bluuebunny/crossref_metadata_2025 huggingface dataset:
An Improved Electronic Image Motion Compensation (IMC) Method of Aerial Full-Frame-Type Area Array CCD Camera Based on the CCD Multiphase Structure and Hardware Implementation
Authors: Ren Hang , Hu Tao Tao , Song Yu Long , Sun Hui , Liu Bo Chao , Gao Ming He
Published: August 2018

In this paper, the performance of the electronic conventional image motion compensation (IMC) method based on the time delay integration (TDI) mode was analyzed using the optical injection formula of charge coupled devices (CCDs). The result shows that the non-synchronous effect of charge packet transfer caused by line-by-line transfer during exposure makes the compensated image dissatisfying. Then an improved electronic IMC method based on the CCD multiphase structure was proposed. In this method, a series of proper driving clocks were applied to drive the charge packet to move electrode-by-electrode during the exposure time, which results in a minimum non-synchronous effect of charge packet transfer. The mismatch of velocity between charge packet transfer and image motion was decreased. The performance of the improved electronic IMC method was also analyzed using the optical injection formula. The modulation degrees of the two methods were compared. The average value of the modulation degree of the improved electronic IMC method was 47/96, greater than the conventional electronic IMC method, which was 1/3. To achieve the improved electronic IMC, the driver timing diagram of the improved electronic IMC method was proposed. This paper presented an improved hardware implementation method for the improved electronic IMC method. Based on the basic FTF4052M drive circuit system, an IMC pulse pattern generator that worked together with the main pulse pattern generator (SAA8103) was added to achieve the improved electronic IMC. Then, the internal structure of the IMC pulse pattern generator was given. A dual pulse pattern generator drive circuit system was proposed. After computer simulation and indoor real shot verification, the compensation effect of the improved electronic IMC method was better than the compensation effect of the conventional electronic IMC method.
Spatial Extension of Road Traffic Sensor Data with Artificial Neural Networks
Authors: Gallo Mariano , De Luca Giuseppina
Published: August 2018

This paper proposes a method for estimating traffic flows on some links of a road network knowing the data on other links that are monitored with sensors. In this way, it is possible to obtain more information on traffic conditions without increasing the number of monitored links. The proposed method is based on artificial neural networks (ANNs), wherein the input data are the traffic flows on some monitored road links and the output data are the traffic flows on some unmonitored links. We have implemented and tested several single-layer feed-forward ANNs that differ in the number of neurons and the method of generating datasets for training. The proposed ANNs were trained with a supervised learning approach where input and output example datasets were generated through traffic simulation techniques. The proposed method was tested on a real-scale network and gave very good results if the travel demand patterns were known and used for generating example datasets, and promising results if the demand patterns were not considered in the procedure. Numerical results have underlined that the ANNs with few neurons were more effective than the ones with many neurons in this specific problem.
Adaptive Discrete Vector Field in Sensor Networks
Authors: Zhang Mengyi , Goupil Alban
Published: August 2018

Homology groups are a prime tool for measuring the connectivity of a network, and their computation in a distributed and adaptive way is mandatory for their use in sensor networks. In this paper, we propose a solution based on the construction of an adaptive discrete vector field from where, thanks to the discrete Morse theory, the generators of the homology groups are extracted. The efficiency and the adaptability of our approach are tested against two applications: the detection and the localization of the holes in the coverage, and the selection of active sensors ensuring complete coverage.
An Efficient Sampling-Based Algorithms Using Active Learning and Manifold Learning for Multiple Unmanned Aerial Vehicle Task Allocation under Uncertainty
Authors: Fu Xiaowei , Wang Hui , Li Bin , Gao Xiaoguang
Published: August 2018

This paper presents a sampling-based approximation for multiple unmanned aerial vehicle (UAV) task allocation under uncertainty. Our goal is to reduce the amount of calculations and improve the accuracy of the algorithm. For this purpose, Gaussian process regression models are constructed from an uncertainty parameter and task reward sample set, and this training set is iteratively refined by active learning and manifold learning. Firstly, a manifold learning method is used to screen samples, and a sparse graph is constructed to represent the distribution of all samples through a small number of samples. Then, multi-points sampling is introduced into the active learning method to obtain the training set from the sparse graph quickly and efficiently. This proposed hybrid sampling strategy could select a limited number of representative samples to construct the training set. Simulation analyses demonstrate that our sampling-based algorithm can effectively get a high-precision evaluation model of the impact of uncertain parameters on task reward.
The Implications of Fragmented Genomic DNA Size Range on the Hybridization Efficiency in NanoGene Assay
Authors: Wang Xiaofang , Chua Beelee , Son Ahjeong
Published: August 2018

DNA hybridization-based assays are well known for their ability to detect and quantify specific bacteria. Assays that employ DNA hybridization include a NanoGene assay, fluorescence in situ hybridization, and microarrays. Involved in DNA hybridization, fragmentation of genomic DNA (gDNA) is necessary to increase the accessibility of the probe DNA to the target gDNA. However, there has been no thorough and systematic characterization of different fragmented gDNA sizes and their effects on hybridization efficiency. An optimum fragmented size range of gDNA for the NanoGene assay is hypothesized in this study. Bacterial gDNA is fragmented via sonication into different size ranges prior to the NanoGene assay. The optimum size range of gDNA is determined via the comparison of respective hybridization efficiencies (in the form of quantification capabilities). Different incubation durations are also investigated. Finally, the quantification capability of the fragmented (at optimum size range) and unfragmented gDNA is compared.
Design, Implementation and Practical Evaluation of an IoT Home Automation System for Fog Computing Applications Based on MQTT and ZigBee-WiFi Sensor Nodes
Authors: Froiz-Míguez Iván , Fernández-Caramés Tiago M. , Fraga-Lamas Paula , Castedo Luis
Published: August 2018

In recent years, the improvement of wireless protocols, the development of cloud services and the lower cost of hardware have started a new era for smart homes. One such enabling technologies is fog computing, which extends cloud computing to the edge of a network allowing for developing novel Internet of Things (IoT) applications and services. Under the IoT fog computing paradigm, IoT gateways are usually utilized to exchange messages with IoT nodes and a cloud. WiFi and ZigBee stand out as preferred communication technologies for smart homes. WiFi has become very popular, but it has a limited application due to its high energy consumption and the lack of standard mesh networking capabilities for low-power devices. For such reasons, ZigBee was selected by many manufacturers for developing wireless home automation devices. As a consequence, these technologies may coexist in the 2.4 GHz band, which leads to collisions, lower speed rates and increased communications latencies. This article presents ZiWi, a distributed fog computing Home Automation System (HAS) that allows for carrying out seamless communications among ZigBee and WiFi devices. This approach diverges from traditional home automation systems, which often rely on expensive central controllers. In addition, to ease the platform’s building process, whenever possible, the system makes use of open-source software (all the code of the nodes is available on GitHub) and Commercial Off-The-Shelf (COTS) hardware. The initial results, which were obtained in a number of representative home scenarios, show that the developed fog services respond several times faster than the evaluated cloud services, and that cross-interference has to be taken seriously to prevent collisions. In addition, the current consumption of ZiWi’s nodes was measured, showing the impact of encryption mechanisms.
RFID Technology for Management and Tracking: e-Health Applications
Authors: Álvarez López Yuri , Franssen Jacqueline , Álvarez Narciandi Guillermo , Pagnozzi Janet , González-Pinto Arrillaga Ignacio , Las-Heras Andrés Fernando
Published: August 2018

Radio frequency identification (RFID) has become a key technology in the logistics and management industry, thanks to distinctive features such as the low cost of RFID tags, and the easiness of the RFID tags’ deployment and integration within the items to be tracked. In consequence, RFID plays a fundamental role in the so-called digital factory or 4.0 Industry, aiming to increase the level of automatization of industrial processes. In addition, RFID has also been found to be of great help in improving the tracking of patients, medicines, and medical assets in hospitals, where the digitalization of these operations improves their efficiency and safety. This contribution reviews the state-of-the-art of RFID for e-Health applications, describing the contributions to improve medical services and discussing the limitations. In particular, it has been found that a lot of effort has been put into software development, but in most of the cases a detailed study of the physical layer (that is, the characterization of the RFID signals within the area where the system is deployed) is not properly conducted. This contribution describes a basic RFID system for tracking and managing assets in hospitals, aiming to provide additional details about implementation aspects that must be considered to ensure proper functionality of the system. Although the scope of the RFID system described in this contribution is restricted to a small area of the hospital, the architecture is fully scalable to cover the needs of the different medical services in the hospital. Ultra high-frequency (UHF) RFID technology is selected over the most extended near-field communication (NFC) and high-frequency (HF) RFID technology to minimize hardware infrastructure. In particular, UHF RFID also makes the coverage/reading area conformation easier by using different kinds of antennas. Information is stored in a database, which is accessed from end-user mobile devices (tablets, smartphones) where the position and status of the assets to be tracked are displayed.
Estimating the Blue Water Footprint of In-Field Crop Losses: A Case Study of U.S. Potato Cultivation
Authors: Spang Edward S. , Stevens Bret D.
Published: August 2018

Given the high proportion of water consumption for agriculture, as well as the relatively common occurrence of crop losses in the field, we estimate the amount of water embedded in crops left on the farm. We are particularly interested in understanding losses associated with fruits and vegetables, having a higher level of harvesting selectivity and perishability (and thus, losses) than grain crops. We further refined the study to focus on potatoes, as they represent the largest acreage under cultivation of all fruit and vegetable crops in the U.S. We attempt to get the most complete understanding of pre-harvest and harvest loss data for potatoes by leveraging three centralized data sets collected and managed by the United States Department of Agriculture (USDA). By integrating these three distinct data sets for the five-year period 2012–2016, we are able to estimate water consumption for potato cultivation for total in-field losses by production stage and driver of loss for seven major potato-producing states (representing 77% of total U.S. potato production). Our results suggest that 3.6%–17.9% of potatoes are lost in the field with a total estimated blue water footprint of approximately 84.6 million cubic meters. We also find that the leading driver for crop loss for in-field potato production is harvest sorting and grading, accounting for 84% of total lost production at the farm. We conclude with a discussion of opportunities for improved national level data collection to provide a better understanding of in-field crop losses over time and the resource footprints of these losses.
A Review of Green Roof Applications for Managing Urban Stormwater in Different Climatic Zones
Authors: Akther Musa , He Jianxun , Chu Angus , Huang Jian , Van Duin Bert
Published: August 2018

Many regions have turned to low impact development technologies (LIDs), which are implemented to restore the changes in stormwater runoff that have resulted from urbanization. Green roofs are one typical type of LID. Until now, many studies have validated their roles in managing urban stormwater runoff. However, they have also revealed that the performance of green roofs largely varies with their design configuration, as well as their hydro-climatic exposure. The objectives of this review paper are to statistically synthesize the effects of the influential factors, including design and hydrologic variables, on green roof performance and to explore their effects in different climatic zones. The review’s results confirm the differences in the influential variables and, thus, the performance of green roofs in different climatic zones. These are the barriers to knowledge translation among engineering designers, stormwater managers, and policymakers in different climatic zones when implementing green roofs. Consequently, region- or site-specific studies are necessary to implement green roofs with confidence.
Impacts of Freight Transport on PM2.5 Concentrations in China: A Spatial Dynamic Panel Analysis
Authors: Wang Yan , Yang Dong
Published: August 2018

Freight transport policies have been developed to reduce air pollution in China. This paper aims to evaluate the impact of a freight modal shift on PM2.5 concentrations using the panel data of 30 provinces in China over the period 1999–2016. The direct and spillover effects of a freight modal shift on PM2.5 concentrations in China, as well as the effects of other socioeconomic factors, were estimated by employing spatial dynamic panel data models. In particular, the channel through which the freight modal shift might be beneficial in reducing PM2.5 concentrations was examined. The results show that PM2.5 concentrations in China do not only decrease with a modal shift of freight from road to rail in a province, but also and to a larger extent with that in neighboring provinces. However, there exist heterogeneous effects across different regions of China. The interaction between a freight modal shift and energy efficiency may lead to a decrease in the PM2.5 concentrations, but only in the central and western regions. These findings provide suggestions for government policies directed to sustainable development.
The Impact of Electric Vehicle Demand and Battery Recycling on Price Dynamics of Lithium-Ion Battery Cathode Materials: A Vector Error Correction Model (VECM) Analysis
Authors: Mo Jung Youn , Jeon Wooyoung
Published: August 2018

The recent rise in demand for electric vehicles (EV) and energy storage supporting power systems has increased the demand for lithium-ion batteries (LIB), and it is expected to be more significant in near future. However, materials for LIB, such as lithium and cobalt, may face limited supply due to oligopolistic market characteristics, and this can have a significant impact on prices of LIB materials. This paper examines the dynamics of LIB raw material prices (cobalt, lithium, nickel, and manganese prices) with EV demand using the Vector Error Correction Model (VECM) method. The result shows that the EV demand is important in short-run dynamics of cobalt and lithium prices, which indicates that the recent increase in lithium and cobalt prices has been caused by increase in EV demand. In the long-run equilibrium, lithium and nickel prices move inversely with cobalt prices. The impulse response results confirm that EV demand has an immediate positive effect on cobalt price, and the effect maintains over two years. On the other hand, the EV demand shock to nickel, lithium, and manganese prices is relatively small. This study also analyses the impact of recycling policy of LIB on material prices. Finally, the paper discusses the policy implications for stabilizing material prices of LIB.
Steganalysis of Inactive Voice-Over-IP Frames Based on Poker Test
Authors: Liu Jie , Tian Hui , Chang Chin-Chen , Wang Tian , Chen Yonghong , Cai Yiqiao
Published: August 2018

This paper concentrates on the detection of steganography in inactive frames of low bit rate audio streams in Voice over Internet Protocol (VoIP) scenarios. Both theoretical and experimental analyses demonstrate that the distribution of 0 and 1 in encoding parameter bits becomes symmetric after a steganographic process. Moreover, this symmetry affects the frequency of each subsequence of parameter bits, and accordingly changes the poker test statistical features of encoding parameter bits. Employing the poker test statistics of each type of encoding parameter bits as detection features, we present a steganalysis method based on a support vector machine. We evaluate the proposed method with a large quantity of speech samples encoded by G.723.1 and compare it with the entropy test. The experimental results show that the proposed method is effective, and largely outperforms the entropy test in any cases.
FCNS: A Fuzzy Routing-Forwarding Algorithm Exploiting Comprehensive Node Similarity in Opportunistic Social Networks
Authors: Liu Kanghuai , Chen Zhigang , Wu Jia , Wang Leilei
Published: August 2018

At the dawn of big data and 5G networks, end-to-end communication with large amounts of data between mobile devices is difficult to be implemented through the traditional face-to-face transmission mechanism in social networks. Consequently, opportunistic social networks proposed that message applications should choose proper relay nodes to perform effective data transmission processes. At present, several routing algorithms, based on node similarity, attempt to use the contextual information related to nodes and the special relationships between them to select a suitable relay node among neighbors. However, when evaluating the similarity degree between a pair of nodes, most existing algorithms in opportunistic social networks pay attention to only a few similar factors, and even ignore the importance of mobile similarity in the data transmission process. To improve the transmission environment, this study establishes a fuzzy routing-forwarding algorithm (FCNS) exploiting comprehensive node similarity (the mobile and social similarities) in opportunistic social networks. In our proposed scheme, the transmission preference of the node is determined through the fuzzy evaluation of mobile and social similarities. The suitable message delivery decision is made by collecting and comparing the transmission preference of nodes, and the sustainable and stable data transmission process is performed through the feedback mechanism. Through simulations and the comparison of social network algorithms, the delivery ratio in the proposed algorithm is 0.85 on average, and the routing delay and network overhead of this algorithm are always the lowest.
A Three-Dimensional Constrained Ordered Weighted Averaging Aggregation Problem with Lower Bounded Variables
Authors: Chen Yi-Fang , Tang Hui-Chin
Published: August 2018

We consider the constrained ordered weighted averaging (OWA) aggregation problem with a single constraint and lower bounded variables. For the three-dimensional constrained OWA aggregation problem with lower bounded variables, we present four types of solution depending on the number of zero elements. According to the computerized experiment we perform, the lower bounds can affect the solution types, thereby affecting the optimal solution of the three-dimensional constrained OWA aggregation problem with lower bounded variables.
Potent HIV-1-Specific CD8 T Cell Responses Induced in Mice after Priming with a Multiepitopic DNA-TMEP and Boosting with the HIV Vaccine MVA-B
Authors: Perdiguero Beatriz , Raman Suresh C. , Sánchez-Corzo Cristina , S. Sorzano Carlos Oscar , Valverde José Ramón , Esteban Mariano , Gómez Carmen Elena
Published: August 2018

An effective vaccine against Human Immunodeficiency Virus (HIV) still remains the best solution to provide a sustainable control and/or eradication of the virus. We have previously generated the HIV-1 vaccine modified vaccinia virus Ankara (MVA)-B, which exhibited good immunogenicity profile in phase I prophylactic and therapeutic clinical trials, but was unable to prevent viral rebound after antiretroviral (ART) removal. To potentiate the immunogenicity of MVA-B, here we described the design and immune responses elicited in mice by a new T cell multi-epitopic B (TMEP-B) immunogen, vectored by DNA, when administered in homologous or heterologous prime/boost regimens in combination with MVA-B. The TMEP-B protein contained conserved regions from Gag, Pol, and Nef proteins including multiple CD4 and CD8 T cell epitopes functionally associated with HIV control. Heterologous DNA-TMEP/MVA-B regimen induced higher HIV-1-specific CD8 T cell responses with broader epitope recognition and higher polyfunctional profile than the homologous DNA-TMEP/DNA-TMEP or the heterologous DNA-GPN/MVA-B combinations. Moreover, higher HIV-1-specific CD4 and Tfh immune responses were also detected using this regimen. After MVA-B boost, the magnitude of the anti-VACV CD8 T cell response was significantly compromised in DNA-TMEP-primed animals. Our results revealed the immunological potential of DNA-TMEP prime/MVA-B boost regimen and supported the application of these combined vectors in HIV-1 prevention and/or therapy.
Vibration Suppression and Energy Harvesting with a Non-traditional Vibration Absorber: Transient Responses
Authors: Yuan Miao , Liu Kefu
Published: August 2018

This paper focuses on vibration suppression and energy harvesting using a non-traditional vibration absorber referred to as model B. Unlike the traditional vibration absorber, model B has its damper connected between the absorber mass and ground. The apparatus used in the study consists of a cantilever beam attached by a mass at its free end and an electromagnetic energy harvester. The frequency tuning is achieved by varying the beam length while the damping tuning is realized by varying the harvester load resistance. The question addressed is how to achieve the best performance under transient responses. The optimum tuning condition for vibration suppression is based on the Stability Maximization Criterion (SMC). The performance of energy harvesting is measured by the percentage of the harvested energy to the input energy. A computer simulation is conducted. The results validate the optimum parameters derived by the SMC. There is a trade-off between vibration suppression and energy harvesting within the realistic ranges of the frequency tuning ratio and damping ratio. A multi-objective optimization is conducted. The results provide a guideline for obtaining a balanced performance. An experimental study is carried out. The results verify the main findings from the computer simulation. This study shows that the developed apparatus is capable of achieving simultaneous vibration suppression and energy harvesting under transient responses.
Bacterial Productivity in a Ferrocyanide-Contaminated Aquifer at a Nuclear Waste Site
Authors: Plymale Andrew , Wells Jacqueline , Graham Emily , Qafoku Odeta , Brooks Shelby , Lee Brady
Published: August 2018

This study examined potential microbial impacts of cyanide contamination in an aquifer affected by ferrocyanide disposal from nuclear waste processing at the US Department of Energy’s Hanford Site in south-eastern Washington State (USA). We examined bacterial productivity and microbial cell density in groundwater (GW) from wells with varying levels of recent and historical total cyanide concentrations. We used tritiated leucine (3H-Leu) uptake as a proxy for heterotrophic, aerobic bacterial productivity in the GW, and we measured cell density via nucleic acid staining followed by epifluorescence microscopy. Bacterial productivity varied widely, both among wells that had high historical and recent total cyanide (CN−) concentrations and among wells that had low total CN− values. Standing microbial biomass varied less, and was generally greater than that observed in a similar study of uranium-contaminated hyporheic-zone groundwater at the Hanford Site. Our results showed no correlation between 3H-Leu uptake and recent or historical cyanide concentrations in the wells, consistent with what is known about cyanide toxicity with respect to iron speciation. However, additional sampling of the CN− affected groundwater, both in space and time, would be needed to confirm that the CN− contamination is not affecting the GW biota.
Abundant and Rare Bacterioplankton in Freshwater Lakes Subjected to Different Levels of Tourism Disturbances
Authors: Jiao Congcong , Zhao Dayong , Huang Rui , Cao Xinyi , Zeng Jin , Lin Yuqing , Zhao Wenjie
Published: August 2018

Anthropogenic disturbances have a negative impact on lake ecosystems, such as water environmental degradation. Bacterioplankton communities are essential components in lakes and consist of a few abundant species and several rare taxa. However, little is known about the community diversity and composition of abundant and rare bacterioplankton subjected to different levels of anthropogenic disturbances. In this study, water samples were collected from twelve freshwater lakes located around the city of Nanjing, China. Both Illumina MiSeq sequencing and multivariate statistical analysis were employed to determine the bacterioplankton community composition and its relation to environmental variables. The results indicated that tourism disturbances (mostly sewage discharge and tourist activities) altered the community structure of both abundant and rare bacterioplankton by changing water physicochemical characteristics. Alpha diversity of both abundant and rare taxa did not differ among different anthropogenic disturbance lakes (p > 0.05). Rare bacterial taxa possessed higher alpha diversity than abundant taxa, though rare taxa occupied a tiny portion of abundance (4.5%). Redundancy analysis demonstrated that dissolved organic carbon (DOC) was the most significant correlation variable for constraining the variation of abundant taxa, whereas total phosphorus (TP), ammonium nitrogen (NH4+-N), and chlorophyll-a (Chl-a) were the most dominant environmental factors constraining the rare taxa, indicating abundant and rare taxa may have different ecological niches.
Is Overgrazing Really Influencing Soil Erosion?
Authors: Nicu Ionut Cristi
Published: August 2018

Soil erosion is a serious problem spread over a variety of climatic areas around the world. The main purpose of this paper is to produce gully erosion susceptibility maps using different statistical models, such as frequency ratio (FR) and information value (IV), in a catchment from the northeastern part of Romania, covering a surface of 550 km2. In order to do so, a total number of 677 gullies were identified and randomly divided into training (80%) and validation (20%) datasets. In total, 10 conditioning factors were used to assess the gully susceptibility index (GSI); namely, elevation, precipitations, slope angle, curvature, lithology, drainage density, topographic wetness index, landforms, aspect, and distance from rivers. As a novelty, overgrazing was added as a conditioning factor. The final GSI maps were classified into four susceptibility classes: low, medium, high, and very high. In order to evaluate the two models prediction rate, the AUC (area under the curve) method was used. It has been observed that adding overgrazing as a contributing factor in calculating GSI does not considerably change the final output. Better predictability (0.87) and success rate (0.89) curves were obtained with the IV method, which proved to be more robust, unlike FR method, with 0.79 value for both predictability and success rate curves. When using sheepfolds, the value decreases by 0.01 in the case of the FR method, and by 0.02 in the case of the success rate curve for the IV method. However, this does not prove the fact that overgrazing is not influencing or accelerating soil erosion. A multi-temporal analysis of soil erosion is needed; this represents a future working hypothesis.
A Review of Demand Models for Water Systems in Buildings including a Bayesian Approach
Authors: Wong Ling-Tim , Mui Kwok-Wai
Published: August 2018

Instantaneous flow rate estimation is essential for sizing pipes and other components of water systems in buildings. Although various demand models have been developed in line with design and technology trends, most water supply system designs are routinely and substantially over-sized to keep failure risks to a minimum. Three major types of demand models from the literature are reviewed in this paper: (1) deterministic approach; (2) probabilistic approach; and (3) demand time-series approach. As findings show some widely used model estimates are much larger than the field measurements, this paper proposes a Bayesian approach to bridge the gap between model-based and field-measured values for the probable maximum simultaneous water demand. The proposed approach is flexible to adopt estimates as its prior values from a wide range of existing water demand models for determining the Bayesian coefficients for reference models, codes, and design standards with relevant measurement data. The approach provides a useful method not only for evaluating the corresponding demand values from various design references, but also for responding to the call for sustainable building design.
The High-velocity Stars in the Local Stellar Halo from Gaia and LAMOST
Authors: Du Cuihua , Li Hefan , Liu Shuai , Donlon Thomas , Newberg Heidi Jo
Published: August 2018

Based on the first Gaia data release and spectroscopy from the LAMOST Data Release 4, we study the kinematics and chemistry of the local halo stars. The halo stars are identified kinematically with a relative speed of at least 220 km s−1 with respect to the local standard of rest. In total, 436 halo stars are identified. From this halo sample, 16 high-velocity (HiVel) stars are identified. We studied the metallicity and [α/Fe] distribution of these HiVel stars. Though most HiVel stars are metal-poor, there are several stars that have metallicities above −0.5 dex. To understand the origin of high-velocity stars, we evolve the trajectory of the star backward along the orbit in our adopted Galaxy potential model to determine the orbital parameters and assess whether the star could have originated in the Galactic center (GC). We found that some high-velocity stars could have originated from the GC, but other stars were probably kicked up from the Galactic disk.
DAVs: Red Edge and Outbursts
Authors: Luan Jing , Goldreich Peter
Published: August 2018

As established by photometric surveys, white dwarfs with hydrogen atmospheres and surface gravity, log(g) ≈ 8.0 pulsate as they cool across the temperature range of 12,500 K ≳ T
eff ≳ 10,800 K. Known as DAVs or ZZ Ceti stars, their oscillations are attributed to gravity modes excited by convective driving. Overstability requires convective driving to exceed radiative damping. Previous works have demonstrated that ω ≳ max(τ

c

−1, L

ℓ,b
) is a necessary and sufficient condition for overstability. Here τ

c
and L

ℓ,b
are the effective thermal timescale and Lamb frequency at the base of the surface convection zone. Below the observational red edge, L

ℓ,b
 ≫ τ

c

−1, so overstable modes all have ωτ

c
 ≫ 1. Consequently, their photometric amplitudes are reduced by that large factor rendering them difficult to detect. Although proposed previously, the condition ω ≳ L

ℓ,b
has not been clearly interpreted. We show that modes with ω < L

ℓ,b
suffer enhanced radiative damping that exceeds convective driving rendering them damped. A quasi-adiabatic analysis is adequate to account for this enhancement. Although this approximation is only marginally valid at the red edge, it becomes increasingly accurate toward both higher and lower

. Recently, Kepler discovered a number of cool DAVs that exhibit sporadic flux outbursts. Typical outbursts last several hours, are separated by days, and release ∼1033–1034 erg. We attribute outbursts to limit cycles arising from sufficiently resonant 3-mode couplings between overstable parent modes and pairs of radiatively damped daughter modes. Limit cycles account for the durations and energies of outbursts and their prevalence near the red edge of the DAV instability strip.
Taxonomic review of the genus Dirrhagofarsus in Korea (Coleoptera, Eucnemidae)
Authors: Seung Jinbae , Muona Jyrki , Lee Seunghwan
Published: August 2018

The genusDirrhagofarsusis firstly recorded from Korea with three species:Dirrhagofarsuslewisi(Fleutiaux, 1900),Dirrhagofarsusmodestus(Fleutiaux, 1923), andDirrhagofarsusunicolor(Hisamatsu, 1960). A key to Korean species ofDirrhagofarsus, with diagnoses, redescriptions, and photographs of important structures is provided. In this work, Dirrhagusmodestusf.unicolor Hisamatsu, 1960 is regarded as a valid species,Dirrhagofarsusunicolor(Hisamatsu, 1960),comb. n.
Assessment of mycotoxin contamination in maize and wheat stored in silos using two sampling processes
Authors: Mallmann A.O. , Oliveira M.S. , Dilkin P. , Vidal J.K. , Meinerz G.R. , Almeida C.A.A. , Mallmann C.A.
Published: August 2018

Mycotoxin contamination of stored cereals often occurs in a highly heterogeneous manner, necessitating the use of representative sampling to minimise analytical errors. The objective of this study was to compare mycotoxin analysis in stored maize and wheat using two sampling processes. Samples were obtained from four maize silos and two wheat silos. A pneumatic probe was introduced in the centre and at the four central points of each quadrant, from the top to the bottom of the silo (12 m). For sampling process A, this was divided into three samples (upper third, middle third and lower third of the silo height). No sample subdivision took place for sampling process B. LC-MS/MS was used for analysis of aflatoxins (AF), fumonisins (FB), zearalenone (ZEA) and deoxynivalenol (DON) in maize and DON and ZEA in wheat. Sampling procedures were compared with respect to the variability of the collected data. AF, FB, ZEA and DON were detected in 77.5, 100.0, 56.7 and 0.0% of the maize samples, respectively, and the mean concentration differed significantly between silos. In wheat, 100.0 and 97.5% of the samples were contaminated with DON and ZEA, respectively, and there was no significantly difference in mean concentration between silos. There was no significant difference (P>0.05) in the coefficients of variation (CVs) of AF (54.9 and 58.6%), FB (19.4 and 27.3%) and ZEA (68.9 and 85.5%) between sampling processes A and B in maize silos. The DON CV in sampling process A (10.1%) was lower (P<0.05) than the CV in sampling process B (22.2%) in wheat silos. Overall, the two sampling processes provided analytical results with the same variability in maize and different variability for DON in wheat, where process A yielded results with lower variability.
A Discourse Analysis of Research Texts on Mumpreneurs
Authors: Surangi H. A. K. N. S. , Ranwala R. S.
Published: August 2018

Research investigating female entrepreneurs has developed considerably over the past two decades. However, the muprenurship concept is still a relatively under-researched area, and represents a challenging research field. Departing from a social constructionist understanding of mumpreneurs, this study examines how the entrepreneurial mothers are constructed in research articles. The paper makes use of discourse analysis to examine a selection of empirical research articles from 2000 to 2017 on mumpreneurs in entrepreneurship research in order to convey the key concept, main findings, key contribution, and the methodology. The analysis of the research texts revealed several assumptions and constructs that were taken for granted about mumpreneurs. Main findings based on the discourse analysis reveal five hegemonic statements: Mumpreneurs are not ‘proper’ entrepreneurs, many women face competing and often contradictory societal expectations when they are combining motherhood and business, entrepreneurship supporting motherhood, new entrepreneurial identity: ‘I am not just a housewife, and mumpreneurs’ motivations change over and the life course. The practices and the research results are moreover dependent on the particular context in which the articles are produced. This means that their results and assumptions cannot be generalized to other contexts uncritically.
Impaired Development and Expansion of Germinal Center Follicular Th Cells in Simian Immunodeficiency Virus–Infected Neonatal Macaques
Authors: Xu Huanbin , Ziani Widade , Shao Jiasheng , Doyle-Meyers Lara A. , Russell-Lodrigue Kasi E. , Ratterree Marion S. , Veazey Ronald S. , Wang Xiaolei
Published: August 2018

Germinal center (GC) CD4+ follicular Th (Tfh) cells are critical for cognate B cell help in humoral immune responses to pathogenic infections. Although Tfh cells are expanded or depleted in HIV/SIV-infected adults, the effects of pediatric HIV/SIV infection on Tfh cells remain unclear. In this study, we examined changes in lymphoid follicle formation in lymph nodes focusing on GC Tfh cells, B cell development, and differentiation in SIV-infected neonatal rhesus macaques (Macaca mulatta) compared with age-matched cohorts. Our data showed that follicles and GCs of normal infants rapidly formed in the first few weeks of age, in parallel with increasing GC Tfh cells in various lymphoid tissues. In contrast, GC development and GC Tfh cells were markedly impaired in SIV-infected infants. There was a very low frequency of GC Tfh cells throughout SIV infection in neonates and subsequent infants, accompanied by high viremia, reduction of B cell proliferation/resting memory B cells, and displayed proinflammatory unresponsiveness. These findings indicate neonatal HIV/SIV infection compromises the development of GC Tfh cells, likely contributing to ineffective Ab responses, high viremia, and eventually rapid disease progression to AIDS.
Engineering a Single-Agent Cytokine/Antibody Fusion That Selectively Expands Regulatory T Cells for Autoimmune Disease Therapy
Authors: Spangler Jamie B. , Trotta Eleonora , Tomala Jakub , Peck Ariana , Young Tracy A. , Savvides Christina S. , Silveria Stephanie , Votavova Petra , Salafsky Joshua , Pande Vijay S. , Kovar Marek , Bluestone Jeffrey A. , Garcia K. Christopher
Published: August 2018

IL-2 has been used to treat diseases ranging from cancer to autoimmune disorders, but its concurrent immunostimulatory and immunosuppressive effects hinder efficacy. IL-2 orchestrates immune cell function through activation of a high-affinity heterotrimeric receptor (composed of IL-2Rα, IL-2Rβ, and common γ [γc]). IL-2Rα, which is highly expressed on regulatory T (TReg) cells, regulates IL-2 sensitivity. Previous studies have shown that complexation of IL-2 with the JES6-1 Ab preferentially biases cytokine activity toward TReg cells through a unique mechanism whereby IL-2 is exchanged from the Ab to IL-2Rα. However, clinical adoption of a mixed Ab/cytokine complex regimen is limited by stoichiometry and stability concerns. In this study, through structure-guided design, we engineered a single agent fusion of the IL-2 cytokine and JES6-1 Ab that, despite being covalently linked, preserves IL-2 exchange, selectively stimulating TReg expansion and exhibiting superior disease control to the mixed IL-2/JES6-1 complex in a mouse colitis model. These studies provide an engineering blueprint for resolving a major barrier to the implementation of functionally similar IL-2/Ab complexes for treatment of human disease.
SAMHD1 Posttranscriptionally Controls the Expression of Foxp3 and Helios in Human T Regulatory Cells
Authors: Kim Yong Chan , Kim Kee Kwang , Yoon Jeongheon , Scott David W. , Shevach Ethan M.
Published: August 2018

Clinical application of Ag-specific T regulatory cells (Tregs) offers promise for the treatment of undesirable immune diseases. To achieve this goal, long-term expansion of Tregs is required to obtain sufficient numbers of cells. However, human Tregs are not stable ex vivo. Therefore, we previously developed an innovative Treg expansion protocol using 25mer-phosphorothioated random oligonucleotides (ODNps25). The addition of ODNps25 successfully resulted in the stabilization of engineered Ag-specific Tregs; however, the mechanism is not fully characterized. We first identified sterile α motif histidine-aspartate–domain containing protein 1 (SAMHD1) as an ODNps25-binding protein using a UV–cross-linking pull-down strategy. SAMHD1 physically interacted with the 3′ untranslated region of Foxp3 mRNA and was translocated from nucleus to cytoplasm after ODNps25 treatment. Importantly, addition of ODNps25 enhanced the interaction of SAMHD1 and Foxp3 mRNA significantly, and this interaction was increased by TCR stimulation. Because ODNps25 binds to the nuclease (HD) domain of SAMHD1, we then established that overexpression of a dNTPase-deficient mutant (D137N) in Tregs significantly stabilized the expression level of the Foxp3 protein. Furthermore, we found that TCR stimulation upregulates phosphorylation of the threonine residue (Thr592), which is a regulatory site to control SAMHD1 activity, and phosphorylation of Thr592 is critical to control SAMHD1 activity to stabilize the expression of Foxp3 and Helios in Tregs. Taken together, we suggest that the interaction of ODNPs25 in HD or phosphorylation of Thr592 by TCR stimulation interferes with nuclease activity of SAMHD1, thereby stabilizing 3′ untranslated region of Foxp3 and Helios mRNAs in long-term culture.
Effect of Thiosulfate on Pitting Corrosion of Ni-Cr-Fe Alloys in Chloride Solutions
Authors: Becerra Araneda Abraham A. , Kappes Mariano A. , Rodríguez Martín A. , Carranza Ricardo M.
Published: August 2018

Pitting corrosion of Alloys 600, 690, and 800 (UNS N06600, N06690, and N08800) was studied in 1 M NaCl solution with different concentrations of thiosulfate (). Alloys exhibited vastly different electrochemical behavior, depending on the concentration and chromium content of the alloy. Alloy 600 exhibited a breakdown and repassivation potential that decreased with decreasing concentration, in the range from 1 M to 10−4 M. Breakdown and repassivation potentials decreased about 300 mV and 600 mV, respectively, when 10−4 M was added to a 1 M NaCl solution. For Alloys 690 and 800, additions of in the range of 1 M to 0.01 M caused a decrease in the breakdown and repassivation potentials. Dilute solutions were more aggressive, and a 0.01 M addition of to a 1 M NaCl solution caused a decrease in breakdown and repassivation potentials of about 300 mV. In a solution containing 0.001 M Na2S2O3 + 1 M NaCl, Alloys 690 and 800 showed two different submodes of pitting, each one of them existing at a different range of potential. Chloride pitting corrosion was observed at high potentials and was characterized by pits with a lacy cover. The stable pit initiation potential associated with this process in both alloys was near 300 mVAg/AgCl and was preceded by frequent metastable events. Chloride plus pitting was observed at low potentials (near −225 mVAg/AgCl) and was characterized by hemispherical pits. In potentiodynamic curves, this submode of pitting showed a characteristic anodic peak of approximately 120 mV width and a maximum current density of 10 μA/cm2 for both alloys. Potentiostatic tests at potentials within this anodic peak led to stable pit growth. Those pits could be repassivated by scanning the potential either in noble or active directions. Low-potential and high-potential pitting submodes were separated by a stable passivity range, as determined by potentiodynamic curves. Upon a further decrease in concentration down to 10−4 M, only high-potential pitting corrosion was observed, with pitting and repassivation potentials similar than those in 1 M NaCl solution.
Intra-annual variations of regional aerosol optical depth, vertical distribution, and particle types from multiple satellite and ground-based observational datasets
Authors: Zhao Bin , Jiang Jonathan H. , Diner David J. , Su Hui , Gu Yu , Liou Kuo-Nan , Jiang Zhe , Huang Lei , Takano Yoshi , Fan Xuehua , Omar Ali H.
Published: August 2018

Abstract. The climatic and health effects of aerosols are strongly dependent on the
intra-annual variations in their loading and properties. While the seasonal
variations of regional aerosol optical depth (AOD) have been extensively
studied, understanding the temporal variations in aerosol vertical
distribution and particle types is also important for an accurate estimate of
aerosol climatic effects. In this paper, we combine the observations from
four satellite-borne sensors and several ground-based networks to investigate
the seasonal variations of aerosol column loading, vertical distribution, and
particle types over three populous regions: the Eastern United States (EUS),
Western Europe (WEU), and Eastern and Central China (ECC). In all three
regions, column AOD, as well as AOD at heights above 800 m, peaks in
summer/spring, probably due to accelerated formation of secondary aerosols
and hygroscopic growth. In contrast, AOD below 800 m peaks in winter over
WEU and ECC regions because more aerosols are confined to lower heights due
to the weaker vertical mixing. In the EUS region, AOD below 800 m shows two
maximums, one in summer and the other in winter. The temporal trends in
low-level AOD are consistent with those in surface fine particle
(PM2.5) concentrations. AOD due
to fine particles (<0.7 µm diameter) is much larger in
spring/summer than in winter over all three regions. However, the coarse mode
AOD (>1.4 µm diameter), generally shows small variability,
except that a peak occurs in spring in the ECC region due to the prevalence
of airborne dust during this season. When aerosols are classified according
to sources, the dominant type is associated with anthropogenic air pollution,
which has a similar seasonal pattern as total AOD. Dust and sea-spray
aerosols in the WEU region peak in summer and winter, respectively, but do
not show an obvious seasonal pattern in the EUS region. Smoke aerosols, as
well as absorbing aerosols, present an obvious unimodal distribution with a
maximum occurring in summer over the EUS and WEU regions, whereas they follow
a bimodal distribution with peaks in August and March (due to crop residue
burning) over the ECC region.