bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rapid Late Eocene Exhumation of the Sivas Basin (Central Anatolia) Driven by Initial Arabia‐Eurasia Collision
Authors: Darin M. H. , Umhoefer P. J. , Thomson S. N. 
Published: September 2018

AbstractContinental collisions exert a profound influence on the configuration and evolution of orogenic systems. The effects of Arabia‐Eurasia collision on the geodynamics of the eastern Mediterranean are difficult to unravel, however, because the timing of initial collision (i.e., intercontinental contact) remains controversial. We present the first detrital and bedrock apatite fission track and (U‐Th‐Sm)/He thermochronology, and detrital zircon U‐Pb constraints from the Sivas Basin and eastern Taurides in central Anatolia (Turkey), which provide a detailed record of Cenozoic orogenesis in the hinterland of the Arabia‐Eurasia collision zone. Our results indicate rapid middle Eocene burial followed by shortening, rapid cooling (up to ~25–45 °C/myr), and initiation of the southern Sivas fold‐thrust belt (SSFTB) during the late Eocene (~40–34 Ma), consistent with evidence of a coeval basin‐wide unconformity. We interpret that rapid late Eocene cooling of the SSFTB reflects exhumation driven by the northward propagation of retroforeland contraction into the Sivas Basin from the middle to late Eocene, and we propose that these events were due to initial soft collision of the thinned Arabian passive margin by ~45 Ma. This timing of the inception of collision is supported by a regional compilation of apatite fission track data that indicates rapid cooling and hinterland exhumation throughout central and eastern Anatolia from ~45 to 20 Ma, which was synchronous with a widespread magmatic lull from ~40 to 20 Ma. The data presented here are compatible with a widely accepted transition to more mature or hard collision at ~20 Ma, probably related to the arrival of thick Arabian crust along the Bitlis suture zone.
Field‐Aligned Potentials at Mars From MAVEN Observations
Authors: Xu Shaosui , Mitchell David L. , McFadden James P. , Collinson Glyn , Harada Yuki , Lillis Robert , Mazelle Christian , Connerney J. E. P. 
Published: September 2018

AbstractOne possible ion escape channel at Mars is a polar wind‐like outflow driven by parallel electric fields and/or other acceleration mechanisms. With independent potential estimates from ionospheric photoelectron measurements by the Solar Wind Electron Analyzer (SWEA) and ion measurements by the SupraThermal And Thermal Ion Composition (STATIC) onboard the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft, magnetic field‐aligned potentials are calculated as the difference of the two. The calculated field‐aligned potentials have average values that range from 0 to −1.5 V, relative to the ionospheric source region. These field‐aligned potentials likely result from ambipolar electric fields and are found on both closed and open field lines. On the dayside, these potentials range from 0 to −0.7 V, corresponding to an electric field magnitude <3 mV/km, which peaks near the ion exobase and can effectively accelerate ions and enhance ion outflow.
MGS‐TES Spectra Suggest a Basaltic Component in the Regolith of Phobos
Authors: Glotch Timothy D. , Edwards Christopher S. , Yesiltas Mehmet , Shirley Katherine A. , McDougall Dylan S. , Kling Alexander M. , Bandfield Joshua L. , Herd Christopher D. K. 
Published: September 2018

AbstractThe origins of the Martian moons Phobos and Deimos have been the subjects of considerable debate. Visible and near‐infrared spectra of these bodies are dark and nearly featureless, with red slopes of varying degrees. These spectra are generally consistent with those of carbonaceous asteroids, leading to the hypothesis that Phobos and Deimos are captured carbonaceous asteroids. The shapes and inclinations of the orbits of Phobos and Deimos present problems for the asteroid capture hypothesis. This had led researchers to suggest that Phobos and Deimos coaccreted with Mars or that they are the result of an impact with Mars or in the Mars vicinity. In this work, we reexamine Mars Global Surveyor Thermal Emission Spectrometer (MGS‐TES) data of Phobos and compare spectra of the Phobos surface to mid‐IR spectra of the ungrouped C2 meteorite Tagish Lake (a suggested analog for D‐class asteroids) and particulate basalt and phyllosilicate samples (mixed with carbon black to reduce their visible albedos) acquired in a simulated airless body environment. We find that Tagish Lake is a poor mid‐IR spectral analog to Phobos and that major spectral features in the Phobos spectrum are best matched by a silicate transparency feature similar to that found for finely particulate basalt. Other features in the spectrum are likely best explained by a phyllosilicate component. We suggest that these results indicate that at a portion of the Phobos surface regolith is derived from the Martian crust.
Large Uptake of Atmospheric OCS Observed at a Moist Old Growth Forest: Controls and Implications for Carbon Cycle Applications
Authors: Rastogi Bharat , Berkelhammer Max , Wharton Sonia , Whelan Mary E. , Itter Malcolm S. , Leen J. Brian , Gupta Manish X. , Noone David , Still Christopher J. 
Published: September 2018

AbstractDiurnal and vertical patterns of carbonyl sulfide (OCS) and CO2 mixing ratios above and within a 60‐m‐tall old‐growth temperate forest are presented. Canopy air from four different heights was sampled in situ using a continuous integrated cavity output spectroscopy analyzer during August–September 2014. Measurements revealed large vertical gradients in OCS, from which we inferred ecosystem fluxes. The diurnal cycle of OCS mixing ratios at all heights exhibited a typical pattern characterized by nighttime drawdown, an early morning minimum, and a maximum of OCS around midday. Daytime increase in the upper canopy is attributed to entrainment of planetary boundary layer air into the canopy. The ecosystem was found to be a large daytime sink of OCS (mean maximum daytime flux ~ −75 pmol · m−2 · s−1). Mean leaf relative uptake (concentration normalized uptake of OCS flux to CO2 uptake) was found to be 6.9. We discuss this high leaf relative uptake in the context of the presence and distribution of epiphytes at the site. While epiphytic uptake of OCS has been studied before, we show for the first time that this may contribute significantly to ecosystem fluxes under humid or moist conditions. We test this theory using a chamber experiment measuring epiphytic fluxes for two species of lichen and one moss species (in situ and in a laboratory). We suggest that the role of epiphytes should be explicitly considered when using OCS as a tracer of ecosystem‐scale photosynthesis in forest ecosystems with abundant epiphytic cover and biomass.
Five‐Year Results From the Engineering Radiation Monitor and Solar Cell Monitor on the VanAllen Probes Mission
Authors: Maurer R. H. , Goldsten J. O. , Butler M. H. , Fretz K. 
Published: September 2018

AbstractThe Engineering Radiation Monitor measures dose, dose rate, and charging currents on the Van Allen Probes mission to study the dynamics of Earth's Van Allen radiation belts. Over 5 years, results from this monitor show a variation in dose rates with time, a correlation between the dosimeter and charging current data, and a comparison of cumulative dose to prelaunch modeling. Solar cell degradation monitor patches track the decrease in solar array output as displacement damage accumulates. The Solar Cell Monitor shows ~33% cumulative degradation in maximum power after 5.1 years of the mission. The desire to extend the mission to ~2,500 days from 800 days created increased requirements for the ionizing radiation hardness of spacecraft and science instrument electronics. We describe the investigations that insured compliance with these enhanced requirements.
Linc02527 promoted autophagy in Intrahepatic cholestasis of pregnancy
Authors: Hu Jianguo , Liu Li , Gong Yangyang , Zhang Lei , Gan Xiaoling , Luo Xiaodong , Yu Tinghe , Zhong Xiaocui , Deng Xinru , Hu Lina , Zhang Zhanyu , Dong Xiaojing 
Published: September 2018

AbstractLncRNA plays a crucial role in human disease. However, the expression and function of LncRNA in ICP(Intrahepatic cholestasis of pregnancy) is still not fully elucidated. In this study, we found Linc02527 was increased expression in placenta and serum of ICP patients. Ectopically expression of Linc02527 promoted autophagy and proliferate in HTR8 cells. Silencing Linc02527 suppressed the autophagy and proliferate in HTR8 cells. Mechanically study revealed that Linc02527 regulated the expression of ATG5 and ATG7 by sponging miR-3185. Linc02527 directly binding to YBX1 and activated P21. The growth of C57 mouse was retarded when autophagy was activated. In normal condition, inhibited autophagy using chloroquine did not affect the growth of C57 mouse. However, in the condition of autophagy was activated, inhibited autophagy using chloroquine can improve the growth of C57 mouse. Overall, the results of this study identified Linc02527 as a candidate biomarker in ICP and a potential target for ICP therapy. Chloroquine was a potential drug for ICP therapy.
Parkin-mediated mitophagy as a potential therapeutic target for intervertebral disc degeneration
Authors: Zhang Zengjie , Xu Tianzhen , Chen Jiaoxiang , Shao Zhenxuan , Wang Ke , Yan Yingchao , Wu Congcong , Lin Jialiang , Wang Haoli , Gao Weiyang , Zhang Xiaolei , Wang Xiangyang 
Published: September 2018

AbstractIntervertebral disc degeneration (IDD) is a complicated pathological condition blamed for low back pain. Mitochondrion is of vital importance for cellular homeostasis, and mitochondrial dysfunction is considered to be one of the major causes of cellular damage. Mitophagy is a cellular process to eliminate impaired mitochondria and showed protective effects in various diseases; however, its role in IDD is still not clear. Here, we explore the role of Parkin-mediated mitophagy in IDD. In this study, we found that Parkin was upregulated in degenerative nucleus pulposus (NP) tissues in vivo as well as in TNF-α stimulated NP cells in vitro. Knockdown of Parkin by siRNA showed that Parkin is crucial for apoptosis and mitochondrion homeostasis in NP cells. Further study showed that upregulation of Parkin by salidroside may eliminate impaired mitochondria and promote the survival of NP cells through activation of mitophagy in vitro. In in vivo study, we found that salidroside could inhibit the apoptosis of NP cells and ameliorate the progression of IDD. These results suggested that Parkin is involved in the pathogenesis of IDD and may be a potential therapeutic target for IDD.
Kinetics of thermally activated triplet fusion as a function of polymer chain packing in boosting the efficiency of organic light emitting diodes
Authors: Dey Amrita , Chandrasekaran Naresh , Chakraborty Dwaipayan , Johari Priya , McNeill Christopher R. , Rao Akshay , Kabra Dinesh 
Published: September 2018

AbstractUnderstanding the photophysical process governing the operation of the organic light emitting diodes (OLEDs) and how they are affected by film morphology is crucial to the efficient design of future OLEDs. In particular, delayed fluorescence (DF), is known to contribute a significant fraction of the light emission from polymer-based OLEDs, but its mechanism remains unclear. Here, we investigate the origin of DF in the state of the art OLED polymer Poly (9, 9-dioctylfluorene-alt-benzothiadiazole) (F8BT), under both optical and electrical excitation using time-resolved emission spectroscopy (TRES) as a function of film thickness, excitation fluence, magnetic-field, and temperature. The temperature dependence of the DF for various film thicknesses suggests that thermally activated triplet migration is the dominant process controlling DF at room temperature. We found that thermal activation energy (Eeff) of triplet migration decreases from 179 ± 31 meV to 86 ± 11 meV as film thickness varied from ~110 nm to ~560 nm, respectively. The Eeff of triplet migration is found to be a function of the molecular packing of polymer chains as determined from synchrotron grazing incidence wide angle x-ray scattering (GIWAXS) studies and steady-state photoluminescence studies. Quantum chemical calculations of reorganization energy and singlet–triplet exchange energy gap in F8BT molecule as a function of the dihedral angle between donor & acceptor moiety also confirm the experimental results. Our results show that DF in polymer OLEDs is significantly affected by parameters such as the film thickness and disorder, allowing for a high degree of control over the underlying photophysics to be achieved.
Calibration of Multi-Parameter Models of Avascular Tumor Growth Using Time Resolved Microscopy Data
Authors: Lima E. A. B. F. , Ghousifam N. , Ozkan A. , Oden J. T. , Shahmoradi A. , Rylander M. N. , Wohlmuth B. , Yankeelov T. E. 
Published: September 2018

AbstractTwo of the central challenges of using mathematical models for predicting the spatiotemporal development of tumors is the lack of appropriate data to calibrate the parameters of the model, and quantitative characterization of the uncertainties in both the experimental data and the modeling process itself. We present a sequence of experiments, with increasing complexity, designed to systematically calibrate the rates of apoptosis, proliferation, and necrosis, as well as mobility, within a phase-field tumor growth model. The in vitro experiments characterize the proliferation and death of human liver carcinoma cells under different initial cell concentrations, nutrient availabilities, and treatment conditions. A Bayesian framework is employed to quantify the uncertainties in model parameters. The average difference between the calibration and the data, across all time points is between 11.54% and 14.04% for the apoptosis experiments, 7.33% and 23.30% for the proliferation experiments, and 8.12% and 31.55% for the necrosis experiments. The results indicate the proposed experiment-computational approach is generalizable and appropriate for step-by-step calibration of multi-parameter models, yielding accurate estimations of model parameters related to rates of proliferation, apoptosis, and necrosis.
Interface Probing by Dielectric Frequency Dispersion in Carbon Nanocomposites
Authors: Li Yuhan , Qin Faxiang , Estevez Diana , Wang Huan , Peng Hua-Xin 
Published: September 2018

AbstractInterfaces remain one of the major issues in limiting the understanding and designing of polymer nanocomposites due to their complexity and pivotal role in determining the ultimate composites properties. In this study, we take multi-walled carbon nanotubes/silicone elastomer nanocomposites as a representative example, and have for the first time studied the correlation between high-frequency dielectric dispersion and static/dynamic interfacial characteristics. We have found that the interface together with other meso-structural parameters (volume fraction, dispersion, agglomeration) play decisive roles in formulating the dielectric patterns. The calculation of the relaxation times affords the relative importance of interfacial polarization to dipolar polarization in resultant dielectric relaxation. Dielectric measurements coupled with cyclic loading further reveals the remarkable capability of dielectric frequency dispersion in capturing the evolution of interfacial properties, such as a particular interface reconstruction process occurred to the surfactant-modified samples. All these results demonstrate that high-frequency dielectric spectroscopy is instrumental to probing both static and dynamic meso-structural characteristics, especially effective for the composites with relative weak interfaces which remains a mission impossible for many other techniques. The insights provided here based on the analyses of dielectric frequency dispersion will pave the way for optimized design and precise engineering of meso-structure in polymer nanocomposites.
The interplay between membrane lipids and phospholipase A family members in grapevine resistance against Plasmopara viticola
Authors: Laureano Gonçalo , Figueiredo Joana , Cavaco Ana Rita , Duarte Bernardo , Caçador Isabel , Malhó Rui , Sousa Silva Marta , Matos Ana Rita , Figueiredo Andreia 
Published: September 2018

AbstractGrapevine downy mildew, caused by the biotrophic oomycete Plasmopara viticola, is one of the most important diseases in modern viticulture. The search for sustainable disease control measure is of extreme importance, thus becoming imperative to fully characterize the mechanisms leading to an incompatible interaction. We have previously shown that lipid signalling events play an important role in grapevine’s response to this pathogen, namely through changes in linolenic acid content, lipid peroxidation and jasmonic acid synthesis. Here, we have characterized the modulation of lipid metabolism in leaves from two V. vinifera cultivars (resistant and susceptible to P. viticola) in the first hours after pathogen inoculation. Prior to pathogen inoculation both genotypes present an inherently different fatty acid composition that is highly modulated in the resistant genotype after pathogen challenge. Such changes involve modulation of phospholipase A activity suggesting that the source of lipids mobilized upon pathogen infection are the chloroplast membranes. This work thus provides original evidence on the involvement of lipid signalling and phospholipases in grapevine immune responses to pathogen infection. The results are discussed considering the implications on the plant’s physiological status and the use of discriminating lipid/fatty acids pattern in future selection procedures of cultivars.
Decomposing sensorimotor variability changes in ageing and their connection to falls in older people
Authors: Lin Chin-Hsuan , Faisal A. Aldo 
Published: September 2018

AbstractThe relationship between sensorimotor variability and falls in older people has not been well investigated. We developed a novel task having shared biomechanics of obstacle negotiation to quantify sensorimotor variability related to locomotion across age. We found that sensorimotor variability in foot placement increases continuously with age. We then applied sensory psychophysics to pinpoint the visual and somatosensory systems associated with sensorimotor variability. We showed increased sensory variability, specifically increased proprioceptive variability, the vital cause of more variable foot placement in older people (greater than 65 years). Notably, older participants relied more on the vision to judge their own foot’s height compared to the young, suggesting a shift in multisensory integration strategy to compensate for degenerated proprioception. We further modelled the probability of tripping-over based on the relationship between sensorimotor variability and age and found a correspondence between model prediction and community-based data. We reveal increased sensorimotor variability, modulated by sensation precision, a potentially vital mechanism of raised tripping-over and thus fall events in older people. Analysis of sensorimotor variability and its specific components may have the utility of fall risk and rehabilitation target evaluation.
Osteoprotegerin and Myocardial Fibrosis in Patients with Aortic Stenosis
Authors: Loudon Brodie L. , Ntatsaki Eleana , Newsome Simon , Halliday Brian , Lota Amrit , Ali Aamir , Malley Tamir , Selvendran Subothini , Aggarwal Nikhil , Lam Willis , Donovan Jackie , Auger Dominque , Raphael Claire E. , Flynn Paul D. , Pennell Dudley J. , Vassiliou Vassilios S. , Prasad Sanjay K. 
Published: September 2018

AbstractLeft ventricular myocardial fibrosis in patients with aortic stenosis (AS) confers worse prognosis. Plasma osteoprotegerin (OPG), a cytokine from the TNF receptor family, correlates with the degree of valve calcification in AS, reflecting the activity of the tissue RANKL/RANK/OPG (receptor activator of nuclear factor κΒ ligand/RANK/osteoprotegerin) axis, and is associated with poorer outcomes in AS. Its association with myocardial fibrosis is unknown. We hypothesised that OPG levels would reflect the extent of myocardial fibrosis in AS. We included 110 consecutive patients with AS who had undergone late-gadolinium contrast enhanced cardiovascular magnetic resonance (LGE-CMR). Patients were characterised according to pattern of fibrosis (no fibrosis, midwall fibrosis, or chronic myocardial infarction fibrosis). Serum OPG was measured with ELISA and compared between groups defined by valve stenosis severity. Some 36 patients had no fibrosis, 38 had midwall fibrosis, and 36 had chronic infarction. Patients with midwall fibrosis did not have higher levels of OPG compared to those without fibrosis (6.78 vs. 5.25 pmol/L, p = 0.12). There was no difference between those with midwall or chronic myocardial infarction fibrosis (6.78 vs. 6.97 pmol/L, p = 0.27). However, OPG levels in patients with chronic myocardial infarction fibrosis were significantly higher than those without fibrosis (p = 0.005).
GLS-409, an Antagonist of Both P2Y1 and P2Y12, Potently Inhibits Canine Coronary Artery Thrombosis and Reversibly Inhibits Human Platelet Activation
Authors: Smolensky Koganov Elena , Michelson Alan D. , Yanachkov Ivan B. , Yanachkova Milka I. , Wright George E. , Przyklenk Karin , Frelinger Andrew L. 
Published: September 2018

AbstractDual antiplatelet therapy with aspirin and an adenosine diphosphate (ADP) P2Y12 receptor antagonist reduces ischemic events in patients with acute coronary syndrome. Previous evidence from our group, obtained in a preclinical model of recurrent platelet-mediated thrombosis, demonstrated that GLS-409, a diadenosine tetraphosphate derivative that inhibits both P2Y1 and P2Y12 ADP receptors, may be a novel and promising antiplatelet drug candidate. However, the salutary antiplatelet effects of GLS-409 were accompanied by a trend toward an unfavorable increase in bleeding. The goals of this study were to: 1) provide proof-of-concept that the efficacy of GLS-409 may be maintained at lower dose(s), not accompanied by an increased propensity to bleeding; and 2) establish the extent and kinetics of the reversibility of human platelet inhibition by the agent. Lower doses of GLS-409 were identified that inhibited in vivo recurrent coronary thrombosis with no increase in bleeding time. Human platelet inhibition by GLS-409 was reversible, with rapid recovery of platelet reactivity to ADP, as measured by platelet surface activated GPIIb-IIIa and platelet surface P-selectin. These data support the concept that GLS-409 warrants further, larger-scale investigation as a novel, potential therapy in acute coronary syndromes.