bluuebunny/crossref_metadata_2025_split huggingface dataset:
Productivity, stability, and resilience of cool‐season perennial grasses used for rangeland revegetation
Authors: Robins Joseph G. , Waldron Blair L. , Jensen Kevin B. 
Published: February 2020

AbstractAn analysis of biomass and ground cover data collected from six rangeland sites in the Intermountain and Northern Great Plains areas of the United States from 2000 to 2004 was undertaken to characterize the productivity, stability, and resilience of cool‐season perennial grass species. Among the 13 included species, and the 48 cultivars, intermediate wheatgrass [Thinpyrum intermedium (Host) Barkworth & D.R. Dewey], tall wheatgrass [Thinpyrum elongatum (Host) D.R. Dewey], and to a lesser extent crested wheatgrass [Agropryon cristatum (L.) Gaertn. and A. desertorum (Fisch. ex Link) Schult.] possessed the greatest biomass productivity and ground cover. Basin wildrye [Leymus cinereus (Scribn. & Merr.) Á. Löve], thickspike wheatgrass [Elymus lanceolatus (Scribn. & J.G. Sm.) Gould], and bluebunch wheatgrass [Pseudoroegneria spicata (Pursh) Á. Löve] were least productive and stable. There were no differences among species or cultivars for biomass resilience and differences for ground cover resilience were limited. Overall, these three statistics provide an interesting comparison among rangeland species, but more long‐term datasets are necessary for greater inferences and more definitive conclusions.
MECP2 duplication syndrome in a patient from Cameroon
Authors: Tekendo‐Ngongang Cedrik , Dahoun Sophie , Nguefack Séraphin , Moix Isabelle , Gimelli Stefania , Zambo Huguette , Morris Michael A. , Sloan‐Béna Frédérique , Wonkam Ambroise 
Published: February 2020

AbstractMECP2 duplication syndrome (MDS; OMIM 300260) is an X‐linked neurodevelopmental disorder caused by nonrecurrent duplications of the Xq28 region involving the gene methyl‐CpG‐binding protein 2 (MECP2; OMIM 300005). The core phenotype of affected individuals includes infantile hypotonia, severe intellectual disability, very poor‐to‐absent speech, progressive spasticity, seizures, and recurrent infections. The condition is 100% penetrant in males, with observed variability in phenotypic expression within and between families. Features of MDS in individuals of African descent are not well known. Here, we describe a male patient from Cameroon, with MDS caused by an inherited 610 kb microduplication of Xq28 encompassing the genes MECP2, IRAK1, L1CAM, and SLC6A8. This report supplements the public data on MDS and contributes by highlighting the phenotype of this condition in affected individuals of African descent.
Prenatal diagnosis of cerebro‐oculo‐facio‐skeletal syndrome: Report of three fetuses and review of the literature
Authors: Le Van Quyen Pauline , Calmels Nadège , Bonnière Maryse , Chartier Suzanne , Razavi Féréchté , Chelly Jamel , El Chehadeh Salima , Baer Sarah , Boutaud Lucile , Bacrot Séverine , Obringer Cathy , Favre Romain , Attié‐Bitach Tania , Laugel Vincent , Antal Maria C. 
Published: February 2020

AbstractCerebro‐oculo‐facio‐skeletal syndrome (COFS) is a rare autosomal recessive neurodegenerative disease belonging to the family of DNA repair disorders, characterized by microcephaly, congenital cataracts, facial dysmorphism and arthrogryposis. Here, we describe the detailed morphological and microscopic phenotype of three fetuses from two families harboring ERCC5/XPG likely pathogenic variants, and review the five previously reported fetal cases. In addition to the classical features of COFS, the fetuses display thymus hyperplasia, splenomegaly and increased hematopoiesis. Microencephaly is present in the three fetuses with delayed development of the gyri, but normal microscopic anatomy at the supratentorial level. Microscopic anomalies reminiscent of pontocerebellar hypoplasia are present at the infratentorial level. In conclusion, COFS syndrome should be considered in fetuses when intrauterine growth retardation is associated with microcephaly, arthrogryposis and ocular anomalies. Further studies are needed to better understand XPG functions during human development.
Recent Advances in Total Synthesis of Bioactive Furo[3,2‐b]furanone Natural Products
Authors: Bhat Bilal A. , Rashid Showkat , Sengupta Saumitra , Mehta Goverdhan 
Published: February 2020

AbstractThe ubiquitous presence of highly oxygenated furo[3,2‐b]furanone fragments in diverse natural products with wide range of biological activities such as anti‐cancer, anti‐HIV, anti‐microbial activities, etc., has augmented their appeal both for synthetic and medicinal chemistry campaigns. Enticed by their potent biological activities and challenging polycyclic architecture, total synthesis of furo[3,2‐b]furanone natural products has witnessed intense activity in recent years with many notable achievements in the synthesis of structurally embellished family of bioactive metabolites such as plakortones, lactonamycines, schisanartanes, etc. While presenting a comprehensive account of post‐2000 syntheses of these natural products, through strategic and nuanced use of modern tools of organic synthesis, this review also aims to stimulate interest in exploring the diversity space around these natural products for newer applications.
ZnS Nanospheres for Optical Modulator in an Erbium‐Doped Fiber Laser
Authors: Liu Jie , Li Xiaohui , Feng Jiangjiang , Zheng Chuang , Wang Yamin , Wang Aocheng , Liu Xinfeng 
Published: February 2020

AbstractZinc sulfide (ZnS), which belongs to transition metal monochalcogenides, is a semiconductor material with wide direct band gap. It can potentially show some special applications (such as luminescence, phosphor, sensors, infrared window materials, photocatalysis) by changing the morphology, size, and crystal structure of semiconductor materials. However, ZnS nanospheres have not been studied as optical modulators until now. Herein, ZnS nanospheres are synthesized by the hydrothermal method and are used to realize optical modulators in an Er‐doped fiber laser. The evanescent field effect is utilized to incorporate the ZnS nanospheres on a tapered fiber. Furthermore, with the increase in pump power, the modulation interval gradually decreases to a minimum of 34.36 ns corresponding to the modulation frequency of 29.1 MHz, which is the highest modulation frequency to our knowledge in a ring cavity all‐fiber laser. These results demonstrate ZnS nanospheres together with the interaction of dispersion and nonlinearity in optical fibers can modulate the proposed lasers. This not only provides a new method for controlling the power and frequency of all optical modulators, but also marks an important step for ZnS materials in optics research and device applications.
A Stable All‐Thiophene‐Based Core‐Modified [38]Octaphyrin Diradicaloid: Conformation and Aromaticity Switch at Different Oxidation States
Authors: Ni Yong , Gopalakrishna Tullimilli Y. , Wu Shaofei , Wu Jishan 
Published: February 2020

AbstractA soluble and stable core‐modified [38]octaphyrin, MC‐T8, containing eight thiophene rings was synthesized by Yamamoto coupling followed by oxidative dehydrogenation. X‐ray crystallographic analysis revealed a nearly planar backbone, and the molecule is globally aromatic with a dominant 38π conjugation pathway. The dication MC‐T82+ is antiaromatic, and the backbone is distorted, with a different orientation of the thiophene rings. The tetracation MC‐T84+ becomes aromatic again, with a shallow‐bowl‐shaped geometry. Both the neutral compound and the dication demonstrated open‐shell diradical character with a small singlet–triplet energy gap (−2.70 kcal mol−1 for MC‐T8 and −3.78 kcal mol−1 for MC‐T82+), and they are stable owing to effective spin delocalization.
Supramolecular Fluorescence Resonance Energy Transfer in Nucleobase‐Modified Fluorogenic RNA Aptamers
Authors: Steinmetzger Christian , Bäuerlein Carmen , Höbartner Claudia 
Published: February 2020

AbstractRNA aptamers form compact tertiary structures and bind their ligands in specific binding sites. Fluorescence‐based strategies reveal information on structure and dynamics of RNA aptamers. Herein, we report the incorporation of the universal emissive nucleobase analog 4‐cyanoindole into the fluorogenic RNA aptamer Chili, and its application as a donor for supramolecular FRET to the bound ligands DMHBI+ or DMHBO+. The photophysical properties of the new nucleobase–ligand‐FRET pair revealed structural restraints for the overall RNA aptamer organization and identified nucleotide positions suitable for FRET‐based readout of ligand binding. This strategy is generally suitable for binding‐site mapping and may also be applied for responsive aptamer devices.
A Modular Synthetic Strategy for Functional Macrocycles
Authors: Xu Kaidi , Zhang Zhi‐Yuan , Yu Chengmao , Wang Bin , Dong Ming , Zeng Xianqiang , Gou Rui , Cui Lei , Li Chunju 
Published: February 2020

AbstractReported here is a molecule‐Lego synthetic strategy for macrocycles with functional skeletons, involving one‐pot and high‐yielding condensation between bis(2,4‐dimethoxyphenyl)arene monomers and paraformaldehyde. By changing the blocks, variously functional units (naphthalene, pyrene, anthraquinone, porphyrin, etc.) can be conveniently introduced into the backbone of macrocycles. Interestingly, the macrocyclization can be tuned by the geometrical configuration of monomeric blocks. Linear (180°) monomer yield cyclic trimers and pentamers, while V‐shaped (120°, 90° and 60°) monomers tend to form dimers. More significantly, even heterogeneous macrocycles are obtained in moderate yield by co‐oligomerization of different monomers. This series of macrocycles have the potential to be prosperous in the near future.
Synthesis of epichlorohydrin from 1,3‐dichlorohydrin with solid catalysts using γ‐Al2O3 as carrier material
Authors: Zhang Rong , Yang Huimin , Li Fuxiang , Ma Yao 
Published: February 2020

AbstractAlkaline earth metal‐based catalysts applied in the process of dichlorohydrin cyclization into epichlorohydrin were studied. A series of solid catalysts were prepared by the equivalent‐volume impregnation method using γ‐Al2O3 as a carrier, whereas nitrates and chlorides of the three alkaline earth metals (Mg, Ca, and Ba) were employed as precursors. Their catalytic performance was investigated and compared, taking into account the main factors influencing the catalytic efficiency, such as X‐ray diffraction (XRD), N2 adsorption–desorption, energy dispersive spectrometry (EDS) coupled with TEM, and CO2 temperature‐programmed desorption (CO2‐TPD). The results have shown that the specific surface area and the number of active base sites are the main factors that are affecting the catalytic efficiency. Among the series of as‐prepared catalysts, 10BaO/γ‐Al2O3 had improved catalytic performance. Based on the obtained results for the characterization of catalysts, the increased catalytic activity could be mainly attributed to the increase in base strength resulting from BaO loading onto the surface of γ‐Al2O3. Under optimized conditions, 98.4% conversion of 1,3‐DCH and approximately 90% of ECH selectivity were achieved using 10BaO/γ‐Al2O3 with a reaction temperature of 270°C. During the reaction process, the catalytic activity of 10BaO/γ‐Al2O3 remained consistently high, and its catalytic stability was excellent.
Choline ameliorates ethanol induced alterations in tyrosine phosphorylation and distribution in detergent‐resistant membrane microdomains of L1 cell adhesion molecule in vivo
Authors: Davis Natalie L. , Tang Ningfeng , He Min , Lee Daniel , Bearer Cynthia F. 
Published: February 2020

AbstractBackgroundExposure to ethanol during pregnancy is the cause of fetal alcohol spectrum disorder. The function of L1 cell adhesion molecule (L1), critical for proper brain development, is dependent on detergent‐resistant membrane microdomains (DRM). Ethanol at low concentrations disrupts L1 function measured by inhibition of downstream signaling and alterations in L1‐DRM distribution in cerebellum in vivo and in cerebellar granule neurons (CGN) in vitro. We have previously shown that choline pretreatment of CGN partially prevents ethanol toxicity through improving L1 function in vitro. Here we show that choline supplementation reduces the impact of ethanol on L1 in cerebellum in vivo.MethodsPregnant rat dams were placed on choline free diet on gestational Day 5 (G5). Pups were treated with saline or choline from postnatal day (P) 1–5. On P5, pups were intubated twice 2 hr apart with ethanol or Intralipid® for a total dose of 6 g/kg/d and sacrificed 1 hr after the last intubation. The cerebella were harvested and L1 phosphorylation/dephosphorylation status and distribution in DRM were analyzed.ResultsEthanol reduced L1 tyrosine phosphorylation and L1‐Y1176 dephosphorylation in cerebella, and caused an increase in the percent of L1 in DRM. Choline supplementation of pups reduced the ethanol‐induced changes in L1 phosphorylation status and ameliorated ethanol‐induced redistribution of L1 into DRM.ConclusionCholine supplementation before an acute dose of ethanol ameliorates changes in L1 in vivo.
Construction and assessment of prediction rules for binary outcome in the presence of missing predictor data using multiple imputation and cross‐validation: Methodological approach and data‐based evaluation
Authors: Mertens Bart J. A. , Banzato Erika , de Wreede Liesbeth C. 
Published: February 2020

AbstractWe investigate calibration and assessment of predictive rules when missing values are present in the predictors. Our paper has two key objectives. The first is to investigate how the calibration of the prediction rule can be combined with use of multiple imputation to account for missing predictor observations. The second objective is to propose such methods that can be implemented with current multiple imputation software, while allowing for unbiased predictive assessment through validation on new observations for which outcome is not yet available.We commence with a review of the methodological foundations of multiple imputation as a model estimation approach as opposed to a purely algorithmic description. We specifically contrast application of multiple imputation for parameter (effect) estimation with predictive calibration. Based on this review, two approaches are formulated, of which the second utilizes application of the classical Rubin's rules for parameter estimation, while the first approach averages probabilities from models fitted on single imputations to directly approximate the predictive density for future observations. We present implementations using current software that allow for validation and estimation of performance measures by cross‐validation, as well as imputation of missing data in predictors on the future data where outcome is missing by definition.To simplify, we restrict discussion to binary outcome and logistic regression throughout. Method performance is verified through application on two real data sets. Accuracy (Brier score) and variance of predicted probabilities are investigated. Results show substantial reductions in variation of calibrated probabilities when using the first approach.
Extracellular laccase from Monilinia fructicola: isolation, primary characterization and application
Authors: Demkiv Olga M. , Gayda Galina Z. , Broda Daniel , Gonchar Mykhailo V. 
Published: February 2020

AbstractLaccases are enzymes belonging to the family of blue copper oxidases. Due to their broad substrate specificity, they are widely used in many industrial processes and environmental bioremediations for removal of a large number of pollutants. During last decades, laccases attracted scientific interest also as highly promising enzymes to be used in bioanalytics. The aim of this study is to obtain a highly purified laccase from an efficient fungal producer and to demonstrate the applicability of this enzyme for analytics and bioremediation. To select the best microbial source of laccase, a screening of fungal strains was carried out and the fungus Monilinia fructicola was chosen as a producer of an extracellular enzyme. Optimal cultivation conditions for the highest yield of laccase were established; the enzyme was purified by a column chromatography and partially characterized. Molecular mass of the laccase subunit was determined to be near 35 kDa; the optimal pH ranges for the highest activity and stability are 4.5–5.0 and 3.0–5.0, respectively; the optimal temperature for laccase activity is 30°C. Laccase preparation was successfully used as a biocatalyst in the amperometric biosensor for bisphenol A assay and in the bioreactor for bioremediation of some xenobiotics.
Design and synthesis of chiral spirobifluorenes
Authors: Ozcelik Ani , Peña‐Gallego María de los Ángeles , Pereira‐Cameselle Raquel , Alonso‐Gómez J. Lorenzo 
Published: February 2020

AbstractChiroptical spectroscopic methods serve as a practical tool for the structural characterization of chiral systems based on the interaction with polarized light. The higher sensitivity of these methods, compared with their achiral counterparts, not only enables the determination of absolute configuration and conformational preferences, but also supramolecular interactions may be monitored. In order to expand the applicability of chiroptical systems, the development of functional materials exhibiting intense chiroptical responses is essential. As a proof of principle, we previously constructed chiroptical interfaces via thioacetate‐derivatized allenes. Because of the photoisomerization issues associated with allenes, we have recently proposed their replacement by spirobifluorenes to achieve robust chiroptical systems. Thus, we hereby present the design and synthesis of chiral spirobifluorenes bearing thioacetates suitable for suface functionalization.
Alkali and Alkaline Earth Metal Ions Complexes with a Partial Peptide of the Selectivity Filter in K+ Channels Studied by a Cold Ion Trap Infrared Spectroscopy
Authors: Otsuka Remina , Hirata Keisuke , Sasaki Yuta , Lisy James M. , Ishiuchi Shun‐ichi , Fujii Masaaki 
Published: February 2020

AbstractThe infrared (IR) spectra of alkali and alkaline earth metal ion complexes with the Ac‐Tyr‐NHMe (GYG) peptide have been measured by laser photodissociation in a cold ion trap coupled with an electrospray mass spectrometer. The GYG peptide corresponds to a portion of the ion selectivity filter in the KcsA K+ channel that allows K+ to pass, but blocks Na+ even though it has a smaller ionic radius than K+. This current study extends a previous investigation on Na+ and K+ to the entire set of alkali metaI ions and alkaline earth dications. IR‐IR hole‐burning (IR2 dip) spectroscopy has established the coexistence of several conformers of the GYG‐metal ion complexes. The structures of the conformers were assigned by comparison between the isomer‐selected IR spectra and theoretical IR spectra obtained from quantum chemical calculations. It was found that the structure of the dominant conformer correlates with the ability of the ion to permeate through the K+ channel.
Inter‐individual variation of the urinary steroid profiles in Swedish and Norwegian athletes
Authors: Mullen Jenny , Bækken Lasse Vestli , Törmäkangas Timo , Ekström Lena , Ericsson Magnus , Hullstein Ingunn R. , Schulze Jenny J. 
Published: February 2020

AbstractThe steroidal module of the Athlete Biological Passport (ABP) aims to detect doping with endogenous steroids, e.g. testosterone (T), by longitudinally monitoring several biomarkers. These biomarkers are ratios combined into urinary concentrations of testosterone and metabolically related steroids. However, it is evident after 5 years of monitoring steroid passports that there are large variations in the steroid ratios complicating its interpretation. In this study, we used over 11000 urinary steroid profiles from Swedish and Norwegian athletes to determine both the inter‐ and intra‐individual variations of all steroids and ratios in the steroidal passport. Furthermore, we investigated if the inter‐individual variations could be associated with factors such as gender, type of sport, age, time of day, time of year, and if the urine was collected in or out of competition. We show that there are factors reported in today's doping tests that significantly affect the steroid profiles. The factors with the largest influence on the steroid profile were the type of sport classification that the athlete belonged to as well as whether the urine was collected in or out of competition. There were also significant differences based on what time of day and time of year the urine sample was collected. Whether these significant changes are relevant when longitudinally monitoring athletes in the steroidal module of the ABP should be evaluated further.
Temporal variation in the roles of exotic and native plant species in plant–pollinator networks
Authors: Vitt Pati , Havens Kayri , Jolls Claudia L. , Knight Tiffany M. 
Published: February 2020

AbstractThe role of individual plant species, including those that are rare or invasive, in the structure of plant–pollinator networks will depend on how connected the plants are to pollinator species and when they flower. Plant species visited by a high diversity of pollinators that visit few other species during a particular time period are thought to provide high value to the insect community. Here, we examined the role of plant species in a plant–pollinator network across the entire flowering season and across dune and adjacent woodland habitats in Wisconsin,USA. We found strong turnover of plants, pollinators, and their interactions in time and space. Both native and exotic species play important structural roles in plant–pollinator networks. Simulations reveal that the loss of the early‐flowering rare plant,Cirsium pitcheri, would result in a disproportionate loss of pollinator species. Furthermore, the critical role that this species plays in the network is not replaced by its exotic relative,Centaurea stoebe. Our research demonstrates that consideration of temporal and spatial variability in networks allows for critical plant species to be identified within a plant–pollinator network that might otherwise be overlooked.