bluuebunny/crossref_metadata_2025 huggingface dataset:
Cloning, Expression, and Characterization of a New Glycosaminoglycan Lyase from Microbacterium sp. H14
Authors: Sun Junhao , Han Xu , Song Guanrui , Gong Qianhong , Yu Wengong
Published: December 2019

Glycosaminoglycan (GAG) lyase is an effective tool for the structural and functional studies of glycosaminoglycans and preparation of functional oligosaccharides. A new GAG lyase from Microbacterium sp. H14 was cloned, expressed, purified, and characterized, with a molecular weight of approximately 85.9 kDa. The deduced lyase HCLaseM belonged to the polysaccharide lyase (PL) family 8. Based on the phylogenetic tree, HCLaseM could not be classified into the existing three subfamilies of this family. HCLaseM showed almost the same enzyme activity towards hyaluronan (HA), chondroitin sulfate A (CS-A), CS-B, CS-C, and CS-D, which was different from reported GAG lyases. HCLaseM exhibited the highest activities to both HA and CS-A at its optimal temperature (35 °C) and pH (pH 7.0). HCLaseM was stable in the range of pH 5.0–8.0 and temperature below 30 °C. The enzyme activity was independent of divalent metal ions and was not obviously affected by most metal ions. HCLaseM is an endo-type enzyme yielding unsaturated disaccharides as the end products. The facilitated diffusion effect of HCLaseM is dose-dependent in animal experiments. These properties make it a candidate for further basic research and application.
The Role of Cardiovascular and Metabolic Comorbidities in the Link between Atrial Fibrillation and Cognitive Impairment: An Appraisal of Current Scientific Evidence
Authors: AlTurki Ahmed , Maj Jakub B. , Marafi Mariam , Donato Filippo , Vescovo Giovanni , Russo Vincenzo , Proietti Riccardo
Published: December 2019

Atrial fibrillation (AF) is the most common arrhythmia encountered in clinical practice with implications on long-term outcomes. Metabolic disorders including diabetes mellitus and obesity are independent predictors of atrial fibrillation and present therapeutic targets to reduce both the incidence and duration burden of atrial fibrillation. The presence of pericardial fat in direct contact with cardiac structures, as well the subsequent release of proinflammatory cytokines, may play an important role in this connection. Atrial fibrillation is an independent predictor of cognitive impairment and dementia. While clinical stroke is a major contributor, other factors such as cerebral hypoperfusion and microbleeds play important roles. New evidence suggests that atrial fibrillation and cognitive impairment may be downstream events of atrial cardiomyopathy, which may be caused by several factors including metabolic syndrome, obesity, and obstructive sleep apnea. The mechanisms linking these comorbidities to cognitive impairment are not yet fully elucidated. A clearer understanding of the association of AF with dementia and cognitive impairment is imperative. Future studies should focus on the predictors of cognitive impairment among those with AF and aim to understand the potential mechanisms underlying these associations. This would inform strategies for the management of AF aiming to prevent continued cognitive impairment.
A Simple Derivation of the Birch–Murnaghan Equations of State (EOSs) and Comparison with EOSs Derived from Other Definitions of Finite Strain
Authors: Katsura Tomoo , Tange Yoshinori
Published: December 2019

Eulerian finite strain of an elastically isotropic body is defined using the expansion of squared length and the post-compression state as reference. The key to deriving second-, third- and fourth-order Birch–Murnaghan equations-of-state (EOSs) is not requiring a differential to describe the dimensions of a body owing to isotropic, uniform, and finite change in length and, therefore, volume. Truncation of higher orders of finite strain to express the Helmholtz free energy is not equal to ignoring higher-order pressure derivatives of the bulk modulus as zero. To better understand the Eulerian scheme, finite strain is defined by taking the pre-compressed state as the reference and EOSs are derived in both the Lagrangian and Eulerian schemes. In the Lagrangian scheme, pressure increases less significantly upon compression than the Eulerian scheme. Different Eulerian strains are defined by expansion of linear and cubed length and the first- and third-power Eulerian EOSs are derived in these schemes. Fitting analysis of pressure-scale-free data using these equations indicates that the Lagrangian scheme is inappropriate to describe P-V-T relations of MgO, whereas three Eulerian EOSs including the Birch–Murnaghan EOS have equivalent significance.
Green Synthesis and Electrochemical Properties of Mono- and Dimers Derived from Phenylaminoisoquinolinequinones
Authors: Ibacache Juana Andrea , Valderrama Jaime A. , Faúndes Judith , Danimann Alex , Recio Francisco J. , Zúñiga César A.
Published: December 2019

In the search for new quinoid compounds endowed with potential anticancer activity, the synthesis of novel heterodimers containing the cytotoxic 7-phenylaminoisoquinolinequinone and 2-phenylaminonaphthoquinone pharmacophores, connected through methylene and ethylene spacers, is reported. The heterodimers were prepared from their respective isoquinoline and naphthoquinones and 4,4′-diaminodiphenyl alkenes. The access to the target heterodimers and their corresponding monomers was performed both through oxidative amination reactions assisted by ultrasound and CeCl3·7H2O catalysis “in water”. This eco-friendly procedure was successfully extended to the one-pot synthesis of homodimers derived from the 7-phenylaminoisoquinolinequinone pharmacophore. The electrochemical properties of the monomers and dimers were determined by cyclic and square wave voltammetry. The number of electrons transferred during the oxidation process, associated to the redox potential EI1/2, was determined by controlled potential coulometry.
Neuroprotective Norsesquiterpenoids and Triterpenoids from Populus euphratica Resins
Authors: Liu Yun-Yun , Huang Dan-Ling , Dong Yun , Qin Da-Peng , Yan Yong-Ming , Cheng Yong-Xian
Published: December 2019

Two new octanorlanostane-type triterpenes, euphraticanoids A and B (1 and 2), two new trinorsesquiterpenoids, euphraticanoids C and D (3 and 4), and eight known triterpenoids (5, 6, 8–13) along with one steroid (7) were isolated from Populus euphratica resins. The structures of these new compounds, including their absolute configurations, were characterized by spectrocsopic, chemical, and computational methods. Biological evaluation revealed that compounds 4, 7–9, 12, and 13 display neuroprotective activities in H2O2-induced HT-22 cells with 4, 8, and 9 occurring in a concentration-dependent manner and 7, 12, and 13 reaching the maximum effects at 20 μM. Meanwhile, the neuroprotective properties of all isolates were accessed using glutamate-induced SH-SY5Y cells and disclosed that compounds 3, 4, 8, and 9 could dose-dependently protect neural cell injury in a concentration range of 10–40 μM. Finally, a brief structure–activity relationship was briefly discussed.
Tetrandrine Interaction with ABCB1 Reverses Multidrug Resistance in Cancer Cells Through Competition with Anti-Cancer Drugs Followed by Downregulation of ABCB1 Expression
Authors: Liao Dan , Zhang Wei , Gupta Pranav , Lei Zi-Ning , Wang Jing-Quan , Cai Chao-Yun , Vera Albert A. De , Zhang Lei , Chen Zhe-Sheng , Yang Dong-Hua
Published: December 2019

The overexpression of ABC transporters induced by anticancer drugs has been found to be the main cause of multidrug resistance. It is actually also a strategy by which cancer cells escape being killed. Tetrandrine is a natural product extracted from the stem of Tinospora crispa. In this study, tetrandrine showed synergistic cytotoxic activity in combinational use with chemotherapeutic drugs, such as Doxorubicin, Vincristine, and Paclitaxel, in both drug-induced and MDR1 gene-transfected cancer cells that over-expressed ABCB1/P-glycoprotein. Tetrandrine stimulated P-glycoprotein ATPase activity, decreased the efflux of [3H]-Paclitaxel and increased the intracellular accumulation of [3H]-Paclitaxel in KB-C2 cells. Furthermore, SW620/Ad300 and KB-C2 cells pretreated with 1 μM tetrandrine for 72 h decreased P-glycoprotein expression without changing its cellular localization. This was demonstrated through Western blotting and immunofluorescence analysis. Interestingly, down-regulation of P-glycoprotein expression was not correlated with gene transcription, as the MDR1 mRNA level exhibited a slight fluctuation in SW620/Ad300 and KB-C2 cells at 0, 24, 48, and 72 h treatment time points. In addition, molecular docking analysis predicted that tetrandrine had inhibitory potential with the ABCB1 transporter. Our results suggested that tetrandrine can antagonize MDR in both drug-selected and MDR1 gene-transfected cancer cells by down regulating the expression of the ABCB1 transporter, followed by increasing the intracellular concentration of chemotherapeutic agents. The combinational therapy using tetrandrine and other anticancer drugs could promote the treatment efficiency of drugs that are substrates of ABCB1.
The Hydrophobicity of Lignocellulosic Fiber Network Can Be Enhanced with Suberin Fatty Acids
Authors: Korpinen Risto I. , Kilpeläinen Petri , Sarjala Tytti , Nurmi Maristiina , Saloranta Pauliina , Holmbom Thomas , Koivula Hanna , Mikkonen Kirsi S. , Willför Stefan , Saranpää Pekka T.
Published: December 2019

Suberin fatty acids were extracted from outer bark of Silver birch (Betula pendula Roth.) using an isopropanolic sodium hydroxide solution. Laboratory sheets composed of lignocellulosic fiber networks were prepared from unbleached and unrefined softwood kraft pulp and further impregnated with suberin fatty acid monomers and cured with maleic anhydride in ethanol solution. The treatment resulted in hydrophobic surfaces, in which the contact angles remained over 120 degrees during the entire measurement. The fiber network also retained its water vapor permeability and enhanced fiber–fiber bonding resulted in improved tensile strength of the sheets. Scanning electron microscopy (SEM) images revealed that the curing agent, together with suberin fatty acids, was evenly distributed on the fiber surfaces and smoothing occurred over the wrinkled microfibrillar structure. High concentrations of the curing agent resulted in globular structures containing betulinol derivates as revealed with time-of-flight secondary ion mass spectrometry (ToF-SIMS). Also, the larger amount of suberin fatty acid monomers slightly impaired the optical properties of sheets.
The Impact of Herbs and Spices on Increasing the Appreciation and Intake of Low-Salt Legume-Based Meals
Authors: Dougkas Anestis , Vannereux Marine , Giboreau Agnès
Published: December 2019

Flavoring using blends of herbs and spices (H&S) instead of salt may be a promising approach to increase legume consumption and reduce salt content in foods. This study examines the effects of H&S on the appreciation and intake of low-salt legume-based dishes in a real ecological eating environment. Four mezzes with standard (0.8% w/w) (S) or lower (0.4% w/w) (LS) salt level and with or without H&S (LSHS, SHS) were developed. In a randomized cross-over trial, 94 participants attended four sessions, one week apart and received the four variants as a starter during lunch. Overall liking, food intake, and appetite ratings (visual analogue scale, VAS) were assessed during lunch. A follow-up study (n = 130) was performed where the four variants were evaluated, and overall liking was measured at the same session. Overall liking and taste scores of SHS were significantly higher compared with LS (p = 0.04 and p = 0.03, respectively), but there were no significant differences between LSHS and S. However, there were no differences in energy intake or in appetite ratings among the products. Overall appreciation was similar between the low-salt with H&S and the standard-salt mezze, suggesting that the addition of H&S is a feasible strategy for achieving a 50% reduction in salt content without compromising hedonic appreciation.
Combined Treatment with Omega-3 Fatty Acid and Cholecalciferol Increases 1,25-Dihydroxyvitamin D Levels by Modulating Dysregulation of Vitamin D Metabolism in 5/6 Nephrectomy Rats
Authors: Lee Su Mi , Lee Mi Hwa , Son Young Ki , Kim Seong Eun , An Won Suk
Published: December 2019

The protein 1α-hydroxylase (CYP27B1) was expressed in liver and omega-3 fatty acid (FA) elevated 1,25-dihydroxyvitamin D [1,25(OH)2D] levels in dialysis patients. The aim of this study was to determine whether omega-3 FA and cholecalciferol have effects on vitamin D metabolism related to CYP27B1 and 24-hydroxylase (CYP24) activities in the kidney and liver of 5/6 nephrectomy (Nx) rats. Male Sprague–Dawley rats were divided into the following groups: sham control, 5/6 Nx, 5/6 Nx treated with cholecalciferol, 5/6 Nx treated with omega-3 FA, and 5/6 Nx treated with cholecalciferol/omega-3 FA. CYP27B1 and CYP24 expression were measured in the liver and kidney. Further, 1,25(OH)2D and 25-hydroxyvitamin D [25(OH)D] levels were measured in serum. Among Nx groups, 1,25(OH)2D and 25(OH)D levels were lowest in the 5/6 Nx group. CYP24 expression was increased in the kidney of the 5/6 Nx rat model, which was found to be reversed by omega-3 FA or cholecalciferol/omega-3 FA supplementation. Decreased CYP27B1 expression was observed in the liver of the 5/6 Nx rats and its expression was recovered by supplementation with cholecalciferol/omega-3 FA. In conclusion, omega-3 FA and cholecalciferol may synergistically increase 1,25(OH)2D levels by inhibiting CYP24 expression in the kidney and liver and activating CYP27B1 expression in the liver of 5/6 Nx rats.
Food Sources of Potassium in the Average Polish Diet
Authors: Górska-Warsewicz Hanna , Rejman Krystyna , Laskowski Wacław , Kowalcze Katarzyna
Published: December 2019

The aim of this study was to identify the food sources of potassium in the average Polish diet based on the data from the 2016 Household Budget Survey conducted on the representative sample of the Polish population (36,886 households, n = 99,230). This survey is organized by the Central Statistical Office and is related to the expenditures, quantitative consumption and revenues in households. We analyzed 91 sub-groups (i.e., milk, red meat) from 13 food categories (i.e., milk and dairy products, meat and products). Our findings indicated that the daily supply of potassium in the average Polish diet was 2617.9 mg, which meant covering the average allowance in 83%. Vegetables provided 32.5% of potassium, of which potatoes accounted for 16.2% of supply, and other vegetables for 16.2%. Tomatoes as well as other vegetables and mushrooms provided a total of 8.2% of potassium among vegetables. The next position was taken by the meat and meat products category (17.7%), with the largest share of meat products (6.7%) and red meat (5.2%). Cereal products supplied 16.64% of potassium, of which bread, rolls and bread products (12.2%) were of the greatest importance. Milk and dairy products turned out to be the fourth product category as a source of potassium (11.9%), with the highest share of milk (6.8%) and yoghurts and milk drinks (3.9%).
Libidibia ferrea (jucá), a Traditional Anti-Inflammatory: A Study of Acute Toxicity in Adult and Embryos Zebrafish (Danio rerio)
Authors: Ferreira Diego Q. , Ferraz Thamara O. , Araújo Raquel S. , Cruz Rodrigo Alves Souza , Fernandes Caio Pinho , Souza Gisele C. , Ortiz Brenda L. S. , Sarquis Rosangela S. F. R. , Miranda Jemima C. M. M. , Garrett Rafael , Carvalho José C. Tavares , Oliveira Anna Eliza M. de Faria Mota
Published: December 2019

The plant species Libidibia ferrea (Mart. ex Tul.) LP Queiroz var. ferrea basionym of Caesalpinia ferrea (Mart. ex Tul.) is used in various regions of Brazil in folk medicine in the treatment of several health problems, especially in acute and chronic inflammatory processes. Most of the preparations employed are alcoholic. Therefore, this study aimed to evaluate the acute toxicity of the hydroethanolic extract of fruits of Libidibia ferrea (EHEFLf) in zebrafish, emphasizing the possible changes in the organic-cellular level of the gills, liver, kidneys, and intestine and on embryos. The result obtained by LC-M/MS from EHEFLf indicated a high concentration of possible polyhydroxylated substances. EHEFLf, at a dose of 2 g/kg orally, produced non-significant alterations of the analyzed organs. However, for embryos, the treatment with different concentrations demonstrated heart toxicity that was concentration-dependent. There is no evidence of a correlation of the observed effects with the phytochemical composition, and considering the species of animal used, it can be suggested that the oral use of L. ferrea hydroethanolic extract has an acceptable degree of safety for use as an oral medicinal product. and embryo results have shown significant affinity to the heart; however, it is perceived to be related to the concentrations used.
Mechanistic Evaluation of Enhanced Curcumin Delivery through Human Skin In Vitro from Optimised Nanoemulsion Formulations Fabricated with Different Penetration Enhancers
Authors: Yousef Shereen A. , Mohammed Yousuf H. , Namjoshi Sarika , Grice Jeffrey E. , Benson Heather A. E. , Sakran Wedad , Roberts Michael S.
Published: December 2019

Curcumin is a natural product with chemopreventive and other properties that are potentially useful in treating skin diseases, including psoriasis and melanoma. However, because of the excellent barrier function of the stratum corneum and the relatively high lipophilicity of curcumin (log P 3.6), skin delivery of curcumin is challenging. We used the principles of a Quality by Design (QbD) approach to develop nanoemulsion formulations containing biocompatible components, including Labrasol and Lecithin as surfactants and Transcutol and ethanol as cosurfactants, to enhance the skin delivery of curcumin. The nanoemulsions were characterised by cryo-SEM, Zeta potential, droplet size, pH, electrical conductivity (EC) and viscosity (η). Physicochemical long-term stability (6 months) was also investigated. The mean droplet sizes as determined by dynamic light scattering (DLS) were in the lower submicron range (20–50 nm) and the average Zeta potential values were low (range: −0.12 to −2.98 mV). Newtonian flow was suggested for the nanoemulsions investigated, with dynamic viscosity of the nanoemulsion formulations ranging from 5.8 to 31 cP. The droplet size of curcumin loaded formulations remained largely constant over a 6-month storage period. The inclusion of terpenes to further enhance skin permeation was also examined. All nanoemulsions significantly enhanced the permeation of curcumin through heat-separated human epidermal membranes, with the greatest effect being a 28-fold increase in maximum flux (Jmax) achieved with a limonene-based nanoemulsion, compared to a 60% ethanol in water control vehicle. The increases in curcumin flux were associated with increased skin diffusivity. In summary, we demonstrated the effectiveness of nanoemulsions for the skin delivery of the lipophilic active compound curcumin, and elucidated the mechanism of permeation enhancement. These formulations show promise as delivery vehicles for curcumin to target psoriasis and skin cancer, and more broadly for other skin delivery applications.
Polypharmacy and Pharmacological Treatment of Diabetes in Older Individuals: A Population-Based Study in Quebec, Canada
Authors: Gagnon Marie-Eve , Sirois Caroline , Simard Marc , Plante Céline
Published: December 2019

Our objectives were to describe the use of pharmacological treatments in older adults with diabetes and to identify the factors associated with the use of a combination of hypoglycemic, antihypertensive and lipid-lowering agents. Using the Quebec Integrated Chronic Disease Surveillance System, we conducted a population-based cohort study among individuals aged 66–75 years with diabetes in 2014–2015. We described the number of medications and the classes of medications used and calculated the proportion of individuals using at least one medication from each of these classes: hypoglycemics, antihypertensives and lipid-lowering agents. We identified the factors associated with the use of this combination of treatments by performing robust Poisson regressions. The 146,710 individuals used an average of 12 (SD 7) different medications, mostly cardiovascular (91.3% of users), hormones, including hypoglycemic agents (84.5%), and central nervous system medications (79.8%). The majority of individuals (59%) were exposed to the combination of treatments and the factor most strongly associated was the presence of cardiovascular comorbidities (RR: 1.29; 99% CI: 1.28–1.31). Older individuals with diabetes are exposed to a large number of medications. While the use of the combination of treatments is significant and could translate into cardiovascular benefits at the population level, the potential risk associated with polypharmacy needs to be documented.
An Alginate Hybrid Sponge with High Thermal Stability: Its Flame Retardant Properties and Mechanism
Authors: Jiang Yuhuan , Pang Xuening , Deng Yujia , Sun Xiaolu , Zhao Xihui , Xu Peng , Shao Peiyuan , Zhang Lei , Li Qun , Li Zichao
Published: December 2019

The worldwide applications of polyurethane (PU) and polystyrene (PS) sponge materials have been causing massive non-renewable resource consumption and huge loss of property and life due to its high flammability. Finding a biodegradable and regenerative sponge material with desirable thermal and flame retardant properties remains challenging to date. In this study, bio-based, renewable calcium alginate hybrid sponge materials (CAS) with high thermal stability and flame retardancy were fabricated through a simple, eco-friendly, in situ, chemical-foaming process at room temperature, followed by a facile and economical post-cross-linking method to obtain the organic-inorganic (CaCO3) hybrid materials. The microstructure of CAS showed desirable porous networks with a porosity rate of 70.3%, indicating that a great amount of raw materials can be saved to achieve remarkable cost control. The sponge materials reached a limiting oxygen index (LOI) of 39, which was greatly improved compared with common sponge. Moreover, with only 5% calcium carbonate content, the initial thermal degradation temperature of CAS was increased by 70 °C (from 150 to 220 °C), compared to that of calcium alginate, which met the requirements of high-temperature resistant and nonflammable materials. The thermal degradation mechanism of CAS was supposed based on the experimental data. The combined results suggest promising prospects for the application of CAS in a range of fields and the sponge materials provide an alternative for the commonly used PU and PS sponge materials.
Toughened High-Flow Polypropylene with Polyolefin-Based Elastomers
Authors: Wang Xiong , Hu Sheng , Guo Yi , Li Guangquan , Xu Renwei
Published: December 2019

Polyolefin is the most widely used and versatile commodity polymer. In this work, three types of polyolefin-based elastomers (PBEs) were adopted to toughen a high-flow polypropylene to improve its overall performance. The chain microstructures of these PBEs, including ethylene/1-octene (E/O) random copolymer from Dow Chemical′s polyolefin elastomer (POE), olefin block copolymers (OBCs) of E/O from Dow, and ethylene/propylene random copolymer from ExxonMobil’s propylene-based elastomer, were elucidated by GPC, 13C NMR, TREF, and DSC techniques. The mechanical, thermal and optical properties, and morphology analysis of the PP/PBE blends were also studied to investigate the toughening mechanism of these PBEs. The results showed that all three types of PBEs can effectively improve the Izod impact strength of the PP/PBE blends by the addition of the rubber compositions, at the cost of the stiffness. PBE-1 and PBE-2 were found to have a great stiffness–toughness balance with about 1700 MPa of flexural modulus, about 110 °C of HDT and 3.6 kJ/m2 of impact strength on the prepared PP/PBE blends by forming separated rubber phase and refined spherulite crystals. As a result, the OBC with alternating hard and soft segments could achieve a similar toughening effect as the E/P random copolymer. Surprisingly, no obvious rubber phase separation was observed in the PP/PBE-4 blend, which might be due to the good compatibility of the E/P random chains with the isotactic PP; therefore, the PP/PBE blend obtains great toughness performance and optical transparency with the highest Izod impact strength of 4.2 kJ/m2 and excellent transparency.
Screwdriver Aspiration During Oral Procedures: A Lesson for Dentists and Gastroenterologists
Authors: Iovino Paola , Di Sarno Alessandro , De Caro Vincenzo , Mazzei Cosimo , Santonicola Antonella , Bruno Vincenzo
Published: December 2019

This article reports the case of a patient suffering from Alzheimer’s disease who underwent a dental procedure for the peri-implantitis of his dental implants placed some years earlier. Our aim was to describe a misinterpreted accidental foreign body aspiration and its management. Due to an involuntary movement, the patient accidentally ingested a screwdriver, so, although asymptomatic, he was taken to the hospital. Based on the radiographic interpretation, the radiologists diagnosed the presence of the object in the distal esophagus; an esophagogastroduodenoscopy was performed but the screwdriver was not found. Subsequently, a computed tomography (CT) scan was performed which placed the foreign body in the airways and it was successfully removed by bronchoscopy. Patients with dementia need additional care during dental procedures because of the increased risk of ingestion and/or aspiration. We demonstrated how important it is, even without any symptoms, the need to be vigilant in seeking out urgent care as soon as possible.
Melting Layer Detection and Characterization based on Range Height Indicator–Quasi Vertical Profiles
Authors: Allabakash Shaik , Lim Sanghun , Jang Bong-Joo
Published: December 2019

The melting layer (ML) is an important region used to describe the transition of hydrometeors from the solid to the liquid phase. It is a typical feature used to characterize the vertical structure of the stratiform precipitation. The present study implements a new automatic melting-layer detection algorithm based on the range-height-indicator–quasi-vertical profile (R-QVP) in the X-band dual-polarization radars. The algorithm uses the gradients of the polarimetric radar variables reflectivity factor at horizontal polarization (Zh), differential reflectivity (Zdr), and copolar correlation coefficient (ρhv), and their combinations to describe the ML characteristics. The melting layer heights derived from the radar were compared and validated with the heights of the 0 °C wet-bulb temperature derived from the Modern-Era retrospective analysis for research and applications (MERRA) reanalysis datasets and obtained high correlation coefficient 0.96. The R-QVP combined with this algorithm led to spatial and temporal variabilities of the melting layer thickness. The thickness of the melting layer was independent of the seasonal, spatial, and temporal variabilities of the precipitations. Intriguing polarimetric signatures have been observed inside, above, and below the ML, based on the phase of the precipitation particles. The statistics of the polarimetric variables were evaluated for ML, rain, and snow. Further, the linkage between enhanced specific differential phase shift (Kdp) and Zdr in the dendritic growth layer (DGL) and surface precipitation was also described.
Deriving Particulate Organic Carbon in Coastal Waters from Remote Sensing: Inter-Comparison Exercise and Development of a Maximum Band-Ratio Approach
Authors: Tran Trung Kien , Duforêt-Gaurier Lucile , Vantrepotte Vincent , Jorge Daniel Schaffer Ferreira , Mériaux Xavier , Cauvin Arnaud , Fanton d’Andon Odile , Loisel Hubert
Published: December 2019

Recently, different algorithms have been developed to assess near-surface particulate organic matter (POC) concentration over coastal waters. In this study, we gathered an extensive in situ dataset representing various contrasted bio-optical coastal environments at low, medium, and high latitudes, with various bulk particulate matter chemical compositions (mineral-dominated, 50% of the data set, mixed, 40%, or organic-dominated, 10%). The dataset includes 606 coincident measurements of POC concentration and remote-sensing reflectance, Rrs, with POC concentrations covering three orders of magnitude. Twelve existing algorithms have then been tested on this data set, and a new one was proposed. The results show that the performance of historical algorithms depends on the type of water, with an overall low performance observed for mineral-dominated waters. Furthermore, none of the tested algorithms provided satisfactory results over the whole POC range. A novel approach was thus developed based on a maximum band ratio of Rrs (red/blue, red/yellow or red/green ratio). Based on the standard statistical metric for the evaluation of inverse models, the new algorithm presents the best performance. The root-mean square deviation for log-transformed data (RMSDlog) is 0.25. The mean absolute percentage difference (MAPD) is 37.48%. The mean bias (MB) and median ratio (MR) values are 0.54 μg L−1 and 1.02, respectively. This algorithm replicates quite well the distribution of in situ data. The new algorithm was also tested on a matchup dataset gathering 154 coincident MERIS (MEdium Resolution Imaging Spectrometer) Rrs and in situ POC concentration sampled along the French coast. The matchup analysis showed that the performance of the new algorithm is satisfactory (RMSDlog = 0.24, MAPD = 34.16%, MR = 0.92). A regional illustration of the model performance for the Louisiana continental shelf shows that monthly mean POC concentrations derived from MERIS with the new algorithm are consistent with those derived from the 2016 algorithm of Le et al. which was specifically developed for this region.
Estimation of the Antenna Phase Center Correction Model for the BeiDou-3 MEO Satellites
Authors: Yan Xingyuan , Huang Guanwen , Zhang Qin , Wang Le , Qin Zhiwei , Xie Shichao
Published: December 2019

Satellite antenna phase center offsets (PCOs) and phase variations (PVs) for BeiDou-3 satellites are estimated based on the tracking data of the Multi-GNSS Experiment (MGEX) and the international GNSS Monitoring and Assessment System (iGMAS) network. However, when estimating the (PCOs) of BeiDou-3 medium Earth orbit (MEO) satellites by pure Extending the CODE Orbit Model (ECOM1), the x-offset estimations of the PCOs have a systematic variation of about 0.4 m with the elevation of the Sun above the orbital plane (β-angle). Thus, a priori box-wing solar radiation pressure (SRP) model of BeiDou-3 MEO was assisted with ECOM1. Then, the satellite type-specific PCOs and common PVs were obtained. The estimations of PCOs and PVs were compared with the MGEX PCOs from the precise orbit and clock offset. When the MGEX PCOs were used, the root mean square (RMS) of 24 h overlap was 6.76, 4.36, 1.46 cm, in along-track, cross-track, and radial directions, respectively; the RMS and standard deviations (STD) of the 24 h clock offset overlap were 0.28 and 0.15 ns; the fitting RMS of the 72 h clock offset of the quadratic polynomial was 0.243 ns. After comparing this with the estimated PCOs and PVs, the RMS of the 24 h orbit overlap was decreased by 6.5 mm (10.54%), 1.8 mm (4.4%), and 1.1 mm (8.03%) in the along-track, cross-track, and radial directions, respectively; the RMS and STD of the 24 h clock offset overlap were decreased by 0.024 ns (8.6%) and 0.020 ns (13.1%), respectively; the fitting RMS of the 72 h clock offset of the quadratic polynomial was reduced by about 0.016 ns (6.5%).
Hyperspectral Image Super-Resolution with 1D–2D Attentional Convolutional Neural Network
Authors: Li Jiaojiao , Cui Ruxing , Li Bo , Song Rui , Li Yunsong , Du Qian
Published: December 2019

Hyperspectral image (HSI) super-resolution (SR) is of great application value and has attracted broad attention. The hyperspectral single image super-resolution (HSISR) task is correspondingly difficult in SR due to the unavailability of auxiliary high resolution images. To tackle this challenging task, different from the existing learning-based HSISR algorithms, in this paper we propose a novel framework, i.e., a 1D–2D attentional convolutional neural network, which employs a separation strategy to extract the spatial–spectral information and then fuse them gradually. More specifically, our network consists of two streams: a spatial one and a spectral one. The spectral one is mainly composed of the 1D convolution to encode a small change in the spectrum, while the 2D convolution, cooperating with the attention mechanism, is used in the spatial pathway to encode spatial information. Furthermore, a novel hierarchical side connection strategy is proposed for effectively fusing spectral and spatial information. Compared with the typical 3D convolutional neural network (CNN), the 1D–2D CNN is easier to train with less parameters. More importantly, our proposed framework can not only present a perfect solution for the HSISR problem, but also explore the potential in hyperspectral pansharpening. The experiments over widely used benchmarks on SISR and hyperspectral pansharpening demonstrate that the proposed method could outperform other state-of-the-art methods, both in visual quality and quantity measurements.
Distributed Fiberoptic Sensor for Simultaneous Humidity and Temperature Monitoring Based on Polyimide-Coated Optical Fibers
Authors: Stajanca Pavol , Hicke Konstantin , Krebber Katerina
Published: December 2019

Along temperature, humidity is one of the principal environmental factors that plays an important role in various application areas. Presented work investigates possibility of distributed fiberoptic humidity monitoring based on humidity-induced strain measurement in polyimide (PI)-coated optical fibers. Characterization of relative humidity (RH) and temperature response of four different commercial PI- and one acrylate-coated fiber was performed using optical backscattering reflectometry (OBR). The study addresses issues of temperature-humidity cross-sensitivity, fiber response stability, repeatability, and the influence of annealing. Acrylate-coated fiber exhibited rather unfavorable nonlinear RH response with strong temperature dependence, which makes it unsuitable for humidity sensing applications. On the other hand, humidity response of PI-coated fibers showed good linearity with fiber sensitivity slightly decreasing at rising temperatures. In the tested range, temperature sensitivity of the fibers remained humidity independent. Thermal annealing was shown to considerably improve and stabilize fiber RH response. Based on performed analysis, a 20 m sensor using the optimal PI-coated fibers was proposed and constructed. The sensor uses dual sensing fiber configuration for mutual decoupling and simultaneous measurement of temperature and RH variations. Using OBR, distributed dual temperature-RH monitoring with cm spatial resolution was demonstrated for the first time.
Continuous Authentication of Automotive Vehicles Using Inertial Measurement Units
Authors: Baldini Gianmarco , Geib Filip , Giuliani Raimondo
Published: December 2019

The concept of Continuous Authentication is to authenticate an entity on the basis of a digital output generated in a continuous way by the entity itself. This concept has recently been applied in the literature for the continuous authentication of persons on the basis of intrinsic features extracted from the analysis of the digital output generated by wearable sensors worn by the subjects during their daily routine. This paper investigates the application of this concept to the continuous authentication of automotive vehicles, which is a novel concept in the literature and which could be used where conventional solutions based on cryptographic means could not be used. In this case, the Continuous Authentication concept is implemented using the digital output from Inertial Measurement Units (IMUs) mounted on the vehicle, while it is driving on a specific road path. Different analytical approaches based on the extraction of statistical features from the time domain representation or the use of frequency domain coefficients are compared and the results are presented for various conditions and road segments. The results show that it is possible to authenticate vehicles from the Inertial Measurement Unit (IMU) recordings with great accuracy for different road segments.
VaryBlock: A Novel Approach for Object Detection in Remote Sensed Images
Authors: Zhang Heng , Wu Jiayu , Liu Yanli , Yu Jia
Published: December 2019

In recent years, the research on optical remote sensing images has received greater and greater attention. Object detection, as one of the most challenging tasks in the area of remote sensing, has been remarkably promoted by convolutional neural network (CNN)-based methods like You Only Look Once (YOLO) and Faster R-CNN. However, due to the complexity of backgrounds and the distinctive object distribution, directly applying these general object detection methods to the remote sensing object detection usually renders poor performance. To tackle this problem, a highly efficient and robust framework based on YOLO is proposed. We devise and integrate VaryBlock to the architecture which effectively offsets some of the information loss caused by downsampling. In addition, some techniques are utilized to facilitate the performance and to avoid overfitting. Experimental results show that our proposed method can enormously improve the mean average precision by a large margin on the NWPU VHR-10 dataset.
An Automatic Head Surface Temperature Extraction Method for Top-View Thermal Image with Individual Broiler
Authors: Xiong Xingguo , Lu Mingzhou , Yang Weizhong , Duan Guanghui , Yuan Qingyan , Shen Mingxia , Norton Tomas , Berckmans Daniel
Published: December 2019

Surface temperature variation in a broiler’s head can be used as an indicator of its health status. Surface temperatures in the existing thermograph based animal health assessment studies were mostly obtained manually. 2185 thermal images, each of which had an individual broiler, were captured from 20 broilers. Where 15 broilers served as the experimental group, they were injected with 0.1mL of pasteurella inoculum. The rest, 5 broilers, served as the control group. An algorithm was developed to extract head surface temperature automatically from the top-view broiler thermal image. Adaptive K-means clustering and ellipse fitting were applied to locate the broiler’s head region. The maximum temperature inside the head region was extracted as the head surface temperature. The developed algorithm was tested in Matlab® (R2016a) and the testing results indicated that the head region in 92.77% of the broiler thermal images could be located correctly. The maximum error of the extracted head surface temperatures was not greater than 0.1 °C. Different trend features were observed in the smoothed head surface temperature time series of the broilers in experimental and control groups. Head surface temperature extracted by the presented algorithm lays a foundation for the development of an automatic system for febrile broiler identification.
A Clamping Force Estimation Method Based on a Joint Torque Disturbance Observer Using PSO-BPNN for Cable-Driven Surgical Robot End-Effectors
Authors: Wang Zhengyu , Wang Daoming , Chen Bing , Yu Lingtao , Qian Jun , Zi Bin
Published: December 2019

The ability to sense external force is an important technique for force feedback, haptics and safe interaction control in minimally-invasive surgical robots (MISRs). Moreover, this ability plays a significant role in the restricting refined surgical operations. The wrist joints of surgical robot end-effectors are usually actuated by several long-distance wire cables. Its two forceps are each actuated by two cables. The scope of force sensing includes multidimensional external force and one-dimensional clamping force. This paper focuses on one-dimensional clamping force sensing method that do not require any internal force sensor integrated in the end-effector’s forceps. A new clamping force estimation method is proposed based on a joint torque disturbance observer (JTDO) for a cable-driven surgical robot end-effector. The JTDO essentially considers the variations in cable tension between the actual cable tension and the estimated cable tension using a Particle Swarm Optimization Back Propagation Neural Network (PSO-BPNN) under free motion. Furthermore, a clamping force estimator is proposed based on the forceps’ JTDO and their mechanical relations. According to comparative analyses in experimental studies, the detection resolutions of collision force and clamping force were 0.11 N. The experimental results verify the feasibility and effectiveness of the proposed clamping force sensing method.
Perception Sensors for Road Applications
Authors: Jiménez Felipe
Published: December 2019

New assistance systems and the applications of autonomous driving of road vehicles imply ever-greater requirements for perception systems that are necessary in order to increase the robustness of decisions and to avoid false positives or false negatives [...]
Development of Human Serum Albumin Selective Fluorescent Probe Using Thieno[3,2-b]pyridine-5(4H)-one Fluorophore Derivatives
Authors: Lee Suji , Sung Dan-Bi , Kang Seungyoon , Parameswaran Saravanan , Choi Jun-Ho , Lee Jong Seok , Han Min Su
Published: December 2019

The level of human serum albumin (HSA) in biological fluids is a key health indicator and its quantitative determination has great clinical importance. In this study, we developed a selective and sensitive fluorescent HSA probe by fluorescence-based high-throughput screening of a set of fluorescent thieno[3,2-b]pyridine-5(4H)-one derivatives against major plasma proteins: HSA, bovine serum albumin (BSA), globulin, fibrinogen, and transferrin. The fluorophore chosen finally (4) showed noticeable fluorescence enhancement in the presence of HSA (160-fold increase), and it exhibited rapid response, high sensitivity (detection limit 8 nM), and the ability to clearly distinguish HSA from BSA in pH 9 buffer condition. Moreover, the probe could be applicable to detect trace amounts of HSA in an artificial urine sample; further, it might be applied to the determination of the HSA concentration in complex biological samples for pre-clinical diagnosis.
3D Tensor Based Nonlocal Low Rank Approximation in Dynamic PET Reconstruction
Authors: Xie Nuobei , Chen Yunmei , Liu Huafeng
Published: December 2019

Reconstructing images from multi-view projections is a crucial task both in the computer vision community and in the medical imaging community, and dynamic positron emission tomography (PET) is no exception. Unfortunately, image quality is inevitably degraded by the limitations of photon emissions and the trade-off between temporal and spatial resolution. In this paper, we develop a novel tensor based nonlocal low-rank framework for dynamic PET reconstruction. Spatial structures are effectively enhanced not only by nonlocal and sparse features, but momentarily by tensor-formed low-rank approximations in the temporal realm. Moreover, the total variation is well regularized as a complementation for denoising. These regularizations are efficiently combined into a Poisson PET model and jointly solved by distributed optimization. The experiments demonstrated in this paper validate the excellent performance of the proposed method in dynamic PET.
An Ensemble Convolutional Neural Networks for Bearing Fault Diagnosis Using Multi-Sensor Data
Authors: Liu Yang , Yan Xunshi , Zhang Chen-an , Liu Wen
Published: December 2019

Multi-sensor data fusion is a feasible technique to achieve accurate and robust results in fault diagnosis of rotating machinery under complex conditions. However, the problem of information losses is always ignored during the fusion process. To solve above problem, an ensemble convolutional neural network model is proposed for bearing fault diagnosis. The framework of the proposed model contains three convolutional neural network branches: one multi-channel fusion convolutional neural network branch and two 1-D convolutional neural network branches. The former branch extracts the coupling features based on multi-sensor data and the latter two branches extract the inherent features based on single-sensor data, which can collect comprehensive fault information and reduce information losses. Furthermore, the support vector machine ensemble strategy is employed to fuse the results of multiple branches, which can improve the generalization and robustness of the proposed model. The experiments show that the proposed can obtain more effective and robust results than other methods.
The Growth of Ga2O3 Nanowires on Silicon for Ultraviolet Photodetector
Authors: Alhalaili Badriyah , Vidu Ruxandra , Islam M. Saif
Published: December 2019

We investigated the effect of silver catalysts to enhance the growth of Ga2O3 nanowires. The growth of Ga2O3 nanowires on a P+-Si (100) substrate was demonstrated by using a thermal oxidation technique at high temperatures (~1000 °C) in the presence of a thin silver film that serves as a catalyst layer. We present the results of morphological, compositional, and electrical characterization of the Ga2O3 nanowires, including the measurements on photoconductance and transient time. Our results show that highly oriented, dense and long Ga2O3 nanowires can be grown directly on the surface of silicon. The Ga2O3 nanowires, with their inherent n-type characteristics formed a pn heterojunction when grown on silicon. The heterojunction showed rectifying characteristics and excellent UV photoresponse.
Success Factors of Irrigation Projects Based on A "Public–Private Partnership" Model in A Mountainous Area: A Case Study in the Nujiang River Valley, China
Authors: Li Yanbo , Hu Jinming , Di Weijiao , Zhang Liyun , Suman Daniel Oscar , Zhu Hong
Published: December 2019

Irrigation systems are critical for food security and drought adaptation in mountainous areas. However, lack of funding and low efficacy of government-funded irrigation projects hinders irrigation infrastructure development. A public–private partnership (PPP) model is recommended for irrigation development, but its application in mountainous areas has not been well-documented and analyzed. Based on a case study of pumping station projects in the Lujiang Flatland in the Nujiang River Valley of Southwestern China, this paper aims to reveal the critical success factors of the PPP model in the development of agricultural irrigation infrastructure in mountainous areas. Results showed that the basic models of PPP projects in the study area can be described as follows: (1) private companies invested in and constructed pumping stations; (2) communities operated the stations; (3) farmers paid for the services; and (4) private companies profited from charging water fees, obtaining policy supports, or utilizing farmlands. The main success factors include: (1) rational project design according to local conditions; (2) multi-centered management mechanisms; (3) balanced cost- and risk-sharing mechanisms; and (4) building mutual trusts among stakeholders. This study offers applicable lessons and useful insights for irrigation water development projects and adaptation to drought in mountainous rural communities.