bluuebunny/crossref_metadata_2025_split huggingface dataset:
Photodissociation of CO in the outflow of evolved stars
Authors: Saberi M. , Vlemmings W. H. T. , De Beck E. 
Published: April 2019

Context. Ultraviolet (UV) photodissociation of carbon monoxide (CO) controls the abundances and distribution of CO and its photodissociation products. This significantly influences the gas-phase chemistry in the circumstellar material around evolved stars. A better understanding of CO photodissociation in outflows also provides a more precise estimate of mass-loss rates.
Aims. We aim to update the CO photodissociation rate in an expanding spherical envelope assuming that the interstellar radiation field (ISRF) photons penetrate through the envelope. This will allow us to precisely estimate the CO abundance distributions in circumstellar envelope around evolved stars.
Methods. We used the most recent CO spectroscopic data to precisely calculate the depth dependency of the photodissociation rate of each CO dissociating line. We calculated the CO self- and mutual-shielding functions in an expanding envelope. We investigated the dependence of the CO profile on the five fundamental parameters mass-loss rate, the expansion velocity, the CO initial abundance, the CO excitation temperature, and the strength of the ISRF.
Results. Our derived CO envelope size is smaller than the commonly used radius derived by Mamon et al. (1988, ApJ, 328, 797). The difference between results varies from 1 to 39% and depends on the H2 and CO densities of the envelope. We list two fitting parameters for a large grid of models to estimate the CO abundance distribution. We demonstrate that the CO envelope size can differ between outflows with the same effective content of CO, but different CO abundance, mass-loss rate, and the expansion velocity as a consequence of differing amounts of shielding by H2 and CO.
Conclusions. Our study is based on a large grid of models employing an updated treatment of the CO photodissociation, and in it we find that the abundance of CO close to the star and the outflow density both can have a significant effect on the size of the molecular envelope. We also demonstrate that modest variations in the ISRF can cause measurable differences in the envelope extent.
Is there more than meets the eye? Presence and role of sub-micron grains in debris discs
Authors: Thebault P. , Kral Q. 
Published: April 2019

Context. The presence of sub-micron grains has been inferred in several debris discs, usually because of a blue colour of the spectrum in scattered light or a pronounced silicate band around 10 μm, even though these particles should be blown out by stellar radiation pressure on very short timescales. So far, no fully satisfying explanation has been found for this apparent paradox.
Aims. We investigate the possibility that the observed abundances of sub-micron grains could be naturally produced in bright debris discs, where the high collisional activity produces them at a rate high enough to partially compensate for their rapid removal. We also investigate to what extent this potential presence of small grains can affect our understanding of some debris disc characteristics.
Methods. We used a numerical collisional code to follow the collisional evolution of a debris disc down to sub-micron grains far below the limiting blow-out size sblow. We considered compact astrosilicates and explored different configurations: A and G stars, cold and warm discs, bright and very bright systems. We then produced synthetic spectra and spectral energy distributions, where we identified and quantified the signature of unbound sub-micron grains.
Results. We find that in bright discs (fractional luminosity ≳10−3) around A stars, the number of sub-micron grains is always high enough to leave detectable signatures in scattered light where the disc colour becomes blue, and also in the mid-IR (10 ≲ λ ≲ 20 μm), where they boost the disc luminosity by at least a factor of 2 and induce a pronounced silicate solid-state band around 10 μm. We also show that with this additional contribution of sub-micron grains, the spectral energy distribution can mimic that of two debris belts separated by a factor of ~2 in radial distance. For G stars, the effect of s ≤ sblow grains remains limited in the spectra although they dominate the geometrical cross section of the system. We also find that for all considered cases, the halo of small (bound and unbound) grains that extends far beyond the main disc contributes to ~50% of the flux up to λ ~ 50 μm wavelengths.
Misplaced Ventricular Lead via an Atrial Septal Defect–Percutaneous Extraction
Authors: Easo Jerry , Book Malte , Hakmi Samer , Weymann Alexander 
Published: April 2019

Background Necessity for lead removal in this case was after 12 years due to mitral valve regurgitation caused by retraction of the posterior leaflet by the inadvertently misplaced lead.
Case Description This history describes a 45-year-old woman with history of multiple cardiac operations at young age with an abandoned defibrillator lead via a patent atrial septal defect. Lead extraction was performed with first described use of rotational dilating sheaths to reduce emboli risk, hoping to avoid a fourth surgical procedure with high risk.
Conclusions Percutaneous lead removal using rotational sheaths is possible even for misplaced leads after long-time intervals with acceptable operative risk.
Hybrid materials based on graphene derivatives and porphyrin metal-organic frameworks
Authors: Arslanov Vladimir V. , Kalinina Maria A. , Ermakova Elizaveta V. , Raitman Oleg A. , Gorbunova Yulia G. , Aksyutin Oleg E. , Ishkov Alexander G. , Grachev Vladimir A. , Tsivadze Aslan Yu. 
Published: April 2019

Domestic and foreign literature on methods for obtaining graphene and its derivatives [graphene oxide (GO) and reduced GO] as representatives of the family of 2D layered materials is analyzed. Particular attention is paid to GO. Great potential of post-synthetic modification as well as unique properties of the material and its derivatives make them promising for a variety of applications including biomedicine, ecology, optoelectronics, etc. Chemical and physical methods for the reduction of GO to obtain graphene-like materials similar in structure and properties to pure graphene obtained by direct mechanical cleavage are considered. Functionalization strategies of graphene materials are discussed. The preparation of hydro- and organogels as well as Pickering emulsions from graphene derivatives as precursors of porous monoliths are considered. The formation of aerogels based on graphene materials and methane adsorption on these porous structures are discussed. Basic information about hybrid materials containing graphene derivatives and metal-organic frameworks is given and their adsorption characteristics with respect to methane are evaluated. Covalent and noncovalent interactions in graphene – porphyrin hybrids are considered from the standpoint of formation of porphyrin architectures on the surface of graphene materials. Examples of the use of porphyrin – graphene composite materials in photo- and electrocatalysis, fuel cells and gas separation membranes are given.
The bibliography includes 243 references.
The impact of neglecting user-centered information design principles when delivering online information
Authors: Santos Lonsdale Maria dos , Lonsdale David J. , Lim Hye-Won 
Published: April 2019

Abstract
Information design principles are overlooked in cyber security awareness websites. An Information Design Process
Model has been devised to help frame and interpret how online information is processed and the role information design principles
play in facilitating that processing. Two websites have been compared, and results show significant differences in terms of
performance, behavior and perception. The results also show that in situations where serious information is at stake, such as
cyber security, a more accessible design does not seem to be sufficient to project a sense of trust and security among users. All
these findings have led to original insights regarding the design of online information in terms of lasting impression and
user-centered design approaches.
Vanillic acid in Panax ginseng root extract inhibits melanogenesis in B16F10 cells via inhibition of the NO/PKG signaling pathway
Authors: Liu Jianzeng , Xu Xiaohao , Jiang Rui , Sun Liwei , Zhao Daqing 
Published: April 2019

ABSTRACT
Panax ginseng C. A. Meyer has been widely used in skin care. Our previous study showed that the phenolic acids in ginseng root extract (GRE) impart inhibitory effects on melanogenesis. In this study, we found that as the most abundant component of phenolic acids in GRE, vanillic acid decreased tyrosinase activity and melanin levels with or without α-MSH stimulation and suppressed the expression of microphthalmia-associated transcription factor (MITF) and melanogenic enzymes in B16F10 cells. Furthermore, vanillic acid downregulated NOS activity, nitric oxide (NO) content, cGMP level, guanylate cyclase (GC) and protein kinase G (PKG) activity, and the phosphorylation of cAMP-response element-binding protein (CREB), whereas arbutin had no effect on the NO/PKG pathway. These findings indicate that vanillic acid in GRE suppressed melanogenesis by inhibiting the NO/PKG signaling pathways. This study provides a potential mechanism underlying the inhibitory effect of ginseng on melanogenesis.
Long non-coding RNA ZFAS1 regulates the malignant progression of gastric cancer via the microRNA-200b-3p/Wnt1 axis
Authors: Zhang Fan , Li Ying , Xu Weiran , He Liang , Tan Yan , Xu Hong 
Published: April 2019

ABSTRACT
Gastric cancer is a common malignant tumor. Studies from our laboratory or others have shown that long non-coding RNA (lncRNA) zinc finger antisense (ZFAS)1 often acts as an oncogene. However, the molecular underpinnings of how ZFAS1 regulates gastric cancer remain to be elucidated. Results showed that ZFAS1 expression was upregulated, and microRNA-200b-3p (miR-200b) expression was downregulated in gastric cancer tissues. MiR-200b overexpression suppressed the proliferation, cell cycle process, and Wnt/β-catenin signaling of gastric cancer cells. Subsequently, we identified miR-200b is a target of ZFAS1 and Wnt1 is a target of miR-200b. Furthermore, promotion of cancer malignant progression and activation of Wnt/β-catenin signaling induced by ZFAS1 was counteracted by increasing miR-200b expression. In vivo, ZFAS1 knockdown suppressed the tumorigenesis with the upregulated miR-200b and the inactive Wnt/β-catenin signaling. Summarily, we demonstrated a critical role of miR-200b in gastric cancer, and ZFAS1 can promote malignant progression through regulating miR-200b mediated Wnt/β-catenin signaling.
Uptake of adenine by purine permeases of Coffea canephora
Authors: Kakegawa Hirofumi , Shitan Nobukazu , Kusano Hiroaki , Ogita Shinjiro , Yazaki Kazufumi , Sugiyama Akifumi 
Published: April 2019

ABSTRACT
Purine permeases (PUPs) mediate the proton-coupled uptake of nucleotide bases and their derivatives into cytosol. PUPs facilitate uptake of adenine, cytokinins and nicotine. Caffeine, a purine alkaloid derived from xanthosine, occurs in only a few eudicot species, including coffee, cacao, and tea. Although caffeine is not an endogenous metabolite in Arabidopsis and rice, AtPUP1 and OsPUP7 were suggested to transport caffeine. In this study, we identified 15 PUPs in the genome of Coffea canephora. Direct uptake measurements in yeast demonstrated that CcPUP1 and CcPUP5 facilitate adenine – but not caffeine – transport. Adenine uptake was pH-dependent, with increased activity at pH 3 and 4, and inhibited by nigericin, a potassium–proton ionophore, suggesting that CcPUP1 and CcPUP5 function as proton-symporters. Furthermore, adenine uptake was not competitively inhibited by an excess amount of caffeine, which implies that PUPs of C. canephora have evolved to become caffeine-insensitive to promote efficient uptake of adenine into cytosol.
Anti-photoaging effect of skin cream manufactured with ziyuglycoside I isolated from Sanguisorba officinalis on ultraviolet B-induced hairless mice
Authors: Yun Mi-Young , Bae Eun-Young , Lee Seung-Woong , Yim Soon-Ho , Ly Sun-Yung , Choi Hwa-Jung 
Published: April 2019

ABSTRACT
In this study, skin cream containing ziyuglycoside I isolated from Sanguisorba officinalis was manufactured and examined the protective effects of the skin cream against UVB-induced hairless mice. UVB-induced hairless mice were topically treated with the skin cream once a day for 5 weeks. Application of the skin cream did not exhibit side effect on body growth showing normal body weight and food efficiency in the mice. The skin cream treatment also was inhibited mRNA expression of interleukin (IL)-1β, matrix metalloproteinase (MMP)-2, MMP-9, and MMP-2 protein expression in the mice. Furthermore, the skin cream treatment inhibits epidermal wrinkle formation, wrinkle depth, wrinkle thickness, and collagen degradation in UVB-induced hairless mice. Therefore, the skin cream was able to play a role in the attenuation of photoaging caused by UVB irradiation via downregulation of mRNA expression of inflammatory cytokine IL-1β, MMP-2, MMP-9, and suppression of MMP-2 proteins expression.
Fat Extract Improves Random Pattern Skin Flap Survival in a Rat Model
Authors: Cai Yizuo , Yu Ziyou , Yu Qian , Zheng Hongjie , Xu Yuda , Deng Mingwu , Wang Xiangsheng , Zhang Lu , Zhang Wenjie , Li Wei 
Published: April 2019

Abstract

Background
Adipose tissue and its derivatives, including adipose-derived stem cells, stromal vascular fraction (SVF), and SVF-gel, have been utilized in the treatment of many ischemic disorders. However, the utilization of these products is limited in clinical applications by concerns related to the presence of cells in these derivatives.

Objectives
This study aimed to isolate a cell-free fat extract (FE) from fat tissue and to evaluate its proangiogenic ability in vitro as well as its protective effects on skin flap survival in vivo.

Methods
FE was isolated from human fat via a mechanical approach. The concentrations of several growth factors in the FE were determined by enzyme-linked immunosorbent assay. The proangiogenic ability of FE was evaluated utilizing assays of the proliferation, migration, and tube formation in human umbilical vein endothelial cells in vitro. The protective effects of FE on the survival of random pattern skin flaps were investigated by subcutaneous injection into rats.

Results
Enzyme-linked immunosorbent assay results revealed that FE contained proangiogenic growth factors that promoted proliferation, migration, and tube formation in human umbilical vein endothelial cells in vitro. In addition, FE reduced skin flap necrosis and increased survival, as demonstrated by macroscopic measurements and blood flow analysis. Histological analysis revealed that FE treatment increased the capillary density.

Conclusions
FE is a cell-free, easy-to-prepare, and growth-factor–enriched liquid derived from human adipose tissue that possesses proangiogenic activity and improves skin flap survival by accelerating blood vessel formation. FE may be potentially used for treating ischemic disorders.
Systematic analysis of supervised machine learning as an effective approach to predicate β-lactam resistance phenotype in Streptococcus pneumoniae
Authors: Zhang Chaodong , Ju Yingjiao , Tang Na , Li Yun , Zhang Gang , Song Yuqin , Fang Hailing , Yang Liang , Feng Jie 
Published: April 2019

Abstract
Streptococcus pneumoniae is the most common human respiratory pathogen, and β-lactam antibiotics have been employed to treat infections caused by S. pneumoniae for decades. β-lactam resistance is steadily increasing in pneumococci and is mainly associated with the alteration in penicillin-binding proteins (PBPs) that reduce binding affinity of antibiotics to PBPs. However, the high variability of PBPs in clinical isolates and their mosaic gene structure hamper the predication of resistance level according to the PBP gene sequences. In this study, we developed a systematic strategy for applying supervised machine learning to predict S. pneumoniae antimicrobial susceptibility to β-lactam antibiotics. We combined published PBP sequences with minimum inhibitory concentration (MIC) values as labelled data and the sequences from NCBI database without MIC values as unlabelled data to develop an approach, using only a fragment from pbp2x (750 bp) and a fragment from pbp2b (750 bp) to predicate the cefuroxime and amoxicillin resistance. We further validated the performance of the supervised learning model by constructing mutants containing the randomly selected pbps and testing more clinical strains isolated from Chinese hospital. In addition, we established the association between resistance phenotypes and serotypes and sequence type of S. pneumoniae using our approach, which facilitate the understanding of the worldwide epidemiology of S. pneumonia.
kmcEx: memory-frugal and retrieval-efficient encoding of counted k-mers
Authors: Jiang Peng , Luo Jie , Wang Yiqi , Deng Pingji , Schmidt Bertil , Tang Xiangjun , Chen Ningjiang , Wong Limsoon , Zhao Liang 
Published: April 2019

Abstract

Motivation
K-mers along with their frequency have served as an elementary building block for error correction, repeat detection, multiple sequence alignment, genome assembly, etc., attracting intensive studies in k-mer counting. However, the output of k-mer counters itself is large; very often, it is too large to fit into main memory, leading to highly narrowed usability.

Results
We introduce a novel idea of encoding k-mers as well as their frequency, achieving good memory saving and retrieval efficiency. Specifically, we propose a Bloom filter-like data structure to encode counted k-mers by coupled-bit arrays—one for k-mer representation and the other for frequency encoding. Experiments on five real datasets show that the average memory-saving ratio on all 31-mers is as high as 13.81 as compared with raw input, with 7 hash functions. At the same time, the retrieval time complexity is well controlled (effectively constant), and the false-positive rate is decreased by two orders of magnitude.

Availability and implementation
The source codes of our algorithm are available at github.com/lzhLab/kmcEx.

Supplementary information
Supplementary data are available at Bioinformatics online.
Maximizing Achievable Transmission Time in Cognitive Radio Networks Under Sensor-Aided Crowdsourced Spectrum Sensing
Authors: Almasaeid Hisham M 
Published: April 2019

Abstract
Spectrum-sensing as a service has been proposed and studied by many researchers over the past decade as a promising approach to support the viability of cognitive radio networks (CRNs). A spectrum-sensing service provider (SSP) provides information about spectrum occupancy to its clients that is generally more accurate than what clients can learn on their own. Two approaches are used by SSPs in their operation, the dedicated sensing infrastructure approach (sensor-aided CRN) and the crowdsensing approach. In this work, we assume a hybrid model where a dedicated sensing infrastructure is used along with crowdsensing. We study the tradeoff between sensing time paid by cognitive users to the SSP and their achievable transmission time. Our objective is to maximize the minimum achievable transmission time for any cognitive user in the network by carefully selecting the channels to be used. Two algorithms are proposed, one is based on the hill-climbing search algorithm (abbreviated HCA) and the other is a less optimal but faster greedy selection algorithm (abbreviated GSA). Results show that both HCA and GSA are within 3% of the optimal solution. Results also confirm that GSA is faster than HCA, while HCA outperforms GSA.
Genomic and mitochondrial evidence of ancient isolations and extreme introgression in the four-lined snake
Authors: Thanou Evanthia , Kornilios Panagiotis , Lymberakis Petros , Leaché Adam D 
Published: April 2019

AbstractComparing mitochondrial and genomic phylogenies is an essential tool for investigating speciation processes, because each genome carries different inheritance properties and evolutionary characteristics. Furthermore, mitonuclear discordance may arise from ecological adaptation, historic isolation, population size changes, and sex-biased dispersal. Closely related taxa are expected to experience gene flow; however, this may not be true for insular populations or populations isolated in refugia. The four-lined snake Elaphe quatuorlineata has a fragmented distribution, separating populations of the Italian and Balkan Peninsulas, whereas several insular Aegean populations of significantly smaller body size (Cyclades island group and Skyros Island, Greece) are currently considered distinct subspecies. We constructed the species-tree phylogeny of this species utilizing genome-wide single nucleotide polymorphisms and a gene-tree based on complete cytochrome b sequences, aiming to detect convergence and discrepancies between biparentally and maternally inherited genomes. Population structuring, phylogenetic patterns and migration events among geographically defined lineages supported our hypothesis of isolation in multiple sub-refugia. Where biogeographical barriers did not restrict subsequent dispersal, extensive genetic exchange occurred between mainland Balkan populations. This process has led to the mitochondrial sweep of an ancestral mitolineage that survived only in peripheral (East Greece) and insular populations (North Cyclades and Skyros). The Central Cyclades represent an ancient lineage for both molecular markers that emerged almost 3.3 Mya. Considering their distinct morphology, insular E. quatuorlineata populations should be the future focus of an extensive sampling, especially since the mitonuclear discordance observed in this species could be related to ecological adaptations, such as the island-dwarfism phenomenon.
A Transatlantic Secular Divide? The Representation of Religion in EU and US Foreign Policy
Authors: Jenichen Anne 
Published: April 2019

AbstractIt is a common—often stereotypical—presumption that Europe is secular and America religious. Differences in international religious freedom and religious engagement policies on both sides of the Atlantic seem to confirm this “cliché.” This article argues that to understand why it has been easier for American supporters to institutionalize these policies than for advocates in the EU, it is important to consider the discursive structures of EU and US foreign policies, which enable and constrain political language and behavior. Based on the analysis of foreign policy documents, produced by the EU and the United States in their relationship with six religiously diverse African and Asian states, the article compares how both international actors represent religion in their foreign affairs. The analysis reveals similarities in the relatively low importance that they attribute to religion and major differences in how they represent the contribution of religion to creating and solving problems in other states. In sum, the foreign policies of both international actors are based on a secular discursive structure, but that of the United States is much more accommodative toward religion, including Islam, than that of the EU.