bluuebunny/crossref_metadata_2025_split huggingface dataset:
Human and Not-so-Human Footprint Images on the Rocks
Authors: Tanner William F. 
Published: July 2018

Human footprints, and similar images, have been described from rocks on various continents: North and South America, Europe, Asia and Africa; on rocks of any age, including Precambrian metamorphics.Many of these images are carved. The Precambrian “footprints” of North Georgia were carved on the modern rock surface, but are not within the rock. Weathering rates are so high that they can be only some hundreds of years old. The instep and all of the toes were sharply defined, as is characteristic of carvings. The number of toes was not constant from print to print. The Cretaceous “footprints” of Missouri were also sharply-defined carvings, although they appeared on the bedding plane. There are no “jumping” indentations at either heel or toe, even though the two prints (side by side) were completely isolated on a wide smooth surface. The Precambrian “footprints” of Sweden likewise are carvings, on the modern weathering surface, with sharply-detailed outlines.Many more of these images are not footprints of any animal at all. They vary in size, shape, and depth of indentation. Just as carved images typically show too much sharp detail, these images do not show any detail, rarely resemble the correct shape, and commonly are not consistent in size. The Cretaceous “footprints” of central Texas are a hodge-podge of random markings of various kinds, the large majority of which were formed by differential erosion of a non-homogenous limestone. Whereas dinosaur footprints in the same rocks show systematic patterns and sequences, the so-called “human footprints” are erratic natural markings and excavations.A tiny minority of these images was made by the feet of human or primitive humanoid creatures. These genuine footprints show recognizable patterns and sequences, but not much detail; occur on bedding planes; and date only from Pleistocene or late Pliocene rocks.
The Campotosto Seismic Gap in Between the 2009 and 2016–2017 Seismic Sequences of Central Italy and the Role of Inherited Lithospheric Faults in Regional Seismotectonic Settings
Authors: Falcucci E. , Gori S. , Bignami C. , Pietrantonio G. , Melini D. , Moro M. , Saroli M. , Galadini F. 
Published: July 2018

AbstractThe 2016–2017 seismic sequence, in central Italy, was caused by the Mt. Vettore‐Mt. Bove active fault system, which generated three mainshocks, the largest one of Mw6.6, on 30 October 2016. On 18 January 2017, four Mw5–5.5 seismic events nucleated on the Campotosto active fault. The fault is considered as potentially responsible forM~6.6 seismic events and a seismic gap. The structure also nucleated a Mw5.4 aftershock during the 2009 L'Aquila seismic sequence. We here combined new geological/geomorphological field data, 1945 aerial photographs interpretation, geodetic (Differential Interferometric Synthetic Aperture Radar and Global Positioning System) data, and local historical seismicity analysis to determine how much of the Campotosto seismogenic source ruptured during the 2009 and 2016–2017 seismic sequences. The obtained residual seismic moment of the Campotosto seismic gap is in the range Mw6.4–6.6 earthquake. Moreover, the review of the regional tectonic setting and evolution allowed us a brand new and comprehensive reading of the seismotectonics for the region, in terms of both seismic potential and segmentation of the seismogenic sources, which results strictly connected to the long‐term activity of inherited lithospheric discontinuities, among which the major Ancona‐Anzio fault. We here first highlight that such regional structures strongly influenced the structural setting and evolution of the surrounding regions, in a progressive and continuous process of tectonic inversions, which implies that structural heritage must be understood and considered when dealing with seismotectonics of a given tectonically active region.
Rotations of Normal Fault Blocks Quantify Extension in the Central Tauride Intramontane Basins, SW Turkey
Authors: Koç Ayten , van Hinsbergen Douwe J. J. , Langereis Cor G. 
Published: July 2018

AbstractQuantifying the amount of stretching in extensional basin systems is often challenging in the absence of seismic profiles or boreholes. However, when fault spacing and orientation as well as vertical axis rotation patterns are known, map‐view restoration may provide a good estimate of total extension. This integrated structural and paleomagnetic approach provides a relatively straightforward tool in extensional basin restoration and fault zone kinematic analysis. Here we provide results of an extensive paleomagnetic survey of the Neogene Central Tauride intramontane basins (SW Turkey), where previous work revealed a complex array of basin‐bounding normal faults and relay ramps. In total, 437 oriented cores were sampled at 43 sites distributed within Miocene‐Pliocene continental sedimentary rocks from the Ilgın, Altınapa, Yalvaç, and Beyşehir basins. Despite the more or less coherent overall strike of the mountain belt and basins, rotations vary from ~42° clockwise (Yalvaç) to ~10° (Beyşehir), ~21° (Ilgın), and ~30° (Altınapa) counterclockwise. We show that the rotation pattern is related to normal faults and lateral variations in fault displacement superimposed on regional rotation patterns. We restore these to estimate a minimum NE‐SW horizontal extension of ~30–35 km across the basin system. As a consequence of our reconstruction, it appears that the Sultandağları range that exposes low‐grade metamorphic Paleozoic and Mesozoic rocks of the Geyikdağı and Bolkardağ nappes of the Taurides represents a Miocene extensional core complex.
Assessment of genetic factor and depression interactions for asthma symptom severity in cohorts of childhood and elderly asthmatics
Authors: Park Heung-Woo , Song Woo-Jung , Cho Sang-Heon , McGeachie Michael J. , Martinez Fernando , Mauger Dave , Bender Bruce G. , Tantisira Kelan G. 
Published: July 2018

AbstractIt is well known that depression is associated with asthma symptoms. We assessed the combined effects of genetic factors and depression on asthma symptom severity using Bayesian network (BN) analysis. The common 100 top-ranked single-nucleotide polymorphisms (SNPs) were obtained from two genome-wide association studies of symptom severity in two childhood asthmatics trials (CAMP (Childhood Asthma Management Program) and CARE (Childhood Asthma Research and Education)). Using SNPs plus five discretized variables (depression, anxiety, age, sex, and race), we performed BN analysis in 529 CAMP subjects. We identified two nodes (depression and rs4672619 mapping to ERBB4 (Erb-B2 receptor tyrosine kinase 4)) that were within the Markov neighborhood of the symptom node in the network and then evaluated the interactive effects of depressive status and rs4672619 genotypes on asthma symptom severity. In childhood asthmatics with homozygous reference alleles, severe depression was related to less severe symptoms. However, in childhood asthmatics with heterozygous alleles and homozygous variant alleles, depression and symptom severity showed a positive correlation (interaction permutation P value = 0.019). We then tried to evaluate whether the interactive effects that we found were sustained in another independent cohort of elderly asthmatics. Contrary to the findings from childhood asthmatics, elderly asthmatics with homozygous reference alleles showed a positive correlation between depression and symptom severity, and elderly asthmatics with heterozygous alleles and homozygous variant alleles showed a negative correlation (interaction permutation P value = 0.003). In conclusion, we have identified a novel SNP, rs4672619, that shows interactive effects with depression on asthma symptom severity in childhood and elderly asthmatics in opposite directions.
Fine-grained optimization method for crystal structure prediction
Authors: Terayama Kei , Yamashita Tomoki , Oguchi Tamio , Tsuda Koji 
Published: July 2018

AbstractCrystal structure prediction based on first-principles calculations is often achieved by applying relaxation to randomly generated initial structures. Relaxing a structure requires multiple optimization steps. It is time consuming to fully relax all the initial structures, but it is difficult to figure out which initial structure leads to the optimal solution in advance. In this paper, we propose a optimization method for crystal structure prediction, called Look Ahead based on Quadratic Approximation, that optimally assigns optimization steps to each candidate structure. It allows us to identify the most stable structure with a minimum number of total local optimization steps. Our simulations using known systems Si, NaCl, Y2Co17, Al2O3, and GaAs showed that the computational cost can be reduced significantly compared to random search. This method can be applied for controlling all kinds of local optimizations based on first-principles calculations to obtain best results under restricted computational resources.
Rapid Screening of Ellagitannins in Natural Sources via Targeted Reporter Ion Triggered Tandem Mass Spectrometry
Authors: Bowers Jeremiah J. , Gunawardena Harsha P. , Cornu Anaëlle , Narvekar Ashwini S. , Richieu Antoine , Deffieux Denis , Quideau Stéphane , Tharayil Nishanth 
Published: July 2018

AbstractComplex biomolecules present in their natural sources have been difficult to analyze using traditional analytical approaches. Ultrahigh-performance liquid chromatography (UHPLC-MS/MS) methods have the potential to enhance the discovery of a less well characterized and challenging class of biomolecules in plants, the ellagitannins. We present an approach that allows for the screening of ellagitannins by employing higher energy collision dissociation (HCD) to generate reporter ions for classification and collision-induced dissociation (CID) to generate unique fragmentation spectra for isomeric variants of previously unreported species. Ellagitannin anions efficiently form three characteristic reporter ions after HCD fragmentation that allows for the classification of unknown precursors that we call targeted reporter ion triggering (TRT). We demonstrate how a tandem HCD-CID experiment might be used to screen natural sources using UHPLC-MS/MS by application of 22 method conditions from which an optimized data-dependent acquisition (DDA) emerged. The method was verified not to yield false-positive results in complex plant matrices. We were able to identify 154 non-isomeric ellagitannins from strawberry leaves, which is 17 times higher than previously reported in the same matrix. The systematic inclusion of CID spectra for isomers of each species classified as an ellagitannin has never been possible before the development of this approach.
Bioelectric-calcineurin signaling module regulates allometric growth and size of the zebrafish fin
Authors: Daane Jacob M. , Lanni Jennifer , Rothenberg Ina , Seebohm Guiscard , Higdon Charles W. , Johnson Stephen L. , Harris Matthew P. 
Published: July 2018

AbstractThe establishment of relative size of organs and structures is paramount for attaining final form and function of an organism. Importantly, variation in the proportions of structures frequently underlies adaptive change in morphology in evolution and maybe a common mechanism underlying selection. However, the mechanism by which growth is integrated within tissues during development to achieve proper proportionality is poorly understood. We have shown that signaling by potassium channels mediates coordinated size regulation in zebrafish fins. Recently, calcineurin inhibitors were shown to elicit changes in zebrafish fin allometry as well. Here, we identify the potassium channelkcnk5bas a key player in integrating calcineurin’s growth effects, in part through regulation of the cytoplasmic C-terminus of the channel. We propose that the interaction between Kcnk5b and calcineurin acts as a signaling node to regulate allometric growth. Importantly, we find that this regulation is epistatic to inherent mechanisms instructing overall size as inhibition of calcineurin is able to bypass genetic instruction of size as seen insofand wild-type fins, however, it is not sufficient to re-specify positional memory of size of the fin. These findings integrate classic signaling mediators such as calcineurin with ion channel function in the regulation of size and proportion during growth.
Benzo(a)pyrene in Cigarette Smoke Enhances HIV-1 Replication through NF-κB Activation via CYP-Mediated Oxidative Stress Pathway
Authors: Ranjit Sabina , Sinha Namita , Kodidela Sunitha , Kumar Santosh 
Published: July 2018

AbstractSmoking aggravates HIV-1 pathogenesis and leads to decreased responses to antiretroviral therapy. In this study, we aim to find a molecular mechanism that would explain smoking-induced HIV-1 replication. Benzo(a)pyrene (BaP), a major carcinogen in cigarette, requires metabolic activation through cytochrome P450s (CYPs) to exert its toxic effects. We hypothesized that CYP-mediated BaP metabolism generates reactive oxygen species (ROS), and the resultant oxidative stress aggravates HIV-1 replication. As expected, we observed ~3 to 4-fold increase in HIV-1 replication in U1 cells and human primary macrophages after chronic BaP exposure. We also observed ~30-fold increase in the expression of CYP1A1 at mRNA level, ~2.5-fold increase in its enzymatic activity as well as elevated ROS and cytotoxicity in U1 cells. The knock-down of the CYP1A1 gene using siRNA and treatment with selective CYP inhibitors and antioxidants significantly reduced HIV-1 replication. Further, we observed a nuclear translocation of NF-κB subunits (p50 and p65) after chronic BaP exposure, which was reduced by treatment with siRNA and antioxidants/CYP inhibitors. Suppression of NF-κB pathway using specific NF-κB inhibitors also significantly reduced HIV-1 replication. Altogether, our results suggest that BaP enhances HIV-1 replication in macrophages by a CYP-mediated oxidative stress pathway followed by the NF-κB pathway.
Interaction of LEF1 with TAZ is necessary for the osteoblastogenic activity of Wnt3a
Authors: Kida Jumpei , Hata Kenji , Nakamura Eriko , Yagi Hiroko , Takahata Yoshifumi , Murakami Tomohiko , Maeda Yoshinobu , Nishimura Riko 
Published: July 2018

AbstractCanonical Wnt signalling plays an important role in osteoblast differentiation and bone formation. However, the molecular mechanisms by which canonical Wnt signalling exerts its osteoblastogenic effect remain elusive. Here, we investigated the relationship between lymphoid enhancer-binding factor 1 (LEF1) and transcriptional co-activator with PDZ-binding motif (TAZ), both of which are transcriptional regulators that mediate canonical Wnt signalling during osteoblast differentiation. Reporter assay and co-immunoprecipitation experiments revealed functional and physical interaction between LEF1 and TAZ. Overexpression of dominant-negative forms of either LEF1 or TAZ markedly inhibited Wnt3a-dependent osteoblast differentiation. Moreover, we found that LEF1 and TAZ formed a transcriptional complex with runt-related transcription factor 2 (Runx2) and that inhibition of LEF1 or TAZ by their dominant-negative forms dramatically suppressed the osteoblastogenic activity of Ruxn2. Additionally, Wnt3a enhanced osteoblast differentiation induced by bone morphogenetic protein 2 (BMP2), which stimulates osteoblast differentiation by regulating Runx2. Collectively, these findings suggest that interaction between LEF1 and TAZ is crucial for the osteoblastogenic activity of Wnt3a and that LEF1 and TAZ contribute to the cooperative effect of Wnt3a and BMP2 on osteoblast differentiation through association with Runx2.
Central insulin action induces activation of paraventricular oxytocin neurons to release oxytocin into circulation
Authors: Zhang Boyang , Nakata Masanori , Nakae Jun , Ogawa Wataru , Yada Toshihiko 
Published: July 2018

AbstractOxytocin neurons in the paraventricular nucleus (PVN) of hypothalamus regulate energy metabolism and reproduction. Plasma oxytocin concentration is reduced in obese subjects with insulin resistance. These findings prompted us to hypothesize that insulin serves to promote oxytocin release. This study examined whether insulin activates oxytocin neurons in the PVN, and explored the underlying signaling. We generated the mice deficient of 3-phosphoinositide-dependent protein kinase-1 (PDK1), a major signaling molecule particularly for insulin, specifically in oxytocin neurons (Oxy Pdk1 KO). Insulin increased cytosolic calcium concentration ([Ca2+]i) in oxytocin neurons with larger (≧25 μm) and smaller (<25 μm) diameters isolated from PVN in C57BL/6 mice. In PDK1 Oxy Pdk1 KO mice, in contrast, this effect of insulin to increase [Ca2+]i was markedly diminished in the larger-sized oxytocin neurons, while it was intact in the smaller-sized oxytocin neurons. Furthermore, intracerebroventricular insulin administration induced oxytocin release into plasma in Oxy Cre but not Oxy Pdk1 KO mice. These results demonstrate that insulin PDK1-dependently preferentially activates PVN magnocellular oxytocin neurons to release oxytocin into circulation, possibly serving as a mechanism for the interaction between metabolism and perinatal functions.
Spontaneous light-mediated magnetism in cold atoms
Authors: Krešić I. , Labeyrie G. , Robb G. R. M. , Oppo G.-L. , Gomes P. M. , Griffin P. , Kaiser R. , Ackemann T. 
Published: July 2018

AbstractCold atom setups are now commonly employed in simulations of condensed matter phenomena. We present an approach to induce strong magnetic interactions between atoms on a self-organized lattice using diffraction of light. Diffractive propagation of structured light fields leads to an exchange between phase and amplitude modulated planes which can be used to couple atomic degrees of freedom via optical pumping nonlinearities. In the experiment a cold cloud of Rb atoms placed near a retro-reflecting mirror is driven by a detuned pump laser. We demonstrate spontaneous magnetic ordering in the Zeeman sublevels of the atomic ground state: anti-ferromagnetic structures on a square lattice and ferrimagnetic structures on a hexagonal lattice in zero and a weak longitudinal magnetic field, respectively. The ordered state is destroyed by a transverse magnetic field via coherent dynamics. A connection to the transverse (quantum) Ising model is drawn.
Temporal evolution of arch filaments as seen in He I 10 830 Å
Authors: González Manrique S. J. , Kuckein C. , Collados M. , Denker C. , Solanki S. K. , Gömöry P. , Verma M. , Balthasar H. , Lagg A. , Diercke A. 
Published: July 2018

Aims. We study the evolution of an arch filament system (AFS) and of its individual arch filaments to learn about the processes occurring in them.
Methods. We observed the AFS at the GREGOR solar telescope on Tenerife at high cadence with the very fast spectroscopic mode of the GREGOR Infrared Spectrograph (GRIS) in the He I 10 830 Å spectral range. The He I triplet profiles were fitted with analytic functions to infer line-of-sight (LOS) velocities to follow plasma motions within the AFS.
Results. We tracked the temporal evolution of an individual arch filament over its entire lifetime, as seen in the He I 10 830 Å triplet. The arch filament expanded in height and extended in length from 13″ to 21″. The lifetime of this arch filament is about 30 min. About 11 min after the arch filament is seen in He I, the loop top starts to rise with an average Doppler velocity of 6 km s−1. Only two minutes later, plasma drains down with supersonic velocities towards the footpoints reaching a peak velocity of up to 40 km s−1 in the chromosphere. The temporal evolution of He I 10 830 Å profiles near the leading pore showed almost ubiquitous dual red components of the He I triplet, indicating strong downflows, along with material nearly at rest within the same resolution element during the whole observing time.
Conclusions. We followed the arch filament as it carried plasma during its rise from the photosphere to the corona. The material then drained toward the photosphere, reaching supersonic velocities, along the legs of the arch filament. Our observational results support theoretical AFS models and aids in improving future models.
Upper atmospheres of terrestrial planets: Carbon dioxide cooling and the Earth’s thermospheric evolution
Authors: Johnstone C. P. , Güdel M. , Lammer H. , Kislyakova K. G. 
Published: July 2018

Context.The thermal and chemical structures of the upper atmospheres of planets crucially influence losses to space and must be understood to constrain the effects of losses on atmospheric evolution.Aims.We develop a 1D first-principles hydrodynamic atmosphere model that calculates atmospheric thermal and chemical structures for arbitrary planetary parameters, chemical compositions, and stellar inputs. We apply the model to study the reaction of the Earth’s upper atmosphere to large changes in the CO2abundance and to changes in the input solar XUV field due to the Sun’s activity evolution from 3 Gyr in the past to 2.5 Gyr in the future.Methods.For the thermal atmosphere structure, we considered heating from the absorption of stellar X-ray, UV, and IR radiation, heating from exothermic chemical reactions, electron heating from collisions with non-thermal photoelectrons, Joule heating, cooling from IR emission by several species, thermal conduction, and energy exchanges between the neutral, ion, and electron gases. For the chemical structure, we considered ~500 chemical reactions, including 56 photoreactions, eddy and molecular diffusion, and advection. In addition, we calculated the atmospheric structure by solving the hydrodynamic equations. To solve the equations in our model, we developed the Kompot code and have provided detailed descriptions of the numerical methods used in the appendices.Results.We verify our model by calculating the structures of the upper atmospheres of the modern Earth and Venus. By varying the CO2abundances at the lower boundary (65 km) of our Earth model, we show that the atmospheric thermal structure is significantly altered. Increasing the CO2abundances leads to massive reduction in thermospheric temperature, contraction of the atmosphere, and reductions in the ion densities indicating that CO2can significantly influence atmospheric erosion. Our models for the evolution of the Earth’s upper atmosphere indicate that the thermospheric structure has not changed significantly in the last 2 Gyr and is unlikely to change signficantly in the next few Gyr. The largest changes that we see take place between 3 and 2 Gyr ago, with even larger changes expected at even earlier times.