bluuebunny/crossref_metadata_2025 huggingface dataset:
Onboard Visual Horizon Detection for Unmanned Aerial Systems with Programmable Logic
Authors: Hiba Antal , Sántha Levente Márk , Zsedrovits Tamás , Hajder Levente , Zarandy Akos
Published: April 2020

We introduce and analyze a fast horizon detection algorithm with native radial distortion handling and its implementation on a low power field programmable gate array (FPGA) development board in this paper. The algorithm is suited for visual applications in an airborne environment, that is on board a small unmanned aircraft. The algorithm was designed to have low complexity because of the power consumption requirements. To keep the computational cost low, an initial guess for the horizon is used, which is provided by the attitude heading reference system of the aircraft. The camera model takes radial distortions into account, which is necessary for a wide-angle lens used in most applications. This paper presents formulae for distorted horizon lines and a gradient sampling-based resolution-independent single shot algorithm for finding a horizon with radial distortion without undistortion of the complete image. The implemented algorithm is part of our visual sense-and-avoid system, where it is used for the sky-ground separation, and the performance of the algorithm is tested on real flight data. The FPGA implementation of the horizon detection method makes it possible to add this efficient module to any FPGA-based vision system.
Tree Ring-Based Estimation of Landslide Areal Reactivation as a Fundament of Magnitude–Frequency Assessment
Authors: Šilhán Karel
Published: April 2020

Magnitude–frequency (M–F) relationships represent important information on slope deformation and are used in hazard assessment or as supporting data for urban planning. Various approaches have been used to extract such relationships in the past, but most of these methods drove at the problem of exact events´ frequency determination. Dendrogeomorphic (tree ring-based) approaches are actually thought to be the most precise method of dating past mass movement events that occurred within the last several centuries. Together with information on the spatial positions of the analysed trees, they represent a potentially very valuable tool for reconstructing M–F relationships, although their use for this purpose has been very rare in the past. In this study, M–F relationships are reconstructed using dendrogeomorphic methods for three landslides of different types (a translational slide, a flow-like slide, and a rotational slide) occurring in different geological materials (thick-bedded flysch, limestone marls, and volcanic breccia). In total, 572 disturbed trees were analysed, and chronologies of mass movement events were built. Landslide magnitudes were expressed in three ways: (i) the value of the standard It index; (ii) the area, as determined using homogenous morphological units; and (iii) the area, as determined using tree buffers. The power-law nature of M–F relationships was confirmed for all the landslides that were studied and using all the approaches that were applied. All of the combinations of results yielded high correlation values; nevertheless, differences were noted. The advantages and limitations of each approach used to reconstruct M–F relationships are also discussed.
Transmission of Orbital Angular Momentum and Cylindrical Vector Beams in a Large-Bandwidth Annular Core Photonic Crystal Fiber
Authors: Sharma Manish , Amirkhan Fatemeh , Mishra Satyendra , Sengupta Dipankar , Messaddeq Younès , Blanchard François , Ung Bora
Published: April 2020

The stable propagation of orbital angular momentum and cylindrical vector beams in a newly designed annular core photonic crystal fiber (AC-PCF) tailored for the broadband single-radial order beam transmission (within the so-called “endlessly mono-radial” guiding regime) is demonstrated for the first time. It is shown that the vector-vortex beams can maintain high mode purities above 18 dB after propagation in the fiber under test over all of the wavelength range from 805 to 845 nm (over 17 THz bandwidth) investigated with the help of a tunable laser and an S-plate for the generation of singular beams in free space. Our results confirm that the AC-PCF is a promising design for the broadband transmission of vector-vortex beams that have potential applications in space-division multiplexing, quantum communications, optical sensing and trapping.
Increased Angiogenesis and Lymphangiogenesis in the Placental Villi of Women with Chronic Venous Disease during Pregnancy
Authors: Ortega Miguel A , Saez Miguel A , Fraile-Martínez Oscar , Asúnsolo Ángel , Pekarek Leonel , Bravo Coral , Coca Santiago , Sainz Felipe , Mon Melchor Álvarez- , Buján Julia , García-Honduvilla Natalio
Published: April 2020

Pregnancy is a period in a woman’s life associated with an increased risk of developing lower extremity chronic venous disease (CVD). Pregnancy-associated CVD is associated with changes in placental villi. We investigated angiogenesis and lymphangiogenesis in the placental villi of women with CVD during pregnancy compared with healthy controls with no history of CVD (HC). An observational, analytical, and prospective cohort study was conducted on 114 women in their third trimester of pregnancy (32 weeks). Sixty-two participants were clinically diagnosed with CVD. In parallel, 52 controls with no history of CVD (HC) were studied. Gene and protein expression of CD31, podoplanin (D2-40), Flt-1, and placental growth factor (PIGF) was analysed by real-time polymerase chain reaction (RT-qPCR) and immunohistochemistry. CD31 and D2-40 gene expression was significantly greater in the placental villi of women with CVD, as were the numbers of vessels positive for CD31 and D2-40. Significantly higher gene and protein expression of Flt-1 and PIGF was observed in the placental villi of women with CVD. Histological analysis showed more placental villi with periodic acid of Schiff (PAS)-positive material in women with CVD. Our results show a connection between pregnancy-associated CVD and leading to higher proangiogenic and lymphangiogenic activity in placental villi.
Pilocarpine Induced Behavioral and Biochemical Alterations in Chronic Seizure-Like Condition in Adult Zebrafish
Authors: Paudel Yam Nath , Kumari Yatinesh , Abidin Syafiq Asnawi Zainal , Othman Iekhsan , Shaikh Mohd. Farooq
Published: April 2020

Epilepsy is a devastating neurological condition exhibited by repeated spontaneous and unpredictable seizures afflicting around 70 million people globally. The basic pathophysiology of epileptic seizures is still elusive, reflecting an extensive need for further research. Developing a novel animal model is crucial in understanding disease mechanisms as well as in assessing the therapeutic target. Most of the pre-clinical epilepsy research has been focused on rodents. Nevertheless, zebrafish disease models are relevant to human disease pathophysiology hence are gaining increased attention nowadays. The current study for the very first time developed a pilocarpine-induced chronic seizure-like condition in adult zebrafish and investigated the modulation in several neuroinflammatory genes and neurotransmitters after pilocarpine exposures. Seizure score analysis suggests that compared to a single dose, repeated dose pilocarpine produces chronic seizure-like effects maintaining an average seizure score of above 2 each day for a minimum of 10 days. Compared to the single dose pilocarpine treated group, there was increased mRNA expression of HMGB1, TLR4, TNF-α, IL-1, BDNF, CREB-1, and NPY; whereas decreased expression of NF-κB was upon the repeated dose of pilocarpine administration. In addition, the epileptic group demonstrates modulation in neurotransmitters levels such as GABA, Glutamate, and Acetylcholine. Moreover, proteomic profiling of the zebrafish brain from the normal and epileptic groups from LCMS/MS quantification detected 77 and 13 proteins in the normal and epileptic group respectively. Summing up, the current investigation depicted that chemically induced seizures in zebrafish demonstrated behavioral and molecular alterations similar to classical rodent seizure models suggesting the usability of adult zebrafish as a robust model to investigate epileptic seizures.
Advances on Chelation and Chelator Metal Complexes in Medicine
Authors: Kontoghiorghes George J.
Published: April 2020

Metal ions such as iron, copper and zinc are essential for life [...]
Therapeutic Effect of Seaweed Derived Xanthophyl Carotenoid on Obesity Management; Overview of the Last Decade
Authors: Ojulari Oyindamola Vivian , Lee Seul Gi , Nam Ju-Ock
Published: April 2020

Present-day lifestyles associated with high calorie-fat intake and accumulation, as well as energy imbalance, have led to the development of obesity and its comorbidities, which have emerged as some of the major health issues globally. To combat the disease, many studies have reported the anti-obesity effects of natural compounds in foods, with some advantages over chemical treatments. Carotenoids, such as xanthophyll derived from seaweeds, have attracted the attention of researchers due to their notable biological activities, which are associated mainly with their antioxidant properties. Their involvement in oxidative stress modulation, the regulation of major transcription factors and enzymes, and their antagonistic effects on various obesity parameters have been examined in both in vitro and in vivo studies. The present review is a collation of published research over the last decade on the antioxidant properties of seaweed xanthophyll carotenoids, with a focus on fucoxanthin and astaxanthin and their mechanisms of action in obesity prevention and treatment.
Pathogenesis of Mucopolysaccharidoses, an Update
Authors: Fecarotta Simona , Tarallo Antonietta , Damiano Carla , Minopoli Nadia , Parenti Giancarlo
Published: April 2020

The recent advancements in the knowledge of lysosomal biology and function have translated into an improved understanding of the pathophysiology of mucopolysaccharidoses (MPSs). The concept that MPS manifestations are direct consequences of lysosomal engorgement with undegraded glycosaminoglycans (GAGs) has been challenged by new information on the multiple biological roles of GAGs and by a new vision of the lysosome as a signaling hub involved in many critical cellular functions. MPS pathophysiology is now seen as the result of a complex cascade of secondary events that lead to dysfunction of several cellular processes and pathways, such as abnormal composition of membranes and its impact on vesicle fusion and trafficking; secondary storage of substrates; impairment of autophagy; impaired mitochondrial function and oxidative stress; dysregulation of signaling pathways. The characterization of this cascade of secondary cellular events is critical to better understand the pathophysiology of MPS clinical manifestations. In addition, some of these pathways may represent novel therapeutic targets and allow for the development of new therapies for these disorders.
A Machine Learning-Based Identification of Genes Affecting the Pharmacokinetics of Tacrolimus Using the DMETTM Plus Platform
Authors: Gim Jeong-An , Kwon Yonghan , Lee Hyun A , Lee Kyeong-Ryoon , Kim Soohyun , Choi Yoonjung , Kim Yu Kyong , Lee Howard
Published: April 2020

Tacrolimus is an immunosuppressive drug with a narrow therapeutic index and larger interindividual variability. We identified genetic variants to predict tacrolimus exposure in healthy Korean males using machine learning algorithms such as decision tree, random forest, and least absolute shrinkage and selection operator (LASSO) regression. rs776746 (CYP3A5) and rs1137115 (CYP2A6) are single nucleotide polymorphisms (SNPs) that can affect exposure to tacrolimus. A decision tree, when coupled with random forest analysis, is an efficient tool for predicting the exposure to tacrolimus based on genotype. These tools are helpful to determine an individualized dose of tacrolimus.
Pioglitazone-Mediated Peroxisome Proliferator-Activated Receptor γ Activation Aggravates Murine Immune-Mediated Hepatitis
Authors: Schulte Rike , Wohlleber Dirk , Unrau Ludmilla , Geers Bernd , Metzger Christina , Erhardt Annette , Tiegs Gisa , van Rooijen Nico , Heukamp Lukas C. , Klotz Luisa , Knolle Percy A. , Diehl Linda
Published: April 2020

The nuclear receptor peroxisome proliferator-activated receptor gamma (PPARγ) regulates target gene expression upon ligand binding. Apart from its effects on metabolism, PPARγ activity can inhibit the production of pro-inflammatory cytokines by several immune cells, including dendritic cells and macrophages. In chronic inflammatory disease models, PPARγ activation delays the onset and ameliorates disease severity. Here, we investigated the effect of PPARγ activation by the agonist Pioglitazone on the function of hepatic immune cells and its effect in a murine model of immune-mediated hepatitis. Cytokine production by both liver sinusoidal endothelial cells (IL-6) and in T cells ex vivo (IFNγ) was decreased in cells from Pioglitazone-treated mice. However, PPARγ activation did not decrease pro-inflammatory tumor necrosis factor alpha TNFα production by Kupffer cells after Toll-like receptor (TLR) stimulation ex vivo. Most interestingly, although PPARγ activation was shown to ameliorate chronic inflammatory diseases, it did not improve hepatic injury in a model of immune-mediated hepatitis. In contrast, Pioglitazone-induced PPARγ activation exacerbated D-galactosamine (GalN)/lipopolysaccharide (LPS) hepatitis associated with an increased production of TNFα by Kupffer cells and increased sensitivity of hepatocytes towards TNFα after in vivo Pioglitazone administration. These results unravel liver-specific effects of Pioglitazone that fail to attenuate liver inflammation but rather exacerbate liver injury in an experimental hepatitis model.
Zeb2 Regulates Myogenic Differentiation in Pluripotent Stem Cells
Authors: Di Filippo Ester Sara , Costamagna Domiziana , Giacomazzi Giorgia , Cortés-Calabuig Álvaro , Stryjewska Agata , Huylebroeck Danny , Fulle Stefania , Sampaolesi Maurilio
Published: April 2020

Skeletal muscle differentiation is triggered by a unique family of myogenic basic helix-loop-helix transcription factors, including MyoD, MRF-4, Myf-5, and Myogenin. These transcription factors bind promoters and distant regulatory regions, including E-box elements, of genes whose expression is restricted to muscle cells. Other E-box binding zinc finger proteins target the same DNA response elements, however, their function in muscle development and regeneration is still unknown. Here, we show that the transcription factor zinc finger E-box-binding homeobox 2 (Zeb2, Sip-1, Zfhx1b) is present in skeletal muscle tissues. We investigate the role of Zeb2 in skeletal muscle differentiation using genetic tools and transgenic mouse embryonic stem cells, together with single-cell RNA-sequencing and in vivo muscle engraftment capability. We show that Zeb2 over-expression has a positive impact on skeletal muscle differentiation in pluripotent stem cells and adult myogenic progenitors. We therefore propose that Zeb2 is a novel myogenic regulator and a possible target for improving skeletal muscle regeneration. The non-neural roles of Zeb2 are poorly understood.
Sucrose Phosphorylase and Related Enzymes in Glycoside Hydrolase Family 13: Discovery, Application and Engineering
Authors: Franceus Jorick , Desmet Tom
Published: April 2020

Sucrose phosphorylases are carbohydrate-active enzymes with outstanding potential for the biocatalytic conversion of common table sugar into products with attractive properties. They belong to the glycoside hydrolase family GH13, where they are found in subfamily 18. In bacteria, these enzymes catalyse the phosphorolysis of sucrose to yield α-glucose 1-phosphate and fructose. However, sucrose phosphorylases can also be applied as versatile transglucosylases for the synthesis of valuable glycosides and sugars because their broad promiscuity allows them to transfer the glucosyl group of sucrose to a diverse collection of compounds other than phosphate. Numerous process and enzyme engineering studies have expanded the range of possible applications of sucrose phosphorylases ever further. Moreover, it has recently been discovered that family GH13 also contains a few novel phosphorylases that are specialised in the phosphorolysis of sucrose 6F-phosphate, glucosylglycerol or glucosylglycerate. In this review, we provide an overview of the progress that has been made in our understanding and exploitation of sucrose phosphorylases and related enzymes over the past ten years.
Effect of Pharmacological Inhibition of the Catalytic Activity of Phosphatases of Regenerating Liver in Early T Cell Receptor Signaling Dynamics and IL-2 Production
Authors: Aguilar-Sopeña Oscar , Hernández-Pérez Sara , Alegre-Gómez Sergio , Castro-Sánchez Patricia , Iglesias-Ceacero Alba , Lazo John S. , Roda-Navarro Pedro
Published: April 2020

We have previously shown the delivery of phosphatase of regenerating liver-1 (PRL-1) to the immunological synapse (IS) and proposed a regulatory role of the catalytic activity of PRLs (PRL-1, PRL-2 and PRL-3) in antigen-induced IL-2 production. Nonetheless, the expression in T cells and delivery to the IS of the highly homologous PRL-3, as well as the role of the catalytic activity of PRLs in antigen-induced early signaling, has not been investigated. Here, the expression of PRL-3 protein was detected in primary CD4 T cells and in the CD4 T cell line Jurkat (JK), in which an overexpressed GFP-PRL-3 fluorescent fusion protein trafficked through the endosomal recycling compartment and co-localized with PLCγ1 signaling sites at the IS. Pharmacological inhibition was used to compare the role of the catalytic activity of PRLs in antigen-induced early signaling and late IL-2 production. Although the phosphatase activity of PRLs was not critical for early signaling triggered by antigen, it seemed to regulate signaling dynamics and was necessary for proper IL-2 production. We propose that enzymatic activity of PRLs has a higher significance for cytokine production than for early signaling at the IS. However, further research will be necessary to deeply understand the regulatory role of PRLs during lymphocyte activation and effector function.
In Silico Studies on Triterpenoid Saponins Permeation through the Blood–Brain Barrier Combined with Postmortem Research on the Brain Tissues of Mice Affected by Astragaloside IV Administration
Authors: Stępnik Katarzyna , Kukula-Koch Wirginia
Published: April 2020

As the number of central nervous system (CNS) drug candidates is constantly growing, there is a strong need for precise a priori prediction of whether an administered compound is able to cross the blood–brain barrier (BBB). The aim of this study was to evaluate the ability to cross the BBB of triterpenoid saponins occurring in Astragalus mongholicus roots. The research was carried out using in silico methods combined with postmortem studies on the brain tissues of mice treated with isolated astragaloside IV (AIV). Firstly, to estimate the ability to cross the BBB by the tested saponins, new quantitative structure–activity relationship (QSAR) models were established. The reliability and predictability of the model based on the values of the blood–brain barrier penetration descriptor (logBB), the difference between the n-octanol/water and cyclohexane/water logP (ΔlogP), the logarithm of n-octanol/water partition coefficient (logPow), and the excess molar refraction (E) were both confirmed using the applicability domain (AD). The critical leverage value h* was found to be 0.128. The relationships between the standardized residuals and the leverages were investigated here. The application of an in vitro acetylcholinesterase-inhibition test showed that AIV can be recognized as the strongest inhibitor among the tested compounds. Therefore, it was isolated for the postmortem studies on brain tissues and blood using semi-preparative HPLC with the mobile phase composed of water, methanol, and ethyl acetate (1.7:2.1:16.2 v/v/v). The results of the postmortem studies on the brain tissues show a regular dependence of the final concentration of AIV in the analyzed brain samples of animals treated with 12.5 and 25 mg/kg b.w. of AIV (0.00012299 and 0.0002306 mg, respectively, per one brain). Moreover, the AIV logBB value was experimentally determined and found to be equal to 0.49 ± 0.03.
Nanoparticles Modified with Cell-Penetrating Peptides: Conjugation Mechanisms, Physicochemical Properties, and Application in Cancer Diagnosis and Therapy
Authors: Gessner Isabel , Neundorf Ines
Published: April 2020

Based on their tunable physicochemical properties and the possibility of producing cell-specific platforms through surface modification with functional biomolecules, nanoparticles (NPs) represent highly promising tools for biomedical applications. To improve their potential under physiological conditions and to enhance their cellular uptake, combinations with cell-penetrating peptides (CPPs) represent a valuable strategy. CPPs are often cationic peptide sequences that are able to translocate across biological membranes and to carry attached cargos inside cells and have thus been recognized as versatile tools for drug delivery. Nevertheless, the conjugation of CPP to NP surfaces is dependent on many properties from both individual components, and further insight into this complex interplay is needed to allow for the fabrication of highly stable but functional vectors. Since CPPs per se are nonselective and enter nearly all cells likewise, additional decoration of NPs with homing devices, such as tumor-homing peptides, enables the design of multifunctional platforms for the targeted delivery of chemotherapeutic drugs. In this review, we have updated the recent advances in the field of CPP-NPs, focusing on synthesis strategies, elucidating the influence of different physicochemical properties, as well as their application in cancer research.
Argania Spinosa Fruit Shell Extract-Induced Melanogenesis via cAMP Signaling Pathway Activation
Authors: Makbal Rachida , Villareal Myra O. , Gadhi Chemseddoha , Hafidi Abdellatif , Isoda Hiroko
Published: April 2020

We have previously reported that argan oil and argan press-cake from the kernels of Argania spinosa have an anti-melanogenesis effect. Here, the effect of argan fruit shell ethanol extract (AFSEE) on melanogenesis in B16F10 cells was determined, and the mechanism underlying its effect was elucidated. The proliferation of AFSEE-treated B16F10 cells was evaluated using the 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay, while the melanin content was quantified using a spectrophotometric method. The expression of melanogenesis-related proteins was determined by Western blot and real-time PCR, while global gene expression was determined using a DNA microarray. In vitro analysis results showed that the melanin content of B16F10 cells was significantly increased by AFSEE, without cytotoxicity, by increasing the melanogenic enzyme tyrosinase (TRY), tyrosinase related-protein 1 (TRP1), and dopachrome tautomerase (DCT) protein and mRNA expression, as well as upregulating microphthalmia-associated transcription factor (MITF) expression through mitogen-activated protein kinases (MAPKs) extracellular signal-regulated kinase (ERK) and p38, and the cyclic adenosine monophosphate (cAMP) signaling pathway, as indicated by the microarray analysis results. AFSEE’s melanogenesis promotion effect is primarily attributed to its polyphenolic components. In conclusion, AFSEE promotes melanogenesis in B16F10 cells by upregulating the expression of the melanogenic enzymes through the cAMP–MITF signaling pathway.AFSEE may be used as a cosmetics product component to promote melanogenesis, or as a therapeutic against hypopigmentation disorders.
Second Tier Molecular Genetic Testing in Newborn Screening for Pompe Disease: Landscape and Challenges
Authors: Smith Laurie D. , Bainbridge Matthew N. , Parad Richard B. , Bhattacharjee Arindam
Published: April 2020

Pompe disease (PD) is screened by a two tier newborn screening (NBS) algorithm, the first tier of which is an enzymatic assay performed on newborn dried blood spots (DBS). As first tier enzymatic screening tests have false positive results, an immediate second tier test on the same sample is critical in resolving newborn health status. Two methodologies have been proposed for second tier testing: (a) measurement of enzymatic activities such as of Creatine/Creatinine over alpha-glucosidase ratio, and (b) DNA sequencing (a molecular genetics approach), such as targeted next generation sequencing. (tNGS). In this review, we discuss the tNGS approach, as well as the challenges in providing second tier screening and follow-up care. While tNGS can predict genotype-phenotype effects when known, these advantages may be diminished when the variants are novel, of unknown significance or not discoverable by current test methodologies. Due to the fact that criticisms of screening algorithms that utilize tNGS are based on perceived complexities, including variant detection and interpretation, we clarify the actual limitations and present the rationale that supports optimizing a molecular genetic testing approach with tNGS. Second tier tNGS can benefit clinical decision-making through the use of the initial NBS DBS punch and rapid turn-around time methodology for tNGS, that includes copy number variant analysis, variant effect prediction, and variant ‘cut-off’ tools for the reduction of false positive results. The availability of DNA sequence data will contribute to the improved understanding of genotype-phenotype associations and application of treatment. The ultimate goal of second tier testing should enable the earliest possible diagnosis for the earliest initiation of the most effective clinical interventions in infants with PD.
Non-Contact Driver Respiration Rate Detection Technology Based on Suppression of Multipath Interference with Directional Antenna
Authors: Yang Fan , He Zhiming , Guo Shisheng , Fu Yuanhua , Li Liang , Lu Junfeng , Jiang Kui
Published: April 2020

Non-contact driver respiration rate detection is a challenging problem in the Internet of Vehicles, because the automobile environment is much narrower, and thus the multipath effect is greater. To overcome these challenges, a 2.4 GHz continuous wave forward-scattering radar respiratory detection system is proposed based on the theory that the radar cross-section (RCS) of the human body changes with human breathing. We also analyze the impact of the multipath effect in the vehicle on the received radar signal and compare the output signal captured by a directional antenna with that captured by an omnidirectional antenna in the proposed system. In addition, the mean value of the received signal’s envelope is used to judge whether the driver’s posture is reasonable. Finally, compared with the existing contact respiratory detection system, the actual test results demonstrate the effectiveness of the proposed FSR system, and the driver respiration rates obtained by the proposed system are consistent with those obtained by the contact respiratory detection system.
A Situation Assessment Method with an Improved Fuzzy Deep Neural Network for Multiple UAVs
Authors: Zhang Lin , Zhu Yian , Shi Xianchen , Li Xuesi
Published: April 2020

To improve the intelligence and accuracy of the Situation Assessment (SA) in complex scenes, this work develops an improved fuzzy deep neural network approach to the situation assessment for multiple Unmanned Aerial Vehicle(UAV)s. Firstly, this work normalizes the scene data based on time series and use the normalized data as the input for an improved fuzzy deep neural network. Secondly, adaptive momentum and Elastic SGD (Elastic Stochastic Gradient Descent) are introduced into the training process of the neural network, to improve the learning performance. Lastly, in the real-time situation assessment task for multiple UAVs, conventional methods often bring inaccurate results for the situation assessment because these methods don’t consider the fuzziness of task situations. This work uses an improved fuzzy deep neural network to calculate the results of situation assessment and normalizes these results. Then, the degree of trust of the current result, relative to each situation label, is calculated with the normalized results using fuzzy logic. Simulation results show that the proposed method outperforms competitors.
Skin-Compatible Biobased Beauty Masks Prepared by Extrusion
Authors: Coltelli Maria-Beatrice , Panariello Luca , Morganti Pierfrancesco , Danti Serena , Baroni Adone , Lazzeri Andrea , Fusco Alessandra , Donnarumma Giovanna
Published: April 2020

In the cosmetic sector, natural and sustainable products with a high compatibility with skin, thus conjugating wellness with a green-oriented consumerism, are required by the market. Poly(hydroxyalkanoate) (PHA)/starch blends represent a promising alternative to prepare flexible films as support for innovative beauty masks, wearable after wetting and releasing starch and other selected molecules. Nevertheless, preparing these films by extrusion is difficult due to the high viscosity of the polymer melt at the temperature suitable for processing starch. The preparation of blends including poly(butylene succinate-co-adipate) (PBSA) or poly(butylene adipate-co-terephthalate) (PBAT) was investigated as a strategy to better modulate melt viscosity in view of a possible industrial production of beauty mask films. The release properties of films in water, connected to their morphology, was also investigated by extraction trials, infrared spectroscopy and stereo and electron microscopy. Then, the biocompatibility with cells was assessed by considering both mesenchymal stromal cells and keratinocytes. All the results were discussed considering the morphology of the films. This study evidenced the possibility of modulating thanks to the selection of composition and the materials processing of the properties necessary for producing films with tailored properties and processability for beauty masks.
Electronic Navigational Charts: International Standards and Map Projections
Authors: Palikaris Athanasios , Mavraeidopoulos Athanasios K.
Published: April 2020

Electronic navigational charts (ENCs) are geospatial databases, compiled for the operational use of Electronic Chart Display and Information systems (ECDIS) according to strict technical specifications of the International Hydrographic Organization (IHO). ECDIS is a GIS system designed for marine navigation according to the relevant standards of the International Maritime Organization (IMO). The international standards for ENCs and ECDIS, issued by the IHO and IMO, cover many aspects of the portrayal of ENCs in ECDIS but do not specify or recommend map projections. Consequently, in some cases, the unjustified employment of map projections by the manufacturers has caused certain functional drawbacks and inadequacies. This article reviews, evaluates and supplements the results of earlier studies on the selection of map projections for the depiction of ENCs in ECDIS and proposes a reasonable set of suitable projections with pertinent selection/implementation rules. These proposals took into consideration that ECDIS users (navigators) are not GIS experts or professional cartographers and consequently, the proposed election/implementation rules have to be simple and straightforward.
Community-Led Green Land Acquisition: Social Innovative Initiatives for Forest Protection and Regional Development
Authors: Castro-Arce Karina , Vanclay Frank
Published: April 2020

Land acquisition often involves power and displacement and can be carried out on a large scale. There are many forms of land acquisition, including for environmental and conservation purposes as well as for production activities. While green grabbing has joined land grabbing as an environmental justice issue of concern, it is not necessarily the case that all green land acquisition is large scale, done by powerful outsiders, or leads to displacement and exclusion. The outcomes of green land acquisition are dependent on the mechanisms used, the adequacy of resettlement and/or compensation, and the social and environmental context in which it happens. We discuss the outcomes of community-led land acquisition for conservation purposes in Costa Rica. We considered a special case of green land acquisition done by local civil society to defend the forest and water resources of the Juan Castro Blanco National Water Park in Costa Rica. We used the literature on green grabbing, social ecological systems, and social innovation to discuss local environmental governance and regional sustainable development. This paper makes a fresh contribution to environmental planning and environmental governance by bringing in aspects of green land acquisition that have not been previously explored.
Variance Reduction of Sequential Monte Carlo Approach for GNSS Phase Bias Estimation
Authors: Tian Yumiao , Ge Maorong , Neitzel Frank
Published: April 2020

Global navigation satellite systems (GNSS) are an important tool for positioning, navigation, and timing (PNT) services. The fast and high-precision GNSS data processing relies on reliable integer ambiguity fixing, whose performance depends on phase bias estimation. However, the mathematic model of GNSS phase bias estimation encounters the rank-deficiency problem, making bias estimation a difficult task. Combining the Monte-Carlo-based methods and GNSS data processing procedure can overcome the problem and provide fast-converging bias estimates. The variance reduction of the estimation algorithm has the potential to improve the accuracy of the estimates and is meaningful for precise and efficient PNT services. In this paper, firstly, we present the difficulty in phase bias estimation and introduce the sequential quasi-Monte Carlo (SQMC) method, then develop the SQMC-based GNSS phase bias estimation algorithm, and investigate the effects of the low-discrepancy sequence on variance reduction. Experiments with practical data show that the low-discrepancy sequence in the algorithm can significantly reduce the standard deviation of the estimates and shorten the convergence time of the filtering.
A Mathematical Pre-Disaster Model with Uncertainty and Multiple Criteria for Facility Location and Network Fortification
Authors: Monzón Julia , Liberatore Federico , Vitoriano Begoña
Published: April 2020

Disasters have catastrophic effects on the affected population, especially in developing and underdeveloped countries. Humanitarian Logistics models can help decision-makers to efficiently and effectively warehouse and distribute emergency goods to the affected population, to reduce casualties and suffering. However, poor planning and structural damage to the transportation infrastructure could hamper these efforts and, eventually, make it impossible to reach all the affected demand centers. In this paper, a pre-disaster Humanitarian Logistics model is presented that jointly optimizes the prepositioning of aid distribution centers and the strengthening of road sections to ensure that as much affected population as possible can efficiently get help. The model is stochastic in nature and considers that the demand in the centers affected by the disaster and the state of the transportation network are random. Uncertainty is represented through scenarios representing possible disasters. The methodology is applied to a real-world case study based on the 2018 storm system that hit the Nampula Province in Mozambique.
Effect of Bridgehead Methyl Substituents on the Gas Permeability of Tröger’s-Base Derived Polymers of Intrinsic Microporosity
Authors: Malpass-Evans Richard , Rose Ian , Fuoco Alessio , Bernardo Paola , Clarizia Gabriele , McKeown Neil B. , Jansen Johannes C. , Carta Mariolino
Published: April 2020

A detailed comparison of the gas permeability of four Polymers of Intrinsic Microporosity containing Tröger’s base (TB-PIMs) is reported. In particular, we present the results of a systematic study of the differences between four related polymers, highlighting the importance of the role of methyl groups positioned at the bridgehead of ethanoanthracene (EA) and triptycene (Trip) components. The PIMs show BET surface areas between 845–1028 m2 g−1 and complete solubility in chloroform, which allowed for the casting of robust films that provided excellent permselectivities for O2/N2, CO2/N2, CO2/CH4 and H2/CH4 gas pairs so that some data surpass the 2008 Robeson upper bounds. Their interesting gas transport properties were mostly ascribed to a combination of high permeability and very strong size-selectivity of the polymers. Time lag measurements and determination of the gas diffusion coefficient of all polymers revealed that physical ageing strongly increased the size-selectivity, making them suitable for the preparation of thin film composite membranes.
Influence of the Natural Zeolite Particle Size Toward the Ammonia Adsorption Activity in Ceramic Hollow Fiber Membrane
Authors: Adam Mohd Ridhwan , Othman Mohd Hafiz Dzarfan , Sheikh Abdul Kadir Siti Hamimah , Mohd Sokri Mohd Nazri , Tai Zhong Sheng , Iwamoto Yuji , Tanemura Masaki , Honda Sawao , Puteh Mohd Hafiz , Rahman Mukhlis A. , Jaafar Juhana
Published: April 2020

Natural zeolite is widely used in removing ammonia via adsorption process because of its superior ion-exchange properties. Ceramic particle size affects the adsorptivity of particles toward ammonia. In this study, hollow fiber ceramic membrane (HFCM) was fabricated from natural zeolite via phase inversion. The effect of natural zeolite particle size toward the properties and performance of HFCM was evaluated. The results show that the HFCM with smaller particle sizes exhibited a more compact morphological structure with better mechanical strength. The adsorption performance of HFCM was significantly improved with smaller particle sizes because of longer residence time, as proven by the lower water permeability. A high adsorption performance of 96.67% was achieved for HFCM with the smallest particle size (36 μm). These findings provide a new perspective on the promising properties of the natural zeolite-derived HFCM for ammonia removal.
Experimental Investigation on the Wear and Damage Characteristics of Machined Wheel/Rail Materials under Dry Rolling-Sliding Condition
Authors: Liu Peijie , Quan Yanming , Wan Junjie , Yu Lang
Published: April 2020

To guarantee the smooth operation of trains, rail grinding and wheel turning are necessary practices to remove surface defects. Surface integrity of machined wheel/rail materials is significant to affect their tribological performance. In this paper, firstly, the wheel specimens were turned by a CNC lathe and the rail specimens were ground by a cylindrical grinding machine with various machining parameters. Then, the wear and damage behavior of the machined wheel/rail discs was systematically investigated via a twin-disc wear testing apparatus under dry rolling-sliding condition. The experimental results show that the surface hardness of rail discs after machining is slightly higher than that of wheel discs, while the surface roughness and plastic deformation layer of wheel discs are much larger than those of rail discs. The surface hardness increase degree of rail discs and their thickness of plastic deformation layer are greater than those of wheel discs after the rolling-sliding test. The wear loss of wheel discs is much larger than that of rail discs. Surface roughness, hardness and plastic deformation layer of wheel/rail discs after machining exert a comprehensive effect on the wear behavior, and friction pair with appropriate original surface hardness and roughness generates the smallest amount of wear loss.
Statistical Study for Leaching of Covellite in a Chloride Media
Authors: Pérez Kevin , Toro Norman , Saldaña Manuel , Salinas-Rodríguez Eleazar , Robles Pedro , Torres David , Jeldres Ricardo I.
Published: April 2020

Covellite is a secondary copper sulfide, and it is not abundant. There are few investigations on this mineral in spite of it being formed during the leaching of chalcocite or digenite; the other investigations on covellite are with the use of mineraloids, copper concentrates, and synthetic covellite. The present investigation applied the surface optimization methodology using a central composite face design to evaluate the effect of leaching time, chloride concentration, and sulfuric acid concentration on the level of copper extraction from covellite (84.3% of purity). Copper is dissolved from a sample of pure covellite without the application of temperature or pressure; the importance of its purity is that the behavior of the parameters is analyzed, isolating the impurities that affect leaching. The chloride came from NaCl, and it was effectuated in a size range from –150 to +106 μm. An ANOVA indicated that the leaching time and chloride concentration have the most significant influence, while the copper extraction was independent of sulfuric acid concentration. The experimental data were described by a highly representative quadratic model obtained by linear regression (R2 = 0.99).
Fabrication of Ultra-High Aspect Ratio (>420:1) Al2O3 Nanotube Arraysby Sidewall TransferMetal Assistant Chemical Etching
Authors: Li Hailiang , Xie Changqing
Published: April 2020

We report a robust, sidewall transfer metal assistant chemical etching scheme for fabricating Al2O3 nanotube arrays with an ultra-high aspect ratio. Electron beam lithography followed by low-temperature Au metal assisted chemical etching (MacEtch) is used to pattern high resolution, high aspect ratio, and vertical silicon nanostructures, used as a template. This template is subsequently transferred by an atomic layer deposition of the Al2O3 layer, followed by an annealing process, anisotropic dry etching of the Al2O3 layer, and a sacrificial silicon template. The process and characterization of the Al2O3 nanotube arrays are discussed in detail. Vertical Al2O3 nanotube arrays with line widths as small as 50 nm, heights of up to 21 μm, and aspect ratios up to 420:1 are fabricated on top of a silicon substrate. More importantly, such a sidewall transfer MacEtch approach is compatible with well-established silicon planar processes, and has the benefits of having a fully controllable linewidth and height, high reproducibility, and flexible design, making it attractive for a broad range of practical applications.
Investigation on the Tool Wear Suppression Mechanism in Non-Resonant Vibration-Assisted Micro Milling
Authors: Zheng Lu , Chen Wanqun , Huo Dehong
Published: April 2020

Excessive tool wear during hard and brittle material processing severely influences cutting performance. As one of the advanced machining technologies, vibration-assisted micro milling adds high-frequency small amplitude vibration on a micro milling tool or workpiece to improve cutting performance, especially for hard and brittle materials. In this paper, the tool wear suppression mechanism in non-resonant vibration-assisted micro milling is studied by using both finite element simulation and experiment methods. A finite element model of vibration-assisted micro milling using ABAQUS is developed based on the Johnson cook material and damage models. The tool-workpiece separation conditions are studied by considering the tool tip trajectories. The machining experiments are carried out on Ti-6Al-4V with a coated micro milling tool (fine-grain tungsten carbide substrate with ZrO2-BaCrO4 (ZB) coating) under different vibration frequencies (high, medium, and low) and cutting states (tool-workpiece separation or non-separation). The results show that tool wear can be reduced effectively in vibration-assisted micro milling due to different wear suppression mechanisms. The relationship between tool wear and cutting performance is studied, and the results indicate that besides tool wear reduction, better surface finish, lower burrs, and smaller chips can also be obtained as vibration assistance is added.
Silver Nanoprism Enhanced Colorimetry for Precise Detection of Dissolved Oxygen
Authors: Zuo Yunfeng , Chen Longfei , Hu Xuejia , Wang Fang , Yang Yi
Published: April 2020

Dissolved oxygen (DO) content is an essential indicator for evaluating the quality of the water body and the main parameter for water quality monitoring. The development of high-precision DO detection methods is of great significance. This paper reports an integrated optofluidic device for the high precision measurement of dissolved oxygen based on the characteristics of silver nanoprisms. Metal nanoparticles, especially silver nanoprisms, are extremely sensitive to their surroundings. In glucose and glucose oxidase systems, dissolved oxygen will be transformed into H2O2, which affects the oxidation and erosion process of nanoprisms, then influences the optical properties of nanoparticles. By detecting the shift in the plasma resonance peak of the silver nanoparticles, the dissolved oxygen (DO) content can be determined accurately. Great reconfigurability is one of the most significant advantages of the optofluidic device. By simply adjusting the flow rate ratio between the silver nanoprisms flow and the water sample flow, real-time continuous adjustment of the detection ranges of DO from 0 to 16 mg/L can be realized dynamically. The detection limit of this device is as low as 0.11 µM (3.52 µg/L) for DO measurement. Thus, the present optofluidic system has a wide range of potential applications in fields of biomedical analyses and water sensing.
Facile Production of a Fenton-Like Photocatalyst by Two-Step Calcination with a Broad pH Adaptability
Authors: Ji Siyang , Yang Yanling , Li Xing , Liu Hang , Zhou Zhiwei
Published: April 2020

A novel heterogeneous Fenton-like photocatalyst, Fe-doped graphitic carbon nitride (Fe-g-C3N4), was produced by facile two-step calcination method. This Fe–g–C3N4 catalyzed rhodamine B degradation in the presence of H2O2 accompanied with visible light irradiation. transmission electron microscopy(TEM), x-ray diffraction (XRD), FT-IR, x-ray photoelectron spectroscopy (XPS), and photoluminescence fluorescent spectrometer (PL) characterization analysis methods were adopted to evaluate the physicochemical property of samples. It can be observed that the Fe-g-C3N4 exhibited excellent photocatalytic Fenton-like activity at a wide pH range of 3–9, with rhodamine B(RhB) degradation efficiency up to 95.5% after irradiation for 45 min in the presence of 1.0 mM H2O2. Its high activity was ascribed to the formation of Fe–N ligands in the triazine rings that accelerated electron movement driving the Fe(III)/Fe(II) redox cycle, and inhibited photo-generated electron hole re-combinations for continuous generation of reactive oxygen species by reactions between Fe(II) and H2O2. The main active oxygen species were hydroxyl radicals, followed by superoxide radicals and hole electrons. This produced catalyst of Fe–g–C3N4 shows excellent reusability and stability, and can be a promising candidate for decontamination of wastewater.