bluuebunny/crossref_metadata_2025 huggingface dataset:
Caring for the Older Horse: A Conceptual Model of Owner Decision Making
Authors: Smith Rebecca , Pinchbeck Gina , McGowan Catherine , Ireland Joanne , Perkins Elizabeth
Published: May 2021

The number of aged horses in the UK has been growing over recent years, with many horses remaining active and being cared for into old age. However, increasing age is paralleled with a heightened risk of morbidity and mortality; therefore, owners of older horses must manage changes in their horse, making decisions about management and health care provision. In this paper, we discuss data collected from an open-access online discussion forum, where forum users sought advice arising from concerns about their older horse. Qualitative data analysis was performed using grounded theory methods. A conceptual model was developed to demonstrate the multifaceted ways in which ageing affects the human–horse relationship and impacts upon outcomes for the horse. The model reflects the dynamic nature of caring for an older horse to accommodate change over time—outcomes for the horse shift as the context of day-to-day life changes. The model provides novel insight into how decisions around older horse care are made.
Effects of Starch Level and a Mixture of Sunflower and Fish Oils on Nutrient Intake and Digestibility, Rumen Fermentation, and Ruminal Methane Emissions in Dairy Cows
Authors: Darabighane Babak , Tapio Ilma , Ventto Laura , Kairenius Piia , Stefański Tomasz , Leskinen Heidi , Shingfield Kevin , Vilkki Johanna , Bayat Ali-Reza
Published: May 2021

Four multiparous dairy cows were used in a 4 × 4 Latin square to examine how starch level and oil mixture impact dry matter (DM) intake and digestibility, milk yield and composition, rumen fermentation, ruminal methane (CH4) emissions, and microbial diversity. Experimental treatments comprised high (HS) or low (LS) levels of starch containing 0 or 30 g of a mixture of sunflower and fish oils (2:1 w/w) per kg diet DM (LSO and HSO, respectively). Intake of DM did not differ between cows fed LS and HS diets while oil supplementation reduced DM intake. Dietary treatments did not affect milk and energy corrected milk yields. There was a tendency to have a lower milk fat concentration due to HSO compared with other treatments. Both high starch level and oil supplementation increased digestibility of gross energy. Cows receiving HS diets had higher levels of total rumen VFA while acetate was lower than LS without any differences in rumen pH, or ruminal CH4 emissions. Although dietary oil supplementation had no impact on rumen fermentation, decreased CH4 emissions (g/day and g/kg milk) were observed with a concomitant increase in Anoplodinium-Diplodinium sp. and Epidinium sp. but a decrease in Christensenellaceae, Ruminococcus sp., Methanobrevibacter ruminantium and Mbb. gottschalkii clades.
Whole-Genome Sequence Analysis of Italian Honeybees (Apis mellifera)
Authors: Minozzi Giulietta , Lazzari Barbara , De Iorio Maria Grazia , Costa Cecilia , Carpana Emanuele , Crepaldi Paola , Rizzi Rita , Facchini Elena , Gandini Gustavo , Stella Alessandra , Pagnacco Giulio
Published: May 2021

At the end of the last glaciation, Apis mellifera was established in northern Europe. In Italy, Apis melliferaligustica adapted to the mild climate and to the rich floristic biodiversity. Today, with the spread of Varroa destructor and with the increasing use of pesticides in agriculture, the Ligustica subspecies is increasingly dependent on human action for its survival. In addition, the effects of globalization of bee keeping favored the spread in Italy of other honeybee stocks of A. mellifera, in particular the Buckfast bee. The purpose of this study was to characterize the Italian honeybee’s population by sequencing the whole genome of 124 honeybees. Whole genome sequencing was performed by Illumina technology, obtaining a total coverage of 3720.89X, with a mean sample coverage of 29.77X. A total of 4,380,004 SNP variants, mapping on Amel_HAv3.1 chromosomes, were detected. Results of the analysis of the patterns of genetic variation allowed us to identify and subgroup bees according to their type. The investigation revealed the genetic originality of the Sicula, and in A.m. ligustica limited genetic introgression from the other breeds. Morphometric analysis of 5800 worker bees was in agreement with genomic data.
Distinct Resistomes and Microbial Communities of Soils, Wastewater Treatment Plants and Households Suggest Development of Antibiotic Resistances Due to Distinct Environmental Conditions in Each Environment
Authors: Schages Laura , Wichern Florian , Geisen Stefan , Kalscheuer Rainer , Bockmühl Dirk
Published: May 2021

The use of antibiotics in humans and animals results in a release of excess antibiotic residues into the environment through wastewaters and insufficient removal in wastewater treatment plants (WWTP), leading to increasing numbers of bacteria enriched in antibiotic resistance genes (ARG). However, the potential transfer of ARG and their host bacteria between different environments remains largely unexplored. Since many factors need to be fulfilled for a transfer between different environments, we hypothesized that antibiotic resistance (ABR) is less frequently transferred between environments in the same geographical region but rather develops and clusters in each distinct environment, leading to characteristic metagenome patterns in samples of different environments. We sampled agricultural soils, a WWTP and private households and performed metagenomic analyses to evaluate differences and potential overlaps in bacterial communities and resistomes of different environments. Wastewater revealed significantly higher richness of ARG (n = 40) and mobile genetic elements (n = 52) than soil and household samples. Bacterial communities differed between the environments and antibiotic resistance factors clustered distinctly. Overall, only few overlaps of ARG between the environments were observed, leading to the conclusion that ABR predominantly develops in individual environments as caused by environmental filtering for ARG, while a transfer between different environments is less likely.
Use of Procalcitonin during the First Wave of COVID-19 in the Acute NHS Hospitals: A Retrospective Observational Study
Authors: Powell Neil , Howard Philip , Llewelyn Martin J. , Szakmany Tamas , Albur Mahableswhar , Bond Stuart E , Euden Joanne , Brookes-Howell Lucy , Dark Paul , Hellyer Thomas P , Hopkins Susan , McCullagh Iain J , Ogden Margaret , Pallmann Philip , Parsons Helena , Partridge David G , Shaw Dominick E. , Shinkins Bethany , Todd Stacy , Thomas-Jones Emma , West Robert , Carrol Enitan D , Sandoe Jonathan A. T.
Published: May 2021

A minority of patients presenting to hospital with COVID-19 have bacterial co-infection. Procalcitonin testing may help identify patients for whom antibiotics should be prescribed or withheld. This study describes the use of procalcitonin in English and Welsh hospitals during the first wave of the COVID-19 pandemic. A web-based survey of antimicrobial leads gathered data about the use of procalcitonin testing. Responses were received from 148/151 (98%) eligible hospitals. During the first wave of the COVID-19 pandemic, there was widespread introduction and expansion of PCT use in NHS hospitals. The number of hospitals using PCT in emergency/acute admissions rose from 17 (11%) to 74/146 (50.7%) and use in Intensive Care Units (ICU) increased from 70 (47.6%) to 124/147 (84.4%). This increase happened predominantly in March and April 2020, preceding NICE guidance. Approximately half of hospitals used PCT as a single test to guide decisions to discontinue antibiotics and half used repeated measurements. There was marked variation in the thresholds used for empiric antibiotic cessation and guidance about interpretation of values. Procalcitonin testing has been widely adopted in the NHS during the COVID-19 pandemic in an unevidenced, heterogeneous way and in conflict with relevant NICE guidance. Further research is needed urgently that assesses the impact of this change on antibiotic prescribing and patient safety.
Phage Biocontrol of Bacterial Leaf Blight Disease on Welsh Onion Caused by Xanthomonas axonopodis pv. allii
Authors: Nga Nguyen Thi Thu , Tran Tran Ngoc , Holtappels Dominique , Kim Ngan Nguyen Le , Hao Nguyen Phuoc , Vallino Marta , Tien Doan Thi Kieu , Khanh-Pham Nguyen Huan , Lavigne Rob , Kamei Kaeko , Wagemans Jeroen , Jones Jeffrey B.
Published: May 2021

Bacterial leaf blight, which is caused by Xanthomonas axonopodis pv. allii, annually causes significant yield losses to Welsh onion in many producing countries, including Vietnam. In this study, we isolated and characterized lytic phages Φ16, Φ17A and Φ31, specific to X. axonopodis pv. allii and belonging to a new phage species and genus within the Autographiviridae, from four provinces in the Mekong Delta of Vietnam. Moreover, we evaluated their efficacy for the biocontrol of leaf blight in greenhouse and field conditions. When applying the three highly related phages individually or as a three-phage cocktail at 108 PFU/mL in greenhouse conditions, our results show that treatment with Φ31 alone provides higher disease prevention than the two other phages or the phage cocktail. Furthermore, we compared phage concentrations from 105 to 108 and showed optimal disease control at 107 and 108 PFU/mL. Finally, under field conditions, both phage Φ31 alone and the phage cocktail treatments suppressed disease symptoms, which was comparable to the chemical bactericide oxolinic acid (Starner). Phage treatment also significantly improved yield, showing the potential of phage as a biocontrol strategy for managing leaf blight in Welsh onion.
Phenotypic and Molecular Traits of Staphylococcus coagulans Associated with Canine Skin Infections in Portugal
Authors: Costa Sofia Santos , Oliveira Valéria , Serrano Maria , Pomba Constança , Couto Isabel
Published: May 2021

Staphylococcus coagulans is among the three most frequent pathogens of canine pyoderma. Yet, studies on this species are scarce. Twenty-seven S. coagulans and one S. schleiferi, corresponding to all pyoderma-related isolations from these two species at two veterinary laboratories in Lisbon, Portugal, between 1999 and 2018 (Lab 1) or 2018 (Lab 2), were analyzed. Isolates were identified by the analysis of the nuc gene and urease production. Antibiotic susceptibility towards 27 antibiotics was evaluated by disk diffusion. Fourteen antibiotic resistance genes were screened by PCR. Isolates were typed by SmaI-PFGE. Two S. coagulans isolates (2/27, 7.4%) were methicillin-resistant (MRSC, mecA+) and four (4/27, 14.8%) displayed a multidrug-resistant (MDR) phenotype. We observed resistance to penicillin (17/27, 63.0%), fluoroquinolones (11/27, 40.7%), erythromycin and clindamycin (3/27, 11.1%), fusidic acid (3/27, 11.1%) and tetracycline (1/27, 3.7%). The blaZ and erm(B) genes were carried by 16 and 1 isolates resistant to penicillin and erythromycin/clindamycin, respectively. Only three S. coagulans carried plasmids. The single S. schleiferi isolate presented an MDR phenotype. SmaI-PFGE revealed a limited genetic diversity of S. coagulans, with a predominant lineage present from 2001 to 2018. This study describes the first MRSC causing canine infection in Portugal and reveals a high burden of antimicrobial resistance, with the emergence of MDR phenotypes within the main lineages.
Pilot Study on Alteration of LA-MRSA Status of Pigs during Fattening Period on Straw Bedding by Two Types of Cleaning
Authors: Schollenbruch Hannah , Kobusch Iris , Schröter Iris , Mellmann Alexander , Köck Robin , Boelhauve Marc
Published: May 2021

In countries with professional pig husbandry in stables, the prevalence of livestock-associated (LA) methicillin-resistant Staphylococcus aureus (MRSA) on farms has remained high or has further increased in recent years. Simple measures to reduce LA-MRSA among pigs have not yet been successfully implemented. The aim of this pilot study is twofold: first, to examine how the LA-MRSA status of LA-MRSA positive fattening pigs at the date of housing changes over the fatting period on straw bedding and, second, whether this change could be influenced by the quality of cleaning and disinfection (C&D). For this purpose, 122 animals are individually tested for LA-MRSA carriage at five sequential time points comparing pigs housed on a farm using straw bedding plus C&D (n = 59) vs. straw bedding plus simple cleaning (n = 63). At the time of housing, all animals in both groups are LA-MRSA positive. This status changes to 0% in the group with simple cleaning until the end of fattening and 28% in the C&D group. LA-MRSA in environmental and air samples is also reduced over the fattening period. The results indicate that keeping pigs on straw might be one way to reduce LA-MRSA during the fattening period with simple cleaning appearing to be more beneficial than C&D. Further investigations are necessary to determine the influencing factors more precisely.
Heterogeneity of Antibiotics Multidrug-Resistance Profile of Uropathogens in Romanian Population
Authors: Petca Răzvan-Cosmin , Negoiță Silvius , Mareș Cristian , Petca Aida , Popescu Răzvan-Ionuț , Chibelean Călin Bogdan
Published: May 2021

Urinary tract infections (UTIs) are a leading cause of morbidity for both males and females. The overconsumption of antibiotics in general medicine, veterinary, or agriculture has led to a spike in drug-resistant microorganisms; obtaining standardized results is imposed by standard definitions for various categories of drug-resistant bacteria—such as multiple-drug resistant (MDR), extensive drug-resistant (XDR), and pan drug-resistant (PDR). This retrospective study conducted in three university teaching hospitals in Romania has analyzed urine probes from 15,231 patients, of which 698 (4.58%) presented multidrug-resistant strains. Escherichia coli was the leading uropathogen 283 (40.54%), presenting the highest resistance to quinolones (R = 72.08%) and penicillin (R = 66.78%) with the most important patterns of resistance for penicillin, sulfonamides, and quinolones (12.01%) and aminoglycosides, aztreonam, cephalosporins, and quinolones (9.89%). Klebsiella spp. followed—260 (37.24%) with the highest resistance to amoxicillin-clavulanate (R = 94.61%) and cephalosporins (R = 94.23%); the leading patterns were observed for aminoglycosides, aminopenicillins + β-lactams inhibitor, sulfonamides, and cephalosporins (12.69%) and aminoglycosides, aztreonam, cephalosporins, quinolones (9.23%). The insufficient research of MDR strains on the Romanian population is promoting these findings as an important tool for any clinician treating MDR-UTIs.
Methylglyoxal-Dependent Glycative Stress Is Prevented by the Natural Antioxidant Oleuropein in Human Dental Pulp Stem Cells through Nrf2/Glo1 Pathway
Authors: Delle Monache Simona , Pulcini Fanny , Frosini Roberta , Mattei Vincenzo , Talesa Vincenzo Nicola , Antognelli Cinzia
Published: May 2021

Methylglyoxal (MG) is a potent precursor of glycative stress (abnormal accumulation of advanced glycation end products, AGEs), a relevant condition underpinning the etiology of several diseases, including those of the oral cave. At present, synthetic agents able to trap MG are known; however, they have never been approved for clinical use because of their severe side effects. Hence, the search of bioactive natural scavengers remains a sector of strong research interest. Here, we investigated whether and how oleuropein (OP), the major bioactive component of olive leaf, was able to prevent MG-dependent glycative stress in human dental pulp stem cells (DPSCs). The cells were exposed to OP at 50 µM for 24 h prior to the administration of MG at 300 µM for additional 24 h. We found that OP prevented MG-induced glycative stress and DPSCs impairment by restoring the activity of Glyoxalase 1 (Glo1), the major detoxifying enzyme of MG, in a mechanism involving the redox-sensitive transcription factor Nrf2. Our results suggest that OP holds great promise for the development of preventive strategies for MG-derived AGEs-associated oral diseases and open new paths in research concerning additional studies on the protective potential of this secoiridoid.
Analytical Solutions of the Diffusion–Wave Equation of Groundwater Flow with Distributed-Order of Atangana–Baleanu Fractional Derivative
Authors: Shah Nehad Ali , Rauf Abdul , Vieru Dumitru , Sitthithakerngkiet Kanokwan , Kumam Poom
Published: May 2021

A generalized mathematical model of the radial groundwater flow to or from a well is studied using the time-fractional derivative with Mittag-Lefler kernel. Two temporal orders of fractional derivatives which characterize small and large pores are considered in the fractional diffusion–wave equation. New analytical solutions to the distributed-order fractional diffusion–wave equation are determined using the Laplace and Dirichlet-Weber integral transforms. The influence of the fractional parameters on the radial groundwater flow is analyzed by numerical calculations and graphical illustrations are obtained with the software Mathcad.
The Importance of Intraoperative Plain Radiographs during Cochlear Implant Surgery in Patients with Normal Anatomy
Authors: Cohen Ohad , Sichel Jean-Yves , Shaul Chanan , Chen Itay , Roland J. Thomas , Perez Ronen
Published: May 2021

Although malpositioning of the cochlear implant (CI) electrode array is rare in patients with normal anatomy, when occurring it may result in reduced hearing outcome. In addition to intraoperative electrophysiologic tests, imaging is an important modality to assess correct electrode array placement. The purpose of this report was to assess the incidence and describe cases in which intraoperative plain radiographs detected a malpositioned array. Intraoperative anti-Stenver’s view plain X-rays are conducted routinely in all CI surgeries in our tertiary center before awakening the patient and breaking the sterile field. Data of patients undergoing 399 CI surgeries were retrospectively analyzed. A total of 355 had normal inner ear and temporal bone anatomy. Patients with intra or extracochlear malpositioned electrode arrays demonstrated in the intraoperative X-ray were described. There were four cases of electrode array malposition out of 355 implantations with normal anatomy (1.1%): two tip fold-overs, one extracochlear placement and one partial insertion. All electrodes were reinserted immediately; repeated radiographs were normal and the patients achieved good hearing function. Intraoperative plain anti-Stenver’s view X-rays are valuable to confirm electrode array location, allowing correction before the conclusion of surgery. These radiographs are cheaper, faster, and emit much less radiation than other imaging options, making them a viable cost-effective tool in patients with normal anatomy.
Sustainable Agriculture and Soil Conservation
Authors: Castellini Mirko , Diacono Mariangela , Gattullo Concetta Eliana , Stellacci Anna Maria
Published: May 2021

Soil degradation is one of the most topical environmental threats. A number of processes causing soil degradation, specifically erosion, compaction, salinization, pollution, and loss of both organic matter and soil biodiversity, are also strictly connected to agricultural activity and its intensification. The development and adoption of sustainable agronomic practices able to preserve and enhance the physical, chemical, and biological properties of soils and improve agroecosystem functions is a challenge for both scientists and farmers. This Special Issue collects 12 original contributions addressing the state of the art of sustainable agriculture and soil conservation. The papers cover a wide range of topics, including organic agriculture, soil amendment and soil organic carbon (SOC) management, the impact of SOC on soil water repellency, the effects of soil tillage on the quantity of SOC associated with several fractions of soil particles and depth, and SOC prediction, using visible and near-infrared spectra and multivariate modeling. Moreover, the effects of some soil contaminants (e.g., crude oil, tungsten, copper, and polycyclic aromatic hydrocarbons) are discussed or reviewed in light of the recent literature. The collection of the manuscripts presented in this Special Issue provides a relevant knowledge contribution for improving our understanding on sustainable agriculture and soil conservation, thus stimulating new views on this main topic.
Influence of Ag Electrodes Asymmetry Arrangement on Their Erosion Wear and Nanoparticle Synthesis in Spark Discharge
Authors: Khabarov Kirill , Urazov Maxim , Lizunova Anna , Kameneva Ekaterina , Efimov Alexey , Ivanov Victor
Published: May 2021

For nanoparticle synthesis in a spark discharge, the influence of the degree of electrode asymmetry in the rod-to-rod configuration, using the example of silver electrodes, on the energy efficiency and nanoparticle composition is studied. The asymmetry degree was determined by the angle between electrodes’ end faces. Two types of discharge current pulses were used: oscillation-damped and unipolar, in which electrodes changed their polarities and had a constant polarity during a single discharge, respectively. A significant influence of the asymmetry degree of the electrode arrangement on the synthesized nanoparticle size, agglomeration and concentration, and on the synthesis energy efficiency, has been established. An increase in the degree of the electrode asymmetry with the oscillation-damped discharge current pulse led to an increased mass production rate and energy efficiency of nanoparticle synthesis, a significant fraction of which had large dimensions of more than 40 nm. The effect of the transfer of synthesized nanoparticles to the opposite electrode at the unipolar discharge current pulse led to the appearance of electroerosive instability, manifested in the formation of a protrusion on the anode surface, around which spark discharges, leading to its further growth and electrode gap closure.
Novel Wilkinson Power Divider with an Isolation Resistor on a Defected Ground Structure with Improved Isolation
Authors: Salman Maaz , Jang Youna , Lim Jongsik , Ahn Dal , Han Sang-Min
Published: May 2021

A modified Wilkinson Power Divider is proposed in this paper that utilizes defected ground structure (DGS) in parallel with an isolation resistor. The proposed DGS section is incorporated between the output ports, and the isolation resistor is soldered in parallel with the DGS in the ground plane, instead of on the top plane as in a conventional Wilkinson power divider, to achieve improved or preferable isolation. The proposed design is comprised of two pairs of microstrip transmission lines with equal impedances and varied electrical lengths. The parameters of the main circuit and the DGS section are acquired separately. The parameters of the proposed main circuit are derived by applying conjugate matching theory. Dumbbell-shaped DGS is introduced in the ground plane between the output ports, which acts as a parallel resonator, yielding an attenuation pole at the resonant frequency that contributes to improved isolation. By applying the previous well-known circuit theory, the lumped elements of the equivalent circuit of the DGS were achieved. The physical dimensions of the equivalent circuit for the DGS section were obtained by three-dimensional EM simulation. The measured results show improved isolation, return loss and better bandwidth as compared with other similar works. Furthermore, the proposed circuits designed at resonating frequencies of 3 and 2 GHz presented comparatively good return losses, S11 of about −25.54 and −31.24 dB, respectively, and achieved improved isolations, S32 between the output ports, in an order of about −40.83 and −36.05 dB, respectively, which is rather exceptional and desirable.
Analysis of the Frequency Interaction of the Turbine Block in the Stand for the Magnitude of the Error in Measuring the Turbine’s Power
Authors: Petrochenkov Anton , Sal’nikov Aleksey , Bochkarev Sergey , Ilyushin Pavel
Published: May 2021

An algorithm for constructing a dynamic analysis during the formation of a wave field of stand for testing turbines and the effect of the frequency interaction of the stand’s elements on the measurement of its magnitude is described. The research algorithm involves the use of theoretical solutions of nonlinear wave processes using linear oscillations, refined by experiments. The diagnostic model can determine the technical condition of the stand’s elements and also determine the causes of the discrepancies between the calculated and measured turbine power values. To clarify the stiffness coefficients between the stand’s elements, a modal analysis was used to obtain the range of their changes depending on the external dynamic load, which made it possible to assess the impact of changes in the frequency interaction conditions on the turbine power measurement at different test modes. The conditions for amplifying the amplitude of oscillations at their eigenfrequencies are obtained, and the value of the possible deviation of the expected power value at its measurement for specific modes of the turbine is calculated. The algorithm allows to estimate the dynamic state of the stand-in different research modes of turbines and give recommendations for reducing the level of frequency interaction.
Analysis of Earth Pressure Variation for Partial Displacement of Retaining Wall
Authors: Zhang Hongbo , Liu Mingpeng , Zhou Pengfei , Zhao Zhizhong , Li Xiaoliang , Xu Xiaobin , Song Xiuguang
Published: May 2021

Parts of the retaining wall might produce displacement under different load conditions. The moveable wall could impact the adjacent fixed wall, mainly reflecting on the variation of earth pressure and formation of the soil arching effect. This paper conducted the horizontal trap-door test to explore the variation of active earth pressure caused by partial displacement of the retaining wall. Different trap-door width and three displacement modes were addressed as the influence factors. The results indicated that the horizontal soil arching effect was generated after the active displacement of the trap-door and the soil pressure was redistributed. The distribution of lateral soil pressure was approximately an “inverted bell” curve. For trap-door widths of 20 cm, 30 cm, and 40 cm, a secondary soil arching effect appeared in the test. The relationship between lateral earth pressure and displacement was different with the traditional limited theory due to the influence of the soil arching effect. The variation curve of earth pressure corresponding to displacement could be divided into three stages. In addition, the distribution of earth pressure along the trap-door height was non-linear. Trap-door width can significantly influence the maximum earth pressure on the fixed wall and the range where pressure changes. Finally, the effect of load sharing was explored and found to be related with displacement and width of trap-door as well as the displacement mode.
Activity Recognition with Combination of Deeply Learned Visual Attention and Pose Estimation
Authors: Kim Jisu , Lee Deokwoo
Published: May 2021

While human activity recognition and pose estimation are closely related, these two issues are usually treated as separate tasks. In this thesis, two-dimension and three-dimension pose estimation is obtained for human activity recognition in a video sequence, and final activity is determined by combining it with an activity algorithm with visual attention. Two problems can be solved efficiently using a single architecture. It is also shown that end-to-end optimization leads to much higher accuracy than separated learning. The proposed architecture can be trained seamlessly with different categories of data. For visual attention, soft visual attention is used, and a multilayer recurrent neural network using long short term memory that can be used both temporally and spatially is used. The image, pose estimated skeleton, and RGB-based activity recognition data are all synthesized to determine the final activity to increase reliability. Visual attention evaluates the model in UCF-11 (Youtube Action), HMDB-51 and Hollywood2 data sets, and analyzes how to focus according to the scene and task the model is performing. Pose estimation and activity recognition are tested and analyzed on MPII, Human3.6M, Penn Action and NTU data sets. Test results are Penn Action 98.9%, NTU 87.9%, and NW-UCLA 88.6%.
Soil Erosion Assessment and Prediction in Urban Landscapes: A New G2 Model Approach
Authors: Polovina Siniša , Radić Boris , Ristić Ratko , Kovačević Jovan , Milčanović Vukašin , Živanović Nikola
Published: May 2021

Soil erosion is a global problem that negatively affects the quality of the environment, the availability of natural resources, as well as the safety of inhabitants. Soil erosion threatens the functioning of urban areas, which was the reason for choosing the territory of the Master Plan of Belgrade (Serbia) as the research area. The calculation of soil erosion loss was analyzed using the G2 erosion model. The model belongs to a group of empirical models and is based on the synthesis of the equation from the Revised Universal Soil Loss Equation (RUSLE) and the Erosion Potential Method (EPM). The estimation of soil degradation was analyzed in two time periods (2001 and 2019), which represent the time boundaries of the management of the Master Plan of Belgrade. The novel approach used in this research is based on using the land cover inventory as a dynamic indicator of the urbanization process. Land cover was identified using remote sensing, machine learning techniques, and the random forest algorithm applied to multispectral satellite images of the Landsat mission in combination with spectral indices. Climatic parameters were analyzed on the basis of data from meteorological stations (first scenario, i.e., 2001), as well as on simulations of changes based on climate scenario RCP8.5 (representative concentration pathways) concerning the current condition of the land cover (second scenario). A comparative analysis of the two time periods identified a slight reduction in total soil loss. For the first period, the average soil loss value is 4.11 t·ha−1·y−1. The analysis of the second period revealed an average value of 3.63 t·ha−1·y−1. However, the increase in non-porous surfaces has led to a change in the focus of soil degradation. Increased average soil loss as one of the catalysts of torrential flood frequencies registered on natural and semi-natural areas were 43.29% and 16.14%, respectively. These results are a significant contribution to the study of soil erosion in urban conditions under the impact of climate change.
Method of Estimation of Turbulence Integral Parameters
Authors: Shen Hong , Yu Longkun , Jing Xu , Tan Fengfu
Published: May 2021

The optical effects of turbulence are directly related to turbulence integral parameters, which are integrals of the refractive index structure constant over a whole path with different path-weighting functions (PWFs). We describe a method that utilizes measurable turbulence integral parameters, such as angle-of-arrival fluctuations and scintillation, to estimate turbulence integral parameters that cannot be measured directly. The estimates of the turbulence integral parameters are based on the linear combination of the PWFs of those measurable quantities. New measurable quantities and their PWFs under different propagation conditions were studied. Some interesting and meaningful results have been obtained. This method shows the prospect of characterizing anisoplanatism in adaptive optics and allows for the estimation of some optical turbulence parameters under non-ideal conditions, such as an isoplanatic angle in a finite distance.
A Comprehensive Review of Retinal Vascular and Optical Nerve Diseases Based on Optical Coherence Tomography Angiography
Authors: Taher Fatma , Kandil Heba , Mahmoud Hatem , Mahmoud Ali , Shalaby Ahmed , Ghazal Mohammed , Alhalabi Marah Talal , Sandhu Harpal Singh , El-Baz Ayman
Published: May 2021

The optical coherence tomography angiography (OCTA) is a noninvasive imaging technology which aims at imaging blood vessels in retina by studying decorrelation signals between multiple sequential OCT B-scans captured in the same cross section. Obtaining various vascular plexuses including deep and superficial choriocapillaris, is possible, which helps in understanding the ischemic processes that affect different retina layers. OCTA is a safe imaging modality that does not use dye. OCTA is also fast as it can capture high-resolution images in just seconds. Additionally, it is used in the assessment of structure and blood flow. OCTA provides anatomic details in addition to the vascular flow data. These details are important in understanding the tissue perfusion, specifically, in the absence of apparent morphological change. Using these anatomical details along with perfusion data, OCTA could be used in predicting several ophthalmic diseases. In this paper, we review the OCTA techniques and their ability to detect and diagnose several retinal vascular and optical nerve diseases, such as diabetic retinopathy (DR), anterior ischemic optic neuropathy (AION), age-related macular degeneration (AMD), glaucoma, retinal artery occlusion and retinal vein occlusion. Then, we discuss the main features and disadvantages of using OCTA as a retinal imaging method.
Real-Time Hand Gesture Recognition Based on Deep Learning YOLOv3 Model
Authors: Mujahid Abdullah , Awan Mazhar Javed , Yasin Awais , Mohammed Mazin Abed , Damaševičius Robertas , Maskeliūnas Rytis , Abdulkareem Karrar Hameed
Published: May 2021

Using gestures can help people with certain disabilities in communicating with other people. This paper proposes a lightweight model based on YOLO (You Only Look Once) v3 and DarkNet-53 convolutional neural networks for gesture recognition without additional preprocessing, image filtering, and enhancement of images. The proposed model achieved high accuracy even in a complex environment, and it successfully detected gestures even in low-resolution picture mode. The proposed model was evaluated on a labeled dataset of hand gestures in both Pascal VOC and YOLO format. We achieved better results by extracting features from the hand and recognized hand gestures of our proposed YOLOv3 based model with accuracy, precision, recall, and an F-1 score of 97.68, 94.88, 98.66, and 96.70%, respectively. Further, we compared our model with Single Shot Detector (SSD) and Visual Geometry Group (VGG16), which achieved an accuracy between 82 and 85%. The trained model can be used for real-time detection, both for static hand images and dynamic gestures recorded on a video.
Target Recovery for Robust Deep Learning-Based Person Following in Mobile Robots: Online Trajectory Prediction
Authors: Algabri Redhwan , Choi Mun-Taek
Published: May 2021

The ability to predict a person’s trajectory and recover a target person in the event the target moves out of the field of view of the robot’s camera is an important requirement for mobile robots designed to follow a specific person in the workspace. This paper describes an extended work of an online learning framework for trajectory prediction and recovery, integrated with a deep learning-based person-following system. The proposed framework first detects and tracks persons in real time using the single-shot multibox detector deep neural network. It then estimates the real-world positions of the persons by using a point cloud and identifies the target person to be followed by extracting the clothes color using the hue-saturation-value model. The framework allows the robot to learn online the target trajectory prediction according to the historical path of the target person. The global and local path planners create robot trajectories that follow the target while avoiding static and dynamic obstacles, all of which are elaborately designed in the state machine control. We conducted intensive experiments in a realistic environment with multiple people and sharp corners behind which the target person may quickly disappear. The experimental results demonstrated the effectiveness and practicability of the proposed framework in the given environment.
A Comparative Study of Polypyrrole and Ag/Polypyrrole Hybrid Nanocomposites as Sensitive Material Used for New Dry Polarizable Bioimpedance Sensors
Authors: Telipan Gabriela , Pîslaru-Dănescu Lucian , Lungulescu Eduard-Marius , Ion Ioana , Marinescu Virgil
Published: May 2021

Three types of dry polarizable electric bioimpedance sensor for skin bioimpedance monitoring without skin preparation have been developed. The sensitive materials as a component of these sensors are the conductive polypyrrole and hybrid nanocomposite polypyrrole-Ag, with 10% and 20% Ag incorporated in the polypyrrole matrix. The hybrid nanocomposites Ag nanoparticles (NPs)/polypyrrole were obtained by introducing the colloid solution of Ag NPs in pyrrole solution, followed by polymerisation, and calculated for 10% and 20% of monomer’s mass. The structural characterisation and morphological analysis of these sensitive materials were carried-out by Raman spectrometry, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. In making the electrodes, the technique of pressing powders of polypyrrole and hybrid composites Ag NPs/polypyrrole in a hydraulic press was used in the form of a disk. The electric bioimpedance performance of sensors was investigated using a two-point method in the frequency range of 1–300 kHz, at a voltage of 2 Vpeak-peak, on six human subjects, three men and three women. For these three bioimpedance sensors, it was found that the electric bioimpedance of the skin decreases across the frequency range and shows good linearity of the impedance-frequency curve on the range frequency of interest in bioimpedance measurements.
Cell/Module Integration Technology with Wire-Embedded EVA Sheet
Authors: Park Jeong Eun , Choi Won Seok , Lim Donggun
Published: May 2021

Silicon wafers are crucial for determining the price of solar cell modules. To reduce the manufacturing cost of photovoltaic devices, the thicknesses of wafers are reduced. However, the conventional module manufacturing method using the tabbing process has a disadvantage in that the cell is damaged because of the high temperature and pressure of the soldering process, which is complicated, thus increasing the process cost. Consequently, when the wafer is thinned, the breakage rate increases during the module process, resulting in a lower yield; further, the module performance decreases owing to cracks and thermal stress. To solve this problem, a module manufacturing method is proposed in which cells and wires are bonded through the lamination process. This method minimizes the thermal damage and mechanical stress applied to solar cells during the tabbing process, thereby manufacturing high-power modules. When adopting this method, the front electrode should be customized because it requires busbarless solar cells different from the existing busbar solar cells. Accordingly, the front electrode was designed using various simulation programs such as Griddler 2.5 and MathCAD, and the effect of the diameter and number of wires in contact with the front finger line of the solar cell on the module characteristics was analyzed. Consequently, the efficiency of the module manufactured with 12 wires and a wire diameter of 0.36 mm exhibited the highest efficiency at 20.28%. This is because even if the optical loss increases with the diameter of the wire, the series resistance considerably decreases rather than the loss of the short-circuit current, thereby improving the fill factor. The characteristics of the wire-embedded ethylene vinyl acetate (EVA) sheet module were confirmed to be better than those of the five busbar tabbing modules manufactured by the tabbing process; further, a high-power module that sufficiently compensated for the disadvantages of the tabbing module was manufactured.
Air Quality in Southeast Brazil during COVID-19 Lockdown: A Combined Satellite and Ground-Based Data Analysis
Authors: Brandao Rayssa , Foroutan Hosein
Published: May 2021

With the current COVID-19 pandemic being spread all over the world, lockdown measures are being implemented, making air pollution levels go down in several countries. In this context, the air quality changes in the highly populated and trafficked Brazilian states of São Paulo (SP) and Rio de Janeiro (RJ) were addressed using a combination of satellite and ground-based daily data analysis. We explored nitrogen dioxide (NO2) and fine particulate matter (PM2.5) daily levels for the month of May from 2015–2020. Daily measurements of NO2 column concentrations from the Ozone Monitoring Instrument (OMI) aboard NASA’s Aura satellite were analyzed and decreases of 42% and 49.6% were found for SP and RJ, respectively, during the year 2020 compared to the 2015–2019 average. Besides NO2 column retrievals, ground-based data measured by the Brazilian States Environmental Institutions were analyzed and correlated with satellite retrievals. Correlation coefficients between year-to-year changes in satellite column and ground-based concentrations were 77% and 53% in SP and RJ, respectively. Ground-based data showed 13.3% and 18.8% decrease in NO2 levels for SP and RJ, respectively, in 2020 compared to 2019. In SP, no significant change in PM2.5 was observed in 2020 compared to 2019. To further isolate the effect of emissions reduction due to the lockdown, meteorological data and number of wildfire hotspots were analyzed. NO2 concentrations showed negative and positive correlations with wind speed and temperature, respectively. PM2.5 concentration distributions suggested an influence by the wildfires in the southeast region of the country. Synergistic analyses of satellite retrievals, surface level concentrations, and weather data provide a more complete picture of changes to pollutant levels.
Visual Weather Property Prediction by Multi-Task Learning and Two-Dimensional RNNs
Authors: Chu Wei-Ta , Liang Yu-Hsuan , Ho Kai-Chia
Published: May 2021

We attempted to employ convolutional neural networks to extract visual features and developed recurrent neural networks for weather property estimation using only image data. Four common weather properties are estimated, i.e., temperature, humidity, visibility, and wind speed. Based on the success of previous works on temperature prediction, we extended them in terms of two aspects. First, by considering the effectiveness of deep multi-task learning, we jointly estimated four weather properties on the basis of the same visual information. Second, we propose that weather property estimations considering temporal evolution can be conducted from two perspectives, i.e., day-wise or hour-wise. A two-dimensional recurrent neural network is thus proposed to unify the two perspectives. In the evaluation, we show that better prediction accuracy can be obtained compared to the state-of-the-art models. We believe that the proposed approach is the first visual weather property estimation model trained based on multi-task learning.
Speciation of Magnesium in Aerosols Using X-ray Absorption Near-Edge Structure Related to Its Contribution to Neutralization Reactions in the Atmosphere
Authors: Kawai Takahiro , Yamakawa Yoshiaki , Takahashi Yoshio
Published: May 2021

Aerosols, including mineral dust, are transported from China and Mongolia to Japan, particularly in spring. It has been recognized that calcium (Ca) carbonate is the main Ca species in aerosols, which reacts with acidic species such as sulfuric and nitric acids at the surface of mineral dust during its long-range transport, related to mitigation of acid depositions. The similar assumption that magnesium (Mg) originally takes the form of carbonate and contributes to the neutralization reaction and buffering effect on the acidity of aerosols has been suggested in various studies. However, few studies have confirmed this process by measuring actual Mg species in aerosols quantitatively. In this study, X-ray absorption near-edge structure (XANES) spectroscopy was employed to determine Mg species in size-fractionated aerosol samples, including mineral dust. The results showed that (i) most Mg in the mineral dust did not take the form of carbonate and its reacted species (e.g., sulfate and nitrate) produced by the neutralization reaction, but (ii) Mg was mainly found as Mg in the octahedral layer in phyllosilicates. Given that the reactivity of such Mg in phyllosilicates is much lower than those in carbonate minerals, the contribution of Mg to the neutralization reactions in the atmosphere must be lower than previously expected.
Sea Surface Temperature Variability over the Tropical Indian Ocean during the ENSO and IOD Events in 2016 and 2017
Authors: Khan Sartaj , Piao Shengchun , Zheng Guangxue , Khan Imran Ullah , Bradley David , Khan Shazia , Song Yang
Published: May 2021

2016 and 2017 were marked by strong El Niño and weak La Niña events, respectively, in the tropical East Pacific Ocean. The strong El Niño and weak La Niña events in the Pacific significantly impacted the sea surface temperature (SST) in the tropical Indian Ocean (TIO) and were followed by extreme negative and weak positive Indian Ocean Dipole (IOD) phases in 2016 and 2017, which triggered floods in the Indian subcontinent and drought conditions in East Africa. The IOD is an irregular and periodic oscillation in the Indian Ocean, which has attracted much attention in the last two decades due to its impact on the climate in surrounding landmasses. Much work has been done in the past to investigate global climate change and its impact on the evolution of IOD. The dynamic behind it, however, is still not well understood. The present study, using various satellite datasets, examined and analyzed the dynamics behind these events and their impacts on SST variability in the TIO. For this study, the monthly mean SST data was provided by NOAA Optimum Interpolation Sea Surface Temperature (OISST). SST anomalies were measured on the basis of 30-year mean daily climatology (1981–2010). It was determined that the eastern and western poles of the TIO play quite different roles during the sequence of negative and positive IOD phases. The analysis of air-sea interactions and the relationship between wind and SST suggested that SST is primarily controlled by wind force in the West pole. On the other hand, the high SST that occurred during the negative IOD phase induced local convection and westerly wind anomalies via the Bjerknes feedback mechanism. The strong convection, which was confined to the (warm) eastern equatorial Indian Ocean was accompanied by east–west SST anomalies that drove a series of downwelling Kelvin waves that deepened the thermocline in the east. Another notable feature of this study was its observation of weak upwelling along the Omani–Arabian coast, which warmed the SST by 1 °C in the summer of 2017 (as compared to 2016). This warming led to increased precipitation in the Bay of Bengal (BoB) region during the summer of 2017. The results of the present work will be important for the study of monsoons and may be useful in predicting both droughts and floods in landmasses in the vicinity of the Indian Ocean, especially in the Indian subcontinent and East African regions.