: Isusi-Fagoaga Rosa , García-Aracil Adela
Published: November 2020

The aim of this paper is to provide insights into the appropriateness of teaching-learning and evaluation processes using rubrics, for student self-assessments. We studied students enrolled on the Master’s in Secondary Education Teaching—Music Specialism course. In the Spanish secondary education system, music is seen as increasing equity and improving student performance in line with the Agenda 2030 Sustainable Development Goals. The training of new teachers and the ongoing professional development of the current teaching force are critical for improving the quality of education. We adopted an action-research approach and obtained feedback from the Masters’ students via questionnaires administered at the start and end of the process (pre- and post-test). Our results show that using rubrics as formative and shared assessment tools has a positive influence on students’ perceptions of their acquisition of both transversal and specific competencies, as well as demonstrating the utility of rubrics for their future professional practice. However, rubrics on their own are not sufficient to increase the facility for learning and awareness among students.
Atomistic Investigation of Material Deformation Behavior of Polystyrene in Nanoimprint Lithography
Authors: Odujole Jahlani , Desai Salil
Published: November 2020

This research investigates deformation behavior of polystyrene (PS) as a thermoplastic resist material for the thermal nanoimprint lithography (T-NIL) process. Molecular dynamics modeling was conducted on a PS substrate with dimensions 58 × 65 × 61 Å that was imprinted with a rigid, spherical indenter. The effect of indenter size, force, and imprinting duration were evaluated in terms of indentation depth, penetration depth, recovery depth, and recovery percentage of the polymer. The results show that the largest indenter, regardless of force, has the most significant impact on deformation behavior. The 40 Å indenter with a 1 µN of force caused the surface molecules to descend to the lowest point compared to the other indenters. An increase in indenter size resulted in higher penetration depth, recovery depth, and recovery percentage. Higher durations of imprint cycle (400 fs) resulted in plastic deformation of the PS material with minimal recovery (4 Å). The results of this research lay the foundation for explaining the effect of several T-NIL process parameters on virgin PS thermoplastic resist material.
Investigating the Efficiency of Hydroxycinnamic Acids to Inhibit the Production of Enniatins by Fusarium avenaceum and Modulate the Expression of Enniatins Biosynthetic Genes
Authors: Gautier Charlotte , Pinson-Gadais Laetitia , Verdal-Bonnin Marie-Noelle , Ducos Christine , Tremblay Judith , Chéreau Sylvain , Atanasova Vessela , Richard-Forget Florence
Published: November 2020

Enniatins (ENNs) that belong to the group of emerging mycotoxins are widespread contaminants of agricultural commodities. There is currently insufficient evidence to rule out health concerns associated with long-term exposure to ENNs and efforts must be strengthened to define a control strategy. While the potential of plant compounds to counteract the contamination with legislated mycotoxins has been reported, little remains known regarding ENNs. The present study evidenced for the first time the efficiency of hydroxycinnamic acids to inhibit the fungal growth and ENNs yield by Fusarium avenaceum. Notably, 0.5 mM of exogenous ferulic, caffeic, and p-coumaric acids led to a drastic reduction of ENNs synthesis in pH4 broths, with ferulic acid being the most potent. The ENNs production inhibitory activity of ferulic acid was shown to be associated with a significant down-regulation of the expression of ENNs biosynthetic genes. To further investigate the bioactivity of ferulic acid, its metabolic fate was characterized in fungal broths and the capacity of F. avenaceum to metabolize it through a C2-cleavage type degradation was demonstrated. Overall, our data support the promising use of ferulic acid in ENNs control strategies, either as part of an environmentally friendly plant-care product or as a biomarker of plant resistance.
Determination of Ochratoxin A and Ochratoxin B in Archived Tokaj Wines (Vintage 1959–2017) Using On-Line Solid Phase Extraction Coupled to Liquid Chromatography
Authors: Kholová Aneta , Lhotská Ivona , Uhrová Adéla , Špánik Ivan , Machyňáková Andrea , Solich Petr , Švec František , Šatínský Dalibor
Published: November 2020

According to the EU legislation, ochratoxin A contamination is controlled in wines. Tokaj wine is a special type of sweet wine produced from botrytized grapes infected by “noble rot” Botrytis cinerea. Although a high contamination was reported in sweet wines and noble rot grapes could be susceptible to coinfection with other fungi, including ochratoxigenic species, no screening of Tokaj wines for mycotoxin contamination has been carried out so far. Therefore, we developed an analytical method for the determination of ochratoxin A (OTA) and ochratoxin B (OTB) involving online SPE coupled to HPLC-FD using column switching to achieve the fast and sensitive control of mycotoxin contamination. The method was validated with recoveries ranging from 91.6% to 99.1% with an RSD less than 2%. The limits of quantification were 0.1 and 0.2 µg L−1 for OTA and OTB, respectively. The total analysis time of the online SPE-HPLC-FD method was a mere 6 min. This high throughput enables routine analysis. Finally, we carried out an extensive investigation of the ochratoxin contamination in 59 Slovak Tokaj wines of 1959–2017 vintage. Only a few positives were detected. The OTA content in most of the checked wines did not exceed the EU maximum tolerable limit of 2 µg L−1, indicating a good quality of winegrowing and storing.
Low Aedes aegypti Vector Competence for Zika Virus from Viremic Rhesus Macaques
Authors: Fernandes Rosilainy Surubi , David Mariana Rocha , De Abreu Filipe Vieira Santos , Ferreira-de-Brito Anielly , Gardinali Noemi R. , Lima Sheila Maria Barbosa , Andrade Márcia Cristina Ribeiro , Kugelmeier Tatiana , Oliveira Jaqueline Mendes de , Pinto Marcelo A. , Lourenço-de-Oliveira Ricardo
Published: November 2020

Despite worldwide efforts to understand the transmission dynamics of Zika virus (ZIKV), scanty evaluation has been made on the vector competence of Aedes aegypti fed directly on viremic human and non-human primates (NHPs). We blood-fed Ae. aegypti from two districts in Rio de Janeiro on six ZIKV infected pregnant rhesus macaques at several time points, half of which were treated with Sofosbuvir (SOF). Mosquitoes were analyzed for vector competence after 3, 7 and 14 days of incubation. Although viremia extended up to eight days post monkey inoculation, only mosquitoes fed on the day of the peak of viremia, recorded on day two, became infected. The influence of SOF treatment could not be assessed because the drug was administered just after mosquito feeding on day two. The global infection, dissemination and transmission rates were quite low (4.09%, 1.91% and 0.54%, respectively); no mosquito was infected when viremia was below 1.26 × 105 RNA copies/mL. In conclusion, Ae. aegypti vector competence for ZIKV from macaques is low, likely to be due to low viral load and the short duration of ZIKV viremia in primates suitable for infecting susceptible mosquitoes. If ZIKV infection in human and macaques behaves similarly, transmission of the Zika virus in nature is most strongly affected by vector density.
Hydroclimatic Extremes in the Limpopo River Basin, South Africa, under Changing Climate
Authors: Botai Christina M. , Botai Joel O. , Zwane Nosipho N. , Hayombe Patrick , Wamiti Eric K. , Makgoale Thabo , Murambadoro Miriam D. , Adeola Abiodun M. , Ncongwane Katlego P. , de Wit Jaco P. , Mengistu Michael G. , Tazvinga Henerica
Published: November 2020

This research study evaluated the projected future climate and anticipated impacts on water-linked sectors on the transboundary Limpopo River Basin (LRB) with a focus on South Africa. Streamflow was simulated from two CORDEX-Africa regional climate models (RCMs) forced by the 5th phase of the Coupled Model Inter-Comparison Project (CMIP5) Global Climate Models (GCMs), namely, the CanESM2m and IPSL-CM5A-MR climate models. Three climate projection time intervals were considered spanning from 2006 to 2099 and delineated as follows: current climatology (2006–2035), near future (2036–2065) and end of century future projection (2070–2099). Statistical metrics derived from the projected streamflow were used to assess the impacts of the changing climate on water-linked sectors. These metrics included streamflow trends, low and high flow quantile probabilities, the Standardized Streamflow Index (SSI) trends and the proportion (%) of dry and wet years, as well as drought monitoring indicators. Based on the Mann-Kendall (MK) trend test, the LRB is projected to experience reduced streamflow in both the near and the distant future. The basin is projected to experience frequent dry and wet conditions that can translate to drought and flash floods, respectively. In particular, a high proportion of dry and a few incidences of wet years are expected in the basin in the future. In general, the findings of this research study will inform and enhance climate change adaptation and mitigation policy decisions and implementation thereof, to sustain the livelihoods of vulnerable communities.
Can Zooplankton Be Entangled by Microfibers in the Marine Environment?: Laboratory Studies
Authors: Kang Jung-Hoon , Kwon Oh-Youn , Hong Sang Hee , Shim Won Joon
Published: November 2020

We investigated the probability of copepod entanglement in microfibers in a laboratory experiment. This experiment was inspired by an accidental observation of entangled copepods with microfibers during isolating copepods for grazing experiments. The exposure of microfibers to copepods was designed by applying conditions similar to environmentally relevant concentrations of microfibers to zooplankton in the Yellow Sea as well as highly elevated concentrations of microfibers compared to the previously reported maximum natural concentration. Copepod entanglement in microfibers was reproduced in laboratory. The entanglement was not observed in the condition which simulated the environmental scenario of copepods outnumbering microfibers observed in the Yellow Sea, while it occurred inconsistently in the conditions of the maximum and 10-fold maximum natural concentrations of microfibers. However, consistent entanglement of copepods by microfibers was found in the 100-fold maximum environmental concentration of microfibers. These results suggest that copepod entanglement by microfibers can happen accidentally under the maximum natural concentration of microfibers occurring in the marine environment; however, copepods are likely to be entangled in microfibers consistently if copepods encounter highly enhanced concentration of microfibers.
General practitioners’ drug treatment for depression by patients’ educational level: registry-based study
Authors: Hansen Anneli Borge , Baste Valborg , Hetlevik Oystein , Haukenes Inger , Smith-Sivertsen Tone , Sabine Ruths
Published: November 2020

Background: Antidepressant drugs are often prescribed in general practice. Evidence is conflicting on how patient education influences antidepressant treatment. Aim: To investigate the association between educational attainment and drug treatment in adult patients with a new depression diagnosis, and how gender and age influence the association. Design and setting: Nationwide registry-based cohort study, Norway, 2014-2016. Method: The study comprised all residents of Norway born before 1996 and alive in 2015. We obtained information on all new depression diagnoses in general practice in 2015 (Primary Care Database) and data on all dispensed depression medication (Norwegian Prescription Database) 12-months after the date of diagnosis. Independent variables were education, gender, and age. Associations with drug treatment were estimated using a Cox proportional hazard model, for genders separately. Results: Out of 49,967 patients with new depression (61.6% women), 15,678 were dispensed drugs (30.4% women, 33.0% men). Highly educated women were less likely to receive medication (Hazard Ratio (HR) =0.93, 95% CI (0.88 – 0.98)) than women with low education. No such differences appeared among men. Women aged 20-29 were more likely to be treated with drugs than those aged 30-59, and women aged 70+ were more likely to receive drugs (HR=1.65, (1.54 – 1.77)) than those aged 20-29. The pattern was similar but less pronounced for men. Conclusion: Educational differences in antidepressant therapy among women may reflect different treatment approaches that clinicians should be aware of to avoid unintended variation. Reasons for this variation and consequences for quality of treatment should be
Identifikasi Situs Geologi Cekungan Soa - Flores, Sebagai Salah Satu Warisan Geologi
Authors: Djafar Agustina , Suharyogi Ifan Yoga Pratama , Wibowo Unggul Prasetyo
Published: November 2020

ABSTRAK Cekungan Soa secara geografis terletak pada koordinat 80 39’ 00” LS - 80 46’ 00” LS dan 1210 03’ 00” BT - 1210 13’ 00” BT dan secara administratif terletak di Kabupaten Ngada dan Kabupaten Nagekeo, Pulau Flores, Nusa Tenggara Timur. Cekungan Soa memiliki keragaman geologi yang unik dan dapat dikembangkan menjadi destinasi geowisata yang menarik. Tujuan studi ini adalah untuk menginvetariasi keragaman geologi di Cekungan Soa, mengklasifikasikan peringkat nilai keragaman geologinya berdasarkan manfaatnya untuk selanjutnya dilakukan penilaian secara kuantitatif sebagai situs warisan geologi (geoheritage), dan merekomendasikan potensi situs warisan geologi tersebut untuk dikonservasi dalam bentuk Kawasan Cagar Alam Geologi (KCAG). Metode yang digunakan dalam studi ini berdasarkan “Standar teknis inventarisasi keragaman geologi dan Petunjuk Teknis Asesmen Sumberdaya Geologi” yang dikeluarkan oleh Pusat Survei Geologi pada tahun 2017. Ada 24 situs keragaman geologi di Cekungan Soa, yang memiliki peringkat nilai keragaman geologi menengah hingga terkemuka berdasarkan rekaman ilmiah dan fenomena geologi khusus untuk tujuan pendidikan maupun penelitian, sehingga pantas dijadikan sebagai geoheritage. Salah satunya adalah Situs Mata Menge yang memiliki nilai scientific sangat tinggi (91,25%). Dari hasil studi, kawasan Cekungan Soa direkomendasikan untuk dikonservasi menjadi KCAG.Kata kunci: Cekungan Soa, geowisata, keragaman geologi, warisan geologi, Kawasan Cagar Alam GeologiABSTRACT Soa Basin geographically situated at 80 39’ 00” S - 80 46’ 00” S and 1210 03’ 00” E - 1210 13’ 00” E in Ngada and Nagekeo District, Flores Island, East Nusa Tenggara. Soa Basin has unique geodiversity and can be developed into an interesting geotourism destination. This study aims to inventory the geological sites in the Soa Basin, to classify them as the geoheritage and to recommend them to be conserved in the form of Geoconservation Area (GCA). The method used in this study is based on the “Technical Standard of Geological Diversity Inventory and Technical Guidelines for Geological Resource Assessment” issued by the Geological Survey Center in 2017. There are 24 sites of geodiversities in the Soa Basin, which rank intermediate to prominent geological diversity values based on its scientific records and geological phenomena specifically for educational and research purposes, so the Soa Basin deserve to become as a geoheritage. Mata Menge, one of the site, has a very high scientific value of 91.25%. From the results of the assessment, it is recommended that the Soa Basin area be conserved as a GCA.Keywords: Soa Basin, geotourism, geodiversity, geoheritage, Geoconservation Are
Avaliação ultrassonográfica de estruturas reprodutivas, fígado e vesícula biliar de Boa constrictor (Linnaeus, 1758) ex situ
Authors: Do Prado Carolina Melchior , Dislich Mathias , Clasta Ricardo Birolini , Cubas Zalmir Silvino
Published: November 2020

A ultrassonografia possibilita avaliações que resultam em informações relevantes para a manutenção das espécies em cativeiro. Desse modo, realizou-se um estudo com 15 exemplares de Boa constrictor, de ambos os sexos, a fim de caracterizar a aparência ultrassonográfica das estruturas reprodutivas, fígado e vesícula biliar desses animais, pela técnica da janela lateral. Além disso, avaliou-se a influência dos fatores intervalo entre alimentações e o tamanho dos indivíduos na caracterização ultrassonográfica das estruturas. Folículos pré-vitelogênicos foram caracterizados por formato arredondado, preenchidos basicamente por conteúdo anecoico e com ecotextura homogênea e grosseira e folículos vitelogênicos apresentaram conteúdo anecogênico e hipoecogênico, ambos com margens finas e regulares. Os testículos foram caracterizados por formato alongado, parênquima com média ecogenicidade, margens regulares e ecotextura homogênea. O fígado apresentou formato alongado, parênquima com ecogenicidade mista (hipoecoico a levemente hiperecoico), margens ecogênicas, ecotextura homogênea e tamanho médio de 27,6 cm. A vesícula biliar apresentou formato arredondado, preenchida por conteúdo anecoico, envolvida por uma margem fina hiperecogênica. Dos fatores avaliados, o intervalo entre alimentações foi o que mais influenciou na caracterização ultrassonográfica das estruturas. O tamanho das serpentes não exerceu nenhuma influência. Foi possível concluir que o ultrassom, por meio da técnica da janela lateral, é eficaz na avaliação dos órgãos estudados.
Kobalt Katkılı Kalsiyum Manganez Oksit Numunelerin Sentez ve Karakterizasyonu
Authors: ATEŞ Tankut , KÖYTEPE Süleyman , KAYGILI Omer
Published: November 2020

Bu çalışmada, kobalt katkılı kalsiyum manganez oksit numunelerinin faz bileşimleri, kristal yapıları, yüzey morfolojileri ve termal özellikleri karakterize edildi. Co miktarının bu oksit yapı üzerindeki etkileri belirlendi. X-ışını kırınımı (XRD) sonuçları, kalsiyum manganez oksit fazlarının oluşumuna işaret etmektedir. Fourier dönüşümlü kızılötesi (FTIR) analizleri, her bir numune için peroksit yapısının oluşumunu doğrulamaktadır. Termal analiz sonuçları, üretilen numunelerin termal olarak kararlı olduklarını göstermektedir. Numunelerin taramalı elektron mikroskobu (SEM) gözlemleri ve enerji dağılımlı X-ışını (EDX) analizleri, Co katkısının morfolojiye etki ettiğini ve kalsiyum manganez oksit yapıya nüfuz ettiğini desteklemektedir.
Cr2O3 Nanoyapılarının Elektrokimyasal Sentezi ve Karakterizasyonu
Authors: KORKMAZ Ahmet Recep , ÇEPNİ Emir , ÖZTÜRK DOĞAN Hülya
Published: November 2020

Bu çalışmada krom(III) oksit (Cr2O3) nanoyapıları flor katkılı kalay oksit (FTO) kaplı cam elektrot yüzeyinde elektrokimyasal teknik kullanılarak sentezlenmiştir. Elektrolit çözeltisi olarak CrCl3 içeren ortamda öncelikle krom oksihidroksit türleri oluşturulmuş ve sonrasında ısıl işlem uygulanarak oksit formuna dönüşüm sağlanmıştır. Elektrokimyasal sentez üzerine indirgenme potansiyeli ve depozisyon süresinin etkisi incelenmiştir. Elektrokimyasal olarak biriktirilen Cr2O3 nanoyapılarının karakterizasyonu XRD, SEM ve EDS teknikleri kullanılarak gerçekleştirilmiştir. -1,4 V sabit potansiyelde hazırlanan Cr2O3 nanoyapılarının XRD spektrumunda Cr2O3’in (110) düzlemine ait kırınım piki elde edilmiştir. EDS spektrumu ise elementel olarak oldukça saf Cr2O3 nanoyapılarının sentezlendiğini desteklemiştir.