bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Azimuthal Variations Using Multi-Aperture Polarimetric Entropy with Circular SAR Images
Authors: Xue Feiteng , Lin Yun , Hong Wen , Yin Qiang , Zhang Bingchen , Shen Wenjie , Zhao Yue
Published: January 2018

In conventional synthetic aperture radar (SAR), sensors with a fixed look angle are assumed, and the scattering properties are considered as invariant in the azimuth. In some new SAR modes such as wide-angle SAR and circular SAR (CSAR), the azimuthal angle of view is much larger. Anisotropic targets which have different physical shapes from different angles of view are difficult to interpret in the traditional observation model if variations remain unconsidered. Meanwhile, SAR polarimetry is a powerful tool to analyze and interpret targets’ scattering properties. Anisotropic targets can be precisely described with polarimetric signatures from different angles of view. In this paper, polarimetric data is separated into sub-apertures to provide polarimetric properties from different angles of view. A multi-aperture observation model which contains full polarimetric information from all angles of view is then established. Based on the multi-aperture observation model, multi-aperture polarimetric entropy (MAPE) is defined and is suggested as an extension of polarimetric entropy in multi-aperture situations. MAPE describes both targets’ polarimetric properties and variations across sub-apertures. Variations across the azimuth are analyzed and anisotropic and isotropic targets are identified by MAPE. MAPE can be used in many polarimetric wide angle and CSAR applications. Potential applications in target discrimination and classification are discussed. The effectiveness and advantages of MAPE are demonstrated with polarimetric CSAR data acquired from the Institute of Electronics, Chinese Academy of Sciences airborne CSAR system at P-band.
Target Recognition in SAR Images Based on Information-Decoupled Representation
Authors: Chang Ming , You Xuqun
Published: January 2018

This paper proposes an automatic target recognition (ATR) method for synthetic aperture radar (SAR) images based on information-decoupled representation. A typical SAR image of a ground target can be divided into three parts: target region, shadow and background. From the aspect of SAR target recognition, the target region and shadow contain discriminative information. However, they also include some confusing information because of the similarities of different targets. The background mainly contains redundant information, which has little contribution to the target recognition. Because the target segmentation may impair the discriminative information in the target region, the relatively simpler shadow segmentation is performed to separate the shadow region for information decoupling. Then, the information-decoupled representations are generated, i.e., the target image, shadow and original image. The background is retained in the target image, which represents the coupling of target backscattering and background. The original image and generated target image are classified using the sparse representation-based classification (SRC). Then, their classification results are combined by a score-level fusion for target recognition. The shadow image is not used because of its lower discriminability and possible segmentation errors. To evaluate the performance of the proposed method, extensive experiments are conducted on the Moving and Stationary Target Acquisition and Recognition (MSTAR) dataset under both standard operating condition (SOC) and various extended operating conditions (EOCs). The proposed method can correctly classify 10 classes of targets with the percentage of correct classification (PCC) of 94.88% under SOC. With the PCCs of 93.15% and 75.03% under configuration variance and 45° depression angle, respectively, the superiority of the proposed is demonstrated in comparison with other methods. The robustness of the proposed method to both uniform and nonuniform shadow segmentation errors is validated with the PCCs over 93%. Moreover, with the maximum average precision of 0.9580, the proposed method is more effective than the reference methods on outlier rejection.
Trend Detection for the Extent of Irrigated Agriculture in Idaho’s Snake River Plain, 1984–2016
Authors: Chance Eric , Cobourn Kelly , Thomas Valerie
Published: January 2018

Understanding irrigator responses to changes in water availability is critical for building strategies to support effective management of water resources. Using remote sensing data, we examine farmer responses to seasonal changes in water availability in Idaho’s Snake River Plain for the time series 1984–2016. We apply a binary threshold based on the seasonal maximum of the Normalized Difference Moisture Index (NDMI) using Landsat 5–8 images to distinguish irrigated from non-irrigated lands. We find that the NDMI of irrigated lands increased over time, consistent with trends in irrigation technology adoption and increased crop productivity. By combining remote sensing data with geospatial data describing water rights for irrigation, we show that the trend in NDMI is not universal, but differs by farm size and water source. Farmers with small farms that rely on surface water are more likely than average to have a large contraction (over −25%) in irrigated area over the 33-year period of record. In contrast, those with large farms and access to groundwater are more likely than average to have a large expansion (over +25%) in irrigated area over the same period.
Comparison of the Spatial Characteristics of Four Remotely Sensed Leaf Area Index Products over China: Direct Validation and Relative Uncertainties
Authors: Li Xinlu , Lu Hui , Yu Le , Yang Kun
Published: January 2018

Leaf area index (LAI) is a key input for many land surface models, ecological models, and yield prediction models. In order to make the model simulation and/or prediction more reliable and applicable, it is crucial to know the characteristics and uncertainties of remotely sensed LAI products before they are input into models. In this study, we conducted a comparison of four global remotely sensed LAI products—Global Land Surface Satellite (GLASS), Global LAI Product of Beijing Normal University (GLOBALBNU), Global LAI Map of Chinese Academy of Sciences (GLOBMAP), and Moderate-resolution Imaging Spectrometer (MODIS) LAI, while the former three products are newly developed by three Chinese research groups on the basis of the MODIS land reflectance product over China between 2001 and 2011. Direct validation by comparing the four products to ground LAI observations both globally and over China demonstrates that GLASS LAI shows the best performance, with R2 = 0.70 and RMSE = 0.96 globally and R2 = 0.94 and RMSE = 0.61 over China; MODIS performs worst (R2 = 0.55, RMSE = 1.23 globally and R2 = 0.03, RMSE = 2.12 over China), and GLOBALBNU and GLOBMAP performs moderately. Comparison of the four products shows that they are generally consistent with each other, giving the smallest spatial correlation coefficient of 0.7 and the relative standard deviation around the order of 0.3. Compared with MODIS LAI, GLOBALBNU LAI is the most similar, followed by GLASS LAI and GLOBMAP. Large differences mainly occur in southern regions of China. LAI difference analysis indicates that evergreen needleleaf forest (ENF), woody savannas (SAV) biome types and temperate dry hot summer, temperate warm summer dry winter and temperate hot summer no dry season climate types correspond to high standard deviation, while ENF and grassland (GRA) biome types and temperate warm summer dry winter and cold dry winter warm summer climate types are responsible for the large relative standard deviation of the four products. Our results indicate that although the three newly developed products have improved the accuracy of LAI estimates, much work remains to improve the LAI products especially in ENF, SAV, and GRA regions and temperate climate zones. Findings from our study can provide guidance to communities regarding the performance of different LAI products over mainland China.
L-Band Temporal Coherence Assessment and Modeling Using Amplitude and Snow Depth over Interior Alaska
Authors: Eshqi Molan Yusuf , Kim Jin-Woo , Lu Zhong , Agram Piyush
Published: January 2018

Interferometric synthetic aperture radar (InSAR) provides the capability to detect surface deformation. Numerous processing approaches have been developed to improve InSAR results and overcome its limitations. Regardless of the processing methodology, however, temporal decorrelation is a major obstacle for all InSAR applications, especially over vegetated areas and dynamic environments, such as Interior Alaska. Temporal coherence is usually modeled as a univariate exponential function of temporal baseline. It has been, however, documented that temporal variations in surface backscattering due to the change in surface parameters, i.e., dielectric constant, roughness, and the geometry of scatterers, can result in gradual, seasonal, or sudden decorrelations and loss of InSAR coherence. The coherence models introduced so far have largely neglected the effect of the temporal change in backscattering on InSAR coherence. Here, we introduce a new temporal decorrelation model that considers changes in surface backscattering by utilizing the relative change in SAR intensity between two images as a proxy for the change in surface scattering parameters. The model also takes into account the decorrelation due to the change in snow depth between two images. Using the L-band Advanced Land Observation Satellite (ALOS-2) Phased Array type L-band Synthetic Aperture Radar (PALSAR-2) data, the model has been assessed over forested and shrub landscapes in Delta Junction, Interior Alaska. The model decreases the RMS error of temporal coherence estimation from 0.18 to 0.09 on average. The improvements made by the model have been statistically proved to be significant at the 99% confidence level. Additionally, the model shows that the coherence of forested areas are more prone to changes in backscattering than shrub landscape. The model is based on L-band data and may not be expanded to C-band or X-band InSAR observations.
Image Degradation for Quality Assessment of Pan-Sharpening Methods
Authors: Dou Wen
Published: January 2018

Wald’s protocol is the most widely accepted protocol to assess pan-sharpening algorithms. In particular, the synthesis property—which is usually validated on a reduced scale—is thought to be a necessary and sufficient condition of a success image fusion. Usually, the synthesis property is evaluated at a reduced resolution scale to take the original multispectral (MS) image as reference; thus, the image degradation method that is employed to produce reduced resolution images is crucial. In the past decade, the standard method has been to decimate the low-pass-filtered image where the filter is designed to match the modulation transfer function (MTF) of the sensor. The paper pointed out the deficiency of the method, and proposed a new image degradation method, referred to as method of spatial degradation for fusion validation (MSD4FV), which takes MTF compensation into account based on a simplified MTF model. The simulation results supported the implicit assumption of Wald’s protocol that image fusion performance is invariant among scales if the images have been properly degraded.
A 750 K Photocharge Linear Full Well in a 3.2 μm HDR Pixel with Complementary Carrier Collection
Authors: Lalanne Frédéric , Malinge Pierre , Hérault Didier , Jamin-Mornet Clémence , Virollet Nicolas
Published: January 2018

Mainly driven by automotive applications, there is an increasing interest in image sensors combining a high dynamic range (HDR) and immunity to the flicker issue. The native HDR pixel concept based on a parallel electron and hole collection for, respectively, a low signal level and a high signal level is particularly well-suited for this performance challenge. The theoretical performance of this pixel is modeled and compared to alternative HDR pixel architectures. This concept is proven with the fabrication of a 3.2 μm pixel in a back-side illuminated (BSI) process including capacitive deep trench isolation (CDTI). The electron-based image uses a standard 4T architecture with a pinned diode and provides state-of-the-art low-light performance, which is not altered by the pixel modifications introduced for the hole collection. The hole-based image reaches 750 kh+ linear storage capability thanks to a 73 fF CDTI capacitor. Both images are taken from the same integration window, so the HDR reconstruction is not only immune to the flicker issue but also to motion artifacts.
Influence of Concussion History and Genetics on Event-Related Potentials in Athletes: Potential Use in Concussion Management
Authors: Guth Taylor , Ketcham Caroline , Hall Eric
Published: January 2018

Sports-related concussions are an increasing public health issue with much concern about the possible long-term decrements in cognitive function and quality of life that may occur in athletes. The measurement of cognitive function is a common component of concussion management protocols due to cognitive impairments that occur after sustaining a concussion; however, the tools that are often used may not be sensitive enough to expose long term problems with cognitive function. The current paper is a brief review, which suggests that measuring cognitive processing through the use of event related potentials (ERPs) may provide a more sensitive assessment of cognitive function, as shown through recent research showing concussion history to influence ERPs components. The potential influence of genetics on cognitive function and ERPs components will also be discussed in relation to future concussion management.
Minimizing the Health Risks from Hydrocarbon Contaminated Soils by Using Electric Field-Based Treatment for Soil Remediation
Authors: Istrate Irina , Cocârță Diana , Wu Zucheng , Stoian Mihaela
Published: January 2018

The present work addresses the assessment of human health risk from soil contaminated with total petroleum hydrocarbons (TPHs) due to crude oil pollution, with a particular focus on the polycyclic aromatic hydrocarbon (PAH) group of carcinogenic and toxic substances. Given that the measured risk for human health exceeded the accepted level, the study considered an electrochemical remediation method. The laboratory-scale experiments were conducted by using an electric field-based treatment as a possible solution for the remediation of contaminated soil. After 20 days of treatment, while the voltage applied was 15 V (specific voltage of 1 V/cm), the hydrocarbon content was significantly reduced. The parameters measured to determine the overall remediation efficiency were pH, redox potential, ionic strength, soil characteristics, voltage gradient, and zeta potential. The remediation degree observed during the experiments was around 50% for TPHs and 46% for PAHs. The applied remediation method resulted in significant removal efficiency of the tested contaminants from the soil. Consequently, the human health risk assessment for the new degree of contaminants in the soil was achieved. This data demonstrated to what extent the application of the remediation applied technology ensured an acceptable risk under the same exposure conditions for the industrial workers.
Sustainable Energy Consumption in Northeast Asia: A Case from China’s Fuel Oil Futures Market
Authors: Zhang Chi , Pu Zhengning , Zhou Qin
Published: January 2018

The sustainable energy consumption in northeast Asia has a huge impact on regional stability and economic growth, which gives price volatility research in the energy market both theoretical value and practical application. We select China’s fuel oil futures market as a research subject and use recurrence interval analysis to investigate the price volatility pattern in different thresholds. We utilize the stretched exponential function to fit the pattern of the recurrence intervals of price fluctuations and find that the probability density functions of the recurrence intervals in different thresholds do not show the scaling behavior. Then the conditional probability density function and detrended fluctuation analysis prove that there is short-term and long-term correlation. Last, we use a hazard function to introduce the recurrence intervals into the (value at risk) VaR calculation and establish a functional relationship between the mean recurrence interval and the threshold. Following this result, we also shed light on policy discussion for hedgers and government.
Quantitative Analysis on the Influence Factors of the Sustainable Water Resource Management Performance in Irrigation Areas: An Empirical Research from China
Authors: Pan Hulin , Xu Qian
Published: January 2018

Performance evaluation and influence factors analysis are vital to the sustainable water resources management (SWRM) in irrigation areas. Based on the objectives and the implementation framework of modern integrated water resources management (IWRM), this research systematically developed an index system of the performances and their influence factors ones of the SWRM in irrigation areas. Using the method of multivariate regression combined with correlation analysis, this study estimated quantitatively the effect of multiple factors on the water resources management performances of irrigation areas in the Ganzhou District of Zhangye, Gansu, China. The results are presented below. The overall performance is mainly affected by management enabling environment and management institution with the regression coefficients of 0.0117 and 0.0235, respectively. The performance of ecological sustainability is mainly influenced by local economic development level and enable environment with the regression coefficients of 0.08642 and −0.0118, respectively. The performance of water use equity is mainly influenced by information publicity, administrators’ education level and ordinary water users’ participation level with the correlation coefficients of 0.637, 0.553 and 0.433, respectively. The performance of water use economic efficiency is mainly influenced by the management institutions and instruments with the regression coefficients of −0.07844 and 0.01808, respectively. In order to improve the overall performance of SWRM in irrigation areas, it is necessary to strengthen the public participation, improve the manager’ ability and provide sufficient financial support on management organization.
A Critical Examination of Geoengineering: Economic and Technological Rationality in Social Context
Authors: Gunderson Ryan , Petersen Brian , Stuart Diana
Published: January 2018

Geoengineering—specifically stratospheric aerosol injection—is not only risky, but supports powerful economic interests, protects an inherently ecologically harmful social formation, relegates the fundamental social-structural changes needed to address climate change, and is rooted in a vision of a nature as a set of passive resources that can be fully controlled in line with the demands of capital. The case for geoengineering is incomprehensible without analyzing the social context that gave birth to it: capitalism’s inability to overcome a contradiction between the need to accumulate capital, on the one hand, and the need to maintain a stable climate system on the other. Substantial emissions reductions, unlike geoengineering, are costly, rely more on social-structural than technical changes, and are at odds with the current social order. Because of this, geoengineering will increasingly be considered a core response to climate change. In light of Herbert Marcuse’s critical theory, the promotion of geoengineering as a market-friendly and high-tech strategy is shown to reflect a society that cannot set substantive aims through reason and transforms what should be considered means (technology and economic production) into ends themselves. Such a condition echoes the first-generation Frankfurt School’s central thesis: instrumental rationality remains irrational.
How Does Leader’s Support for Environment Promote Organizational Citizenship Behaviour for Environment? A Multi-Theory Perspective
Authors: Priyankara Hewawasam , Luo Fan , Saeed Amer , Nubuor Saviour , Jayasuriya Mahabaduge
Published: January 2018

Organizational citizenship behaviour for environment of employees is indispensable in realizing environmental sustainability goals of organizations. However, in the growing literature of employee green behaviour at work, scant attention has been paid on the impact of leader’s specific support for environment, and the mechanisms through which it impacts organizational citizenship behaviour for environment. Drawing upon social exchange theory, self-determination theory and theory of normative conduct, we tested the impact of leader’s support for environment, autonomous motivation for environment and perceived group’s green climate on organizational citizenship behaviour for environment in an integrated model. The sample included 313 executive level employees of green implemented textile and apparel manufacturing factories in Sri Lanka. The results of structural equation modelling showed a direct positive impact of leader’s support for environment on organizational citizenship behaviour for environment. Further, autonomous motivation for environment and perceived group’s green climate were found to be partial mediators between leader’s support for environment and organizational citizenship behaviour for environment. We discussed the theoretical implications for sustainability literature and the managerial implications for organizational practitioners in promoting organizational citizenship behaviour for environment.
Eco-Approach and Departure System for Left-Turn Vehicles at a Fixed-Time Signalized Intersection
Authors: Jiang Huifu , An Shi , Wang Jian , Cui Jianxun
Published: January 2018

This research proposed an eco-approach and departure system for left-turn vehicles at a fixed-time signalized intersection. This system gives higher priority to enhancing traffic safety than improving mobility and fuel efficiency, and optimizes the entire traffic consisted of connected and automated vehicles (CAVs) and conventional human-driven vehicles by providing ecological speed trajectories for left-turn CAVs. All the ecological speed trajectories are offline optimized before the implementation of system. The speed trajectory optimization is constructed in Pontryagin’s Minimum Principle structure. The before and after evaluation of the proposed system shows the percentage of vehicles that drive pass the intersection at safe speed increases by 2.14% to 45.65%, fuel consumption benefits range 0.53% to 18.44%, emission benefits range from 0.57% to 15.69%, no significant throughput benefits is observed. The proposed system significantly enhances the traffic safety and improves the fuel efficiency and emission reduction of left-turn vehicles with no adverse effect on mobility, and has a good robustness against the randomness of traffic. The investigation also indicates that the computation time of proposed system is greatly reduced compared to previous eco-driving system with online speed optimization. The computation time is up to 0.01 s. The proposed system is ready for real-time application.
Sustainability Index Evaluation of the Rainwater Harvesting System in Six US Urban Cities
Authors: Park Daeryong , Um Myoung-Jin
Published: January 2018

This study investigated the sustainability of the rainwater harvesting system (RWHS) by analyzing six urban city sites with different rainfall statistics in the United States. We developed a new RWHS performance model by modifying a spreadsheet-based storage, treatment, and overflow runoff model (SS STORM) and verified its performance by comparing with another analytical RWHS model. The sustainability index (SI) evaluation method was used for a reservoir system and applied to the RWHS, employing modified resilience and vulnerability evaluation methods due to the different characteristics of a reservoir and the RWHS. The performance of modified SS STORM is very similar to that of the analytical method, except in Los Angeles, which is characterized by long inter-event times and low rainfall event depths due to low annual rainfall. The sustainability indices were successfully evaluated depending on both RWHS size and water demand and vary over a wide range as annual rainfall increases. This study proposes a new RWHS performance model and sustainability index evaluation method. Further study should confirm the proposed approach in regions with widely different rainfall characteristics.
Sustainability-Oriented Innovation in the Minerals Industry: An Empirical Study on the Effect of Non-Geographical Proximity Dimensions
Authors: Ghassim Babak
Published: January 2018

Minerals mining and processing companies (hereinafter referred to as “minerals industry”) face the increasing demand for a comprehensive approach towards innovations aimed at sustainability. While the ability to learn from external sources of knowledge is at the core of this process, lack of geographical proximity and multiplicity of external sources impose challenges for mineral companies in this respect. The present study proposes that organizational, institutional and cognitive proximities could provide a platform for this industry to overcome those challenges, thereby achieving a superior innovation performance across various sustainability dimensions. Results of an analysis based on a sample of 101 mineral companies in Norway reveal that these dimensions of proximity are conducive to process, product and social innovation in different ways. More specifically, organizational proximity (diversity of non-local collaborations) and informal institutional proximity (shared cultural norms and values) spur social innovation. Furthermore, formal institutional proximity (similarity of rules and laws) and cognitive proximity (familiarity of knowledge base) support both process and product innovations. This paper provides some insights on the determinants of innovation in sustainability contexts, and contributes to the recent debate on the role of non-spatial proximity dimensions for innovation in the peripheral regions.
Graph Theory
Authors: Rodriguez Jose
Published: January 2018

This book contains the successful invited submissions [1–10] to a special issue of Symmetry on the subject area of ‘graph theory’ [...]
Announcing the 2018 Toxins Travel Awards for Post-Doctoral Fellows
Authors: Fox Jay
Published: January 2018

This year we enjoyed a large number of very highy meritorious applications for our annual Toxins Travel Awards.[...]
The ABC of Higher-Spin AdS/CFT
Authors: Giombi Simone , Klebanov Igor , Tan Zhong
Published: January 2018

In recent literature, one-loop tests of the higher-spin AdS d + 1 /CFT d correspondences were carried out. Here, we extend these results to a more general set of theories in d > 2 . First, we consider the Type B higher spin theories, which have been conjectured to be dual to CFTs consisting of the singlet sector of N free fermion fields. In addition to the case of N Dirac fermions, we carefully study the projections to Weyl, Majorana, symplectic and Majorana–Weyl fermions in the dimensions where they exist. Second, we explore theories involving elements of both Type A and Type B theories, which we call Type AB. Their spectrum includes fields of every half-integer spin, and they are expected to be related to the U ( N ) / O ( N ) singlet sector of the CFT of N free complex/real scalar and fermionic fields. Finally, we explore the Type C theories, which have been conjectured to be dual to the CFTs of p-form gauge fields, where p = d 2 − 1 . In most cases, we find that the free energies at O ( N 0 ) either vanish or give contributions proportional to the free-energy of a single free field in the conjectured dual CFT. Interpreting these non-vanishing values as shifts of the bulk coupling constant G N ∼ 1 / ( N − k ) , we find the values k = − 1 , − 1 / 2 , 0 , 1 / 2 , 1 , 2 . Exceptions to this rule are the Type B and AB theories in odd d; for them, we find a mismatch between the bulk and boundary free energies that has a simple structure, but does not follow from a simple shift of the bulk coupling constant.
Risk of Human Papillomavirus Infection in Cancer-Prone Individuals: What We Know
Authors: Khoury Ruby , Sauter Sharon , Butsch Kovacic Melinda , Nelson Adam , Myers Kasiani , Mehta Parinda , Davies Stella , Wells Susanne
Published: January 2018

Human papillomavirus (HPV) infections cause a significant proportion of cancers worldwide, predominantly squamous cell carcinomas (SCC) of the mucosas and skin. High-risk HPV types are associated with SCCs of the anogenital and oropharyngeal tract. HPV oncogene activities and the biology of SCCs have been intensely studied in laboratory models and humans. What remains largely unknown are host tissue and immune-related factors that determine an individual’s susceptibility to infection and/or carcinogenesis. Such susceptibility factors could serve to identify those at greatest risk and spark individually tailored HPV and SCC prevention efforts. Fanconi anemia (FA) is an inherited DNA repair disorder that is in part characterized by extreme susceptibility to SCCs. An increased prevalence of HPV has been reported in affected individuals, and molecular and functional connections between FA, SCC, and HPV were established in laboratory models. However, the presence of HPV in some human FA tumors is controversial, and the extent of the etiological connections remains to be established. Herein, we discuss cellular, immunological, and phenotypic features of FA, placed into the context of HPV pathogenesis. The goal is to highlight this orphan disease as a unique model system to uncover host genetic and molecular HPV features, as well as SCC susceptibility factors.
Zika Virus Fatally Infects Wild Type Neonatal Mice and Replicates in Central Nervous System
Authors: Li Shuxuan , Armstrong Najealicka , Zhao Huan , Hou Wangheng , Liu Jian , Chen Chunye , Wan Junkai , Wang Wei , Zhong Chunlian , Liu Che , Zhu Hua , Xia Ningshao , Cheng Tong , Tang Qiyi
Published: January 2018

Zika virus (ZIKV) has been defined as a teratogenic pathogen behind the increased number of cases of microcephaly in French Polynesia, Brazil, Puerto Rico, and other South American countries. Experimental studies using animal models have achieved tremendous insight into understanding the viral pathogenesis, transmission, teratogenic mechanisms, and virus–host interactions. However, the animals used in published investigations are mostly interferon (IFN)-compromised, either genetically or via antibody treatment. Herein, we studied ZIKV infection in IFN-competent mice using African (MR766) and Asian strains (PRVABC59 and SZ-WIV01). After testing four different species of mice, we found that BALB/c neonatal mice were resistant to ZIKV infection, that Kunming, ICR and C57BL/6 neonatal mice were fatally susceptible to ZIKV infection, and that the fatality of C57BL/6 neonates from 1 to 3 days old were in a viral dose-dependent manner. The size and weight of the brain were significantly reduced, and the ZIKV-infected mice showed neuronal symptoms such as hind-limb paralysis, tremor, and poor balance during walking. Pathologic and immunofluorescent experiments revealed that ZIKV infected different areas of the central nervous system (CNS) including gray matter, hippocampus, cerebral cortex, and spinal cord, but not olfactory bulb. Interestingly, ZIKV replicated in multiple organs and resulted in pathogenesis in liver and testis, implying that ZIKV infection may engender a high health risk in neonates by postnatal infection. In summary, we investigated ZIKV pathogenesis using an animal model that is not IFN-compromised.
Numerical Computation of Underground Inundation in Multiple Layers Using the Adaptive Transfer Method
Authors: Kim Hyung-Jun , Rhee Dong , Song Chang
Published: January 2018

Extreme rainfall causes surface runoff to flow towards lowlands and subterranean facilities, such as subway stations and buildings with underground spaces in densely packed urban areas. These facilities and areas are therefore vulnerable to catastrophic submergence. However, flood modeling of underground space has not yet been adequately studied because there are difficulties in reproducing the associated multiple horizontal layers connected with staircases or elevators. This study proposes a convenient approach to simulate underground inundation when two layers are connected. The main facet of this approach is to compute the flow flux passing through staircases in an upper layer and to transfer the equivalent quantity to a lower layer. This is defined as the ‘adaptive transfer method’. This method overcomes the limitations of 2D modeling by introducing layers connecting concepts to prevent large variations in mesh sizes caused by complicated underlying obstacles or local details. Consequently, this study aims to contribute to the numerical analysis of flow in inundated underground spaces with multiple floors.
Sedimentary Record of Cladoceran Functionality under Eutrophication and Re-Oligotrophication in Lake Maggiore, Northern Italy
Authors: Nevalainen Liisa , Brown Meghan , Manca Marina
Published: January 2018

We examined fossil Cladocera (Crustacea) communities and their functional assemblages in a ~60-year sediment record from Lake Maggiore, northern Italy. Our main objective was to document the response of aquatic community functioning to environmental stress during eutrophication (1960–1985) and recovery (post-1985), and to identify environmental controls on cladoceran functionality. Of the functional groups, large filter feeders and oval epibenthos thrived prior to eutrophication (reference conditions pre-1960) and globular epibenthos and small filter feeders increased during eutrophication and as the lake recovered. Multivariate analyses suggested that bottom-up controls (i.e., total phosphorus) were important for shaping functional assemblages but taxonomic community changes were likely related to top-down control by predators, particularly the predaceous cladoceran Bythotrephes longimanus. Functional diversity (FD) was higher and Daphnia ephippia length (DEL) larger during the reference and early eutrophication periods and decreased during eutrophication and recovery. Both FD (high) and DEL (large) were distinct during reference period, but were similar (FD low, DEL small) between the eutrophication and recovery periods. The functional attributes and the assemblages did not recover post-eutrophication, suggesting that the system exhibited a clear shift to low FD and dominance of small filterers. Cladoceran functionality appears to be related to fundamental ecosystem functions, such as productivity, and may thus provide insights for long-term changes in ecological resilience.
Synthesis and spectroscopic properties of β-meso directly linked porphyrin–corrole hybrid compounds
Authors: Temelli Baris , Kalkan Hilal
Published: January 2018

The preparation of β-meso directly linked porphyrin–corrole hybrids was realized for the first time via an InCl3-catalyzed condensation reaction of 2-formyl-5,10,15,20-tetraphenylporphyrins with meso-substituted dipyrromethanes. Hybrid compounds have been characterized by 1H NMR, 13C NMR, 2D NMR, UV–vis absorption and fluorescence spectroscopy.
Kinematics of the Horsehead Nebula and IC 434 Ionization Front in CO and C+
Authors: Bally John , Chambers Ed , Guzman Viviana , Keto Eric , Mookerjea Bhaswati , Sandell Goran , Stanke Thomas , Zinnecker Hans
Published: January 2018

Stratospheric Observatory for Infrared Astronomy [C ii] 157 μm, APEX 860 μm J = 3−2 CO, and archival James Clerk Maxwell Telescope J = 2−1 CO and 13CO observations of the Horsehead Nebula are presented. The photon-dominated region (PDR) between the Orion B molecular cloud and the adjacent IC 434 H ii region is used to study the radial velocity structure of the region and the feedback impacts of UV radiation. Multiple west-facing cloud edges are superimposed along the line of sight with radial velocities that differ by a few kilometers per second. The Horsehead lies in the foreground blueshifted portion of the Orion B molecular cloud and is predominantly illuminated from the rear. The mean H2 density of the Horsehead,

, results in a spatially thin PDR where the photoablation flow has compressed the western cloud edge to an H2 density of

. The associated [C ii] 157 μm layer has a width L < 0.05 pc. The background parts of the Orion B cloud in the imaged field consist of a clumpy medium surrounded by molecular gas with H2 densities lower by one to two orders of magnitude. Along the straight part of the IC 434 ionization front, the PDR layer probed by [C ii] 157 μm emission is much thicker with L ∼ 0.5 pc. A possible model for the formation and evolution of this edge-on ionization front and PDR is presented. The [C ii] data were independently analyzed and published by Pabst et al.
HATS-50b through HATS-53b: Four Transiting Hot Jupiters Orbiting G-type Stars Discovered by the HATSouth Survey*
Authors: Henning Th. , Mancini L. , Sarkis P. , Bakos G. Á. , Hartman J. D. , Bayliss D. , Bento J. , Bhatti W. , Brahm R. , Ciceri S. , Csubry Z. , Val-Borro M. de , Espinoza N. , Fulton B. J. , Howard A. W. , Isaacson H. T. , Jordán A. , Marcy G. W. , Penev K. , Rabus M. , Suc V. , Tan T. G. , Tinney C. G. , Wright D. J. , Zhou G. , Durkan S. , Lazar J. , Papp I. , Sari P.
Published: January 2018

We report the discovery of four close-in transiting exoplanets (HATS-50b through HATS-53b), discovered using the HATSouth three-continent network of homogeneous and automated telescopes. These new exoplanets belong to the class of hot Jupiters and orbit G-type dwarf stars, with brightness in the range V = 12.5–14.0 mag. While HATS-53 has many physical characteristics similar to the Sun, the other three stars appear to be metal-rich (

), larger, and more massive. Three of the new exoplanets, namely HATS-50b, HATS-51b, and HATS-53b, have low density (HATS-50b:

,

; HATS-51b:

,

; HATS-53b:

,

) and similar orbital periods (

days,

days,

days, respectively). Instead, HATS-52b is more dense (mass

and radius

) and has a shorter orbital period (

days). It also receives an intensive radiation from its parent star and, consequently, presents a high equilibrium temperature (

K). HATS-50 shows a marginal additional transit feature consistent with an ultra-short-period hot super Neptune (upper mass limit 0.16

), which will be able to be confirmed with TESS photometry.
Bayesian Model Testing of Ellipsoidal Variations on Stars due to Hot Jupiters
Authors: Gai Anthony D. , Knuth Kevin H.
Published: January 2018

A massive planet closely orbiting its host star creates tidal forces that distort the typically spherical stellar surface. These distortions, known as ellipsoidal variations, result in changes in the photometric flux emitted by the star, which can be detected within the data from the Kepler Space Telescope. Currently, there exist several models describing such variations and their effect on the photometric flux. By using Bayesian model testing in conjunction with the Bayesian-based exoplanet characterization software package EXONEST, the most probable representation for ellipsoidal variations was determined for synthetic data and the confirmed hot Jupiter exoplanet Kepler-13A b. The most preferred model for ellipsoidal variations observed in the Kepler-13 light curve was determined to be EVIL-MC. Among the trigonometric models, the Modified Kane & Gelino model provided the best representation of ellipsoidal variations for the Kepler-13 system and may serve as a fast alternative to the more computationally intensive EVIL-MC. The computational feasibility of directly modeling the ellipsoidal variations of a star are examined and future work is outlined. Providing a more accurate model of ellipsoidal variations is expected to result in better planetary mass estimations.
The Origin and Evolution of Nucleosynthetic Sr Isotope Variability in Calcium and Aluminum-rich Refractory Inclusions
Authors: Myojo Kunihiro , Yokoyama Tetsuya , Okabayashi Satoki , Wakaki Shigeyuki , Sugiura Naoji , Iwamori Hikaru
Published: January 2018

Nucleosynthetic isotope anomalies in meteorites are useful for investigating the origin of materials in the protoplanetary disk and dynamical processes of planetary formation. In particular, calcium and aluminum-rich inclusions (CAIs) found in chondrites are key minerals for decoding the initial conditions of the solar system before the accretion of small planetary bodies. In this study, we report isotopic analyses for three Allende CAIs, fluffy type A (FTA), type B, and fine-grained spinel rich (FS) inclusions, with a specific emphasis on the measurements of 84Sr/86Sr ratios. It was found that the average μ
84Sr values (106 relative deviations from a standard material) were 175, 129, and 56 ppm for the samples of FTA, type B, and FS inclusions, respectively. Additionally, the FTA samples exhibited heterogeneous μ
84Sr values, while those for the type B and FS inclusions were homogeneous within individual inclusions. The elevated μ
84Sr values were most likely explained by the relative enrichment of r-process nuclides in the CAI formation region. The variation of μ
84Sr values between the FTA and type B inclusions, as well as within the FTA inclusion, suggests the presence of multiple CAI source reservoirs with distinct isotopic compositions, which is either inherited from isotopic heterogeneity in the molecular cloud or caused by the selective destruction of r-process-enriched supernova grains via nebular thermal processing. On the other hand, the reaction between a refractory precursor of the FS inclusion and a gaseous reservoir enriched in Mg, Si, and 16O resulted in the lowest μ
84Sr values for the FS inclusion.
“Red” but Not “Dead”: Actively Star-forming Brightest Cluster Galaxies at Low Redshifts
Authors: Runge James , Yan Haojing
Published: January 2018

Brightest cluster galaxies (BCGs) are believed to have assembled most of their stars early in time and therefore should be passively evolving at low redshifts and appear “red-and-dead.” However, there have been reports that a minority of low-redshift BCGs still have ongoing star formation rates (SFRs) of a few to even

. Such BCGs are found in “cool-core” (“CC”) clusters, and their star formation is thought to be fueled by “cooling flow.” To further investigate the implications of low-redshift, star-forming BCGs, we perform a systematic search using the 22 μm data (“W4” band) from the Wide-field Infrared Survey Explorer (WISE) on the GMBCG catalog, which contains 55,424 BCGs at

identified in the Sloan Digital Sky Survey (SDSS). Our sample consists of 389 BCGs that are bright in W4 (“W4BCGs”), most being brighter than 5 mJy. While some (

) might host active galactic nuclei, most W4BCGs should owe their strong mid-IR emissions to dust-enshrouded star formation. Their median total IR luminosity (L
IR) is

(SFR ∼50

, and 27% of the whole sample has

(SFR >100

). Using 10 W4BCGs that have Chandra X-ray data, we show that 7 of them are possibly in CC clusters. However, in most cases (five out of seven) the mass deposition rate cannot account for the observed SFR. This casts doubt on the idea that cooling flows are the cause of the star formation in non-quiescent BCGs.
Supercritical Accretion onto a Non-magnetized Neutron Star: Why is it Feasible?
Authors: Takahashi Hiroyuki R. , Mineshige Shin , Ohsuga Ken
Published: January 2018

To understand why supercritical accretion is feasible onto a neutron star (NS), we carefully examine the accretion flow dynamics by 2.5-dimensional general relativistic radiation magnetohydrodynamic (RMHD) simulations, comparing the cases of accretion onto a non-magnetized NS and that onto a black hole (BH). Supercritical BH accretion is relatively easy, since BHs can swallow excess radiation energy, so that radiation flux can be inward in its vicinity. This mechanism can never work for an NS, which has a solid surface. In fact, we find that the radiation force is always outward. Instead, we found significant reduction in the mass accretion rate due to strong radiation-pressure-driven outflow. The radiation flux F
rad is self-regulated such that the radiation force balances with the sum of gravity and centrifugal forces. Even when the radiation energy density greatly exceeds that expected from the Eddington luminosity

E

rad

≃

F

rad

τ

/

c
>

10

2

L

Edd

/

(
4
π

r

2

c
)

, the radiation flux is always kept below a certain value, which makes it possible not to blow all the gas away from the disk. These effects make supercritical accretion feasible. We also find that a settling region, where accretion is significantly decelerated by a radiation cushion, is formed around the NS surface. In the settling region, the radiation temperature and mass density roughly follow

T

rad

∝

r

−
1

and

ρ
∝

r

−
3

, respectively. No settling region appears around the BH, so matter can be directly swallowed by the BH with supersonic speed.
On the Synchrotron Spectrum of GRB Prompt Emission
Authors: Xu Siyao , Yang Yuan-Pei , Zhang Bing
Published: January 2018

The prompt emission spectrum of gamma-ray bursts is characterized by a smoothly joint broken power-law spectrum known as the Band function. The typical low-energy photon index is

, which poses a challenge to standard synchrotron radiation models. We investigate the electron energy spectrum as a result of the interplay among adiabatic stochastic acceleration (ASA), particle injection, and synchrotron cooling. In the ASA-dominated low-energy range, ASA enables an efficient hardening of the injected energy spectrum to approach a spectral index −1. In the synchrotron cooling-dominated high-energy range, the injected high-energy electrons undergo fast synchrotron cooling and have a softer photon spectrum. With the energy range of the injected electrons broadly covering both the ASA- and synchrotron cooling-dominated ranges, the resulting photon number spectrum has low- and high-energy indices of

and

, respectively. The break energy is of the order of ∼100 keV, depending on the turbulence properties.
Magnetized Disk Winds in NGC 3783
Authors: Fukumura Keigo , Kazanas Demosthenes , Shrader Chris , Behar Ehud , Tombesi Francesco , Contopoulos Ioannis
Published: January 2018

We analyze a 900 ks stacked Chandra/HETG spectrum of NGC 3783 in the context of magnetically driven accretion-disk wind models in an effort to provide tight constraints on the global conditions of the underlying absorbers. Motivated by the earlier measurements of its absorption measure distribution (AMD) indicating X-ray-absorbing ionic columns that decrease slowly with decreasing ionization parameter, we employ 2D magnetohydrodynamic (MHD) disk wind models to describe the global outflow. We compute its photoionization structure along with the wind kinematic properties, allowing us to further calculate in a self-consistent fashion the shapes of the major X-ray absorption lines. With the wind radial density profile determined by the AMD, the profiles of the ensemble of the observed absorption features are determined by the two global parameters of the MHD wind; i.e., disk inclination

and wind density normalization n

o
. Considering the most significant absorption features in the ∼1.8–20 Å range, we show that the MHD wind is best described by

cm−3 and

. We argue that winds launched by X-ray heating or radiation pressure, or even MHD winds but with steeper radial density profiles, are strongly disfavored by data. Considering the properties of Fe K-band absorption features (i.e., Fe xxv and Fe xxvi), while typically prominent in the active galactic nucleus X-ray spectra, they appear to be weak in NGC 3783. For the specific parameters of our model obtained by fitting the AMD and the rest of the absorption features, these features are found to be weak, in agreement with observations.