bluuebunny/crossref_metadata_2025_split huggingface dataset:
Legacy of eight‐year cover cropping on mycorrhizae, soil, and plants
Authors: García-González Irene , Quemada Miguel , Gabriel José Luis , Alonso-Ayuso María , Hontoria Chiquinquirá 
Published: September 2018

AbstractCover crops (CCs) provide ecosystem services to agricultural systems by soil health enhancement. However, the long‐term legacy of CCs on arbuscular mycorrhizal fungi (AMF) and subsequent main crop performance is unclear. The main objective of this work was to assess the 8‐year legacy of CCs on AMF activity and several soil and plant parameters during a subsequent maize (Zea mays L.) crop. The study was conducted in a field experiment established in 2006 under Mediterranean climate. Winter treatments were fallow and two CCs, barley (Hordeum vulgare L.) and vetch (Vicia sativa L.). We chose four sampling dates during maize development to evaluate the effect of CCs on AMF over time. Compared with fallow treatment, barley CC increased mycorrhizal colonization by 7%, the hyphae length by 39–124%, and AMF spores by 48–87%. However, contrary to expectations, vetch CC did not have any effect on AMF. Overall, earlier sampling dates better displayed treatment differences. Mycorrhizal colonization percentage demonstrated time‐sensitive values, whereas other AMF parameters (hyphae length, AMF spores) better maintained treatment differences over time. Mycorrhizal stimulation after barley increased maize shoot P concentration but shoot N was not increased despite the N deficit. Soil water stable aggregates were enhanced by barley CC (25–51% higher than fallow), notably related to the length of hyphae, AMF spores and glomalin content. Promotion of soil aggregation, nutritional state and plant height by CCs did not translate into maize yield increments. The main benefits of introducing CCs were related to the enhancement of soil quality and nutrient supply rather than to an increased yield of the following maize crop.
High‐resolution reconstruction of 8.2‐ka BP event documented in Père Noël cave, southern Belgium
Authors: Allan M. , Fagel N. , van der Lubbe H. J. L. , Vonhof H. B. , Cheng H. , Edwards R. Lawrence , Verheyden S. 
Published: September 2018

ABSTRACTA distinct shift in δ18O, δ13C and trace element contents of the Père Noël (PN) stalagmite from southern Belgium revealed an abrupt climatic anomaly at 8.13 ± 0.03 ka BP (before present = before 1950 AD). This anomaly is characterized by a maximum drop in the δ18O (−1.4‰ compared the mean) between 8.13 and 8.10 ka BP (±0.03). This drop of δ18O coincides with a decrease in δ13C and trace element (Sr, Ba and Mg) concentrations suggesting drier conditions. Our precise chronology provides the timing of the outburst of proglacial lakes Agassiz and Ojibway that caused the δ18O, δ13C and trace elemental anomalies at 8.13–8.10 ± 0.03 ka BP, which corresponds to the 8.2‐ka BP event. The PN stalagmite bears δ18O values in fluid inclusions that covary with the δ18O values in calcite, suggesting that the speleothem calcite δ18O primarily reflects variations in the rainfall δ18O. Comparison of the PN record with different marine and terrestrial archives during the 8.2‐ka BP event shows a good agreement in timing and duration, suggesting that the PN speleothem can be regarded as a valuable proxy to better understand the 8.2‐ka BP event.
Hydrolysis Activity of Pyloric Cecal Enterocytes of Brown Trout (Salmo trutta) toward Monoacylglycerol and Lysophosphatidylcholine
Authors: Li Keshuai , Egelandsdal Bjørg , Olsen Rolf E. 
Published: September 2018

AbstractSome lipid digestion pathways in fish deviate from those in mammals, and many differences may also be species dependent. This report describes a pathway for monoacylglycerol (MAG) and lysophospholipid absorption by intestinal enterocytes in brown trout that may be of significance in salmonids. When culturing primary cells in a medium containing 1‐ and 2‐MAG, we observed a massive hydrolysis of unesterified fatty acids. The hydrolysis activity was retained in the medium even after the removal of the cells. To further characterize these activities, both extracellular and isolated membrane proteins were tested for lipase activity toward triacylglycerol (TAG), diacylglycerol (DAG), MAG, phosphatidylcholine (PtdCho), and lysoPtdCho. In both cases, the main hydrolyzing activity was toward MAG followed by lysoPtdCho with very little activity toward DAG, TAG, or PtdCho. The extracellular and membrane proteins were partially purified by fast protein liquid chromatography and identified by proteomics (liquid chromatography–tandem mass spectrometry) focusing on lipase/hydrolase enzymes. In the membrane protein fraction, the data suggested that MAG was produced as an intermediate in the hydrolysis of lysoPtdCho by either lysophospholipase C or lysophospholipase D activity. Both abhydrolase‐domain‐containing protein 6 and abhydrolase‐domain‐containing protein 12 were identified in the membrane protein and they could be responsible for the hydrolysis of MAG. In the culture medium, low‐peptide matches were found for ABHD6 and phospholipases and further studies are needed. In summary, trout enterocytes are capable of hydrolyzing MAG and lysoPtdCho. The enzymes are both extracellular and membrane bound. The pathways may be of significance during lipid absorption in fish lacking a 1,3 specific pancreatic lipase.
Study of the Involvement of Phosphatidic Acid Formation in the Expression of Wound‐Responsive Genes in Cotton
Authors: Bourtsala Angeliki , Dafnis Ioannis , Chroni Angeliki , Farmaki Theodora , Galanopoulou Dia 
Published: September 2018

AbstractPlants use phospholipase D (PLD, EC 3.1.4.4)/phosphatidic acid (PtdOH) for the transduction of environmental signals including those coming from wounding. Based on our previous findings suggesting that wound‐induced PLDα‐derived PtdOH can act as a local signaling molecule in cotton (Gossypium hirsutum), we show that wounding immediately increases local NADPH oxidase (NADPHox) and cellulose synthase A (CeSA) gene expression. After developing a novel fluorimetric assay for the investigation of n‐butanol inhibitory effect on PLD activity, we show that only NADPHox gene upregulation is reduced when n‐butanol is applied prior to wounding. This suggests that NADPHox is a possible downstream target of PLD function, while a different CeSA‐involving response system may exist in cotton. Overall, this study provides new knowledge on signal‐transduction mechanisms following wounding of cotton leaves.
ScatterNet: A convolutional neural network for cone‐beam CT intensity correction
Authors: Hansen David C. , Landry Guillaume , Kamp Florian , Li Minglun , Belka Claus , Parodi Katia , Kurz Christopher 
Published: September 2018

PurposeTo demonstrate a proof‐of‐concept for fast cone‐beam CT (CBCT) intensity correction in projection space by the use of deep learning.MethodsThe CBCT scans and corresponding projections were acquired from 30 prostate cancer patients. Reference shading correction was performed using a validated method (CBCT), which estimates scatter and other low‐frequency deviations in the measured CBCT projections on the basis of a prior CT image obtained from warping the planning CT to the CBCT. A convolutional neural network (ScatterNet) was designed, consisting of an attenuation conversion stage followed by a shading correction stage using a UNet‐like architecture. The combined network was trained in 2D, utilizing pairs of measured and corrected projections of the reference method, in order to perform shading correction in projection space before reconstruction. The number of patients used for training, testing, and evaluation was 15, 7, and 8, respectively. The reconstructed CBCT was compared to CBCT in terms of mean and absolute errors (ME and MAE) for the eight evaluation patients (not included in the network training). Volumetric modulated arc photon therapy (VMAT) and intensity‐modulated proton therapy (IMPT) plans were generated on CBCT. Dose was recalculated on CBCT to evaluate its dosimetric accuracy. Single‐field uniform dose proton plans were utilized for proton range comparison of CBCT and CBCT.ResultsThe CBCT showed no cupping artifacts and a considerably smaller MAE and ME with respect to CBCT than the uncorrected CBCT (on average 144 Hounsfield units (HU) vs 46 HU for MAE and 138 HU vs −3 HU for ME). The pass‐rates using a 2% dose‐difference criterion at 50% dose cut‐off, were close to 100% for the VMAT plans of all patients when comparing CBCT to CBCT. For IMPT plans pass‐rates were clearly lower, ranging from 15% to 81%. Proton range differences of up to 5 mm occurred.ConclusionsUsing a deep convolutional neural network for CBCT intensity correction was shown to be feasible in the pelvic region for the first time. Dose calculation accuracy on CBCT was high for VMAT, but unsatisfactory for IMPT. With respect to the reference technique (CBCT), the neural network enabled a considerable increase in speed for intensity correction and might eventually allow for on‐the‐fly shading correction during CBCT acquisition.
Structural Basis for the Inhibition of Cyclin G‐Associated Kinase by Gefitinib
Authors: Ohbayashi Naomi , Murayama Kazutaka , Kato‐Murayama Miyuki , Kukimoto‐Niino Mutsuko , Uejima Tamami , Matsuda Takayoshi , Ohsawa Noboru , Yokoyama Shigeyuki , Nojima Hiroshi , Shirouzu Mikako 
Published: September 2018

AbstractGefitinib is the molecular target drug for advanced non‐small‐cell lung cancer. The primary target of gefitinib is the positive mutation of epidermal growth factor receptor, but it also inhibits cyclin G‐associated kinase (GAK). To reveal the molecular bases of GAK and gefitinib binding, structure analyses were conducted and determined two forms of the gefitinib‐bound nanobody⋅GAK kinase domain complex structures. The first form, GAK_1, has one gefitinib at the ATP binding pocket, whereas the second form, GAK_2, binds one each in the ATP binding site and a novel binding site adjacent to the activation segment C‐terminal helix, a unique element of the Numb‐associated kinase family. In the novel binding site, gefitinib binds in the hydrophobic groove around the activation segment, disrupting the conserved hydrogen bonds for the catalytic activity. These structures suggest possibilities for the development of selective GAK inhibitors for viral infections, such as the hepatitis C virus.
Cis/trans isomerization of proline peptide bonds in the backbone of cyclic disulfide‐bridged peptides
Authors: Sui Qiang , Rabenstein Dallas L. 
Published: September 2018

AbstractPeptides are of interest as potential therapeutic agents, including cyclic disulfide‐bridged peptides because of their limited conformational flexibility and enhanced stability toward proteolysis. To further constrain the flexibility of the peptide backbone, the disulfide‐bridged rings often contain a proline residue, which also serves to facilitate the formation of reverse‐turn structures. However, the proline residue increases the conformational diversity because the tertiary amide peptide bond to proline can exist as significant populations of both the cis and trans isomers. To identify features that affect the distribution between the cis and trans isomers of proline peptide bonds in disulfide‐bridged peptide rings, we have characterized by 1H NMR the kinetics and equilibria of the cis/trans isomerization of the proline peptide bonds for the linear dithiol and cyclic disulfide‐bridged forms of three families of proline‐containing peptides: Ac‐Cys‐Pro‐[NH(CH2)nCO]‐Cys‐NH2, where n = 1‐4; Ac‐Cys‐Xaa‐Pro‐Cys‐NH2 and Ac‐Cys‐Pro‐Xaa‐Cys‐NH2, where Xaa is Gly, Ala and Val; and Ac‐Cys‐Pro‐His‐(Ala)n‐Cys‐NH2, where n = 0‐5. The peptide Ac‐Cys‐Pro‐(4‐AMBA)‐Cys‐NH2, where 4‐AMBA is 4‐aminomethylbenzoic acid, was also studied to determine the effect of a rigid aromatic ring in the peptide backbone on the conformational properties of the Cys‐Pro peptide bond. Equilibrium constants were determined for cis/trans isomerization from the relative intensities of resonances for the cis and trans isomers, and rate constants for cis‐to‐trans and trans‐to‐cis isomerization were determined by the magnetization transfer NMR method. The cis/trans equilibrium is a dynamic equilibrium, and the equilibrium constants vary widely due to the wide range of kinetic stabilities of the various cis and trans isomers.
Laser/Electron Irradiation on Indium Phosphide (InP) Semiconductor: Promising Pathways to In Situ Formation of Indium Nanoparticles
Authors: Assis Marcelo , Macedo Nadia G. , Machado Thales R. , Ferrer Mateus M. , Gouveia Amanda F. , Cordoncillo Eloisa , Torres‐Mendieta Rafael , Beltrán‐Mir Hector , Mínguez‐Vega Gladys , Leite Edson R. , Sambrano Júlio R. , Andrés Juan , Longo Elson 
Published: September 2018

AbstractIn the current study, whether femtosecond laser and electron beam irradiation of indium phosphide (InP) are “green,” fast, and effective methods to produce metallic In nanoparticles is probed. High‐resolution transmission electron microscopy and energy‐dispersive X‐ray spectroscopy are employed to investigate the formation and growth of In nanoparticles on InP. Density functional theory and quantum theory of atoms in molecules calculations are employed to reveal the nature of formation of In nanoparticles under electron beam irradiation. These results expand the fundamental understanding of the atomic processes underpinning the mechanism of In−P bond rupture during the transformation process induced by the electron irradiation of the InP crystal by increasing the total number of electrons in the bulk structure.
A threonine zipper that mediates protein–protein interactions: Structure and prediction
Authors: Oi Curran , Treado John D. , Levine Zachary A. , Lim Christopher S. , Knecht Kirsten M. , Xiong Yong , O'Hern Corey S. , Regan Lynne 
Published: September 2018

AbstractWe present the structure of an engineered protein–protein interface between two beta barrel proteins, which is mediated by interactions between threonine (Thr) residues. This Thr zipper structure suggests that the protein interface is stabilized by close‐packing of the Thr residues, with only one intermonomer hydrogen bond (H‐bond) between two of the Thr residues. This Thr‐rich interface provides a unique opportunity to study the behavior of Thr in the context of many other Thr residues. In previous work, we have shown that the side chain (χ1) dihedral angles of interface and core Thr residues can be predicted with high accuracy using a hard sphere plus stereochemical constraint (HS) model. Here, we demonstrate that in the Thr‐rich local environment of the Thr zipper structure, we are able to predict the χ1 dihedral angles of most of the Thr residues. Some, however, are not well predicted by the HS model. We therefore employed explicitly solvated molecular dynamics (MD) simulations to further investigate the side chain conformations of these residues. The MD simulations illustrate the role that transient H‐bonding to water, in combination with steric constraints, plays in determining the behavior of these Thr side chains.Broader Audience Statement: Protein–protein interactions are critical to life and the search for ways to disrupt adverse protein–protein interactions involved in disease is an ongoing area of drug discovery. We must better understand protein–protein interfaces, both to be able to disrupt existing ones and to engineer new ones for a variety of biotechnological applications. We have discovered and characterized an artificial Thr‐rich protein–protein interface. This novel interface demonstrates a heretofore unknown property of Thr‐rich surfaces: mediating protein–protein interactions.
Anti-Inflammatory and Anti-Fibrotic Effects of Human Amniotic Membrane Mesenchymal Stem Cells and Their Potential in Corneal Repair
Authors: Navas Alejandro , Magaña-Guerrero Fátima Sofía , Domínguez-López Alfredo , Chávez-García César , Partido Graciela , Graue-Hernández Enrique O. , Sánchez-García Francisco Javier , Garfias Yonathan 
Published: September 2018

Abstract
Acute ocular chemical burns are ophthalmic emergencies requiring immediate diagnosis and treatment as they may lead to permanent impairment of vision. The clinical manifestations of such burns are produced by exacerbated innate immune response via the infiltration of inflammatory cells and activation of stromal fibroblasts. New therapies are emerging that are dedicated to repair mechanisms that improve the ocular surface after damage; for example, transplantation of stem cells (SC) has been successfully reported for this purpose. The pursuit of easily accessible, noninvasive procedures to obtain SC has led researchers to focus on human tissues such as amniotic membrane. Human amniotic mesenchymal SC (hAM-MSC) inhibits proinflammatory and fibrotic processes in different diseases. hAM-MSC expresses low levels of classical MHC-I and they do not express MHC-II, making them suitable for regenerative medicine. The aim of this study was to evaluate the effect of intracameral injection of hAM-MSC on the clinical manifestations, the infiltration of inflammatory cells, and the activation of stromal fibroblasts in a corneal alkali-burn model. We also determined the in vitro effect of hAM-MSC conditioned medium (CM) on α-SMA+ human limbal myofibroblast (HLM) frequency and on release of neutrophil extracellular traps (NETs). Our results show that intracameral hAM-MSC injection reduces neovascularization, opacity, stromal inflammatory cell infiltrate, and stromal α-SMA+ cells in our model. Moreover, in in vitro assays, CM from hAM-MSC decreased the quantity of α-SMA+ HLM and the release of NETs. These results suggest that intracameral hAM-MSC injection induces an anti-inflammatory and anti-fibrotic environment that promotes corneal wound healing.
Boosting Electrochemical Hydrogen Evolution of Porous Metal Phosphides Nanosheets by Coating Defective TiO2 Overlayers
Authors: Liu Xiufang , Hu Qi , Zhu Bin , Li Guomin , Fan Liangdong , Chai Xiaoyan , Zhang Qianling , Liu Jianhong , He Chuanxin 
Published: September 2018

AbstractNonprecious transition metal phosphides (TMPs) have emerged as robust electrocalysts for the hydrogen evolution reaction (HER). However, the TMPs suffer from low activity for water dissociation, which greatly limits the efficiency for alkaline HER. Here, a facile yet robust strategy is reported to boost the HER of metal phosphides by coating defective TiO2 overlayers. The oxygen vacancies (Ov) on defective TiO2 overlayers are found to possess high activity for adsorption and dissociation of water, thereby significantly promoting the initial Volmer step of HER to generate the reactive hydrogen atoms. Moreover, the porous (Co, Ni)2P (i.e., Co2P and Ni2P) nanosheets provide enough active sites for adsorption and recombination of reactive hydrogen atoms to produce hydrogen gas. The catalytic synergy of (Co, Ni)2P and Ov coupled with the hierarchically porous structure renders the porous (Co, Ni)2P@0.1TiO2 nanosheet arrays excellent electrocatalysts for HER, showing a small overpotential (92 mV) to yield a current density of 10 mA cm−2, a small Tafel slope (49 mV dec−1), and an outstanding stability. This work demonstrates a surface decoration route for enhancing the activity of nonprecious metal‐based electrocatalysts for HER.
Preparation of an organic monolithic column based on carboxyethyl acrylate for capillary liquid chromatography
Authors: Gama Mariana R. , Lee Milton L. , Bottoli Carla B. G. 
Published: September 2018

AbstractIn the current study, a monolithic capillary column based on carboxyethyl acrylate and polyethylene glycol dimethacrylate was successfully prepared by photo‐initiated polymerization in the presence of selected porogens. The columns were used in capillary liquid chromatographic separations in the hydrophilic interaction mode. The monolith composition was optimized by changing the type and amount of the polar monomers. Characterization by scanning electronic microscopy indicated the monolithic columns possessed a homogeneous column bed. After the optimization, the synthesized monolith showed good selectivity for the separation of acrylamides in the hydrophilic interaction mode, with chromatographic efficiency of about 45000 plates m−1 for the most retained compound.
Using Literacy Approaches to Begin the Conversation on Racial Illiteracy
Authors: Kaczmarczyk Annemarie , Allee‐Herndon Karyn A. , Roberts Sherron Killingsworth 
Published: September 2018

AbstractSystemic racism, and the white privilege that it supports and maintains, remains firmly entrenched in U.S. culture. The current educational climate may be experiencing an increase in racial animus, and students are not immune to the challenges they face as a result. For teachers who truly believe that all children can learn and are entitled to the very best opportunities to reach their full potential, racism must be considered a barrier to reaching this goal for students of color. To actively create an anti‐racist climate in classrooms, educators must actively engage in racial literacy efforts with students. High‐quality, age‐appropriate books with social justice themes can help facilitate conversations about racism and privilege. Integrating literacy approaches, such as literature circles, dialogue journals, and writing impactful pieces, can start important conversations to eradicate racial illiteracy in our classrooms and to better our world.
Screening for morbidly adherent placenta in early pregnancy
Authors: Panaiotova J. , Tokunaka M. , Krajewska K. , Zosmer N. , Nicolaides K. H. 
Published: September 2018

ABSTRACTObjectiveTo estimate the diagnostic accuracy of a two‐stage strategy for early prediction of morbidly adherent placenta (MAP). In the first stage, at 11–13 weeks' gestation, women with low‐lying placenta and history of uterine surgery are classified as being at high risk for MAP and, in the second stage, at 12–16 weeks, these high‐risk pregnancies are assessed at a specialist MAP clinic.MethodsThis was a prospective study in women having an ultrasound scan at 11–13 weeks' gestation as a part of routine pregnancy care. Women with low‐lying placenta and a history of uterine surgery were followed up at a specialist MAP clinic at 12–16 weeks' gestation, 20–24 weeks and 28–34 weeks. At each visit to the MAP clinic, an ultrasound scan was carried out and the following features suggestive of MAP were recorded: non‐visible Cesarean section scar; bladder wall interruption; thin retroplacental myometrium; presence of intraplacental lacunar spaces; presence of retroplacental arterial‐trophoblastic blood flow; and irregular placental vascularization demonstrated by three‐dimensional power Doppler.ResultsScreening at 11–13 weeks was carried out in 22 604 singleton pregnancies, 1298 (6%) of which were considered to be at high risk of MAP because they had previous uterine surgery and low‐lying placenta. At the MAP clinic at 12–16 weeks, the diagnosis of MAP was suspected in 14 cases and this was confirmed at delivery in 13. In the rest of the population, there were no cases of MAP.ConclusionAccurate prediction of MAP can be achieved by ultrasound examination at 12–16 weeks' gestation. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.