bluuebunny/crossref_metadata_2025 huggingface dataset:
Gel Formation at the Front of Expanding Calcium Bentonites
Authors: Daniels Katherine A. , Harrington Jon F. , Milodowski Antoni E. , Kemp Simon J. , Mounteney Ian , Sellin Patrik
Published: February 2021

The removal of potentially harmful radioactive waste from the anthroposphere will require disposal in geological repositories, the designs of which often favour the inclusion of a clay backfill or engineered barrier around the waste. Bentonite is often proposed as this engineered barrier and understanding its long-term performance and behaviour is vital in establishing the safety case for its usage. There are many different compositions of bentonite that exist and much research has focussed on the properties and behaviour of both sodium (Na) and calcium (Ca) bentonites. This study focusses on the results of a swelling test on Bulgarian Ca bentonite that showed an unusual gel formation at the expanding front, unobserved in previous tests of this type using the sodium bentonite MX80. The Bulgarian Ca bentonite was able to swell to completely fill an internal void space over the duration of the test, with a thin gel layer present on one end of the sample. The properties of the gel, along with the rest of the bulk sample, have been investigated using ESEM, EXDA and XRD analyses and the formation mechanism has been attributed to the migration of nanoparticulate smectite through a more silica-rich matrix of the bentonite substrate. The migration of smectite clay out of the bulk of the sample has important implications for bentonite erosion where this engineered barrier interacts with flowing groundwater in repository host rocks.
On the Application of the Particle Swarm Optimization to the Inverse Determination of Material Model Parameters for Cutting Simulations
Authors: Hardt Marvin , Jayaramaiah Deepak , Bergs Thomas
Published: February 2021

The manufacturing industry is confronted with increasing demands for digitalization. To realize a digital twin of the cutting process, an increase of the model reliability of the virtual representation becomes necessary. Thereby, different models are required to represent the experimental behavior of the workpiece material or frictional interactions. One of the most utilized material models is the Johnson–Cook material model. The material model parameters are determined either by conventional or by non-conventional material tests, or inversely from the cutting process. However, the inverse parameter determination, where the model parameters are iteratively modified until a sufficient agreement between experimental and numerical results is reached, is not robust and requires a high number of iterations. In this paper, an approach for the inverse determination of material model parameters based on the Particle Swarm Optimization (PSO) is presented. The approach was investigated by the inverse re-identification of an initial parameter set. The conducted investigations showed that a material model parameter set can be determined within a small number of iterations. Thereby, the determined material model parameters resulted in deviations of approximately 1% in comparison to their target values. It was shown that the PSO is suitable for the inverse material parameter determination from cutting simulations.
Metal-based Heterogeneous Catalysts for One-Pot Synthesis of Secondary Anilines from Nitroarenes and Aldehydes
Authors: Romanazzi Giuseppe , Petrelli Valentina , Fiore Ambra Maria , Mastrorilli Piero , Dell’Anna Maria Michela
Published: February 2021

Recently, N-substituted anilines have been the object of increasing research interest in the field of organic chemistry due to their role as key intermediates for the synthesis of important compounds such as polymers, dyes, drugs, agrochemicals and pharmaceutical products. Among the various methods reported in literature for the formation of C–N bonds to access secondary anilines, the one-pot reductive amination of aldehydes with nitroarenes is the most interesting procedure, because it allows to obtain diverse N-substituted aryl amines by simple reduction of nitro compounds followed by condensation with aldehydes and subsequent reduction of the imine intermediates. These kinds of tandem reactions are generally catalyzed by transition metal-based catalysts, mainly potentially reusable metal nanoparticles. The rapid growth in the last years in the field of metal-based heterogeneous catalysts for the one-pot reductive amination of aldehydes with nitroarenes demands for a review on the state of the art with a special emphasis on the different kinds of metals used as catalysts and their recyclability features.
PSC-db: A Structured and Searchable 3D-Database for Plant Secondary Compounds
Authors: Valdés-Jiménez Alejandro , Peña-Varas Carlos , Borrego-Muñoz Paola , Arrue Lily , Alegría-Arcos Melissa , Nour-Eldin Hussam , Dreyer Ingo , Nuñez-Vivanco Gabriel , Ramírez David
Published: February 2021

Plants synthesize a large number of natural products, many of which are bioactive and have practical values as well as commercial potential. To explore this vast structural diversity, we present PSC-db, a unique plant metabolite database aimed to categorize the diverse phytochemical space by providing 3D-structural information along with physicochemical and pharmaceutical properties of the most relevant natural products. PSC-db may be utilized, for example, in qualitative estimation of biological activities (Quantitative Structure-Activity Relationship, QSAR) or massive docking campaigns to identify new bioactive compounds, as well as potential binding sites in target proteins. PSC-db has been implemented using the open-source PostgreSQL database platform where all compounds with their complementary and calculated information (classification, redundant names, unique IDs, physicochemical properties, etc.) were hierarchically organized. The source organism for each compound, as well as its biological activities against protein targets, cell lines and different organism were also included. PSC-db is freely available for public use and is hosted at the Universidad de Talca.
Advances and Perspectives in the Management of Varicella-Zoster Virus Infections
Authors: Andrei Graciela , Snoeck Robert
Published: February 2021

Varicella-zoster virus (VZV), a common and ubiquitous human-restricted pathogen, causes a primary infection (varicella or chickenpox) followed by establishment of latency in sensory ganglia. The virus can reactivate, causing herpes zoster (HZ, shingles) and leading to significant morbidity but rarely mortality, although in immunocompromised hosts, VZV can cause severe disseminated and occasionally fatal disease. We discuss VZV diseases and the decrease in their incidence due to the introduction of live-attenuated vaccines to prevent varicella or HZ. We also focus on acyclovir, valacyclovir, and famciclovir (FDA approved drugs to treat VZV infections), brivudine (used in some European countries) and amenamevir (a helicase-primase inhibitor, approved in Japan) that augur the beginning of a new era of anti-VZV therapy. Valnivudine hydrochloride (FV-100) and valomaciclovir stearate (in advanced stage of development) and several new molecules potentially good as anti-VZV candidates described during the last year are examined. We reflect on the role of antiviral agents in the treatment of VZV-associated diseases, as a large percentage of the at-risk population is not immunized, and on the limitations of currently FDA-approved anti-VZV drugs. Their low efficacy in controlling HZ pain and post-herpetic neuralgia development, and the need of multiple dosing regimens requiring daily dose adaptation for patients with renal failure urges the development of novel anti-VZV drugs.
Establishing an Analogue Based In Silico Pipeline in the Pursuit of Novel Inhibitory Scaffolds against the SARS Coronavirus 2 Papain-Like Protease
Authors: Hajbabaie Roxanna , Harper Matthew T. , Rahman Taufiq
Published: February 2021

The ongoing coronavirus pandemic has been a burden on the worldwide population, with mass fatalities and devastating socioeconomic consequences. It has particularly drawn attention to the lack of approved small-molecule drugs to inhibit SARS coronaviruses. Importantly, lessons learned from the SARS outbreak of 2002–2004, caused by severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1), can be applied to current drug discovery ventures. SARS-CoV-1 and SARS-CoV-2 both possess two cysteine proteases, the main protease (Mpro) and the papain-like protease (PLpro), which play a significant role in facilitating viral replication, and are important drug targets. The non-covalent inhibitor, GRL-0617, which was found to inhibit replication of SARS-CoV-1, and more recently SARS-CoV-2, is the only PLpro inhibitor co-crystallised with the recently solved SARS-CoV-2 PLpro crystal structure. Therefore, the GRL-0617 structural template and pharmacophore features are instrumental in the design and development of more potent PLpro inhibitors. In this work, we conducted scaffold hopping using GRL-0617 as a reference to screen over 339,000 ligands in the chemical space using the ChemDiv, MayBridge, and Enamine screening libraries. Twenty-four distinct scaffolds with structural and electrostatic similarity to GRL-0617 were obtained. These proceeded to molecular docking against PLpro using the AutoDock tools. Of two compounds that showed the most favourable predicted binding affinities to the target site, as well as comparable protein-ligand interactions to GRL-0617, one was chosen for further analogue-based work. Twenty-seven analogues of this compound were further docked against the PLpro, which resulted in two additional hits with promising docking profiles. Our in silico pipeline consisted of an integrative four-step approach: (1) ligand-based virtual screening (scaffold-hopping), (2) molecular docking, (3) an analogue search, and, (4) evaluation of scaffold drug-likeness, to identify promising scaffolds and eliminate those with undesirable properties. Overall, we present four novel, and lipophilic, scaffolds obtained from an exhaustive search of diverse and uncharted regions of chemical space, which may be further explored in vitro through structure-activity relationship (SAR) studies in the search for more potent inhibitors. Furthermore, these scaffolds were predicted to have fewer off-target interactions than GRL-0617. Lastly, to our knowledge, this work contains the largest ligand-based virtual screen performed against GRL-0617.
Inorganic Nanoparticle-Loaded Exosomes for Biomedical Applications
Authors: Barjesteh Taraneh , Mansur Shomit , Bao Yuping
Published: February 2021

Exosomes are intrinsic cell-derived membrane vesicles in the size range of 40–100 nm, serving as great biomimetic nanocarriers for biomedical applications. These nanocarriers are known to bypass biological barriers, such as the blood–brain barrier, with great potential in treating brain diseases. Exosomes are also shown to be closely associated with cancer metastasis, making them great candidates for tumor targeting. However, the clinical translation of exosomes are facing certain critical challenges, such as reproducible production and in vivo tracking of their localization, distribution, and ultimate fate. Recently, inorganic nanoparticle-loaded exosomes have been shown great benefits in addressing these issues. In this review article, we will discuss the preparation methods of inorganic nanoparticle-loaded exosomes, and their applications in bioimaging and therapy. In addition, we will briefly discuss their potentials in exosome purification.
Optical Gain in Semiconducting Polymer Nano and Mesoparticles
Authors: Geoghegan Mark , Mróz Marta M. , Botta Chiara , Parrenin Laurie , Brochon Cyril , Cloutet Eric , Pavlopoulou Eleni , Hadziioannou Georges , Virgili Tersilla
Published: February 2021

The presence of excited-states and charge-separated species was identified through UV and visible laser pump and visible/near-infrared probe femtosecond transient absorption spectroscopy in spin coated films of poly[N-9″-heptadecanyl-2,7-carbazole-alt-5,5-(4,7-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) nanoparticles and mesoparticles. Optical gain in the mesoparticle films is observed after excitation at both 400 and 610 nm. In the mesoparticle film, charge generation after UV excitation appears after around 50 ps, but little is observed after visible pump excitation. In the nanoparticle film, as for a uniform film of the pure polymer, charge formation was efficiently induced by UV excitation pump, while excitation of the low energetic absorption states (at 610 nm) induces in the nanoparticle film a large optical gain region reducing the charge formation efficiency. It is proposed that the different intermolecular interactions and molecular order within the nanoparticles and mesoparticles are responsible for their markedly different photophysical behavior. These results therefore demonstrate the possibility of a hitherto unexplored route to stimulated emission in a conjugated polymer that has relatively undemanding film preparation requirements.
Scavenger Receptor A1 Mediates the Uptake of Carboxylated and Pristine Multi-Walled Carbon Nanotubes Coated with Bovine Serum Albumin
Authors: Huynh Mai T. , Mikoryak Carole , Pantano Paul , Draper Rockford
Published: February 2021

Previously, we noted that carboxylated multi-walled carbon nanotubes (cMWNTs) coated with Pluronic® F-108 (PF108) bound to and were accumulated by macrophages, but that pristine multi-walled carbon nanotubes (pMWNTs) coated with PF108 were not (Wang et al., Nanotoxicology2018, 12, 677). Subsequent studies with Chinese hamster ovary (CHO) cells that overexpressed scavenger receptor A1 (SR-A1) and with macrophages derived from mice knocked out for SR-A1 provided evidence that SR-A1 was a receptor of PF108-cMWNTs (Wang et al., Nanomaterials (Basel) 2020, 10, 2417). Herein, we replaced the PF108 coat with bovine serum albumin (BSA) to investigate how a BSA corona affected the interaction of multi-walled carbon nanotubes (MWNTs) with cells. Both BSA-coated cMWNTs and pMWNTs bound to and were accumulated by RAW 264.7 macrophages, although the cells bound two times more BSA-coated cMWNT than pMWNTs. RAW 264.7 cells that were deleted for SR-A1 using CRISPR-Cas9 technology had markedly reduced binding and accumulation of both BSA-coated cMWNTs and pMWNTs, suggesting that SR-A1 was responsible for the uptake of both MWNT types. Moreover, CHO cells that ectopically expressed SR-A1 accumulated both MWNT types, whereas wild-type CHO cells did not. One model to explain these results is that SR-A1 can interact with two structural features of BSA-coated cMWNTs, one inherent to the oxidized nanotubes (such as COOH and other oxidized groups) and the other provided by the BSA corona; whereas SR-A1 only interacts with the BSA corona of BSA-pMWNTs.
The Role of LncRNAs in Translation
Authors: Karakas Didem , Ozpolat Bulent
Published: February 2021

Long non-coding RNAs (lncRNAs), a group of non-protein coding RNAs with lengths of more than 200 nucleotides, exert their effects by binding to DNA, mRNA, microRNA, and proteins and regulate gene expression at the transcriptional, post-transcriptional, translational, and post-translational levels. Depending on cellular location, lncRNAs are involved in a wide range of cellular functions, including chromatin modification, transcriptional activation, transcriptional interference, scaffolding and regulation of translational machinery. This review highlights recent studies on lncRNAs in the regulation of protein translation by modulating the translational factors (i.e, eIF4E, eIF4G, eIF4A, 4E-BP1, eEF5A) and signaling pathways involved in this process as wells as their potential roles as tumor suppressors or tumor promoters.
Consumption of Ultra-Processed Food and Its Association with Sociodemographic Characteristics and Diet Quality in a Representative Sample of French Adults
Authors: Calixto Andrade Giovanna , Julia Chantal , Deschamps Valérie , Srour Bernard , Hercberg Serge , Kesse-Guyot Emmanuelle , Allès Benjamin , Chazelas Eloi , Deschasaux Mélanie , Touvier Mathilde , Augusto Monteiro Carlos , Bertazzi Levy Renata
Published: February 2021

The present study aims to describe ultra-processed food (UPF) consumption in a representative sample of French adults and to evaluate the association between UPF consumption and socioeconomic characteristics and nutritional profile of the diet. This is a cross-sectional study using food consumption data from the Étude Nationale Nutrition Santé (ENNS), conducted with 2642 participants (18–74 years old), between February 2006 and March 2007 in France. Dietary data were collected through three 24-h dietary recalls. All food and beverages were classified according to the NOVA classification. The energy contribution of NOVA food groups to total energy intake was presented by categories of sociodemographic characteristics. Linear and logistic regression models were used to estimate the association between the percentage of UPF in the diet with nutritional indicators. The mean daily energy consumption of the adult French population was 2111 kcal, of which 31.1% came from UPF. This percentage was higher among younger individuals, and in the urban area, and lower among individuals with incomplete high school and individuals who were retired. The consumption of UPF was positively associated with the dietary energy density and the dietary contents of total carbohydrates, free sugar, and total and saturated fat, as well as with inadequate dietary energy density, saturated fat, free sugar, and fiber intakes.
Crosstalk between Gut and Brain in Alzheimer’s Disease: The Role of Gut Microbiota Modulation Strategies
Authors: Shabbir Umair , Arshad Muhammad Sajid , Sameen Aysha , Oh Deog-Hwan
Published: February 2021

The gut microbiota (GM) represents a diverse and dynamic population of microorganisms and about 100 trillion symbiotic microbial cells that dwell in the gastrointestinal tract. Studies suggest that the GM can influence the health of the host, and several factors can modify the GM composition, such as diet, drug intake, lifestyle, and geographical locations. Gut dysbiosis can affect brain immune homeostasis through the microbiota–gut–brain axis and can play a key role in the pathogenesis of neurodegenerative diseases, including dementia and Alzheimer’s disease (AD). The relationship between gut dysbiosis and AD is still elusive, but emerging evidence suggests that it can enhance the secretion of lipopolysaccharides and amyloids that may disturb intestinal permeability and the blood–brain barrier. In addition, it can promote the hallmarks of AD, such as oxidative stress, neuroinflammation, amyloid-beta formation, insulin resistance, and ultimately the causation of neural death. Poor dietary habits and aging, along with inflammatory responses due to dysbiosis, may contribute to the pathogenesis of AD. Thus, GM modulation through diet, probiotics, or fecal microbiota transplantation could represent potential therapeutics in AD. In this review, we discuss the role of GM dysbiosis in AD and potential therapeutic strategies to modulate GM in AD.
Detection of Rhodococcus fascians, the Causative Agent of Lily Fasciation in South Korea
Authors: Park Joon Moh , Koo Jachoon , Kang Se Won , Jo Sung Hee , Park Jeong Mee
Published: February 2021

Rhodococcus fascians is an important pathogen that infects various herbaceous perennials and reduces their economic value. In this study, we examined R. fascians isolates carrying a virulence gene from symptomatic lily plants grown in South Korea. Phylogenetic analysis using the nucleotide sequences of 16S rRNA, vicA, and fasD led to the classification of the isolates into four different strains of R. fascians. Inoculation of Nicotiana benthamiana with these isolates slowed root growth and resulted in symptoms of leafy gall. These findings elucidate the diversification of domestic pathogenic R. fascians and may lead to an accurate causal diagnosis to help reduce economic losses in the bulb market.
Determination by Relaxation Tests of the Mechanical Properties of Soft Polyacrylamide Gels Made for Mechanobiology Studies
Authors: Pérez-Calixto Daniel , Amat-Shapiro Samuel , Zamarrón-Hernández Diego , Vázquez-Victorio Genaro , Puech Pierre-Henri , Hautefeuille Mathieu
Published: February 2021

Following the general aim of recapitulating the native mechanical properties of tissues and organs in vitro, the field of materials science and engineering has benefited from recent progress in developing compliant substrates with physical and chemical properties similar to those of biological materials. In particular, in the field of mechanobiology, soft hydrogels can now reproduce the precise range of stiffnesses of healthy and pathological tissues to study the mechanisms behind cell responses to mechanics. However, it was shown that biological tissues are not only elastic but also relax at different timescales. Cells can, indeed, perceive this dissipation and actually need it because it is a critical signal integrated with other signals to define adhesion, spreading and even more complicated functions. The mechanical characterization of hydrogels used in mechanobiology is, however, commonly limited to the elastic stiffness (Young’s modulus) and this value is known to depend greatly on the measurement conditions that are rarely reported in great detail. Here, we report that a simple relaxation test performed under well-defined conditions can provide all the necessary information for characterizing soft materials mechanically, by fitting the dissipation behavior with a generalized Maxwell model (GMM). The simple method was validated using soft polyacrylamide hydrogels and proved to be very useful to readily unveil precise mechanical properties of gels that cells can sense and offer a set of characteristic values that can be compared with what is typically reported from microindentation tests.
Electrochemical Activity of Lignin Based Composite Membranes
Authors: Baloch Marya , Alberro Mikel , Labidi Jalel
Published: February 2021

Our society’s most pressing challenges, like high CO2 emission and the constant battle against energy poverty, require a clean and easier solution to store and utilize the renewable energy resources. However, recent electrochemical components are expensive and harmful to the environment, which restricts their widespread deployment. This study proposes an easy method to synthesize and fabricate composite membranes with abundantly found biomass lignin polymer to replace conventional costly and toxic electrode materials. Easier manipulation of lignin within the polymeric matrix could provide the improved composite to enhance its electrochemical activity. Our major focus is to activate the quinone moiety via oxidation in the polymeric mixture using a strong ionic acid. The physico-chemical and electrochemical characterizations of two different lignins within varied polymeric mixture compositions have been carried out to confirm that the redox properties of pure unmodified lignin could be achieved via intrinsic mutual sharing of the structural properties and intercross linkage leading to improved integrity and redox activity/conductivity.
Thermal Control Processes by Deterministic and Network-Based Models for Energy Use and Control Accuracy in a Building Space
Authors: Ahn Jonghoon
Published: February 2021

Various control approaches for building thermal controls have been studied to improve the energy use which determines a large part of the spatial thermal quality. This research compares the performance of deterministic models and a network-based model to examine the aspects of both energy consumption and thermal comfort. The single-switch deterministic model immediately responds to indoor thermal conditions, but the network-based model sends better-fit signals derived from learned data reflecting seven different climate conditions. As a result, the network-based model improves the thermal comfort level by about 6.1% to 9.4% and the energy efficiency by about 1.8% to 39.5% as compared to a thermostat and a fuzzy model. In the case of a specific weather condition, it can be confirmed that the process of finding efficient control values based on the network-based learning algorithm is more efficient than the conventional deterministic models.
Modular Feedback Control of Networked Systems by Clustering: A Drinking Water Network Case Study
Authors: Maestre José María , Lopez-Rodriguez Francisco , Muros Francisco Javier , Ocampo-Martinez Carlos
Published: February 2021

This article presents a method based on linear matrix inequalities (LMIs) for designing a modular feedback control law, whose synthesis guarantees the system stability, while switching to different network topologies. Such stability is achieved by means of a common Lyapunov function to all network admissible configurations. Several mechanisms to relieve the computational burden of this methodology in large-scale systems are also presented. To assess its applicability, the modular controller is tested on a real case study, namely the Barcelona drinking water network (DWN), and its performance is compared with that of other control strategies, showing the effectiveness of the proposed approach.
Technoeconomic Assessment of Organic Halide Based Gold Recovery from Waste Electronic and Electrical Equipment
Authors: Wordsworth Jamie , Khan Nadia , Blackburn Jack , Camp Jason , Angelis-Dimakis Athanasios
Published: February 2021

Waste Electronic and Electrical Equipment (WEEE) is one of the fastest growing waste streams worldwide, with significant economic value due to the precious metals contained within. Currently, only a small share of the total globally produced quantity produced is treated effectively and a large amount of valuable non-renewable resources are being wasted. Moreover, the methods currently applied in industry on a large scale are not always environmentally friendly. Thus, an economically viable and environmentally friendly method that would achieve high recovery of certain elements is sought. The objective of this paper is to assess four different organic halides as leaching agents for gold recovery from WEEE. Two of them have been previously tested (namely N-bromosuccinimide, NBS, and N-chlorosuccinimide, NCS) and have shown promising results, whereas the other two are novel and were selected due to their lower toxicity levels (trichloroisocyanuric acid, TCICA, and tribromoisocyanuric acid, TBICA). Both commercially supplied pure gold powder and WEEE dust from a recycling company were used as the gold source. Results show that from a technical standpoint, the NBS is a superior solution with both substrates, reaching 61% and 99% extraction efficiency from WEEE dust and pure gold, respectively. The other three methods recorded lower recovery efficiency (with the highest value reaching 36% for NCS, 53% for TCICA and 29% for TBICA). However, taking into account the price of gold and the expenses of the extraction process, only three of the lixiviants tested (NBS, NCS and TCICA) could be potentially profitable and viable on a larger scale.
Calibration of Satellite Low Radiance by AERONET-OC Products and 6SV Model
Authors: Bassani Cristiana , Sterckx Sindy
Published: February 2021

For water quality monitoring using satellite data, it is often required to optimize the low radiance signal through the application of radiometric gains. This work describes a procedure for the retrieval of radiometric gains to be applied to OLI/L8 and MSI/S2A data over coastal waters. The gains are defined by the ratio of the top of atmosphere (TOA) reflectance simulated using the Second Simulation of a Satellite Signal in the Solar Spectrum—vector (6SV) radiative transfer model, REF, and the TOA reflectance acquired by the sensor, MEAS, over AERONET-OC stations. The REF is simulated considering quasi-synchronous atmospheric and aquatic AERONET-OC products and the image acquisition geometry. Both for OLI/L8 and MSI/S2A the measured TOA reflectance was higher than the modeled signal in almost all bands resulting in radiometric gains less than 1. The use of retrieved gains showed an improvement of reflectance remote sensing, Rrs, when with ACOLITE atmospheric correction software. When the gains are applied an accuracy improvement of the Rrs in the 400–700 nm domain was observed except for the first blue band of both sensors. Furthermore, the developed procedure is quick, user-friendly, and easily transferable to other optical sensors.
Adaptive 3D Imaging for Moving Targets Based on a SIMO InISAR Imaging System in 0.2 THz Band
Authors: Li Hongwei , Li Chao , Wu Shiyou , Zheng Shen , Fang Guangyou
Published: February 2021

Terahertz (THz) imaging technology has received increased attention in recent years and has been widely applied, whereas the three-dimensional (3D) imaging for moving targets remains to be solved. In this paper, an adaptive 3D imaging scheme is proposed based on a single input and multi-output (SIMO) interferometric inverse synthetic aperture radar (InISAR) imaging system to achieve 3D images of moving targets in THz band. With a specially designed SIMO antenna array, the angular information of the targets can be determined using the phase response difference in different receiving channels, which then enables accurate tracking by adaptively adjusting the antenna beam direction. On the basis of stable tracking, the high-resolution imaging can be achieved. A combined motion compensation method is proposed to produce well-focused and coherent inverse synthetic aperture radar (ISAR) images from different channels, based on which the interferometric imaging is performed, thus forming the 3D imaging results. Lastly, proof-of-principle experiments were performed with a 0.2 THz SIMO imaging system, verifying the effectiveness of the proposed scheme. Non-cooperative moving targets were accurately tracked and the 3D images obtained clearly identify the targets. Moreover, the dynamic imaging results of the moving targets were achieved. The promising results demonstrate the superiority of the proposed scheme over the existing THz imaging systems in realizing 3D imaging for moving targets. The proposed scheme shows great potential in detecting and monitoring moving targets with non-cooperative movement, including unmanned military vehicles and space debris.
Application of Sentinel-1 and-2 Images in Measuring the Deformation of Kuh-e-Namak (Dashti) Namakier, Iran
Authors: Zhang Sen , Jiang Qigang , Shi Chao , Xu Xitong , Gong Yundi , Xi Jing , Liu Wenxuan , Liu Bin
Published: February 2021

Kuh-e-Namak (Dashti) namakier is one of the most active salt diapirs along the Zagros fold–thrust belt in Iran. Its surface deformation should be measured to estimate its long-term kinematics. Ten Sentinel-2 optical images acquired between October 2016 and December 2019 were processed by using Co-Registration of Optically Sensed Images and Correlation (COSI-Corr) method. Forty-seven Sentinel-1 ascending Synthetic Aperture Radar (SAR) images acquired between April 2017 and December 2019 were processed by using Small Baseline Subset Synthetic Aperture Radar Interferometry (SBAS-InSAR) method. The deformation of Kuh-e-Namak (Dashti) namakier was measured using both methods. Then, meteorological data were utilized to explore the relationship between the kinematics of the namakier and weather conditions and differences in macrodeformation behavior of various rock salt types. The advantages and disadvantages of COSI-Corr and SBAS-InSAR methods in measuring the deformation of the namakier were compared. The results show that: (1) The flank subsides in the dry season and uplifts in the rainy season, whereas the dome subsides in the rainy season and uplifts in the dry season. Under extreme rainfall conditions, the namakier experiences permanent plastic deformation. (2) The “dirty” rock salt of the namakier is more prone to flow than the “clean” rock salt in terms of macrodeformation behavior. (3) In the exploration of the kinematics of the namakier via the two methods, COSI-Corr is superior to SBAS-InSAR on a spatial scale, but the latter is superior to the former on a time scale.
An In-Depth Assessment of the New BDS-3 B1C and B2a Signals
Authors: Zhang Qinghua , Zhu Yongxing , Chen Zhengsheng
Published: February 2021

An in-depth and comprehensive assessment of new observations from BDS-3 satellites is presented, with the main focus on the Carrier-to-Noise density ratio (C/N0), the quality of code and carrier phase observations for B1C and B2a signal. The signal characteristics of geosynchronous earth orbit (GEO), inclined geosynchronous satellite orbit (IGSO) and medium earth orbit (MEO) satellites of BDS-3 were grouped and compared, respectively. The evaluation results of the new B1C and B2a signals of BDS-3 were compared with the previously B1I/B2I/B3I signals and the interoperable signals of GPS, Galileo and quasi-zenith satellite system (QZSS) were compared simultaneously. As expected, the results clearly show that B1C and B2a have better signal strength and higher accuracy, including code and carrier phase observations. The C/N0 of the B2a signal is about 3 dB higher than other signals. One exception is the code observation accuracy of B3I, which value is less than 0.15 m. The carrier precision of B1C and B2a is better than that of B1I/B2I/B3I. Despite difference-in-difference (DD) observation quantity or zero-base line evaluation is adopted, while B1C is about 0.3 mm higher carrier precision than B2a. The BDS-3 MEO satellite and GPS, Galileo, and QZSS satellites have the same level of signal strength, code and phase observation accuracy at the interoperable frequency, namely 1575.42 MHz and 1176.45 MHz which are very suitable for the co-position application.
Quantifying Forest Fire and Post-Fire Vegetation Recovery in the Daxin’anling Area of Northeastern China Using Landsat Time-Series Data and Machine Learning
Authors: Qiu Jie , Wang Heng , Shen Wenjuan , Zhang Yali , Su Huiyi , Li Mingshi
Published: February 2021

Many post-fire on-site factors, including fire severity, management strategies, topography, and local climate, are concerns for forest managers and recovery ecologists to formulate forest vegetation recovery plans in response to climate change. We used the Vegetation Change Tracker (VCT) algorithm to map forest disturbance in the Daxing’anling area, Northeastern China, from 1987 to 2016. A support vector machine (SVM) classifier and historical fire records were used to separate burned patches from disturbance patches obtained from VCT. Afterward, stepwise multiple linear regression (SMLR), SVM, and random forest (RF) were applied to assess the statistical relationships between vegetation recovery characteristics and various influential factors. The results indicated that the forest disturbance events obtained from VCT had high spatial accuracy, ranging from 70% to 86% for most years. The overall accuracy of the annual fire patches extracted from the proposed VCT-SVM algorithm was over 92%. The modeling accuracy of post-fire vegetation recovery was excellent, and the validation results confirmed that the RF algorithm provided better prediction accuracy than SVM and SMLR. In conclusion, topographic variables (e.g., elevation) and meteorological variables (e.g., the post-fire annual precipitation in the second year, the post-fire average relative humidity in the fifth year, and the post-fire extreme maximum temperature in the third year) jointly affect vegetation recovery in this cold temperate continental monsoon climate region.
Improving the Capability of the SCOPE Model for Simulating Solar-Induced Fluorescence and Gross Primary Production Using Data from OCO-2 and Flux Towers
Authors: Wang Haibo , Xiao Jingfeng
Published: February 2021

Solar-induced chlorophyll fluorescence (SIF) measured from space has shed light on the diagnosis of gross primary production (GPP) and has emerged as a promising way to quantify plant photosynthesis. The SCOPE model can explicitly simulate SIF and GPP, while the uncertainty in key model parameters can lead to significant uncertainty in simulations. Previous work has constrained uncertain parameters in the SCOPE model using coarse-resolution SIF observations from satellites, while few studies have used finer resolution SIF measured from the Orbiting Carbon Observatory-2 (OCO-2) to improve the model. Here, we identified the sensitive parameters to SIF and GPP estimation, and improved the performance of SCOPE in simulating SIF and GPP for temperate forests by constraining the physiological parameters relating to SIF and GPP by combining satellite-based SIF measurements (e.g., OCO-2) with flux tower GPP data. Our study showed that SIF had weak capability in constraining maximum carboxylation capacity (Vcmax), while GPP could constrain this parameter well. The OCO-2 SIF data constrained fluorescence quantum efficiency (fqe) well and improved the performance of SCOPE in SIF simulation. However, the use of the OCO-2 SIF alone cannot significantly improve the GPP simulation. The use of both satellite SIF and flux tower GPP data as constraints improved the performance of the model for simulating SIF and GPP simultaneously. This analysis is useful for improving the capability of the SCOPE model, understanding the relationships between GPP and SIF, and improving the estimation of both SIIF and GPP by incorporating satellite SIF products and flux tower data.
Determining the Optimal Workrate for Cycle Ergometer Verification Phase Testing in Males with Obesity
Authors: Mahoney Jenny M. , Baughman Brett R. , Sheard Ailish C. , Sawyer Brandon J.
Published: February 2021

The aim of the present study was to assess the validity of verification phase (VP) testing and a 3 min all-out test to determine critical power (CP) in males with obesity. Nine young adult males with a body mass index (BMI) ≥ 30 kg·m−2 completed a cycle ergometer ramp-style VO2max test, four randomized VP tests at 80, 90, 100, and 105% of maximum wattage attained during the ramp test, and a 3 min all-out test. There was a significant main effect for VO2max across all five tests (p = 0.049). Individually, 8 of 9 participants attained a higher VO2max (L/min) during a VP test compared to the ramp test. A trend (p = 0.06) was observed for VO2max during the 90% VP test (3.61 ± 0.54 L/min) when compared to the ramp test (3.37 ± 0.39 L/min). A significantly higher VO2max (p = 0.016) was found in the VP tests that occurred below 130% of CP wattage (N = 15, VO2max = 3.76 ± 0.52 L/min) compared to those that were above (N = 21, VO2max = 3.36 ± 0.41 L/min). Our findings suggest submaximal VP tests at 90% may elicit the highest VO2max in males with obesity and there may be merit in using % of CP wattage to determine optimal VP intensity.
Sharing the Agrarian Knowledge with Archaeology: First Evidence of the Dimorphism of Vitis Pollen from the Middle Bronze Age of N Italy (Terramara Santa Rosa di Poviglio)
Authors: Mercuri Anna Maria , Torri Paola , Florenzano Assunta , Clò Eleonora , Mariotti Lippi Marta , Sgarbi Elisabetta , Bignami Cristina
Published: February 2021

The recovery of inaperturate pollen from functionally female flowers in archaeological layers opens the question of a possible pollen-based discrimination between wild and domesticated Vitis vinifera in prehistoric times. Pollen analysis applied to archaeology has not routinely considered the existence of pollen dimorphism in Vitis, a well-known trait in the field of agrarian studies. Therefore, the inaperturate shape of grapevine pollen is ignored by studies on the archaeobotanical history of viticulture. In this paper we investigate pollen morphology of the domesticated and wild subspecies of V. vinifera, and report the first evidence of inaperturate Vitis pollen from an archaeological site. We studied exemplar cases of plants with hermaphroditic flowers, belonging to the subspecies vinifera with fully developed male and female organs, cases of dioecious plants with male or female flowers, belonging to the wild subspecies sylvestris and cases of V. vinifera subsp. vinifera with morphologically hermaphroditic but functionally female flowers. The pollen produced by hermaphroditic and male flowers is usually trizonocolporate; the pollen produced by female flowers is inaperturate. This paper reports on the inaperturate pollen of Vitis found in an archeological site of the Po Plain, Northern Italy. The site dated to the Bronze Age, which is known to have been a critical age for the use of this plant with a transition from wild to domesticated Vitis in central Mediterranean. Can the inaperturate Vitis pollen be a marker of wild Vitis vinifera in prehistoric times? Palynology suggests a possible new investigation strategy on the ancient history of the wild and cultivated grapevine. The pollen dimorphism also implies a different production and dispersal of pollen of the wild and the domesticated subspecies. Grapevine plants are palynologically different from the other Mediterranean “cultural trees”. In fact, Olea, Juglans and Castanea, which are included in the OJC index, have the same pollen morphology and the same pollen dispersal, in wild and domesticated plants. In contrast, the signal of Vitis pollen in past records may be different depending on the hermaphroditic or dioecious subspecies.
The Potentials and Challenges of Achieving Sustainability through Charcoal Producer Associations in Kenya: A Missed Opportunity?
Authors: Kamwilu Esther , Duguma Lalisa A. , Orero Levi
Published: February 2021

The charcoal industry, specifically charcoal production, is tremendously valuable to Kenya for its contribution to economic, social and environmental nexus. Considering the degradation of ecosystems and charcoal production’s critical role, the government established the Forest (charcoal) rules of 2009, assigning commercial charcoal production under Charcoal Producer Associations (CPAs). Identifying numerous bans in the recent past, this paper sets out to understand CPAs’ potentials and challenges in attaining sustainability within the sector. Using focus group discussions with CPA members from Tana River and Kitui counties, the paper outlines analysed data within the functionality, governance and policy implications parameters of operation. The findings show high economic value for the members and an in-depth environmental significance to the communities within which these CPAs exist. Thus, we propose a schematic to enhance charcoal production processes to achieve sustainable ecosystems and livelihoods. There is high potential within the CPAs for the sector’s sustainability through monitoring platforms, restoration plans, adopting sustainable practices, knowledge dissemination and societal advancement. To advance this untapped potential of these associations, we recommend building their technical, business and governance skills, exploring various restoration schemes, financial and regulatory support in implementation, and policy support.
Genomic Characterization of the Three Balkan Livestock Guardian Dogs
Authors: Janeš Mateja , Zorc Minja , Ferenčaković Maja , Curik Ino , Dovč Peter , Cubric-Curik Vlatka
Published: February 2021

Balkan Livestock Guardian Dogs (LGD) were bred to help protect sheep flocks in sparsely populated, remote mountainous areas in the Balkans. The aim of this study was genomic characterization (107,403 autosomal SNPs) of the three LGD breeds from the Balkans (Karst Shepherd, Sharplanina Dog, and Tornjak). Our analyses were performed on 44 dogs representing three Balkan LGD breeds, as well as on 79 publicly available genotypes representing eight other LGD breeds, 70 individuals representing seven popular breeds, and 18 gray wolves. The results of multivariate, phylogenetic, clustering (STRUCTURE), and FST differentiation analyses showed that the three Balkan LGD breeds are genetically distinct populations. While the Sharplanina Dog and Tornjak are closely related to other LGD breeds, the Karst Shepherd is a slightly genetically distinct population with estimated influence from German Shepard (Treemix analysis). Estimated genomic diversity was high with low inbreeding in Sharplanina Dog (Ho = 0.315, He = 0.315, and FROH>2Mb = 0.020) and Tornjak (Ho = 0.301, He = 0.301, and FROH>2Mb = 0.033) breeds. Low diversity and high inbreeding were estimated in Karst Shepherds (Ho = 0.241, He = 0.222, and FROH>2Mb = 0.087), indicating the need for proper diversity management. The obtained results will help in the conservation management of Balkan LGD dogs as an essential part of the specific grazing biocultural system and its sustainable maintenance.
Spatial Conditions Supporting Sustainable Development of Enterprises on Local Level
Authors: Ptak-Chmielewska Aneta , Chłoń-Domińczak Agnieszka
Published: February 2021

Micro, small and medium enterprises (MSMEs) represent more than 99% of enterprises in Europe. Therefore, knowledge about this sector, also in the spatial context is important to understand the patterns of economic and social development. The main goal of this article is an analysis of spatial conditions and the situation of MSMEs on a local level using combined sources of information. This includes data collected in the Social Insurance Institution and Tax registers in Poland, which provides information on the employment, wages, revenues and taxes paid by the MSMEs on a local level as well as contextual statistical information. The data is used for a diagnosis of spatial circumstances and discussion of conditions influencing the status of the MSMEs sector in a selected region (voivodeship) in Poland. Taxonomy methods including factor analysis and clustering methods based on k-means and SOM Kohonen were used for selecting significant information and grouping of the local units according to the situation of the MSMEs. There are eight factors revealed in principal component analysis and five clusters of local units distinguished using these factors. These include two clusters with a high share of rural local units and two clusters with a high share of rural-urban and urban local units. Additionally, there was an outstanding cluster with only two dominant urban local units. Factors show differences between clusters in the situation of MSMEs sector and infrastructure. Different spatial conditions in different regions influence the situation of MSMEs.
Acceptance and Potential of Renewable Energy Sources Based on Biomass in Rural Areas of Hungary
Authors: Titov Alexander , Kövér György , Tóth Katalin , Gelencsér Géza , Kovács Bernadett Horváthné
Published: February 2021

The main focus of the paper is the investigation of the social potential of local renewable energy utilization in a rural peripheral region in Hungary. Public acceptance of biomass-based renewable energy sources can be crucial for rural communities in realization of their sustainable development strategy. The research area was Koppany Valley Natur Park 2000, a microregion of 10 settlements located in the South Transdanubian region. This microregion is characterized by poor and depressive socioeconomic and demographical conditions, despite its significant natural resources. The microregion’s complex development strategy includes the utilization of local resources of renewable energy. Local population survey (n = 310) was conducted (in May 2018) on local biomass potential, knowledge, and attitudes of the local stakeholders in the microregion. Multinomial logistic regression model estimates the acceptance of population, explanatory variables are categorical demographical (personal) factors and specific factors (based on answers of respondents). Trust in local authorities, knowledge on biomass in general and on specific technologies, as well as the education level of rural inhabitants are significant factors in supporting biomass plant establishment. Further, the group and characteristics of acceptance groups that the local development strategy may consider were defined.