bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transition metal dichalcogenides bilayer single crystals by reverse-flow chemical vapor epitaxy
Authors: Zhang Xiumei , Nan Haiyan , Xiao Shaoqing , Wan Xi , Gu Xiaofeng , Du Aijun , Ni Zhenhua , Ostrikov Kostya 
Published: February 2019

AbstractEpitaxial growth of atomically thin two-dimensional crystals such as transition metal dichalcogenides remains challenging, especially for producing large-size transition metal dichalcogenides bilayer crystals featuring high density of states, carrier mobility and stability at room temperature. Here we achieve in epitaxial growth of the second monolayer from the first monolayer by reverse-flow chemical vapor epitaxy and produce high-quality, large-size transition metal dichalcogenides bilayer crystals with high yield, control, and reliability. Customized temperature profiles and reverse gas flow help activate the first layer without introducing new nucleation centers leading to near-defect-free epitaxial growth of the second layer from the existing nucleation centers. A series of bilayer crystals including MoS2 and WS2, ternary Mo1−xWxS2 and quaternary Mo1−xWxS2(1−y)Se2y are synthesized with variable structural configurations and tunable electronic and optical properties. The robust, potentially universal approach for the synthesis of large-size transition metal dichalcogenides bilayer single crystals is highly-promising for fundamental studies and technological applications.
−60 °C solution synthesis of atomically dispersed cobalt electrocatalyst with superior performance
Authors: Huang Kai , Zhang Le , Xu Ting , Wei Hehe , Zhang Ruoyu , Zhang Xiaoyuan , Ge Binghui , Lei Ming , Ma Jing-Yuan , Liu Li-Min , Wu Hui 
Published: February 2019

AbstractTemperature can govern morphologies, structures and properties of products from synthesis in solution. A reaction in solution at low temperature may result in different materials than at higher temperature due to thermodynamics and kinetics of nuclei formation. Here, we report a low-temperature solution synthesis of atomically dispersed cobalt in a catalyst with superior performance. By using a water/alcohol mixed solvent with low freezing point, liquid-phase reduction of a cobalt precursor with hydrazine hydrate is realized at −60 °C. A higher energy barrier and a sluggish nucleation rate are achieved to suppress nuclei formation; thus atomically dispersed cobalt is successfully obtained in a catalyst for oxygen reduction with electrochemical performance superior to that of a Pt/C catalyst. Furthermore, the atomically dispersed cobalt catalyst is applied in a microbial fuel cell to obtain a high maximum power density (2550 ± 60 mW m−2) and no current drop upon operation for 820 h.
Targets of complement-fixing antibodies in protective immunity against malaria in children
Authors: Reiling Linda , Boyle Michelle J. , White Michael T. , Wilson Danny W. , Feng Gaoqian , Weaver Rupert , Opi D. Herbert , Persson Kristina E. M. , Richards Jack S. , Siba Peter M. , Fowkes Freya J. I. , Takashima Eizo , Tsuboi Takafumi , Mueller Ivo , Beeson James G. 
Published: February 2019

AbstractAntibodies against P. falciparum merozoites fix complement to inhibit blood-stage replication in naturally-acquired and vaccine-induced immunity; however, specific targets of these functional antibodies and their importance in protective immunity are unknown. Among malaria-exposed individuals, we show that complement-fixing antibodies to merozoites are more strongly correlated with protective immunity than antibodies that inhibit growth quantified using the current reference assay for merozoite vaccine evaluation. We identify merozoite targets of complement-fixing antibodies and identify antigen-specific complement-fixing antibodies that are strongly associated with protection from malaria in a longitudinal study of children. Using statistical modelling, combining three different antigens targeted by complement-fixing antibodies could increase the potential protective effect to over 95%, and we identify antigens that were common in the most protective combinations. Our findings support antibody-complement interactions against merozoite antigens as important anti-malaria immune mechanisms, and identify specific merozoite antigens for further evaluation as vaccine candidates.
Age-associated Impairment of the Mucus Barrier Function is Associated with Profound Changes in Microbiota and Immunity
Authors: Sovran Bruno , Hugenholtz Floor , Elderman Marlies , Van Beek Adriaan A. , Graversen Katrine , Huijskes Myrte , Boekschoten Mark V. , Savelkoul Huub F. J. , De Vos Paul , Dekker Jan , Wells Jerry M. 
Published: February 2019

AbstractAging significantly increases the vulnerability to gastrointestinal (GI) disorders but there are few studies investigating the key factors in aging that affect the GI tract. To address this knowledge gap, we used 10-week- and 19-month-old litter-mate mice to investigate microbiota and host gene expression changes in association with ageing. In aged mice the thickness of the colonic mucus layer was reduced about 6-fold relative to young mice, and more easily penetrable by luminal bacteria. This was linked to increased apoptosis of goblet cells in the upper part of the crypts. The barrier function of the small intestinal mucus was also compromised and the microbiota were frequently observed in contact with the villus epithelium. Antimicrobial Paneth cell factors Ang4 and lysozyme were expressed in significantly reduced amounts. These barrier defects were accompanied by major changes in the faecal microbiota and significantly decreased abundance of Akkermansia muciniphila which is strongly and negatively affected by old age in humans. Transcriptomics revealed age-associated decreases in the expression of immunity and other genes in intestinal mucosal tissue, including decreased T cell-specific transcripts and T cell signalling pathways. The physiological and immunological changes we observed in the intestine in old age, could have major consequences beyond the gut.
Effects of Land cover change on Great Apes distribution at the Lobéké National Park and its surrounding Forest Management Units, South-East Cameroon. A 13 year time series analysis
Authors: Yuh Yisa Ginath , Dongmo Zacharie N. , N’Goran Paul K. , Ekodeck Herbert , Mengamenya Achile , Kuehl Hjalmar , Sop Tenekwetche , Tracz Wiktor , Agunbiade Michael , Elvis Tangwa 
Published: February 2019

AbstractUnderstanding the effects of land cover change on wildlife distribution is very important for resource management and conservation planning. This paper aimed at detecting the effects of land cover change on great apes distribution at the Lobéké National Park and its bounded forest management units (FMUs). Data on great ape nests were collected in the field for the years 2001 and 2014 through distance sampling with line transects. Landsat TM images of South-East Cameroon for the years 2001 and 2014 were acquired from earth explorer and corrected atmospherically for proper visualization. An area of interest comprising the Lobéké National Park and its FMUs was extracted for classification and change detection. A comparison in great apes nest distribution and change per land cover change category was done for both years through point pattern analysis, whereas a time series analysis of the detected land cover change impacts on great apes nest distribution for a period of 13 years was modeled using logistic growth and regression equations in Vensim 7.2. The results could illustrate that, as land cover changes from one cover type in 2001 to another in 2014, increases or decreases in great apes nests were observed within each changed area.
Analysis of Corneal Spherical Aberrations in Cataract Patients with High Myopia
Authors: Zhang Min , Qian Dongjin , Jing Qinghe , Chen Jiahui , Jiang Yongxiang 
Published: February 2019

AbstractTo evaluate the corneal spherical aberrations in cataract patients with and without high myopia, we conducted a retrospective case series of 502 cataract eyes with high myopia and 1500 age-related cataract eyes and measure their corneal biometric data and axial length using Pentacam and IOLMaster. Both the anterior and total corneal primary spherical aberrations were lower in the high myopia group than that in the control group (0.317 ± 0.215 vs 0.338 ± 0.148 μm, P = 0.043; and 0.281 ± 0.207 vs 0.314 ± 0.153 μm, P < 0.001). The incidence of eyes with negative total corneal primary spherical aberration increased as axial length increased in the high myopia group, and the overall incidence was higher in the high myopia group than that in the control group (2.59% vs 1.47%). These were mainly contributed to the younger age of cataract patients with high myopia (55.76 ± 13.10 vs 60.18 ± 15.72 years, P < 0.001), along with the positive correlations between age and anterior and total corneal primary spherical aberrations. In clinical practice, an aspheric IOL with a low negative or zero primary spherical aberration is recommended for cataract patients with high myopia. Negative total ocular primary spherical aberrations resulting from aspheric IOL implantation should be avoided in extremely high myopic eyes.
Modelling the current fractional cover of an invasive alien plant and drivers of its invasion in a dryland ecosystem
Authors: Shiferaw Hailu , Schaffner Urs , Bewket Woldeamlak , Alamirew Tena , Zeleke Gete , Teketay Demel , Eckert Sandra 
Published: February 2019

AbstractThe development of spatially differentiated management strategies against invasive alien plant species requires a detailed understanding of their current distribution and of the level of invasion across the invaded range. The objectives of this study were to estimate the current fractional cover gradient of invasive trees of the genus Prosopis in the Afar Region, Ethiopia, and to identify drivers of its invasion. We used seventeen explanatory variables describing Landsat 8 image reflectance, topography, climate and landscape structures to model the current cover of Prosopis across the invaded range using the random forest (RF) algorithm. Validation of the RF algorithm confirmed high model performance with an accuracy of 92% and a Kappa-coefficient of 0.8. We found that, within 35 years after its introduction, Prosopis has invaded approximately 1.17 million ha at different cover levels in the Afar Region (12.3% of the surface). Normalized difference vegetation index (NDVI) and elevation showed the highest explanatory power among the 17 variables, in terms of both the invader’s overall distribution as well as areas with high cover. Villages and linear landscape structures (rivers and roads) were found to be more important drivers of future Prosopis invasion than environmental variables, such as climate and topography, suggesting that Prosopis is likely to continue spreading and increasing in abundance in the case study area if left uncontrolled. We discuss how information on the fractional cover and the drivers of invasion can help in developing spatially-explicit management recommendations against a target invasive plant species.
Spectroscopy and SEM imaging reveal endosymbiont-dependent components changes in germinating kernel through direct and indirect coleorhiza-fungus interactions under stress
Authors: Vujanovic Vladimir , Kim Seon Hwa , Lahlali Rachid , Karunakaran Chithra 
Published: February 2019

AbstractIn the present study, FTIR spectroscopy and hyperspectral imaging was introduced as a non-destructive, sensitive-reliable tool for assessing the tripartite kernel-fungal endophyte environment interaction. Composition of coleorhizae of Triticum durum was studied under ambient and drought stress conditions. The OH-stretch IR absorption spectrum suggests that the water-deficit was possibly improved or moderated by kernel’s endophytic partner. The OH-stretch frequency pattern coincides with other (growth and stress) related molecular changes. Analysis of lipid (3100–2800 cm−1) and protein (1700–1550 cm−1) regions seems to demonstrate that drought has a positive impact on lipids. The fungal endosymbiont direct contact with kernel during germination had highest effect on both lipid and protein (Amide I and II) groups, indicating an increased stress resistance in inoculated kernel. Compared to the indirect kernel-fungus interaction and to non-treated kernels (control), direct interaction produced highest effect on lipids. Among treatments, the fingerprint region (1800–800 cm−1) and SEM images indicated an important shift in glucose oligosaccharides, possibly linked to coleorhiza-polymer layer disappearance. Acquired differentiation in coleorhiza composition of T. durum, between ambient and drought conditions, suggests that FTIR spectroscopy could be a promising tool for studying endosymbiont-plant interactions within a changing environment.
The differences of lipid profiles between only children and children with siblings: A national survey in China
Authors: Cai Li , Ma Bingjie , Lin Lizi , Chen Yajun , Yang Wenhan , Ma Jun , Jing Jin 
Published: February 2019

AbstractWith the increasing number of the one-child family, it is important to investigate whether the only-child status is associated with dyslipidemia. Among a national sample of 65,347 Chinese children aged 6–17 years, 16,100 lipid profiles were available. Children’s height, weight, total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were measured. In comparison to children with siblings, only children (OC) were more likely to be boys and live in urban areas. OC had less physical activity, less fried food intake, but more meat and dairy intakes. OC had significantly higher levels of TC (3.97 ± 0.78 vs. 3.89 ± 0.77) and LDL-C (2.12 ± 0.65 vs. 2.06 ± 0.64) in the overall group, and also in the subgroups of rural boys and girls. The prevalence of hyper-TC (5.48% vs. 4.43%) and hyper-LDL-C (3.97% vs. 2.96%) were significantly higher in OC than their counterparts. Furthermore, we found higher odds of hyper-LDL-C [1.43 (1.12, 1.83)] in OC after adjustments. In the subgroup analysis, only-child status was associated with increased risk of hyper-TC [1.86 (1.06, 3.26)] and hyper-LDL-C [2.65 (1.14, 6.16)] among rural boys, and hyper-LDL-C among rural girls [2.20 (1.14, 4.22)]. In conclusion, higher levels of TC and LDL-C were found in OC especially for rural children. Being an only-child was associated with increased risk of hyper-LDL-C.
Clustering patterns in efficiency and the coming-of-age of the cryptocurrency market
Authors: Sigaki Higor Y. D. , Perc Matjaž , Ribeiro Haroldo V. 
Published: February 2019

AbstractThe efficient market hypothesis has far-reaching implications for financial trading and market stability. Whether or not cryptocurrencies are informationally efficient has therefore been the subject of intense recent investigation. Here, we use permutation entropy and statistical complexity over sliding time-windows of price log returns to quantify the dynamic efficiency of more than four hundred cryptocurrencies. We consider that a cryptocurrency is efficient within a time-window when these two complexity measures are statistically indistinguishable from their values obtained on randomly shuffled data. We find that 37% of the cryptocurrencies in our study stay efficient over 80% of the time, whereas 20% are informationally efficient in less than 20% of the time. Our results also show that the efficiency is not correlated with the market capitalization of the cryptocurrencies. A dynamic analysis of informational efficiency over time reveals clustering patterns in which different cryptocurrencies with similar temporal patterns form four clusters, and moreover, younger currencies in each group appear poised to follow the trend of their ‘elders’. The cryptocurrency market thus already shows notable adherence to the efficient market hypothesis, although data also reveals that the coming-of-age of digital currencies is in this regard still very much underway.
Deaf moths employ acoustic Müllerian mimicry against bats using wingbeat-powered tymbals
Authors: O’Reilly Liam J. , Agassiz David J. L. , Neil Thomas R. , Holderied Marc W. 
Published: February 2019

AbstractEmitting ultrasound upon hearing an attacking bat is an effective defence strategy used by several moth taxa. Here we reveal how Yponomeuta moths acquire sophisticated acoustic protection despite being deaf themselves and hence unable to respond to bat attacks. Instead, flying Yponomeuta produce bursts of ultrasonic clicks perpetually; a striated patch in their hind wing clicks as the beating wing rotates and bends. This wing structure is strikingly similar to the thorax tymbals with which arctiine moths produce their anti-bat sounds. And indeed, Yponomeuta sounds closely mimic such arctiine signals, revealing convergence in form and function. Because both moth taxa contain noxious compounds, we conclude they are mutual Müllerian acoustic mimics. Yponomeuta’s perpetual clicking would however also attract bat predators. In response, their click amplitude is reduced and affords acoustic protection just as far as required, matching the distance over which bat biosonar would pick up Yponomeuta echoes anyway – advanced acoustic defences for a deaf moth.
Augmenting central arterial stiffness following eradication of HCV by direct acting antivirals in advanced fibrosis patients
Authors: Cheng Pin-Nan , Chen Ju-Yi , Chiu Yen-Cheng , Chiu Hung-Chih , Tsai Liang-Miin 
Published: February 2019

AbstractChronic hepatitis C (CHC) is strongly associated with risks of cardiovascular diseases. The impact of direct acting antiviral (DAA) therapy on central blood pressure remains unclear. This investigation evaluates changes in central blood pressure following DAA therapy. One hundred and two DAA-treated patients were prospectively enrolled. Lipid profiles and pulse wave analysis of brachial artery by cuff sphygmomanometry including augmentation index (AIx), a parameter of central artery stiffness, were evaluated. All of the 102 patients achieved sustained virological response (SVR12). Cholesterol and LDL significantly increased following SVR12. Along with lipid changes, significantly higher central diastolic pressure (78.2 ± 14.2 mm Hg at baseline vs. 83.3 ± 13.9 mm Hg at SVR12, p = 0.011) and AIx (33.0 ± 12.7% at baseline vs. 36.9 ± 12.9% at SVR12, p = 0.012) were only observed in the advanced fibrosis patients. Co-morbid diseases, including hypertension (33.4 ± 13.0% vs. 39.7 ± 12.6%, p = 0.003), abnormal waist circumference (33.8 ± 12.2% vs. 38.0 ± 13.2%, p = 0.027), and metabolic syndrome (34.5 ± 12.1% vs. 39.0 ± 11.2%, p = 0.043) were associated with augmented AIx upon SVR12. The augmented central artery stiffness following viral eradication by DAA therapy may raise the concern of short-term cardiovascular risk in CHC patients.
Defining the genes for the final steps in biosynthesis of the complex polyketide antibiotic mupirocin by Pseudomonas fluorescens NCIMB10586
Authors: Connolly Jack A. , Wilson Amber , Macioszek Malgorzata , Song Zhongshu , Wang Luoyi , Mohammad Hadi H. , Yadav Mukul , di Martino Maura , Miller Claire E. , Hothersall Joanne , Haines Anthony S. , Stephens Elton R. , Crump Matthew P. , Willis Christine L. , Simpson Thomas J. , Winn Peter J. , Thomas Christopher M. 
Published: February 2019

AbstractThe mupirocin trans-AT polyketide synthase pathway, provides a model system for manipulation of antibiotic biosynthesis. Its final phase involves removal of the tertiary hydroxyl group from pseudomonic acid B, PA-B, producing the fully active PA-A in a complex series of steps. To further clarify requirements for this conversion, we fed extracts containing PA-B to mutants of the producer strain singly deficient in each mup gene. This additionally identified mupM and mupN as required plus the sequence but not enzymic activity of mupL and ruled out need for other mup genes. A plasmid expressing mupLMNOPVCFU + macpE together with a derivative of the producer P. fluorescens strain NCIMB10586 lacking the mup cluster allowed conversion of PA-B to PA-A. MupN converts apo-mAcpE to holo-form while MupM is a mupirocin-resistant isoleucyl tRNA synthase, preventing self-poisoning. Surprisingly, the expression plasmid failed to allow the closely related P. fluorescens strain SBW25 to convert PA-B to PA-A.
Characterisation of N-glycans in the epithelial-like tissue of the rat cochlea
Authors: Nonomura Yoriko , Sawamura Seishiro , Hanzawa Ken , Nishikaze Takashi , Sekiya Sadanori , Higuchi Taiga , Nin Fumiaki , Uetsuka Satoru , Inohara Hidenori , Okuda Shujiro , Miyoshi Eiji , Horii Arata , Takahashi Sugata , Natsuka Shunji , Hibino Hiroshi 
Published: February 2019

AbstractMembrane proteins (such as ion channels, transporters, and receptors) and secreted proteins are essential for cellular activities. N-linked glycosylation is involved in stability and function of these proteins and occurs at Asn residues. In several organs, profiles of N-glycans have been determined by comprehensive analyses. Nevertheless, the cochlea of the mammalian inner ear, a tiny organ mediating hearing, has yet to be examined. Here, we focused on the stria vascularis, an epithelial-like tissue in the cochlea, and characterised N-glycans by liquid chromatography with mass spectrometry. This hypervascular tissue not only expresses several ion transporters and channels to control the electrochemical balance in the cochlea but also harbours different transporters and receptors that maintain structure and activity of the organ. Seventy-nine N-linked glycans were identified in the rat stria vascularis. Among these, in 55 glycans, the complete structures were determined; in the other 24 species, partial glycosidic linkage patterns and full profiles of the monosaccharide composition were identified. In the process of characterisation, several sialylated glycans were subjected sequentially to two different alkylamidation reactions; this derivatisation helped to distinguish α2,3-linkage and α2,6-linkage sialyl isomers with mass spectrometry. These data should accelerate elucidation of the molecular architecture of the cochlea.
Design of training populations for selective phenotyping in genomic prediction
Authors: Akdemir Deniz , Isidro-Sánchez Julio 
Published: February 2019

AbstractPhenotyping is the current bottleneck in plant breeding, especially because next-generation sequencing has decreased genotyping cost more than 100.000 fold in the last 20 years. Therefore, the cost of phenotyping needs to be optimized within a breeding program. When designing the implementation of genomic selection scheme into the breeding cycle, breeders need to select the optimal method for (1) selecting training populations that maximize genomic prediction accuracy and (2) to reduce the cost of phenotyping while improving precision. In this article, we compared methods for selecting training populations under two scenarios: Firstly, when the objective is to select a training population set (TRS) to predict the remaining individuals from the same population (Untargeted), and secondly, when a test set (TS) is first defined and genotyped, and then the TRS is optimized specifically around the TS (Targeted). Our results show that optimization methods that include information from the test set (targeted) showed the highest accuracies, indicating that apriori information from the TS improves genomic predictions. In addition, predictive ability enhanced especially when population size was small which is a target to decrease phenotypic cost within breeding programs.