bluuebunny/crossref_metadata_2025_split huggingface dataset:
Relation Between Near‐Fault Ground Motion Impulsive Signals and Source Parameters
Authors: Scala A. , Festa G. , Del Gaudio S. 
Published: August 2018

AbstractNear‐fault ground motion records often present impulsive signals, characterized by a large amplitude in the velocity wavefield and by the energy concentrated in a short time window as compared to the total earthquake duration. This pulse‐like behavior is ascribed to the directivity of the seismic rupture, and it requires a stronger demand to the buildings not predicted by the classical design spectra. In this work we investigate the pulse occurrence and duration in near‐fault synthetic seismograms generated from an ensemble of k−2 source models. We exploited the fault geometry of the Mw = 6.3, 2009 L'Aquila earthquake, which represents a typical example of normal‐fault earthquake for which several records in the fault vicinity are available for comparison with synthetics. We show that impulsive records are sensitive to the rupture velocity, to the hypocenter depth, and to the station location, whether it is on the hanging wall or on the footwall. The pulse duration was also shown to be proportional to the risetime, and it scales with the source‐receiver distance and inversely with the rupture velocity. We model these results as an effect of the coupled along‐strike and updip directivity.
Wave‐Equation Dispersion Inversion of Guided P Waves in a Waveguide of Arbitrary Geometry
Authors: Li Jing , Hanafy Sherif , Schuster Gerard 
Published: August 2018

AbstractWe present a dispersion‐inversion method which inverts for the P‐velocity model from guided waves propagating in wave guides of arbitrary geometry. Its misfit function is the squared summation of differences between the predicted and observed dispersion curves of guided P waves, and the inverted result is a high‐resolution estimate of the near‐surface P‐velocity model. We denote this procedure as wave‐equation dispersion inversion of guided P waves (WDG), which is valid for near‐surface waveguides with irregular layers and does not require a high‐frequency approximation. It is more robust than full waveform inversion and can sometimes provide velocity models with higher resolution than wave‐equation traveltime tomography. Both the synthetic‐data and field data results demonstrate that WDG for guided P waves can accurately invert for complex P‐velocity models at the near surface of the Earth.
Impact of a Stochastic Nonorographic Gravity Wave Parameterization on the Stratospheric Dynamics of a General Circulation Model
Authors: Serva F. , Cagnazzo C. , Riccio A. , Manzini E. 
Published: August 2018

AbstractThe general circulation of the middle atmosphere, particularly of the mesosphere, is strongly dependent on the forcing arising from gravity wave processes. Their sources in the troposphere are both orographic and nonorographic, the latter being strongly intermittent. In climate models, the effects of gravity waves need to be parameterized, often assuming that their properties are constant. In this work we focus on the changes of the middle atmosphere due to the introduction of intermittency in a parameterization of nonorographic gravity waves, using a stochastic version of the Hines scheme. The stochastic approach is tailored to the diagnosed sensitivity of the model to this forcing, and peculiar changes emerge even if a relatively small amount of intermittency is prescribed. We analyze in detail the changes of the stratospheric dynamics in the tropical region and the global circulation of the middle atmosphere, when the stochastic parameterization is employed in place of the deterministic one. The mean state and variability of the model, realistic also in the default version, are preserved when stochasticity is added. Significant changes are observed in the mesosphere due to an enhanced poleward transport, leading to warming in the winter season. While there are some improvements of the mean state, the interannual variability is not significantly affected in the extratropics. The impacts on the simulated equatorial stratosphere are evident, as the stochasticity reduces the overall period of the quasi‐biennial oscillation but also leads to a net reduction of the variability between cycles.
The cost of toxin production in phytoplankton: the case of PST producing dinoflagellates
Authors: Chakraborty Subhendu , Pančić Marina , Andersen Ken H , Kiørboe Thomas 
Published: August 2018

Abstract
Many species of phytoplankton produce toxins that may provide protection from grazing. In that case one would expect toxin production to be costly; else all species would evolve toxicity. However, experiments have consistently failed to show any costs. Here, we show that costs of toxin production are environment dependent but can be high. We develop a fitness optimization model to estimate rate, costs, and benefits of toxin production, using PST (paralytic shellfish toxin) producing dinoflagellates as an example. Costs include energy and material (nitrogen) costs estimated from well-established biochemistry of PSTs, and benefits are estimated from relationship between toxin content and grazing mortality. The model reproduces all known features of PST production: inducibility in the presence of grazer cues, low toxicity of nitrogen-starved cells, but high toxicity of P-limited and light-limited cells. The model predicts negligible reduction in cell division rate in nitrogen replete cells, consistent with observations, but &gt;20% reduction when nitrogen is limiting and abundance of grazers high. Such situation is characteristic of coastal and oceanic waters during summer when blooms of toxic algae typically develop. The investment in defense is warranted, since the net growth rate is always higher in defended than in undefended cells.
PSD95 and nNOS interaction as a novel molecular target to modulate conditioned fear: relevance to PTSD
Authors: Li L.- P. , Dustrude E. T. , Haulcomb M. M. , Abreu A. R. , Fitz S. D. , Johnson P. L. , Thakur G. A. , Molosh A. I. , Lai Y. , Shekhar A. 
Published: August 2018

AbstractStimulation of N-methyl-D-aspartic acid receptors (NMDARs) and the resulting increase of nitric oxide (NO) production are critical for fear memory formation. Following NMDAR activation, efficient production of NO requires linking the 95 kDa postsynaptic density protein (PSD95), a scaffolding protein to neuronal nitric oxide synthase (nNOS). A variety of previously studied NMDAR antagonists and NOS inhibitors can disrupt fear conditioning, but they also affect many other CNS functions such as motor activity, anxiety, and learning. We hypothesized that disrupting nNOS and PSD95 interaction in the amygdala, a critical site for fear memory formation, will reduce conditioned fear. Our results show that systemic treatment with ZL006, a compound that disrupts PSD95/nNOS binding, attenuates fear memory compared to its inactive isomer ZL007. Co-immunoprecipitation after fear conditioning showed a robust increase in the amygdala PSD95/nNOS binding, which was blocked by systemic pre-administration of ZL006. Treatment of amygdala slices with ZL006 also impaired long-term potentiation (LTP), a cellular signature of synaptic plasticity. Direct intra-amygdala infusion of ZL006 also attenuated conditioned fear. Finally, unlike NMDAR antagonist MK-801, ZL006 does not affect locomotion, social interaction, object recognition memory, and spatial memory. These findings support the hypothesis that disrupting the PSD95/nNOS interaction downstream of NMDARs selectively reduces fear memory, and highlights PSD95/nNOS interaction as a novel target for fear-related disorders, such as posttraumatic stress disorder.
Major upwelling and overturning in the mid-latitude F region ionosphere
Authors: Hysell David , Larsen Miguel , Fritts David , Laughman Brian , Sulzer Michael 
Published: August 2018

AbstractProfiles of the electron number density in the ionosphere are observed at the Arecibo Radio Observatory in Puerto Rico on a regular basis. Here, we report on recent observations showing anomalous irregularities in the density profiles at altitudes >~300 km. The irregularities occurred during a period of “mid-latitude spread F,” a space-weather phenomenon relatively common at middle latitudes in summer months characterized by instability and electron density irregularities in the bottomside of the ionospheric F layer. Remarkably, electron density irregularities extended well above the layer, through the ionization peak and into the topside which is regarded as being stable. Neither the neutral atmosphere nor the ionosphere is thought to be able to support turbulence locally at this altitude. A numerical simulation is used to illustrate how a combination of atmospheric and plasma dynamics driven at lower altitudes could explain the phenomenon.
Iron restriction inside macrophages regulates pulmonary host defense against Rhizopus species
Authors: Andrianaki Angeliki M. , Kyrmizi Irene , Thanopoulou Kalliopi , Baldin Clara , Drakos Elias , Soliman Sameh S. M. , Shetty Amol C. , McCracken Carrie , Akoumianaki Tonia , Stylianou Kostas , Ioannou Petros , Pontikoglou Charalampos , Papadaki Helen A. , Tzardi Maria , Belle Valerie , Etienne Emilien , Beauvais Anne , Samonis George , Kontoyiannis Dimitrios P. , Andreakos Evangelos , Bruno Vincent M. , Ibrahim Ashraf S. , Chamilos Georgios 
Published: August 2018

AbstractMucormycosis is a life-threatening respiratory fungal infection predominantly caused by Rhizopus species. Mucormycosis has incompletely understood pathogenesis, particularly how abnormalities in iron metabolism compromise immune responses. Here we show how, as opposed to other filamentous fungi, Rhizopus spp. establish intracellular persistence inside alveolar macrophages (AMs). Mechanistically, lack of intracellular swelling of Rhizopus conidia results in surface retention of melanin, which induces phagosome maturation arrest through inhibition of LC3-associated phagocytosis. Intracellular inhibition of Rhizopus is an important effector mechanism, as infection of immunocompetent mice with swollen conidia, which evade phagocytosis, results in acute lethality. Concordantly, AM depletion markedly increases susceptibility to mucormycosis. Host and pathogen transcriptomics, iron supplementation studies, and genetic manipulation of iron assimilation of fungal pathways demonstrate that iron restriction inside macrophages regulates immunity against Rhizopus. Our findings shed light on the pathogenetic mechanisms of mucormycosis and reveal the role of macrophage-mediated nutritional immunity against filamentous fungi.
Online search tool for graphical patterns in electronic band structures
Authors: Borysov Stanislav S. , Olsthoorn Bart , Gedik M. Berk , Geilhufe R. Matthias , Balatsky Alexander V. 
Published: August 2018

AbstractMany functional materials can be characterized by a specific pattern in their electronic band structure, for example, Dirac materials, characterized by a linear crossing of bands; topological insulators, characterized by a “Mexican hat” pattern or an effectively free electron gas, characterized by a parabolic dispersion. To find material realizations of these features, manual inspection of electronic band structures represents a relatively easy task for a small number of materials. However, the growing amount of data contained within modern electronic band structure databases makes this approach impracticable. To address this problem, we present an automatic graphical pattern search tool implemented for the electronic band structures contained within the Organic Materials Database. The tool is capable of finding user-specified graphical patterns in the collection of thousands of band structures from high-throughput calculations in the online regime. Using this tool, it only takes a few seconds to find an arbitrary graphical pattern within the ten electronic bands near the Fermi level for 26,739 organic crystals. The source code of the developed tool is freely available and can be adapted to any other electronic band structure database.
The influence of water in silicate melt on aluminium excess in plagioclase as a potential hygrometer
Authors: Fiedrich Alina M. , Martin Lukas H. J. , Storck Julian-C. , Ulmer Peter , Heinrich Christoph A. , Bachmann Olivier 
Published: August 2018

AbstractMeasuring water contents of magmas is fundamental to resolving a number of geological questions, such as the mechanisms of silicic magma evolution, the triggering of volcanic eruptions, and the formation of porphyry copper deposits. This study focuses on the correlation between apparent deviations from stoichiometry of plagioclase crystals and high water concentration in the magmatic melt from which they grew. We considered this relationship as a potential geo-hygrometer (water activity indicator). To test and potentially calibrate this new technique, a range of natural and experimental plagioclase crystals were analysed, with particular care taken to identify and avoid analytical bias and artefacts. In contrast to recently published material, we found no systematic aluminium excess in plagioclase, irrespective of the water concentration of the silicate melt it crystallised from. This suggests that aluminium excess in plagioclase cannot serve as a geo-hygrometer. The high likelihood of misinterpreting analytical artefacts (due to alkali migration and imprecise standardisation) as small deviations from stoichiometry, also requires its application as a mineral exploration tool to be treated with caution.
Ultrasensitive optical reflectivity in annular nanohole array on Photonic crystal slab based on bound states in the continuum
Authors: Li Zhijian , Zhu Qing , Wang Yaonan , Xie Suxia 
Published: August 2018

AbstractWe investigate optical bound states in the continuum (BICs) supported by a photonic crystal (PhC) slab penetrated with periodic annular holes theoretically. Ultrahigh-quality factor (Q-factor) resonances associated with BICs are obtained with a Q-factor more than 108. The BICs can be seen at nonzero incident angles by tuning the lattice constant, layer thickness, inner pillar radius and the refractive index of the surrounding medium, and figure of merit (FOM) at the BICs can reach infinite theoretically. New Fano resonance line appears with BICs when the annular hole’s symmetry is broken, which can be attributed to the change of the waveguide modes and their coupling when the annular hole shape is asymmetrical. We confirm it by tuning the inner pillars’ location and size to realize the structure’s asymmetry. It is shown the location and size asymmetry of the inner pillars inside each outer hole can impact the reflectivity and the formation of the BICs obviously. Results from finite difference time domain method (FDTD) simulation and temporal coupled mode theory (CMT) calculations agree well, which are beneficial to design elements based on optical BICs in various applications, such as biosensors, perfect filters, and waveguides.
Production of thermotolerant, detergent stable alkaline protease using the gut waste of Sardinella longiceps as a substrate: Optimization and characterization
Authors: Ramkumar Aishwarya , Sivakumar Nallusamy , Gujarathi Ashish M. , Victor Reginald 
Published: August 2018

AbstractThe gut wastes of Sardinella longiceps were used as substrate for protease production. The gut waste has 61.6% proteins, 21.8% lipids, 8.5% carbohydrates on dry weight basis and trace elements. The significant factors of protease fermentation were screened by Plackett-Burman design. A protease activity of 68.56 U/ml was predicted at 46.31 °C, incubation time 71.11 h, inoculum 4.86% (v/v) and substrate concentration 2.66% (w/v), using response surface methodology. However, the validation experiment showed 73.52 U/ml activity. The artificial neural network was found as a better tool to predict the experimental results. The partially purified protease showed higher activity at pH 9 and 10 and retained 90% activity after 120 h at pH 9. It showed maximum activity at 50 °C and retained 88% residual activity until 90 min at 50 °C. Zn++ enhanced the protease activity by 40%. The protease retained an activity of 93, 103, 90 and 98% against urea, β-mercaptoethanol, SDS and tween 80 respectively. The alkaline protease was compatible with all the commercial detergents tested with the residual activity above 90%. The alkaline protease exhibited 22% higher activity on the tryptone soya substrate. The gut waste of S. longiceps is a worthy low cost substrate for the production of industrially important alkaline protease.
ERAP1 deficient mice have reduced Type 1 regulatory T cells and develop skeletal and intestinal features of Ankylosing Spondylitis
Authors: Pepelyayeva Yuliya , Rastall David P. W. , Aldhamen Yasser A. , O’Connell Patrick , Raehtz Sandra , Alyaqoub Fadel S. , Blake Maja K. , Raedy Ashley M. , Angarita Ariana M. , Abbas Abdulraouf M. , Pereira-Hicks Cristiane N. , Roosa Sarah G. , McCabe Laura , Amalfitano Andrea 
Published: August 2018

AbstractAnkylosing spondylitis (AS) is a prototypical sero-negative autoimmune disease that affects millions worldwide. Single nucleotide polymorphisms in the Endoplasmic Reticulum Aminopeptidase 1 (ERAP1) gene have been linked to AS via GWAS studies, however, the exact mechanism as to how ERAP1 contributes to pathogenesis of AS is not understood. We undertook µCT imaging and histologic analysis to evaluate bone morphology of the axial skeletons of ERAP1−/− mice and discovered the hallmark skeletal features of AS in these mice, including spinal ankylosis, osteoporosis, and spinal inflammation. We also confirmed the presence of spontaneous intestinal dysbiosis and increased susceptibility to Dextran Sodium Sulfate (DSS)-induced colitis in ERAP1−/− mice, however the transfer of healthy microbiota from wild type mice via cross-fostering experiments did not resolve the skeletal phenotypes of ERAP1−/− mice. Immunological analysis demonstrated that while ERAP1−/− mice had normal numbers of peripheral Foxp3+ Tregs, they had reduced numbers of both “Tr1-like” regulatory T cells and tolerogenic dendritic cells, which are important for Tr1 cell differentiation. Together, our data suggests that ERAP1−/− mice may serve as a useful animal model for studying pathogenesis of intestinal, skeletal, and immunological manifestations of Ankylosing Spondylitis.
Cascaded Raman scattering based high power octave-spanning supercontinuum generation in graded-index multimode fibers
Authors: Teğin Uğur , Ortaç Bülend 
Published: August 2018

AbstractA new method to generate multi-watt-level, octave-spanning, spectrally flat supercontinua stemmed from cascaded Raman scattering in graded-index multimode fibers is reported. Formation dynamics of supercontinua are investigated by studying the effect of fiber length and core size. High power handling capacity of the graded-index multimode fibers is demonstrated by power scaling experiments. Pump pulse repetition rate is scaled from kHz to MHz while pump pulse peak power remains same and ~4 W supercontinuum is achieved with 2 MHz pump repetition rate. To the best of our knowledge, this is the highest average power and repetition supercontinuum source ever reported based on a graded-index multimode silica fiber. Spatial properties of the generated supercontinua are measured and Gaussian-like beam profiles obtained for different wavelength ranges. Numerical simulations are performed to investigate underlying nonlinear dynamics in details and well-aligned with experimental observations.
Pore cross-talk in colloidal filtration
Authors: Liot Olivier , Singh Akash , Bacchin Patrice , Duru Paul , Morris Jeffrey F. , Joseph Pierre 
Published: August 2018

AbstractBlockage of pores by particles is found in many processes, including filtration and oil extraction. We present filtration experiments through a linear array of ten channels with one dimension which is sub-micron, through which a dilute dispersion of Brownian polystyrene spheres flows under the action of a fixed pressure drop. The growth rate of a clog formed by particles at a pore entrance systematically increases with the number of already saturated (entirely clogged) pores, indicating that there is an interaction or “cross-talk” between the pores. This observation is interpreted based on a phenomenological model, stating that a diffusive redistribution of particles occurs along the membrane, from clogged to free pores. This one-dimensional model could be extended to two-dimensional membranes.
CRISPR/Cas9-Mediated Generation of Guangxi Bama Minipigs Harboring Three Mutations in α-Synuclein Causing Parkinson’s Disease
Authors: Zhu Xiang-Xing , Zhong Yi-Zhi , Ge Yao-Wen , Lu Ke-Huan , Lu Sheng-Sheng 
Published: August 2018

AbstractParkinson’s disease (PD) is a common, progressive neurodegenerative disorder characterized by classical motor dysfunction and is associated with α-synuclein-immunopositive pathology and the loss of dopaminergic neurons in the substantia nigra (SN). Several missense mutations in the α-synuclein gene SCNA have been identified as cause of inherited PD, providing a practical strategy to generate genetically modified animal models for PD research. Since minipigs share many physiological and anatomical similarities to humans, we proposed that genetically modified minipigs carrying PD-causing mutations can serve as an ideal model for PD research. In the present study, we attempted to model PD by generating Guangxi Bama minipigs with three PD-causing missense mutations (E46K, H50Q and G51D) in SCNA using CRISPR/Cas9-mediated gene editing combining with somatic cell nuclear transfer (SCNT) technique. We successfully generated a total of eight SCNT-derived Guangxi Bama minipigs with the desired heterozygous SCNA mutations integrated into genome, and we also confirmed by DNA sequencing that these minipigs expressed mutant α-synuclein at the transcription level. However, immunohistochemical analysis was not able to detect PD-specific pathological changes such as α-synuclein-immunopositive pathology and loss of SN dopaminergic neurons in the gene-edited minipigs at 3 months of age. In summary, we successfully generated Guangxi Bama minipigs harboring three PD-casusing mutations (E46K, H50Q and G51D) in SCNA. As they continue to develop, these gene editing minipigs need to be regularly teseted for the presence of PD-like pathological features in order to validate the use of this large-animal model in PD research.
Feedback Between Behavioral Adaptations and Disease Dynamics
Authors: Chen Jiangzhuo , Marathe Achla , Marathe Madhav 
Published: August 2018

AbstractWe study the feedback processes between individual behavior, disease prevalence, interventions and social networks during an influenza pandemic when a limited stockpile of antivirals is shared between the private and the public sectors. An economic model that uses prevalence-elastic demand for interventions is combined with a detailed social network and a disease propagation model to understand the feedback mechanism between epidemic dynamics, market behavior, individual perceptions, and the social network. An urban and a rural region are simulated to assess the robustness of results. Results show that an optimal split between the private and public sectors can be reached to contain the disease but the accessibility of antivirals from the private sector is skewed towards the richest income quartile. Also, larger allocations to the private sector result in wastage where individuals who do not need it are able to purchase it but who need it cannot afford it. Disease prevalence increases with household size and total contact time but not by degree in the social network, whereas wastage of antivirals decreases with degree and contact time. The best utilization of drugs is achieved when individuals with high contact time use them, who tend to be the school-aged children of large families.