bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cloud cover and cloud types in the Eurasian Arctic in 1936–2012
Authors: Chernokulsky Alexander , Esau Igor 
Published: June 2019

AbstractThe Arctic is a cloudy place. It has been recognized that the Arctic cloud cover is sensitive to different climatic factors such as sea ice extent and atmospheric circulation indices. Moreover, several influential climate feedbacks, for example, the summertime cloud‐radiation feedback, have been recognized. Yet, the cloud cover studies were limited in time to the satellite era observations and fragmentary data sets from meteorological stations. Here, we present the complete long‐term cloud records from 86 meteorological stations in the Eurasian Arctic. The stations are located on the coast and islands of the region from the Barents to Chukchi Seas. Thus, this study is complementing and extending the study by Chernokulsky et al. (2017) where the cloud data from the Norwegian through Kara Seas were presented. Our data set comprises the entire period of observations at each station. However, we present the area‐wide analysis only over the historical period of 1936–2012 when there were sufficient density of stations and cloud records for the coherent analysis. The total cloud cover, which on multiannual average constitutes 69–74% in different areas, increases in the warmer periods. The strongest increase is found in the convective cloud cover, particularly in the Chukchi Sea. We observe statistical evidence of transition between stratiform and convective cloud types. The cloud characteristics reveal the strongest correlations with the Atlantic circulation indices and the sea ice concentration in all Eurasian Arctic areas. The correlations with the Pacific circulation indices are much less significant. The obtained cloud data sets disclose much smaller scale features and variability, which deserve further research.
Dendritic Polyglycerol‐Derived Nano‐Architectures as Delivery Platforms of Gemcitabine for Pancreatic Cancer
Authors: Ray Priyanka , Ferraro Magda , Haag Rainer , Quadir Mohiuddin 
Published: June 2019

AbstractDendritic polyglycerol‐co‐polycaprolactone (PG‐co‐PCL)‐derived block copolymers are synthesized and explored as nanoscale drug delivery platforms for a chemotherapeutic agent, gemcitabine (GEM), which is the cornerstone of therapy for pancreatic ductal adenocarcinoma (PDAC). Current treatment strategies with GEM result in suboptimal therapeutic outcome owing to microenvironmental resistance and rapid metabolic degradation of GEM. To address these challenges, physicochemical and cell‐biological properties of both covalently conjugated and non‐covalently stabilized variants of GEM‐containing PG‐co‐PCL architectures have been evaluated. Self‐assembly behavior, drug loading and release capacity, cytotoxicity, and cellular uptake properties of these constructs in monolayer and in spheroid cultures of PDAC cells are investigated. To realize the covalently conjugated carrier systems, GEM, in conjunction with a tertiary amine, is attached to the polycarbonate block grafted from the PG‐co‐PCL core. It is observed that pH‐dependent ionization properties of these amine side‐chains direct the formation of self‐assembly of block copolymers in the form of nanoparticles. For non‐covalent encapsulation, a facile “solvent‐shifting” technique is adopted. Fabrication techniques are found to control colloidal and cellular properties of GEM‐loaded nanoconstructs. The feasibility and potential of these newly developed architectures for designing carrier systems for GEM to achieve augmented prognosis for pancreatic cancer are reported.
Insight into picophytoplankton diversity of the subarctic White Sea—The first recording of Pedinophyceae in environmental DNA
Authors: Milyutina Irina A. , Belevich Tatyana A. , Ilyash Lyudmila V. , Troitsky Aleksey V. 
Published: June 2019

AbstractOperational taxonomic units 94%–95% similar to the known Pedinophyceae were found as a result of high‐through sequencing of 18S rDNA V4 amplicons of environmental DNA from the summer picophytoplankton samples from the White Sea. Partial sequence of a ribosomal operon (the 5,298 bp includes partial 18S and 28S rDNA, complete 5.8S rDNA, ITS1, and ITS2 sequences) and a partial 2,112 bp chloroplast 23S rDNA sequence White Sea Pedinophyceae was amplified from metagenomic DNA by specific primers and sequenced. A new phylotype was designated as uncultured Pedinophyceae WS. On Chlorophyta phylogenetic trees the discovered phylotype occupies a basal position in the Marsupiomonadales clade. The synapomorphic base substitutions in rRNA hairpins confirm the relationship of Pedinophyceae WS to Marsupiomonadales and its difference from known genera of the order. The obtained results extend knowledge of picophytoplankton diversity in subarctic waters.
Improvement of the gain and the axial ratio of a circular polarization microstrip antenna by using a metamaterial superstrate
Authors: Safari Dehnavi Mahboubeh , Razavi Seyyed Mohammad Javad , Mohseni Armaki Seyyed Hossien 
Published: June 2019

AbstractIn this article, a new design of circular polarized (CP) microstrip antenna for 2.2 GHz band applications is introduced. This compact design has achieved return loss and axial ratio lower than −10 and 3 dB, respectively. Next, a polarized insensitive metamaterial surface acting as a superstrate is proposed for improvement of the antenna characteristics. By putting the suggested double stacked meta‐surface layer over a CP microstrip antenna, the radiation pattern of antenna has been improved significantly. As a result, the antenna gain is enhanced about 4.7 dBi and simultaneously the overlap of return loss band and axial ratio band is increased about 3%. The structure is simulated in CST MICROWAVE STUDIO software and the results show reasonable conformity with the measurements.
Computational and experimental investigation of RF‐induced heating for multiple orthopedic implants
Authors: Guo Ran , Zheng Jianfeng , Wang Yu , Zeng Qi , Wang Qingyan , Yang Rui , Kainz Wolfgang , Chen Ji 
Published: June 2019

PurposeThis paper investigates the RF‐induced heating for multiple adjacent orthopedic implants under MRI at 1.5T and 3T exposure. When multiple implants are closely spaced to each other, the interactions between the implants may affect the RF‐induced heating. Traditional RF‐induced heating labeling is often only applicable to configurations of an individual implant, and is not applicable for multi‐implant configurations. Therefore, the aim of this study is to evaluate the effects of multiple orthopedic implants on RF‐induced heating and to propose potential appropriate instructions for safe scanning of multi‐implantable orthopedic implants.MethodsTypical plate and nail implants were used as examples. The effects of implant configuration, relative positions, and number of implants were investigated. Numerical simulations were conducted using full‐wave electromagnetic simulation software. Experimental measurements at 1.5 T were performed to validate the numerical results.ResultsNumerical results indicate that, due to device interaction, the RF‐induced heating of multiple medical implants can be significantly different from that of a single implant. The measured temperature rise for multiple devices could be 2.7 times larger than that of a single implant.ConclusionOur results confirm that RF‐induced heating of multiple implants can be quite different, and do not follow simple superposition of the results from single devices. Instructions for safe scanning of individual orthopedic devices would not be applicable to multi‐implant configurations.
Rapid framework for quantitative magnetization transfer imaging with interslice magnetization transfer and dictionary‐driven fitting approaches
Authors: Kim Jae‐Woong , Lee Sul‐Li , Choi Seung Hong , Park Sung‐Hong 
Published: June 2019

PurposeTo develop a rapid framework for quantitative magnetization transfer (qMT) imaging based on the 2D interslice MT and dictionary‐driven fitting approaches.MethodsSequential balanced steady‐state free precession (bSSFP) scanning was performed on a whole human brain in a total of 12 conditions from six different interslice gaps and two different flip angles. To obtain qMT maps, the acquired 12 datasets were fitted to a dictionary predefined by using Bloch equation simulations based on the two‐pool MT model. The proposed qMT method was compared to the conventional qMT methods, in terms of qMT parameter maps and processing time.ResultsThe proposed method yielded qMT maps similar to those of the conventional method, indicating feasibility of modulating MT saturation frequency and power with the interslice gap and flip angle. The whole‐brain qMT imaging could be completed in 8 min because of the absence of separate MT pulses. The time for processing qMT parameters was significantly reduced through the dictionary‐driven approach; it is 1000 times shorter than that without the dictionary‐driven approach and 3 times shorter than that with the spoiled gradient recalled echo‐qMT method that uses an analytical solution.ConclusionThe proposed dictionary–driven interslice qMT imaging provides qMT maps close to those from the conventional method with significantly reduced scan time and postprocessing time, which can make qMT imaging more clinically acceptable.
Free intramuscular Mg2+ concentration calculated using both 31P and 1H NMRS‐based pH in the skeletal muscle of Duchenne muscular dystrophy patients
Authors: Reyngoudt Harmen , Lopez Kolkovsky Alfredo L. , Carlier Pierre G. 
Published: June 2019

Early studies have demonstrated that (total) magnesium was decreased in skeletal muscle of Duchenne muscular dystrophy (DMD) patients. Free intramuscular Mg2+ can be derived from 31P NMRS measurements. The value of free intramuscular magnesium concentration ([Mg2+]) is highly dependent on precise knowledge of intracellular pH, which is abnormally alkaline in dystrophic muscle, possibly due to an expanded interstitial space, potentially causing an underestimation of [Mg2+]. We have recently shown that intracellular pH can be derived using 1H NMRS of carnosine.Our aim was to determine whether 31P NMRS‐based [Mg2+] is, in fact, abnormally low in DMD patients, taking advantage of the 1H NMRS‐based pH. A comparative analysis was, therefore, made between [Mg2+] values calculated with both 1H and 31P NMRS‐based approaches to determine pH in 25 DMD patients, on a 3‐T clinical NMR scanner. [Mg2+] was also assessed with 31P NMRS only in (forearm or leg) skeletal muscle of 60 DMD patients and 63 age‐matched controls. Additionally, phosphodiester levels as well as quantitative NMRI indices including water T2, fat fraction, contractile cross‐sectional area and one‐year changes were evaluated.The main finding was that the significant difference in [Mg2+] between DMD patients and controls was preserved even when the intracellular pH determined with 1H NMRS was similar in both groups. Consequently, we observed that [Mg2+] is significantly lower in DMD patients compared with controls in the larger database where only 31P NMRS data were obtained. Significant yet weak correlations existed between [Mg2+] and PDE, water T2 and fat fraction.We concluded that low [Mg2+] is an actual finding in DMD, whether intracellular pH is normal or alkaline, and that it is a likely consequence of membrane leakiness. The response of Mg2+ to therapeutic treatment remains to be investigated in neuromuscular disorders.Free [Mg2+] determination with 31P NMRS is highly dependent on a precise knowledge of intracellular pH. The pH of Duchenne muscular dystrophy (DMD) patients, as determined by 31P NMRS, is abnormally alkaline. We have recently shown that intracellular pH could be determined using 1H NMRS of carnosine, and that intracellular pH was alkaline in a proportion of, but not all, DMD patients with a 31P NMRS‐based alkaline pH. Taking advantage of this 1H NMRS‐based intracellular pH, we found that free intramuscular [Mg2+] is in fact abnormally low in DMD patients.
Heterogeneously Catalysed Oxidative Dehydrogenation of Menthol in a Fixed‐Bed Reactor in the Gas Phase
Authors: Kulik Anna , Neubauer Katja , Eckelt Reinhard , Bartling Stephan , Panten Johannes , Köckritz Angela 
Published: June 2019

AbstractFor the first time, the oxidative dehydrogenation of (−)‐menthol to (−)‐menthone and (+)‐isomenthone in a marketable quality was carried out in a continuous gas phase reactor as a sustainable process using molecular oxygen as green oxidant and solid catalysts which do not contaminate the product mixture and which are easily to remove. The diastereomeric purity remained largely unchanged. Three types of catalysts were found to be very active and selective in the formation of menthone and isomenthone: AgSr/SiO2, CuO distributed on a basic support and RuMnCe/CeO2, where Ru, Mn and Ce exist in an oxidized state. The best overall yield of menthon/isomenthone obtained with an Ag‐based catalyst was 58 % at 64 % selectivity, with a Cu‐based catalyst 41 % at 51 % selectivity and with a Ru‐based catalyst 68 % at 73 % selectivity. Reaction conditions were widely optimized.
Low‐frequency dielectric performance of polyimide composites containing amorphous polymer‐derived SiCN ceramics
Authors: Sun Dandan , Gao Yan , Liu Jinling , Ma Baisheng , Wang Yiguang 
Published: June 2019

AbstractHigh‐dielectric‐constant polymer‐matrix composites have potential applications as embedded capacitors. In this paper, an amorphous polymer‐derived SiCN ceramic was incorporated into a polyimide (PI) matrix by in situ polymerization for the first time. The resulting SiCN/PI composite showed good thermal stability below 500°C, with the SiCN filler being homogeneously dispersed in the PI matrix. The dielectric properties of the SiCN/PI composites were investigated over a broad frequency range (0.1‐106 Hz). The dielectric properties of the SiCN/PI composites at low frequencies revealed a weak percolation phenomenon similar to that shown by conductive/polymer composites and the calculated percolation threshold was 22.8 vol%. At SiCN loadings of 25 vol%, the SiCN/PI composites showed a high dielectric constant of 190 at 0.1 Hz, which is 57 times higher than that of pure PI (3.3). The conductivity of the 25 vol% SiCN/PI composite was as low as 8.5 × 10−10 S·cm−1. These results could be explained by the unique microstructure of the polymer‐derived SiCN ceramic, containing an amorphous Si matrix and a free carbon phase. This study revealed SiCN/PI composites as promising dielectric materials with promising applications in energy storage fields.
Conjugated random terpolymers based on benzodithiophene, diketopyrrolopyrrole, and 8,10‐bis(thiophen‐2‐yl)‐2,5‐di(nonadecan‐3‐yl)bis[1,3]thiazolo[4,5‐f:5′,4′‐h]thieno[3,4‐b]quinoxaline for Efficient Polymer Solar Cell
Authors: Keshtov Mukhamed L. , Kuklin Sergei A. , Konstantinov Igor O. , Ostapov Ilya E. , Godovsky Dmitrii Y. , Makhaeva Elena E. , Xie Zhiyuan , Sharma Ganesh D. 
Published: June 2019

ABSTRACTA series of novel donor–acceptor (D–A) random conjugated terpolymers P2‐P4 along with the homopolymers P1 (BDT‐DPP) and P5 (BDT‐BTDQ) were designed and synthesized by copolymerizing a benzo[1,2‐b:4,5‐b]dithiophene (BDT) donor with an electron‐deficient diketopyrrolo[3,4‐c]pyrrole (DPP) unit and a benzothiadiazolo[3,4‐e]quinoxaline (BTDQ) moieties of different electron‐withdrawing strengths, and the resultant terpolymers showed broad absorption profile ranging from 300 to 1200 nm. The HOMO levels of the polymers were adjusted from −5.23 to −5.11 eV, and the optical bandgaps were controlled from 1.32 to 1.13 eV by changing the molar ratio of DPP and BTDQ acceptors. These terpolymers were used as a donor along with PC71BM as an acceptor for the creation of polymer solar cells, and the performance was optimized via variable the donor to acceptor ratio and solvent vapor annealing. The polymer solar cells made from the random terpolymer P3 showed the highest overall power conversion efficiency of (9.27%), which is higher than that for the corresponding homo‐polymers counterparts, that is, P1 (7.27%) and P5 (7.68%). The results demonstrate that the designing of random D‐A1‐D‐A2 terpolymers may be the best approach for efficient polymer solar cells. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 1478–1485
Shelf life extension of refrigerated breaded hake medallions packed into active edible fish gelatin films
Authors: Neira Laura M. , Agustinelli Silvina P. , Ruseckaite Roxana A. , Martucci Josefa F. 
Published: June 2019

Fish consumption has increased in recent years. However, fish meat is highly perishable, which demonstrates the need for technologies to preserve its quality. Edible films might provide an alternative to extend the shelf life of fish. The goal of this study was to evaluate the efficiency of edible fish gelatin films added with carvacrol (blended: FG‐0.6CRV and grafted: FG/CRV‐g‐FG) on the quality retention of commercially available prefried breaded hake medallions (BHMs). Samples of BHM were wrapped into films, heat sealed, and stored at −4 ± 1 °C for 49 days. Free carvacrol gelatin films and the unwrapped medallions were used as controls. After predetermined periods of time, samples were analysed in terms of microbiological and physicochemical properties. Overall the storage period, the total volatile basic nitrogen value (TVBN) and the total psychrotrophic bacteria counts (TPC) were significantly lesser in BHM wrapped in FG‐0.6CRV than in the other samples. The total oxidation index (TOI), peroxide value (PV), and p‐anisidine value (AV) were reduced by 18%, 30%, and 16%, respectively, compared with controls. FG/CRV‐g‐FG film was not efficient to reduce the microbial spoilage or the oxidation, probably due to the retention of CRV into the matrix avoiding its migration towards the foodstuff, proving the importance of checking the films functionality in real food systems. Sensory evaluation of fried samples wrapped in FG‐0.6CRV was also performed. The results indicate that the medallions can be directly cooked and consumed without removing the packaging with a good acceptance by the consumer.
Bit rate conditions to stabilize an uncertain scalar continuous‐time linear system with clock offset
Authors: Ling Qiang , Chen Rui , Dou Rundong 
Published: June 2019

SummaryThis paper aims to stabilize a scalar continuous‐time linear system that transmits its feedback information through a digital communication network. The finite bit rate of the feedback network plays a critical role in the input‐to‐state stability of that system. Stabilizing bit rate conditions depend on not only the system matrix but also the uncertainty of the system matrix and the unknown clock offset between the transmitter (sensor) and the receiver (controller). Compared with the current literature, this paper can handle the system matrix uncertainty and clock offset through implementing an event‐triggered sampling strategy and derive stabilizing conditions that require lower bit rates than those of periodic sampling strategies. Such bit rate saving mainly comes from the fact that our event‐triggered strategy can extract state information from the receive time instants of feedback packets without any extra communication cost. Simulations are done to confirm the effectiveness of the obtained stabilizing bit rate conditions.
Advances in the Experimental and Theoretical Understandings of Antibiotic Conjugated Gold Nanoparticles for Antibacterial Applications
Authors: Khandelwal Puneet , Singh Dheeraj K. , Poddar Pankaj 
Published: June 2019

AbstractThe worldwide bacterial resistance to a wide range of antibiotics originates a global health concern and calls for the development of new antibacterial agents. Over the recent years, nanomaterials‐based agents have been proven to be useful for the effective antibacterial applications. Notably, the gold nanoparticles (AuNPs) draw particular attention due to their biological inertness and easy surface functionalization. It is now established that the antibiotic functionalization on the AuNPs surfaces increases the antibacterial efficacy even towards the antibiotic‐resistant bacterial cells. Moreover, the antibacterial efficacy can be further enhanced by photothermal therapy using antibiotic conjugated AuNPs. In this review article, we have reviewed the advances in the development of the synthesis methods of antibiotic conjugated AuNPs and gold nanoclusters, and their antibacterial efficacy. We have also discussed the developments in the theoretical understandings behind the interaction of antibiotic molecules with gold surface and its relation to the antibacterial activity. We believe that few parameters including the selection of antibiotic molecules, the method of its attachment to AuNPs, the purification of antibiotic conjugated AuNPs, and the quantification of conjugated antibiotic are crucial and needs to be properly addressed. Moreover, there are many other future directions discussed, for using antibiotic conjugated AuNPs more effectively for antibacterial therapy.
Effect of B, Al and Ga atoms on structures, electrical and optical properties of BeO nanotube
Authors: Sabzehzari Mozhgan , Ahmadi Tayebeh , Bahrami Hamed 
Published: June 2019

AbstractIn this research, the density functional theory (DFT) method was used to study the structural, electrical, linear and nonlinear optical (NLO) properties of pristine and B, Al and Ga doped BeO nanotube. Slight structural deformation, as the consequence of doping atom presence, was observed. The dipole moment of BeO nanotube was increased in the doping atom presence. In the B, Al and Ga atoms presence, a kind of reduction in Eg of nanotube was observed in which, in the B case, the decrease in Eg was more substantial. In this sense, it is worth noting that higher electrical conductivity is associated with lower Eg. The two CAM−B3LYP and ωB97XD methods were used to calculate the optical properties of pristine and doped BeO nanotubes. It was shown that the polarizability of nanotube was slightly increased in the doping atoms presence. Besides, the B<Al<Ga order was observed for the polarizability increasing. According to the findings of the research, the doping atoms extremely influenced the value of the first hyperpolarizability of BeO nanotube. The results would be useful in designing and constructing new NLO active materials.
Microwave‐Assisted Rapid Regioselective One‐Pot Synthesis of Novel 2‐Oxothiazolidine Dicarboxylate
Authors: Bangade Vikas Madhukar , Mali Prakash Rambhau , Shirsat Prashishkumar Kishan , Meshram Harshadas Mitaram 
Published: June 2019

AbstractA regioselective synthesis of 2‐oxothiazolidine dicarboxylate (OTDC) under microwave irradiations is reported. Methoxylation, demethylation and double reductive cyclization occurs in single step by three component one pot reaction under microwave irradiations. The microwave irradiations, planar arrangement of intermediate imino(sp2)‐thio‐maleate and in situ demethylation considered as driving forces for regioselective cyclization.