bluuebunny/crossref_metadata_2025 huggingface dataset:
Extra Purified Exosomes from Human Placenta Contain an Unpredictable Small Number of Different Major Proteins
Authors: Burkova Evgeniya E. , Grigor’eva Alina E. , Bulgakov Dmitrii V. , Dmitrenok Pavel S. , Vlassov Valentin V. , Ryabchikova Elena I. , Sedykh Sergey E. , Nevinsky Georgy A.
Published: May 2019

Exosomes are nanovesicles (30–100 nm) containing various RNAs and different proteins. Exosomes are important in intracellular communication, immune function, etc. Exosomes from different sources including placenta were mainly obtained by different types of centrifugation and ultracentrifugations and were reported to contain from a few dozen to thousands of different proteins. First crude exosome preparations from four placentas (normal pregnancy) were obtained here using several standard centrifugations but then were additionally purified by gel filtration on Sepharose 4B. Individual preparations demonstrated different gel filtration profiles showing good or bad separation of exosome peaks from two peaks of impurity proteins and their complexes. According to electron microscopy, exosomes before gel filtration contain vesicles of different size, ring-shaped structures forming by ferritin and clusters of aggregated proteins and their complexes. After filtration through 220 nm filters and gel filtration exosomes display typically for exosome morphology and size (30–100 nm) and do not contain visible protein admixtures. Identification of exosome proteins was carried out by MS and MS/MS MALDI mass spectrometry of proteins’ tryptic hydrolyzates after their SDS-PAGE and 2D electrophoresis. We have obtained unexpected results. Good, purified exosomes contained only 11–13 different proteins: CD9, CD81, CD-63, hemoglobin subunits, interleukin-1 receptor, annexin A1, annexin A2, annexin A5, cytoplasmic actin, alkaline phosphatase, serotransferin, and probably human serum albumin and immunoglobulins. We assume that a possible number of exosome proteins found previously using crude preparations may be very much overestimated. Our data may be important for study of biological functions of pure exosomes.
Tamarixia radiata Behaviour Is Influenced by Volatiles from Both Plants and Diaphorina citri Nymphs
Authors: Liu Yan-Mei , Guo Shu-Hao , Wang Fei-Feng , Zhang Li-He , Guo Chang-Fei , Cuthbertson Andrew , Qiu Bao-Li , Sang Wen
Published: May 2019

Tamarixia radiata (Waterston) is an important ectoparasitoid of the Asian citrus psyllid, Diaphorina citri Kuwayama, a globally destructive pest of citrus. In the present study, a Y-tube olfactometer was employed to investigate whether the parasitoid T. radiata is capable of utilizing the odour source emitted by both plants and insect hosts during its foraging. The odour sources included Murraya paniculata (L.) shoots, 1st, 2nd, 3rd, 4th, and 5th D. citri instar nymphs, both individually and in combinations. Moreover, nymph-stage choice for parasitism, including 3rd, 4th, and 5th D. citri instar nymphs, was carried out. The results indicated that female T. radiata were only significantly attracted to volatiles emitted by M. paniculata shoots, 3rd, 4th, and 5th instar nymphs of D. citri, but could not distinguish between them. T. radiata males were not attracted by odours sourced from any instar D. citri nymphs. Female T. radiata adults exhibited a significant preference to later instar nymphal stages of D. citri for oviposition. The results from this study can be used to guide further investigations on the searching behaviour of this parasitoid and its utilization in D. citri biocontrol.
Influence of the Nutrients on the Biomass and Pigment Production of Chlorociboria aeruginascens
Authors: Stange Stephanie , Steudler Susanne , Delenk Hubertus , Werner Anett , Walther Thomas , Wagenführ André
Published: May 2019

The blue-green pigment xylindein, produced by the soft rot fungus Chlorociboria aeruginascens, is of considerable interest for various applications such as the veneer industry or organic semiconductors. The studies presented were performed in order to understand the fungal growth as well as the pigment production of C. aeruginascens. Therefore, various nutrient compositions were investigated. As a result, observations of the formation of xylindein through C. aeruginascens decoupling from growth were made. In the primary metabolism the uncolored biomass is formed. Various carbohydrates were determined as nutrients for the fungus and as a nitrogen source it was observed that the fungus prefers the complex organic nitrogen source, that being yeast extract. Furthermore, it was discovered that the ratio between carbohydrate and nitrogen sources encourages the switch of the metabolism and therewith the production of the blue-green pigment xylindein.
Structural, Magnetic and Electronic Properties of 3d Transition-Metal Atoms Adsorbed Monolayer BC2N: A First-principles Study
Authors: Chen Feng , Fan Li , Hou Xun , Li Chunmei , Chen Zhi-Qian
Published: May 2019

Based on the monolayer BC2N structure, the structural, electronic and magnetic properties of 3d transition metal (TM) atoms (V, Cr, Mn, Fe, Co and Ni) adsorbed on the monolayer BC2N, are studied by using the first principle method. The results show that 3d transition metal atoms are stably adsorbed on the monolayer BC2N. The most stable adsorption sites for V, Cr, and Mn atoms are the hollow adsorption site (H) of BC2N, while the other 3d TM atoms (Fe, Co, Ni) are more readily adsorbed above the C atoms (Tc). The majority of TM atoms are chemically adsorbed on BC2N, whereas Cr and Mn atoms are physically adsorbed on BC2N. Except for Ni, most 3d transition metal atoms can induce the monolayer BC2N magnetization, and the spin-charge density indicated that the magnetic moments of the adsorption systems are mainly concentrated on the TM atoms. Moreover, the introduction of TM atoms can modulate the electronic structure of a single layer of BC2N, making it advantageous for spintronic applications, and for the development of magnetic nanostructures.
A Glycosaminoglycan Extract from Portunus pelagicus Inhibits BACE1, the β Secretase Implicated in Alzheimer’s Disease
Authors: Mycroft-West Courtney J. , Cooper Lynsay C. , Devlin Anthony J. , Procter Patricia , Guimond Scott E. , Guerrini Marco , Fernig David G. , Lima Marcelo A. , Yates Edwin A. , Skidmore Mark A.
Published: May 2019

Therapeutic options for Alzheimer’s disease, the most common form of dementia, are currently restricted to palliative treatments. The glycosaminoglycan heparin, widely used as a clinical anticoagulant, has previously been shown to inhibit the Alzheimer’s disease-relevant β-secretase 1 (BACE1). Despite this, the deployment of pharmaceutical heparin for the treatment of Alzheimer’s disease is largely precluded by its potent anticoagulant activity. Furthermore, ongoing concerns regarding the use of mammalian-sourced heparins, primarily due to prion diseases and religious beliefs hinder the deployment of alternative heparin-based therapeutics. A marine-derived, heparan sulphate-containing glycosaminoglycan extract, isolated from the crab Portunus pelagicus, was identified to inhibit human BACE1 with comparable bioactivity to that of mammalian heparin (IC50 = 1.85 μg mL−1 (R2 = 0.94) and 2.43 μg mL−1 (R2 = 0.93), respectively), while possessing highly attenuated anticoagulant activities. The results from several structural techniques suggest that the interactions between BACE1 and the extract from P. pelagicus are complex and distinct from those of heparin.
Evaluation of Portal Vein Doppler Findings in Patients with Crimean–Congo Hemorrhagic Fever
Authors: Karavaş Erdal , Karakeçili Faruk
Published: May 2019

Background and objectives: In this study, we compare portal vein Doppler ultrasound (US) findings between patients with Crimean–Congo hemorrhagic fever (CCHF) and healthy persons and investigate the practicability of these findings in the prediction of disease severity. Materials and Methods: In this prospective study, portal vein Doppler US was performed in patients diagnosed with CCHF and healthy persons between March 2016 and May 2018. The patients were grouped according to mild-to-moderate and severe progression of CCHF. Liver size, portal vein diameter, portal vein flow rate, spleen volume, and splenic vein diameter were recorded in the patients and healthy controls. Results: Of the 48 patients diagnosed with CCHF, 25 were male. According to the scoring made, 38 patients were evaluated as having mild-to-moderate disease progression, and 10 were evaluated as having severe disease progression. With respect to the Doppler US findings, liver size, spleen volume, portal vein diameter, splenic vein diameter, and portal vein flow rate were significantly higher in the patient group compared with the controls. However, no significant difference was found in these parameters between the severe and mild-to-moderate progression groups. Conclusions: In the evaluation of and follow-up with patients with CCHF, portal vein Doppler US is a non-invasive and reliable tool for diagnosis.
The Influence of Dimerization on the Pharmacokinetics and Activity of an Antibacterial Enzyme Lysostaphin
Authors: Grishin Alexander V. , Lavrova Natalia V. , Lyashchuk Alexander M. , Strukova Natalia V. , Generalova Maria S. , Ryazanova Anna V. , Shestak Nikita V. , Boksha Irina S. , Polyakov Nikita B. , Galushkina Zoya M. , Soboleva Lyubov A. , Vetchinin Sergey S. , Pavlov Vitaliy M. , Karyagina Anna S. , Lunin Vladimir G.
Published: May 2019

The increasing prevalence of antibiotic-resistant strains of pathogenic bacteria is a major healthcare problem. Antibacterial lysins are enzymes that cleave the peptidoglycan of the bacterial cell wall. These proteins hold potential as a supplement or an alternative to traditional antibiotics since they are active against antibiotic resistant strains. However, antibacterial lysins are rapidly eliminated from the systemic circulation, which limits their application. Dimerization of an anti-pneumococcal lysin Cpl-1 has been demonstrated to decrease the clearance rate of this protein in mice. In the present work, we constructed a dimer of an anti-staphylococcal lysin lysostaphin by fusing it with an anti-parallel α-helical dimerization domain. Lysostaphin dimer had a more favorable pharmacokinetic profile with increased terminal half-life and area under the curve (AUC) values compared to monomeric lysostaphin. However, the staphylolytic activity of dimerized lysostaphin was decreased. This decrease in activity was likely caused by the dimerization; since the catalytic efficacy of lysostaphin dimer towards pentaglycine peptide was unaltered. Our results demonstrate that, although dimerization is indeed beneficial for the pharmacokinetics of antibacterial lysins, this approach might not be suitable for all lysins, as it can negatively affect the lysin activity.
High Production of Chitinolytic Activity in Halophilic Conditions by a New Marine Strain of Clonostachys rosea
Authors: Pasqualetti Marcella , Barghini Paolo , Giovannini Valeria , Fenice Massimiliano
Published: May 2019

Twenty-eight fungal strains have been isolated from different natural marine substrates and plate screened for their production of chitinolytic activity. The two apparent best producers, Trichoderma lixii IG127 and Clonostachys rosea IG119, were screened in shaken cultures in media containing 1% colloidal chitin, 1% yeast nitrogen base and 38‰ NaCl, for their ability to produce chitinolytic enzymes under halophilic conditions. In addition, they were tested for optimal growth conditions with respect to pH, salinity and temperature. The Trichoderma strain appeared to be a slight halotolerant fungus, while C. rosea IG119 clearly showed to be a halophilic marine fungus, its optimal growth conditions being very coherent for life in the marine environment (i.e., pH 8.0, salinity 38‰). Due to its high and relatively fast activity (258 U/L after 192 h of growth) accompanied by its halophilic behaviour (growth from 0 to 160‰ of salinity), C. rosea was selected for further studies. In view of possible industrial applications, its medium for chitinolytic enzyme production was optimized by Response Surface Methodology using 1% colloidal chitin and different concentrations of corn step liquor and yeast nitrogen base (0–0.5%). Time course of growth under optimized condition showed that maximum activity (394 U/L) was recorded after 120 h on medium containing Corn Steep Liquor 0.47% and Yeast Nitrogen Base 0.37%. Maximum of productivity (3.3 U/Lh) was recorded at the same incubation time. This was the first study that demonstrated high chitinolytic activity in a marine strain of C. rosea.
Antifungal Activities of 4″,6″-Disubstituted Amphiphilic Kanamycins
Authors: Alfindee Madher N. , Subedi Yagya P. , Grilley Michelle M. , Takemoto Jon Y. , Chang Cheng-Wei T.
Published: May 2019

Amphiphilic kanamycins derived from the classic antibiotic kanamycin have attracted interest due to their novel bioactivities beyond inhibition of bacteria. In this study, the recently described 4″,6″-diaryl amphiphilic kanamycins reported as inhibitors of connexin were examined for their antifungal activities. Nearly all 4″,6″-diaryl amphiphilic kanamycins tested had antifungal activities comparable to those of 4″,6″-dialkyl amphiphilic kanamycins, reported previously against several fungal strains. The minimal growth inhibitory concentrations (MICs) correlated with the degree of amphiphilicity (cLogD) of the di-substituted amphiphilic kanamycins. Using the fluorogenic dyes, SYTOXTM Green and propidium iodide, the most active compounds at the corresponding MICs or at 2×MICs caused biphasic dye fluorescence increases over time with intact cells. Further lowering the concentrations to half MICs caused first-order dye fluorescence increases. Interestingly, 4×MIC or 8×MIC levels resulted in fluorescence suppression that did not correlate with the MIC and plasma membrane permeabilization. The results show that 4″,6″-diaryl amphiphilic kanamycins are antifungal and that amphiphilicity parameter cLogD is useful for the design of the most membrane-active versions. A cautionary limitation of fluorescence suppression was revealed when using fluorogenic dyes to measure cell-permeation mechanisms with these antifungals at high concentrations. Finally, 4″,6″-diaryl amphiphilic kanamycins elevate the production of cellular reactive oxygen species as other reported amphiphilic kanamycins.
Epoxy–PCM Composites with Nanocarbons or Multidimensional Boron Nitride as Heat Flow Enhancers
Authors: Agrawal Richa , Hanna Joshua , Gunduz I. Emre , Luhrs Claudia C.
Published: May 2019

The need for affordable systems that are capable of regulating the temperature of living or storage spaces has increased the interest in exploring phase change materials (PCMs) for latent heat thermal energy storage (LHTES). This study investigates n-nonadecane (C19H40) and n-eicosane (C20H42) as alkane hydrocarbons/paraffins for LHTES applications. An epoxy resin is used as the support matrix medium to mitigate paraffin leakage, and a thickening agent is utilized to suppress phase separation during the curing process. In order to enhance the thermal conductivity of the epoxy–paraffin composite, conductive agents including carbon nanofibers (CNFs), carbon nanotubes (CNTs), boron nitride (BN) microparticles, or boron nitride nanotubes (BNNTs) are incorporated in different gravimetric ratios. Enhancements in latent heat, thermal conductivity, and heat transfer are realized with the addition of the thermal fillers. The sample composition with 10 wt.% BN shows excellent reversibility upon extended heating–cooling cycles and adequate viscosity for template casting as well as direct three-dimensional (3D) printing on fabrics, demonstrating the feasibility for facile integration onto liners/containers for thermal regulation purposes.
Active Pore-Edge Engineering of Single-Layer Niobium Diselenide Porous Nanosheets Electrode for Hydrogen Evolution
Authors: Wang Jianxing , Liu Xinyue , Liu Ying , Yang Guowei
Published: May 2019

Two-dimensional transition-metal dichalcogenides (TMDs) possess interesting catalytic properties for the electrochemical-assisted hydrogen-evolution reaction (HER). We used niobium diselenide (NbSe2) as a representative TMD, and prepared single-layer NbSe2 porous nanosheets (PNS) by a double-sonication liquid-phase exfoliation, with H2O2 as a pore-forming agent. The single-layer NbSe2 PNS were drop-cast on carbon foam (CF) to fabricate a three-dimensional robust NbSe2 PNS/CF electrode. The NbSe2 PNS/CF electrode exhibits a high current density of −50 mA cm−2 with an overpotential of 148 mV and a Tafel slope of 75.8 eV dec−1 for the HER process. Little deactivation is detected in continuous CV testing up to 20,000 cycles, which suggests that this novel NbSe2 PNS/CF is a promising catalytic electrode in the HER application. The porous structure of single-layer NbSe2 nanosheets can enhance the electrochemical performance compared with that of pore-free NbSe2 nanosheets. These findings illustrate that the single-layer NbSe2 PNS is a potential electrocatalytic material for HER. More importantly, the electrochemical performance of the NbSe2 PNS/CF expands the use of two-dimensional TMDs in electrocatalysis-related fields.
Internal R&D and Acquisition Performance of Chinese Pharmaceutical Firms: Moderation Effect of Acquisition Motive and Corporate Ownership
Authors: Yue Qi , Hua Xing , Li Jianyuan
Published: May 2019

Although corporate capability has been recognized as a key factor affecting corporate acquisition performance, the role of R&D capability in acquisition performance has not been fully explained. The aim of this paper was to research the impact of internal R&D on acquisition performance according to a sample of 215 acquisitions of Chinese listed pharmaceutical companies from 2012 to 2016. First, it was found that R&D has a significant negative effect on acquisition performance. Furthermore, it was confirmed that the acquisition motive and the ownership of the acquiring firm have a moderating effect on the relationship between R&D and acquisition performance. Compared to non-technical acquisitions, the negative effect of internal R&D on acquisition performance was reduced for technical acquisitions. Compared with non-state-owned-enterprise acquisition, the negative effect of internal R&D on the acquisition performance of state-owned enterprises was weakened. Our study enriches the research of the path dependence theory on the acquisition performance of enterprises and also the interpretation of acquisition performance on the basis of internal and external innovation and the institutional theory.
The ‘Anthropocene Proposal’: A Possible Quandary and A Work-Around
Authors: Bohle Martin , Bilham Nic
Published: May 2019

The debates about naming the unfolding times of anthropogenic global change the ‘Anthropocene’ are ultimately debates about the ‘human condition’. The proposal to amend the geological time scale by adding an ‘Anthropocene’ epoch (that is, the ‘Anthropocene proposal’ in its strict sense) is both an intra-geoscience debate about scientific sense-making and a debate about the societal context of the geosciences. This essay juxtaposes these debates, starting from three postulates: first, that the scientific methods of geological chronostratigraphy are applied rigorously; second, that anthropogenic global change is happening; and third, that the ‘Anthropocene proposal’ may be rejected if it does not meet the conditions required for its approval based on the rigorous application of the scientific methods of geological chronostratigraphy. These postulates are analysed through the lenses of the Cape Town Statement on Geoethics and the normative statements of the ‘geoethical promise’. It is found that an ethical quandary would arise if the ‘Anthropocene proposal’ were to be rejected. Consequently, and given the societal contexts of the geosciences, it is explored whether distinguishing between the geological past (as demarcated according to current chronostratigraphic methodology) and contemporary geological–historical times (characterised somewhat differently) could offer a work-around to tackle the quandary.
Introduction to “Religious Experience in the Hindu Tradition”
Authors: McDaniel June
Published: May 2019

This special issue of Religions brings together a talented group of international scholars who have studied and written on the Hindu tradition. The topic of religious experience is much debated in the field of Religious Studies, and here we present studies of Hindu religious experience explored from a variety of regions and perspectives. They are intended to show that religious experience has long been an important part of Hinduism, and we consider them to be important and relevant. As a body of scholarship, these articles refine our understanding of the range and variety of religious experience in Hinduism. In addition to their substantive contributions, the authors also show important new directions in the study of the third-largest religion in the world, with over one billion followers. This introduction will discuss some relevant issues in the field of Indology, some problems of language, and the difficulties faced in the study of religious experience. It will also give a brief sketch of the religious experiences described by our authors in some major types of Hinduism.
Rediscovering Old Gaul: Within or Beyond the Nation-State?
Authors: Ferlat Anne
Published: May 2019

Paganism is an umbrella term which, along with Wicca and various eclectic Pagan paths, encompasses European native faiths or, in other words, autochthonous pre-Christian religions. Thus at the intersection of Paganism and indigenous religions the contemporary return of European native faiths arguably constitutes an example of European indigenism on the model of autochthonous peoples’ liberation movements. This paper furthers my previous analysis which addressed the theme of European native faiths and ethnopsychiatry (Ferlat 2014), where I began to explore the idea that European native faiths might offer a route for healing traumas resulting from waves of acculturation which, throughout history, have undermined specific groups in Europe nowadays labelled “ethnocultural”. Such traumas are the object of study in ethnopsychiatry and cross-cultural psychology among people who face the consequences of violent acculturation. Considering the role played by the revitalization of cultures on other continents, I continue here my reflection about the way that European indigeneity and indigenism might be incarnated by European native faiths. I focus in particular on a reconstructionist Druidic group in France, the Druidic Assembly of the Oak and the Boar (ADCS). I introduce the concept of “internal colonialism” as an analytical tool to understand the meaning of one of its rituals which relates to Old Gaul and epitomizes a decolonizing stance. I conclude that the ADCS embodies a specific native project: an internal decolonization and peaceful indigenization process at work within a nation-state. However given a context where internal colonization is not officially recognized, the potential resilience of such a process remains uncertain.
Chronology of the 2014–2016 Eruptive Phase of Volcán de Colima and Volume Estimation of Associated Lava Flows and Pyroclastic Flows Based on Optical Multi-Sensors
Authors: Dávila Norma , Capra Lucia , Ferrés Dolors , Gavilanes-Ruiz Juan Carlos , Flores Pablo
Published: May 2019

The eruption at Volcán de Colima (México) on 10–11 July 2015 represents the most violent eruption that has occurred at this volcano since the 1913 Plinian eruption. The extraordinary runout of the associated pyroclastic flows was never observed during the past dome collapse events in 1991 or 2004–2005. Based on Satellite Pour l’Observation de la Terre (SPOT) and Earth Observing-1 (EO-1) ALI (Advanced Land Imager), the chronology of the different eruptive phases from September 2014 to September 2016 is reconstructed here. A digital image segmentation procedure allowed for the mapping of the trajectory of the lava flows emplaced on the main cone as well as the pyroclastic flow deposits that inundated the Montegrande ravine on the southern flank of the volcano. Digital surface models (DSMs) obtained from SPOT/6 dual-stereoscopic and tri-stereopair images were used to estimate the volumes of some lava flows and the main pyroclastic flow deposits. We estimated that the total volume of the magma that erupted during the 2014–2016 event was approximately 40 × 107 m3, which is one order of magnitude lower than that of the 1913 Plinian eruption. These data are fundamental for improving hazard assessment because the July 2015 eruption represents a unique scenario that has never before been observed at Volcán de Colima. Volume estimation provides complementary data to better understand eruptive processes, and detailed maps of the distributions of lava flows and pyroclastic flows represent fundamental tools for calibrating numerical modeling for hazard assessment. The stereo capabilities of the SPOT6/7 satellites for the detection of topographic changes and the and the availability of EO-1 ALI imagery are useful tools for reconstructing multitemporal eruptive events, even in areas that are not accessible due to ongoing eruptive activity.
Preparation and Characterization of Developed CuxSn1−xO2 Nanocomposite and Its Promising Methane Gas Sensing Properties
Authors: Shaalan Nagih , Hamad Dalia , Aljaafari Abdullah , Abdel-Latief Atta , Abdel-Rahim Mostafa
Published: May 2019

Novel materials with nanostructures are effective in controlling the physical properties needed for specific applications. The use of active and sensing materials is increasing in many applications, such as gas sensing. In the present work, we attempted to synthesize incorporated Cu2+ into the SnO2 matrix as CuxSn1−xO2 nanocomposite using a cost-effective precursor and method. It was observed that, at low concentrations of copper precursor, only SnO2 phase could be detected by X-ray diffraction (XRD). The distribution of Cu in the SnO2 matrix was further measured by elemental analysis of energy-dispersive X-ray (EDX) mapping and X-ray fluorescence (XRF). At high copper concentration, a separated monoclinic phase of CuO was formed (noted here as CuO/SnO2). The average crystallite size was slightly reduced from 5.9 nm to 4.7 nm with low doping of 0.00–5.00% Cu but increased up to 15.0 nm at high doping of 10.00% Cu upon the formation of separated SnO2 and CuO phases. The formation of Cu–SnO2 or CuO phases at low and high concentrations was also observed by photoluminescent spectra. Here, only the emission peak of SnO2 with a slight blueshift was recorded at low concentrations, while only the CuO emission peak was recorded at high concentration. The effect of Cu concentration on the sensing properties of SnO2 toward methane (CH4) gas was also investigated. It was found that the sensor embedded with 2.00% Cu exhibited an excellent sensitivity of 69.0 at 350 °C and a short response–recovery time compared with the other sensors reported here. The sensing mechanism of CuxSn1−xO2 and CuO/SnO2 is thus proposed based on Cu incorporation.
A Miniaturized Multiband Antenna Array for Robust Navigation in Aerial Applications
Authors: Caizzone Stefano , Buchner Georg , Circiu Mihaela-Simona , Cuntz Manuel , Elmarissi Wahid , Pérez Marcos Emilio
Published: May 2019

Satellite navigation is more and more important in a plethora of very different application fields, ranging from bank transactions to shipping, from autonomous driving to aerial applications, such as avionics as well as unmanned aerial vehicles (UAVs). Due to the increasing dependency on satellite navigation, the need for robust systems able to counteract unintentional or intentional interferences is growing. When considering interference-robust designs; however, the complexity increases. Top performance is obtained through the use of multi-antenna receivers capable of performing spatial nulling in the direction of the interference signals. In particular, mobile applications (aeronautics, UAVs, automotive) have a substantial interest in robust navigation, but they also have the strongest constraints on the weight and available places for installation, with the use of bigger and heavier systems posing a substantial problem. In order to overcome this limitation, the present work shows a miniaturized five element (4+1) antenna array, which operates at the L1/E1 band (with array capability), as well as at the L5/E5 band (as a single antenna). The proposed antenna array is able to fit into a 3.5-inch footprint, i.e., is compliant with the most widespread footprints for single antennas. Moreover, it is capable of multiband operation and meets the requirements of dual-frequency multi-constellation (DFMC) systems. Thanks to its extreme miniaturization and its compliance with current airborne single antenna footprints, the presented antenna array is suitable for easy integration in future aerial platforms, while enabling robustness and enhancing interference mitigation techniques using multi-antenna processing.
Preflight Spectral Calibration of Airborne Shortwave Infrared Hyperspectral Imager with Water Vapor Absorption Characteristics
Authors: Liu Honglin , Zhang Dong , Wang Yueming
Published: May 2019

Due to the strong absorption of water vapor at wavelengths of 1350–1420 nm and 1820–1940 nm, under normal atmospheric conditions, the actual digital number (DN) response curve of a hyperspectral imager deviates from the Gaussian shape, which leads to a decrease in the calibration accuracy of an instrument’s spectral response functions (SRF). The higher the calibration uncertainty of SRF, the worse the retrieval accuracy of the spectral characteristics of the targets. In this paper, an improved spectral calibration method based on a monochromator and the spectral absorptive characteristics of water vapor in the laboratory is presented. The water vapor spectral calibration method (WVSCM) uses the difference function to calculate the intrinsic DN response functions of the spectral channels located in the absorptive wavelength range of water vapor and corrects the wavelength offset of the monochromator via the least-square procedure to achieve spectral calibration throughout the full spectral responsive range of the hyper-spectrometer. The absolute spectral calibration uncertainty is ±0.125 nm. We validated the effectiveness of the WVSCM with two tunable semiconductor lasers, and the spectral wavelength positions calibrated by lasers and the WVSCM showed a good degree of consistency.
Fast Procedures for the Electrodeposition of Platinum Nanostructures on Miniaturized Electrodes for Improved Ion Sensing
Authors: Criscuolo Francesca , Taurino Irene , Dam Van , Catthoor Francky , Zevenbergen Marcel , Carrara Sandro , De Micheli Giovanni
Published: May 2019

Nanostructured materials have attracted considerable interest over the last few decades to enhance sensing capabilities thanks to their unique properties and large surface area. In particular, noble metal nanostructures offer several advantages including high stability, non-toxicity and excellent electrochemical behaviour. However, in recent years the great expansion of point-of-care (POC) and wearable systems and the attempt to perform measurements in tiny spaces have also risen the need of increasing sensors miniaturization. Fast constant potential electrodeposition techniques have been proven to be an efficient way to obtain conformal platinum and gold nanostructured layers on macro-electrodes. However, this technique is not effective on micro-electrodes. In this paper, we investigate an alternative one-step deposition technique of platinum nanoflowers on micro-electrodes by linear sweep voltammetry (LSV). The effective deposition of platinum nanoflowers with similar properties to the ones deposited on macro-electrodes is confirmed by morphological analysis and by the similar roughness factor (~200) and capacitance (~18 μ F/mm 2 ). The electrochemical behaviour of the nanostructured layer is then tested in an solid-contact (SC) L i + -selective micro-electrode and compared to the case of macro-electrodes. The sensor offers Nernstian calibration with same response time (~15 s) and a one-order of magnitude smaller limit of detection (LOD) ( 2.6 × 10 − 6 ) with respect to the macro-ion-selective sensors (ISE). Finally, sensor reversibility and stability in both wet and dry conditions is proven.
Unobtrusive Monitoring the Daily Activity Routine of Elderly People Living Alone, with Low-Cost Binary Sensors
Authors: Susnea Ioan , Dumitriu Luminita , Talmaciu Mihai , Pecheanu Emilia , Munteanu Dan
Published: May 2019

Most expert projections indicate that in 2030, there will be over one billion people aged 60 or over. The vast majority of them prefer to spend their last years at home, and almost a third of them live alone. This creates a growing need for technology-based solutions capable of helping older people to live independently in their places. Despite the wealth of solutions proposed for this general problem, there are very few support systems that can be reproduced on a larger scale. In this study, we propose a method to monitor the activity of the elderly living alone and detect deviations from the previous activity patterns based on the idea that the residential living environment can be modeled as a collection of behaviorally significant places located arbitrarily in a generic space. Then we use virtual pheromones—a concept defined in our previous work—to create images of the pheromone distribution maps, which describe the spatiotemporal evolution of the interactions between the user and the environment. We propose a method to detect deviations from the activity routines based on a simple statistical analysis of the resulting images. By applying this method on two public activity recognition datasets, we found that the system is capable of detecting both singular deviations and slow-deviating trends from the previous activity routine of the monitored persons.
Realization of Low Profile Leaky Wave Antennas Using the Bending Technique for Frequency Scanning and Sensor Applications
Authors: Kandwal Abhishek , Nie Zedong , Wang Lei , Liu Louis W. Y. , Das Ranjan
Published: May 2019

This paper proposes an efficient transmission line modulation by using the bending technique to realize low profile leaky wave antennas in the Ku-band for frequency scanning and sensor applications. The paper focuses mainly on the bending effects of the transmission line in terms of the sharpness of edges. The right-hand/left-hand transmission line can be designed in the form of zig-zag pattern with sharp corners and only the right-hand transmission line in the form of sinusoidal patterns with smooth corners. In this presentation, we demonstrate that transmission lines of this kind can be used to realize highly efficient leaky wave antennas with broadband impedance matching and high gain characteristics in the Ku-band. Dispersion analysis and ladder network analysis have been performed for investigating the performance of the proposed designs. The sharpness of the bends periodically distributed along the body of the antenna has been used to our advantage for frequency scanning in the left-hand and right-hand quadrants at different frequencies. The proposed bending technique has been proven to be instrumental in achieving the desired characteristics of low profile leaky wave antennas.
Using Random Forests on Real-World City Data for Urban Planning in a Visual Semantic Decision Support System
Authors: Sideris Nikolaos , Bardis Georgios , Voulodimos Athanasios , Miaoulis Georgios , Ghazanfarpour Djamchid
Published: May 2019

The constantly increasing amount and availability of urban data derived from varying sources leads to an assortment of challenges that include, among others, the consolidation, visualization, and maximal exploitation prospects of the aforementioned data. A preeminent problem affecting urban planning is the appropriate choice of location to host a particular activity (either commercial or common welfare service) or the correct use of an existing building or empty space. In this paper, we propose an approach to address these challenges availed with machine learning techniques. The proposed system combines, fuses, and merges various types of data from different sources, encodes them using a novel semantic model that can capture and utilize both low-level geometric information and higher level semantic information and subsequently feeds them to the random forests classifier, as well as other supervised machine learning models for comparisons. Our experimental evaluation on multiple real-world data sets comparing the performance of several classifiers (including Feedforward Neural Networks, Support Vector Machines, Bag of Decision Trees, k-Nearest Neighbors and Naïve Bayes), indicated the superiority of Random Forests in terms of the examined performance metrics (Accuracy, Specificity, Precision, Recall, F-measure and G-mean).
A Blind Spectrum Sensing Method Based on Deep Learning
Authors: Yang Kai , Huang Zhitao , Wang Xiang , Li Xueqiong
Published: May 2019

Spectrum sensing is one of the technologies that is used to solve the current problem of low utilization of spectrum resources. However, when the signal-to-noise ratio is low, current spectrum sensing methods cannot well-handle a situation in which the prior information of the licensed user signal is lacking. In this paper, a blind spectrum sensing method based on deep learning is proposed that uses three kinds of neural networks together, namely convolutional neural networks, long short-term memory, and fully connected neural networks. Experiments show that the proposed method has better performance than an energy detector, especially when the signal-to-noise ratio is low. At the same time, this paper also analyzes the effect of different long short-term memory layers on detection performance, and explores why the deep-learning-based detector can achieve better performance.
Ship Detection for Optical Remote Sensing Images Based on Visual Attention Enhanced Network
Authors: Bi Fukun , Hou Jinyuan , Chen Liang , Yang Zhihua , Wang Yanping
Published: May 2019

Ship detection plays a significant role in military and civil fields. Although some state-of-the-art detection methods, based on convolutional neural networks (CNN) have certain advantages, they still cannot solve the challenge well, including the large size of images, complex scene structure, a large amount of false alarm interference, and inshore ships. This paper proposes a ship detection method from optical remote sensing images, based on visual attention enhanced network. To effectively reduce false alarm in non-ship area and improve the detection efficiency from remote sensing images, we developed a light-weight local candidate scene network( L 2 CSN) to extract the local candidate scenes with ships. Then, for the selected local candidate scenes, we propose a ship detection method, based on the visual attention DSOD(VA-DSOD). Here, to enhance the detection performance and positioning accuracy of inshore ships, we both extract semantic features, based on DSOD and embed a visual attention enhanced network in DSOD to extract the visual features. We test the detection method on a large number of typical remote sensing datasets, which consist of Google Earth images and GaoFen-2 images. We regard the state-of-the-art method [sliding window DSOD (SW+DSOD)] as a baseline, which achieves the average precision (AP) of 82.33%. The AP of the proposed method increases by 7.53%. The detection and location performance of our proposed method outperforms the baseline in complex remote sensing scenes.
Online Spatial and Temporal Calibration for Monocular Direct Visual-Inertial Odometry
Authors: Feng Zheyu , Li Jianwen , Zhang Lundong , Chen Chen
Published: May 2019

Owing to the nonlinearity in visual-inertial state estimation, sufficiently accurate initial states, especially the spatial and temporal parameters between IMU (Inertial Measurement Unit) and camera, should be provided to avoid divergence. Moreover, these parameters are required to be calibrated online since they are likely to vary once the mechanical configuration slightly changes. Recently, direct approaches have gained popularity for their better performance than feature-based approaches in little-texture or low-illumination environments, taking advantage of tracking pixels directly. Based on these considerations, we perform a direct version of monocular VIO (Visual-inertial Odometry), and propose a novel approach to initialize the spatial-temporal parameters and estimate them with all other variables of interest (IMU pose, point inverse depth, etc.). We highlight that our approach is able to perform robust and accurate initialization and online calibration for the spatial and temporal parameters without utilizing any prior information, and also achieves high-precision estimates even when large temporal offset occurs. The performance of the proposed approach was verified through the public UAV (Unmanned Aerial Vehicle) dataset.
Insecticidal Activity of a Vip3Ab1 Chimera Is Conferred by Improved Protein Stability in the Midgut of Spodoptera eridania
Authors: Bowling Andrew J. , Sopko Megan S. , Tan Sek Yee , Larsen Cory M. , Pence Heather E. , Zack Marc D.
Published: May 2019

Vip3A proteins are important for the control of spodopteran pests in crops, including Spodoptera frugiperda (fall armyworm). Native Vip3Ab1 controls S. frugiperda, but it is ineffective against S. eridania (southern armyworm), a major pest of soybean in South America. Recently, a Vip3Ab1 chimera with a modified C-terminus was described, Vip3Ab1-740, which has increased potency against S. eridania while maintaining activity against S. frugiperda. As S. frugiperda and S. eridania are differentially susceptible to Vip3Ab1, experiments were conducted to identify and understand the mechanism by which this expanded potency is conferred. The role of protein stability, processing, and in vivo effects of Vip3Ab1 and Vip3Ab1-740 in both of these species was investigated. Biochemical characterization of the midgut fluids of these two species indicated no obvious differences in the composition and activity of digestive enzymes, which protease inhibitor studies indicated were likely serine proteases. Histological examination demonstrated that both proteins cause midgut disruption in S. frugiperda, while only Vip3Ab1-740 affects S. eridania. Immunolocalization indicated that both proteins were present in the midgut of S. frugiperda, but only Vip3Ab1-740 was detected in the midgut of S. eridania. We conclude that the gain of toxicity of Vip3Ab1-740 to S. eridania is due to an increase in protein stability in the midgut, which was conferred by C-terminal modification.
Armillifer Infections in Humans: A Systematic Review
Authors: Ioannou Petros , Vamvoukaki Rodanthi
Published: May 2019

Armillifer is a genus of obligate parasites belonging to the Pentastomida subclass that was first described as a cause of human disease in 1847. Human infection by Armillifer is rare and not widely known. These parasites are transmitted to humans by handling or eating undercooked meat from infected snakes, which are the definitive hosts, or oral uptake of environmental ova. The aim of this systematic review was to record all available evidence regarding infections by Armillifer in humans. A systematic review of PubMed (through 21 December 2018) for studies providing epidemiological, clinical, microbiological, as well as treatment data and outcomes of Armillifer infections was conducted. A total of 26 studies, containing data of 40 patients, were eventually included in the analysis. The most common sites of infection were the peritoneal cavity, the liver, the lower respiratory and the abdominal tract. The commonest infecting species was A. armillatus and most patients were asymptomatic; however, when symptoms occurred, the commonest was abdominal pain, even though unusual presentations occurred, such as hepatic encephalopathy or neurologic symptoms. Most cases were diagnosed at surgery or by imaging, and most patients were not treated. Mortality was low, but the majority of the cases with ocular infection lead to permanent loss of vision.
Diagnosis and Management of Fungal Neglected Tropical Diseases In Community Settings—Mycetoma and Sporotrichosis
Authors: Estrada-Castañón Roberto , Estrada-Chávez Guadalupe , Chávez-López María de Guadalupe
Published: May 2019

Background: This is a retrospective, analytic observational study where we describe cases of sporotrichosis and mycetoma from Acapulco General Hospital and Community Dermatology Mexico C.A. over 25 years. Analysis of environmental features that favour the development of such diseases has been made, as well as the limitations in the study and treatment of such diseases in resource poor settings. Methods: We reviewed the information on 76 sporotrichosis and 113 mycetoma patients out of a total of 14,000 consultations at Acapulco General Hospital and from Community Dermatology clinics. We analysed the epidemiological and mycological characteristics and the investigations used for diagnosis such as direct examination, culture, intradermal test reactions, and biopsy. Results: In total 91 confirmed cases of actinomycetoma, 22 of eumycetoma and 76 of sporotrichosis have been identified including diagnostic studies for both diseases and their treatment. Discussion: The results obtained have been analysed and interpreted in patients with mycetoma and sporotrichosis in the state of Guerrero, México, along with limitations in their management in areas with limited economic and logistical resources. The prevalence of mycetoma in our setting is compared with other centres where patients from all over the country are seen. The possible causes for variations in prevalence in specific areas has been looked for, in one of the poorest states of the Mexican Republic.
Reproductive Cycle of the Edible Sea Urchin Paracentrotus lividus (Echinodermata: Echinoidae) in the Aegean Sea
Authors: Vafidis Dimitris , Antoniadou Chryssanthi , Kyriakouli Kyratso
Published: May 2019

The sustainable management of fisheries resources requires extensive knowledge of their reproductive biology, which is scarcely the case for marine invertebrates. Sea urchins are among the most intensively harvested invertebrates, since their gonads, or “roe”, constitute a highly appreciated gastronomic delicacy, causing a severe decline in natural populations worldwide. In the Mediterranean, the typical commercial echinoid species is Paracentrotus lividus; its biology, however, has not been adequately studied in the Aegean Sea. Within this context, the present study examined the reproductive biology of the edible sea urchin, P. lividus, in the Aegean Sea (Pagasitikos Gulf) over a two-year period. Adult specimens were randomly collected by SCUBA diving (3–5 m) at monthly intervals to determine the gonad-somatic index, fecundity, and gametogenesis through the morphological and histological examination of the gonads. An annual reproductive cycle was defined in both years with a clear spawning peak in early spring, conforming to previous reports from other Mediterranean populations. A discrete secondary spawning period was also detected in early winter, as the species undergoes a second gametogenic event. These results are indicative for the increased reproductive potential of P. lividus in its south distributional range, suggesting a relevant revision of the official fishing season of the species.
A Fixed Point Theorem of the Hardy and Rogers Kind Endowed with Multiplicative Cone-C Class Functions
Authors: Ampadu Clement Boateng
Published: May 2019

In this paper we introduce the multiplicative version of cone-C class functions [1], and obtain some contraction mapping theorems of the Hardy and Rogers kind in multiplicative cone metric space endowed with such functions. Further, we propose some open problems that are publishable in nature.