bluuebunny/crossref_metadata_2025 huggingface dataset:
Scintillation and Energy-Storage Properties of Micro-Pulling-Down Grown Crystals of Sc3+- and La3+-Doped YAlO3 Perovskite
Authors: Gieszczyk Wojciech , Mrozik Anna , Bilski Paweł , Vistovskyy Vitaliy , Voloshinovskii Anatoliy , Paprocki Kazimierz , Zorenko Tetiana , Zorenko Yuriy
Published: May 2020

The scintillation and energy-storage properties of YAlO3 (YAP) crystals doped with Sc3+ and La3+ isoelectronic dopants were investigated in this work. The YAP:Sc and YAP:La crystals were grown from the melt with a nominal Sc and La content in the 0.2–5.0 mol.% range using the novel micro-pulling-down method. We found that the segregation coefficient of Sc ions in YAP:Sc (0.2–1.0 mol.%) crystals is about of 0.35–0.4 and decreases to around 0.2 at Sc content of 5.0 mol.% when the segregation coefficient of La ions in YAP:La (1.0–5.0 mol.%) crystals is 0.008–0.01. The scintillation and stimulated luminescence phenomena, like thermo- and photoluminescence, were utilized for the property characterization of the studied materials. The cathodoluminescence and X-ray-excited luminescence were used for the imitation of scintillation in the YAP:Sc and YAP:La crystals. The influence of Sc3+ and La3+ dopant concentration on the CL and RL emission spectra, as well as the shape of the measured thermoluminescence (TL) glow-curves, was also investigated. The measured emission spectra showed dominant emission of Sc3+ and La3+ ions in the UV range. For this reason, the YAP:Sc and YAP:La crystals can be considered for creation of ultraviolet (UV)-emitting scintillators. For the undoped YAlO3 crystals, the main TL emission peak occurs in a low-temperature range at 375 K. Meanwhile, even a small addition of dopants causes a strong suppression of luminescence of the YAP host and high-temperature peaks become dominant in the TL glow-curves of YAP:Sc and YAP:La crystals. Moreover, the amplitude of emission does not change monotonically with increasing dopant content. The kinetic parameters of emission were also evaluated, and the first-order behavior was confirmed in all cases. The dosimetric properties of investigated materials such as dose response, fading rate, and the lowest measurable dose are also discussed. The obtained results tend to suggest that the YAlO3 perovskite host, apart from its application for the development of efficient scintillators, may also be considered as a promising matrix for the creation of energy-storage phosphors for dosimetric applications.
Morphological Convergence and Divergence in Galaxias Fishes in Lentic and Lotic Habitats
Authors: Dunn Nicholas R. , O’Brien Leanne K. , Burridge Christopher P. , Closs Gerard P.
Published: May 2020

The influence of contrasting lentic and lotic hydrological environments on the morphology of members of the Galaxias vulgaris species complex was examined. Morphological variation between habitat types was investigated by comparison of populations of Galaxias brevipinnis (inferred ancestor), Galaxias gollumoides (roundhead morphotype) and Galaxias vulgaris (flathead morphotype). Interspecific convergence and intraspecific divergence of morphological characters were demonstrated, representing general shifts in morphology towards a common functional form in particular hydrological environments. In all species, more lentic Galaxias had longer bodies; shorter, more stout caudal peduncles; longer, narrower pectoral fins; and longer, wider heads with larger mouths. In comparison, lotic Galaxias had relatively shorter bodies; more slender caudal peduncles; broader pectoral fins; and shorter flatter heads, with smaller mouths. This study suggests that the hydrological environment of a habitat is an important factor moulding and maintaining an individual fish’s morphology to a particular habitat type, most likely representing a phenotypic plastic response.
A New Genus of Terrestrial-Breeding Frogs (Holoadeninae, Strabomantidae, Terrarana) from Southern Peru
Authors: Catenazzi Alessandro , Mamani Luis , Lehr Edgar , von May Rudolf
Published: May 2020

We propose to erect a new genus of terrestrial-breeding frogs of the Terrarana clade to accommodate three species from the Province La Convención, Department of Cusco, Peru previously assigned to Bryophryne: B. flammiventris, B. gymnotis, and B. mancoinca. We examined types and specimens of most species, reviewed morphological and bioacoustic characteristics, and performed molecular analyses on the largest phylogeny of Bryophryne species to date. We performed phylogenetic analysis of a dataset of concatenated sequences from fragments of the 16S rRNA and 12S rRNA genes, the protein-coding gene cytochrome c oxidase subunit I (COI), the nuclear protein-coding gene recombination-activating protein 1 (RAG1), and the tyrosinase precursor (Tyr). The three species are immediately distinguishable from all other species of Bryophryne by the presence of a tympanic membrane and annulus, and by males having median subgular vocal sacs and emitting advertisement calls. Our molecular phylogeny confirms that the three species belong to a new, distinct clade, which we name Qosqophryne, and that they are reciprocally monophyletic with species of Microkayla. These two genera (Qosqophryne and Microkayla) are more closely related to species of Noblella and Psychrophrynella than to species of Bryophryne. Although there are no known morphological synapomorphies for either Microkayla or Qosqophryne, the high endemism of their species, and the disjoint geographic distribution of the two genera, with a gap region of ~310 km by airline where both genera are absent, provide further support for Qosqophryne having long diverged from Microkayla. The exploration of high elevation moss and leaf litter habitats in the tropical Andes will contribute to increase knowledge of the diversity and phylogenetic relationships within Terrarana.
Design and Realization of an Aviation Computer Micro System Based on SiP
Authors: Lv Hao , Zhang Shengbing , Han Wei , Liu Yongqiang , Liu Shuo , Chu Yaoqin , Zhang Lei
Published: May 2020

In recent years, microelectronics technology has entered the era of nanoelectronics/integrated microsystems. System in Package (SiP) and System on Chip (SoC) are two important technical approaches for microsystems. The development of micro-system technology has made it possible to miniaturize airborne and missile-borne electronic equipment. This paper introduces the design and implementation of an aerospace miniaturized computer system. The SiP chip uses Xilinx Zynq® SoC (2ARM® + FPGA), FLASH memory and DDR3 memory as the main components, and integrates with SiP high-density system packaging technology. The chip has the advantages of small size and ultra-low power consumption compared with the traditional PCB circuit design. A pure software-based DDR3 signal eye diagram test method is used to verify the improvement inf the signal integrity of the chip without the need for probe measurement. The method of increasing the thermal conductive silver glue was used to improve the thermal performance after the test and analysis. The SiP chip was tested and analyzed with other mainstream aviation computers using a heading measurement of extended Kalman filter (EKF) algorithm. The paper has certain reference value and research significance in the miniaturization of the aviation computer system, the heat dissipation technology of SiP chip and the test method of signal integrity.
Study on Boost Converters with High Power-Density for Hydrogen-Fuel-Cell Hybrid Railway System
Authors: Youn Han-Shin , Yun Duk-Hyeon , Lee Woo-Seok , Lee Il-Oun
Published: May 2020

Step-up DC/DC converters are needed generally for the hydrogen-fuel-cell (HFC) hybrid railway system since the HFC has difficulty directly generating a high link voltage of over 1500 V for the high-power capacity inverter to drive the traction motor in the vehicle. These step-up DC/DC converters demand a high conversion efficiency with low weight and volume, due to the limited space in vehicle. In this paper, step-up DC/DC converters are presented and are evaluated for the HFC hybrid railway system. By choosing the interleaved boost converter and the 3-level boost converter as promising candidates, characteristics and features of both converters are presented through the analysis of the operational principles. In addition, the optimal design methods and results of boost inductor, output capacitor, and power semiconductor devices are presented based on theoretical analysis and a real design specification for the HFC hybrid railway system. Moreover, an optimal digital control design in terms of dynamic current response and reliability, such as current-balance or voltage-balance controls, is presented in this paper. In order to verify the analysis and design results, prototypes of both converters with the 600 V input and 1200 V/20 kW output specifications are constructed and the performance of the interleaved and 3-level boost converters are demonstrated through the experimental results. The experimental results show that the 3-level boost converter is more suitable for the HFC hybrid railway system in the sense of efficiency, power-density, and dynamic current response.
Current Regulator Design for Dual Y Shift 30 Degrees Permanent Magnet Synchronous Motor
Authors: Wu Zhihong , Gu Weisong , Zhu Yuan , Lu Ke , Chen Li , Guan Jianbin
Published: May 2020

This paper gives the current regulator design for a dual Y shift 30 degrees permanent magnet synchronous motor (DT_PMSM) based on the vector space decomposition (VSD). Current regulator design in α-β subspace is insufficient and designing additional controllers in x-y subspace is necessary to eliminate the harmonic currents due to the nonlinear characteristics of the inverter. A sliding mode controller based on an internal model is proposed in α-β subspace, which is robust to the parameter uncertainties and disturbances in current control loops. In order to eliminate the harmonic currents in x-y subspace, a resonant controller is employed based on a new synchronous rotating matrix. Three-phase decomposition space vector pulse width modulation (SVPWM) technique is illustrated for the purpose of synthesizing the voltage vectors in both subspaces simultaneously. The feasibility and efficiency of the suggested current regulator design are validated by a set of experimental results.
Novel Summation-Type Triggering Condition on Event-Based Memory Output Feedback Control for Networked Control Systems
Authors: Kwon Wookyong , Baek Jaemin
Published: May 2020

Networked control systems are widely spread, which is composed of numerous sensor and control nodes through communication channel. In this paper, an event-triggered H ∞ memory output feedback control (EMOFC) is investigated for networked control linear systems in discrete form. The memory control employing memorized past information is exploited to enhance the triggering intervals under event-triggered condition. Moreover, novel summation type event-triggering condition is newly proposed by utilizing buffer memory element. Based upon memory control and novel triggering conditions, the control design methodology is constructed for transformed input-delay model in forms of linear matrix inequalities (LMIs) adopting generalized free-weighting matrix summation inequality. As a result, the proposed scheme shows off the reduction of average signal transmission frequency and reliability while covering standard condition. Throughout numerical examples, the effectiveness is shown and the effect of memory element is analyzed.
Solid State Transformers: Concepts, Classification, and Control
Authors: Shamshuddin Mohammed Azharuddin , Rojas Felix , Cardenas Roberto , Pereda Javier , Diaz Matias , Kennel Ralph
Published: May 2020

Increase in global energy demand and constraints from fossil fuels have encouraged a growing share of renewable energy resources in the utility grid. Accordingly, an increased penetration of direct current (DC) power sources and loads (e.g., solar photovoltaics and electric vehicles) as well as the necessity for active power flow control has been witnessed in the power distribution networks. Passive transformers are susceptible to DC offset and possess no controllability when employed in smart grids. Solid state transformers (SSTs) are identified as a potential solution to modernize and harmonize alternating current (AC) and DC electrical networks and as suitable solutions in applications such as traction, electric ships, and aerospace industry. This paper provides a complete overview on SST: concepts, topologies, classification, power converters, material selection, and key aspects for design criteria and control schemes proposed in the literature. It also proposes a simple terminology to identify and homogenize the large number of definitions and structures currently reported in the literature.
PRISMA Statement for Reporting Literature Searches in Systematic Reviews of the Bioethanol Sector
Authors: Oláh Judit , Krisán Eszter , Kiss Anna , Lakner Zoltán , Popp József
Published: May 2020

The bioethanol sector is an extremely complex set of actors, technologies and market structures, influenced simultaneously by different natural, economic, social and political processes. That is why it lends itself to the application of system dynamics modelling. In last five years a relatively high level of experience and knowledge has accumulated related to the application of computer-aided system modelling for the analysis and forecasting of the bioethanol sector. The goal of the current paper is to offer a systematic review of the application of system dynamics models in order to better understand the structure, conduct and performance of the bioethanol sector. Our method has been the preferred reporting items for systematic reviews and meta-analyses (PRISMA), based on English-language materials published between 2015 and 2020. The results highlight that system dynamic models have become more and more complex, but as a consequence of the improvement in information technology and statistical systems, as well as the increasing experience gained they offer an efficient tool for decision makers in the business and political spheres. In the future, the combination of traditional system dynamics modelling and agent-based models will offer new perspectives for the preparation of more sophisticated description and forecasting.
Measured and Simulated Energy Use in a Secondary School Building in Sweden—A Case Study of Validation, Airing, and Occupancy Behaviour
Authors: Steen Englund Jessika , Cehlin Mathias , Akander Jan , Moshfegh Bahram
Published: May 2020

In this case study, the energy performance of a secondary school building from the 1960s in Gävle, Sweden, was modelled in the building energy simulation (BES) tool IDA ICE version 4.8 prior to major renovation planning. The objectives of the study were to validate the BES model during both occupied and unoccupied periods, investigate how to model airing and varying occupancy behaviour, and finally investigate energy use to identify potential energy-efficiency measures. The BES model was validated by using field measurements and evidence-based input. Thermal bridges, infiltration, mechanical ventilation, domestic hot water circulation losses, and space heating power were calculated and measured. A backcasting method was developed to model heat losses due to airing, opening windows and doors, and other occupancy behaviour through regression analysis between daily heat power and outdoor temperature. Validation results show good agreement: 3.4% discrepancy between space heating measurements and simulations during an unoccupied week. Corresponding monthly discrepancy varied between 5.5% and 10.6% during three months with occupants. Annual simulation indicates that the best potential renovation measures are changing to efficient windows, improved envelope airtightness, new controls of the HVAC system, and increased external wall thermal insulation.
Selection of C-Type Filters for Reactive Power Compensation and Filtration of Higher Harmonics Injected into the Transmission System by Arc Furnaces
Authors: Lange Andrzej Grzegorz , Redlarski Grzegorz
Published: May 2020

This article presents a method for selecting the elements of a C-type filter working with a conventional LC-type filter for compensating reactive power and filtering out higher harmonics generated by arc furnaces and ladle furnaces. The study was conducted in a steel mill supplied by a 110 kV transmission system, where higher harmonic currents and nonlinear loads were measured. A series of computer simulations were performed under various operating conditions, and an algorithm for selecting the parameters of a third-order C-type filter (for suppressing the second harmonic) and two second-order LC-type filters (for suppressing the third harmonic) was proposed. The filtering system was tested in an arc furnace with the highest rated power, and harmonics in the current spectrum were evaluated. The results of the measurements were used to analyze the effectiveness of the compensation system comprising two passive C-type and LC-type filters at different system configurations. C-type filters significantly influenced current harmonics. The influence of the changes in the number of arc furnace transformers on the true Root Mean Square (RMS) of the currents injected into the 110 kV transmission system and on the voltages of the 110 kV busbars was discussed.
Two-Dimensional Tomographic Simultaneous Multi-Species Visualization—Part I: Experimental Methodology and Application to Laminar and Turbulent Flames
Authors: Häber Thomas , Bockhorn Henning , Suntz Rainer
Published: May 2020

In recent years, the tomographic visualization of laminar and turbulent flames has received much attention due to the possibility of observing combustion processes on-line and with high temporal resolution. In most cases, either the spectrally non-resolved flame luminescence or the chemiluminescence of a single species is detected and used for the tomographic reconstruction. In this work, we present a novel 2D emission tomographic setup that allows for the simultaneous detection of multiple species (e.g., OH*, CH* and soot but not limited to these) using a single image intensified CCD camera. We demonstrate the simultaneous detection of OH* (310 nm), CH* (430 nm) and soot (750 nm) in laminar methane/air, as well as turbulent methane/air and ethylene/air diffusion flames. As expected, the reconstructed distributions of OH* and CH* in laminar and turbulent flames are highly correlated, which supports the feasibility of tomographic measurements on these kinds of flames and at timescales down to about 1 ms. In addition, the possibilities and limitations of the tomographic approach to distinguish between locally premixed, partially premixed and non-premixed conditions, based on evaluating the local intensity ratio of OH* and CH* is investigated. While the tomographic measurements allow a qualitative classification of the combustion conditions, a quantitative interpretation of instantaneous reconstructed intensities (single shot results) has a much greater uncertainty.
Modelling Carbon Corrosion during a PEMFC Startup: Simulation of Mitigation Strategies
Authors: Randrianarizafy Bolahaga , Schott Pascal , Gerard Mathias , Bultel Yann
Published: May 2020

This paper presents a study of the carbon support corrosion and mitigation strategies through the use of a pseudo-3D model. This model consists in coupling a 2D model along the channel with another model perpendicular to the flow at the rib/channel scale. Simulations offer a deeper understanding of the corrosion through the analysis of the local conditions. Rib/channel heterogeneities show the higher degradation in the zones facing the anodic rib. These results are validated qualitatively on literature data by analysis of SEM images and carbon dioxide concentration at the cathode outlet. Three mitigation strategies are studied using the model. The first one consists in speeding up the hydrogen filling of the cell. The second strategy involves an external electrical resistance to create a current leak during the startup. Third, a design study of the rib/channel is performed to minimize the cathode degradation. Whatever the mitigation strategy, it consists in reducing either the duration or the magnitude of the high cathode electrode potential.
Estimation of the Energy Consumption of Battery Electric Buses for Public Transport Networks Using Real-World Data and Deep Learning
Authors: Pamuła Teresa , Pamuła Wiesław
Published: May 2020

The estimation of energy consumption is an important prerequisite for planning the required infrastructure for charging and optimising the schedules of battery electric buses used in public urban transport. This paper proposes a model using a reduced number of readily acquired bus trip parameters: arrival times at the bus stops, map positions of the bus stops and a parameter indicating the trip conditions. A deep learning network is developed for deriving the estimates of energy consumption stop by stop of bus lines. Deep learning networks belong to the important group of methods capable of the analysis of large datasets—“big data”. This property allows for the scaling of the method and application to different sized transport networks. Validation of the network is done using real-world data provided by bus authorities of the town of Jaworzno in Poland. The estimates of energy consumption are compared with the results obtained using a regression model that is based on the collected data. Estimation errors do not exceed 7.1% for the set of several thousand bus trips. The study results indicate spots in the public transport network of potential power deficiency which can be alleviated by introducing a charging station or correcting the bus trip schedules.
Storage of Fine Woodchips from a Medium Rotation Coppice Eucalyptus Plantation in Central Italy
Authors: Pari Luigi , Bergonzoli Simone , Cetera Paola , Mattei Paolo , Alfano Vincenzo , Rezaei Negar , Suardi Alessandro , Toscano Giuseppe , Scarfone Antonio
Published: May 2020

Eucalyptus spp. has received attention from the research and industrial field as a biomass crop because of its fast growth and high productivity. The features of this species match with the increasing demand for wood for energy production. Commonly, the wood used for energy production is converted in chips, a material susceptible to microbial degradation and energy losses if not properly stored before conversion. This study aims at investigating two outdoor storage systems of Eucalyptus wood chips (covered vs. uncovered), assessing the variation in moisture content, dry matter losses and fuel characteristics. The class size of the material was P16, which was obtained using a commercial chipper appositely searched to conduct the study. The results highlighted how the different storage methods were influenced by the climatic condition: the woody biomass covered showed the best performances in terms of dry matter losses achieving 2.7% losses vs. the 8.5% of the uncovered systems. However, fuel characteristics displayed minor changes that affected the final energy balance (∆En = −0.2% in covered; ∆En = −6.17% in uncovered). Particle size varied in both methods with respect to the start conditions, but the variation was not enough to determine a class change, which remained P16 even after storage.
Chitosan Oligosaccharide Addition to Buddhist Pine (Podocarpus macrophyllus (Thunb) Sweet) under Drought: Reponses in Ecophysiology and δ13C Abundance
Authors: He Chunxia , Zhao Yan , Zhang Jinsong , Gao Jun
Published: May 2020

Climate warming induces the necessity to increase the drought resistance of shade-obligate juvenile trees in sub-tropical forests. Chitosan oligosaccharide (COS) is a biopolymer derived from the marine resource that has attracted accumulative attention to induce and promote a plant’s resistance to abiotic stress. Buddhist pine (Podocarpus mascrophyllus (Thunb)Sweet) seedlings were cultured as the model material whose natural distribution in sub-tropical areas of China has suffered severe summer drought events in the last 113 years. A split-block design was conducted with a simulated drought event (drought vs. irrigated control), the COS addition, and two samplings at the ends of drought and re-watered treatments. The COS addition increased the resistance to drought by inducing a starch allocation towards roots where δ13C abundance and antioxidant enzyme activities were upregulated. The COS addition can promote biomass allocation to roots and increase the number of new roots. The COS addition to drought-treated Buddhist pine seedlings resulted in robust diameter growth. Therefore, COS is an available polymer to promote the resistance of Buddhist pine to drought. More work is suggested to clarify the dose of COS addition that can induce a prominent response of biomass accumulation and carbohydrate metabolism.
Tree Communities in Three-Year-Old Post-Mining Sites Under Different Forest Restoration Techniques in the Brazilian Amazon
Authors: Conrado da Cruz Denis , Rey Benayas José María , Costa Ferreira Gracialda , Santos Ribeiro Sabrina
Published: May 2020

Forest loss and degradation in the Brazilian Amazon due to mining activities has been intense for many years. To reverse this situation, a range of restoration programs for deforested and degraded areas have been created and implemented. The aim of this study was to analyze the tree composition, successional stage, dispersal and pollination syndromes, conservation status of tree species, and proximity to seed sources under different forest restoration techniques (seedling planting, natural regeneration, and assisted natural regeneration or nucleation) implemented in post-mining sites in the Paragominas municipality (Pará, Brazil). Sixty permanent plots with a restoration age of three years were selected for tree sampling. A total of 119 species, 83 genera and 27 botanical families were identified. Sites restored with different techniques significantly differed in tree composition. Seedling planting sites exhibited the highest abundance, species richness, and diversity values. These were dominated less by pioneer species when compared to the natural regeneration and nucleation sites. Entomophilic pollination and zoochory dispersal were highly represented in the three types of restored sites. Abundance and species richness were negatively correlated with distance from plots to seed sources, and they sharply declined in natural regeneration and nucleation plots at >250 m from seed sources. Four threatened species were identified in the restored sites. We conclude that a combination of different restoration strategies at three-year-old post-mining restoration sites in the Brazilian Amazon results in the recovery of considerable levels of local tree diversity.
A Time Bank System Design on the Basis of Hyperledger Fabric Blockchain
Authors: Lee Yu-Tse , Lin Jhan-Jia , Hsu Jane Yung-Jen , Wu Ja-Ling
Published: May 2020

This paper presents a blockchain-based time bank system on the basis of the Hyperledger Fabric framework, which is one of the permissioned blockchain networks. Most of the services provided by existing Time Bank systems were recorded and conducted manually in the past; furthermore, jobs for matching services with receivers were managed by people. Running a time bank in this way will cost lots of time and human resources and, worse, it lacks security. This work designs and realizes a time bank system enabling all the service-related processes being executed and recorded on a blockchain. The matching between services’ supply-and-demand tasks can directly be done through autonomous smart contracts. Building a time bank system on blockchain benefits the transaction of time credit which plays the role of digital currency on the system. In addition, the proposed time bank also retains a grading system, allowing its members to give each other a grade for reflecting their degrees of satisfaction about the results provided by the system. This grading system will incentivize the members to provide a better quality of service and adopt a nicer attitude for receiving a service, which may positively endorse the development of a worldwide time bank system.
Artificial Intelligence Systems-Aided News and Copyright: Assessing Legal Implications for Journalism Practices
Authors: Díaz-Noci Javier
Published: May 2020

Automated news, or artificial intelligence systems (AIS)-aided production of news items, has been developed from 2010 onwards. It comprises a variety of practices in which the use of data, software and human intervention is involved in diverse degrees. This can affect the application of intellectual property and copyright law in many ways. Using comparative legal methods, we examine the implications of them for some legal categories, such as authorship (and hence required originality) and types of works, namely collaborative, derivative and, most especially, collective works. Sui generis and neighboring rights are also considered for examination as being appliable to AIS-aided news outputs. Our main conclusion is that the economics intellectual property rights are guaranteed in any case through collective works. We propose a shorter term of duration before entering public domain. Still, there is a place for more authorial, personal rights. It shows, however, more difficulty when coming to moral rights, especially in Common Law countries.
Technological Characterisation of Probiotic Lactic Acid Bacteria as Starter Cultures for Dry Fermented Sausages
Authors: Agüero Nadia de L. , Frizzo Laureano S. , Ouwehand Arthur C. , Aleu Gonzalo , Rosmini Marcelo R.
Published: May 2020

The objective of this study was to investigate probiotic microorganisms for use as starter cultures in dry fermented sausages production. A total of eight strains were studied evaluating technological and safety characteristics including the ability to grow, lactic acid production, gas formation, catalase activity, nitrate reductase activity, proteolytic activity, lipolytic activity, hydrogen peroxide production, salt tolerance, performance at low temperatures, decarboxylation of amino acids and antimicrobial activity against pathogens associated with the product. Lactobacillus rhamnosus R0011, L. rhamnosus Lr-32, Lactobacillus paracasei Lpc-37, Lactobacillus casei Shirota and Enterococcus faecium MXVK29 were good candidates for use as fermented sausages starters cultures because they showed the best technological and safety properties since they did not demonstrate amino acid decarboxylation but showed antimicrobial activity against Listeria monocytogenes, Escherichia coli, Salmonella Dublin and Staphylococcus aureus. L. rhamnosus Lr-32 was the strain best tolerating the levels of salt, nitrate and low pH during the simulated stages of fermentation and ripening of sausage. The strain was thus the most promising of the tested probiotics as sausage starter culture. The findings warrant studies in a meat matrix, such as that of raw-cured sausage, to evaluate the effects of L. rhamnosus Lr-32 under actual conditions.
Nutritive and Bioactive Properties of Mesquite (Prosopis pallida) Flour and Its Technological Performance in Breadmaking
Authors: Gonzales-Barron Ursula , Dijkshoorn Rody , Maloncy Maikel , Finimundy Tiane , Calhelha Ricardo C. , Pereira Carla , Stojković Dejan , Soković Marina , Ferreira Isabel C. F. R. , Barros Lillian , Cadavez Vasco
Published: May 2020

Although the nutritional profile, bioactivities, and uses of mesquite pod flour from various Prosopis species have been studied, limited research has been conducted on Prosopis pallida (Humb, & Bonpl. Ex Willd.) Kunth mesquite flour. This study aimed to characterize the nutritional quality and bioactive properties of P. pallida pod flour and to assess its technological performance in breadmaking as a partial replacer of white wheat flour. Peruvian P. pallida mesquite flour was found to have an appealing nutritional profile, with high contents of dietary fiber (29.6% dw) and protein (9.5% dw), and low contents of fat (1.0% dw) and carbohydrates (57.6% dw). It is a source of palmitic (12.6%), oleic (35.5%), and linoleic acids (45.8%), α-, β-, and γ- tocopherols, and contains phenolic compounds such as apigenin glycoside derivatives with proven antioxidant capacities. Extracts of P. pallida flour were also found to have antimicrobial and antifungal effects and did not show hepatoxicity. When formulated as a wheat flour replacer, increasing mesquite flour levels yield composite doughs of lower stickiness and extensibility, and composite breads of lower elasticity (p < 0.01). However, up to a level of 10%, mesquite flour significantly increases loaf volume, reduces crumb hardness, and produces a more uniform crumb of small size alveoli (p < 0.01). Considering the purpose of improving the nutritional and technological quality of wheat flour bread, the addition of P. pallida pod flour can be highly recommended.
Valorisation of Grape Stems as a Source of Phenolic Antioxidants by Using a Sustainable Extraction Methodology
Authors: Nieto Juan Antonio , Santoyo Susana , Prodanov Marin , Reglero Guillermo , Jaime Laura
Published: May 2020

Pressurized liquid extraction with ethanol:water mixtures was proposed for obtaining phenolic antioxidants from grape stems. The optimal extraction conditions were elucidated by using a central composite rotatable design (solvent (X1, 0–100% ethanol:water v/v), temperature (X2, 40–120 °C) and time (X3, 1–11 min)). Response surface methodology determined 30% ethanol:water, 120 °C and 10 min as the optimal extraction conditions regarding total phenolic content (TPC) (185.3 ± 2.9 mg gallic acid/g of extract) and antioxidant activity (3.55 ± 0.21 mmol Trolox/g, 1.22 ± 0.06 mmol Trolox/g and 1.48 ± 0.17 mmol Trolox/g of extract in ABTS, DPPH and ORAC methodologies, respectively). The antioxidant activity was attributed to total polymer procyanidins and flavan-3-ol monomers and oligomers, although other phenolic compound contributions should not be ruled out. Forty-two phenolic compounds were identified in the optimal extract, mainly polymer procyanidins and, to a lesser extent, monomers and oligomers of flavan-3-ols, quercetin-3-O-glucuronide, ε-viniferin, gallic and caftaric acid. Ethyl gallate, ellagic acid, protocatechuic aldehyde, delphinidin-7-O-glucoside and cyanidin-3-O-glucoside were reported for the first time in grape stem extracts. In conclusion, this study highlights the use of this winery side stream as a source of antioxidants within a sustainable food system.
Absence of Strong Genetic Linkage Disequilibrium between Single Nucleotide Polymorphisms (SNPs) in the Prion Protein Gene (PRNP) and the Prion-Like Protein Gene (PRND) in the Horse, a Prion-Resistant Species
Authors: Won Sae-Young , Kim Yong-Chan , Do Kyoungtag , Jeong Byung-Hoon
Published: May 2020

Prion disease is a fatal neurodegenerative disorder caused by a deleterious prion protein (PrPSc). However, prion disease has not been reported in horses during outbreaks of transmissible spongiform encephalopathies (TSEs) in various animals in the UK. In previous studies, single nucleotide polymorphisms (SNPs) in the prion protein gene (PRNP) have been significantly associated with susceptibility to prion disease, and strong linkage disequilibrium (LD) between PRNP and prion-like protein gene (PRND) SNPs has been identified in prion disease-susceptible species. On the other hand, weak LD values have been reported in dogs, a prion disease-resistant species. In this study, we investigated SNPs in the PRND gene and measured the LD values between the PRNP and PRND SNPs and the impact of a nonsynonymous SNP found in the horse PRND gene. To identify SNPs in the PRND gene, we performed direct sequencing of the PRND gene. In addition, to assess whether the weak LD value between the PRNP and PRND SNPs is a characteristic of prion disease-resistant animals, we measured the LD value between the PRNP and PRND SNPs using D’ and r2 values. Furthermore, we evaluated the impact of a nonsynonymous SNP in the Doppel protein with PolyPhen-2, PROVEAN, and PANTHER. We observed two novel SNPs, c.331G > A (A111T) and c.411G > C. The genotype and allele frequencies of the c.331G > A (A111T) and c.411G > C SNPs were significantly different between Jeju, Halla, and Thoroughbred horses. In addition, we found a total of three haplotypes: GG, AG, and GC. The GG haplotype was the most frequently observed in Jeju and Halla horses. Furthermore, the impact of A111T on the Doppel protein was predicted to be benign by PolyPhen-2, PROVEAN, and PANTHER. Interestingly, a weak LD value between the PRNP and PRND SNPs was found in the horse, a prion disease-resistant animal. To the best of our knowledge, these results suggest that a weak LD value could be one feature of prion disease-resistant animals.
Dynamic Transcriptome Analysis Reveals Uncharacterized Complex Regulatory Pathway Underlying Genotype-Recalcitrant Somatic Embryogenesis Transdifferentiation in Cotton
Authors: Guo Huihui , Guo Haixia , Zhang Li , Fan Yijie , Wu Jianfei , Tang Zhengmin , Zhang Yao , Fan Yupeng , Zeng Fanchang
Published: May 2020

As a notable illustration of totipotency and plant regeneration, somatic embryogenesis (SE) is the developmental reprogramming of somatic cells toward the embryogenesis pathway, the key step for genetic engineering. Investigations examining the totipotency process are of great fundamental and practical importance in crop biotechnology. However, high-frequency regeneration of cotton via SE has been limited due to genotype-dependent response. The molecular basis deciphering SE genotype recalcitrance remains largely unexplored in cotton. In the current study, to comprehensively investigate the dynamic transcriptional profiling and gene regulatory patterns involved in SE process, a genome-wide RNA sequencing analysis was performed in two cotton genotypes with distinct embryogenic abilities, the highly embryogenic genotype Yuzao 1 (YZ) and the recalcitrant genotype Lumian 1 (LM). Three typical developmental staged cultures of early SE—hypocotyls (HY), nonembryogenic calli (NEC) and primary embryogenic calli (PEC)—were selected to establish the transcriptional profiles. Our data revealed that a total of 62,562 transcripts were present amongst different developmental stages in the two genotypes. Of these, 18,394 and 26,514 differentially expressed genes (DEGs) were identified during callus dedifferentiation (NEC-VS-HY) and embryogenic transdifferentiation (PEC-VS-NEC), respectively in the recalcitrant genotype, 21,842 and 22,343 DEGs in the highly embryogenic genotype. Furthermore, DEGs were clustered into six expression patterns during cotton SE process in the two genotypes. Moreover, functional enrichment analysis revealed that DEGs were significantly enriched in fatty acid, tryptophan and pyruvate metabolism in the highly embryogenic genotype and in DNA conformation change otherwise in the recalcitrant genotype. In addition, critical SE-associated expressed transcription factors, as well as alternative splicing events, were notably and preferentially activated during embryogenic transdifferentiation in the highly embryogenic genotype compared with the recalcitrant genotype. Taken together, by systematically comparing two genotypes with distinct embryogenic abilities, the findings in our study revealed a comprehensive overview of the dynamic gene regulatory patterns and uncharacterized complex regulatory pathways during cotton SE genotype-dependent response. Our work provides insights into the molecular basis and important gene resources for understanding the underlying genotype recalcitrance during SE process and plant regeneration, thereby holding great promise for accelerating the application of biotechnology to cotton for improving its breeding efficiency.
Cellular Environment Remodels the Genomic Fabrics of Functional Pathways in Astrocytes
Authors: Iacobas Dumitru A , Iacobas Sanda , Stout Randy F , Spray David C
Published: May 2020

We profiled the transcriptomes of primary mouse cortical astrocytes cultured alone or co-cultured with immortalized precursor oligodendrocytes (Oli-neu cells). Filters between the cell types prevented formation of hetero-cellular gap junction channels but allowed for free exchange of the two culture media. We previously reported that major functional pathways in the Oli-neu cells are remodeled by the proximity of non-touching astrocytes and that astrocytes and oligodendrocytes form a panglial transcriptomic syncytium in the brain. Here, we present evidence that the astrocyte transcriptome likewise changes significantly in the proximity of non-touching Oli-neu cells. Our results indicate that the cellular environment strongly modulates the transcriptome of each cell type and that integration in a heterocellular tissue changes not only the expression profile but also the expression control and networking of the genes in each cell phenotype. The significant decrease of the overall transcription control suggests that in the co-culture astrocytes are closer to their normal conditions from the brain. The Oli-neu secretome regulates astrocyte genes known to modulate neuronal synaptic transmission and remodels calcium, chemokine, NOD-like receptor, PI3K-Akt, and thyroid hormone signaling, as well as actin-cytoskeleton, autophagy, cell cycle, and circadian rhythm pathways. Moreover, the co-culture significantly changes the gene hierarchy in the astrocytes.
A Minimal Genetic Passkey to Unlock Many Legume Doors to Root Nodulation by Rhizobia
Authors: Unay Jovelyn , Perret Xavier
Published: May 2020

In legume crops, formation of developmentally mature nodules is a prerequisite for efficient nitrogen fixation by populations of rhizobial bacteroids established inside nodule cells. Development of root nodules, and concomitant microbial colonization of plant cells, are constrained by sets of recognition signals exchanged by infecting rhizobia and their legume hosts, with much of the specificity of symbiotic interactions being determined by the flavonoid cocktails released by legume roots and the strain-specific nodulation factors (NFs) secreted by rhizobia. Hence, much of Sinorhizobium fredii strain NGR234 symbiotic promiscuity was thought to stem from a family of >80 structurally diverse NFs and associated nodulation keys in the form of secreted effector proteins and rhamnose-rich surface polysaccharides. Here, we show instead that a mini-symbiotic plasmid (pMiniSym2) carrying only the nodABCIJ, nodS and nodD1 genes of NGR234 conferred promiscuous nodulation to ANU265, a derivative strain cured of the large symbiotic plasmid pNGR234a. The ANU265::pMiniSym2 transconjugant triggered nodulation responses on 12 of the 22 legumes we tested. On roots of Macroptilium atropurpureum, Leucaena leucocephala and Vigna unguiculata, ANU265::pMiniSym2 formed mature-like nodule and successfully infected nodule cells. While cowpea and siratro responded to nodule colonization with defense responses that eventually eliminated bacteria, L. leucocephala formed leghemoglobin-containing mature-like nodules inside which the pMiniSym2 transconjugant established persistent intracellular colonies. These data show seven nodulation genes of NGR234 suffice to trigger nodule formation on roots of many hosts and to establish chronic infections in Leucaena cells.
Cytogenetic Mapping of 35 New Markers in the Alpaca (Vicugna pacos)
Authors: Mendoza Mayra N. , Raudsepp Terje , More Manuel J. , Gutiérrez Gustavo A. , Ponce de León F. Abel
Published: May 2020

Alpaca is a camelid species of broad economic, biological and biomedical interest, and an essential part of the cultural and historical heritage of Peru. Recently, efforts have been made to improve knowledge of the alpaca genome, and its genetics and cytogenetics, to develop molecular tools for selection and breeding. Here, we report cytogenetic mapping of 35 new markers to 19 alpaca autosomes and the X chromosome. Twenty-eight markers represent alpaca SNPs, of which 17 are located inside or near protein-coding genes, two are in ncRNA genes and nine are intergenic. The remaining seven markers correspond to candidate genes for fiber characteristics (BMP4, COL1A2, GLI1, SFRP4), coat color (TYR) and development (CHD7, PAX7). The results take the tally of cytogenetically mapped markers in alpaca to 281, covering all 36 autosomes and the sex chromosomes. The new map assignments overall agree with human–camelid conserved synteny data, except for mapping BMP4 to VPA3, suggesting a hitherto unknown homology with HSA14. The findings validate, refine and correct the current alpaca assembly VicPac3.1 by anchoring unassigned sequence scaffolds, and ordering and orienting assigned scaffolds. The study contributes to the improvement in the alpaca reference genome and advances camelid molecular cytogenetics.
Comparative Analysis of the Minimum Number of Replication Origins in Trypanosomatids and Yeasts
Authors: da Silva Marcelo S. , O. Vitarelli Marcela , F. Souza Bruno , Elias Maria Carolina
Published: May 2020

Single-celled eukaryote genomes predominantly replicate through multiple origins. Although origin usage during the S-phase has been elucidated in some of these organisms, few studies have comparatively approached this dynamic. Here, we developed a user-friendly website able to calculate the length of the cell cycle phases for any organism. Next, using a formula developed by our group, we showed a comparative analysis among the minimum number of replication origins (MO) required to duplicate an entire chromosome within the S-phase duration in trypanosomatids (Trypanosoma cruzi, Leishmania major, and Trypanosoma brucei) and yeasts (Saccharomyces cerevisiae and Schizosaccharomyces pombe). Using the data obtained by our analysis, it was possible to predict the MO required in a situation of replication stress. Also, our findings allow establishing a threshold for the number of origins, which serves as a parameter for genome approaches that map origins. Moreover, our data suggest that when compared to yeasts, trypanosomatids use much more origins than the minimum needed. This is the first time a comparative analysis of the minimum number of origins has been successfully applied. These data may provide new insight into the understanding of the replication mechanism and a new methodological framework for studying single-celled eukaryote genomes.
Genotype-Phenotype Correlation: A Triple DNA Mutational Event in a Boy Entering Sport Conveys an Additional Pathogenicity Risk
Authors: Limongelli Giuseppe , Nunziato Marcella , Mazzaccara Cristina , Intrieri Mariano , D’Argenio Valeria , Esposito Maria Valeria , Monda Emanuele , Di Maggio Federica , Frisso Giulia , Salvatore Francesco
Published: May 2020

The purpose of this paper is to present a clinical and laboratory study of a family, in which a 12-year-old boy was examined to assess his health status before starting competitive sports. A variety of clinical and instrumental tests were used to evaluate the status of the heart and its functions. Using Sanger sequencing (SS), we sequenced six related genes to verify suspected arrhythmogenic right ventricular cardiomyopathy (ARVC) hypothesized at the cardiac assessment and, subsequently, by a next-generation sequencing (NGS)-based multi-gene panel for more paramount genetic risk of sudden cardiac death (SCD) assessment. SS revealed two variants in the PKP2 gene, one was inherited from the father and the other from the mother. The analysis on a large panel of genes (n = 138), putatively associated with sudden cardiac death, revealed, in the proband, a third variant in a different gene (DES) that encodes the protein desmin. Our results indicate that: i) NGS revealed a mutational event in a gene not conventionally screened as a first-line test in the presence of clinical suspicion of the arrhythmic disease; ii) a plurality of variants in different genes in the same subject (the proband) may increase the risk of heart disease; iii) in silico analysis with various methodological software and bioinformatic prediction tools indicates that the cumulative effects of the three variants in the same subject constitute an additional risk factor. This case report indicates that more pathogenic variants or likely pathogenic variants can contribute to the clinical phenotype of an individual, thereby contributing to the diagnosis and prognosis of inherited heart diseases.