bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Implementation of the Irie Homes Toolbox: A Violence Prevention, Early Childhood, Parenting Program
Authors: Francis Taja , Baker-Henningham Helen
Published: November 2020

This paper describes the development of the Irie Homes Toolbox, a violence prevention program targeting parents of children aged two to six years. The intervention was designed to complement an existing, teacher-training, violence prevention program, the Irie Classroom Toolbox, thus promoting an integrated approach across home and school settings. The Irie Homes Toolbox was developed through a four-stage process by integrating data from theory, formative research, and practice to ensure the intervention is acceptable, feasible, relevant, and effective in the context. The perspectives of Jamaican preschool teachers and parents of preschool children, who are the end users, were integrated into the design of the intervention throughout the development process. Stage one involved integrating theory and formative research to inform the initial intervention design. Stages two and three involved iterative cycles of design, implementation and evaluation of the intervention content, process of delivery, structure and materials. Stage four involved a further cycle of learning through a process evaluation conducted as part of a cluster-randomized controlled trial. Data from each of these four stages was used to inform the design and ongoing revisions of the toolbox with the aim of developing a low-cost, scalable and sustainable intervention for the Jamaican context. The resulting program is theory-informed and uses empirically derived content and behavior change principles operationalized for the context in which it will be delivered. The Irie Homes Toolbox is suitable for integration into the existing preschool provision in Jamaica, thus utilizing an existing service and existing staff and increasing the likelihood for wide-scale dissemination.
Deep Learning for Understanding Satellite Imagery: An Experimental Survey
Authors: Mohanty Sharada Prasanna , Czakon Jakub , Kaczmarek Kamil A. , Pyskir Andrzej , Tarasiewicz Piotr , Kunwar Saket , Rohrbach Janick , Luo Dave , Prasad Manjunath , Fleer Sascha , Göpfert Jan Philip , Tandon Akshat , Mollard Guillaume , Rayaprolu Nikhil , Salathe Marcel , Schilling Malte
Published: November 2020

Translating satellite imagery into maps requires intensive effort and time, especially leading to inaccurate maps of the affected regions during disaster and conflict. The combination of availability of recent datasets and advances in computer vision made through deep learning paved the way toward automated satellite image translation. To facilitate research in this direction, we introduce the Satellite Imagery Competition using a modified SpaceNet dataset. Participants had to come up with different segmentation models to detect positions of buildings on satellite images. In this work, we present five approaches based on improvements of U-Net and Mask R-Convolutional Neuronal Networks models, coupled with unique training adaptations using boosting algorithms, morphological filter, Conditional Random Fields and custom losses. The good results—as high as AP=0.937 and AR=0.959—from these models demonstrate the feasibility of Deep Learning in automated satellite image annotation.
Modalflow: Cross-Origin Flow Data Visualization for Urban Mobility
Authors: Pérez-Messina Ignacio , Graells-Garrido Eduardo , Lobo María Jesús , Hurter Christophe
Published: November 2020

Pervasive data have become a key source of information for mobility and transportation analyses. However, as a secondary source, it has a different methodological origin than travel survey data, usually relying on unsupervised algorithms, and so it requires to be assessed as a dataset. This assessment is challenging, because, in general, there is not a benchmark dataset or a ground truth scenario available, as travel surveys only represent a partial view of the phenomenon and suffer from their own biases. For this critical task, which involves urban planners and data scientists, we study the design space of the visualization of cross-origin, multivariate flow datasets. For this purpose, we introduce the Modalflow system, which incorporates and adapts different visualization techniques in a notebook-like setting, presenting novel visual encodings and interactions for flows with modal partition into scatterplots, flow maps, origin-destination matrices, and ternary plots. Using this system, we extract general insights on visual analysis of pervasive and survey data for urban mobility and assess a mobile phone network dataset for one metropolitan area.
SMEs’ International Strategic Groups and Top Managers’ Psychological Characteristics
Authors: Cabral Ângelo , Carvalho Fernando , Ferreira José
Published: November 2020

This research analyzed the small and medium-sized enterprises’ (SMEs) international strategies concerning the scale and scope of the international activities. The major purpose was to study the international top managers’ psychological characteristics as distinctive capabilities within the defined international strategic groups. The international top managers’ cultural intelligence and emotional intelligence were taken as main characteristics to act in the international business environment. Therefore, we took as the main motivation to perform the present investigation the need to understand which psychological characteristics may help the international top managers to pursue high degrees of internationalization in their firms. This study was conducted in Portugal, and the sample was composed of 307 Portuguese SMEs’ international top managers directly responsible for the firms’ international decisions. The multinomial logistic regression method was used to test the hypotheses. The firms were classified into three international strategic groups based on the internationalization scale and scope. The degree of internationalization reflects that combination, creating groups with a high, medium, and low international exposure. The main result indicates as a distinctive capability, the international top managers’ cultural intelligence within the firms that exhibit a high international strategic positioning. Regarding the main contributions, this article contributes to the bodies of knowledge of international SMEs, cultural intelligence, emotional intelligence, and networking. This study also contributes to upper echelons theory and the resource-based view.
A Test Platform to Assess the Impact of Miniaturized Propulsion Systems
Authors: Stesina Fabrizio , Corpino Sabrina , Calvi Daniele
Published: November 2020

Miniaturized propulsion systems can enable many future CubeSats missions. The advancement of the Technology Readiness Level of this technology passes through the integration in a CubeSat platform and the assessment of the impact and the interactions of the propulsion systems on the actual CubeSat technology and vice versa. The request of power, the thermal environmental, and the electromagnetic emissions generated inside the platform require careful analyses. This paper presents the upgraded design and the validation of a CubeSat test platform (CTP) that can interface a wide range of new miniaturized propulsion systems and gather unprecedented information for these analyses, which can be fused with the commonly used ground support equipment. The CTP features are reported, and the main achievements of the tests are shown, demonstrating the effective capabilities of the platform and how it allows for the investigation of the mutual interactions at system level between propulsion systems and the CubeSat technology.
Impacts of the Winter Pea Crop (Instead of Rapeseed) on Soil Microbial Communities, Nitrogen Balance and Wheat Yield
Authors: Rezgui Cyrine , Riah-Anglet Wassila , Benoit Marie , Bernard Pierre Yves , Laval Karine , Trinsoutrot-Gattin Isabelle
Published: November 2020

Due to legume-based systems improving several aspects of soil fertility, the diversification of agrosystems using legumes in crop succession is gaining increasing interest. The benefits of legumes aroused the interest of farmers in the association of the Economic and Environmental Interest Group (EEIG), who introduced the idea of using the winter pea instead of rapeseed in their crop succession. The aim of this study is to evaluate the effects of the winter pea compared to those of rapeseed, as a head crop of the rotation, on soil microbial communities, enzyme activities, nitrogen (N) balance and yields. The field experiment involved two farmer plots that were selected within the EEIG. In each plot, two crop successions, including winter pea–wheat and rapeseed–wheat with fertilized and unfertilized strips, were examined for two years. Three times a year, under the wheat crop, composite soil samples were collected at depths of 0–20 cm, for microbial abundance and enzyme activity analyses, and twice a year at a depth of 0–60 cm, for the measuring of the mineral N. The results showed that the rapeseed–wheat succession maintained or enhanced soil bacterial and fungal biomasses and their enzyme activities. The winter pea–wheat succession enriched the soil’s mineral N content more consistently than the rapeseed–wheat succession. The mineral N enhancement’s effect was maintained under the wheat crop. Overall, the impact of the winter pea was positive on the soil’s N dynamics, but wheat yields were equivalent regardless of the previous crop (winter pea or rapeseed with and without fertilization). In the Normandy region, as rapeseed requires a large amount of N fertilizer and pesticide to maintain the yield and quality of crop products, it is suitable to favor the introduction of the winter pea as the head crop of the rotation, which indirectly allows for a reduction in the costs of input production and use, the working time of farmers and environmental pollution.
Drivers of Mechanization in Cotton Production in Benin, West Africa
Authors: Saliou Idelphonse O. , Zannou Afio , Aoudji Augustin K. N. , Honlonkou Albert N.
Published: November 2020

In the context of Africa’s farm labor scarcity, the use of mechanization is crucial for agricultural development. In Benin, technological advances, such as animal traction and motorization, are struggling to achieve the success expected by producers. The objective of this research was to analyze the drivers of mechanization in cotton production in Benin. Data collected from 482 cotton producers in three agroecological zones of the country were analyzed using a multinomial Logit model. The results revealed that 34% of cotton producers used hand tools, compared to 31% using draught animals and 35% using tractors. Variables such as education level, area cropped, access to land, access to credit and agroecological zone had a positive influence on the probability of using mechanization in the cotton production. Family labor size per household had a negative influence on the probability of using farm mechanization. Women were more likely to use farm mechanization than men. This research suggests that mechanization policies should adapt agricultural equipment to the specificities of the production systems of each agroecological zone, and strengthen land tenure security and access to credit, particularly for women cotton producers.
Native Perennial Plants Colonizing Abandoned Arable Fields in a Desert Area: Population Structure and Community Assembly
Authors: Al-Rowaily Saud L. , Al-Dosari Dekhil H. , Assaeed Abdulaziz M. , Abd-ElGawad Ahmed M. , El-Sheikh Mohamed A. , El-Bana Magdy I. , Al-Taisan Wafa’a A.
Published: November 2020

In recent years, the phenomenon of abandonment of arable fields has increased in Saudi Arabia due to low soil fertility, drought, low rainfall, high levels of evapotranspiration, soil salinization, and low level of groundwater. We evaluated the effect of agricultural land abandonment on soil properties, perennial vegetation composition, and population structure in the Al-Kharj region, Saudi Arabia. A total of 11 perennial plant species belonging to 9 families and 11 genera were detected in the different abandoned fields of the study area. Four plant communities were identified after the application of the detrended correspondence analysis (DCA) ordination. The indicator species were (1) Seidlitzia rosmarinus—Zygophyllum hamiense, (2) Traganum nudatum—Seidlitzia rosmarinus, (3) Traganum nudatum—Prosopis farcta, and (4) Calligonum comosum—Pulicaria undulata. Results of the soil analysis showed significant differences in soil texture, pH, salinity, and nutrient content among the four recognized plant communities. Demographic analysis indicated that populations of Zygophyllum hamiense and Calligonum comosum tended to be either inverse J-shaped or positively skewed which may have indicated rapidly-growing populations with high reproductive capacity. Conversely, the size–frequency distribution of Traganum nudatum, S. Rosmarinus, and Prosopis farcta was approximately symmetrical (i.e., bell-shaped). The present study sheds light on the necessity of managing abandoned agricultural fields for restoring and improving rangelands with native species that are adapted to the local conditions such as low water demand.
Silage of Intercropping Corn, Palisade Grass, and Pigeon Pea Increases Protein Content and Reduces In Vitro Methane Production
Authors: Ligoski Beatriz , Gonçalves Lucas Ferreira , Claudio Flavio Lopes , Alves Estenio Moreira , Krüger Ana Maria , Bizzuti Beatriz Elisa , Lima Paulo de Mello Tavares , Abdalla Adibe Luiz , Paim Tiago do Prado
Published: November 2020

Legume–grass intercropping systems are a sustainable option to improve nutritional quality of animal feed and decrease livestock greenhouse gas emissions. Thus, the present study evaluated yield, chemical composition and in vitro gas production of silages produced with intercropped palisade grass (Urochloa brizantha.(A.Rich.) R.D.Webster), pigeon pea (Cajanus cajan cv. Super N) and corn (Zea mays. L.). Forage was harvested and placed inside micro-silos, which were opened after 100 days and samples were collected for chemical composition and in vitro gas production analyses. Intercropped silage had higher crude protein, acid detergent fiber, and lignin content than corn silage. Moreover, intercropped silage decreased total gas and methane production. Therefore, intercropped silage showed potential to increase conserved feed nutritional quality and reduce methane emissions in livestock production systems.
Spatial and Temporal Variability of Soil Redox Potential, pH and Electrical Conductivity across a Toposequence in the Savanna of West Africa
Authors: Tano Bernard F. , Brou Casimir Y. , Dossou-Yovo Elliott R. , Saito Kazuki , Futakuchi Koichi , Wopereis Marco. C. S. , Husson Olivier
Published: November 2020

Soil redox potential is an important factor affecting soil functioning. Yet, very few agronomy studies included soil redox potential in relation to soil processes. The objective of this study was to evaluate the spatial and temporal variation in soil redox potential and to determine the soil parameters affecting its variation. Soil redox potential, soil moisture, soil temperature, pH and bulk electrical conductivity were measured in upland rice fields during two growing seasons at six positions along an upland–lowland continuum, including two positions at the upland, two at the fringe and two at the lowlands in central Côte d’Ivoire (West Africa). The measurements were made at the following soil depths: 3, 8, 20 and 35 cm. Soil redox potential varied between 500 and 700 mV at the upland positions, 400 and 700 mV at the fringe positions and 100 and 750 mV at the lowland positions, and increased with soil depth. Variations in soil redox potential were driven by soil moisture, bulk electrical conductivity and soil organic carbon. We concluded that for proper interpretation of soil redox potential, sampling protocols should systematically include soil pH, moisture and bulk electrical conductivity measurements.
Morphology, Phenology, Yield, and Quality of Durum Wheat Cultivated within Organic Olive Orchards of the Mediterranean Area
Authors: Panozzo Anna , Huang Hsinya , Bernazeau Bruno , Vamerali Teofilo , Samson Marie Françoise , Desclaux Dominique
Published: November 2020

In the current context of climate change, tree–crop combinations in agroforestry systems are suggested to mitigate water and heat stresses, particularly in semi-arid environments of the Mediterranean area. In this framework, a 3-year trial was conducted at the French National Research Institute for Agriculture, Food and the Environment (INRAE) in Mauguio (Southern France) in order to investigate the response of twenty-five durum wheat genotypes under a yearly pruned (AF) and a never-pruned alley olive orchard (AF+), in comparison with an open field without trees (control, C). The grain yield of wheat was markedly reduced in both the agroforestry systems AF (average −43%) and AF+ (−83%), according to the shading level. Among the yield components, the plant density at harvest was enhanced in AF (+22%) and AF+ (+3%), although with a significant reduction in the number of grains per spike (−37% in AF and −62% in AF+), and the number of spikes per plant (−32% in AF and −52% in AF+). The thousand-grain weight (TGW) and harvest index (HI) were slightly higher under moderate shade (AF; +12% vs. C) and severe shading (AF+; +6%). Plant biomass and spike size were significantly reduced in both agroforestry systems, while the flag leaf–spike distance (last internode) increased in AF. It was concluded that the moderate shading conditions of AF may create a sustainable agricultural system, and the wide intraspecific variability suggested a large scope for screening suitable genotypes, helping to produce ideotypes to implement agroforestry-oriented breeding programs.
Siliceous Natural Nanomaterials as Biorationals—Plant Protectants and Plant Health Strengtheners
Authors: Constantinescu-Aruxandei Diana , Lupu Carmen , Oancea Florin
Published: November 2020

This review aims to evaluate the scientific evidences for siliceous natural nanomaterials (SNNMs), natural zeolites, and diatomaceous earth, as biorationals. Both SNNMs are multifaceted agricultural inputs—plant protectants, plant biostimulants/plant strengtheners, soil improvers. The effects depend on the plant parts, where such siliceous natural nanomaterials (SNNMs) are applied. For stored grains, SNNMs act as plant protectants. Foliar applied SNNMs protect plants against biotic and abiotic stress—plant protectant and plant strengtheners. When applied to soil/roots, SNNMs stimulate root development and improve soil characteristics. These effects are related to the composition and porous (nano)structure of SNNMs. The large active siliceous surfaces of SNNMs are involved in: desiccation of the insects damaging stored grains, fungistatic effects against mycotoxigenic fungi and adsorption of their mycotoxins, desiccation of foliar pathogens and pests, stimulation of photosynthesis, release of soluble silicon species, improved soil characteristics. Similar to other biorationals from the category of basic substances with low risk, the SNNMs efficacy as plant protectants and plant health strengtheners is rather low. Complementary active ingredients should be used to enhance the effects of SNNMs on treated plants. For SNNMs applied as protectants of stored seeds, such strategy, of using complementary biorationals/low risk substances, proved to be highly effective.
Transcript Profile in Vegetable Soybean Roots Reveals Potential Gene Patterns Regulating K Uptake Efficiency
Authors: Liu Changkai , Tu Bingjie , Wang Xue , Li Yansheng , Zhang Qiuying , Liu Xiaobing
Published: November 2020

Significant differences have been reported in root K+ uptake between high potassium efficiency (HKE) and low potassium efficiency (LKE) in vegetable soybean genotypes. The ideal morphological and physiological characteristics of HKE have been defined. However, the mechanism by which HKE vegetable soybean genotypes efficiently uptake K remains unclear. By using representative materials, this study investigated the responses of root development to low K (LK) stress, and identified and assessed the key genes affecting high-efficiency K uptake between HKE and LKE vegetable soybean roots. The root growth of LKE was significantly inhibited under the LK condition. Compared with LKE, HKE had more lateral roots in both LK and CK (control) conditions. Lateral root of HKE was more preferentially responsive to exogenous IAA, with a wider response threshold to IAA concentration (from 0.1 to 1 µM). Transcriptome analysis revealed that LK induced transport-related genes up-regulated in HKE compared with LKE. In HKE, homologous genes of a K channel encoding gene potassium channel AKT1 (AKT1) and a K transporter gene high-affinity K+ transporter 5 (HAK5) were both highly expressed under the LK stress. Additionally, genes related to plant hormones signal transductions were also identified differentially expressed between the two genotypes. Plant hormone signaling involved in root morphological regulation pathways may play significant roles in improving the efficiency of vegetable soybean K+ uptake. A diagram showing possible molecular mechanisms in regulating root high-efficiency uptake K+ in vegetable soybean is proposed.
The Expression of ELF4-Like Genes Is Influenced by Light Quality in Petunia
Authors: Fukuda Naoya , Suenaga Tomohiro , Miura Erika , Tsukamoto Atsuko , Olsen Jorunn E.
Published: November 2020

The signals from photoreceptors modify plant morphogenesis and regulate the timing of flowering. In the long-day plant petunia, flowering is accelerated under blue (B) and white (W) light compared to red (R) light. In Arabidopsis thaliana L., ELF genes are involved in circadian clock-associated regulation of flowering under different light conditions. In this study, we aimed to assess the involvement of ELF genes in control of flowering by light quality in petunia. Two ELF4-like genes, PhELF4-1 and PhELF4-2 with 76% and 70% similarity to orthologues in pepper but low overall similarity to ELF genes in A. thaliana L., were characterized in petunia and their expression patterns studied under different light qualities. Both genes showed a rhythmic expression pattern and higher expression under B light from light emitting diodes (LED) and W light from fluorescent lamps than under R LED light from LED. For both genes, the expression peaked towards the end of the day, 12 h after start of a 14 h photoperiod. Compared with PhELF4-2, PhELF4-1 expression showed higher amplitude with significantly higher peak expression. As investigated for PhELF4-1, such an expression rhythm was kept for two days after transfer of the plants to continuous lighting using B LED, indicating a circadian rhythm. PhELF4-1 also responded with a phase shift after transfer to short days of an 8 h photoperiod. These results indicate that PhELF4-like genes in petunia are under photoperiodic control involving a circadian clock and play a role in signal transduction from one or more B light photoreceptors.
Improved Growth and Yield Response of Jew’s Mallow (Corchorus olitorius L.) Plants through Biofertilization under Semi-Arid Climate Conditions in Egypt
Authors: Yousef Ahmed Fathy , Youssef Mohamed Ahmed , Ali Muhammad Moaaz , Ibrahim Muhammed Mustapha , Xu Yong , Mauro Rosario Paolo
Published: November 2020

This study was conducted to comparatively assess the effects of fertilization typology (organic, inorganic, and biofertilization) on the growth, yield, and compositional profile of Jew’s mallow. The experiment was carried out over two growing seasons, under semi-arid climate conditions on silty loam soil. We adopted three fertilization strategies: (1) inorganic NPK fertilizer (146, 74, and 57 kg ha−1 for N, P2O5, and K2O, respectively), (2) farmyard manure (36 m3 ha−1), and (3) a biofertilizer (a set of mixed cultures of Bacillus spp., Candida spp., and Trichoderma spp. at 36 L ha−1). Treatment combinations were control (without fertilization, T1), NPK fertilizer (T2), farmyard manure (FYM, T3), biofertilizer (T4), NPK+biofertilizer (T5), and FYM+biofertilizer (T6). The T5 treatment maximized both plant and leaf biomass (up to 31.6 and 8.0 t ha−1, respectively), plant height (68.5 cm), leaf area (370 cm m−2), leaf protein content (18.7%), as well as N, P, and K concentration in leaves (2.99, 0.88, and 2.01 mg 100 g−1, respectively). The leaves’ weight incidence was lower in T5 treatment (36.7%) as compared to the unfertilized plants (T1). The results revealed that the combined application of inorganic NPK plus biofertilizer is most beneficial to increase growth, yield, and nutrient accumulation in Jew’s mallow plants.
Healthcare Challenges and Future Solutions in Dental Practice: Assessing Oral Antibiotic Resistances by Contemporary Point-Of-Care Approaches
Authors: Belibasakis Georgios N. , Lund Bodil K. , Krüger Weiner Carina , Johannsen Benita , Baumgartner Desirée , Manoil Daniel , Hultin Margareta , Mitsakakis Konstantinos
Published: November 2020

Antibiotic resistance poses a global threat, which is being acknowledged at several levels, including research, clinical implementation, regulation, as well as by the World Health Organization. In the field of oral health, however, the issue of antibiotic resistances, as well as of accurate diagnosis, is underrepresented. Oral diseases in general were ranked third in terms of expenditures among the EU-28 member states in 2015. Yet, the diagnosis and patient management of oral infections, in particular, still depend primarily on empiric means. On the contrary, on the global scale, the field of medical infections has more readily adopted the integration of molecular-based systems in the diagnostic, patient management, and antibiotic stewardship workflows. In this perspective review, we emphasize the clinical significance of supporting in the future antibiotic resistance screening in dental practice with novel integrated and point-of-care operating tools that can greatly support the rapid, accurate, and efficient administration of oral antibiotics.
Antimicrobial Activity of Bee-Collected Pollen and Beebread: State of the Art and Future Perspectives
Authors: Didaras Nikos Asoutis , Karatasou Katerina , Dimitriou Tilemachos G , Amoutzias Grigoris D. , Mossialos Dimitris
Published: November 2020

Bee-collected pollen (BCP) is a well-known functional food. Honey bees process the collected pollen and store it in the hive, inside the comb cells. The processed pollen is called bee- bread or ambrosia and it is the main source of proteins, lipids, vitamins, macro-and micro-elements in honey bee nutrition. During storage, beebread undergoes solid state fermentation which preserves it and increases the bioavailability of nutrients. Research on beebread has been rather limited until now. In recent years, there is an increasing interest regarding the antimicrobial properties of BCP and beebread, due to emerging antimicrobial resistance by pathogens. Both BCP and beebread exhibit antimicrobial properties against diverse pathogens, like bacteria and fungi. As is the case with other bee products, lack of antimicrobial resistance might be attributed to the synergy of more than one antimicrobial compounds within BCP and beebread. Furthermore, BCP and bee bread exert targeted activity against pathogens and affect the host microbiome in a prebiotic manner. This review aims to present up to date research findings regarding these aspects as well as to discuss current challenges and future perspectives in the field.
The Pivotal Role of Adipocyte-Na K peptide in Reversing Systemic Inflammation in Obesity and COVID-19 in the Development of Heart Failure
Authors: Xie Zi-jian , Novograd Joel , Itzkowitz Yaakov , Sher Ariel , Buchen Yosef D. , Sodhi Komal , Abraham Nader G. , Shapiro Joseph I.
Published: November 2020

This review summarizes data from several laboratories that have demonstrated a role of the Na/K-ATPase, specifically its α1 subunit, in the generation of reactive oxygen species (ROS) via the negative regulator of Src. Together with Src and other signaling proteins, the Na/K-ATPase forms an oxidant amplification loop (NKAL), amplifies ROS, and participates in cytokines storm in obesity. The development of a peptide fragment of the α1 subunit, NaKtide, has been shown to negatively regulate Src. Several groups showed that the systemic administration of the cell permeable modification of NaKtide (pNaKtide) or its selective delivery to fat tissue—adipocyte specific expression of NaKtide—ameliorate the systemic elevation of inflammatory cytokines seen in chronic obesity. Severe acute respiratory syndrome – coronavirus 2 (SARS-CoV-2), the RNA Coronavirus responsible for the COVID-19 global pandemic, invades cells via the angiotensin converting enzyme 2 (ACE-2) receptor (ACE2R) that is appended in inflamed fat tissue and exacerbates the formation of the cytokines storm. Both obesity and heart and renal failure are well known risks for adverse outcomes in patients infected with COVID-19. White adipocytes express ACE-2 receptors in high concentration, especially in obese patients. Once the virus invades the white adipocyte cell, it creates a COVID19–porphyrin complex which degrades and produces free porphyrin and iron and increases ROS. The increased formation of ROS and activation of the NKAL results in a further potentiated formation of ROS production, and ultimately, adipocyte generation of more inflammatory mediators, leading to systemic cytokines storm and heart failure. Moreover, chronic obesity also results in the reduction of antioxidant genes such as heme oxygenase-1 (HO-1), increasing adipocyte susceptibility to ROS and cytokines. It is the systemic inflammation and cytokine storm which is responsible for many of the adverse outcomes seen with COVID-19 infections in obese subjects, leading to heart failure and death. This review will also describe the potential antioxidant drugs and role of NaKtide and their demonstrated antioxidant effect used as a major strategy for improving obesity and epicardial fat mediated heart failure in the context of the COVID pandemic.
Effects of Allicin on Pathophysiological Mechanisms during the Progression of Nephropathy Associated to Diabetes
Authors: Arellano-Buendía Abraham Said , Castañeda-Lara Luis Gerardo , Loredo-Mendoza María L. , García-Arroyo Fernando E. , Rojas-Morales Pedro , Argüello-García Raúl , Juárez-Rojas Juan G. , Tapia Edilia , Pedraza-Chaverri José , Sánchez-Lozada Laura Gabriela , Osorio-Alonso Horacio
Published: November 2020

This study aimed to assess the impact of allicin on the course of diabetic nephropathy. Study groups included control, diabetes, and diabetes-treated rats. Allicin treatment (16 mg/kg day/p.o.) started after 1 month of diabetes onset and was administered for 30 days. In the diabetes group, the systolic blood pressure (SBP) increased, also, the oxidative stress and hypoxia in the kidney cortex were evidenced by alterations in the total antioxidant capacity as well as the expression of nuclear factor (erythroid-derived 2)-like 2/Kelch ECH associating protein 1 (Nrf2/Keap1), hypoxia-inducible factor 1-alpha (HIF-1α), vascular endothelial growth factor (VEGF), erythropoietin (Epo) and its receptor (Epo-R). Moreover, diabetes increased nephrin, and kidney injury molecule-1 (KIM-1) expression that correlated with mesangial matrix, the fibrosis index and with the expression of connective tissue growth factor (CTGF), transforming growth factor-β1 (TGF-β1), and α-smooth muscle actin (α-SMA). The insulin levels and glucose transporter protein type-4 (GLUT4) expression were decreased; otherwise, insulin receptor substrates 1 and 2 (IRS-1 and IRS-2) expression was increased. Allicin increased Nrf2 expression and decreased SBP, Keap1, HIF-1α, and VEGF expression. Concurrently, nephrin, KIM-1, the mesangial matrix, fibrosis index, and the fibrotic proteins were decreased. Additionally, allicin decreased hyperglycemia, improved insulin levels, and prevented changes in (GLUT4) and IRSs expression induced by diabetes. In conclusion, our results demonstrate that allicin has the potential to help in the treatment of diabetic nephropathy. The cellular mechanisms underlying its effects mainly rely on the regulation of antioxidant, antifibrotic, and antidiabetic mechanisms, which can contribute towards delay in the progression of renal disease.
Effects of Working Fluids on the Performance of a Roots Pump for Hydrogen Recirculation in a PEM Fuel Cell System
Authors: Feng Jianmei , Xing Linfen , Wang Bingqi , Wei Huan , Xing Ziyi
Published: November 2020

In this paper, the performance of a Roots pump for hydrogen recirculation in proton exchange membrane (PEM) fuel cell system is simulated based on CFD modeling. The Roots pump is in a three-lobe configuration with helical rotors, and it is developed specifically for fuel cell systems between 60 to 110 kW. A three-dimensional model of the Roots pump is established to predict the pump performance, including the flow rate and power consumption under various operating conditions. Extensive simulations were conducted and then verified experimentally by operating with working fluids of air and helium. Based on the validated CFD model, the contents of water vapor and nitrogen in the hydrogen recirculated are taken into account to evaluate the Roots pump performance numerically according to the actual conditions of the recirculating hydrogen at the stack outlet. It is shown that the volumetric efficiency and isentropic efficiency are improved with the increase fraction of water vapor and nitrogen. It is found that the performance of the Roots pump integrated in the PEM fuel cell system is between the performance of the pump working with air and helium. Finally, correlations of volumetric efficiency and isentropic efficiency are given based on the CFD results to show the general pattern of this kind of hydrogen pump. It is believed that these equations are very helpful to the design and operation control of the PEM fuel cell system.
Steering Pull Model and Its Sensitivity Analysis
Authors: Kim Seong Han , Shin Min Chul
Published: November 2020

When a vehicle goes on the straight road with a bank angle, a steering pull makes the driver exert a constant steering torque to the steering wheel, which causes an annoying steering feel to the driver. This paper proposes a steering pull model and sensitivity analysis on the steering pull. In order to develop the steering pull model, pulling forces on the tires, such as plysteer and conicity forces, lateral force due to slip angle, lifting forces due to cast and kingpin, and camber force are modeled. A steering system is also modeled because the generated pulling forces are attenuated as it is transmitted through the steering system. Each component of the steering system, such as lower body linkages, rack and pinion gear, universal joint, and steering column with electric power steering (EPS) system is modeled, and then they are integrated into a complete steering system. Finally, the steering pull model is developed by integrating the pulling force model with the steering system model. For verification, the steering pull of a vehicle is estimated based on the model, and the results are compared with the experimental results. For the verification experiments, a steering pull measurement system using a global positioning system (GPS) and its accessories are used. The result comparison showed that the developed steering pull model provides very accurate estimation results. Based on the steering pull model, the sensitivity of steering pull factors, such as caster angle, kingpin angle, camber angle, rack friction force, and anti-rattle spring (ARS) stiffness is analyzed.
Algorithm for Generating 3D Geometric Representation Based on Indoor Point Cloud Data
Authors: Ryu Min Woo , Oh Sang Min , Kim Min Ju , Cho Hun Hee , Son Chang Baek , Kim Tae Hoon
Published: November 2020

This study proposes a new method to generate a three-dimensional (3D) geometric representation of an indoor environment by refining and processing an indoor point cloud data (PCD) captured through backpack laser scanners. The proposed algorithm comprises two parts to generate the 3D geometric representation: data refinement and data processing. In the refinement section, the inputted indoor PCD are roughly segmented by applying random sample consensus (RANSAC) to raw data based on an estimated normal vector. Next, the 3D geometric representation is generated by calculating and separating tangent points on segmented PCD. This study proposes a robust algorithm that utilizes the topological feature of the indoor PCD created by a hierarchical data process. The algorithm minimizes the size and the uncertainty of raw PCD caused by the absence of a global navigation satellite system and equipment errors. The result of this study shows that the indoor environment can be converted into 3D geometric representation by applying the proposed algorithm to the indoor PCD.
Assessing Postural Stability Using Coupling Strengths between Center of Pressure and Its Ground Reaction Force Components
Authors: Sung Jia-Li , Guo Lan-Yuen , Liu Chin-Hsuan , Lee Posen , Yen Chen-Wen , Liaw Lih-Jiun
Published: November 2020

The center of pressure (COP), which is defined as the point at which the resultant ground reaction force (GRF) is applied on a body, provides valuable information for postural stability assessment. This is because the fundamental goal of balance control is to regulate the center of mass (COM) of the human body by adaptively changing the position of the COP. By using Newtonian mechanics to develop two equations that relate the two-dimensional COP coordinates to the GRF components, one can easily determine the location of the COP using a force plate. An important property of these two equations is that for a given COP position, there exists an infinite number of GRF component combinations that can satisfy these two equations. However, the manner in which a postural control system deals with such redundancy is still unclear. To address this redundancy problem, we introduce four postural stability features by quantifying the coupling strengths between the COP coordinates and their GRF components. Experiments involving younger (18–24 years old) and older (65–73 years) participants were conducted. The efficacy of the proposed features was demonstrated by comparing the differences between variants of each feature for each age group (18–24 and 65–73 years). The results demonstrated that the coupling strengths between the anterior–posterior (AP) direction coordinate of the COP and its GRF components for the older group were significantly higher than those of the younger group. These experimental results suggest that (1) the balance control system of the older group is more constrained than that of the younger group in coordinating the GRF components and (2) the proposed features are more sensitive to age variations than one of the most reliable and accurate conventional COP features. The best testing classification accuracy achieved by the proposed features was 0.883, whereas the testing classification accuracy achieved by the most accurate conventional COP feature was 0.777. Finally, by investigating the interactions between the COP and its GRF components using the proposed features, we found that that the AP component of the GRF of younger people plays a more active role in balance control than that of the GRF of older people. Based on these findings, it is believed that the proposed features can be used as a set of stability measures to assess the effects on posture stability from various health-related conditions such as aging and fall risk.
Special Issue on Unmanned Aerial Vehicles (UAVs)
Authors: Jung Sunghun
Published: November 2020

This editorial paper was a special issue of Applied Sciences belonging to the section of mechanical engineering in MDPI journal and summarized the collected manuscripts regarding the unmanned aerial vehicles (UAVs) related technologies, including communication, control, collision avoidance, modeling, path planning, human-machine interface (HMI), artificial intelligence (AI), etc. Chronologically, this special issue was started to be coordinated at the end of Oct 2018, prepared for a month and opened to collect manuscripts from the middle of Nov 2018 until the end of Dec 2019. During almost a year, 26 papers were published online out of 50 submitted papers which results in 52% acceptance rate.
On the Effectiveness of Adversarial Training in Defending against Adversarial Example Attacks for Image Classification
Authors: Park Sanglee , So Jungmin
Published: November 2020

State-of-the-art neural network models are actively used in various fields, but it is well-known that they are vulnerable to adversarial example attacks. Throughout the efforts to make the models robust against adversarial example attacks, it has been found to be a very difficult task. While many defense approaches were shown to be not effective, adversarial training remains as one of the promising methods. In adversarial training, the training data are augmented by “adversarial” samples generated using an attack algorithm. If the attacker uses a similar attack algorithm to generate adversarial examples, the adversarially trained network can be quite robust to the attack. However, there are numerous ways of creating adversarial examples, and the defender does not know what algorithm the attacker may use. A natural question is: Can we use adversarial training to train a model robust to multiple types of attack? Previous work have shown that, when a network is trained with adversarial examples generated from multiple attack methods, the network is still vulnerable to white-box attacks where the attacker has complete access to the model parameters. In this paper, we study this question in the context of black-box attacks, which can be a more realistic assumption for practical applications. Experiments with the MNIST dataset show that adversarially training a network with an attack method helps defending against that particular attack method, but has limited effect for other attack methods. In addition, even if the defender trains a network with multiple types of adversarial examples and the attacker attacks with one of the methods, the network could lose accuracy to the attack if the attacker uses a different data augmentation strategy on the target network. These results show that it is very difficult to make a robust network using adversarial training, even for black-box settings where the attacker has restricted information on the target network.
Numerical Analysis of the Bottom Thickness of Closed Rectangular Tanks Used as Pontoons
Authors: Szymczak-Graczyk Anna
Published: November 2020

This paper concerns the numerical analysis of closed rectangular tanks made in one stage, used as pontoons. Such structures can be successfully used as floating platforms, although they primarily serve as floats for ‘houses on water’. Amphibious construction has fascinated designers for many years and is becoming, in addition to a great and prestigious location for many purposes, a practical global necessity. Severe weather phenomena that no country is safe from, i.e., heavy rains or floods, combined with the scarcity of space intended for the construction of residential buildings, encourage development at the contact of water and land or on water only. This paper contains an analysis of the static work of tanks with different bottom thickness subjected to hydrostatic load acting on tank walls and the bottom plate and evenly distributed load acting on the upper plate, i.e., major impacts that occur when tanks are used as pontoons. Calculations were made using the finite difference method in terms of energy, assuming the Poisson’s ratio ν = 0. Based on the solutions obtained, charts were made that illustrated the change in bending moments at the characteristic points of the analysed tanks depending on acting loads. The article also includes calculations of buoyancy, stability and the metacentric height for tanks with different bottom thicknesses, with the main purpose being to improve and share knowledge on their safe use as pontoons.
Characterization and Optimal Design of Silicon-Rich Nitride Nonlinear Waveguides for 2 μm Wavelength Band
Authors: Tu Zhihua , Chen Daru , Hu Hao , Gao Shiming , Guan Xiaowei
Published: November 2020

Optical communication using the 2 μm wavelength band is attracting growing attention for the sake of mitigating the information ‘capacity crunch’ on the way, where on-chip nonlinear waveguides can play vital roles. Here, silicon-rich nitride (SRN) ridge waveguides with different widths and rib heights are fabricated and measured. Linear characterizations show a loss of ~2 dB/cm of the SRN ridge waveguides and four-wave mixing (FWM) experiments with a continuous wave (CW) pump reveal a nonlinear refractive index of ~1.13 × 10−18 m2/W of the SRN material around the wavelength 1950 nm. With the extracted parameters, dimensions of the SRN ridge waveguides are optimally designed for improved nonlinear performances for the 2 μm band, i.e., a maximal nonlinear figure of merit (i.e., the ratio of nonlinearity to loss) of 0.0804 W−1 or a super-broad FWM bandwidth of 518 nm. Our results and design method open up new possibilities for achieving high-performance on-chip nonlinear waveguides for long-wavelength optical communications.
Efficient Hogel-Based Hologram Synthesis Method for Holographic Stereogram Printing
Authors: Dashdavaa Erkhembaatar , Khuderchuluun Anar , Wu Hui-Ying , Lim Young-Tae , Shin Chang-Won , Kang Hoonjong , Jeon Seok-Hee , Kim Nam
Published: November 2020

With the development of the holographic printer, printing synthetic hologram requires smaller holographic element (hogel) size to improve spatial resolution of the reconstruction. On the contrary, a larger hogel size affords higher angular resolution, but it leads to a lower lateral resolution and there exists a trade-off problem. In this paper, a hologram synthesis method based on three-dimensional (3D) rendering of computer-generated holographic stereogram (HS) is proposed to limit the spatial-angular trade-off problem. The perspectives of the 3D scene are captured by re-centering the camera method and transformed into parallax-related images by a proposed pixel re-arrangement algorithm for holographic printing. Unlike the conventional approaches, the proposed algorithm not only improves the angular resolution of the reconstruction while maintaining the hogel size fixed, but also keeps the spatial resolution without degradation. The effectiveness of the proposed method is verified by numerical simulation and an optical experiment.
Analysis of Influencing Mechanism of Subgrade Frost Heave on Vehicle-Track Dynamic System
Authors: Gao Liang , Zhao Wenqiang , Hou Bowen , Zhong Yanglong
Published: November 2020

Uneven subgrade frost heave has been a severe problem for the operation of high-speed railways in cold regions. In order to reveal the influencing mechanism of frost heave on the vehicle-track system, a novel FEM (finite element method) model based on an explicit algorithm was proposed. In the novel model, the existence of the leverage effect in slab track, which was caused by frost heave, was realistically reproduced at first, and then the vehicle model started running for evaluating the influence of the frost heave on the whole dynamic system. Results show that the leverage effect plays a key role in analyzing the influence of frost heave on the vehicle-track system, besides for track irregularity and contact loss. Specifically, the leverage effect decreases the stability of the slab track and causes an increase in dynamic irregularity. The roles of the track irregularity and the contact loss in the influencing mechanism were also revealed. With the ratio of wavelength to amplitude increasing, the track irregularity is gradually dominant in the influence mechanism of frost heave on the vehicle-track system. The research could provide a reference for the management and maintenance of the slab track in cold regions.