bluuebunny/crossref_metadata_2025 huggingface dataset:
Altitudinal Heterogeneity of UV Adaptation in Phytophthorainfestans Is Associated with the Spatial Distribution of a DNA Repair Gene
Authors: Wang Yan-Ping , Waheed Abdul , Liu Shi-Ting , Li Wen-Yang , Nkurikiyimfura Oswald , Lurwanu Yahuza , Wang Zonghua , Grenville-Briggs Laura J. , Yang Lina , Zheng Luping , Zhan Jiasui
Published: March 2021

Climate change is considered a major threat to society and nature. UV irradiation is the most important environmental genotoxic agent. Thus, how elevated UV irradiation may influence human health and ecosystems has generated wide concern in the scientific community, as well as with policy makers and the public in general. In this study, we investigated patterns and mechanisms of UV adaptation in natural ecosystems by studying a gene-specific variation in the potato late blight pathogen, Phytophthora infestans. We compared the sequence characteristics of radiation sensitive 23 (RAD23), a gene involved in the nucleotide excision repair (NER) pathway and UV tolerance, in P. infestans isolates sampled from various altitudes. We found that lower genetic variation in the RAD23 gene was caused by natural selection. The hypothesis that UV irradiation drives this selection was supported by strong correlations between the genomic characteristics and altitudinal origin (historic UV irradiation) of the RAD23 sequences with UV tolerance of the P. infestans isolates. These results indicate that the RAD23 gene plays an important role in the adaptation of P. infestans to UV stress. We also found that different climatic factors could work synergistically to determine the evolutionary adaptation of species, making the influence of climate change on ecological functions and resilience more difficult to predict. Future attention should aim at understanding the collective impact generated by simultaneous change in several climate factors on species adaptation and ecological sustainability, using state of the art technologies such as experimental evolution, genome-wide scanning, and proteomics.
Economic Policy Uncertainty and Stock Return Momentum
Authors: Goel Garima , Dash Saumya Ranjan , Mata Mário Nuno , Caleiro António Bento , Xavier Rita João , Filipe José António
Published: March 2021

This paper investigates the relationship between economic policy uncertainty (EPU), an index capturing newspaper coverage of policy-related issues, and momentum profits. Momentum remains an unexplained anomaly. Our findings reveal a statistically negative association between EPU and hedge momentum portfolios. The short side portfolio dominates this effect as compared to the long side. EPU is statistically significant after controlling for macroeconomic variables. Furthermore, the paper conducts a battery of time series analysis, which highlights that EPU has a causal relationship with the hedge portfolio in the short run. On the other hand, the hedge portfolio has a long-term relationship with EPU, not the other way around.
Attitudes towards Turkish and Turks in Austria: From Guestworkers to “Quasi-Foreigners” in a Changing Social Landscape
Authors: Woschitz Johannes
Published: March 2021

In Austria, Turkish immigrants have long suffered from the stigma of being the uneducated and unintegrated guestworker, often portrayed as marginalised and as living in parallel societies. However, second-generation Turks who were born and/or raised in Austria have challenged this stigma profoundly. This paper argues that this has led to a re-indexicalisation of Turkish in Austria. Evidence for this is drawn from two matched-guise studies (n = 226) that aimed to unearth the covert language attitudes of Austrian participants towards Turkish. The data presented shows that many Austrian participants still conceive of the Turkish guises in overall xenophobic terms. They were depicted as more aggressive, less educated, less integrated, more joyous of life and more family-oriented when compared to the German guises. There was, however, an age-effect indicative of changing attitudes among participants born after 1998, for whom this stereotype seems to be losing its influence.
Synthetic Emotions for Empathic Building
Authors: Salmeron Jose L. , Ruiz-Celma Antonio
Published: March 2021

Empathic buildings are intelligent ones that aim to measure and execute the best user experience. A smoother and intuitive environment leads to a better mood. The system gathers data from sensors that measure things like air quality, occupancy, noise and analyse it for the better experience of the users. This research proposes an artificial intelligence-based approach to detect synthetic emotions based on Thayer’s emotional model and Fuzzy Cognitive Maps. This emotional model is based on a biopsychological approach to the analysis of the humans’ emotional state. In this research, Fuzzy Grey Cognitive Maps are used, which are an extension of the fuzzy cognitive maps using the grey systems theory to model uncertainty. Fuzzy Cognitive Grey Maps (FGCMs) have become a very valuable theory for modeling high-uncertainty systems when small and incomplete discrete data sets are available. This research includes experiments with a couple of synthetic case studies for testing this proposal. This proposal provides an innovative way for simulating synthetic emotions and designing an empathic building.
Convolutional Neural Network-Based Cryptography Ransomware Detection for Low-End Embedded Processors
Authors: Kim Hyunji , Park Jaehoon , Kwon Hyeokdong , Jang Kyoungbae , Seo Hwajeong
Published: March 2021

A crypto-ransomware has the process to encrypt victim’s files. Afterward, the crypto-ransomware requests a ransom for the password of encrypted files to victims. In this paper, we present a novel approach to prevent crypto-ransomware by detecting block cipher algorithms for Internet of Things (IoT) platforms. We extract the sequence and frequency characteristics from the opcode of binary files for the 8-bit Alf and Vegard’s RISC (AVR) processor microcontroller. In other words, the late fusion method is used to extract two features from one source data, learn through each network, and integrate them. We classify the crypto-ransomware virus or harmless software through the proposed method. The general software from AVR packages and block cipher implementations written in C language from lightweight block cipher library (i.e., Fair Evaluation of Lightweight Cryptographic Systems (FELICS)) are trained through the deep learning network and evaluated. The general software and block cipher algorithms are successfully classified by training functions in binary files. Furthermore, we detect binary codes that encrypt a file using block ciphers. The detection rate is evaluated in terms of F-measure, which is the harmonic mean of precision and recall. The proposed method not only achieved 97% detection success rate for crypto-ransomware but also achieved 80% success rate in classification for each lightweight cryptographic algorithm and benign firmware. In addition, the success rate in classification for Substitution-Permutation-Network (SPN) structure, Addition-Rotation-eXclusive-or structures (ARX) structure, and benign firmware is 95%.
A Unique Anti-Cancer 3-Styrylchromone Suppresses Inflammatory Response via HMGB1-RAGE Signaling
Authors: Abe Hideaki , Okazawa Miwa , Oyama Takahiro , Yamazaki Hiroaki , Yoshimori Atsushi , Kamiya Takanori , Tsukimoto Mitsutoshi , Takao Koichi , Sugita Yoshiaki , Sakagami Hiroshi , Abe Takehiko , Tanuma Sei-ichi
Published: March 2021

Background: High mobility group box 1 (HMGB1)-receptor for advanced glycation endo-products (RAGE) axis serves as a key player in linking inflammation and carcinogenesis. Recently, papaverine was revealed to suppress the HMGB1-RAGE inflammatory signaling pathway and cancer cell proliferation. Therefore, a dual suppressor targeting this axis is expected to become a new type of therapeutic agent to treat cancer. Methods: Papaverine 3D pharmacophore mimetic compounds were selected by the LigandScout software from our in-house, anti-cancer chemical library and assessed for their anti-inflammatory activities by a HMGB1-RAGE-mediated interleukin-6 production assay using macrophage-like RAW264.7 cells. Molecular-biological analyses, such as Western blotting, were performed to clarify the mechanism of action. Results: A unique 6-methoxy-3-hydroxy-styrylchromone was found to possess potent anti-inflammatory and anti-cancer activities via the suppression of the HMGB1-RAGE-extracellular signal-regulated kinase 1/2 signaling pathway. Furthermore, the 3D pharmacophore-activity relationship analyses revealed that the hydroxyl group at the C4′ position of the benzene ring in a 3-styryl moiety was significant in its dual suppressive effects. Conclusions: These findings indicated that this compound may provide a valuable scaffold for the development of a new type of anti-cancer drug possessing anti-inflammatory activity and as a tool for understanding the link between inflammation and carcinogenesis.
Social Determinants of Health Associated with the Use of Screenings for Hypertension, Hypercholesterolemia, and Hyperglycemia among American Adults
Authors: Nguyen Tran , Barefield Amanda , Nguyen Gia-Thien
Published: March 2021

National and international health guidelines have recommended measurements of blood pressure, blood cholesterol, and blood glucose as the first step in detecting hypertension, hypercholesterolemia, and hyperglycemia, respectively. These chronic conditions are modifiable risk factors for chronic diseases such as obesity, diabetes, and cardiovascular disease. Social determinants of health (SDoHs) have contributed to persistent chronic condition disparities in the United States. This study identified SDoHs associated with the use of screening services for hypertension, hypercholesterolemia, and hyperglycemia by analyzing data from the 2019 United States National Health Interview Survey. Examined SDoHs consisted of demographic characteristics, socioeconomic status, and health care utilization. Age, gender, education, annual income, health coverage, and usual care source were positively associated with the odds of receiving secondary preventive services. There was a marginal significance among race/ethnicity and employment status in association with the odds of receiving secondary preventive services. This study’s findings inform health educators and providers, public health professionals, and policymakers to fund, plan, and coordinate services and interventions accordingly to improve the population’s quality of life and lengthen lifespan by promptly diagnosing and treating these diseases.
Actinotignum schaalii: Relation to Concomitants and Connection to Patients’ Conditions in Polymicrobial Biofilms of Urinary Tract Catheters and Urines
Authors: Kotásková Iva , Syrovátka Vít , Obručová Hana , Vídeňská Petra , Zwinsová Barbora , Holá Veronika , Blaštíková Eva , Růžička Filip , Freiberger Tomáš
Published: March 2021

Actinotignum schaalii is an emerging, opportunistic pathogen and its connection to non-infectious diseases and conditions, such as prostate or bladder cancer, or chronic inflammation has been proposed. Here, we analyzed 297 urine, ureteral and urinary catheter samples from 128 patients by Polymerase Chain Reaction followed by Denaturing Gradient Gel Electrophoresis and Sequencing (PCR-DGGE-S), and culture, and 29 of these samples also by 16S rRNA Illumina sequencing, to establish A. schaalii’s prevalence in urinary tract-related samples, its relation to other bacteria, and its potential association with patients’ conditions and samples’ characteristics. A. schaalii-positive samples were significantly more diverse than A. schaalii negative and between-group diversity was higher than intra-group. Propionimicrobium lymphophilum, Fusobacterium nucleatum, Veillonella sp., Morganella sp., and Aerococcus sp. were significantly more often present in A. schaalii-positive samples; thus, we suggest these species are A. schaalii’s concomitants, while Enterobacter and Staphylococcaceae were more often identified in A. schaalii-negative samples; therefore, we propose A. schaalii and these species are mutually exclusive. Additionally, a significantly higher A. schaalii prevalence in patients with ureter stricture associated hydronephrosis (p = 0.020) was noted. We suggest that A. schaalii could be an early polybacterial biofilm colonizer, together with concomitant species, known for pro-inflammatory features.
Antibiotics as a Stressing Factor Triggering the Harboring of Helicobacter pylori J99 within Candida albicans ATCC10231
Authors: Sánchez-Alonzo Kimberly , Belmar Libnny , Parra-Sepúlveda Cristian , Bernasconi Humberto , Campos Víctor L. , Smith Carlos T. , Sáez Katia , García-Cancino Apolinaria
Published: March 2021

First-line treatment for Helicobacter pylori includes amoxicillin and clarithromycin or metronidazole plus a proton pump inhibitor. Treatment failure is associated with antibiotic resistance and possibly also with internalization of H. pylori into eukaryotic cells, such as yeasts. Factors triggering the entry of H. pylori into yeast are poorly understood. Therefore, the aim of this study was to evaluate whether clarithromycin or amoxicillin trigger the entry of H. pylori into C. albicans cells. Methods: H. pylori J99 and C. albicans ATCC 10231 were co-cultured in the presence of subinhibitory concentrations of amoxicillin and clarithromycin as stressors. Bacterial-bearing yeasts were observed by fresh examination. The viability of bacteria within yeasts was evaluated, confirming the entry of bacteria into Candida, amplifying, by PCR, the H. pylori16S rRNA gene in total yeast DNA. Results: Amoxicillin significantly increased the entry of H. pylori into C. albicans compared to the control. Conclusion: the internalization of H. pylori into C. albicans in the presence of antibiotics is dependent on the type of antibiotic used, and it suggests that a therapy including amoxicillin may stimulate the entry of the bacterium into Candida, thus negatively affecting the success of the treatment.
Evaluation of a Multidisciplinary Bachelor Course on Pain with Autonomy-Supportive Teaching Strategies through the Lens of Self-Determination Theory
Authors: van Houwelingen Adriana H. , Kusurkar Rashmi A. , Engels Ferdi
Published: March 2021

To stimulate learners’ autonomy, autonomy-supportive teaching strategies were included in the design of a multidisciplinary elective course on pain. During this course, students explored pain from different disciplinary angles, i.e., from biomedical, psychological, arts, philosophical, and anthropological perspectives. In the course, autonomy was stimulated by giving students freedom of choice, especially in their final assignments. The aim of this study was to explore students’ freedom of choice and students’ perceptions of the multidisciplinary course on pain, particularly students’ perception of autonomy in the light of self-determination theory (SDT). To address the aim of this study, a mixed methods approach was used. Directed content analysis was conducted on a reflective part of the final individual assignment and was used to find categories fitting within SDT and also outside it. In addition to this, the diversity of topics as well as different disciplines present in the final individual assignments was explored to demonstrate students’ freedom of choice. This study shows that the course setup supported students’ autonomy and relatedness and stimulated students’ interest in and relevance to pain. Moreover, it stimulated students’ freedom of choice and stimulated curiosity towards disciplines such as arts and philosophy. Therefore, it can be concluded that we successfully developed a multidisciplinary course on pain in which students are exposed to different autonomy-supportive teaching strategies based on the SDT framework.
Transverse Asymmetry of the Index Modulation Profile in Few-Mode Fiber Bragg Grating
Authors: Guan Peihong , Tang Min , Cao Min , Mi Yuean , Liu Mei , Ren Wenhua , Ren Guobin
Published: March 2021

The transverse asymmetry of the index modulation profile in the asymmetric few-mode fiber Bragg grating (FM-FBG) was investigated. The transverse asymmetry of the index modulation profile will lead to mode conversion between modes with the different azimuthal orders, and this asymmetry is characterized by the attenuation coefficient α. We evaluated that the value of attenuation coefficient α was 0.2 μm−1, and grating amplitude χ was 2.8 × 10−4 for FM-FBG inscribed by UV single-side illumination. We found that the optimized value of α was 0.16 μm−1, at which the maximum mode conversion efficiency of LP01–LP11 can be achieved. The results of this paper provide great potential application in few-mode fiber (FMF) devices and mode division multiplexing (MDM) optical communication.
A Hidden Anomaly in the Binary Mixture Natural Convection Subject to Flux Boundary Conditions
Authors: Vadasz Peter
Published: March 2021

The problem of natural convection in a binary mixture subject to realistic boundary conditions of imposed zero mass flux on the solid walls shows solutions that might lead to unrealistic negative values of the mass fraction (or solute concentration). This anomaly is being investigated in this paper, and a possible way of addressing it is suggested via a mass-fraction-dependent thermodiffusion coefficient that can have negative values in regions of low mass fractions.
Differences in the Inhibitory Specificity Distinguish the Efficacy of Plant Protease Inhibitors on Mouse Fibrosarcoma
Authors: Yoo Im Sonia , Ramalho Bonturi Camila , Miti Nakahata Adriana , Ryuichi Nakaie Clóvis , Pott Arnildo , Pott Vali Joana , Vilela Oliva Maria Luiza
Published: March 2021

Metastasis, the primary cause of death from malignant tumors, is facilitated by multiple protease-mediated processes. Thus, effort has been invested in the development of protease inhibitors to prevent metastasis. Here, we investigated the effects of protease inhibitors including the recombinant inhibitors rBbKI (serine protease inhibitor) and rBbCI (serine and cysteine inhibitor) derived from native inhibitors identified in Bauhinia bauhinioides seeds, and EcTI (serine and metalloprotease inhibitor) isolated from the seeds of Enterolobium contortisiliquum on the mouse fibrosarcoma model (lineage L929). rBbKI inhibited 80% of cell viability of L929 cells after 48 h, while EcTI showed similar efficacy after 72 h. Both inhibitors acted in a dose and time-dependent manner. Conversely, rBbCI did not significantly affect the viability of L929 cells. Confocal microscopy revealed the binding of rBbKI and EcTI to the L929 cell surface. rBbKI inhibited approximately 63% of L929 adhesion to fibronectin, in contrast with EcTI and rBbCI, which did not significantly interfere with adhesion. None of the inhibitors interfered with the L929 cell cycle phases. The synthetic peptide RPGLPVRFESPL-NH2, based on the BbKI reactive site, inhibited 45% of the cellular viability of L929, becoming a promising protease inhibitor due to its ease of synthesis.
A Review of Bio-Oil Production through Microwave-Assisted Pyrolysis
Authors: Giorcelli Mauro , Das Oisik , Sas Gabriel , Försth Michael , Bartoli Mattia
Published: March 2021

The issue of sustainability is a growing concern and has led to many environmentally friendly chemical productions through a great intensification of the use of biomass conversion processes. Thermal conversion of biomass is one of the most attractive tools currently used, and pyrolytic treatments represent the most flexible approach to biomass conversion. In this scenario, microwave-assisted pyrolysis could be a solid choice for the production of multi-chemical mixtures known as bio-oils. Bio-oils could represent a promising new source of high-value species ranging from bioactive chemicals to green solvents. In this review, we have summarized the most recent developments regarding bio-oil production through microwave-induced pyrolytic degradation of biomasses.
State-of-Art Review of NO Reduction Technologies by CO, CH4 and H2
Authors: Song Jialin , Wang Ziliang , Cheng Xingxing , Wang Xiuping
Published: March 2021

Removal of nitrogen oxides during coal combustion is a subject of great concerns. The present study reviews the state-of-art catalysts for NO reduction by CO, CH4, and H2. In terms of NO reduction by CO and CH4, it focuses on the preparation methodologies and catalytic properties of noble metal catalysts and non-noble metal catalysts. In the technology of NO removal by H2, the NO removal performance of the noble metal catalyst is mainly discussed from the traditional carrier and the new carrier, such as Al2O3, ZSM-5, OMS-2, MOFs, perovskite oxide, etc. By adopting new preparation methodologies and introducing the secondary metal component, the catalysts supported by a traditional carrier could achieve a much higher activity. New carrier for catalyst design seems a promising aspect for improving the catalyst performance, i.e., catalytic activity and stability, in future. Moreover, mechanisms of catalytic NO reduction by these three agents are discussed in-depth. Through the critical review, it is found that the adsorption of NOx and the decomposition of NO are key steps in NO removal by CO, and the activation of the C-H bond in CH4 and H-H bonds in H2 serves as a rate determining step of the reaction of NO removal by CH4 and H2, respectively.
CFD Modelling of a Hydrogen/Air PEM Fuel Cell with a Serpentine Gas Distributor
Authors: d’Adamo Alessandro , Riccardi Matteo , Borghi Massimo , Fontanesi Stefano
Published: March 2021

Hydrogen-fueled fuel cells are considered one of the key strategies to tackle the achievement of fully-sustainable mobility. The transportation sector is paying significant attention to the development and industrialization of proton exchange membrane fuel cells (PEMFC) to be introduced alongside batteries, reaching the goal of complete de-carbonization. In this paper a multi-phase, multi-component, and non-isothermal 3D-CFD model is presented to simulate the fluid, heat, and charge transport processes developing inside a hydrogen/air PEMFC with a serpentine-type gas distributor. Model results are compared against experimental data in terms of polarization and power density curves, including an improved formulation of exchange current density at the cathode catalyst layer, improving the simulation results’ accuracy in the activation-dominated region. Then, 3D-CFD fields of reactants’ delivery to the active electrochemical surface, reaction rates, temperature distributions, and liquid water formation are analyzed, and critical aspects of the current design are commented, i.e., the inhomogeneous use of the active surface for reactions, limiting the produced current and inducing gradients in thermal and reaction rate distribution. The study shows how a complete multi-dimensional framework for physical and chemical processes of PEMFC can be used to understand limiting processes and to guide future development.
Markers for the Comparison of the Performances of Anoxic Biotrickling Filters in Biogas Desulphurisation: A Critical Review
Authors: Valdebenito-Rolack Emky , Díaz Rosario , Marín Felipe , Gómez Daniel , Hansen Felipe
Published: March 2021

The agriculture and livestock industry generate waste used in anaerobic digestion to produce biogas containing methane (CH4), useful in the generation of electricity and heat. However, although biogas is mainly composed of CH4 (~65%) and CO2 (~34%), among the 1% of other compounds present is hydrogen sulphide (H2S) which deteriorates engines and power generation fuel cells that use biogas, generating a foul smell and contaminating the environment. As a solution to this, anoxic biofiltration, specifically with biotrickling filters (BTFs), stands out in terms of the elimination of H2S as it is cost-effective, efficient, and more environmentally friendly than chemical solutions. Research on the topic is uneven in terms of presenting performance markers, underestimating many microbiological indicators. Research from the last decade was analyzed (2010–2020), demonstrating that only 56% of the reviewed publications did not report microbiological analysis related to sulphur oxidising bacteria (SOB), the most important microbial group in desulphurisation BTFs. This exposes fundamental deficiencies within this type of research and difficulties in comparing performance between research works. In this review, traditional and microbiological performance markers of anoxic biofiltration to remove H2S are described. Additionally, an analysis to assess the efficiency of anoxic BTFs for biogas desulphurisation is proposed in order to have a complete and uniform assessment for research in this field.
Spatiotemporal Patterns of Ecosystem Restoration Activities and Their Effects on Changes in Terrestrial Gross Primary Production in Southwest China
Authors: Ding Zhi , Zheng Hui , Liu Ying , Zeng Sidong , Yu Pujia , Shi Wei , Tang Xuguang
Published: March 2021

Large-scale ecosystem restoration projects (ERPs) have been implemented since the beginning of the new millennium to restore vegetation and improve the ecosystem in Southwest China. However, quantifying the effects of specific restoration activities, such as afforestation and grass planting, on vegetation recovery is difficult due to their incommensurable spatiotemporal distribution. Long-term and successive ERP-driven land use/cover changes (LUCCs) were used to recognise the spatiotemporal patterns of major restoration activities, and a contribution index was defined to assess the effects of these activities on gross primary production (GPP) dynamics in Southwest China during the period of 2001–2015. The results were as follows. (1) Afforestation and grass planting were major restoration activities that accounted for more than 54% of all LUCCs in Southwest China. Approximately 96% of restoration activities involved afforestation, and these activities were mostly distributed around Yunnan Province. (2) The Breathing Earth System Simulator (BESS) GPP performed better than the Moderate Resolution Imaging Spectroradiometer (MODIS) GPP validated by field observation data. Nevertheless, their annual GPP trends were similar and increased by 12,581 g C m−2 d−1 and 13,406 g C m−2 d−1 for MODIS and BESS GPPs, respectively. (3) Although the afforestation and grass planting areas accounted for less than 1% of the total area of Southwest China, they contributed to more than 1% of the annual GPP increase in the entire study area. Afforestation directly contributed 14.94% (BESS GPP) or 24.64% (MODIS GPP) to the annual GPP increase. Meanwhile, grass planting directly contributed only 0.41% (BESS GPP) or 0.03% (MODIS GPP) to the annual GPP increase.
Exploring VIIRS Continuity with MODIS in an Expedited Capability for Monitoring Drought-Related Vegetation Conditions
Authors: Benedict Trenton D. , Brown Jesslyn F. , Boyte Stephen P. , Howard Daniel M. , Fuchs Brian A. , Wardlow Brian D. , Tadesse Tsegaye , Evenson Kirk A.
Published: March 2021

Vegetation has been effectively monitored using remote sensing time-series vegetation index (VI) data for several decades. Drought monitoring has been a common application with algorithms tuned to capturing anomalous temporal and spatial vegetation patterns. Drought stress models, such as the Vegetation Drought Response Index (VegDRI), often use VIs like the Normalized Difference Vegetation Index (NDVI). The EROS expedited Moderate Resolution Imaging Spectroradiometer (eMODIS)-based, 7-day NDVI composites are integral to the VegDRI. As MODIS satellite platforms (Terra and Aqua) approach mission end, the Visible Infrared Imaging Radiometer Suite (VIIRS) presents an alternate NDVI source, with daily collection, similar band passes, and moderate spatial resolution. This study provides a statistical comparison between EROS expedited VIIRS (eVIIRS) 375-m and eMODIS 250-m and tests the suitability of replacing MODIS NDVI with VIIRS NDVI for drought monitoring and vegetation anomaly detection. For continuity with MODIS NDVI, we calculated a geometric mean regression adjustment algorithm using 375-m resolution for an eMODIS-like NDVI (eVIIRS’) eVIIRS’ = 0.9887 × eVIIRS − 0.0398. The resulting statistical comparisons (eVIIRS’ vs. eMODIS NDVI) showed correlations consistently greater than 0.84 throughout the three years studied. The eVIIRS’ VegDRI results characterized similar drought patterns and hotspots to the eMODIS-based VegDRI, with near zero bias.
A Method of Segmenting Apples Based on Gray-Centered RGB Color Space
Authors: Fan Pan , Lang Guodong , Yan Bin , Lei Xiaoyan , Guo Pengju , Liu Zhijie , Yang Fuzeng
Published: March 2021

In recent years, many agriculture-related problems have been evaluated with the integration of artificial intelligence techniques and remote sensing systems. The rapid and accurate identification of apple targets in an illuminated and unstructured natural orchard is still a key challenge for the picking robot’s vision system. In this paper, by combining local image features and color information, we propose a pixel patch segmentation method based on gray-centered red–green–blue (RGB) color space to address this issue. Different from the existing methods, this method presents a novel color feature selection method that accounts for the influence of illumination and shadow in apple images. By exploring both color features and local variation in apple images, the proposed method could effectively distinguish the apple fruit pixels from other pixels. Compared with the classical segmentation methods and conventional clustering algorithms as well as the popular deep-learning segmentation algorithms, the proposed method can segment apple images more accurately and effectively. The proposed method was tested on 180 apple images. It offered an average accuracy rate of 99.26%, recall rate of 98.69%, false positive rate of 0.06%, and false negative rate of 1.44%. Experimental results demonstrate the outstanding performance of the proposed method.
Interannual and Seasonal Variations of Hydrological Connectivity in a Large Shallow Wetland of North China Estimated from Landsat 8 Images
Authors: Li Ziqi , Sun Wenchao , Chen Haiyang , Xue Baolin , Yu Jingshan , Tian Zaifeng
Published: March 2021

Hydrological connectivity is an important characteristic of wetlands that maintains the stability and functions of an ecosystem. This study investigates the temporal variations of hydrological connectivity and their driving mechanism in Baiyangdian Lake, a large shallow wetland in North China, using a time series of open water surface area data derived from 36 Landsat 8 multispectral images from 2013–2019 and in situ measured water level data. Water area classification was implemented using the Google Earth Engine. Six commonly used indexes for extracting water surface data from satellite images were compared and the best performing index was selected for the water classification. A composite hydrological connectivity index computed from open water area data derived from Landsat 8 images was developed based on several landscape pattern indices and applied to Baiyangdian Lake. The results show that, reflectance in the near-infrared band is the most accurate index for water classification with >98% overall accuracy because of its sensitivity to different land cover types. The slopes of the best-fit linear relationships between the computed hydrological connectivity and observed water level show high variability between years. In most years, hydrological connectivity generally increases when water levels increase, with an average R2 of 0.88. The spatial distribution of emergent plants also varies year to year owing to interannual variations of the climate and hydrological regime. This presents a possible explanation for the variations in the annual relationship between hydrological connectivity and water level. For a given water level, the hydrological connectivity is generally higher in spring than summer and autumn. This can be explained by the fact that the drag force exerted by emergent plants, which reduces water flow, is smaller than that for summer and autumn owing to seasonal variations in the phenological characteristics of emergent plants. Our study reveals that both interannual and seasonal variations in the hydrological connectivity of Baiyangdian Lake are related to the growth of emergent plants, which occupy a large portion of the lake area. Proper vegetation management may therefore improve hydrological connectivity in this wetland.
3D Reconstruction of Coastal Cliffs from Fixed-Wing and Multi-Rotor UAS: Impact of SfM-MVS Processing Parameters, Image Redundancy and Acquisition Geometry
Authors: Gonçalves Gil , Gonçalves Diogo , Gómez-Gutiérrez Álvaro , Andriolo Umberto , Pérez-Alvárez Juan Antonio
Published: March 2021

Monitoring the dynamics of coastal cliffs is fundamental for the safety of communities, buildings, utilities, and infrastructures located near the coastline. Structure-from-Motion and Multi View Stereo (SfM-MVS) photogrammetry based on Unmanned Aerial Systems (UAS) is a flexible and cost-effective surveying technique for generating a dense 3D point cloud of the whole cliff face (from bottom to top), with high spatial and temporal resolution. In this paper, in order to generate a reproducible, reliable, precise, accurate, and dense point cloud of the cliff face, a comprehensive analysis of the SfM-MVS processing parameters, image redundancy and acquisition geometry was performed. Using two different UAS, a fixed-wing and a multi-rotor, two flight missions were executed with the aim of reconstructing the geometry of an almost vertical cliff located at the central Portuguese coast. The results indicated that optimizing the processing parameters of Agisoft Metashape can improve the 3D accuracy of the point cloud up to 2 cm. Regarding the image acquisition geometry, the high off-nadir (90°) dataset taken by the multi-rotor generated a denser and more accurate point cloud, with lesser data gaps, than that generated by the low off-nadir dataset (3°) taken by the fixed wing. Yet, it was found that reducing properly the high overlap of the image dataset acquired by the multi-rotor drone permits to get an optimal image dataset, allowing to speed up the processing time without compromising the accuracy and density of the generated point cloud. The analysis and results presented in this paper improve the knowledge required for the 3D reconstruction of coastal cliffs by UAS, providing new insights into the technical aspects needed for optimizing the monitoring surveys.
Data Assimilation of Terrestrial Water Storage Observations to Estimate Precipitation Fluxes: A Synthetic Experiment
Authors: Girotto Manuela , Reichle Rolf , Rodell Matthew , Maggioni Viviana
Published: March 2021

The Gravity Recovery and Climate Experiment (GRACE) mission and its Follow-On (GRACE-FO) mission provide unprecedented observations of terrestrial water storage (TWS) dynamics at basin to continental scales. Established GRACE data assimilation techniques directly adjust the simulated water storage components to improve the estimation of groundwater, streamflow, and snow water equivalent. Such techniques artificially add/subtract water to/from prognostic variables, thus upsetting the simulated water balance. To overcome this limitation, we propose and test an alternative assimilation scheme in which precipitation fluxes are adjusted to achieve the desired changes in simulated TWS. Using a synthetic data assimilation experiment, we show that the scheme improves performance skill in precipitation estimates in general, but that it is more robust for snowfall than for rainfall, and it fails in certain regions with strong horizontal gradients in precipitation. The results demonstrate that assimilation of TWS observations can help correct (adjust) the model’s precipitation forcing and, in turn, enhance model estimates of TWS, snow mass, soil moisture, runoff, and evaporation. A key limitation of the approach is the assumption that all errors in TWS originate from errors in precipitation. Nevertheless, the proposed approach produces more consistent improvements in simulated runoff than the established GRACE data assimilation techniques.
The Experimental Registration of the Evanescent Acoustic Wave in YX LiNbO3 Plate
Authors: Smirnov Andrey , Zaitsev Boris , Teplykh Andrey , Nedospasov Ilya , Golovanov Egor , Qian Zheng-hua , Wang Bin , Kuznetsova Iren
Published: March 2021

Evanescent acoustic waves are characterized by purely imaginary or complex wavenumbers. Earlier, in 2019 by using a three dimensional (3D) finite element method (FEM) the possibility of the excitation and registration of such waves in the piezoelectric plates was theoretically shown. In this paper the set of the acoustically isolated interdigital transducers (IDTs) with the different spatial periods for excitation and registration of the evanescent acoustic wave in Y-cut X-propagation direction of lithium niobate (LiNbO3) plate was specifically calculated and produced. As a result, the possibility to excite and register the evanescent acoustic wave in the piezoelectric plates was experimentally proved for the first time. The evanescent nature of the registered wave has been established. The theoretical results turned out to be in a good agreement with the experimental ones. The influence of an infinitely thin layer with arbitrary conductivity placed on a plate surface was also investigated. It has been shown that the frequency region of an evanescent acoustic wave existence is very sensitive to the changes of the electrical boundary conditions. The results obtained may be used for the development of the method of the analysis of thin films electric properties based on the study of evanescent waves.
Development of an Improved Rapidly Exploring Random Trees Algorithm for Static Obstacle Avoidance in Autonomous Vehicles
Authors: Yang S. M. , Lin Y. A.
Published: March 2021

Safe path planning for obstacle avoidance in autonomous vehicles has been developed. Based on the Rapidly Exploring Random Trees (RRT) algorithm, an improved algorithm integrating path pruning, smoothing, and optimization with geometric collision detection is shown to improve planning efficiency. Path pruning, a prerequisite to path smoothing, is performed to remove the redundant points generated by the random trees for a new path, without colliding with the obstacles. Path smoothing is performed to modify the path so that it becomes continuously differentiable with curvature implementable by the vehicle. Optimization is performed to select a “near”-optimal path of the shortest distance among the feasible paths for motion efficiency. In the experimental verification, both a pure pursuit steering controller and a proportional–integral speed controller are applied to keep an autonomous vehicle tracking the planned path predicted by the improved RRT algorithm. It is shown that the vehicle can successfully track the path efficiently and reach the destination safely, with an average tracking control deviation of 5.2% of the vehicle width. The path planning is also applied to lane changes, and the average deviation from the lane during and after lane changes remains within 8.3% of the vehicle width.
Evaluating the Effects of Environmental Conditions on Sensed Parameters for Green Areas Monitoring and Smart Irrigation Systems
Authors: Mauri Pedro V. , Parra Lorena , Yousfi Salima , Lloret Jaime , Marin Jose F.
Published: March 2021

The irrigation of green areas in cities should be managed appropriately to ensure its sustainability. In large cities, not all green areas might be monitored simultaneously, and the data acquisition time can skew the gathered value. Our purpose is to evaluate which parameter has a lower hourly variation. We included soil parameters (soil temperature and moisture) and plant parameters (canopy temperature and vegetation indexes). Data were gathered at 5 different hours in 11 different experimental plots with variable irrigation and with different grass composition. The results indicate that soil moisture and Normalized Difference Vegetation Index are the sole parameters not affected by the data acquisition time. For soil moisture, the maximum difference was in experimental plot 4, with values of 21% at 10:45 AM and 27% at 8:45 AM. On the other hand, canopy temperature is the most affected parameter with a mean variation of 15 °C in the morning. The maximum variation was in experimental plot 8 with a 19 °C at 8:45 AM and 39 °C at 12:45 PM. Data acquisition time affected the correlation between soil moisture and canopy temperature. We can affirm that data acquisition time has to be included as a variability source. Finally, our conclusion indicates that it is vital to consider data acquisition time to ensure water distribution for irrigation in cities.
Eligibility Classification as a Factor in Understanding Student-Athlete Responses to Collegiate Volleyball Competition
Authors: Edmonds Rohan , Schmidt Brad , Siedlik Jacob
Published: March 2021

The current study examined differences in heart rate variability (HRV) across student-athletes of different eligibility classifications and analyzed differences in HRV when competing at home or away. Fourteen female collegiate volleyball players volunteered for the study. Data collection encompassed an entire collegiate season, with comparisons in HRV made between home and away games, as well as pre-gameday, gameday, and post-gameday recordings for the whole squad. Comparisons were also made between student-athlete eligibility classification, with self-reported measures of sleep quality, fatigue, muscle soreness, stress, and mood recorded at the time of HRV measurement. Freshman athletes reported a significantly (p < 0.05, η2 = 0.17) lower HRV (80.3 ± 9.7) compared to sophomore (85.7 ± 7.2), junior (91.2 ± 8.3), and senior (86.5 ± 7.2) athletes, while junior athletes had a significantly higher HRV when compared to sophomore and senior athletes. All athlete classifications reported similar HRV for home and away games, and there was no difference in HRV for any athlete classification group when comparing pre-gameday, gameday, and post-gameday measures. Freshman athletes reported significantly (p < 0.05, η2 = 0.23) worse mood states compared to the other eligibility classifications, while self-reported stress was significantly (p < 0.05) worse in junior and senior athletes. Results suggest that monitoring the workload of student-athletes based on their eligibility classification holds merit. Collegiate coaching and support staff should be aware of the academic and competitive demands placed on their student-athletes. In particular, freshman athletes adjusting to the increased demands placed on them as collegiate student-athlete may warrant additional support.
ROS Homeostasis and Plant Salt Tolerance: Plant Nanobiotechnology Updates
Authors: Liu Jiahao , Fu Chengcheng , Li Guangjing , Khan Mohammad Nauman , Wu Honghong
Published: March 2021

Salinity is an issue impairing crop production across the globe. Under salinity stress, besides the osmotic stress and Na+ toxicity, ROS (reactive oxygen species) overaccumulation is a secondary stress which further impairs plant performance. Chloroplasts, mitochondria, the apoplast, and peroxisomes are the main ROS generation sites in salt-stressed plants. In this review, we summarize ROS generation, enzymatic and non-enzymatic antioxidant systems in salt-stressed plants, and the potential for plant biotechnology to maintain ROS homeostasis. Overall, this review summarizes the current understanding of ROS homeostasis of salt-stressed plants and highlights potential applications of plant nanobiotechnology to enhance plant tolerance to stresses.
Model of the Consumer Switching Behavior Related to Healthy Food Products
Authors: Hidayat Anas , Wijaya Tony , Ishak Asmai , Rejeki Ekasasi Sri , Zalzalah Guruh Ghifar
Published: March 2021

This study aimed to examine the effect of customers’ attitudes, subjective norms, and perceived behavior control on their intention to switch to healthy food products. This research also tested brand awareness as a moderator of customers’ behavioral choices to switch to healthy food products by switching behavior. The study was conducted by distributing a questionnaire. It involved 318 participants and employed partial least square regression as the data analysis method. This study shows the significant influence of customers’ attitudes on their switching intentions toward healthy food products, and perceived behavior control significantly influences customers’ switching intentions toward healthy food products. Customers’ perceived behavior control, as well as their intentions to switch toward healthy food products, significantly influences their switching behavior. Brand awareness has a moderate influence on customers’ intentions to switching behavior on healthy food products. This study contributes to developing the model of customer behavior in switching from fast food products to healthy food products. This study reveals that subjective norms do not significantly influence the switching behavior of customers.
Influence of Carbonization Process on the Mechanical Properties of Nano-MgO Modified Cement Soil
Authors: Wang Wei , Zhou Hang , Li Jian , Tao Feifei , Li Cuihong , Qian Biao , Jiang Ping
Published: March 2021

In order to explore the modification effect of carbonization time on nano-MgO-modified cement soil, unconfined compressive strength tests of nano-MgO-modified cement soil with carbonization times of 0 h, 6 h, 1 d, 2 d and 4 d were carried out. A method for normalizing the stress–strain curve was proposed, and the influence of nano-MgO content and carbonization time was investigated from the three aspects of compressive strength, peak strain and energy dissipation. The test results show the following: (1) The compressive strength of the modified cement soil can be significantly improved by adding 1.0% nano-MgO and after 1 d carbonization. (2) Under the same nano-MgO content, the peak strain of the modified cement soil after 2 d carbonization reaches the maximum, which can significantly increase its ductility. However, the nano-MgO content has little influence on the peak strain of the modified cement soil. (3) Under the same nano-MgO content, the energy dissipation rate of the modified cement soil after 1 d carbonization reaches the maximum, which can better resist the damage of external load.
Fertilization and Shading Trials to Promote Pinus nigra Seedlings’ Nursery Growth under the Climate Change Demands
Authors: Tsakaldimi Marianthi , Giannaki Panagiota , Ivetić Vladan , Kapsali Nikoleta , Ganatsas Petros
Published: March 2021

Pinus nigra is one of the most widely used tree species for reforestation within its geographical distribution, as well as being a potential substitute for other tree species in Central Europe under future climate scenarios. P. nigra is transplanted into the field as two-year or three-year old seedlings because of its relatively low growth rate in the nursery. This study investigated the effects of fertilization programs and shading on P. nigra seedlings, aiming to accelerate early growth, and thus to reduce the nursery rearing time. The experiment (a completely randomized block design) was conducted in an open-air nursery by sowing seeds from Grevena, Northern Greece, in Quick pots filled with peat and perlite in a 2:1 ratio. The seedlings were subjected to two levels of fertilization—5 and 10 g L−1 NPK (30-10-10)—and two shading levels: 50% and 70%. At the ends of the first and second nursery growing season, we recorded the seedlings’ above- and below-ground morphology and biomass data. The results show that the application of all of the treatments produced seedlings which met the targeted quality standards for outplanting. However, the combination of a high fertilization rate and low shading level resulted in seedlings of a higher morphological quality, which is often considered to be an indicator for a successful seedling establishment in the field.