bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation on the Residual Stresses and Fatigue Performance of Riveted Single Strap Butt Joints
Authors: Liu Jintong , Zhao Anan , Ke Zhenzheng , Li Zhiqiang , Bi Yunbo
Published: August 2020

In aircraft manufacturing, riveting is one of the most important connection ways to fasten the sheet metal parts. The riveted single strap butt joints are mainly used in the load-bearing components of the aircraft such as the fuselage and wing panels. The connection quality and fatigue performance of the riveted joints directly affect the reliability and safety of the aircraft. In this paper, under the assumption of constant temperature, the fatigue strengthening mechanism of interference-fit riveting is introduced based on elastic-plastic mechanics and fracture mechanics. On this basis, the finite element (FE) models of the riveted single strap butt joints with various strap thickness and rivet sizes/arrangements are established. The residual stresses distribution around the riveted hole is analyzed. Furthermore, the fatigue tests of the riveted single strap butt joints with cyclic loading are carried out. The experimental results verified the correctness and effectiveness of the simulation model. Finally, the conclusion is drawn that increasing rivet size and strap thickness within the allowable weight range can improve the fatigue performance of the riveted single strap butt joints. The knowledge could be used to guide the structural design and optimization of the riveted butt joints against fatigue.
Low-Temperature Biosurfactants from Polar Microbes
Authors: Trudgeon Benjamin , Dieser Markus , Balasubramanian Narayanaganesh , Messmer Mitch , Foreman Christine M.
Published: August 2020

Surfactants, both synthetic and natural, are used in a wide range of industrial applications, including the degradation of petroleum hydrocarbons. Organisms from extreme environments are well-adapted to the harsh conditions and represent an exciting avenue of discovery of naturally occurring biosurfactants, yet microorganisms from cold environments have been largely overlooked for their biotechnological potential as biosurfactant producers. In this study, four cold-adapted bacterial isolates from Antarctica are investigated for their ability to produce biosurfactants. Here we report on the physical properties and chemical structure of biosurfactants from the genera Janthinobacterium, Psychrobacter, and Serratia. These organisms were able to grow on diesel, motor oil, and crude oil at 4 °C. Putative identification showed the presence of sophorolipids and rhamnolipids. Emulsion index test (E24) activity ranged from 36.4–66.7%. Oil displacement tests were comparable to 0.1–1.0% sodium dodecyl sulfate (SDS) solutions. Data presented herein are the first report of organisms of the genus Janthinobacterium to produce biosurfactants and their metabolic capabilities to degrade diverse petroleum hydrocarbons. The organisms’ ability to produce biosurfactants and grow on different hydrocarbons as their sole carbon and energy source at low temperatures (4 °C) makes them suitable candidates for the exploration of hydrocarbon bioremediation in low-temperature environments.
Characterization of Single Gene Deletion Mutants Affecting Alternative Oxidase Production in Neurospora crassa: Role of the yvh1 Gene
Authors: Desaulniers Adrien Beau , Kishore Nishka , Adames Kelly , Nargang Frank E.
Published: August 2020

The Neurospora crassa AOD1 protein is a mitochondrial alternative oxidase that passes electrons directly from ubiquinol to oxygen. The enzyme is encoded by the nuclear aod-1 gene and is produced when the standard electron transport chain is inhibited. We previously identified eleven strains in the N. crassa single gene deletion library that were severely deficient in their ability to produce AOD1 when grown in the presence of chloramphenicol, an inhibitor of mitochondrial translation that is known to induce the enzyme. Three mutants affected previously characterized genes. In this report we examined the remaining mutants and found that the deficiency of AOD1 was due to secondary mutations in all but two of the strains. One of the authentic mutants contained a deletion of the yvh1 gene and was found to have a deficiency of aod-1 transcripts. The YVH1 protein localized to the nucleus and a post mitochondrial pellet from the cytoplasm. A zinc binding domain in the protein was required for rescue of the AOD1 deficiency. In other organisms YVH1 is required for ribosome assembly and mutants have multiple phenotypes. Lack of YVH1 in N. crassa likely also affects ribosome assembly leading to phenotypes that include altered regulation of AOD1 production.
Chemometric Models of Differential Amino Acids at the Navα and Navβ Interface of Mammalian Sodium Channel Isoforms
Authors: Villa-Diaz Fernando , Lopez-Nunez Susana , Ruiz-Castelan Jordan E. , Salinas-Stefanon Eduardo Marcos , Scior Thomas
Published: August 2020

(1) Background: voltage-gated sodium channels (Navs) are integral membrane proteins that allow the sodium ion flux into the excitable cells and initiate the action potential. They comprise an α (Navα) subunit that forms the channel pore and are coupled to one or more auxiliary β (Navβ) subunits that modulate the gating to a variable extent. (2) Methods: after performing homology in silico modeling for all nine isoforms (Nav1.1α to Nav1.9α), the Navα and Navβ protein-protein interaction (PPI) was analyzed chemometrically based on the primary and secondary structures as well as topological or spatial mapping. (3) Results: our findings reveal a unique isoform-specific correspondence between certain segments of the extracellular loops of the Navα subunits. Precisely, loop S5 in domain I forms part of the PPI and assists Navβ1 or Navβ3 on all nine mammalian isoforms. The implied molecular movements resemble macroscopic springs, all of which explains published voltage sensor effects on sodium channel fast inactivation in gating. (4) Conclusions: currently, the specific functions exerted by the Navβ1 or Navβ3 subunits on the modulation of Navα gating remain unknown. Our work determined functional interaction in the extracellular domains on theoretical grounds and we propose a schematic model of the gating mechanism of fast channel sodium current inactivation by educated guessing.
Genoprotective Properties and Metabolites of β-Glucan-Rich Edible Mushrooms Following Their In Vitro Fermentation by Human Faecal Microbiota
Authors: Boulaka Athina , Christodoulou Paris , Vlassopoulou Marigoula , Koutrotsios Georgios , Bekiaris Georgios , Zervakis Georgios , Mitsou Evdokia , Saxami Georgia , Kyriacou Adamantini , Zervou Maria , Georgiadis Panagiotis , Pletsa Vasiliki
Published: August 2020

A variety of bioactive compounds, constituents of edible mushrooms, in particular β-glucans, i.e., a group of β-d-glucose polysaccharides abundant in the fungal cell walls, have been linked to immunomodulating, anticancer and prebiotic activities. The aim of the study was the investigation of the genoprotective effects of edible mushrooms produced by Pleurotus eryngii, Pleurotus ostreatus and Cyclocybe cylindracea (Basidiomycota). Mushrooms from selected strains of the species mentioned above were fermented in vitro using faecal inocula from healthy volunteers. The cytotoxic and anti-genotoxic properties of the fermentation supernatants (FSs) were investigated in Caco-2 human colon adenocarcinoma cells. The FSs were cytotoxic in a dose-dependent manner. Non-cytotoxic concentrations were used for the genotoxicity studies, which revealed that mushrooms’ FSs have the ability to protect Caco-2 cells against tert-butyl hydroperoxide (t-BOOH), a known genotoxic agent. Their global metabolic profiling was assessed by 1H-NMR spectroscopy. A total of 37 metabolites were identified with the use of two-dimensional (2D) homo- and hetero-nuclear NMR experiments. Multivariate data analysis monitored the metabolic variability of gut microbiota and probed to biomarkers potentially associated with the health-promoting effects of edible mushrooms.
Morphological, Material, and Optical Properties of ZnO/ZnS/CNTs Nanocomposites on SiO2 Substrate
Authors: Tsai Yu Sheng , Lin Xin Dai , Chan Wei Lun , Tsai Shang Che , Liao Wei Jen , Wu Yew Chung Sermon , Chen Hsiang
Published: August 2020

Ultraviolet A light (UV-A, 320–400 nm), which is unblockable by sunscreen, requires careful detection for disease avoidance. In this study, we propose a novel photosensing device capable of detecting UV-A. Cancer-causing UV light can be simultaneously monitored with tiny rapid response sensors for a high carrier transition speed. In our research, a multifunctional ZnO/ZnS nanomaterial hybrid-sprinkled carbon nanotube (CNT) was created for the purpose of fabricating a multipurpose, semiconductorbased application. For our research, ZnO nanorods (NRs) were grown by using a facile hydrothermal method on SiO2 substrate, then vulcanized to form ZnO/ZnS coreshell nanorods, which were sprinkled with carbon nanotubes (CNTs). Results indicate that SiO2/ZnO/ZnS/CNT structures exhibited a stronger conducting current with and without light than those samples without CNTs. Multiple material characterizations of the nanostructures, including of atomic force microscopy (AFM) surface morphology evaluation, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) indicate that CNTs could be successfully spread on top of the ZnO/ZnS coreshell structures. Furthermore, chemical binding properties, material crystallinity, and optical properties were examined by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), and photoluminescence (PL). Owing to their compact size, simple fabrication, and low cost, ZnO/ZnS coreshell NRs/CNT/SiO2-based nanocomposites are promising for future industrial optoelectronic applications.
Dual Amplified Spontaneous Emission and Lasing from Nanographene Films
Authors: Muñoz-Mármol Rafael , Bonal Víctor , Paternò Giuseppe M. , Ross Aaron M. , Boj Pedro G. , Villalvilla José M. , Quintana José A. , Scotognella Francesco , D’Andrea Cosimo , Sardar Samim , Lanzani Guglielmo , Gu Yanwei , Wu Jishan , Díaz-García María A.
Published: August 2020

Chemically synthesized zigzag-edged nanographenes (NG) have recently demonstrated great success as the active laser units in solution-processed organic distributed feedback (DFB) lasers. Here, we report the first observation of dual amplified spontaneous emission (ASE) from a large-size NG derivative (with 12 benzenoid rings) dispersed in a polystyrene film. ASE is observed simultaneously at the 685 and 739 nm wavelengths, which correspond to different transitions of the photoluminescence spectrum. Ultrafast pump-probe spectroscopy has been used to ascertain the underlying photophysical processes taking place in the films. DFB lasers, based on these materials and top-layer nanostructured polymeric resonators (i.e., one or two-dimensional surface relief gratings), have been fabricated and characterized. Lasers emitting close to either one of the two possible ASE wavelengths, or simultaneously at both of them, have been prepared by proper selection of the resonator parameters.
COVID-19 Lockdown and Changes of the Dietary Pattern and Physical Activity Habits in a Cohort of Patients with Type 2 Diabetes Mellitus
Authors: Ruiz-Roso María Belén , Knott-Torcal Carolina , Matilla-Escalante Diana C. , Garcimartín Alba , Sampedro-Nuñez Miguel A. , Dávalos Alberto , Marazuela Mónica
Published: August 2020

The COVID-19 lockdown clearly affected the lifestyle of the population and entailed changes in their daily habits, which involved potential health consequences, especially on patients with Type 2 Diabetes Mellitus (T2DM). We aimed to examine the impact of the lockdown caused by COVID-19 pandemic on both nutrition and exercise habits, as well as the psychological effects in patients with T2DM, compared to their usual diet and physical activity level previous to the complete home confinement. We also intended to analyse any potential variables that may have influenced these lifestyle modifications. A Food Frequency Questionnaire (FFQ), Physical Activity Questionnaire (IPAQ), Food Craving Questionnaire-State (FCQ-S) and Food Craving Questionnaire-Trait (FCQ-T) were used. Our results showed an increase in vegetable, sugary food and snack consumption. An association between levels of foods cravings and snack consumption was also found. Data also showed a high percentage of physical inactivity before the COVID-19 lockdown, which was exacerbated during the home confinement. These findings emphasise the great importance to do further research with larger study samples to analyse and explore dietary habits and to develop public health policies to promote a healthy lifestyle in terms of diet and physical activity in these patients, especially after this strict period of lockdown.
Relationship between Nutritional Status and Clinical and Biochemical Parameters in Hospitalized Patients with Heart Failure with Reduced Ejection Fraction, with 1-year Follow-Up
Authors: Kałużna-Oleksy Marta , Krysztofiak Helena , Migaj Jacek , Wleklik Marta , Dudek Magdalena , Uchmanowicz Izabella , Lesiak Maciej , Straburzyńska-Migaj Ewa
Published: August 2020

Heart Failure (HF) is a cardiovascular disease with continually increasing morbidity and high mortality. The purpose of this study was to analyze nutritional status in patients diagnosed with HF with reduced ejection fraction (HFrEF) and evaluate the impact of malnutrition on their prognosis. The Polish version of MNA form (Mini Nutritional Assessment) was used to assess the patients’ nutritional status. The New York Heart Association (NYHA) class, exacerbation of HF, chosen echocardiographic and biochemical parameters, e.g., natriuretic peptides or serum albumin, were also analyzed. Among the 120 consecutive patients, 47 (39%) had a normal nutritional status, 62 (52%) were at risk of malnutrition and 11 (9%) were malnourished. The patients with malnutrition more frequently presented with HF exacerbation in comparison to those with normal nutritional status (82% vs. 30% respectively, p = 0.004). There were no significant differences between the investigated groups as to natriuretic peptides; however, both the malnourished patients and those at risk of malnutrition tend to show higher B-type natriuretic peptide (BNP) and NT-proBNP concentrations. During the average 344 days of follow-up 19 patients died and 25 were hospitalized due to decompensated HF. Malnutrition or being at risk of malnutrition seems to be associated with both worse outcomes and clinical status in HFrEF patients.
Combining Computed Tomography and Histology Leads to an Evolutionary Concept of Hepatic Alveolar Echinococcosis
Authors: Grimm Johannes , Beck Annika , Nell Juliane , Schmidberger Julian , Hillenbrand Andreas , Beer Ambros J. , Dezsényi Balázs , Shi Rong , Beer Meinrad , Kern Peter , Henne-Bruns Doris , Kratzer Wolfgang , Moller Peter , Barth Thomas FE , Gruener Beate , Graeter Tilmann
Published: August 2020

Alveolar echinococcosis (AE) is caused by the intermediate stage of Echinococcus multilocularis. We aimed to correlate computed tomography (CT) data with histology to identify distinct characteristics for different lesion types. We classified 45 samples into five types with the Echinococcus multilocularis Ulm Classification for Computed Tomography (EMUC-CT). The various CT lesions exhibited significantly different histological parameters, which led us to propose a progression model. The initial lesion fit the CT type IV classification, which comprises a single necrotic area with the central located laminated layer, a larger distance between laminated layer and border zone, a small fibrotic peripheral zone, and few small particles of Echinococcus multilocularis (spems). Lesions could progress through CT types I, II, and III, characterized by shorter distances between laminated layer and border zone, more spems inside and surrounding the lesion, and a pronounced fibrotic rim (mostly in type III). Alternatively, lesions could converge to a highly calcified, regressive state (type V). Our results suggest that the CT types mark sequential stages of the infection, which progress over time. These distinct histological patterns advance the understanding of interactions between AE and human host; moreover, they might become prognostically and therapeutically relevant.
Effects of Formulation Excipients on Skin Barrier Function in Creams Used in Pediatric Care
Authors: Kovács Anita , Péter-Héderi Dóra , Perei Katalin , Budai-Szűcs Mária , Léber Attila , Gácsi Attila , Csányi Erzsébet , Berkó Szilvia
Published: August 2020

Semisolid dosage forms are recommended for the dermal care of babies and children. If we look at the ingredients of these preparations, there are still many cases in which there are substances (occlusive agents, preservatives) that no longer meet certain requirements of the modern age, so it is timely to replace them with other substances. The aim of this work was to formulate a science-based formulation with new components that keep or improve its moisturizing properties, rheological parameters, and microbiological stability. Occlusive oils, like white petrolatum and liquid paraffin and the preservative parabens are traditional ingredients in oil in water creams, were replaced with white beeswax, sunflower oil, and phenoxyethanol, respectively. Cocoa butter, urea, and glycerol were added to improve long-lasting hydration and support the barrier function of the reformulated creams. The rheological properties of the formulations were determined. The effects of the preparations on skin hydration and on the barrier function of the skin were tested. Furthermore, microbiological stability was investigated. The result of the reformulation was an o/w cream that provided a good longer-lasting hydration effect; supported the barrier function of the baby skin without occlusion; and had adequate consistency, easy spreading, a pleasant skin feeling, proper pH, and good microbiological stability.
Transungual Delivery, Anti-Inflammatory Activity, and In Vivo Assessment of a Cyclodextrin Polypseudorotaxanes Nail Lacquer
Authors: Fernández-Campos Francisco , Navarro Francesc , Corrales Adrian , Picas Jordi , Pena Eloy , González Jordi , Otero-Espinar Francisco J.
Published: August 2020

A new cyclodextrin polypseudorotaxanes nail lacquer (Regenail®) containing biotin, methyl sulphonyl methane (MSM), and dimethylsilanediol salicylate was developed and evaluated in vitro and in vivo. The product was developed to improve nail status and diminish signs of pathological nail alterations. A reference product (Betalfatrus®) was used for comparative purposes. An in vitro permeation experiment in hooves showed high MSM and biotin absorption. The content of sulfur and silicon in hooves was also found to be higher compared with the reference product. MSM was tested in human keratinocytes, exhibiting a good cytotoxicity profile and anti-inflammatory activity by the reduction in IL-8 and TNF-α under LPS stimuli. A clinical study was performed to check product safety and efficacy against nail brittleness and alterations such as Beau’s lines and onychorrhexis. A reduction in both alterations and in surface roughness without alteration of nail structure was observed, with a good level of patient acceptance and satisfaction.
Solid Lipid Nanoparticles for Duodenum Targeted Oral Delivery of Tilmicosin
Authors: Zhou Kaixiang , Yan Yuanyuan , Chen Dongmei , Huang Lingli , Li Chao , Meng Kuiyu , Wang Shuge , Algharib Samah Attia , Yuan Zonghui , Xie Shuyu
Published: August 2020

Developing a targeted oral delivery system to improve the efficacy of veterinary antibiotics and reduce their consumption and environmental risks is urgent. To achieve the duodenum-targeted release of tilmicosin, the enteric granule containing tilmicosin-loaded solid lipid nanoparticles (TIL-SLNs) was prepared based on its absorption site and transport characteristics. The in vitro release, release mechanisms, stability, palatability, and pharmacokinetics of the optimum enteric granules were studied. The intestine perfusion indicated that the main absorption site of tilmicosin was shifted to duodenum from ileum by TIL-SLNs, while, the absorption of TIL-SLNs in the duodenum was hindered by P-glycoprotein (P-gp). In contrast with TIL-SLNs, the TIL-SLNs could be more effectively delivered to the duodenum in intact form after enteric coating. Its effective permeability coefficient was enhanced when P-gp inhibitors were added. Compared to commercial premix, although the TIL-SLNs did not improve the oral absorption of tilmicosin, the time to reach peak concentration (Tmax) was obviously shortened. After the enteric coating of the granules containing SLNs and P-gp inhibitor of polysorbate-80, the oral absorption of tilmicosin was improved 2.72 fold, and the Tmax was shortened by 2 h. The combination of duodenum-targeted release and P-gp inhibitors was an effective method to improve the oral absorption of tilmicosin.
The Significance of Natural Product Derivatives and Traditional Medicine for COVID-19
Authors: Wang Dongdong , Huang Jiansheng , Yeung Andy Wai Kan , Tzvetkov Nikolay T. , Horbańczuk Jarosław O. , Willschke Harald , Gai Zhibo , Atanasov Atanas G.
Published: August 2020

Coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, there have been more than 10 million reported cases, more than 517,000 deaths in 215 countries, areas or territories. There is no effective antiviral medicine to prevent or treat COVID-19. Natural products and traditional medicine products with known safety profiles are a promising source for the discovery of new drug leads. There is increasing number of publications reporting the effect of natural products and traditional medicine products on COVID-19. In our review, we provide an overview of natural products and their derivatives or mimics, as well as traditional medicine products, which were reported to exhibit potential to inhibit SARS-CoV-2 infection in vitro, and to manage COVID-19 in vivo, or in clinical reports or trials. These natural products and traditional medicine products are categorized in several classes: (1) anti-malaria drugs including chloroquine and hydroxychloroquine, (2) antivirals including nucleoside analogs (remdesivir, favipiravir, β-D-N4-hydroxycytidine, ribavirin and among others), lopinavir/ritonavir and arbidol, (3) antibiotics including azithromycin, ivermectin and teicoplanin, (4) anti-protozoal drug, emetine, anti-cancer drug, homoharringtonine, and others, as well as (5) traditional medicine (Lian Hua Qing Wen Capsule, Shuang Huang Lian Oral Liquid, Qingfei Paidu Decoction and Scutellariae Radix). Randomized, double-blind and placebo-controlled large clinical trials are needed to provide solid evidence for the potential effective treatment. Currently, drug repurposing is a promising strategy to quickly find an effective treatment for COVID-19. In addition, carefully combined cocktails need to be examined for preventing a COVID-19 pandemic and the resulting global health concerns.
Deep Learning for Land Use and Land Cover Classification Based on Hyperspectral and Multispectral Earth Observation Data: A Review
Authors: Vali Ava , Comai Sara , Matteucci Matteo
Published: August 2020

Lately, with deep learning outpacing the other machine learning techniques in classifying images, we have witnessed a growing interest of the remote sensing community in employing these techniques for the land use and land cover classification based on multispectral and hyperspectral images; the number of related publications almost doubling each year since 2015 is an attest to that. The advances in remote sensing technologies, hence the fast-growing volume of timely data available at the global scale, offer new opportunities for a variety of applications. Deep learning being significantly successful in dealing with Big Data, seems to be a great candidate for exploiting the potentials of such complex massive data. However, there are some challenges related to the ground-truth, resolution, and the nature of data that strongly impact the performance of classification. In this paper, we review the use of deep learning in land use and land cover classification based on multispectral and hyperspectral images and we introduce the available data sources and datasets used by literature studies; we provide the readers with a framework to interpret the-state-of-the-art of deep learning in this context and offer a platform to approach methodologies, data, and challenges of the field.
Remote Sensing for Land Administration
Authors: Bennett Rohan , Oosterom Peter van , Lemmen Christiaan , Koeva Mila
Published: August 2020

Land administration constitutes the socio-technical systems that govern land tenure, use, value and development within a jurisdiction. The land parcel is the fundamental unit of analysis. Each parcel has identifiable boundaries, associated rights, and linked parties. Spatial information is fundamental. It represents the boundaries between land parcels and is embedded in cadastral sketches, plans, maps and databases. The boundaries are expressed in these records using mathematical or graphical descriptions. They are also expressed physically with monuments or natural features. Ideally, the recorded and physical expressions should align, however, in practice, this may not occur. This means some boundaries may be physically invisible, lacking accurate documentation, or potentially both. Emerging remote sensing tools and techniques offers great potential. Historically, the measurements used to produce recorded boundary representations were generated from ground-based surveying techniques. The approach was, and remains, entirely appropriate in many circumstances, although it can be timely, costly, and may only capture very limited contextual boundary information. Meanwhile, advances in remote sensing and photogrammetry offer improved measurement speeds, reduced costs, higher image resolutions, and enhanced sampling granularity. Applications of unmanned aerial vehicles (UAV), laser scanning, both airborne and terrestrial (LiDAR), radar interferometry, machine learning, and artificial intelligence techniques, all provide examples. Coupled with emergent societal challenges relating to poverty reduction, rapid urbanisation, vertical development, and complex infrastructure management, the contemporary motivation to use these new techniques is high. Fundamentally, they enable more rapid, cost-effective, and tailored approaches to 2D and 3D land data creation, analysis, and maintenance. This Special Issue hosts papers focusing on this intersection of emergent remote sensing tools and techniques, applied to domain of land administration.
Development of Land Surface Albedo Algorithm for the GK-2A/AMI Instrument
Authors: Lee Kyeong-Sang , Chung Sung-Rae , Lee Changsuk , Seo Minji , Choi Sungwon , Seong Noh-Hun , Jin Donghyun , Kang Minseok , Yeom Jong-Min , Roujean Jean-Louis , Jung Daeseong , Sim Suyoung , Han Kyung-Soo
Published: August 2020

The Korea Meteorological Administration successfully launched Korea’s next-generation meteorological satellite, Geo-KOMPSAT-2A (GK-2A), on 5 December 2018. It belongs to the new generation of GEO (Geostationary Elevation Orbit) satellite which offers capabilities to disseminate high spatial- (0.5–2 km) and high temporal-resolution (10 min) observations over a broad area, herein a geographic disk encompassing the Asia–Oceania region. The targeted objective is to enhance our understanding of climate change, owing to a bulk of coherent observations. For such, we developed an algorithm to map the land surface albedo (LSA), which is a major Essential Climate Variable (ECV). The retrieval algorithm devoted to GK-2A/Advanced Meteorological Imager (AMI) data considered Japan’s Himawari-8/Advanced Himawari Imager (AHI) data for prototyping, as this latter owns similar specifications to AMI. Our proposed algorithm is decomposed in three major steps: atmospheric correction, bidirectional reflectance distribution function (BRDF) modeling and angular integration, and narrow-to-broadband conversion. To perform BRDF modeling, the optimization method using normalized reflectance was applied, which improved the quality of BRDF modeling results, particularly when the number of observations was less than 15. A quality assessment was performed to compare our results to those of Moderate Resolution Imaging Spectroradiometer (MODIS) LSA products and ground measurement from Aerosol Robotic Network (AERONET) sites, Australian and New Zealand flux tower network (OzFlux) site and the Korea Flux Network (KoFlux) site from throughout 2017. Our results show dependable spatial and temporal consistency with MODIS broadband LSA data, and rapid changes in LSA due to snowfall and snow melting were well expressed in the temporal profile of our results. Our outcomes also show good agreement with the ground measurements from AERONET, OzFlux and KoFlux ground-based network with root mean square errors (RMSE) of 0.0223 and 0.0306, respectively, which is close to the accuracy of MODIS broadband LSA. Moreover, our results reveal still more reliable LSA products even when clouds are frequently present, such as during the summer monsoon season. It shows that our results are useful for continuous LSA monitoring.
Vegetation Detection Using Deep Learning and Conventional Methods
Authors: Ayhan Bulent , Kwan Chiman , Budavari Bence , Kwan Liyun , Lu Yan , Perez Daniel , Li Jiang , Skarlatos Dimitrios , Vlachos Marinos
Published: August 2020

Land cover classification with the focus on chlorophyll-rich vegetation detection plays an important role in urban growth monitoring and planning, autonomous navigation, drone mapping, biodiversity conservation, etc. Conventional approaches usually apply the normalized difference vegetation index (NDVI) for vegetation detection. In this paper, we investigate the performance of deep learning and conventional methods for vegetation detection. Two deep learning methods, DeepLabV3+ and our customized convolutional neural network (CNN) were evaluated with respect to their detection performance when training and testing datasets originated from different geographical sites with different image resolutions. A novel object-based vegetation detection approach, which utilizes NDVI, computer vision, and machine learning (ML) techniques, is also proposed. The vegetation detection methods were applied to high-resolution airborne color images which consist of RGB and near-infrared (NIR) bands. RGB color images alone were also used with the two deep learning methods to examine their detection performances without the NIR band. The detection performances of the deep learning methods with respect to the object-based detection approach are discussed and sample images from the datasets are used for demonstrations.
Ion Selective Amperometric Biosensors for Environmental Analysis of Nitrate, Nitrite and Sulfate
Authors: Revsbech Niels Peter , Nielsen Michael , Fapyane Deby
Published: August 2020

Inorganic ions that can be redox-transformed by living cells can be sensed by biosensors, where the redox transformation gives rise to a current in a measuring circuit. Such biosensors may be based on enzymes, or they may be based on application of whole cells. In this review focus will be on biosensors for the environmentally important ions NO3−, NO2−, and SO42−, and for comparison alternative sensor-based detection will also be mentioned. The developed biosensors are generally characterized by a high degree of specificity, but unfortunately also by relatively short lifetimes. There are several investigations where biosensor measurement of NO3− and NO2− have given new insight into the functioning of nitrogen transformations in man-made and natural environments such as sediments and biofilms, but the biosensors have not become routine tools. Future modifications resulting in better long-term stability may enable such general use.
Autonomous Scene Exploration for Robotics: A Conditional Random View-Sampling and Evaluation Using a Voxel-Sorting Mechanism for Efficient Ray Casting
Authors: Santos João , Oliveira Miguel , Arrais Rafael , Veiga Germano
Published: August 2020

Carrying out the task of the exploration of a scene by an autonomous robot entails a set of complex skills, such as the ability to create and update a representation of the scene, the knowledge of the regions of the scene which are yet unexplored, the ability to estimate the most efficient point of view from the perspective of an explorer agent and, finally, the ability to physically move the system to the selected Next Best View (NBV). This paper proposes an autonomous exploration system that makes use of a dual OcTree representation to encode the regions in the scene which are occupied, free, and unknown. The NBV is estimated through a discrete approach that samples and evaluates a set of view hypotheses that are created by a conditioned random process which ensures that the views have some chance of adding novel information to the scene. The algorithm uses ray-casting defined according to the characteristics of the RGB-D sensor, and a mechanism that sorts the voxels to be tested in a way that considerably speeds up the assessment. The sampled view that is estimated to provide the largest amount of novel information is selected, and the system moves to that location, where a new exploration step begins. The exploration session is terminated when there are no more unknown regions in the scene or when those that exist cannot be observed by the system. The experimental setup consisted of a robotic manipulator with an RGB-D sensor assembled on its end-effector, all managed by a Robot Operating System (ROS) based architecture. The manipulator provides movement, while the sensor collects information about the scene. Experimental results span over three test scenarios designed to evaluate the performance of the proposed system. In particular, the exploration performance of the proposed system is compared against that of human subjects. Results show that the proposed approach is able to carry out the exploration of a scene, even when it starts from scratch, building up knowledge as the exploration progresses. Furthermore, in these experiments, the system was able to complete the exploration of the scene in less time when compared to human subjects.
LoRaWAN Gateway Placement Model for Dynamic Internet of Things Scenarios
Authors: Matni Nagib , Moraes Jean , Oliveira Helder , Rosário Denis , Cerqueira Eduardo
Published: August 2020

Extended Range Wide Area Network (LoRaWAN) has recently gained a lot of attention from the industrial and research community for dynamic Internet of Things (IoT) applications. IoT devices broadcast messages for neighbor gateways that deliver the message to the application server through an IP network. Hence, it is required to deploy LoRaWAN gateways, i.e., network planning, and optimization, in an environment while considering Operational Expenditure (OPEX) and Capital Expenditure (CAPEX) along with Quality of Service (QoS) requirements. In this article, we introduced a LoRaWAN gateway placement model for dynamic IoT applications called DPLACE. It divides the IoT devices into groups with some degree of similarity between them to allow for the placement of LoRaWAN gateways that can serve these devices in the best possible way. Specifically, DPLACE computes the number of LoRaWAN gateways based on the Gap statistics method. Afterward, DPLACE uses K-Means and Fuzzy C-means algorithms to calculate the LoRaWAN gateway placement. The simulations’ results proved the benefits of DPLACE compared to state-of-the-art LoRaWAN gateway placement models in terms of OPEX, CAPEX, and QoS.
Evaluation of an IoT Application-Scoped Access Control Model over a Publish/Subscribe Architecture Based on FIWARE
Authors: Pozo Alejandro , Alonso Álvaro , Salvachúa Joaquín
Published: August 2020

The Internet of Things (IoT) brings plenty of opportunities to enhance society’s activities, from improving a factory’s production chain to facilitating people’s household tasks. However, it has also brought new security breaches, compromising privacy and authenticity. IoT devices are vulnerable to being accessed from the Internet; they lack sufficient resources to face cyber-attack threats. Keeping a balance between access control and the devices’ resource consumption has become one of the highest priorities of IoT research. In this paper, we evaluate an access control architecture based on the IAACaaS (IoT application-Scoped Access Control as a Service) model with the aim of protecting IoT devices that communicate using the Publish/Subscribe pattern. IAACaaS is based on the OAuth 2.0 authorization framework, which externalizes the identity and access control infrastructure of applications. In our evaluation, we implement the model using FIWARE Generic Enablers and deploy them for a smart buildings use case with a wireless communication. Then, we compare the performance of two different approaches in the data-sharing between sensors and the Publish/Subscribe broker, using Constrained Application Protocol (CoAP) and Hypertext Transfer Protocol (HTTP) protocols. We conclude that the integration of Publish/Subscribe IoT deployments with IAACaaS adds an extra layer of security and access control without compromising the system’s performance.
Wideband Dual-Polarized VHF Antenna for Space Observation Applications
Authors: Tatomirescu Alexandru , Badescu Alina
Published: August 2020

This work presents the design for an antenna element that can be used in radio arrays for the monitoring and detecting of radio emissions from cosmic particles’ interactions in the atmosphere. For these applications, the pattern stability over frequency is the primary design goal. The proposed antenna has a high gain over a relative bandwidth of 88%, a beamwidth of 2.13 steradians, a small group delay variation and a very stable radiation pattern across the frequency bandwidth of 110 to 190 MHz. It is dual polarized and has a simple mechanical structure which is easy and inexpensive to manufacture. The measurements show that the ground has insignificant impact on the overall radiation pattern.
In Vitro Antifungal and Topical Anti-Inflammatory Properties of Essential Oil from Wild-Growing Thymus vulgaris (Lamiaceae) Used for Medicinal Purposes in Algeria: A New Source of Carvacrol
Authors: Boukhatem Mohamed Nadjib , Darwish Noureldien H. E. , Sudha Thangirala , Bahlouli Siham , Kellou Dahbia , Benelmouffok Amina Bouchra , Chader Henni , Rajabi Mehdi , Benali Yasmine , Mousa Shaker A.
Published: August 2020

The aim of this study is to investigate the Thymus vulgaris essential oil (TVEO) as an antifungal agent in aromatherapy and/or as an active ingredient in the prevention or management of topical inflammatory diseases. The chemical composition of TVEO was determined with gas chromatography and revealed the presence of 25 compounds. Carvacrol was found to be the major component (56.8%). Antifungal action of TVEO was determined in vitro by using different methods. By the disc diffusion method, TVEO showed more potent antifungal activity against Candida strains than the positive control. The diameter of inhibition zone (DIZ) varied from 34 to 60 mm for Candida yeasts. Significantly higher antifungal activity was observed in the vapor phase at lower quantities. Candida albicans and C. parapsilosis were the most susceptible strains to the oil vapor with DIZ varying from 35 to 90 mm. The minimum inhibitory concentrations (MIC) of yeast were determined with an agar dilution method and revealed that MIC varied from 0.3 to 0.15 µL/mL for yeast species. The topical anti-inflammatory potential of TVEO was also explored in vivo with the croton oil-induced ear edema assay. TVEO exhibited a potent anti-inflammatory effect at all doses (100, 10 and 2 mg/kg), which were statistically similar (p > 0.05) to the positive control. This activity was also confirmed at the cellular level with histopathology analysis. Our results suggest the potential application of this carvacrol-rich TVEO in the prevention and management of fungal infections and topical inflammation and deserve further investigation for clinical applications. Furthermore, while the mode of action remains mainly undetermined and should be studied.
Perceptions of Customers as Sustained Competitive Advantages of Global Marketing Airline Alliances: A Hybrid Text Mining Approach
Authors: Seo Gang-Hoon , Itoh Munehiko
Published: August 2020

Over the past several decades, the aviation industry has been reshaped, centering on global alliances, and these have grown exponentially. However, it is still not clear whether they are achieving sustained competitive advantages, and what are the specific competitive advantages of the three alliances (oneworld, SkyTeam, Star Alliance) arising on the customer side. This study aims to examine whether global alliance groups outperform the non-alliance group, how the three alliances differ regarding passengers’ perceptions, and what their competitive advantages are. A hybrid text mining analysis was adopted as this study’s method. Frequency tests, t-tests, one-way analysis of variance tests, and three-step mediated regression analyses were performed using 6393 ordinal and word-of-mouth (WOM) data. We found that the degree of passengers’ perceptions of alliances was low, the non-alliance group outperformed the alliance groups, and there were no significant differences between alliances on service rating and sentiment score. Only oneworld has competitive advantages that link to passengers’ service rating and sentiment score. These findings imply that alliances could not ensure competitive advantages that derive from customers’ perceptions, and although passengers partly perceived several selling points, their differentiation strategies are not successful.
A Model Process of Integrating Context of Local Culture for Pre-Development Stage in the Design of Cultural and Creative Products—Using Macao’s Historical Buildings as an Example
Authors: Zhang Xizhi , Wen Kuo-Hsun
Published: August 2020

In the context of the research on local architectural culture of Macao, this paper explores how architecture’s cultural elements can be integrated into cultural and creative product design at the pre-development stage. Therefore, local culture can be effectively disseminated through the medium of cultural and creative products. However, in the process of product design, seemingly, designers often rely on their experience as the main way to develop ideas and designs. This approach can fall short in generating sufficient cognition and interpretation between culture and product design, and the product may fail to truly reflect cultural and creative values. This paper focuses on the cultural elements and the designer’s cognition in design development of cultural and creative products. It applies theoretical concepts of Kansei engineering theory as the basis, and, combined with the Semantic Differential Method, tries to extract the most powerful product image elements that influence designers for better understanding of the cultural elements in design development. This paper aims to employ scientific methods to enable designers to better develop designs with cultural and creative connotations, thereby improving the success rate of cultural and creative products. It further proposes a model process of image perception to be employed by designers in early design research and the development stage. By enhancing the resonance of cultural elements for cultural and creative products, the model may shorten the perceptual distance between the designer and the local culture, improve the designer’s product development efficiency, and increase consumer satisfaction with the design outcome through added cultural and creative value. As such, the model can optimize the design development for cultural and creative products to achieve the public’s aesthetic and cultural expectations, as well as for a sustainable design approach.
Farmers’ Adoption Preferences for Sustainable Agriculture Practices in Northwest China
Authors: Nong Yixin , Yin Changbin , Yi Xiaoyan , Ren Jing , Chien Hsiaoping
Published: August 2020

In the highest soil erosion regions of arid and semiarid northwest China, water resource deficits and farmland misuse have further exacerbated soil degradation. Therefore, understanding how farmers in diverse agroclimatic zones perceive and respond to different conservation practices is important to the implementation of sustainable agriculture practices (SAPs). To this end, this study uses a best–worst scaling approach to examine the adoption preferences for nine SAPs among grain and cash crop farmers and investigates the influence of farm and climatic characteristics on adoption preferences based on a face to face survey of 554 households in Gansu province, which is classified as an arid and semiarid area in northwest China. Both grain and cash crop farmers had stronger preferences for the practices of using organic instead of chemical fertilizers and of improving irrigation practices. In addition, while cash crop farmers also had strong preferences for cover crop-related practices, they preferred long-term fallows least. Household income, livestock, and precipitation influence the potential perceived importance of SAPs. The different perceived importance of these practices suggests new possible combinations or packages for a sustainable agriculture program during the cropping structure adjustment in Gansu.
State-of-the-Art Review of Microbial-Induced Calcite Precipitation and Its Sustainability in Engineering Applications
Authors: Rahman Md Mizanur , Hora Reena N. , Ahenkorah Isaac , Beecham Simon , Karim Md Rajibul , Iqbal Asif
Published: August 2020

Microbial-induced calcite precipitation (MICP) is a promising new technology in the area of Civil Engineering with potential to become a cost-effective, environmentally friendly and sustainable solution to many problems such as ground improvement, liquefaction remediation, enhancing properties of concrete and so forth. This paper reviews the research and developments over the past 25 years since the first reported application of MICP in 1995. Historical developments in the area, the biological processes involved, the behaviour of improved soils, developments in modelling the behaviour of treated soil and the challenges associated are discussed with a focus on the geotechnical aspects of the problem. The paper also presents an assessment of cost and environmental benefits tied with three application scenarios in pavement construction. It is understood for some applications that at this stage, MICP may not be a cost-effective or even environmentally friendly solution; however, following the latest developments, MICP has the potential to become one.