bluuebunny/crossref_metadata_2025 huggingface dataset:
Reactive Pad-Steam Dyeing of Cotton Fabric Modified with Cationic P(St-BA-VBT) Nanospheres
Authors: Fang Kuanjun , Shu Dawu , Liu Xiuming , Cai Yuqing , An Fangfang , Zhang Xinqing
Published: May 2018

The Poly[Styrene-Butyl acrylate-(P-vinylbenzyl trimethyl ammonium chloride)] P(St-BA-VBT) nanospheres with N+(CH3)3 functional groups were successfully prepared and applied to modify cotton fabrics using a pad-dry process. The obtained cationic cotton fabrics were dyed with pad-steam dyeing with reactive dye. The results show that the appropriate concentration of nanospheres was 4 g/L. The sodium carbonate of 25 g/L and steaming time of 3 min were suitable for dyeing cationic cotton with 25 g/L of C.I. Reactive Blue 222. The color strength and dye fixation rates of dyed cationic cotton fabrics increased by 39.4% and 14.3% compared with untreated fabrics. Moreover, sodium carbonate and steaming time were reduced by 37.5% and 40%, respectively. The rubbing and washing fastness of dyed fabrics were equal or higher 3 and 4–5 grades, respectively. Scanning electron microscopy (SEM) images revealed that the P(St-BA-VBT) nanospheres randomly distributed and did not form a continuous film on the cationic cotton fiber surfaces. The X-ray photoelectron spectroscopy (XPS) analysis further demonstrated the presence of cationic nanospheres on the fiber surfaces. The cationic modification did not affect the breaking strength of cotton fabrics.
The Manipulation of Social, Cultural and Religious Values in Socially Mediated Terrorism
Authors: Smith Claire , Von der Borch Rosslyn , Isakhan Benjamin , Sukendar Sukendar , Sulistiyanto Priyambudi , Ravenscrroft Ian , Widianingsih Ida , De Leiuen Cherrie
Published: May 2018

This paper presents an analysis of how the Islamic State/Da’esh and Hizb ut-Tahrir Indonesia manipulate conflicting social, cultural and religious values as part of their socially mediated terrorism. It focusses on three case studies: (1) the attacks in Paris, France on 13 November 2015; (2) the destruction of cultural heritage sites in Iraq and Syria; and (3) the struggle between nationalist values and extreme Islamic values in Indonesia. The case studies were chosen as a basis for identifying global commonalities as well as regional differences in socially mediated terrorism. They are located in Asia, the Middle East and Europe. The integrated analysis of these case studies identifies significant trends and suggests actions that could lessen the impact of strategies deployed by extremist groups such as Da’esh, al-Qaeda and Hizb ut-Tahrir. We discuss the broader implications for understanding various aspects of socially mediated terrorism.
Performance Assessment of the COMET Cloud Fractional Cover Climatology across Meteosat Generations
Authors: Bojanowski Jędrzej S. , Stöckli Reto , Duguay-Tetzlaff Anke , Finkensieper Stephan , Hollmann Rainer
Published: May 2018

The CM SAF Cloud Fractional Cover dataset from Meteosat First and Second Generation (COMET, https://doi.org/10.5676/EUM_SAF_CM/CFC_METEOSAT/V001) covering 1991–2015 has been recently released by the EUMETSAT Satellite Application Facility for Climate Monitoring (CM SAF). COMET is derived from the MVIRI and SEVIRI imagers aboard geostationary Meteosat satellites and features a Cloud Fractional Cover (CFC) climatology in high temporal (1 h) and spatial (0.05° × 0.05°) resolution. The CM SAF long-term cloud fraction climatology is a unique long-term dataset that resolves the diurnal cycle of cloudiness. The cloud detection algorithm optimally exploits the limited information from only two channels (broad band visible and thermal infrared) acquired by older geostationary sensors. The underlying algorithm employs a cyclic generation of clear sky background fields, uses continuous cloud scores and runs a naïve Bayesian cloud fraction estimation using concurrent information on cloud state and variability. The algorithm depends on well-characterized infrared radiances (IR) and visible reflectances (VIS) from the Meteosat Fundamental Climate Data Record (FCDR) provided by EUMETSAT. The evaluation of both Level-2 (instantaneous) and Level-3 (daily and monthly means) cloud fractional cover (CFC) has been performed using two reference datasets: ground-based cloud observations (SYNOP) and retrievals from an active satellite instrument (CALIPSO/CALIOP). Intercomparisons have employed concurrent state-of-the-art satellite-based datasets derived from geostationary and polar orbiting passive visible and infrared imaging sensors (MODIS, CLARA-A2, CLAAS-2, PATMOS-x and CC4CL-AVHRR). Averaged over all reference SYNOP sites on the monthly time scale, COMET CFC reveals (for 0–100% CFC) a mean bias of −0.14%, a root mean square error of 7.04% and a trend in bias of −0.94% per decade. The COMET shortcomings include larger negative bias during the Northern Hemispheric winter, lower precision for high sun zenith angles and high viewing angles, as well as an inhomogeneity around 1995/1996. Yet, we conclude that the COMET CFC corresponds well to the corresponding SYNOP measurements, and it is thus useful to extend in both space and time century-long ground-based climate observations.
Random Forest Variable Importance Spectral Indices Scheme for Burnt Forest Recovery Monitoring—Multilevel RF-VIMP
Authors: Boonprong Sornkitja , Cao Chunxiang , Chen Wei , Bao Shanning
Published: May 2018

Burnt forest recovery is normally monitored with a time-series analysis of satellite data because of its proficiency for large observation areas. Traditional methods, such as linear correlation plotting, have been proven to be effective, as forest recovery naturally increases with time. However, these methods are complicated and time consuming when increasing the number of observed parameters. In this work, we present a random forest variable importance (RF-VIMP) scheme called multilevel RF-VIMP to compare and assess the relationship between 36 spectral indices (parameters) of burnt boreal forest recovery in the Great Xing’an Mountain, China. Six Landsat images were acquired in the same month 0, 1, 4, 14, 16, and 20 years after a fire, and 39,380 fixed-location samples were then extracted to calculate the effectiveness of the 36 parameters. Consequently, the proposed method was applied to find correlations between the forest recovery indices. The experiment showed that the proposed method is suitable for explaining the efficacy of those spectral indices in terms of discrimination and trend analysis, and for showing the satellite data and forest succession dynamics when applied in a time series. The results suggest that the tasseled cap transformation wetness, brightness, and the shortwave infrared bands (both 1 and 2) perform better than other indices for both classification and monitoring.
Suspended Carbon Nanotubes for Humidity Sensing
Authors: Arunachalam Shivaram , Gupta Anubha A. , Izquierdo Ricardo , Nabki Frederic
Published: May 2018

A room temperature microfabrication technique using SU8, an epoxy-based highly functional photoresist as a sacrificial layer, is developed to obtain suspended aligned carbon nanotube beams. The humidity-sensing characteristics of aligned suspended single-walled carbon nanotube films are studied. A comparative study between suspended and non-suspended architectures is done by recording the resistance change in the nanotubes under humidity. For the tests, the humidity was varied from 15% to 98% RH. A comparative study between suspended and non-suspended devices shows that the response and recovery times of the suspended devices was found to be almost 3 times shorter than the non-suspended devices. The suspended devices also showed minimal hysteresis even after 10 humidity cycles, and also exhibit enhanced sensitivity. Repeatability tests were performed by subjecting the sensors to continuous humidification cycles. All tests reported here have been performed using pristine non-functionalized nanotubes.
Automated Field-of-View, Illumination, and Recognition Algorithm Design of a Vision System for Pick-and-Place Considering Colour Information in Illumination and Images
Authors: Chen Yibing , Ogata Taiki , Ueyama Tsuyoshi , Takada Toshiyuki , Ota Jun
Published: May 2018

Machine vision is playing an increasingly important role in industrial applications, and the automated design of image recognition systems has been a subject of intense research. This study has proposed a system for automatically designing the field-of-view (FOV) of a camera, the illumination strength and the parameters in a recognition algorithm. We formulated the design problem as an optimisation problem and used an experiment based on a hierarchical algorithm to solve it. The evaluation experiments using translucent plastics objects showed that the use of the proposed system resulted in an effective solution with a wide FOV, recognition of all objects and 0.32 mm and 0.4° maximal positional and angular errors when all the RGB (red, green and blue) for illumination and R channel image for recognition were used. Though all the RGB illumination and grey scale images also provided recognition of all the objects, only a narrow FOV was selected. Moreover, full recognition was not achieved by using only G illumination and a grey-scale image. The results showed that the proposed method can automatically design the FOV, illumination and parameters in the recognition algorithm and that tuning all the RGB illumination is desirable even when single-channel or grey-scale images are used for recognition.
A Nonlinear Calibration Algorithm Based on Harmonic Decomposition for Two-Axis Fluxgate Sensors
Authors: Feng Wenguang , Liu Shibin
Published: May 2018

Nonlinearity is a prominent limitation to the calibration performance for two-axis fluxgate sensors. In this paper, a novel nonlinear calibration algorithm taking into account the nonlinearity of errors is proposed. In order to establish the nonlinear calibration model, the combined effort of all time-invariant errors is analyzed in detail, and then harmonic decomposition method is utilized to estimate the compensation coefficients. Meanwhile, the proposed nonlinear calibration algorithm is validated and compared with a classical calibration algorithm by experiments. The experimental results show that, after the nonlinear calibration, the maximum deviation of magnetic field magnitude is decreased from 1302 nT to 30 nT, which is smaller than 81 nT after the classical calibration. Furthermore, for the two-axis fluxgate sensor used as magnetic compass, the maximum error of heading is corrected from 1.86° to 0.07°, which is approximately 11% in contrast with 0.62° after the classical calibration. The results suggest an effective way to improve the calibration performance of two-axis fluxgate sensors.
An Identity-Based Anti-Quantum Privacy-Preserving Blind Authentication in Wireless Sensor Networks
Authors: Zhu Hongfei , Tan Yu-an , Zhu Liehuang , Wang Xianmin , Zhang Quanxin , Li Yuanzhang
Published: May 2018

With the development of wireless sensor networks, IoT devices are crucial for the Smart City; these devices change people’s lives such as e-payment and e-voting systems. However, in these two systems, the state-of-art authentication protocols based on traditional number theory cannot defeat a quantum computer attack. In order to protect user privacy and guarantee trustworthy of big data, we propose a new identity-based blind signature scheme based on number theorem research unit lattice, this scheme mainly uses a rejection sampling theorem instead of constructing a trapdoor. Meanwhile, this scheme does not depend on complex public key infrastructure and can resist quantum computer attack. Then we design an e-payment protocol using the proposed scheme. Furthermore, we prove our scheme is secure in the random oracle, and satisfies confidentiality, integrity, and non-repudiation. Finally, we demonstrate that the proposed scheme outperforms the other traditional existing identity-based blind signature schemes in signing speed and verification speed, outperforms the other lattice-based blind signature in signing speed, verification speed, and signing secret key size.
Wave Propagation in Aluminum Honeycomb Plate and Debonding Detection Using Scanning Laser Vibrometer
Authors: Zhao Jingjing , Li Fucai , Cao Xiao , Li Hongguang
Published: May 2018

Both the aerospace and marine industry have widely relied on a honeycomb sandwich structure (HSS) because of its high strength-to-weight ratio. However, the intrinsic nature of an adhesively bonded multi-layer structure increases the risk of debonding when the structure is under strain or exposed to varying temperatures. Such defects are normally concealed under the surface but can significantly compromise the strength and stiffness of a structure. In this paper, the guided wave method is used to detect debondings which are located between the skin and the honeycomb in sandwich plates. The propagation of guided waves in honeycomb plates is investigated via numerical techniques, with emphasis placed on demonstrating the behavior of structure-based wave interactions (SWIs). The SWI technique is effective to distinguish heterogeneous structures from homogeneous structures. The excitation frequency is necessary to generate obvious SWIs in HSSs; accordingly, a novel strategy is proposed to select the optimal excitation frequencies. A series of experiments are conducted, the results of which show that the presented procedure can be used to effectively detect the locations and the sizes of single- and multi-damage zones in HSSs.
A Tool for Sourcing Sustainable Building Renovation: The Energy Efficiency Maturity Matrix
Authors: Stenqvist Christian , Nielsen Susanne Balslev , Bengtsson Per-Otto
Published: May 2018

The success of sustainable building renovation is inevitably dependent on the capabilities of the involved stakeholders throughout the entire project. Therefore, any building client with intentions of sustainable building renovations must reflect on sourcing the adequate capabilities for a sustainable renovation project. The question in focus is: how to facilitate a sourcing strategy for energy-efficient sustainable building renovation and maintenance. This study on energy efficiency implementations shows that even in developed countries like Sweden, where energy efficiency is regulated by the EU, national legislation and other public policies, the municipal facilities management organizations need process guidance to navigate in decisions regarding in-house capabilities and collaboration with external service providers. A dialogue tool for the sourcing process, the energy efficiency maturity matrix, is developed to support future sourcing processes for energy-efficient buildings as a prominent part of the broader field of sustainable building renovation and maintenance. The future will show when building clients to a larger extent will embrace sourcing strategies instead of mainly focusing on specific technical improvements. The new International standards for facilities management (ISO18480 series) might support this change process, as it includes a sourcing approach, from a strategic level to an operational level, to add more value and to optimize costs.
Influence Factors and Regression Model of Urban Housing Prices Based on Internet Open Access Data
Authors: Wu Hao , Jiao Hongzan , Yu Yang , Li Zhigang , Peng Zhenghong , Liu Lingbo , Zeng Zheng
Published: May 2018

With the commercialization of housing and the deepening of urbanization in China, housing prices are having increasing influence on the land market, and thus indirectly affecting urban development. As various spatial features of an urban housing property directly affect its price, the study of this connection has significance for urban planning. The present study uses mainly open internet data of housing prices, supplemented by other data sources, to identify the spatial features of housing prices and the influence factors in a case study city, Wuhan. Methods employed in the study include the hedonic linear regression model, the geographically weighted regression (GWR) model and the artificial neural network (ANN) model, etc. Progress is made in the following two aspects: first, when calculating the influence factors, hierarchical values for accessibility variables of certain public facilities are used instead of simple Euclidean distance and the results shows a better model fit; second, the ANN model shows the best fit in the study, and while the three models all show respective strengths, the combined use of all models offers the possibility of a more comprehensive analysis of the influence factors of housing prices.
A Multi-Temporal Analyses of Land Surface Temperature Using Landsat-8 Data and Open Source Software: The Case Study of Modena, Italy
Authors: Barbieri Tommaso , Despini Francesca , Teggi Sergio
Published: May 2018

The Urban Heat Island (UHI) phenomenon, namely urban areas where the atmospheric temperature is significantly higher than in the surrounding rural areas, is currently a very well-known topic both in the scientific community and in public debates. Growing urbanization is one of the anthropic causes of UHI. The UHI phenomenon has a negative impact on the life quality of the local population (thermal discomfort, summer thermal shock, etc.), thus investigations and analyses on this topic are really useful and important for correct and sustainable urban planning; this study is included in this context. A multi-temporal analysis was performed in the municipality of Modena (Italy) to identify and estimate the Surface Urban Heat Island (SUHI, strictly correlated to the UHI phenomenon) from 2014 to 2017. For this purpose, Landsat-8 satellite images were processed with Quantum Geographic Information System (QGIS) to obtain the Land Surface Temperature (LST) and the Normalized Difference Vegetation Index (NDVI). For every pixel, LST and NDVI values of three regions of interest (ROI, i.e., Countryside, Suburbs, and City Center) were extracted and their correlations were investigated. A maximum variation of 6.4 °C in the LST values between City Center and Countryside was highlighted, confirming the presence of the SUHI phenomenon even in a medium-sized municipality like Modena. The implemented procedure demonstrates that satellite data are suitable for SUHI identification and estimation, therefore it could be a useful tool for public administration for urban planning policies.
Balancing Urban Biodiversity Needs and Resident Preferences for Vacant Lot Management
Authors: Rega-Brodsky Christine C. , Nilon Charles H. , Warren Paige S.
Published: May 2018

Urban vacant lots are often a contentious feature in cities, seen as overgrown, messy eyesores that plague neighborhoods. We propose a shift in this perception to locations of urban potential, because vacant lots may serve as informal greenspaces that maximize urban biodiversity while satisfying residents’ preferences for their design and use. Our goal was to assess what kind of vacant lots are ecologically valuable by assessing their biotic contents and residents’ preferences within a variety of settings. We surveyed 150 vacant lots throughout Baltimore, Maryland for their plant and bird communities, classified the lot’s setting within the urban matrix, and surveyed residents. Remnant vacant lots had greater vegetative structure and bird species richness as compared to other lot origins, while vacant lot settings had limited effects on their contents. Residents preferred well-maintained lots with more trees and less artificial cover, support of which may increase local biodiversity in vacant lots. Collectively, we propose that vacant lots with a mixture of remnant and planted vegetation can act as sustainable urban greenspaces with the potential for some locations to enhance urban tree cover and bird habitat, while balancing the needs and preferences of city residents.
Analysis of Environmental Carrying Capacity with Emergy Perspective of Jeju Island
Authors: Jung Chanhoon , Kim Chanwoo , Kim Solhee , Suh Kyo
Published: May 2018

Jeju Island experienced an approximately 42% increase in energy consumption from 2006 to 2015 and the demand for energy consumption is expected to continue to increase. Thus, Jeju Island is planning a project entitled “Carbon Free Island by 2030” to promote sustainable development and is required to estimate the environmental carrying capacity for future energy demand changes. The purpose of this study was to calculate the emergy inherent in Jeju Island’s energy, materials, and information in 2015 using the emergy analysis method and local characteristics. In addition, this study aimed to estimate the emergy indices to evaluate the environmental carrying capacity for sustainable development in 2005, 2015, and 2030 considering the future energy demand. This study’s outputs provide the environmental carrying capacity with emergy indices, such as the percent renewable (%Renew), emergy yield ratio (EYR), environmental loading ratio (ELR), sustainability index (SI), and carrying capacity of the population (CCP) for social and economic activities on Jeju Island, which are expected to be saturated. These findings show regions with heavy tourism require development strategies, including the concept of environmental carrying capacity.
Building Ownership, Renovation Investments, and Energy Performance—A Study of Multi-Family Dwellings in Gothenburg
Authors: Mangold Mikael , Österbring Magnus , Overland Conny , Johansson Tim , Wallbaum Holger
Published: May 2018

The European building stock was renewed at a rapid pace during the period 1950–1975. In many European countries, the building stock from this time needs to be renovated, and there are opportunities to introduce energy efficiency measures in the renovation process. Information availability and increasingly available analysis tools make it possible to assess the impact of policy and regulation. This article describes methods developed for analyzing investments in renovation and energy performance based on building ownership and inhabitant socio-economic information developed for Swedish authorities, to be used for the Swedish national renovations strategy in 2019. This was done by analyzing measured energy usage and renovation investments made during the last 30 years, coupled with building specific official information of buildings and resident area characteristics, for multi-family dwellings in Gothenburg (N = 6319). The statistical analyses show that more costly renovations lead to decreasing energy usage for heating, but buildings that have been renovated during the last decades have a higher energy usage when accounting for current heating system, ownership, and resident socio-economic background. It is appropriate to include an affordability aspect in larger renovation projects since economically disadvantaged groups are over-represented in buildings with poorer energy performance.
Decision and Coordination in a Low-Carbon E-Supply Chain Considering the Manufacturer’s Carbon Emission Reduction Behavior
Authors: Han Qiang , Wang Yuyan
Published: May 2018

At present, online shopping is becoming increasingly popular. In particular, low-carbon products are becoming more favored as consumers’ low-carbon awareness increases. Manufacturers sell their low-carbon products through e-commerce platforms. Thus, the manufacturer and the e-commerce platform form a low-carbon e-supply chain system. The manufacturer makes products with carbon emission reduction efforts, while the e-commerce platform provides a sales service. In this paper, we described models for a decentralized decision mode and a centralized decision mode in the low-carbon e-supply chain, and compare the decision results. Our findings show that the centralized decision mode has a better performance than the decentralized one, the ability of the e-supply chain to respond to consumers’ preference for a low-carbon product has a direct effect on its operation, and the manufacturer’s carbon emission reduction behavior will be a potential source for enterprises to gain more revenue. Further, we designed a coordination contract for them that can be accepted by both sides in the decentralized decision mode. We find that if the e-commerce platform can share the carbon emission reduction costs of the manufacturer, the performance of the e-supply chain will be greatly improved. A practical case study and numerical examples validate our analysis.
Optimizing Regional Food and Energy Production under Limited Water Availability through Integrated Modeling
Authors: Gao Junlian , Xu Xiangyang , Cao Guiying , Ermoliev Yurii M. , Ermolieva Tatiana Y. , Rovenskaya Elena A.
Published: May 2018

Across the world, human activity is approaching planetary boundaries. In northwest China, in particular, the coal industry and agriculture are competing for key limited inputs of land and water. In this situation, the traditional approach to planning the development of each sector independently fails to deliver sustainable solutions, as solutions made in sectorial ‘silos’ are often suboptimal for the entire economy. We propose a spatially detailed cost-minimizing model for coal and agricultural production in a region under constraints on land and water availability. We apply the model to the case study of Shanxi province, China. We show how such an integrated optimization, which takes maximum advantage of the spatial heterogeneity in resource abundance, could help resolve the conflicts around the water–food–energy (WFE) nexus and assist in its management. We quantify the production-possibility frontiers under different water-availability scenarios and demonstrate that in water-scarce regions, like Shanxi, the production capacity and corresponding production solutions are highly sensitive to water constraints. The shadow prices estimated in the model could be the basis for intelligent differentiated water pricing, not only to enable the water-resource transfer between agriculture and the coal industry, and across regions, but also to achieve cost-effective WFE management.
The Effectiveness of Government Subsidies on Manufacturing Innovation: Evidence from the New Energy Vehicle Industry in China
Authors: Jiang Cailou , Zhang Ying , Bu Maoliang , Liu Weishu
Published: May 2018

Manufacturing innovation is of strategic importance to China in its effort to reshape future technology. This study explores the impact of government subsidies on the research and development (R&D) intensity of China’s new energy vehicle (NEV) enterprises. The dynamic relationship between government subsidies and R&D intensity is tested with a panel regression model and a threshold regression model. We find that government subsidies have a significantly positive impact on R&D intensity when considering the sample group as a whole, but market profit does not contribute to R&D intensity. As for the sub-sample, government subsidies have a significantly positive impact on R&D intensity in assembly enterprises but are insignificant in supporting enterprises. Two threshold values are also identified with the logarithm of government subsidy. We find that government subsidies have a significant crowding in effect on the R&D intensity of NEV enterprises. With the increasing of government subsidy, the crowding in effect weakens gradually. The policy implication is that the structure of government subsidies should be optimized. More demand-oriented policy instruments should be adopted to cultivate the market. The government subsidies should be reduced gradually until full withdrawal.
Alaska Snowpack Response to Climate Change: Statewide Snowfall Equivalent and Snowpack Water Scenarios
Authors: Littell Jeremy S. , McAfee Stephanie A. , Hayward Gregory D.
Published: May 2018

Climatically driven changes in snow characteristics (snowfall, snowpack, and snowmelt) will affect hydrologic and ecological systems in Alaska over the coming century, yet there exist no projections of downscaled future snow pack metrics for the state of Alaska. We updated historical and projected snow day fraction (PSF, the fraction of days with precipitation falling as snow) from McAfee et al. We developed modeled snowfall equivalent (SFE) derived from the product of snow-day fraction (PSF) and existing gridded precipitation for Alaska from Scenarios Network for Alaska and Arctic Planning (SNAP). We validated the assumption that modeled SFE approximates historical decadally averaged snow water equivalent (SWE) observations from snowcourse and Snow Telemetry (SNOTEL) sites. We present analyses of future downscaled PSF and two new products, October–March SFE and ratio of snow fall equivalent to precipitation (SFE:P) based on bias-corrected statistically downscaled projections of Coupled Model Intercomparison Project 5 (CMIP5) Global Climate Model (GCM) temperature and precipitation for the state of Alaska. We analyzed mid-century (2040–2069) and late-century (2070–2099) changes in PSF, SFE, and SFE:P relative to historical (1970–1999) mean temperature and present results for Alaska climate divisions and 12-digit Hydrologic Unit Code (HUC12) watersheds. Overall, estimated historical the SFE is reasonably well related to the observed SWE, with correlations over 0.75 in all decades, and correlations exceeding 0.9 in the 1960s and 1970s. In absolute terms, SFE is generally biased low compared to the observed SWE. PSF and SFE:P decrease universally across Alaska under both Representative Concentration Pathway (RCP) 4.5 and RCP 8.5 emissions scenarios, with the smallest changes for RCP 4.5 in 2040–2069 and the largest for RCP 8.5 in 2070–2099. The timing and magnitude of maximum decreases in PSF vary considerably with regional average temperature, with the largest changes in months at the beginning and end of the snow season. Mean SFE changes vary widely among climate divisions, ranging from decreases between −17 and −58% for late twenty-first century in southeast, southcentral, west coast and southwest Alaska to increases up to 21% on the North Slope. SFE increases most at highest elevations and latitudes and decreases most in coastal southern Alaska. SFE:P ratios indicate a broad switch from snow-dominated to transitional annual hydrology across most of southern Alaska by mid-century, and from transitional to rain-dominated watersheds in low elevation parts of southeast Alaska by the late twenty-first century.
The Next Generation Fornax Survey (NGFS). III. Revealing the Spatial Substructure of the Dwarf Galaxy Population Inside Half of Fornax's Virial Radius
Authors: Ordenes-Briceño Yasna , Eigenthaler Paul , Taylor Matthew A. , Puzia Thomas H. , Alamo-Martínez Karla , Ribbeck Karen X. , P. Muñoz Roberto , Zhang Hongxin , Grebel Eva K. , Ángel Simón , Côté Patrick , Ferrarese Laura , Hilker Michael , Lançon Ariane , Mieske Steffen , Miller Bryan W. , Rong Yu , Sánchez-Janssen Ruben
Published: May 2018

We report the discovery of 271 previously undetected dwarf galaxies in the outer Fornax cluster regions at radii r
vir/4 < r < r
vir/2 using data from the Next Generation Fornax Survey (NGFS) with deep coadded u′, g′, and i′ images obtained with Blanco/DECam at Cerro Tololo Interamerican Observatory. From the 271 dwarf candidates, we find 39 to be nucleated. Together with our previous study of the central Fornax region, the new dwarfs detected with NGFS data number 392, of which 56 are nucleated. The total Fornax dwarf galaxy population from NGFS and other catalogs rises, therefore, to a total of 643 with 181 being nucleated, yielding an overall nucleation fraction of 28%. The absolute i′-band magnitudes for the outer NGFS dwarfs are in the range −18.80 ≤  M

i′ ≤  −8.78 with effective radii r
eff,i′ = 0.18–2.22 kpc and an average Sérsic index

. Nonnucleated dwarfs are found to be fainter and smaller by

mag and

than the nucleated dwarfs. We demonstrate a significant clustering of dwarf galaxies on scales ≲100 kpc, and projected surface number density profile estimates, Σ
N
(r), show a concentration of dwarfs in the Fornax core region within r ≲ 350 kpc. Σ
N
(r) has a flat distribution up to ∼350 kpc, beyond which it declines for the nonnucleated dwarfs. The nucleated dwarfs have a steeper Σ
N
(r) distribution, are more concentrated toward NGC 1399, and are decreasing rapidly outwards. This is the first time the transition from cluster to field environment has been established for the very faint dwarf galaxy population with robust sample statistics.
Hot Cores in Magellanic Clouds
Authors: Acharyya Kinsuk , Herbst Eric
Published: May 2018

We have studied the chemistry of molecules through complex organic molecules (COMs) in complexity in conditions resembling galactic hot molecular cores in the Large and Small Magellanic Clouds using a gas-grain network. To the best of our knowledge, there have been no previous such quantitative studies of hot core chemistry in these low metallicity, dust-poor galaxies. We utilized a physical model that consists of an initial isothermal collapse, followed by a warm-up phase to hot core conditions. Four different temperatures—10, 15, 20, and 25 K—were used for the isothermal collapse phase, considering the fact that these galaxies might have higher dust temperatures in cold regions than observed in the Milky Way. We found that for some abundant species, such as CO and water, hot core abundances are consistent with the reduced elemental abundances of the LMC and SMC. For other less abundant species, such as CH4 and HCN, the calculated abundances are larger when compared with elemental abundances, whereas for species like ammonia they are lower. Our calculations show that some COMs can also be formed in reasonable quantity for hot cores in the Magellanic Clouds when the grain temperature is lower than 25 K. Our results can be compared with recent observations of the hot cores in the high-mass young stellar object (YSO) ST11 and regions A1 and B3 of the star-forming source N113 in the LMC. Model results are in reasonable agreement with the observed abundances and upper limits.
Microlensing and Intrinsic Variability of the Broad Emission Lines of Lensed Quasars
Authors: Fian C. , Guerras Eduardo , Mediavilla E. , Jiménez-Vicente J. , Muñoz J. A. , Falco E. E. , Motta V. , Hanslmeier A.
Published: May 2018

We study the broad emission lines in a sample of 11 gravitationally lensed quasars with at least two epochs of observation to identify intrinsic variability and to disentangle it from microlensing. To improve our statistical significance and emphasize trends, we also include 15 lens systems with single-epoch spectra. Mg ii and C iii] emission lines are only weakly affected by microlensing, but C iv shows strong microlensing in some cases, even for regions of the line core, presumably associated with small projected velocities. However, excluding the strongly microlensed cases, there is a strikingly good match, on average, between the red wings of the C iv and C iii] profiles. Analysis of these results supports the existence of two regions in the broad-line region (BLR), one that is insensitive to microlensing (of size ≳50 lt-day and kinematics not confined to a plane) and another that shows up only when it is magnified by microlensing (of size of a few light-days, comparable to the accretion disk). Both regions can contribute in different proportions to the emission lines of different species and, within each line profile, to different velocity bins, all of which complicates detailed studies of the BLR based on microlensing size estimates. The strength of the microlensing indicates that some spectral features that make up the pseudo-continuum, such as the shelf-like feature at λ1610 or several Fe iii blends, may in part arise from an inner region of the accretion disk. In the case of Fe ii, microlensing is strong in some blends but not in others. This opens up interesting possibilities to study quasar accretion disk kinematics. Intrinsic variability seems to affect the same features prone to microlensing, with similar frequency and amplitude, but does not induce outstanding profile asymmetries. We measure intrinsic variability (≲20%) of the wings with respect to the cores in the C iv, C iii], and Mg ii lines consistent with reverberation mapping studies.
X-Ray Flux and Spectral Variability of Six TeV Blazars with NuSTAR
Authors: Pandey Ashwani , Gupta Alok C. , Wiita Paul J.
Published: May 2018

We report the first results of timing and spectral studies of Nuclear Spectroscopic Telescope Array observations of six TeV-emitting high-frequency peaked blazars: 1ES 0347-121, 1ES 0414+009, RGB J0710+591, 1ES 1101-232, 1ES 1218+304, and H 2356-309. Two out of these six TeV blazars, 1ES 1101−232 and 1ES 1218+304, showed strong evidence of intraday variations in the 3–79 keV energy range during those observations. We also found a hint of an intraday variability timescale of 23.5 ks in the light curve of 1ES 1218+304 using an autocorrelation function analysis. We obtained a magnetic field B ∼ 0.03 G, electron Lorentz factor γ ∼ 2.16 × 106, and emission region size R ∼ 1.19 × 1016 cm for 1ES 1218+304 using that variability timescale. The other blazars’ light curves do not show any variability timescales shorter than their observation lengths; however, we note that the data were both noisier and sparser for them. We also investigated the spectral shape of these TeV blazars and found that the spectrum of 1ES 0414+009 is well described by a single power law with a photon index Γ ∼ 2.77. The spectra of the other five HBLs are somewhat better represented by log-parabola models with local photon indices (at 10 keV) α ∼ 2.23 − 2.67 and curvature parameters β ∼ 0.27 − 0.43.
Ultra-long Gamma-Ray Bursts from the Collapse of Blue Supergiant Stars: An End-to-end Simulation
Authors: Perna Rosalba , Lazzati Davide , Cantiello Matteo
Published: May 2018

Ultra-long gamma-ray bursts (ULGRBs) are a distinct class of GRBs characterized by durations of several thousands of seconds, about two orders of magnitude longer than those of standard long GRBs (LGRBs). The driving engine of these events has not yet been uncovered, and ideas range from magnetars, to tidal disruption events, to extended massive stars, such as blue super giants (BSG). BSGs, a possible endpoint of stellar evolution, are attractive for the relatively long freefall times of their envelopes, allowing accretion to power a long-lasting central engine. At the same time, their large radial extension poses a challenge to the emergence of a jet. Here, we perform an end-to-end simulation aimed at assessing the viability of BSGs as ULGRB progenitors. The evolution to the core-collapse of a BSG star model is calculated with the MESA code. We then compute the accretion rate for the fraction of envelope material with enough angular momentum to circularize and form an accretion disk, and input the corresponding power into a jet, which we evolve through the star envelope with the FLASH code. Our simulation shows that the jet can emerge, and the resulting light curves resemble those observed in ULGRBs, with durations T
90 ranging from ≈4000 s to ≈104 s, depending on the viewing angle.
Peering into the Dark Side: Magnesium Lines Establish a Massive Neutron Star in PSR J2215+5135
Authors: Linares M. , Shahbaz T. , Casares J.
Published: May 2018

New millisecond pulsars (MSPs) in compact binaries provide a good opportunity to search for the most massive neutron stars. Their main-sequence companion stars are often strongly irradiated by the pulsar, displacing the effective center of light from their barycenter and making mass measurements uncertain. We present a series of optical spectroscopic and photometric observations of PSR J2215+5135, a “redback” binary MSP in a 4.14 hr orbit, and measure a drastic temperature contrast between the dark/cold (T
N = 5660

K) and bright/hot (T
D = 8080

K) sides of the companion star. We find that the radial velocities depend systematically on the atmospheric absorption lines used to measure them. Namely, the semi-amplitude of the radial velocity curve (RVC) of J2215 measured with magnesium triplet lines is systematically higher than that measured with hydrogen Balmer lines, by 10%. We interpret this as a consequence of strong irradiation, whereby metallic lines dominate the dark side of the companion (which moves faster) and Balmer lines trace its bright (slower) side. Further, using a physical model of an irradiated star to fit simultaneously the two-species RVCs and the three-band light curves, we find a center-of-mass velocity of K
2 = 412.3 ± 5.0 km s−1 and an orbital inclination i = 63.°9

. Our model is able to reproduce the observed fluxes and velocities without invoking irradiation by an extended source. We measure masses of M
1 = 2.27

 M
⊙ and M
2 = 0.33

 M
⊙ for the neutron star and the companion star, respectively. If confirmed, such a massive pulsar would rule out some of the proposed equations of state for the neutron star interior.
A Circumbinary Disk Model for the Rapid Orbital Shrinkage in Black Hole Low-mass X-Ray Binaries
Authors: Xu Xiao-Tian , Li Xiang-Dong
Published: May 2018

Several black hole low-mass X-ray binaries (BHLMXBs) show very fast orbital shrinkage, which is difficult to understand in the standard picture of the LMXB evolution. Based on the possible detection of a circumbinary (CB) disk in A0620-00 and XTE J1118+480, we investigate the influence of the interaction between a CB disk and the inner binary and calculate the evolution of the binary using the Modules for Experiments in Stellar Astrophysics. We consider two cases for the CB disk formation in which it is fed by mass loss during single outburst or successive outbursts in the LMXB. We show that when taking reasonable values of the initial mass and the dissipating time of the disk, it is possible to explain the fast orbital shrinkage in the BHLMXBs without invoking a high-mass transfer rate.
Growth of Beam–Plasma Instabilities in the Presence of Background Inhomogeneity
Authors: Shalaby Mohamad , Broderick Avery E. , Chang Philip , Pfrommer Christoph , Lamberts Astrid , Puchwein Ewald
Published: May 2018

We explore how inhomogeneity in the background plasma number density alters the growth of electrostatic unstable wavemodes of beam–plasma systems. This is particularly interesting for blazar-driven beam–plasma instabilities, which may be suppressed by inhomogeneities in the intergalactic medium (IGM) as was recently claimed in the literature. Using high-resolution particle-in-cell simulations with the SHARP code, we show that the growth of the instability is local, i.e., regions with almost homogeneous background density will support the growth of the Langmuir waves even when they are separated by strongly inhomogeneous regions, resulting in an overall slower growth of the instability. We also show that if the background density is continuously varying, the growth rate of the instability is lower, although in all cases the system remains within the linear regime longer and the instability is not extinguished. In all cases, the beam loses approximately the same fraction of its initial kinetic energy in comparison to the uniform case at nonlinear saturation. Thus, inhomogeneities in the IGM are unlikely to suppress the growth of blazar-driven beam–plasma instabilities.
Probing the Curious Case of a Galaxy Cluster Merger in Abell 115 with High-fidelity Chandra X-Ray Temperature and Radio Maps
Authors: Hallman Eric J. , Alden Brian , Rapetti David , Datta Abhirup , Burns Jack O.
Published: May 2018

We present results from an X-ray and radio study of the merging galaxy cluster Abell 115. We use the full set of five Chandra observations taken of A115 to date (360 ks total integration) to construct high-fidelity temperature and surface brightness maps. We also examine radio data from the Very Large Array at 1.5 GHz and the Giant Metrewave Radio Telescope at 0.6 GHz. We propose that the high X-ray spectral temperature between the subclusters results from the interaction of the bow shocks driven into the intracluster medium by the motion of the subclusters relative to one another. We have identified morphologically similar scenarios in Enzo numerical N-body/hydrodynamic simulations of galaxy clusters in a cosmological context. In addition, the giant radio relic feature in A115, with an arc-like structure and a relatively flat spectral index, is likely consistent with other shock-associated giant radio relics seen in other massive galaxy clusters. We suggest a dynamical scenario that is consistent with the structure of the X-ray gas, the hot region between the clusters, and the radio relic feature.
Specify Collections Consortium–Building Durable Infrastructure
Authors: Beach James
Published: May 2018

The Specify Software Project (www.specifysoftware.org) has been funded by the University of Kansas and with grants from the U.S. National Science Foundation for 20 years. In 2018, the effort is pivoting from a grant-funded project to a community-supported effort through the establishment of a consortium of biological collection institutions. Specify Collection Consortium software products will remain open source and free to download and use. Consortium membership benefits will include access to technical support services and seats on the Board of Directors and advisory committees, groups that will determine priorities for future products, platform capabilities, and technical support services. In 2017 and 2018, we have been engaged in organizational planning and development–modeling the Specify Collections Consortium on examples of viable open source and open access consortia in other research communities. Founding members of the Consortium in the U.S. include the University of Michigan, University of Florida, and University of Kansas. The Consortium's mission will be to support collections institutions in mobilizing data from their holdings to broader biological and computational initiatives to advance collections-based research, while facilitating efficient data curation and collection management. We will provide an update on our progress with the Consortium's development and highlight new capabilities and integration features of the Specify 6 & 7 software platforms.
Composition of gastrointestinal content, protease and lipase activities in summer and winter of four freshwater siluriforms (Teleostei: Actinopterygii) with two different feeding habits
Authors: Gottlieb Almeida Ana Paula , Zardo Everton Luis , Toni Candida , Behr Everton Rodolfo , Picolli da Silva Leila , Vieira João Paes , Loro Vania Lúcia , Baldisserotto Bernardo
Published: May 2018

The aim of this study was to determine the composition of gastrointestinal content and protease and lipase activities in summer and winter as well as to evaluate the relationship between digestive enzyme activity and centesimal composition of gastrointestinal content and feeding habits of two omnivorous species,Rhamdiaquelen(Quoy & Gaimard, 1824) andPimelodusmaculatus(LaCèpede, 1803), and of two detritivorous species,Loricariichthysanus(Valenciennes, 1835) andHypostomuscommersoni(Valenciennes, 1836). The activities of pepsin, trypsin, chymotrypsin, and lipase, and the levels of proteins and lipids in the gastrointestinal tract, were evaluated. The enzyme activities were not related to the centesimal composition of gastrointestinal content or feeding habits. This finding could be associated with the variations of nutrient availability over time in the environment, as was observed in the centesimal composition of food ingested by the fish in summer and winter. The analyzed enzymes exhibited a constitutive character in these species; that is, the digestive enzymes are always available in the gastrointestinal tract to digest any food that the fish may find as an adaptation to better utilize the nutrients available in the environment in winter and summer.