bluuebunny/crossref_metadata_2025 huggingface dataset:
Directed Data-Processing Inequalities for Systems with Feedback
Authors: Derpich Milan S. , Østergaard Jan
Published: April 2021

We present novel data-processing inequalities relating the mutual information and the directed information in systems with feedback. The internal deterministic blocks within such systems are restricted only to be causal mappings, but are allowed to be non-linear and time varying, and randomized by their own external random input, can yield any stochastic mapping. These randomized blocks can for example represent source encoders, decoders, or even communication channels. Moreover, the involved signals can be arbitrarily distributed. Our first main result relates mutual and directed information and can be interpreted as a law of conservation of information flow. Our second main result is a pair of data-processing inequalities (one the conditional version of the other) between nested pairs of random sequences entirely within the closed loop. Our third main result introduces and characterizes the notion of in-the-loop (ITL) transmission rate for channel coding scenarios in which the messages are internal to the loop. Interestingly, in this case the conventional notions of transmission rate associated with the entropy of the messages and of channel capacity based on maximizing the mutual information between the messages and the output turn out to be inadequate. Instead, as we show, the ITL transmission rate is the unique notion of rate for which a channel code attains zero error probability if and only if such an ITL rate does not exceed the corresponding directed information rate from messages to decoded messages. We apply our data-processing inequalities to show that the supremum of achievable (in the usual channel coding sense) ITL transmission rates is upper bounded by the supremum of the directed information rate across the communication channel. Moreover, we present an example in which this upper bound is attained. Finally, we further illustrate the applicability of our results by discussing how they make possible the generalization of two fundamental inequalities known in networked control literature.
Using Blended Project-Based Learning for Students’ Behavioral Intention to Use and Academic Achievement in Higher Education
Authors: Alamri Mahdi Mohammed
Published: April 2021

This research focused on the potential of project-based learning and blended learning, which offer a distinctive cross-point in regard to building 21st-century skills in the classroom. Specifically, this research hypothesized that using the BPBL approach has an effect on perceived self-efficacy, perceived enjoyment, perceived usefulness, behavioral intention of using BPBL, and students’ academic achievement. To achieve the research goal, we employed a questionnaire as the main data collection method and dispensed it to 80 students, all of whom use the BPBL approach. The findings were obtained via a quantitative research method, structural equation modeling (SEM). We found a significant relationship between the BPBL approach and perceived self-efficacy, perceived enjoyment, perceived usefulness, behavioral intention of using BPBL, and students’ academic achievement. Therefore, we believe that the BPBL approach enhances students’ behavioral intention to use and academic achievement in a blended project-based learning approach and allows sharing knowledge, information, and discussions. Thus, it is recommended that students use the BPBL approach for educational purposes, and they should also be encouraged to do so through their learning at university level.
The Study of Monotonic Core Functions and Their Use to Build RNS Number Comparators
Authors: Babenko Mikhail , Piestrak Stanislaw J. , Chervyakov Nikolay , Deryabin Maxim
Published: April 2021

A non-positional residue number system (RNS) enjoys particularly efficient implementation of addition and multiplication, but non-modular arithmetic operations in RNS-like number comparison are known to be difficult. In this paper, a new technique for designing comparators of RNS numbers represented in an arbitrary moduli set is presented. It is based on using the core function for which it was shown that it must be monotonic to allow for RNS number comparison. The conditions of the monotonicity of the core function were formulated, which also ensured the minimal range of the core function (essential to obtain the best characteristics of the comparator). The best choice is a core function in which only one coefficient corresponding to the largest modulus is set to 1 whereas all other coefficients are set to 0. It is also shown that the already known diagonal function is nothing else but the special case of the core function with all coefficients set to 1. Performance evaluation suggests that the new comparator uses less hardware and in some cases also introduces smaller delay than its counterparts based on diagonal function. The potential applications of the new comparator include some recently developed homomorphic encryption algorithms implemented using RNS.
Evaluate the Cooling Performance of Transmit/Receive Module Cooling System in Active Electronically Scanned Array Radar
Authors: Park Jun Su , Shin Dong-Jun , Yim Sung-Hwan , Kim Sang-Hyun
Published: April 2021

The active electronically scanned array (AESA) radar consists of many transmit/receive (T/R) modules and is used to track missiles approaching destroyers and fighters. The performance of the AESA radar depends on the T/R module temperature. The T/R module temperature should be maintained under 80 °C to guarantee the performance of the AESA radar. In order to match the design requirements of the cooling system of the AESA radar, it is necessary to evaluate the cooling performance according to various operation/installation environments. In this study, computational fluid analysis was performed by changing the number of T/R modules and the coolant mass flow rate to evaluate the cooling performance of the AESA radar coolant channel. The number of T/R modules was changed from 2 to 16, and the number of coolant inlet Re was changed from 277 to 11,116. As a result, it was confirmed that the temperature increased as the number of T/R modules increased. In addition, when the coolant status was laminar flow, it was confirmed that the cooling performance was significantly lowered. Therefore, the coolant status should be transient or turbulence to decrease the temperature of the T/R module. Additionally, the correlation between the arrangement of the T/R module and the cooling flow must be considered to cool the AESA radar.
An Efficient Stereo Matching Network Using Sequential Feature Fusion
Authors: Jeong Jaecheol , Jeon Suyeon , Heo Yong Seok
Published: April 2021

Recent stereo matching networks adopt 4D cost volumes and 3D convolutions for processing those volumes. Although these methods show good performance in terms of accuracy, they have an inherent disadvantage in that they require great deal of computing resources and memory. These requirements limit their applications for mobile environments, which are subject to inherent computing hardware constraints. Both accuracy and consumption of computing resources are important, and improving both at the same time is a non-trivial task. To deal with this problem, we propose a simple yet efficient network, called Sequential Feature Fusion Network (SFFNet) which sequentially generates and processes the cost volume using only 2D convolutions. The main building block of our network is a Sequential Feature Fusion (SFF) module which generates 3D cost volumes to cover a part of the disparity range by shifting and concatenating the target features, and processes the cost volume using 2D convolutions. A series of the SFF modules in our SFFNet are designed to gradually cover the full disparity range. Our method prevents heavy computations and allows for efficient generation of an accurate final disparity map. Various experiments show that our method has an advantage in terms of accuracy versus efficiency compared to other networks.
An Interval Optimization-Based Approach for Electric–Heat–Gas Coupled Energy System Planning Considering the Correlation between Uncertainties
Authors: Wang Wenshi , Dong Houqi , Luo Yangfan , Zhang Changhao , Zeng Bo , Xu Fuqiang , Zeng Ming
Published: April 2021

In this paper, a novel methodological framework for energy hub (EH) planning, considering the correlation between renewable energy source (RES) and demand response (DR) uncertainties, is proposed. Unlike other existing works, our study explicitly considers the potential correlation between the uncertainty of integrated energy system operations (i.e., wind speed, light intensity, and demand response). Firstly, an EH single-objective interval optimization model is established, which aims at minimizing investment and operation costs. The model fully considers the correlation between various uncertain parameters. Secondly, the correlation between uncertainties is dealt with by the interval models of multidimensional parallelism and affine coordinate transformation, which are transformed into a deterministic optimization problem by the interval order relationship and probability algorithm, and then solved by a genetic algorithm. Finally, an experimental case is analyzed, and the results show that the research method in this paper has good engineering practicability. At the same time, different correlations among uncertainties have different influences on integrated energy system planning. Correlation and influence are positively correlated.
Treatment of Flue Gas in a CO2 Capture Pilot Plant for a Commercial CFB Boiler
Authors: Majchrzak-Kucęba Izabela , Wawrzyńczak Dariusz , Zdeb Janusz , Smółka Wojciech , Zajchowski Artur
Published: April 2021

The problem of reducing carbon dioxide emissions from flue gas, particularly from flue gas originating from coal-firing CFB systems, is currently an important challenge. Many centers around the world have tested post-combustion CO2 capture systems. One of these systems, operated using DR-VPSA adsorption technology (dual-reflux vacuum pressure swing adsorption), was tested under the Strategic Project in Poland. The flue gas in this study originated from a supercritical CFB boiler (460 MWe). An important problem involved in capturing CO2 from flue gas is the occurrence of SO2 and NOx. These substances have a negative effect on the CO2 adsorption process. In this study, commercial impregnated activated carbon was used to remove SO2 and NOx from CFB flue gas in the pre-treatment section during the tests of a pilot CO2 capture unit in a large-scale CFB boiler at the Lagisza Power Plant (Poland). The spent activated carbon was analyzed using several different methods (N2 adsorption–desorption isotherms, SEM-EDX, XRD, FTIR, and TG) to evaluate the efficiency of the operation and life span of the adsorbent used in the SO2 and NOx removal unit. The results demonstrate that using commercial impregnated activated carbon in the pre-treatment section ensures sufficient flue gas purification and the removal of sulfur oxides but remains insufficient for nitrogen oxides.
Effect of Polypyrrole-Fe3O4 Composite Modified Anode and Its Electrodeposition Time on the Performance of Microbial Fuel Cells
Authors: Fan Liping , Xi Yaobin
Published: April 2021

Anode modification is a useful method to increase the performance of microbial fuel cells (MFCs). By using the electrochemical deposition method, Fe3O4 and polypyrrole (PPy) were polymerized on a carbon felt anode to prepare Fe3O4-PPy composite modified anodes. In order to ascertain the effect of electrodeposition time on characteristics of the modified electrode, the preparation time of the modified electrode was adjusted. The modified anodes were used in MFCs, and their performances were evaluated by analyzing the electricity generation performance and sewage treatment capacity of MFCs. Experimental results indicated that the Fe3O4-PPy composite modified anodes could enhance the power production capacity and sewage treatment efficiency of MFC effectively. In particular, when the deposition time was 50 min, the modified anode could significantly improve the MFC performance. In this case, the steady-state current density of MFC increased by 59.5% in comparison with that of the MFC with an unmodified carbon felt anode, and the chemical oxygen demand (COD) removal rate was 95.3% higher than that of the unmodified anode. Therefore, the Fe3O4-PPy composite is an effective material for electrode modification, and a good anode modification effect can be obtained by selecting the appropriate electrodeposition time.
Composed Index for the Evaluation of Energy Security in Power Systems within the Frame of Energy Transitions—The Case of Latin America and the Caribbean
Authors: Fuentes Sergio , Villafafila-Robles Roberto , Rull-Duran Joan , Galceran-Arellano Samuel
Published: April 2021

Energy transitions are transforming energy systems around the globe. Such a shift has caused the power system to become a critical piece of infrastructure for the economic development of every nation on the planet. Therefore, guaranteeing its security is crucial, not only for energy purposes but also as a part of a national security strategy. This paper presents a multidimensional index developed to assess energy security of electrical systems in the long term. This tool, named the Power System Security Index (PSIx), which has been previously used for the evaluation of a country in two different time frames, is applied to evaluate the member countries of the Latin American Energy Organization, located within the Latin America and the Caribbean region, to measure its performance on energy security. Mixed results were obtained from the analysis, with clear top performers in the region such as Argentina, while there are others with broad areas of opportunity, as is the case of Haiti.
Impact on Current-Interrupting Characteristic by Parameter Settings of Superconducting Hybrid DC Circuit Breaker
Authors: Choi Sang-Jae , Lim Sung-Hun
Published: April 2021

DC faults cause severe disruption in not only the DC system but also the AC system because the fault current is very large and rapidly increases. The DC circuit breaker used to separate the DC faults from the power system is still being researched, but it is very expensive due to the use of multiple power semiconductors to interrupt a large fault current in a short time. However, if the quench characteristic of a superconductor is used, the amplitude of fault current can be reduced. Therefore, it is possible to effectively interrupt a large fault current even if a relatively cheap mechanically passive DC circuit breaker is used. In the current study, a superconducting hybrid DC circuit breaker is proposed, and the limiting characteristics of each element are analyzed. By using two superconducting elements, the quench occurs sequentially twice according to the magnitude of the fault current, and the current-limiting reactor and resistance are used. If a current-limiting reactor is used in the DC system, the fault current rises slowly at the beginning of the fault, and the use of resistance can reduce the magnitude of the fault current. The inductance of the current-limiting reactor and resistance parameter settings of the hybrid DC circuit breaker was analyzed by the step-changing case method, and the interrupting characteristic of the DC circuit breaker was improved.
Weed Management Practices to Improve Establishment of Selected Lignocellulosic Crops
Authors: Gazoulis Ioannis , Kanatas Panagiotis , Papastylianou Panayiota , Tataridas Alexandros , Alexopoulou Efthymia , Travlos Ilias
Published: April 2021

Lignocellulosic biomass is one of the dominant renewable energy resources suited for the production of sustainable biofuels and other energy purposes. This study was focused on weed management strategies that can improve the establishment of six lignocellulosic crops. The studied crops included: giant miscanthus, switchgrass, giant reed, cardoon, sweet sorghum, and kenaf. Delayed planting, increased planting densities, and mulching techniques can suppress weeds in giant miscanthus. Weed competition is detrimental for switchgrass establishment. Seedbed preparation and cultivar selection can determine its ability to compete with weeds. Giant reed is unlikely to get outcompeted by weeds, and any weed control operation is required only for the first growing season. Competitive cultivars and increased seeding rates maximize the competitiveness of cardoon against weeds. Several cultural practices can be used for non-chemical weed management in sweet sorghum and kenaf. For all crops, pre-emergence herbicides can be applied. The available safe post-emergence herbicides are limited. Mechanical weed control during crucial growth stages can provide solutions for sweet sorghum, kenaf, and perennial grasses. Further research is required to develop effective weed management strategies, with emphasis on cultural practices, that can improve the establishment of these prominent lignocellulosic crops.
Modelling of a Torrefaction Process Using Thermal Model Object
Authors: Dhaundiyal Alok , Toth Laszlo
Published: April 2021

So far, the torrefaction process has been merely discussed based on the physical and chemical characteristics of the final product, but the mechanism has not been yet pondered and investigated. Thus far, microwave torrefaction has been predominately used for thermal pre-treatment; therefore, a paradigm shift in the methodology has been introduced by using a Joule heating system. The article mainly focuses on the thermal engineering aspect of the torrefaction process. The densified black pine underwent thermal pre-treatment at a temperature of 523 K. The furnace used for torrefaction was initially improvised to carry out thermal degradation at quasi-static/dynamic conditions. A 3D PDE thermal model was developed to determine the numerical solution and temperature distribution across a black pine pellet. To compare the effect of the linear ramping profile, time-dependent as well as fixed Dirichlet conditions were applied to the proposed model. The mass distribution, duration of the torrefaction process, the effect of Nusselt and Reynold’s number of inert gas, and thermal history are some of the factors whose influence on the numerical solution was investigated. The simulation of thermal pre-treatment and its effect on the heat transfer characteristic was examined with help of a PDE thermal model, whereas the numerical solution of diffusion of the product of reactions was determined by solving the partial differential equations with the help of the discretisation method (PDEPE). The densification of black pine was performed in a ring die, whereas initial milling of biomass was carried out using a 1.5 mm sieve size. The system was found to have a homogeneous distribution in energy and temperature with time, whereas the amplitude of heat flux along the radial direction was reduced by 15% if the same pellet underwent torrefaction for a duration of 5 min in dynamic mode. Similarly, a 64.46% drop in amplitude of heat flux along the azimuth plane could be seen while performing torrefaction in a time-dependent thermal history. However, the relative amplitude of the heat flux at the centre of the pellet was estimated to be lowered by 98.41% along the vertical axis for heating a pellet in a quasi-static condition. The net change in the mass fraction of carbon dioxide across the boundary film was seen to be 40% higher than that of carbon monoxide. The rate of change of mass fraction of carbon monoxide across the boundary film was increased by 7–11% with the increase in torrefaction time. A 6.8% rise in the evaporation of water was noticed during the first half interval of torrefaction (from 5 min to 10 min). In the second half, from 10 min to 15 min, it was merely increased by 5.8%. A relative drop of 17.24% in water evaporation was estimated in the dynamic state of the system.
The Concept of Safety Management in the Electromobility Development Strategy
Authors: Chruzik Katarzyna , Graboń-Chałupczak Marzena
Published: April 2021

Safety monitoring provides the detection of changes in systems or operations that may suggest any case of approaching a point close to exceeding the acceptable safety standards and indicates whether corrective/prevention actions have been taken. Safety information should be maintained within the scope of transport undertakings to ensure safety and be communicated to all responsible staff, depending on each person’s function in the processes. Regulatory authorities should continuously monitor the implementation of safety management processes and the processes performed by road transport service providers. Safety management, therefore, requires investment in development and modernisation to meet market needs resulting from the mobility of residents, the growth of transport, and the obligations of countries resulting from the transport and environmental policy pursued by the European Union. Along with changes in the transport system, a need to assess their significance for the transport system’s safety arises. Depending on the transport mode (rail, air, water, road), the scope of standardised requirements is quite different each time. The paper analyses the legal requirements and acceptable practices for assessing the significance of the change in all transport modes and develops a standard method for assessing the significance of the change that meets all the requirements of electromobility safety management systems.
Comparison of Tank and Battery Storages for Photovoltaic Water Pumping
Authors: Soenen Camille , Reinbold Vincent , Meunier Simon , Cherni Judith A. , Darga Arouna , Dessante Philippe , Quéval Loïc
Published: April 2021

Photovoltaic water pumping systems (PVWPS) are a promising solution to improve domestic water access in low-income rural areas. It is challenging, however, to make them more affordable for the local communities. We develop here a comparative methodology to assess relevant features of both widely employed PVWPS architecture with water tank storage, and hardly used PVWPS architecture with a battery bank instead of tank storage. The quantitative comparison is carried out through techno-economic optimization, with the goal of minimizing the life cycle cost of PVWPS with constraints on the satisfaction of the water demand of local inhabitants and on the groundwater resource sustainability. It is aimed to support decision-makers in selecting most appropriate storage for domestic water supply projects. We applied the methodology in the rural village of Gogma, Burkina Faso. Results indicate that the life-cycle cost of an optimized PVWPS with batteries is $24.1k while it is $31.1k if a tank is used instead. Moreover, reduced impact on groundwater resources and greater modularity to adapt to evolving water demand is noted if using batteries. However, as batteries must be replaced regularly and recycled adequately, PVWPS’ financial accessibility could increase only if sustainable and efficient operation, maintenance, and recycling facilities for batteries were present or developed locally.
Determination of Water Depth in Ports Using Satellite Data Based on Machine Learning Algorithms
Authors: Mateo-Pérez Vanesa , Corral-Bobadilla Marina , Ortega-Fernández Francisco , Rodríguez-Montequín Vicente
Published: April 2021

One of the fundamental maintenance tasks of ports is the periodic dredging of them. This is necessary to guarantee a minimum draft that will enable ships to access ports safely. The determination of bathymetries is the instrument that determines the need for dredging and permits an analysis of the behavior of the port bottom over time, in order to achieve adequate water depth. Satellite data processing to predict environmental parameters is used increasingly. Based on satellite data and using different machine learning algorithm techniques, this study has sought to estimate the seabed in ports, taking into account the fact that the port areas are strongly anthropized areas. The algorithms that were used were Support Vector Machine (SVM), Random Forest (RF) and the Multi-Adaptive Regression Splines (MARS). The study was carried out in the ports of Candás and Luarca in the Principality of Asturias. In order to validate the results obtained, data was acquired in situ by using a single beam provided. The results show that this type of methodology can be used to estimate coastal bathymetry. However, when deciding which system was best, priority was given to simplicity and robustness. The results of the SVM and RF algorithms outperform those of the MARS. RF performs better in Candás with a mean absolute error (MAE) of 0.27 cm, whereas SVM performs better in Luarca with a mean absolute error of 0.37 cm. It is suggested that this approach is suitable as a simpler and more cost-effective rough resolution alternative, for estimating the depth of turbid water in ports, than single-beam sonar, which is labor-intensive and polluting.
A Modification of the Perturb and Observe Method to Improve the Energy Harvesting of PV Systems under Partial Shading Conditions
Authors: Gil-Velasco Alfredo , Aguilar-Castillo Carlos
Published: April 2021

There are multiples conditions that lead to partial shading conditions (PSC) in photovoltaic systems (PV). Under these conditions, the harvested energy decreases in the PV system. The maximum power point tracking (MPPT) controller aims to harvest the greatest amount of energy even under partial shading conditions. The simplest available MPPT algorithms fail on PSC, whereas the complex ones are effective but require high computational resources and experience in this type of systems. This paper presents a new MPPT algorithm that is simple but effective in tracking the global maximum power point even in PSC. The simulation and experimental results show excellent performance of the proposed algorithm. Additionally, a comparison with a previously proposed algorithm is presented. The comparison shows that the proposal in this paper is faster in tracking the maximum power point than complex algorithms.
Short-Term Load Forecasting Using Encoder-Decoder WaveNet: Application to the French Grid
Authors: Dorado Rueda Fernando , Durán Suárez Jaime , del Real Torres Alejandro
Published: April 2021

The prediction of time series data applied to the energy sector (prediction of renewable energy production, forecasting prosumers’ consumption/generation, forecast of country-level consumption, etc.) has numerous useful applications. Nevertheless, the complexity and non-linear behaviour associated with such kind of energy systems hinder the development of accurate algorithms. In such a context, this paper investigates the use of a state-of-art deep learning architecture in order to perform precise load demand forecasting 24-h-ahead in the whole country of France using RTE data. To this end, the authors propose an encoder-decoder architecture inspired by WaveNet, a deep generative model initially designed by Google DeepMind for raw audio waveforms. WaveNet uses dilated causal convolutions and skip-connection to utilise long-term information. This kind of novel ML architecture presents different advantages regarding other statistical algorithms. On the one hand, the proposed deep learning model’s training process can be parallelized in GPUs, which is an advantage in terms of training times compared to recurrent networks. On the other hand, the model prevents degradations problems (explosions and vanishing gradients) due to the residual connections. In addition, this model can learn from an input sequence to produce a forecast sequence in a one-shot manner. For comparison purposes, a comparative analysis between the most performing state-of-art deep learning models and traditional statistical approaches is presented: Autoregressive-Integrated Moving Average (ARIMA), Long-Short-Term-Memory, Gated-Recurrent-Unit (GRU), Multi-Layer Perceptron (MLP), causal 1D-Convolutional Neural Networks (1D-CNN) and ConvLSTM (Encoder-Decoder). The values of the evaluation indicators reveal that WaveNet exhibits superior performance in both forecasting accuracy and robustness.
Skidders Fuel Consumption in Two Different Working Regions and Types of Forest Management
Authors: Kopseak Hrvoje , Šušnjar Marijan , Bačić Marin , Šporčić Mario , Pandur Zdravko
Published: April 2021

For the needs of fuel consumption analysis, a database for a period of 2 years was created for three types of skidders operating in two different management methods—even-aged and selective forests. A total of 436 skidders were processed in the database, of which 255 skidders worked in even-aged forests and 181 skidders worked in selective forests. The average consumption of skidders in even-aged forests ranged from 1.38 to 1.65 L/m3 or from 7.81 to 9.34 L/PMH, while in selective forests, the average consumption ranged from 1.06 to 1.34 L/m3 or from 6.49 to 7.10 L/PMH. The obtained results indicate higher fuel consumption for all three types of skidders in regular forest management. There is no statistically significant difference in fuel consumption between the studied skidders. Comparing fuel consumption in L/PMH, we notice that there was an increase in fuel consumption in relation to the age of the skidder.
Natural Seed Limitation and Effectiveness of Forest Plantations to Restore Semiarid Abandoned Metal Mining Areas in SE Spain
Authors: Oná Marta Bindang , Goberna Marta , Navarro-Cano Jose Antonio
Published: April 2021

The natural regeneration of forests in mining areas is typically hampered by edaphic stress. Semiarid conditions add a climatic stress that challenges the restoration of these harsh ecosystems. This is the case of Tetraclinisarticulata (Vahl) Masters mixed forests in the Western Mediterranean region colonizing mining structures abandoned three decades ago. We studied the factors controlling the natural establishment of nine shrub and tree species key in these forests in eight metal mine tailings in SE Spain. In addition, we assessed the success of reintroducing 1480 individuals of the nine species 15 months after planting in one of the tailings. Specifically, we analyzed the effect of (i) species identity in terms of sapling survival, growth, nutritional status and metal bioaccumulation, and (ii) adding organic amendments into the planting holes on the same parameters. Our results indicated that natural colonization is a recent process, with seedling cohorts that vary up to two orders of magnitude among species and a practical absence of adult plants in most species excepting T. articulata. We identified seed limitation as a key factor controlling seedling density, which was significantly explained by the distance from the border of the tailing to the closest adult out of the tailing. Soil metal concentration did not have any explanatory power on the density of naturally-established seedlings, whereas soil fertility was relevant only for Rhamnus lycioides L. Overall survival of planted individuals was over 80%, survival and growth remarkably differing among species. Organic amendments had neutral or negative effects on plant survival, but significantly increased the growth of survivors despite their modest effects on leaf nutrient contents. Most species showed high metal bioaccumulation, which was exacerbated by organic amendments. We discuss how biodiversity conservation programs can benefit from the affordable and successful plantation of stress-tolerant local species, but come at the expense of potential metal transfer through trophic webs.
Disentangling the Ecological Determinants of Species and Functional Trait Diversity in Herb-Layer Plant Communities in European Temperate Forests
Authors: Kermavnar Janez , Kutnar Lado , Marinšek Aleksander
Published: April 2021

Forest herb-layer vegetation responds sensitively to environmental conditions. This paper compares drivers of both taxonomic, i.e., species richness, cover and evenness, and functional herb-layer diversity, i.e., the diversity of clonal, bud bank and leaf-height-seed plant traits. We investigated the dependence of herb-layer diversity on ecological determinants related to soil properties, climatic parameters, forest stand characteristics, and topographic and abiotic and biotic factors associated with forest floor structure. The study was conducted in different forest types in Slovenia, using vegetation and environmental data from 50 monitoring plots (400 m2 each) belonging to the ICP Forests Level I and II network. The main objective was to first identify significant ecological predictors and then quantify their relative importance. Species richness was strongly determined by forest stand characteristics, such as richness of the shrub layer, tree layer shade-casting ability as a proxy for light availability and tree species composition. It showed a clear positive relation to soil pH. Variation in herb-layer cover was also best explained by forest stand characteristics and, to a lesser extent, by structural factors such as moss cover. Species evenness was associated with tree species composition, shrub layer cover and soil pH. Various ecological determinants were decisive for the diversity of below-ground traits, i.e., clonal and bud bank traits. For these two trait groups we observed a substantial climatic signal that was completely absent for taxonomy-based measures of diversity. In contrast, above-ground leaf-height-seed (LHS) traits were driven exclusively by soil reaction and nitrogen availability. In synthesis, local stand characteristics and soil properties acted as the main controlling factors for both species and trait diversity in herb-layer communities across Slovenia, confirming many previous studies. Our findings suggest that the taxonomic and functional facets of herb-layer vegetation are mainly influenced by a similar set of ecological determinants. However, their relative importance varies among individual taxonomy- and functional trait-based diversity measures. Integrating multi-faceted approaches can provide complementary information on patterns of herb-layer diversity in European forest plant communities.
Effect of the Addition of Non-Saccharomyces at First Alcoholic Fermentation on the Enological Characteristics of Cava Wines
Authors: Mislata Ana María , Puxeu Miquel , Andorrà Immaculada , Espligares Noelia , de Lamo Sergi , Mestres Montserrat , Ferrer-Gallego Raúl
Published: April 2021

Background: Cava is considered to be a high-quality wine internationally. Hence, it has undergone consistent improvement and/or the preservation of its aromatic qualities, bouquet, color, and foamability, throughout its elaboration and aging. Methods: This study investigates the use of different Saccharomyces and non-Saccharomyces yeasts strains (Torulaspora delbrueckii and Metschnikowia pulcherrima) in Chardonnay and Xarel.lo cava wines. The usual enological parameters, the volatile composition, the protein contents, and foamability were determined, and sensory analyses were also performed for all of the vinifications (both before tirage and after 18 months of aging on the lees). Results: the protein and foamability results show that there is a direct relationship between both parameters, with better foam persistence achieved in some non-Saccharomyces fermentation. M. pulcherrima base wines showed a high protein content, improving foamability and foaming persistence. In addition, the results of the aromatic composition and the sensory analysis showed that the use of T. delbrueckii at first fermentation produced interesting cavas from an aromatic perspective. These cavas showed the highest values of ethyl isovalerate (120–126 µg/L), providing aromatic fruity notes, especially fresh green apple. Conclusions: the use of non-Saccharomyces yeasts in the base wine fermentation can be an alternative to produce cavas with differentiated aromatic characteristics and interesting foaming ability.
How Schools Affected the COVID-19 Pandemic in Italy: Data Analysis for Lombardy Region, Campania Region, and Emilia Region
Authors: Tosi Davide , Campi Alessandro Siro
Published: April 2021

Background: Coronavirus Disease 2019 (COVID-19) is the main discussed topic worldwide in 2020 and at the beginning of the Italian epidemic, scientists tried to understand the virus diffusion and the epidemic curve of positive cases with controversial findings and numbers. Objectives: In this paper, a data analytics study on the diffusion of COVID-19 in Lombardy Region and Campania Region is developed in order to identify the driver that sparked the second wave in Italy. Methods: Starting from all the available official data collected about the diffusion of COVID-19, we analyzed Google mobility data, school data and infection data for two big regions in Italy: Lombardy Region and Campania Region, which adopted two different approaches in opening and closing schools. To reinforce our findings, we also extended the analysis to the Emilia Romagna Region. Results: The paper shows how different policies adopted in school opening/closing may have had an impact on the COVID-19 spread, while other factors related to citizen mobility did not affect the second Italian wave. Conclusions: The paper shows that a clear correlation exists between the school contagion and the subsequent temporal overall contagion in a geographical area. Moreover, it is clear that highly populated provinces have the greatest spread of the virus.
Evaluation of Quality and Storability of “Italia” Table Grapes Kept on the Vine in Comparison to Cold Storage Techniques
Authors: Piazzolla Francesca , Amodio Maria Luisa , Pati Sandra , Colelli Giancarlo
Published: April 2021

The aim of the study was to compare the quality of table grapes (cv. Italia) held on the vine compared to grapes stored in cold rooms with or without modified-atmosphere packaging (MAP). The grapes were harvested from 12 plants in 2 vineyards in the same area, differing for the age of the plant. Four- and a fourteen-year-old vines were cultivated with the “Apulia tendone” system. After the first harvest, grapes were divided into small clusters and used for storage treatments in air and in MAP. Samples of 400 g were packaged in polypropylene (PP) trays sealed with a polypropylene/polyamide (PP/PA) film with 20% CO2 in air. MAP and control samples were then stored in the same cold room at 0 °C. Initially and after 8, 21, and 28 days, grapes stored in air and MAP were compared to fresh harvested grapes, stored on the plants. Quality attributes included color, texture, maturity index, phenols, antioxidant activity, sugars, organic acids, sensory parameters, and volatile compounds. The results obtained demonstrated that grapes held on the plant and in MAP showed better quality in terms of appearance scores compared to grapes stored in air. In particular, the application of high CO2 contributed to reduce the deterioration rate of the clusters, minimizing weight loss, and delaying degradation processes, and this particularly for grapes from the 14-year-old vine, where grapes held on the plant degraded faster than grapes in the younger vines. Most volatile compounds did not change their concentration with the storage treatment, except for ethyl acetate and ethanol, which increased in MAP at the end of storage, and to some compound responsible for green odor. In conclusion, keeping the grapes on the plant can be considered a good agronomic practice to preserve the quality, whereas MAP can be applied to better maintain postharvest quality of the product throughout storage and distribution.
A Nonsense Variant in Hephaestin Like 1 (HEPHL1) Is Responsible for Congenital Hypotrichosis in Belted Galloway Cattle
Authors: Kuca Thibaud , Marron Brandy M. , Jacinto Joana G. P. , Paris Julia M. , Gerspach Christian , Beever Jonathan E. , Drögemüller Cord
Published: April 2021

Genodermatosis such as hair disorders mostly follow a monogenic mode of inheritance. Congenital hypotrichosis (HY) belong to this group of disorders and is characterized by abnormally reduced hair since birth. The purpose of this study was to characterize the clinical phenotype of a breed-specific non-syndromic form of HY in Belted Galloway cattle and to identify the causative genetic variant for this recessive disorder. An affected calf born in Switzerland presented with multiple small to large areas of alopecia on the limbs and on the dorsal part of the head, neck, and back. A genome-wide association study using Swiss and US Belted Galloway cattle encompassing 12 cases and 61 controls revealed an association signal on chromosome 29. Homozygosity mapping in a subset of cases refined the HY locus to a 1.5 Mb critical interval and subsequent Sanger sequencing of protein-coding exons of positional candidate genes revealed a stop gain variant in the HEPHL1 gene that encodes a multi-copper ferroxidase protein so-called hephaestin like 1 (c.1684A>T; p.Lys562*). A perfect concordance between the homozygous presence of this most likely pathogenic loss-of-function variant and the HY phenotype was found. Genotyping of more than 700 purebred Swiss and US Belted Galloway cattle showed the global spread of the mutation. This study provides a molecular test that will permit the avoidance of risk matings by systematic genotyping of relevant breeding animals. This rare recessive HEPHL1-related form of hypotrichosis provides a novel large animal model for similar human conditions. The results have been incorporated in the Online Mendelian Inheritance in Animals (OMIA) database (OMIA 002230-9913).
Species-Specific Quality Control, Assembly and Contamination Detection in Microbial Isolate Sequences with AQUAMIS
Authors: Deneke Carlus , Brendebach Holger , Uelze Laura , Borowiak Maria , Malorny Burkhard , Tausch Simon H.
Published: April 2021

Sequencing of whole microbial genomes has become a standard procedure for cluster detection, source tracking, outbreak investigation and surveillance of many microorganisms. An increasing number of laboratories are currently in a transition phase from classical methods towards next generation sequencing, generating unprecedented amounts of data. Since the precision of downstream analyses depends significantly on the quality of raw data generated on the sequencing instrument, a comprehensive, meaningful primary quality control is indispensable. Here, we present AQUAMIS, a Snakemake workflow for an extensive quality control and assembly of raw Illumina sequencing data, allowing laboratories to automatize the initial analysis of their microbial whole-genome sequencing data. AQUAMIS performs all steps of primary sequence analysis, consisting of read trimming, read quality control (QC), taxonomic classification, de-novo assembly, reference identification, assembly QC and contamination detection, both on the read and assembly level. The results are visualized in an interactive HTML report including species-specific QC thresholds, allowing non-bioinformaticians to assess the quality of sequencing experiments at a glance. All results are also available as a standard-compliant JSON file, facilitating easy downstream analyses and data exchange. We have applied AQUAMIS to analyze ~13,000 microbial isolates as well as ~1000 in-silico contaminated datasets, proving the workflow’s ability to perform in high throughput routine sequencing environments and reliably predict contaminations. We found that intergenus and intragenus contaminations can be detected most accurately using a combination of different QC metrics available within AQUAMIS.
Non-Specific Binding, a Limitation of the Immunofluorescence Method to Study Macrophages In Situ
Authors: Sicherre Emma , Favier Anne-Laure , Riccobono Diane , Nikovics Krisztina
Published: April 2021

Advances in understanding tissue regenerative mechanisms require the characterization of in vivo macrophages as those play a fundamental role in this process. This characterization can be approached using the immuno-fluorescence method with widely studied and used pan-markers such as CD206 protein. This work investigated CD206 expression in an irradiated-muscle pig model using three different antibodies. Surprisingly, the expression pattern during immunodetection differed depending on the antibody origin and could give some false results. False results are rarely described in the literature, but this information is essential for scientists who need to characterize macrophages. In this context, we showed that in situ hybridization coupled with hybridization-chain-reaction detection (HCR) is an excellent alternative method to detect macrophages in situ.
Evaluation of RT-qPCR and Loop-Mediated Isothermal Amplification (LAMP) Assays for the Detection of SARS-CoV-2 in Argentina
Authors: Fellner María Dolores , Bonaventura Romina , Basiletti Jorge , Avaro Martín , Benedetti Estefanía , Campos Ana , Dattero María Elena , Russo Mara , Vladmirsky Sara , Molina Viviana , Irazu Lucía , Rodriguez Marcelo A. , Pontoriero Andrea , Cisterna Daniel M. , Baumeister Elsa G.
Published: April 2021

Our aim was to evaluate the analytical and clinical performance of the SARS-CoV-2 molecular detection kits used in Argentina. Nine real-time reverse-transcription polymerase chain reaction (RT-qPCR) and three reverse-transcription loop-mediated isothermal amplification (RT-LAMP) assays were evaluated using the World Health Organization (WHO) recommended test as reference method. A secondary standard calibrated for the E, N and RdRp genes against the Pan American Health Organization—World Health Organization—International Standard was used to calculate the limit of detection (LoD). A panel of artificial clinical samples, 32 positive and 30 negative for SARS-CoV-2, were analyzed to estimate the kappa concordance (κ) and the diagnostic performance. Differences among the LoD values for the target genes amplified by each kit were >1 log copies/reaction. The κ for the RT-qPCR kits was greater than 0.9, whereas that for the RT-LAMP assays ranged from 0.75 to 0.93. The clinical performance of RT-qPCR kits showed 100% specificity and high sensitivity, although with variations according to the gene analyzed. The E and N genes provided greater clinical sensitivity, whereas the RdRp gene increased the clinical specificity. The RT-LAMP assays revealed a variable diagnostic performance. The information provided can be useful to choose the most appropriate diagnostic test and may contribute to the establishment of a consensus in the diagnosis of SARS-CoV-2 in Argentina and the region.
Regulatory Role of Orexin in the Antistress Effect of “Press Tack Needle” Acupuncture Treatment
Authors: Fujiwara Aki , Tsukada Mana , Ikemoto Hideshi , Izuno Takuji , Hattori Satoshi , Okumo Takayuki , Hisamitsu Tadashi , Sunagawa Masataka
Published: April 2021

The aim of this research was to investigate the antistress effect of press tack needle (PTN) acupuncture treatment using rats with social isolation stress (SIS). Rats were divided into non-stress group (Grouped+sham), stress group (SIS+sham), and PTN-treated SIS group (SIS+PTN). Rats in the SIS+PTN and SIS+sham groups were housed alone for eight days. For the SIS+PTN group, a PTN (length, 0.3 or 1.2 mm) was fixed on the GV20 acupoint on day 7. We measured stress behavior based on the time the rats showed aggressive behavior and the levels of plasma corticosterone and orexin A on day 8. In addition, the orexin-1 receptor or orexin-2 receptor antagonist was administered to rats that were exposed to SIS. The duration of aggressive behavior was significantly prolonged in the SIS+sham group, and the prolonged duration was inhibited in the SIS+PTN (1.2 mm) group. The levels of plasma corticosterone and orexin A were significantly increased in the SIS+sham group; however, these increases were inhibited in the SIS+PTN group. The aggressive behavior was significantly reduced after the orexin-2 receptor antagonist was administered. These findings suggest that PTN treatment at GV20 may have an antistress effect, and the control of orexin is a mechanism underlying this phenomenon.