bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of a parallel‐plate RF probe for high resolution thin film imaging
Authors: Ramírez Aguilera Andrés , MacMillan Bryce , Goward Gillian R. , Balcom Bruce J. 
Published: December 2018

AbstractChoosing an MR probe with the correct dimensions and high sensitivity is critical for magnetic resonance imaging, especially high resolution thin film imaging. In this work, a parallel‐plate resonator has been optimized for strength and uniformity of the B1 magnetic field. The parallel‐plate resonator is designed for high resolution imaging in the direction perpendicular to the plates. The optimization process was undertaken through simulation with CST Micro Wave Studio, followed by experiment. A 400 μm capillary tube, filled with doped water, was used for testing the optimized probe in a 2.4 T magnet. It is shown that increasing the width of the copper leads connected to the plates increases the homogeneity of the B1 magnetic field by almost 90%. The best approach to increase the sensitivity and the homogeneity of the probe was to maintain the dimensions of the plates and copper leads but to add additional capacitors at the corners to distribute the current. This approach produces a 40% stronger B1 magnetic field and increases the homogeneity by almost 85%. The experimental B1 magnetic field of the parallel‐plate prototype agrees within 20% of the value found through simulation, for specified power. The experimental MRI results show that it is possible to achieve a nominal resolution of 10 μm between the plates for suitable samples using the optimized probe. The optimized parallel‐plate resonator, combined with a phase encode SE SPI method, may be used for high resolution studies of lithium‐ion transport in the electrolyte solution of lithium‐ion batteries.
Differential investment in brain regions for a diurnal and nocturnal lifestyle in Australian Myrmecia ants
Authors: Sheehan Zachary B. V. , Kamhi J. Frances , Seid Marc A. , Narendra Ajay 
Published: December 2018

AbstractAnimals are active at different times of the day. Each temporal niche offers a unique light environment, which affects the quality of the available visual information. To access reliable visual signals in dim‐light environments, insects have evolved several visual adaptations to enhance their optical sensitivity. The extent to which these adaptations reflect on the sensory processing and integration capabilities within the brain of a nocturnal insect is unknown. To address this, we analyzed brain organization in congeneric species of the Australian bull ant, Myrmecia, that rely predominantly on visual information and range from being strictly diurnal to strictly nocturnal. Weighing brains and optic lobes of seven Myrmecia species, showed that after controlling for body mass, the brain mass was not significantly different between diurnal and nocturnal ants. However, the optic lobe mass, after controlling for central brain mass, differed between day‐ and night‐active ants. Detailed volumetric analyses showed that the nocturnal ants invested relatively less in the primary visual processing regions but relatively more in both the primary olfactory processing regions and in the integration centers of visual and olfactory sensory information. We discuss how the temporal niche occupied by each species may affect cognitive demands, thus shaping brain organization among insects active in dim‐light conditions.
Characterization of perinatally born glutamatergic neurons of the mouse olfactory bulb based on NeuroD6 expression reveals their resistance to sensory deprivation
Authors: Angelova Alexandra , Platel Jean‐Claude , Béclin Christophe , Cremer Harold , Coré Nathalie 
Published: December 2018

AbstractDuring postnatal olfactory bulb (OB) neurogenesis, predetermined stem cells residing in the ventricular–subventricular zone continuously generate progenitors that migrate in the rostral migratory stream and integrate into the OB. Although the vast majority of these postnatally generated interneurons are inhibitory, a sub‐fraction represents glutamatergic neurons that integrate into the superficial glomerular layer. In the present work, we demonstrate that the bHLH transcription factor NeuroD6 is specifically and transitorily expressed in the dorsal neurogenic lineage that generates glutamatergic juxtaglomerular cells (JGCs) for the OB. Using lineage tracing combined with whole brain clearing, we provide new insight into timing of generation, morphology, and connectivity of glutamatergic JGCs. Specifically, we show that all glutamatergic JGCs send complex axons with varying projection patterns into different layers of the OB. Moreover, we find that, contrary to GABAergic OB interneurons, glutamatergic JGCs survive under sensory deprivation, indicating that inhibitory and excitatory populations are differentially susceptible to environmental stimulation.
Sparse data encoder and decoder to improve security in video steganography
Authors: Perumal Kaliram , Muthusamy Suganthi , Gengavel Gowrison 
Published: December 2018

SummarySteganography is a technological art to hide text, audio, digital image,s and videos in secret communication, and in the past decade, much research has been carried out the respective field. Currently, secret communications through video steganography are focused on numerous applications due to emerge of social communication networks such as whatsApp, twitter, and Facebook. In video‐based steganography, the video with any format have been separated into number of frames associated to the dividing speed and select few frames for embedding purpose. The existing video steganography techniques have some advantages and limitations in information hiding and so to design a well‐intentioned steganography algorithm for improving security and robustness are significant task. The experimental results show that the proposed block‐based transform domain sparse data encoder and decoder video steganography method provide high security with improved PSNR.
The new Multicast Repair (M‐REP) IP fast reroute mechanism
Authors: Papan Jozef , Segec Pavel , Paluch Peter , Uramova Jana , Moravcik Marek 
Published: December 2018

SummaryThe network convergence time may take hundreds of milliseconds or more. Since this repair performance may be unsatisfactory, IP fast reroute (IPFRR) approaches have been developed to decrease the network convergence time and minimize traffic loss. These IPFRR mechanisms are usually based on the proactive precomputation of a backup path before a failure occurs. Once a failure is detected, the router running IPFRR will immediately use this backup path in response to the failure, rather than computing a replacement path only after a failure has occurred. The computation of an alternative path in many IPFRR mechanisms requires that the computing node (router) knows the exact network topology. In this paper, we present a new IPFRR mechanism called the multicast repair (M‐REP) IPFRR mechanism, which provides an advanced fast reroute technique for Internet service providers‘ (ISP‘s) core networks. The M‐REP IPFRR mechanism is based on IP multicast and utilizes Protocol Independent Multicast – Dense Mode (PIM‐DM) with the modification of an internal reverse path forwarding (RPF) check. The M‐REP IPFRR mechanism does not depend on any particular routing protocol type (distance‐vector or link‐state) and requires less system resources because of its precomputation‐less character but still provides immediate reaction to failure.
The optimization of virtual resource allocation in cloud computing based on RBPSO
Authors: Wang Xiaohui , Gu Haoran , Yue YuXian 
Published: December 2018

SummaryThe virtual resource allocation in cloud computing is becoming a critical issue. In order to meet the task requirements of different users, virtual machines need to be placed on physical machines through virtualization technology in the data center. However, in this process, the total load balance, energy consumption, and resource utilization of physical machines should be considered. Therefore, two models are established for two different optimization targets, respectively. The first model is built to minimize the degree of load imbalance. The second model is built to maximize the resource utilization and minimize the energy consumption. To gain better results of virtual machines placement, we propose a new algorithm called resampled binary particle swarm optimization (RBPSO). To enhance the global search ability of BPSO, we add the re‐sampling, mutation and small vibration process to it, named RBPSO, for the purpose of maintaining the diversity of the population, reducing redundant calculation and thereby improving the ability and efficiency of the algorithm. Then, the RBPSO is used to solve the deployment problem of virtual machines in cloud computing. The experiments show that the proposed model is reasonable and RBPSO performs better than BPSO and genetic algorithm (GA).
Query expansion using named entity disambiguation for a question‐answering system
Authors: Kandasamy Saravanakumar , Cherukuri Aswani Kumar 
Published: December 2018

SummaryDue to the exponential growth in the size of available data, people often prefer direct answers in many cases, instead of a set of ranked documents while searching using a search engine. Furthermore, people often do not provide enough information regarding their search. Query expansion would help in such cases so that queries would be best understood by search engines. Although the queries are expanded, many a times, they end up with wrong results due to the entity mentions in the questions. Hence, we need to disambiguate named entities properly so as to choose the right mention. In this paper, a method is proposed for named entity disambiguation in order to help in query expansion. An adapted Lesk similarity measure is used to find the similarity between questions and the target Wikipedia disambiguation pages. The proposed approach has shown very good results in disambiguating organization‐ and miscellaneous‐type entity mentions.
Bidirectional compressive sensing for classification of gene expression data
Authors: Xu Xiaohua , Fan Baichuan , He Ping , Liang Yali , Ding Jie , Lou Yuan , Zhang Zhijun , Chang Xincheng 
Published: December 2018

SummaryThe classification of gene expression data is significantly important for medical diagnosis. In recent years, compressive sensing emerges as a popular sparse learning method and has been applied in different areas. It is featured with the sparse representation of data with a few atoms in the dictionary. However, the traditional compressive sensing model only focuses on the relationship among different samples but neglects the relationship among different genes. In order to take into account of the both kinds of correlation, we propose a novel bidirectional compressive sensing model for the classification of gene expression data. Under this model, we develop a novel Bi‐ADMM algorithm with three different variants to solve the optimization problem. The promising experimental results on the real‐world gene expression datasets demonstrate both the effectiveness and efficiency of our proposed approach.
Do corporate social responsibility ratings affect credit default swap spreads?
Authors: Drago Danilo , Carnevale Concetta , Gallo Raffaele 
Published: December 2018

AbstractWe examine the impact of a corporate social responsibility (CSR) rating announcement on the credit default swap (CDS) spreads of European firms. Our results indicate that a CSR rating upgrade leads to an immediate and significant decrease in CDS spreads of rated firms. In contrast, CSR rating downgrades do not have a significant immediate impact on the CDS market. Additionally, better CSR ratings, in terms of both the overall score and the scores for the three main CSR pillars (economic, environmental, and social), lead to lower CDS spreads. Therefore, we document that the CSR rating is a measure of CSR performance that affects market CDS prices. Our findings are consistent with the risk mitigation view, highlighting the benefits derived from CSR commitment. Consequently, CSR engagement can function as a tool for improving firm's creditworthiness. This result may provide an incentive to pay more attention to CSR in managerial, regulatory, and investment decisions.
Refining the Limits of Borderline Lymphoproliferative Disorders
Authors: Sorigue Marc , Raya Minerva , Vergara Sara , Sarrate Edurne , Orna Elisa , Juncà Jordi 
Published: December 2018

BackgroundThe concept of borderline lymphoproliferative disorder (LPD) has not been clearly defined.MethodsThis study aimed to classify patients with leukemic LPD (n = 597, excluding hairy cell leukemia, mantle cell lymphomas, and CD10‐positive LPDs) into CLL or non‐CLL applying three diagnostic strategies (the D'Arena and CLLflow scores and CD43 expression) and to better characterize unclassified patients.ResultsPatients with concurring CLL‐like (n = 441) or non‐CLL like (n = 99) results with the three diagnostic strategies were determined to have CLL and non‐CLL, respectively. Patients with discordant results (n = 57) were analyzed taking into consideration each individual cytometric marker and cytogenetic data: 41 were classified (11 CLL, 30 non‐CLL) and 16 (2.7% of the entire series) could not and were considered borderline LPD. Excluding borderline LPD, the CLLflow score had the highest accuracy of the three strategies. With the addition of CD43 no patient was misclassified. With the aid of hierarchical clustering, 12 of the 16 borderline patients seemed to fall into two well‐defined antigenic groups. None of the diagnostic strategies could reliably pick out borderline LPD.ConclusionThe combination of the CLLflow score and CD43 generally has a high diagnostic accuracy for leukemic LPD but it is not reliable to identify or diagnose borderline LPD. This latter group needs further study to determine its underlying biology. © 2018 International Clinical Cytometry Society
Combining capture–recapture data and known ages allows estimation of age‐dependent survival rates
Authors: Bird Tomas , Lyon Jarod , Wotherspoon Simon , Todd Charles , Tonkin Zeb , McCarthy Michael 
Published: December 2018

AbstractIn many animal populations, demographic parameters such as survival and recruitment vary markedly with age, as do parameters related to sampling, such as capture probability. Failing to account for such variation can result in biased estimates of population‐level rates. However, estimating age‐dependent survival rates can be challenging because ages of individuals are rarely known unless tagging is done at birth. For many species, it is possible to infer age based on size. In capture–recapture studies of such species, it is possible to use a growth model to infer the age at first capture of individuals. We show how to build estimates of age‐dependent survival into a capture–mark–recapture model based on data obtained in a capture–recapture study. We first show how estimates of age based on length increments closely match those based on definitive aging methods. In simulated analyses, we show that both individual ages and age‐dependent survival rates estimated from simulated data closely match true values. With our approach, we are able to estimate the age‐specific apparent survival rates of Murray and trout cod in the Murray River, Australia. Our model structure provides a flexible framework within which to investigate various aspects of how survival varies with age and will have extensions within a wide range of ecological studies of animals where age can be estimated based on size.
The influence of distance to perennial surface water on ant communities in Mopane woodlands, northern Botswana
Authors: Dalerum Fredrik , Retief Tarryn Anne , Havemann Carl Peter , Chimimba Christian T. , Janse van Rensburg Berndt 
Published: December 2018

AbstractStudies of biodiversity along environmental gradients provide information on how ecological communities change in response to biotic and abiotic factors. For instance, distance to water is associated with several factors that shape the structure and the functioning of ecosystems at a range of spatial scales. We investigated the influence of distance to a perennial water source on ant communities in a semi‐arid savanna in northern Botswana. Ant abundance, taxonomic richness, and both alpha and beta diversity were generally higher during the wet than the dry season. However, there were strong seasonal influences on the effects of distance to water, with more pronounced effects during the wet season. While both abundance and beta diversity declined with increasing distances to water during the wet season, there was a contrasting increase in alpha diversity. There was no major effect of distance to water on taxonomic richness during either season. Beta diversity was as high across as along gradients, and we found support for modular rather than nested community structures along gradients. Our study demonstrated that small‐scale gradients in distance to water can influence several aspects of ant communities in semi‐arid savannas. However, our results also point to strong effects of small‐scale environmental variation, for instance associated with vegetation characteristics, soil properties, and plant community structure that are not directly linked to water access.
Male immigration triggers increased growth in subordinate female meerkats
Authors: Dubuc Constance , Clutton‐Brock Tim H. 
Published: December 2018

AbstractThere is increasing evidence that some vertebrates can adjust their growth rate in relation to changes in the social context that affect their probability of breeding. Here, we show that, in meerkats (Suricata suricatta), which are singular cooperative breeders, subordinate females increase in body mass after their father is replaced as the dominant male in their natal group by an immigrant male, giving them regular access to an unfamiliar and unrelated mating partner, while their brothers showed no similar increase nor did subordinate females living in other stable groups (where male immigration did not occur did) in this time period. Moreover, subordinate females showed a greater increase in growth rate when their father was succeeded by an unfamiliar immigrant male than when he was replaced by a familiar male who was already resident. These results suggest that female meerkats can adjust their rate of growth to changes in the kinship composition of their groups that provide them with increased access to unrelated breeding partners, which may occur in other mammals as well when breeding opportunities change.
Optimal haemodynamics during left ventricular assist device support are associated with reduced haemocompatibility‐related adverse events
Authors: Imamura Teruhiko , Nguyen Ann , Kim Gene , Raikhelkar Jayant , Sarswat Nitasha , Kalantari Sara , Smith Bryan , Juricek Colleen , Rodgers Daniel , Ota Takeyoshi , Song Tae , Jeevanandam Valluvan , Sayer Gabriel , Uriel Nir 
Published: December 2018

AimsLeft ventricular assist device (LVAD) therapy improves the haemodynamics of advanced heart failure patients. However, it is unknown whether haemodynamic optimization improves haemocompatibility‐related adverse events (HRAEs). This study aimed to assess HRAEs in patients with optimized haemodynamics.Methods and resultsEighty‐three outpatients [aged 61 (53–67) years, 50 male] underwent a haemodynamic ramp test at 253 (95–652) days after LVAD implantation, and 51 (61%) had optimized haemodynamics (defined as central venous pressure < 12 mmHg, pulmonary artery wedge pressure < 18 mmHg, cardiac index > 2.2 L/min/m2) following LVAD speed adjustment. One‐year survival free of any HRAEs (non‐surgical bleeding, thromboembolic event, pump thrombosis, or neurological event) was achieved in 75% of the optimized group and in 44% of the non‐optimized group (hazard ratio 0.36, 95% confidence interval 0.18–0.73, P = 0.003). The net haemocompatibility score, using four escalating tiers of hierarchal severity to derive a total score for events, was significantly lower in the optimized group than the non‐optimized group (1.02 vs. 2.00 points/patient; incidence rate ratio 0.51, 95% confidence interval 0.29–0.90, P = 0.021).ConclusionLeft ventricular assist device patients in whom haemodynamics can be optimized had greater freedom from HRAEs compared to those without optimized haemodynamics.
Inkjet‐Printed Mesoporous TiO2 and Perovskite Layers for High Efficiency Perovskite Solar Cells
Authors: Huckaba Aron J. , Lee Yonghui , Xia Rui , Paek Sanghyun , Bassetto Victor Costa , Oveisi Emad , Lesch Andreas , Kinge Sachin , Dyson Paul J. , Girault Hubert , Nazeeruddin Mohammad Khaja 
Published: December 2018

AbstractPerovskite solar cells with mesoporous TiO2 electron transport layers have previously reached >22 % efficiency at the laboratory scale (<1 cm2), however, these layers are fabricated using spin‐coating, which is not conducive to large‐scale or high throughput fabrication. This report describes the inkjet printing of open‐pore mesoporous TiO2 thin films, perovskite thin films, and the fabrication of highly efficient perovskite solar cells using these films. Ink formulation and characterization studies, inkjet deposition optimization trials, film characterization, and comparison to spin‐coated layers are described. The printed TiO2 films exhibited an open‐pore morphology and homogeneous surface coverage in films ranging from 1 mm2 to >10 cm2. Perovskite solar cells with printed and pristine (un‐doped) inkjet‐printed TiO2 layers yielded efficiencies of 18.29 %, which were found to outperform cells made with spin‐coated and pristine TiO2 layers (16.91 %). When a quadruple‐cation perovskite absorber containing Cs, formamidinium, methylammonium, and guanidinium was deposited by inkjet‐printing onto the inkjet‐printed TiO2 layer, nearly 12 % average efficiency was reached, with the champion cell reaching 14.11 %. This absorber exhibited higher efficiency and stability than did inkjet‐printed MAPbI3 films deposited on the inkjet‐printed TiO2 film.
Moving least squares reconstruction for sharp interface immersed boundary methods
Authors: Haji Mohammadi M. , Sotiropoulos F. , Brinkerhoff J. 
Published: December 2018

SummaryWe propose a new approach for reconstructing velocity boundary conditions in sharp‐inerface immersed boundary (IB) methods based on the moving least squares (MLS) interpolation method. The MLS is employed to not only reconstruct velocity boundary conditions but also to calculate the pressure and velocity gradients in the vicinity of the immersed body, which are required in fluid structure interaction problems to obtain the force exerted by the fluid on the structure. To extend the method to arbitrarily complex geometries with nonconvex shaped boundaries, the visibility method is combined with the MLS method. The performance of the proposed curvilinear IB MLS (CURVIB‐MLS) is demonstrated by systematic grid‐refinement studies for two‐ and three‐dimensional tests and compared with the standard CURVIB method employing standard wall‐normal interpolation for reconstructing boundary conditions. The test problems are flow in a lid‐driven cavity with a sphere, uniform flow over a sphere, flow on a NACA0018 airfoil at incidence, and vortex‐induced vibration of an elastically‐mounted cylinder. We show that the CURVIB‐MLS formulation yields a method that is easier to implement in complex geometries and exhibits higher accuracy and rate of convergence relative to the standard CURVIB method. The MLS approach is also shown to dramatically improve the accuracy of calculating the pressure and viscous forces imparted by the flow on the body and improve the overall accuracy of FSI simulations. Finally, the CURVIB‐MLS approach is able to qualitatively capture on relatively coarse grids important features of complex separated flows that the standard CURVIB method is able to capture only on finer grids.