bluuebunny/crossref_metadata_2025 huggingface dataset:
Confocal Micro X-Ray Fluorescence: A New Paradigm in Materials Characterization
Authors: Patterson Brian M , Havrilla George J , DeFriend Kimberly A
Published: May 2018

Micro x-ray fluorescence (MXRF) is a microscopic analysis and imaging technique that is used to characterize the elements in a material non-destructively. Micro XRF instruments use an x-ray source to shine x-rays on a sample, and a detector to detect the characteristic x-rays given off. These fluorescent x-rays have very specific energies corresponding to specific electron energy transitions. Therefore, it is possible to detect and identify all of the elements present in a sample (typically above sodium) as well as measure their concentrations. This technique is widely used for the characterization of materials including polymer and metallic foams, powder samples, forensics applications, geological samples, works of art and nuclear fuels. Commercial MXRF instruments use a fused silica optic (mono or polycapillary) to focus the x-rays on the sample with no optic on the detector (Figure 1a).
Harnessing Remote Infrasound to Study Volcanic Eruptions
Authors: Cook Terri
Published: May 2018

Data from the 2015 eruption of Chile’s Calbuco volcano suggest the international network built to monitor nuclear explosions may also be used to detect and characterize volcanic activity.
Responses of Hail and Storm Days to Climate Change in the Tibetan Plateau
Authors: Zou Tian , Zhang Qinghong , Li Wenhong , Li Jihong
Published: May 2018

There is increasing concern that local severe storm occurrence may be changing as a result of climate change. The Tibetan Plateau (TP), one of the world's most sensitive areas to climate change, became significantly warmer during recent decades. Since 1960 (1980), storm (hail) days have been decreasing by 6.2%/decade (18.3%/decade) in the region. However, what caused the frequency changes of storm and hail in the TP is largely unknown. Based on 53‐year continuous weather records at 48 TP stations and reanalysis data, we show here for the first time that the consistent decline of storm days is strongly related to a drier midtroposphere since 1960. Further analysis demonstrated that fewer hail days are driven by an elevation of the melting level (thermodynamically) and a weaker wind shear (dynamically) in a warming climate. These results imply that less storm and hail may occur over TP when climate warms.
Differences in Vertical Structure of the Madden‐Julian Oscillation Associated With the Quasi‐Biennial Oscillation
Authors: Hendon Harry H. , Abhik S.
Published: May 2018

The Madden‐Julian Oscillation (MJO) during boreal winter is more active and propagates eastward farther into the western Pacific during the easterly phase of quasi‐biennial oscillation (QBO). Using atmospheric reanalyses for 1980–2012, we show that the MJO‐induced upper tropospheric positive temperature anomaly and overriding cold cap anomaly are stronger and more in‐phase with the equatorial MJO‐convective anomaly during the easterly phase of the QBO. These temperature anomalies combine to destabilize the upper troposphere more in‐phase with MJO convection, thus acting to promote stronger MJO convection during the easterly phase of the QBO especially eastward of the Maritime Continent. This enhanced destabilization is promoted by the negative temperature anomaly at the tropopause resulting from the QBO during its easterly phase. These findings can account for the enhanced strength and farther eastward propagation of the MJO during the easterly phase of the QBO, but await confirmation by theoretical and modeling studies that can isolate these effects.
Significant Underestimation in the Optically Based Estimation of the Aerosol First Indirect Effect Induced by the Aerosol Swelling Effect
Authors: Liu Jianjun , Li Zhanqing
Published: May 2018

Aerosol optical quantities have been widely employed as the proxy variables of cloud condensation nuclei concentration to study aerosol indirect effects (AIE). Due to the aerosol swelling effect, cloud condensation nuclei and aerosol optical quantities do not vary in harmony, leading to a bias in the estimation of the AIE. To identify and quantify this artifact, we employ extensive measurements of aerosol and cloud properties made at four sites in different continents that have distinct aerosol properties in terms of size and composition. One‐unit enhancement in aerosol scattering coefficient by swelling effect is found to lead to a systematic underestimation of the first indirect effect (FIE) by about 23% that can result in an underestimation in the FIE‐related radiative forcing by several W/m2 depending on aerosol properties and relative humidity. This likely contributes significantly to the systematic difference between satellite‐based estimates of the FIE and those simulated by general circulation models. Recommendations are made to make more sound comparisons of the AIE estimated from observations and model simulations.
Observed NO/NO2 Ratios in the Upper Troposphere Imply Errors in NO‐NO2‐O3 Cycling Kinetics or an Unaccounted NOx Reservoir
Authors: Silvern R. F. , Jacob D. J. , Travis K. R. , Sherwen T. , Evans M. J. , Cohen R. C. , Laughner J. L. , Hall S. R. , Ullmann K. , Crounse J. D. , Wennberg P. O. , Peischl J. , Pollack I. B.
Published: May 2018

Observations from the SEAC4RS aircraft campaign over the southeast United States in August–September 2013 show NO/NO2 concentration ratios in the upper troposphere that are approximately half of photochemical equilibrium values computed from Jet Propulsion Laboratory (JPL) kinetic data. One possible explanation is the presence of labile NOx reservoir species, presumably organic, decomposing thermally to NO2 in the instrument. The NO2 instrument corrects for this artifact from known labile HNO4 and CH3O2NO2 NOx reservoirs. To bridge the gap between measured and simulated NO2, additional unaccounted labile NOx reservoir species would have to be present at a mean concentration of ~40 ppt for the SEAC4RS conditions (compared with 197 ppt for NOx). An alternative explanation is error in the low‐temperature rate constant for the NO + O3 reaction (30% 1‐σ uncertainty in JPL at 240 K) and/or in the spectroscopic data for NO2 photolysis (20% 1‐σ uncertainty). Resolving this discrepancy is important for understanding global budgets of tropospheric oxidants and for interpreting satellite observations of tropospheric NO2 columns.
Global Virga Precipitation Distribution Derived From Three Spaceborne Radars and Its Contribution to the False Radiometer Precipitation Detection
Authors: Wang Yu , You Yalei , Kulie Mark
Published: May 2018

This study first quantifies the virga precipitation occurrence percentage using three spaceborne radar observations, including Tropical Rainfall Measuring Mission Precipitation Radar (PR), Global Precipitation Measurement dual‐frequency PR (Ku‐band PR/Ka‐band PR [KuPR/KaPR]), and CloudSat Cloud Profiling Radar (CPR). PR and KuPR/KaPR show that virga occurrence percentage is over 30% in arid regions (e.g., Sahara desert and deserts of Australia). CPR reveals similar virga geospatial distribution. However, the virga percentage based on CPR is about twice as large as that based on PR and KuPR/KaPR due to better detection sensitivity. Results also show that the majority of the virga clouds are altostratus and cirrus. Second, we investigate the virga precipitation contribution to the passive microwave radiometer false precipitation detection. Virga precipitation accounts for as much as 50% (30%) of Tropical Rainfall Measuring Mission Microwave Imager (Global Precipitation Measurement Microwave Imager) false detection results in arid regions. The underlying reason is because precipitation detection over land primarily relies on the ice scattering signature, while virga and light precipitation (e.g., 1 mm/hr) have similar amounts of ice water path in arid regions.
Investigation of Nonlinear Output-Input Microwave Power of DMSO-Ethanol Mixture by Molecular Dynamics Simulation
Authors: Zhou Min , Cheng Ke , Sun Haoran , Jia Guozhu
Published: May 2018

The nonlinear response of output-input microwave power for DMSO-ethanol mixture, which was exhibited as the direct evidence of non-thermal effect in experiment, was investigated by molecular dynamics simulation. Effects of microwave field on the mixture were evaluated from the alteration in structure, transport, hydrogen bonding dynamics and intermolecular interaction energy. Increasing the strength of the microwave field did not lead to any markedly conformational change, but decrease the diffusion coefficient. Prolonged hydrogen bonding lifetimes, which caused by the redistribution of microwave energy, was also detected. Distinct threshold effect was observed, which was consistent with the behavior in the experiment.
A non-invasive modifiable Healthy Ageing Nutrition Index (HANI) predicts longevity in free-living older Taiwanese
Authors: Huang Yi-Chen , Wahlqvist Mark L. , Lo Yuan-Ting C. , Lin Chin , Chang Hsing-Yi , Lee Meei-Shyuan
Published: May 2018

Nutritional factors contributing to disability and mortality are modifiable in later life. Indices would add utility. We developed a gender-specific Healthy Ageing Nutrition Index (HANI) for all-cause mortality in free-living elderly. We stratified 1898 participants aged ≥65 y from the 1999–2000 Nutrition and Health Survey in Taiwan by region and randomly allocated them into development and validation sets. Linkage to the National Death Registry database until December 31, 2008 enabled mortality prediction using Cox proportional-hazards models. Four factors (appetite, eating with others, dietary diversity score, and BMI) with best total of 25 HANI points for men; and 3 factors (cooking frequency, dietary diversity score, and BMI) with best total of 27 HANI points for women, were developed. In the validation set, the highest HANI group exhibited a greater intake of plant-derived food and associated nutrients, a favourable quality of life, and more muscle mass, compared with the lowest group. The highest HANI group predicts mortality risk lower by 44 percent in men and 61 percent in women. Adjusted mortality HRs were comparable between sets. HANI is a simple, non-invasive, inexpensive, and potentially modifiable tool for nutrition monitoring and survival prediction for older adults, superior to its individual components.
Simulating reading acquisition: The link between reading outcome and multimodal brain signatures of letter–speech sound learning in prereaders
Authors: Karipidis Iliana I. , Pleisch Georgette , Brandeis Daniel , Roth Alexander , Röthlisberger Martina , Schneebeli Maya , Walitza Susanne , Brem Silvia
Published: May 2018

During reading acquisition, neural reorganization of the human brain facilitates the integration of letters and speech sounds, which enables successful reading. Neuroimaging and behavioural studies have established that impaired audiovisual integration of letters and speech sounds is a core deficit in individuals with developmental dyslexia. This longitudinal study aimed to identify neural and behavioural markers of audiovisual integration that are related to future reading fluency. We simulated the first step of reading acquisition by performing artificial-letter training with prereading children at risk for dyslexia. Multiple logistic regressions revealed that our training provides new precursors of reading fluency at the beginning of reading acquisition. In addition, an event-related potential around 400 ms and functional magnetic resonance imaging activation patterns in the left planum temporale to audiovisual correspondences improved cross-validated prediction of future poor readers. Finally, an exploratory analysis combining simultaneously acquired electroencephalography and hemodynamic data suggested that modulation of temporoparietal brain regions depended on future reading skills. The multimodal approach demonstrates neural adaptations to audiovisual integration in the developing brain that are related to reading outcome. Despite potential limitations arising from the restricted sample size, our results may have promising implications both for identifying poor-reading children and for monitoring early interventions.
Whole genome sequencing in the search for genes associated with the control of SIV infection in the Mauritian macaque model
Authors: de Manuel Marc , Shiina Takashi , Suzuki Shingo , Dereuddre-Bosquet Nathalie , Garchon Henri-Jean , Tanaka Masayuki , Congy-Jolivet Nicolas , Aarnink Alice , Le Grand Roger , Marques-Bonet Tomas , Blancher Antoine
Published: May 2018

In the Mauritian macaque experimentally inoculated with SIV, gene polymorphisms potentially associated with the plasma virus load at a set point, approximately 100 days post inoculation, were investigated. Among the 42 animals inoculated with 50 AID50 of the same strain of SIV, none of which received any preventive or curative treatment, nine individuals were selected: three with a plasma virus load (PVL) among the lowest, three with intermediate PVL values and three among the highest PVL values. The complete genomes of these nine animals were then analyzed. Initially, attention was focused on variants with a potential functional impact on protein encoding genes (non-synonymous SNPs (NS-SNPs) and splicing variants). Thus, 424 NS-SNPs possibly associated with PVL were detected. The 424 candidates SNPs were genotyped in these 42 SIV experimentally infected animals (including the nine animals subjected to whole genome sequencing). The genes containing variants most probably associated with PVL at a set time point are analyzed herein.
Assessing the Zoantharian Diversity of the Tropical Eastern Pacific through an Integrative Approach
Authors: Jaramillo Karla B. , Reverter Miriam , Guillen Paul O. , McCormack Grace , Rodriguez Jenny , Sinniger Frédéric , Thomas Olivier P.
Published: May 2018

Zoantharians represent a group of marine invertebrates widely distributed from shallow waters to the deep sea. Despite a high diversity and abundance in the rocky reefs of the Pacific Ocean, very few studies have been reported on the diversity of this group in the Tropical Eastern Pacific coasts. While molecular techniques recently clarified some taxonomic relationships within the order, the taxonomy of zoantharians is still highly challenging due to a lack of clear morphological characters and confusing use of different data in previous studies. Our first insight into the zoantharian diversity at El Pelado Marine Protected Area - Ecuador led to the identification of six species: Terrazoanthus patagonichus; Terrazoanthus sp.; Antipathozoanthus hickmani; Parazoanthus darwini; Zoanthus cf. pulchellus; and Zoanthus cf. sociatus. A metabolomic approach using UHPLC-HRMS was proven to be very efficient as a complementary tool in the systematics of these species and specialized metabolites of the ecdysteroid and alkaloid families were identified as key biomarkers for interspecific discrimination. These results show good promise for an application of this integrative approach to other zoantharians.
Functional insights into the interplay between DNA interaction and metal coordination in ferric uptake regulators
Authors: Sarvan Sabina , Charih François , Askoura Momen , Butcher James , Brunzelle Joseph S. , Stintzi Alain , Couture Jean-François
Published: May 2018

Ferric uptake regulators (Fur) are a family of transcription factors coupling gene regulatory events to metal concentration. Recent evidence has expanded the mechanistic repertoires employed by Fur to activate or repress gene expression in the presence or absence of regulatory metals. However, the mechanistic basis underlying this extended repertoire has remained largely unexplored. In this study, we used an extensive set of mutations to demonstrate that Campylobacter jejuni Fur (CjFur) employs the same surface to positively and negatively control gene expression regardless of the presence or absence of metals. Moreover, the crystal structure determination of a CjFur devoid of any regulatory metals shows that subtle reorientation of the transcription factor DNA binding domain negatively impacts DNA binding, gene expression and gut colonization in chickens. Overall, these results highlight the versatility of the CjFur DNA binding domain in mediating all gene regulatory events controlled by the metalloregulator and that the full metalation of CjFur is critical to the Campylobacter jejuni life cycle in vivo.
Energy and time optimal trajectories in exploratory jumps of the spider Phidippus regius
Authors: Nabawy Mostafa R. A. , Sivalingam Girupakaran , Garwood Russell J. , Crowther William J. , Sellers William I.
Published: May 2018

Jumping spiders are proficient jumpers that use jumps in a variety of behavioural contexts. We use high speed, high resolution video to measure the kinematics of a single regal jumping spider for a total of 15 different tasks based on a horizontal gap of 2–5 body lengths and vertical gap of +/−2 body lengths. For short range jumps, we show that low angled trajectories are used that minimise flight time. For longer jumps, take-off angles are steeper and closer to the optimum for minimum energy cost of transport. Comparison of jump performance against other arthropods shows that Phidippus regius is firmly in the group of animals that use dynamic muscle contraction for actuation as opposed to a stored energy catapult system. We find that the jump power requirements can be met from the estimated mass of leg muscle; hydraulic augmentation may be present but appears not to be energetically essential.
Systemic hypertension is not protective against chronic intraocular pressure elevation in a rodent model
Authors: van Koeverden Anna K. , He Zheng , Nguyen Christine T. O. , Vingrys Algis J. , Bui Bang V.
Published: May 2018

High intraocular pressure is the most well documented glaucoma risk factor; however many patients develop and/or show progression of glaucoma in its absence. It is now thought that in some instances, ocular perfusion pressure (blood pressure – intraocular pressure) may be as important as intraocular pressure alone. Thus, systemic hypertension would be protective against glaucoma. Epidemiological studies, however, are inconclusive. One theory of why hypertension may not protect against elevated intraocular pressure in spite of increasing ocular perfusion pressure is that with time, morphological changes to the vasculature and autoregulatory failure outweigh the benefits of improved perfusion pressure, ultimately leading to poor retinal and optic nerve head blood supply. In this study we showed the presence of increased wall:lumen ratio and wall area of the ophthalmic artery in rats with chronic hypertension in addition to failure of retinal autoregulation in response to acute modification of ocular perfusion pressure. Subsequently we found that in spite of dramatically increasing ocular perfusion pressure, chronic systemic hypertension failed to protect retinal structure and function from a rodent model of glaucoma.
Conduction in the Heart Wall: Helicoidal Fibers Minimize Diffusion Bias
Authors: Aumentado-Armstrong Tristan , Kadivar Amir , Savadjiev Peter , Zucker Steven W. , Siddiqi Kaleem
Published: May 2018

The mammalian heart must function as an efficient pump while simultaneously conducting electrical signals to drive the contraction process. In the ventricles, electrical activation begins at the insertion points of the Purkinje network in the endocardium. How does the diffusion component of the subsequent excitation wave propagate from the endocardium in a healthy heart wall without creating directional biases? We show that this is a consequence of the particular geometric organization of myocytes in the heart wall. Using a generalized helicoid to model fiber orientation, we treat the myocardium as a curved space via Riemannian geometry, and then use stochastic calculus to model local signal diffusion. Our analysis shows that the helicoidal arrangement of myocytes minimizes the directional biases that could lead to aberrant propagation, thereby explaining how electrophysiological principles are consistent with local measurements of cardiac fiber geometry. We discuss our results in the context of the need to balance electrical and mechanical requirements for heart function.
Analysis of β-tubulin-carbendazim interaction reveals that binding site for MBC fungicides does not include residues involved in fungicide resistance
Authors: Vela-Corcía David , Romero Diego , de Vicente Antonio , Pérez-García Alejandro
Published: May 2018

Methyl benzimidazole carbamate (MBC) fungicides are fungicidal compounds that exert their biological activities by preventing cell division through the inhibition of tubulin polymerization, which is the major component of microtubules. Several mutations in the β-tubulin gene contribute to MBC resistance, the most common and significant of which occur at residues 198 and 200. Despite nearly 50 years of agricultural use, the binding site of MBCs and the precise mechanism by which those mutations affect fungicide efficacy have not been determined. The aim of this work was to clarify the mode of action and the mechanism of resistance to MBC fungicides in Podosphaera xanthii, the primary causal agent of cucurbit powdery mildew, using a combination of biochemical, biophysical and computational approaches. The results allow us to propose an MBC binding site in β-tubulin that lies close to the GTP binding site and does not include residue 198 involved in MBC resistance.
Dual actions of Psalmotoxin at ASIC1a and ASIC2a heteromeric channels (ASIC1a/2a)
Authors: Liu Yi , Hagan Rebecca , Schoellerman Jeffrey
Published: May 2018

Acid-Sensing Ion Channels (ASICs) are gated by extracellular protons and play important roles in physiological and pathological states, such as pain and stroke. ASIC1a and ASIC2a, two of the most highly expressed subunits in the brain, form functional homo- and hetero-meric (ASIC1a/2a) channels. The function of ASIC1a has been widely studied using psalmotoxin (PcTx1), a venom-derived peptide, as an ASIC1a-selective antagonist. Here, using whole-cell patch clamp, we show that PcTx1 has dual actions at ASIC1a/2a. It can either inhibit or potentiate the heteromeric channel, depending on the conditioning and stimulating pHs. Potent inhibition occurs only at conditioning pHs that begin to desensitize the channel (IC50 = 2.9 nM at pH7.0, a threshold pH for desensitization of ASIC1a/2a). By contrast, potent potentiation can occur at the physiological pH in both CHO cells (EC50 = 56.1 nM) and cortical neurons (threshold concentration < 10 nM). PcTx1 potentiates ASIC1a/2a by increasing the apparent affinity of channel activation for protons. As such, potentiation is the strongest at moderate pHs, diminishing with increasing proton concentrations. Our findings identify PcTx1 as a valuable tool for studying ASIC1a/2a function and contribute significantly to the understanding of the diverse and complex pharmacology of PcTx1.
Spatial representations of the viewer’s surroundings
Authors: Shioiri Satoshi , Kobayashi Masayuki , Matsumiya Kazumichi , Kuriki Ichiro
Published: May 2018

Spatial representation surrounding a viewer including outside the visual field is crucial for moving around the three-dimensional world. To obtain such spatial representations, we predict that there is a learning process that integrates visual inputs from different viewpoints covering all the 360° visual angles. We report here the learning effect of the spatial layouts on six displays arranged to surround the viewer, showing shortening of visual search time on surrounding layouts that are repeatedly used (contextual cueing effect). The learning effect is found even in the time to reach the display with the target as well as the time to reach the target within the target display, which indicates that there is an implicit learning effect on spatial configurations of stimulus elements across displays. Since, furthermore, the learning effect is found between layouts and the target presented on displays located even 120° apart, this effect should be based on the representation that covers visual information far outside the visual field.
Species distribution model transferability and model grain size – finer may not always be better
Authors: Manzoor Syed Amir , Griffiths Geoffrey , Lukac Martin
Published: May 2018

Species distribution models have been used to predict the distribution of invasive species for conservation planning. Understanding spatial transferability of niche predictions is critical to promote species-habitat conservation and forecasting areas vulnerable to invasion. Grain size of predictor variables is an important factor affecting the accuracy and transferability of species distribution models. Choice of grain size is often dependent on the type of predictor variables used and the selection of predictors sometimes rely on data availability. This study employed the MAXENT species distribution model to investigate the effect of the grain size on model transferability for an invasive plant species. We modelled the distribution ofRhododendron ponticumin Wales, U.K. and tested model performance and transferability by varying grain size (50 m, 300 m, and 1 km). MAXENT-based models are sensitive to grain size and selection of variables. We found that over-reliance on the commonly used bioclimatic variables may lead to less accurate models as it often compromises the finer grain size of biophysical variables which may be more important determinants of species distribution at small spatial scales. Model accuracy is likely to increase with decreasing grain size. However, successful model transferability may require optimization of model grain size.
Abstract images and words can convey the same meaning
Authors: Kuipers Jan Rouke , Jones Manon Wyn , Thierry Guillaume
Published: May 2018

Intuitively, deriving meaning from an abstract image is a uniquely human, idiosyncratic experience. Here we show that, despite having no universally recognised lexical association, abstract images spontaneously elicit specific concepts conveyed by words, with a consistency akin to that of concrete images. We presented a group of naïve participants with abstract picture–word pairs construed as ‘related’ or ‘unrelated’ according to a preliminary norming procedure conducted with different participants. Surprisingly, the naïve participants with no prior exposure to the abstract images or any hints regarding their possible meaning, displayed a reaction time priming effect for ‘related’ versus ‘unrelated’ picture-word pairs. Critically, this behavioural priming effect, and an associated decrease in N400 mean amplitude indexing semantic priming, both correlated significantly with the degree of relatedness established in the preliminary norming procedure. Given that ratings and electrophysiological measures were obtained in different groups of individuals, our results show that abstract images evoke consistent meaning across observers, as has been shown in the case of music.
Superelastic and pH-Responsive Degradable Dendrimer Cryogels Prepared by Cryo-aza-Michael Addition Reaction
Authors: Wang Juan , Yang Hu
Published: May 2018

Dendrimers exhibit super atomistic features by virtue of their well-defined discrete quantized nanoscale structures. Here, we show that hyperbranched amine-terminated polyamidoamine (PAMAM) dendrimer G4.0 reacts with linear polyethylene glycol (PEG) diacrylate (575 g/mol) via the aza-Michael addition reaction at a subzero temperature (−20 °C), namely cryo-aza-Michael addition, to form a macroporous superelastic network, i.e., dendrimer cryogel. Dendrimer cryogels exhibit biologically relevant Young’s modulus, high compression elasticity and super resilience at ambient temperature. Furthermore, the dendrimer cryogels exhibit excellent rebound performance and do not show significant stress relaxation under cyclic deformation over a wide temperature range (−80 to 100 °C). The obtained dendrimer cryogels are stable at acidic pH but degrade quickly at physiological pH through self-triggered degradation. Taken together, dendrimer cryogels represent a new class of scaffolds with properties suitable for biomedical applications.
Microbial community analysis and biodeterioration of waterlogged archaeological wood from the Nanhai No. 1 shipwreck during storage
Authors: Liu Zijun , Fu Tongtong , Hu Cuiting , Shen Dawa , Macchioni Nicola , Sozzi Lorena , Chen Yue , Liu Jie , Tian Xingling , Ge Qinya , Feng Zhengteng , Liu Huiru , Zhang Zhiguo , Pan Jiao
Published: May 2018

Wooden shipwrecks are a significant part of the underwater cultural heritage. In 2007, the Nanhai No. 1 shipwreck was salvaged from the seabed and moved into the Marine Silk Road Museum, where it is still stored in a water tank. We analysed the microbial communities colonizing the hull surface of the Nanhai No. 1 shipwreck during storage. Six samples exposed to air were collected from different spots of the ship that exhibited obvious microbial plaques. High-throughput sequencing revealed the bacterial community includes both aquatic and terrestrial species, while in the fungal community, Fusarium was the most abundant genus across all samples and accounted for 84.91% to 98.40% of the total community composition. Two Fusarium species were isolated from the samples and were identified as F. solani and F. oxysporum. Both of the isolates were able to degrade cellulose, but only F. solani had the ability to degrade lignin. Antimicrobial efficacy in inhibiting the growth of Fusarium was assessed with five kinds of biocides, and isothiazolinones exhibited specific inhibition of Fusarium growth. These results provide critical background information to protect and reduce the biodegradation and destruction of this important historical shipwreck, and inform efforts to protect other similar artifacts.
Boltzmann sampling from the Ising model using quantum heating of coupled nonlinear oscillators
Authors: Goto Hayato , Lin Zhirong , Nakamura Yasunobu
Published: May 2018

A network of Kerr-nonlinear parametric oscillators without dissipation has recently been proposed for solving combinatorial optimization problems via quantum adiabatic evolution through its bifurcation point. Here we investigate the behavior of the quantum bifurcation machine (QbM) in the presence of dissipation. Our numerical study suggests that the output probability distribution of the dissipative QbM is Boltzmann-like, where the energy in the Boltzmann distribution corresponds to the cost function of the optimization problem. We explain the Boltzmann distribution by generalizing the concept of quantum heating in a single nonlinear oscillator to the case of multiple coupled nonlinear oscillators. The present result also suggests that such driven dissipative nonlinear oscillator networks can be applied to Boltzmann sampling, which is used, e.g., for Boltzmann machine learning in the field of artificial intelligence.
Transition from Spin Dewetting to continuous film in spin coating of Liquid Crystal 5CB
Authors: Dhara Palash , Bhandaru Nandini , Das Anuja , Mukherjee Rabibrata
Published: May 2018

Spin dewetting refers to spontaneous rupture of the dispensed solution layer during spin coating, resulting in isolated but periodic, regular sized domains of the solute and is pre-dominant when the solute concentration (C
n
) is very low. In this article we report how the morphology of liquid crystal (LC) 5CB thin films coated on flat and patterned PMMA substrate transform from spin dewetted droplets to continuous films with increase in C
n
. We further show that within the spin dewetted regime, with gradual increase in the solute concentration, periodicity of the isotropic droplets (λ
D
) as well as their mean diameter (d
D
), gradually decreases, till the film becomes continuous at a critical concentration (C
n
*). Interestingly, the trend that λ
D
reduces with increase in C
n
is exact opposite to what is observed in thermal/solvent vapor induced dewetting of a thin film. The spin dewetted droplets exhibit transient Radial texture, in contrast to Schlieren texture observed in elongated threads and continuous films of 5CB, which remains in the Nematic phase at room temperature. Finally we show that by casting the film on a grating patterned substrate it becomes possible to align the spin dewetted droplets along the contours substrate patterns.
Differences in pre-sleep activity and sleep location are associated with variability in daytime/nighttime sleep electrophysiology in the domestic dog
Authors: Bunford Nóra , Reicher Vivien , Kis Anna , Pogány Ákos , Gombos Ferenc , Bódizs Róbert , Gácsi Márta
Published: May 2018

The domestic dog (Canis familiaris) is a promising animal model. Yet, the canine neuroscience literature is predominantly comprised of studies wherein (semi-)invasive methods and intensive training are used to study awake dog behavior. Given prior findings with humans and/or dogs, our goal was to assess, in 16 family dogs (1.5–7 years old; 10 males; 10 different breeds) the effects of pre-sleep activity and timing and location of sleep on sleep electrophysiology. All three factors had a main and/or interactive effect on sleep macrostructure. Following an active day, dogs slept more, were more likely to have an earlier drowsiness and NREM, and spent less time in drowsiness and more time in NREM and REM. Activity also had location- and time of day-specific effects. Time of day had main effects; at nighttime, dogs slept more and spent less time in drowsiness and awake after first drowsiness, and more time in NREM and in REM. Location had a main effect; when not at home, REM sleep following a first NREM was less likely. Findings are consistent with and extend prior human and dog data and have implications for the dog as an animal model and for informing future comparative research on sleep.
Stress-associated changes in salivary microRNAs can be detected in response to the Trier Social Stress Test: An exploratory study
Authors: Wiegand Conrad , Heusser Peter , Klinger Claudia , Cysarz Dirk , Büssing Arndt , Ostermann Thomas , Savelsbergh Andreas
Published: May 2018

Stress is an important co-factor for the genesis and maintenance of many diseases and is known to have an effect on gene expression via epigenetic regulation. MicroRNAs (miRNAs) appear to function as one of the key factors of this regulation. This is the first study to investigate the response of 11 stress-associated miRNAs in human saliva - as a non-invasive source - in an experimental condition of acute psychological stress, and also their correlation with established psychological (subjective stress perception), physiological (heart rate and heart rate variability) and biochemical stress parameters (salivary cortisol and alpha-amylase). 24 healthy participants between 20 and 35 years of age were investigated, using the Trier Social Stress Test (TSST) to induce acute psychological stress. Stress-associated changes were significant for miR-20b, -21 and 26b, and changes in miR-16 and -134 were close to significance, recommending further research on these miRNAs in the context of stress reactions. Significant correlations with alpha-amylase suggest their integration in sympathetic stress regulation processes. Additionally, our results demonstrate the TSST as a reliable tool for studying salivary miRNAs as non-invasive indicators of epigenetic processes in acute psychological stress reactions.
Negative association between resilience and event-related potentials evoked by negative emotion
Authors: Chen Dan , Wu Jianhui , Yao Zhuxi , Lei Kaikai , Luo Yuejia , Li Zhihao
Published: May 2018

Individuals with low level of resilience are documented to be less capable of regulating negative emotion. To investigate the underlying neurophysiology, the present study examined the relationship between resilience and the late positive potential (LPP) evoked by emotionally negative pictures. Fifty-four participants watched negative and neutral pictures passively while their electroencephalogram (EEG) was recorded to assess LPP. Participants also completed the Connor-Davidson Resilience Scale (CD-RISC) for assessment of their resilience levels. We found that resilience was negatively correlated with the LPP response to negative emotional pictures. Additionally, this negative correlation was mainly driven by optimism, one of the three composite factors that contribute to resilience. Our results showed a neurophysiological correlate for the effect of resilience on negative emotion, and suggested a predictive value of optimism in identifying individuals potentially sensitive to affective interruptions.
Bile acids and their respective conjugates elicit different responses in neonatal cardiomyocytes: role of Gi protein, muscarinic receptors and TGR5
Authors: Ibrahim Effendi , Diakonov Ivan , Arunthavarajah Dulasi , Swift Teresa , Goodwin Mary , McIlvride Saraid , Nikolova Vanya , Williamson Catherine , Gorelik Julia
Published: May 2018

Bile acids are recognised as bioactive signalling molecules. While they are known to influence arrhythmia susceptibility in cholestasis, there is limited knowledge about the underlying mechanisms. To delineate mechanisms underlying fetal heart rhythm disturbances in cholestatic pregnancy, we used FRET microscopy to monitor cAMP release and contraction measurements in isolated rodent neonatal cardiomyocytes. The unconjugated bile acids CDCA, DCA and UDCA and, to a lesser extent, CA were found to be relatively potent agonists for the GPBAR1 (TGR5) receptor and elicit cAMP release, whereas all glyco- and tauro- conjugated bile acids are weak agonists. The bile acid-induced cAMP production does not lead to an increase in contraction rate, and seems to be mediated by the RI isoform of adenylate cyclase, unlike adrenaline-dependent release which is mediated by the RII isoform. In contrast, bile acids elicited slowing of neonatal cardiomyocyte contraction indicating that other signalling pathways are involved. The conjugated bile acids were found to be partial agonists of the muscarinic M2, but not sphingosin-1-phosphate-2, receptors, and act partially through the Gi pathway. Furthermore, the contraction slowing effect of unconjugated bile acids may also relate to cytotoxicity at higher concentrations.
Comparison of first-line and second-line terlipressin versus sole norepinephrine in fulminant ovine septic shock
Authors: Kampmeier Tim G. , Arnemann Philip H. , Hessler Michael , Seidel Laura M. , Becker Karsten , Morelli Andrea , Rehberg Sebastian W. , Ertmer Christian
Published: May 2018

The Surviving Sepsis Guidelines suggest the use of vasopressin in case of catecholamine-refractory septic shock. Terlipressin (TP) as a V1-selective AVP analogue is a potential alternative, though data regarding the first-line administration in septic shock are scarce. The present study explored and compared the effects of first-line vs. second-line infusion of TP or sole norepinephrine regarding organ function, fluid and norepinephrine requirements and survival in fulminant ovine septic shock. Peritoneal sepsis was induced in 23 ewes after laparotomy and faecal withdrawal from the caecum. After onset of shock, causal and supportive sepsis therapy (antibiotics, peritoneal lavage, fluids and open-label norepinephrine) was performed in all animals. Concurrently, animals were randomized to receive 0.9% sodium chloride (control group) or TP (2 µg∙kg−1∙h−1, first-line group) after shock onset. In the second-line TP group, TP (2 µg∙kg−1∙h−1) was started once norepinephrine requirements exceeded 0.5 µg∙kg−1∙min−1. No significant differences were found between groups regarding survival, haemodynamics as well as fluid- and catecholamine-requirements. Kidney function and electron microscopic kidney injury were comparable between groups. In the present model of fulminant ovine septic shock, first-line TP infusion had no significant effect on fluid and norepinephrine requirements or organ dysfunction as compared to second-line TP infusion or placebo.
Differential contributions of peripheral and central mechanisms to pain in a rodent model of osteoarthritis
Authors: Haywood Adrian R. , Hathway Gareth J. , Chapman Victoria
Published: May 2018

The mechanisms underlying the transition from acute nociceptive pain to centrally maintained chronic pain are not clear. We have studied the contributions of the peripheral and central nervous systems during the development of osteoarthritis (OA) pain. Male Sprague-Dawley rats received unilateral intra-articular injections of monosodium iodoacetate (MIA 1 mg) or saline, and weight-bearing (WB) asymmetry and distal allodynia measured. Subgroups of rats received intra-articular injections of, QX-314 (membrane impermeable local anaesthetic) + capsaicin, QX-314, capsaicin or vehicle on days 7, 14 or 28 post-MIA and WB and PWT remeasured. On days 7&14 post-MIA, but not day 28, QX-314 + capsaicin signficantly attenuated changes in WB induced by MIA, illustrating a crucial role for TRPV1 expressing nociceptors in early OA pain. The role of top-down control of spinal excitability was investigated. The mu-opioid receptor agonist DAMGO was microinjected into the rostroventral medulla, to activate endogenous pain modulatory systems, in MIA and control rats and reflex excitability measured using electromyography. DAMGO (3 ng) had a significantly larger inhibitory effect in MIA treated rats than in controls. These data show distinct temporal contribtuions of TRPV1 expressing nociceptors and opioidergic pain control systems at later timepoints.
Influence of Surface Roughness on Strong Light-Matter Interaction of a Quantum Emitter-Metallic Nanoparticle System
Authors: Lu Yu-Wei , Li Ling-Yan , Liu Jing-Feng
Published: May 2018

We investigate the quantum optical properties of strong light-matter interaction between a quantum emitter and a metallic nanoparticle beyond idealized structures with a smooth surface. Based on the local coupling strength and macroscopic Green’s function, we derived an exact quantum optics approach to obtain the field enhancement and light-emission spectrum of a quantum emitter. Numerical simulations show that the surface roughness has a greater effect on the near-field than on the far-field, and slightly increases the vacuum Rabi splitting on average. Further, we verified that the near-field enhancement is mainly determined by the surface features of hot-spot area.
Directional subradiance from helical-phase-imprinted multiphoton states
Authors: Jen H. H.
Published: May 2018

We theoretically investigate the far-field scattering properties of multiphoton super- and subradiant states which can be prepared by multiphoton excitations with orbital angular momentum (OAM). Due to multiphoton interference, the far-field patterns of the subradiant modes show directional scattering along the excitation direction or transverse scattering with number of peaks equal to the number of atoms. When more atoms are involved, we consider structures of stacked and concentric rings, which respectively show enhanced directional scattering and smoothed emission patterns. Our scheme gives insights to prepare many-body subradiant states, and is potentially applicable to quantum storage of multiphoton with OAM. By designing atomic spatial distributions, these cooperative states can tailor the far-field emission properties, which is useful for light collections and quantum information manipulations.
Sarcopenia as a predictor of post-transplant tumor recurrence after living donor liver transplantation for hepatocellular carcinoma beyond the Milan criteria
Authors: Kim Young Ri , Park Sukhee , Han Sangbin , Ahn Joong Hyun , Kim Seonwoo , Sinn Dong Hyun , Jeong Woo Kyoung , Ko Justin S. , Gwak Mi Sook , Kim Gaab Soo
Published: May 2018

To evaluate the association between sarcopenia and tumor recurrence after living donor liver transplantation (LDLT) in patients with advanced hepatocellular carcinoma (HCC), we analyzed 92 males who underwent LDLT for treating HCC beyond the Milan criteria. Sarcopenia was defined when the height-normalized psoas muscle thickness was <15.5 mm/m at the L3 vertebra level on computed tomography based on an optimum stratification method using the Gray’s test statistic. Survival analysis was performed with death as a competing risk event. The primary outcome was post-transplant HCC recurrence. The median follow-up time was 36 months. There was a 9% increase in recurrence risk per unit decrease in height-normalized psoas muscle thickness. Twenty-six (36.1%) of 72 sarcopenic recipients developed HCC recurrence, whereas only one (5.0%) of 20 non-sarcopenic recipients developed HCC recurrence. Recurrence risk was greater in sarcopenic patients in univariable analysis (hazard ratio [HR] = 8.06 [1.06–16.70], p = 0.044) and in multivariable analysis (HR = 9.49 [1.18–76.32], p = 0.034). Greater alpha-fetoprotein and microvascular invasion were also identified as independent risk factors. Incorporation of sarcopenia improved the model fitness and prediction power of the estimation model. In conclusion, sarcopenia appears to be one of the important host factors modulating tumor recurrence risk after LDLT for advanced HCC.
The effect of surface charge on photocatalytic degradation of methylene blue dye using chargeable titania nanoparticles
Authors: Azeez Fadhel , Al-Hetlani Entesar , Arafa Mona , Abdelmonem Yasser , Nazeer Ahmed Abdel , Amin Mohamed O. , Madkour Metwally
Published: May 2018

Herein, a simple approach based on tailoring the surface charge of nanoparticles, NPs, during the preparation to boost the electrostatic attraction between NPs and the organic pollutant was investigated. In this study, chargeable titania nanoparticles (TiΟ2 NPs) were synthesized via a hydrothermal route under different pH conditions (pH = 1.6, 7.0 and 10). The prepared TiΟ2 NPs were fully characterized via various techniques including; transmission electron microscopy (TEM), X-ray diffraction (XRD), N2 adsorption/desorption, X-ray photoelectron spectroscopy (XPS), Ultraviolet–visible spectroscopy (UV-Vis) and dynamic light scattering (DLS). The influence of the preparation pH on the particle size, surface area and band gap was investigated and showed pH-dependent behavior. The results revealed that upon increasing the pH value, the particle size decreases and lead to larger surface area with less particles agglomeration. Additionally, the effect of pH on the surface charge was monitored by XPS to determine the amount of hydroxyl groups on the TiO2 NPs surface. Furthermore, the photocatalytic activity of the prepared TiΟ2 NPs towards methylene blue (MB) photodegradation was manifested. The variation in the preparation pH affected the point of zero charge (pHPZC) of TiO2 NPs, subsequently, different photocatalytic activities based on electrostatic interactions were observed. The optimum efficiency obtained was 97% at a degradation rate of 0.018 min−1 using TiO2 NPs prepared at pH 10.
Effect of word association on linguistic event-related potentials in moderately to mildly constraining sentences
Authors: Khachatryan Elvira , Hnazaee Mansoureh Fahimi , Van Hulle Marc M.
Published: May 2018

The processing of word associations in sentence context depends on several factors. EEG studies have shown that when the expectation of the upcoming word is high (high semantic constraint), the within-sentence word association plays a negligible role, whereas in the opposite case, when there is no expectation (as in pseudo-sentences), the role of word association becomes more pronounced. However, what happens when the expectations are not high (mild to moderate semantic constraint) is not yet clear. By adopting a cross-factorial design, crossing sentence congruity with within-sentence word association, our EEG recordings show that association comes into play during semantic processing of the word only when the sentence is meaningless. We also performed an exploratory source localization analysis of our EEG recordings to chart the brain regions putatively implicated in processing the said factors and showed its complementarity to EEG temporal analysis. This study furthers our knowledge on sentence processing and the brain networks involved in it.