bluuebunny/crossref_metadata_2025 huggingface dataset:
Interoperability of Direction-Finding and Beam-Forming High-Frequency Radar Systems: An Example from the Australian High-Frequency Ocean Radar Network
Authors: Cosoli Simone , de Vos Stuart
Published: February 2019

Direction-finding SeaSonde (4.463 MHz; 5.2625 MHz) and phased-array WEllen RAdar WERA (9.33 MHz; 13.5 MHz) High-frequency radar (HFR) systems are routinely operated in Australia for scientific research, operational modeling, coastal monitoring, fisheries, and other applications. Coverage of WERA and SeaSonde HFRs in Western Australia overlap. Comparisons with subsurface currents show that both HFR types agree well with current meter records. Correlation (R), root-mean-squares differences (RMSDs), and mean bias (bias) for hourly-averaged radial currents range between R = (−0.03, 0.78), RMSD = (9.2, 30.3) cm/s, and bias = (−5.2, 5.2) cm/s for WERAs; and R = (0.1, 0.76), RMSD = (17.4, 33.6) cm/s, bias = (0.03, 0.36) cm/s for SeaSonde HFRs. Pointing errors (θ) are in the range θ = (1°, 21°) for SeaSonde HFRs, and θ = (3°, 8°) for WERA HFRs. For WERA HFR current components, comparison metrics are RU = (−0.12, 0.86), RMSDU = (12.3, 15.7) cm/s, biasU = (−5.1, −0.5) cm/s; and, RV = (0.61, 0.86), RMSDV = (15.4, 21.1) cm/s, and biasV = (−0.5, 9.6) cm/s for the zonal (u) and the meridional (v) components. Magnitude and phase angle for the vector correlation are ρ = (0.58, 0.86), φ = (−10°, 28°). Good match was found in a direct comparison of SeaSonde and WERA HFR currents in their overlap (ρ = (0.19, 0.59), φ = (−4°, +54°)). Comparison metrics at the mooring slightly decrease when SeaSonde HFR radials are combined with WERA HFR: scalar (vector) correlations for RU, V, (ρ) are in the range RU = (−0.20, 0.83), RV = (0.39, 0.79), ρ = (0.47, 0.72). When directly compared over the same grid, however, vectors from WERA HFR radials and vectors from merged SeaSonde–WERA show RU (RV) exceeding 0.9 (0.7) within the HFR grid. Despite the intrinsic differences between the two types of radars used here, findings show that different HFR genres can be successfully merged, thus increasing current mapping capability of the existing HFR networks, and minimising operational downtime, however at a likely cost of slightly decreased data quality.
Uncertainties in the Geostationary Ocean Color Imager (GOCI) Remote Sensing Reflectance for Assessing Diurnal Variability of Biogeochemical Processes
Authors: Concha Javier , Mannino Antonio , Franz Bryan , Kim Wonkook
Published: February 2019

Short-term (sub-diurnal) biological and biogeochemical processes cannot be fully captured by the current suite of polar-orbiting satellite ocean color sensors, as their temporal resolution is limited to potentially one clear image per day. Geostationary sensors, such as the Geostationary Ocean Color Imager (GOCI) from the Republic of Korea, allow the study of these short-term processes because their orbit permit the collection of multiple images throughout each day for any area within the sensor’s field of regard. Assessing the capability to detect sub-diurnal changes in in-water properties caused by physical and biogeochemical processes characteristic of open ocean and coastal ocean ecosystems, however, requires an understanding of the uncertainties introduced by the instrument and/or geophysical retrieval algorithms. This work presents a study of the uncertainties during the daytime period for an ocean region with characteristically low-productivity with the assumption that only small and undetectable changes occur in the in-water properties due to biogeochemical processes during the daytime period. The complete GOCI mission data were processed using NASA’s SeaDAS/l2gen package. The assumption of homogeneity of the study region was tested using three-day sequences and diurnal statistics. This assumption was found to hold based on the minimal diurnal and day-to-day variability in GOCI data products. Relative differences with respect to the midday value were calculated for each hourly observation of the day in order to investigate what time of the day the variability is greater. Also, the influence of the solar zenith angle in the retrieval of remote sensing reflectances and derived products was examined. Finally, we determined that the uncertainties in water-leaving “remote-sensing” reflectance (Rrs) for the 412, 443, 490, 555, 660 and 680 nm bands on GOCI are 8.05 × 10−4, 5.49 × 10−4, 4.48 × 10−4, 2.51 × 10−4, 8.83 × 10−5, and 1.36 × 10−4 sr−1, respectively, and 1.09 × 10−2 mg m−3 for the chlorophyll-a concentration (Chl-a), 2.09 × 10−3 m−1 for the absorption coefficient of chromophoric dissolved organic matter at 412 nm (ag (412)), and 3.7 mg m−3 for particulate organic carbon (POC). These Rrs values can be considered the threshold values for detectable changes of the in-water properties due to biological, physical or biogeochemical processes from GOCI.
A Comparison of the Signal from Diverse Optical Sensors for Monitoring Alpine Grassland Dynamics
Authors: Rossi Mattia , Niedrist Georg , Asam Sarah , Tonon Giustino , Tomelleri Enrico , Zebisch Marc
Published: February 2019

Grasslands cover up to 40% of the mountain areas globally and 23% of the European Alps and affect numerous key ecological processes. An increasing number of optical sensors offer a great opportunity to monitor and address dynamic changes in the growth and status of grassland vegetation due to climatic and anthropogenic influences. Vegetation indices (VI) calculated from optical sensor data are a powerful tool in analyzing vegetation dynamics. However, different sensors have their own characteristics, advantages, and challenges in monitoring vegetation over space and time that require special attention when compared to or combined with each other. We used the Normalized Difference Vegetation Index (NDVI) derived from handheld spectrometers, station-based Spectral Reflectance Sensors (SRS), and Phenocams as well as the spaceborne Sentinel-2 Multispectral Instrument (MSI) for assessing growth and dynamic changes in four alpine meadows. We analyzed the similarity of the NDVI on diverse spatial scales and to what extent grassland dynamics of alpine meadows can be detected. We found that NDVI across all sensors traces the growing phases of the vegetation although we experienced a notable variability in NDVI signals among sensors and differences among the sites and plots. We noticed differences in signal saturation, sensor specific offsets, and in the detectability of short-term events. These NDVI inconsistencies depended on sensor-specific spatial and spectral resolutions and acquisition geometries, as well as on grassland management activities and vegetation growth during the year. We demonstrated that the combination of multiple-sensors enhanced the possibility for detecting short-term dynamic changes throughout the year for each of the stations. The presented findings are relevant for building and evaluating a combined sensor approach for consistent vegetation monitoring.
Reconstructing Geostationary Satellite Land Surface Temperature Imagery Based on a Multiscale Feature Connected Convolutional Neural Network
Authors: Wu Penghai , Yin Zhixiang , Yang Hui , Wu Yanlan , Ma Xiaoshuang
Published: February 2019

Geostationary satellite land surface temperature (GLST) data are important for various dynamic environmental and natural resource applications for terrestrial ecosystems. Due to clouds, shadows, and other atmospheric conditions, the derived LSTs are often missing a large number of values. Reconstructing the missing values is essential for improving the usability of the geostationary satellite LST data. However, current reconstruction methods mainly aim to fill the values of a small number of invalid pixels with many valid pixels, which can provide useful land surface temperature values. When the missing data extent becomes large, the reconstruction effect will worsen because the relationship between different spatiotemporal geostationary satellite LSTs is complex and highly nonlinear. Inspired by the superiority of the deep convolutional neural network (CNN) in solving highly nonlinear and dynamic problems, a multiscale feature connection CNN model is proposed to fill missing LSTs with large missing regions. The proposed method has been tested on both FengYun-2G and Meteosat Second Generation-Spinning Enhanced Visible and InfraRed Imager geostationary satellite LST datasets. The results of simulated and actual experiments show that the proposed method is accurate to within about 1 °C, with 70% missing data rates. This is feasible and effective for large regions of LST reconstruction tasks.
Enabling Environments? Examining Social Co-Benefits of Ecosystem-Based Adaptation to Climate Change in Sri Lanka
Authors: Woroniecki Stephen
Published: February 2019

Climate change vulnerability and social marginalisation are often interrelated in and through environments. Variations in climate change adaptation practice and research account for such social-ecological relations to varying degrees. Advocates of ecosystem-based approaches to climate change adaptation (EbA) claim that it delivers social co-benefits to marginalised groups, although scant empirical evidence supports such claims. I investigate these claims in two EbA interventions in Sri Lanka, interpreting social benefits through an empowerment lens. I use qualitative methods such as focus groups and narrative interviews to study the conduct and context of the interventions. In both cases, marginalised people’s own empowered adaptive strategies reflect how power relations and vulnerabilities relate to dynamic ecologies. The findings show that EbA enabled social benefits for marginalised groups, especially through support to common-pool resource management institutions and the gendered practices of home gardens. Such conduct was embedded within, but mostly peripheral to, broader and deeper contestations of power. Nevertheless, projects acted as platforms for renegotiating these power relations, including through acts of resistance. The results call for greater recognition of the ways that marginalised groups relate to ecology within empowered adaptive strategies, whilst also highlighting the need to recognise the diverse interests and power relations that cut across the conduct and contexts of these nominally ecosystem-based interventions.
Scenario Analysis–Based Decision and Coordination in Supply Chain Management with Production and Transportation Scheduling
Authors: Jiang Yang , Zhou Xiaoye , Xu Qi
Published: February 2019

The production and rail transportation coordinating problem aims to determine a pre-operational timetable for a set of orders. The orders need to be manufactured on a dedicated production line and be delivered to their destination by the pre-planned trains considering traveling routes and time. The connecting trains are an important and even unique chance for orders to reach their final destinations, and earliness and tardiness penalties in the connection and delivery process are closely related to the symmetry and harmony between production procedure decision and train-allocated choice. A scenario analysis method is adopted to reveal the relationships between production collection connecting time (PCCT) and production collection waiting time (PCWT) in the production process. In the delivery process, the relationships between production delivery connecting time (PDCT) and production delivery waiting time (PDWT) are mainly considered. An integrated scheduling coordination model is established to maximize the production connecting time (PCT) and production delivery time (PDT). The GA genetic algorithm is employed to solve this problem. The numerical results show that the coordinated schedule in our method can significantly reduce the number of missed connections when compared with considering delivery timeliness only through a delivery time window. Additionally, it is revealed that the quantitative performances of the delivery timeliness improved by the connecting quality (PCT) are much better than those from the view of the delivery time window (PDT).
Multi-Objective Parameter Optimization for Disc Milling Process of Titanium Alloy Blisk Channels
Authors: Li Zhishan , Shi Yaoyao
Published: February 2019

The blisk has been widely used in modern high performance aero-engines of high thrust-weight ratio. Disc milling process provides a reliable way to improve the efficiency of the blisk milling. The process parameters of disc milling have crucial effects on the milling efficiency and physical property of blisk. In this paper, material removal rate, cutter life and thickness of residual stress layer are regarded as optimization targets the key process parameters such as spindle speed, cutting depth and feed speed are optimized. Based on the grey relational analysis, the multi-objective optimization problem is transformed into a single objective optimization problem. At the same time, the problem of non-symmetry influence of key process parameters on optimization targets can be solved. And the influence weight of material removal rate, cutter life and thickness of residual stress layer on the grey relational grade (GRG) are calculated according to principal component analysis. The second order prediction model of GRA is developed by response surface method. On the basis of verifying the accuracy of the model, the influence mechanism of the process parameters coupling on the gray correlation degree is analyzed the optimal process parameter combination is obtained as spindle speed with 81.92 rpm, cutting depth with 5.88 mm and feed rate with 66.0823 mm/min. The experimental research show that the optimal process parameter combination can effectively improve the material removal rate and cutter life and reduce the thickness of residual stress layer.
A Long-Term Time Series of Dinophysis acuminata Blooms and Associated Shellfish Toxin Contamination in Port Underwood, Marlborough Sounds, New Zealand
Authors: Mackenzie Lincoln A.
Published: February 2019

Blooms of the dinoflagellate Dinophysis acuminata occur every year in an important mussel cultivation area in Port Underwood, Marlborough Sounds, New Zealand. Annual maximum cell numbers range from 1500–75,000 cells L−1 and over 25 years of weekly monitoring the D. acuminata bloom has never failed to exhibit peaks in abundance at some time between spring and autumn. During winter (June–August) the dinoflagellate is often undetectable, or at low levels (≤100 cells L−1), and the risk of diarrhetic shellfish poisoning (DSP)-toxin contamination over this period is negligible. Bloom occurrence may be coupled to the abundance of D. acuminata prey (Mesodinium sp.) but the mechanism by which it maintains its long-term residence in this hydrologically dynamic environment is unknown. The toxin profile of D. acuminata is dominated by pectenotoxin-2 (PTX-2) and dinophysistoxin-1 (DTX-1), but the cellular toxin content is low. It is rare that free DTX-1 is detected in mussels as this is invariably exclusively present as fatty acid-esters. In only five out of >2500 mussel samples over 16 years have the levels of total DTX-1 marginally exceeded the regulated level of 0.16 mg kg−1. It is also rare that free PTX-2 is detected in mussels, as it is generally only present in its hydrolysed non-toxic PTX-2 seco acid form. The D. acuminata alert level of 1000 cells L−1 is often exceeded without DTX-1 residues increasing appreciably, and this level is considered too conservative.
Transcriptional Regulation of Aflatoxin Biosynthesis and Conidiation in Aspergillus flavus by Wickerhamomyces anomalus WRL-076 for Reduction of Aflatoxin Contamination
Authors: Hua Sui Sheng T. , Sarreal Siov Bouy L. , Chang Perng-Kuang , Yu Jiujiang
Published: February 2019

Aspergillus flavus is a ubiquitous saprophytic fungus found in soils across the world. The fungus is the major producer of aflatoxin (AF) B1, which is toxic and a potent carcinogen to humans. Aflatoxin B1 (AFB1) is often detected in agricultural crops such as corn, peanut, almond, and pistachio. It is a serious and recurrent problem and causes substantial economic losses. Wickerhamomyces anomalus WRL-076 was identified as an effective biocontrol yeast against A. flavus. In this study, the associated molecular mechanisms of biocontrol were investigated. We found that the expression levels of eight genes, aflR, aflJ, norA, omtA, omtB, pksA, vbs, and ver-1 in the aflatoxin biosynthetic pathway cluster were suppressed. The decreases ranged from several to 10,000 fold in fungal samples co-cultured with W. anomalus. Expression levels of conidiation regulatory genes brlA, abaA, and wetA as well as sclerotial regulatory gene (sclR) were all down regulated. Consistent with the decreased gene expression levels, aflatoxin concentrations in cultural medium were reduced to barely detectable. Furthermore, fungal biomass and conidial number were significantly reduced by 60% and more than 95%, respectively. The results validate the biocontrol efficacy of W. anomalus WRL-076 observed in the field experiments.
Status of Schistosomiasis Elimination in the Caribbean Region
Authors: Hewitt Reynold , Willingham Arve Lee
Published: February 2019

Schistosomiasis elimination status in the Caribbean is reviewed with information on historical disease background, attempts to control it and current situation for each locality in the region where transmission has been eliminated (Sint Maarten, Saint Kitts, Vieques), eliminated but not yet verified (Puerto Rico, Dominican Republic, Antigua, Montserrat, Guadeloupe, Martinique) and still ongoing (Saint Lucia, Suriname). Integrated control initiatives based on selective and mass treatment and snail control using environmental, chemical and biological methods along with public service improvements (housing, safe water, sanitation) and changes in demography (urbanization) and economy (change from sugarcane and banana production to tourism) have resulted in reduction in the burden of schistosomiasis over the past century. Introduction of Biomphalaria-competitor snails into the region as a cost-effective, low maintenance control method appears to have had the most sustainable impact on transmission reduction. A regional inventory of B. glabrata, other Biomphalaria species and Biomphalaria-competitor snails as well as investigation of possible animal reservoir hosts in persisting endemic areas would be helpful for control. Elimination of schistosomiasis appears achievable in the Caribbean. However, a regional surveillance and monitoring program is needed to verify elimination in the various localities and identify and monitor areas still endemic or at risk.
Twelfth International Foamy Virus Conference—Meeting Report
Authors: Herchenröder Ottmar , Löchelt Martin , Buseyne Florence , Gessain Antoine , Soares Marcelo A. , Khan Arifa S. , Lindemann Dirk
Published: February 2019

The 12th International Foamy Virus Conference took place on 30–31 August 2018 at the Technische Universität Dresden, Dresden, Germany. The meeting included presentations on current research on non-human primate and non-primate foamy viruses (FVs; also called spumaretroviruses) as well as keynote talks on related research areas in retroviruses. The taxonomy of foamy viruses was updated earlier this year to create five new genera in the subfamily, Spumaretrovirinae, based on their animal hosts. Research on viruses from different genera was presented on topics of potential relevance to human health, such as natural infections and cross-species transmission, replication, and viral-host interactions in particular with the immune system, dual retrovirus infections, virus structure and biology, and viral vectors for gene therapy. This article provides an overview of the current state-of-the-field, summarizes the meeting highlights, and presents some important questions that need to be addressed in the future.
Evaluation of Fengyun-3C Soil Moisture Products Using In-Situ Data from the Chinese Automatic Soil Moisture Observation Stations: A Case Study in Henan Province, China
Authors: Zhu Yongchao , Li Xuan , Pearson Simon , Wu Dongli , Sun Ruijing , Johnson Sarah , Wheeler James , Fang Shibo
Published: February 2019

Soil moisture (SM) products derived from passive satellite missions are playing an increasingly important role in agricultural applications, especially crop monitoring and disaster warning. Evaluating the dependability of satellite-derived soil moisture products on a large scale is crucial. In this study, we assessed the level 2 (L2) SM product from the Chinese Fengyun-3C (FY-3C) radiometer against in-situ measurements collected from the Chinese Automatic Soil Moisture Observation Stations (CASMOS) during a one-year period from 1 January 2016 to 31 December 2016 across Henan in China. In contrast, we also investigated the skill of the Advanced Microwave Scanning Radiometer 2 (AMSR2) and Soil Moisture Active/Passive (SMAP) SM products simultaneously. Four statistical parameters were used to evaluate these products’ reliability: mean difference, root-mean-square error (RMSE), unbiased RMSE (ubRMSE), and the correlation coefficient. Our assessment results revealed that the FY-3C L2 SM product generally showed a poor correlation with the in-situ SM data from CASMOS on both temporal and spatial scales. The AMSR2 L3 SM product of JAXA (Japan Aerospace Exploration Agency) algorithm had a similar level of skill as FY-3C in the study area. The SMAP L3 SM product outperformed the FY-3C temporally but showed lower performance in capturing the SM spatial variation. A time-series analysis indicated that the correlations and estimated error varied systematically through the growing periods of the key crops in our study area. FY-3C L2 SM data tended to overestimate soil moisture during May, August, and September when the crops reached maximum vegetation density and tended to underestimate the soil moisture content during the rest of the year. The comparison between the statistical parameters and the ground vegetation water content (VWC) further showed that the FY-3C SM product performed much better under a low VWC condition (<0.3 kg/m2) than a high VWC condition (>0.3 kg/m2), and the performance generally decreased with increased VWC. To improve the accuracy of the FY-3C SM product, an improved algorithm that can better characterize the variations of the ground VWC should be applied in the future.
Commercial Tanker Water Demand in Amman, Jordan—A Spatial Simulation Model of Water Consumption Decisions under Intermittent Network Supply
Authors: Zozmann Heinrich , Klassert Christian , Sigel Katja , Gawel Erik , Klauer Bernd
Published: February 2019

The Hashemite Kingdom of Jordan is confronted with a severe freshwater crisis shaped by excess water demand and intermittent public supply. In Jordan’s capital and most populous city, Amman, the pervasive water shortage gave rise to private tanker water operations, which transport groundwater from wells in the vicinity of the city and sell it to urban consumers. These tanker water markets have received little attention in the literature up to date, particularly with regard to their relevance for commercial water users. This paper aims to empirically estimate the water demand of commercial establishments in Amman under public supply rationing and to assess to which extent tanker operations contribute to meeting commercial water needs. Building on a prior simulation model of residential water consumption, the results of three extensive surveys concerned with tanker water markets and various geographic data, we develop a spatial agent-based model of the water consumption behavior of commercial establishments in different sizes. According to our estimation, 35–45% of the overall water volume consumed by the commercial sector stems from tanker operations, depending on the season. We find that the local disparities in access to affordable network water, along with the dispersion of groundwater wells around the city, result in considerable spatial differences in tanker water consumption. The outcome of this analysis could be relevant for policy attempting to enhance freshwater sustainability in Jordan.
THE KNOWLEDGE-BASED ECONOMY IN LITHUANIA: ANALYSIS OF TENDENCIES
Authors: Ginevičius Romualdas , Korsakiene Renata
Published: February 2019

The purpose of this paper is to analyse the tendencies of knowledge‐based economy in Lithuania by looking at a knowledge economy's major dimensions ‐ the structure of economic activity and the infrastructure of knowledge economy. The knowledge‐based economy is the dominant post‐industrial economic development paradigm. The emergence of this paradigm in the 1980s created preconditions to emphasize the role of knowledge creation and distribution as the primary driver in the process of economic development and growth, the distribution of income, development of knowledge‐based networks among firms and the interface between government, business and citizens in the advanced economies.
In-flight Characterization and Calibration of the Juno-ultraviolet Spectrograph (Juno-UVS)
Authors: Hue Vincent , Randall Gladstone G. , Greathouse Thomas K. , Kammer Joshua A. , Davis Michael W. , Bonfond Bertrand , Versteeg Maarten H. , Grodent Denis C. , Gérard Jean-Claude , Bolton Scott J. , Levin Steven M. , Byron Ben D.
Published: February 2019

Juno is the first polar orbiter around Jupiter. Juno possesses a suite of instruments designed to measure the electron and ion populations in the Jupiter magnetosphere, leading to the powerful Jovian aurorae. The Ultraviolet Spectrograph onboard Juno (Juno-UVS) is a photon-counting imaging spectrograph (68–210 nm), designed to observe and characterize Jupiter’s far-ultraviolet aurorae. The instrument borrows heavily from previous Alice and UVS instruments led by Southwest Research Institute (New Horizons and Rosetta Alices, LRO-LAMP), with several major improvements. The pointing flexibility offered by the UVS scan mirror combined with Juno’s spin allows UVS access to half of the sky at any given moment. This paper describes how we leverage this extensive database to track the evolution of Juno-UVS calibration with time throughout the mission. UVS observes 7.2° × 360°-long swaths of the sky for each rotation of the spacecraft (nominally 2 rpm). This paper describes how the very substantial amount of stellar spectra has been used to monitor the health of the instrument over the mission. As of PJ14 (2018 July 16), more than 8700 spectra of O, A, and B stars have been extracted in the V-magnitude range of ∼0–7, and more than 99% of the sky was mapped. Selected stars among this list were used to calibrate the UVS bandpass, using observations from the International Ultraviolet Explorer and the Hubble Space Telescope. The retrieved effective area of the instrument is 0.30 ± 0.03 cm2 at 125 nm, 0.15 ± 0.02 cm2 at 140 nm, and 0.05 ± 0.01 cm2 at 160 nm.
Rotational Light Curves of Jupiter from Ultraviolet to Mid-infrared and Implications for Brown Dwarfs and Exoplanets
Authors: Ge 葛 Huazhi 華志 , Zhang Xi , Fletcher Leigh N. , Orton Glenn S. , Sinclair James , Fernandes Josh , Momary Tom , Kasaba Yasumasa , Sato Takao M. , Fujiyoshi Takuya
Published: February 2019

Rotational modulations are observed on brown dwarfs and directly imaged exoplanets, but the underlying mechanism is not well understood. Here we analyze Jupiter’s rotational light curves at 12 wavelengths from the ultraviolet (UV) to the mid-infrared (mid-IR). The peak-to-peak amplitudes of Jupiter’s light curves range from subpercent to 4% at most wavelengths, but the amplitude exceeds 20% at 5 μm, a wavelength sensing Jupiter’s deep troposphere. Jupiter’s rotational modulations are primarily caused by discrete patterns in the cloudless belts instead of the cloudy zones. The light-curve amplitude is controlled by the sizes and brightness contrasts of the Great Red Spot (GRS), expansions of the North Equatorial Belt (NEB), patchy clouds in the North Temperate Belt (NTB), and a train of hot spots in the NEB. In reflection, the contrast is controlled by upper tropospheric and stratospheric hazes, clouds, and chromophores in the clouds. In thermal emission, the small rotational variability is caused by the spatial distribution of temperature and opacities of gas and aerosols; the large variation is caused by the NH3 cloud holes and thin-thick clouds. The methane-band light curves exhibit opposite-shape behavior compared with the UV and visible wavelengths, caused by a wavelength-dependent brightness change of the GRS. Light-curve evolution is induced by periodic events in the belts and longitudinal drifting of the GRS and patchy clouds in the NTB. This study suggests several interesting mechanisms related to distributions of temperature, gas, hazes, and clouds for understanding the observed rotational modulations on brown dwarfs and exoplanets.
Apsidal Motion and Absolute Parameters of 21 Early-type Small Magellanic Cloud Eccentric Eclipsing Binaries
Authors: Zasche P. , Wolf M.
Published: February 2019

We present the apsidal motion and light-curve analyses of 21 eccentric eclipsing binaries located in the Small Magellanic Cloud. Most of these systems have never been studied before, hence their orbital and physical properties as well as the apsidal motion parameters are given here for the first time. All the systems are of early spectral type, having orbital periods up to 4 days. The apsidal motion periods were derived to be from 7.2 to 200 yr (OGLE-SMC-ECL-2194 having the shortest apsidal period among known main-sequence systems). The orbital eccentricities are usually rather mild (median of about 0.06), the maximum eccentricity being 0.33. For the period analysis using O − C diagrams of eclipse timings, in total 951 minima were derived from survey photometry as well as our new data. Moreover, six systems show some additional variation in their O − C diagrams, which should indicate the presence of hidden additional components in them. According to our analysis these third-body variations have periods from 6.9 to 22 yr.
SN Ia Standardization on the Rise: Evidence for the Cosmological Importance of Pre-maximum Measurements
Authors: Hayden B. , Rubin D. , Strovink M.
Published: February 2019

We present SALT2X, an extension of the SALT2 model for SN Ia light curves. SALT2X separates the light-curve-shape parameter x
1 into an

and

for the rise and fall portions of the light curve. Using the Joint Lightcurve Analysis SN sample, we assess the importance of the rising and falling portions of the light curve for cosmological standardization using a modified version of the Unified Nonlinear Inference for Type Ia cosmologY (UNITY) framework. We find strong evidence that

has a stronger correlation with peak magnitude than

. We see evidence that standardizing on the rise affects the color standardization relation, and reduces the size of the host-galaxy standardization and the unexplained (“intrinsic”) luminosity dispersion. Since SNe Ia generally rise more quickly than they decline, a faster observing cadence in future surveys will be necessary to maximize the gain from this work and to continue to explore the impacts of decoupling the rising and falling portions of SN Ia light curves.
A Hint of Three-section Halo As Seen from the APOGEE DR14
Authors: Chen Y. Q. , Zhao G. , Xue X. X. , Zhao J. K. , Liang X. L. , Jia Y. P. , Yang C. Q.
Published: February 2019

Based on the [M/H] versus [Mg/Fe] diagram and distances from APOGEE data release 14, we compare the spatial distributions, the l − V
los diagram, and the abundance gradients between high-[Mg/Fe] and low-[Mg/Fe] sequences. The two sequences are clearly shown at

in the metallicity range of −1.6 < [M/H] < −0.7, where the halo at

consists of low-[Mg/Fe] stars only. In the intermediate-metallicity range of −1.1 < [M/H] < −0.7, a [Mg/Fe] gradient is detected for stars at

and it flattens out at

. The l − V
los diagram is adopted to separate halo stars from the disk by defining the transition metallicity, which is of [M/H] ∼ −1.1 ± 0.05 dex for the high-[Mg/Fe] sequence and of [M/H] ∼ −0.7 ± 0.05 dex for the low-[Mg/Fe] sequence. The R and

distributions for the high-[Mg/Fe] sequence, the thick disk at −1.1 < [M/H] < −0.7 and the in situ halo at −1.6 < [M/H] < −1.1, have a cutoff at R ∼ 15 kpc and

, beyond which low-[Mg/Fe] halo stars are the main contributions. In the metallicity range of −1.6 < [M/H] < −0.7, there is a negative metallicity gradient for the high-[Mg/Fe] halo at

, while only a marginal or no slope in the [M/H] versus

diagram for the low-[Mg/Fe] halo at

, beyond which both the high-[Mg/Fe] halo and low-[Mg/Fe] halo flatten out toward

. These results indicate a complicated formation history of the Galaxy and we may see a hint of a three-section halo, i.e., the inner in situ halo within

, the intermediately outer dual-mode halo at

, and the extremely outer accreted halo with

.
Constraining the Magnetic Field of the Smith High-velocity Cloud Using Faraday Rotation
Authors: Betti S. K. , Hill Alex S. , Mao S. A. , Gaensler B. M. , Lockman Felix J. , McClure-Griffiths N. M. , Benjamin Robert A.
Published: February 2019

The Smith Cloud is a high-velocity cloud with an orbit suggesting it has made at least one passage through the Milky Way disk. A magnetic field found around this cloud has been thought to provide extra stability as it passes through the Galactic halo. We use the Karl G. Jansky Very Large Array to measure Faraday rotation measures (RMs) toward 1105 extragalactic background point sources behind and next to the Smith Cloud to constrain the detailed geometry and strength of its magnetic field. The RM pattern across the cloud gives the detailed morphology of the magnetic field structure, which indicates a field draped over the ionized gas and compressed at the head of the cloud. We constrain the peak line-of-sight magnetic field strength to ≳+5 μG and create a model of the magnetic field to demonstrate that a draped configuration can qualitatively explain the morphology of the observed RMs.
Comprehensive Analysis of the Formation of a Shock Wave Associated with a Coronal Mass Ejection
Authors: Frassati Federica , Susino Roberto , Mancuso Salvatore , Bemporad Alessandro
Published: February 2019

On 2014 November 1, a solar prominence eruption associated with a C2.7 class flare and a type II radio burst resulted in a fast partial halo coronal mass ejection (CME). Images acquired in the extreme ultraviolet (EUV) by the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) and PROBA2/SWAP and in white light (WL) by Solar and Heliospheric Observatory/Large Angle and Spectrometric Coronagraph show the expansion of a bright compression front ahead of the CME. In this work, we present a detailed investigation of the CME-driven shock associated with this event following the early evolution of the compression front observed near the Sun up to the extended corona. Our aim is to shed light on the long-debated issue concerning the location and timing of shock formation in the corona. Through differential emission measure analysis, we derived, for the first time, the compression ratio across the expanding EUV front observed by AIA at different temperature ranges: higher compression ratios corresponded to higher plasma temperature ranges, as expected. Moreover, comparison between up- and downstream temperatures and those expected via adiabatic compression shows that no additional heating mechanisms occurred in the early front expansion phase, implying that the shock formed beyond the AIA field of view. Finally, the analysis of the associated type II radio burst, in combination with the inferred coronal density distribution, allowed us to identify a well-defined region located northward of the CME source region as the site for shock formation and to outline its kinematics in accordance with the evolution of the expanding front as obtained from the EUV and WL data.
Detection of a Gamma-Ray Flare from the High-redshift Blazar DA 193
Authors: Paliya Vaidehi S. , Ajello M. , Ojha R. , Angioni R. , Cheung C. C. , Tanada K. , Pursimo T. , Galindo P. , Losada I. R. , Siltala L. , Djupvik A. A. , Marcotulli L. , Hartmann D.
Published: February 2019

High-redshift (z > 2) blazars are the most powerful members of the blazar family. Yet, only a handful of them have both X-ray and γ-ray detection, thereby making it difficult to characterize the energetics of the most luminous jets. Here, we report, for the first time, the Fermi-Large Area Telescope detection of the significant γ-ray emission from the high-redshift blazar DA 193 (z = 2.363). Its time-averaged γ-ray spectrum is soft (γ-ray photon index = 2.9 ± 0.1), and together with a relatively flat hard X-ray spectrum (14–195 keV photon index = 1.5 ± 0.4), DA 193 presents a case to study a typical high-redshift blazar with inverse Compton peak being located at MeV energies. An intense GeV flare was observed from this object in the first week of 2018 January, a phenomenon rarely observed from high-redshift sources. What makes this event a rare one is the observation of an extremely hard γ-ray spectrum (photon index = 1.7 ± 0.2), which is somewhat unexpected because high-redshift blazars typically exhibit a steep falling spectrum at GeV energies. The results of our multifrequency campaign, including both space- (Fermi, NuSTAR, and Swift) and ground-based (Steward and Nordic Optical Telescope) observatories are presented, and this peculiar γ-ray flare is studied within the framework of a single-zone leptonic emission scenario.
Flare and Warp of Galactic Disk with OB Stars from Gaia DR2
Authors: Li Chengdong , Zhao Gang , Jia Yunpeng , Liao Shilong , Yang Chengqun , Wang Qixun
Published: February 2019

The OB stars are selected from the Gaia DR2 catalog to explore the flare and warp of the Galactic disk in this work. The Gaia and 2MASS photometric information is adopted as the criteria to choose the sample stars. We model the Galactic disk stellar distribution in this work taking the flare and warp into consideration. The parameters in the flare and warp model are acquired directly by fitting the stars with the stellar distribution function of the disk. We obtain that the scale length of the Galactic disk in space density is 2.10 ± 0.01 kpc. We find that the disk scale height increases with Galactic radius via fitting our sample stars perpendicular to the Galactic plane. The scale height of OB stars increases more moderately than old stellar populations in the disk. It is also concluded that the inner disk is flat and begins to warp at about 9 kpc away from Galactic center. The warp amplitude of OB stars is similar to pulsars and slowly increases along the Galactic radius.
Line-of-Sight Gas Sloshing in the Cool Core of Abell 907
Authors: Ueda Shutaro , Ichinohe Yuto , Kitayama Tetsu , Umetsu Keiichi
Published: February 2019

We present line-of-sight (LOS) gas sloshing first found in a cool core in a galaxy cluster. The galaxy cluster Abell 907 is identified as a relaxed cluster owing to its global X-ray surface brightness taken by the Chandra X-ray Observatory. The X-ray residual image after removing the global emission of the intracluster medium (ICM), however, shows an arc-like positive excess and a negative excess surrounding the central positive excess in the cluster core, which in turn indicates a disturbance of the ICM. We analyze the X-ray spectra extracted from both regions and find that (1) the ICM temperature and the metal abundance in the positive excess are lower and higher than those in the negative excess, respectively, and (2) the ICM is nearly in pressure equilibrium. We also find a slight redshift difference between the positive and the negative excesses, which corresponds to the velocity shear of

km s−1 (1σ). The X-ray residual image and the ICM properties are consistent with those expected by LOS gas sloshing. Assuming that the gas is moving inverse-parallel to each other along the LOS, the shear velocity is expected to be ∼800 km s−1. The velocity field of this level is able to provide nonthermal pressure support by ∼34% relative to the thermal one. The total kinetic energy inferred from the shear velocity corresponds to ∼30% of the bolometric luminosity of the sloshing ICM. Abell 907 is therefore complementary to galaxy clusters in which gas sloshing takes place in the plane of the sky, and is important for understanding gas dynamics driven by sloshing and its influence on the heating to prevent runaway cooling.
Alfvénicity of Quiet-Sun-associated Wind during Solar Maximum
Authors: Wang Xin , Zhao Liang , Tu Chuanyi , He Jiansen
Published: February 2019

The quiet Sun (QS) and helmet streamer (STR) are generally considered to account for sources of slow solar wind with low Alfvénicity and low proton temperature. The solar wind with high Alfvénicity is often associated with coronal holes (CHs). Recently, the solar wind measured by the Advanced Composition Explorer spacecraft at 1 au was mapped back to its magnetic footpoints. Depending on the proximity of the solar wind footpoints to a given coronal or heliospheric structure, we classify solar winds into different types based on their sources: QS, STR, active region (AR), and CH. Here, we compare the properties of the solar winds originated from QS, STR, AR, and CH using 2 hr data. We find that at solar maximum 34% of the quiet-Sun-associated slow wind (V
SW < 450 km s−1) has high Alfvénicity (

). This significantly higher proportion of Alfvénic fluctuations indicates that the quiet-Sun-associated wind at 1 au has similar properties as fast wind, which originates from the CH. Accordingly, we speculate that this type of solar wind at 1 au could come from open fields within the quiet-Sun region. This observational study will help us understand more about the coronal source regions of the solar wind in interplanetary space.
Frequent Flare Events on the Short-period M-type Eclipsing Binary BX Tri
Authors: Luo ChangQing , Zhang XiaoBin , Wang Kun , Liu Chao , Fang Xiangsong , Zhang Chunguang , Deng Licai , Nie Jundan , Fox-Machado Lester , Luo Yangping , Niu Hubiao
Published: February 2019

We present long-term, multicolor photometric monitoring and spectroscopic observations of the short-period M-type eclipsing binary BX Tri. Six flare events were recorded over four years from 2014 to 2017. Three of them were detected on one night within an orbital cycle. The strongest one was identified on 2014 December 23. With the amplitudes ΔB = 0.48 mag, ΔV = 0.28 mag, ΔR = 0.10 mag, and ΔI = 0.02 mag, the total energy due to the flare event was measured to be 4.08 (±0.24) × 1034 erg, exceeding the superflare level (1034). Based on the observations, the evolutionary status of the binary system and the long-term orbital period changes were analyzed. It reveals that BX Tri is probably a semidetached system with the primary component filling its Roche lobe. The extremely high occurrence of flare events in the binary could be related to rapid mass transfer between the components.
Line Identification of Atomic and Ionic Spectra of Holmium in the Visible Spectral Range. I. Spectrum of Ho i
Authors: Özdalgiç B. , Güzelçİmen F. , Öztürk I. K. , Kröger S. , Kruzins A. , Tamanis M. , Ferber R. , Başar Gö.
Published: February 2019

Spectra of a holmium hollow cathode discharge lamp with neon or argon as buffer gases have been measured with a Fourier Transform spectrometer. In the visible spectral range from 14,280 up to 25,000 cm−1, or 400 to 700 nm, more than 4000 spectral lines were detected. Based on different signal-to-noise ratios in two spectra measured with different discharge conditions, we could distinguish between different elements and between different degrees of ionization of Ho. Altogether 2862 lines could be assigned to atomic Ho, 2417 of which had not been listed in literature up to now. Based on the known energy levels of atomic holmium, 987 lines have been classified, 627 of which have been classified for the first time.
Line Identification of Atomic and Ionic Spectra of Holmium in the Visible Spectral Range. II. Spectrum of Ho ii and Ho iii
Authors: Özdalgiç B. , Başar Gö. , Güzelçimen F. , Öztürk I. K. , Ak T. , Bilir S. , Tamanis M. , Ferber R. , Kröger S.
Published: February 2019

Fourier Transform spectra of Holmium (Ho) in the visible spectral range from 14,280 up to 25,000 cm−1, or 400 to 700 nm have been investigated, with a focus on the ionic lines. More than 500 spectral lines were assigned to singly ionized Ho (Ho ii), of which more than 400 were previously unknown. A further 21 lines were assigned to doubly ionized Ho (Ho iii), 1 of which was not reported previously. From among these lines, 60 Ho ii lines and 20 Ho iii lines were classified. A complete list of more than 4000 Ho lines observed in the recorded spectrum is supplied, even if they remain unclassified.
Atherosclerotic Vascular Events in Systemic Lupus Erythematosus: An Evolving Story
Authors: Urowitz Murray B. , Su Jiandong , Gladman Dafna D.
Published: February 2019

Objective.

Atherosclerotic vascular events (AVE) are a major cause of mortality and morbidity in systemic lupus erythematosus (SLE). We aimed to determine the effect of early recognition and therapy for both classic risk factors for AVE and for SLE, on the burden of AVE in SLE in recent decades.

Methods.

Inception patients who entered the University of Toronto Lupus Clinic between 1975 and 1987 followed to 1992 (Cohort 1), and between 1999 and 2011 followed to 2016 (Cohort 2) were studied. AVE attributed to atherosclerosis and occurring during the 17 years were identified. SLE disease activity and therapy as well as hypertension, hypercholesterolemia, hyperglycemia, and smoking were assessed. Analysis included descriptive statistics on baseline characteristics, traditional risk factors over the followup, outcome rates by each 100 person-years (PY), Kaplan-Meier cumulative AVE curves, as well as competing risk Cox models adjusted by inverse probability weights.

Results.

Of the 234 patients in Cohort 1, 26 patients (11%) had an AVE compared with 10 of 262 patients (3.8%) in Cohort 2. The rate per 100 PY of followup was 1.8 in Cohort 1 and 0.44 in Cohort 2 (p < 0.0001). Better control of all risk factors and disease activity was achieved in Cohort 2. There was a reduction of 60% in the risk for AVE in Cohort 2.

Conclusion.

The incidence of AVE in SLE in the modern era has declined in large part owing to more effective management of classic coronary artery risk factors and of SLE.
OMERACT Development of a Core Domain Set of Outcomes for Shared Decision-making Interventions
Authors: Toupin-April Karine , Barton Jennifer L. , Fraenkel Liana , Meara Alexa , Li Linda C. , Brooks Peter , de Wit Maarten , Stacey Dawn , Légaré France , Shea Beverley , Lyddiatt Anne , Hofstetter Cathie , Christensen Robin , Scholte Voshaar Marieke , Suarez-Almazor Maria E. , Boonen Annelies , Meade Tanya , March Lyn , Jull Janet Elizabeth , Campbell Willemina , Alten Rieke , Karuranga Suvi , Morgan Esi M. , Kelly Ayano , Kaufman Jessica , Hill Sophie , Maxwell Lara J. , Beaton Dorcas , El-Miedany Yasser , Mittoo Shikha , Bartlett Susan J. , Singh Jasvinder A. , Tugwell Peter S.
Published: February 2019

Objective.

The Outcome Measures in Rheumatology (OMERACT) Shared Decision Making (SDM) Working Group aims to determine the core outcome domain set for measuring the effectiveness of SDM interventions in rheumatology trials.

Methods.

A white paper was developed to clarify the draft core domain set. It was then used to prepare for interviews to investigate reasons for lack of consensus on it and to suggest further improvements.

Results.

OMERACT scientists/clinicians (n = 13) and patients (n = 10) suggested limiting the core domain set to outcome domains, removing process domains, and clarifying remaining domains.

Conclusion.

A revised core domain set will undergo further consensus-building.
Comment décider et prospérer dans un monde de surprises ?
Authors: Silberzahn Philippe
Published: February 2019

Selon Philippe Silberzahn, la figure de l’entrepreneur visionnaire et agile ainsi que celle du décideur soucieux de prévisions rationnelles sont des leurres. L’avenir ne peut être maîtrisé, mais pour l’apprivoiser, on peut tirer parti des surprises et contingences, nombreuses dans un monde complexe.