bluuebunny/crossref_metadata_2025_split huggingface dataset:
Challenges and Opportunities in Magnetospheric Space Weather Prediction
Authors: Morley S. K. 
Published: December 2019

AbstractSpace Weather is the study of the dynamics of the coupled Solar‐Terrestrial environment, as these dynamics impact technological systems and human activity. This paper reviews a selection of the advances, challenges, and new opportunities for magnetospheric space weather, and while the focus is on specific phenomena, many other aspects of space weather will have similar challenges and needs. As a scientific field with direct applications, the field of space weather is partly driven by imperatives from both policy and operations. We provide an introduction to some of the context in which the field exists and discuss how this might shape future developments and norms within the space weather enterprise. We briefly examine benchmarking, as a policy and operationally driven activity, as it provides immediate societal relevance and an opportunity to stretch scientific understanding. As numerical space weather prediction now becomes routine, and exascale computing is in the near future, we identify challenges relating to computational expense and big data, capturing and accounting for uncertainties, and specification of boundary conditions. Here, as with the observations supporting numerical space weather prediction, the key challenge lies in extending the lead time of predictions. We also discuss the role of data, particularly in regard to model validation and empirical modeling. Due to the growing societal impact of space weather, we also examine the relationships between space weather and its terrestrial counterpart and look at the importance of continuous evaluation, monitoring progress in predictive capability, and communication with researchers, forecasters, and end users.
Characterizing the temporal Dynamics of Melatonin and Cortisol Changes in Response to Nocturnal Light Exposure
Authors: Rahman Shadab A. , Wright Kenneth P. , Lockley Steven W. , Czeisler Charles A. , Gronfier Claude 
Published: December 2019

AbstractWe studied the dynamics of melatonin suppression and changes in cortisol levels in humans in response to light exposure at night using high-frequency blood sampling. Twenty-one young healthy participants were randomized to receive either intermittent bright (~9,500 lux) light (IBL), continuous bright light (CBL) or continuous dim (~1 lux) light (VDL) for 6.5 h during the biological night (n = 7 per condition). Melatonin suppression occurred rapidly within the first 5 min and continued until the end of each IBL stimuli (t1/2 = ~13 min). Melatonin recovery occurred more slowly between IBL stimuli (half-maximal recovery rate of ~46 min). Mean melatonin suppression (~40%) and recovery (~50%) were similar across IBL stimuli. Suppression dynamics under CBL were also rapid (t1/2 = ~18 min), with no recovery until the light exposure ended. There was a significant linear increase of cortisol levels between the start and end of each IBL stimulus. Under CBL conditions cortisol showed trimodal changes with an initial linear activating phase, followed by an exponential inhibitory phase, and a final exponential recovery phase. These results show that light exposure at night affects circadian driven hormones differently and that outcomes are influenced by the duration and pattern of light exposure.
Four hundred years of cork imaging: New advances in the characterization of the cork structure
Authors: Crouvisier-Urion Kevin , Chanut Julie , Lagorce Aurélie , Winckler Pascale , Wang Zi , Verboven Pieter , Nicolai Bart , Lherminier Jeannine , Ferret Eric , Gougeon Régis D. , Bellat Jean-Pierre , Karbowiak Thomas 
Published: December 2019

AbstractIn 1665, Robert Hooke was the first to observe cork cells and their characteristic hexagonal shape, using the first optical microscope, which was invented by him at that time. With the evolution of imaging techniques, the structure of cork has been analysed with greater accuracy over time. This work presents the latest advances in the characterization of this unique material through a multiscale approach. Such investigation brings new insight into the architecture of cork, particularly the differences between the cells of the phellem and those bordering the lenticels. In the latter case, cell differentiation from the lenticular phellogen was restricted to one cell layer, which leads to a cell wall that is 10 times thicker for lenticels. They also displayed a different chemical composition because of unsuberization and a high lignin content in lenticels. Such advances in the knowledge of the structure and composition of cork cells contributes to a better understanding of the macroporosity of cork, down to the nanoscale.
Tumor-suppressing potential of stingless bee propolis in in vitro and in vivo models of differentiated-type gastric adenocarcinoma
Authors: Desamero Mark Joseph , Kakuta Shigeru , Tang Yulan , Chambers James Kenn , Uchida Kazuyuki , Estacio Maria Amelita , Cervancia Cleofas , Kominami Yuri , Ushio Hideki , Nakayama Jun , Nakayama Hiroyuki , Kyuwa Shigeru 
Published: December 2019

AbstractThe protective property of propolis across a wide spectrum of diseases has long been realized, yet the anti-tumor efficacy of this bioactive substance from Philippine stingless bees has remained poorly understood. Here, we showed the tumor-suppressing potential of crude ethanolic extract of Philippine stingless bee propolis (EEP) in in vitro models of gastric cancer highlighting the first indication of remarkable subtype specificity towards differentiated-type human gastric cancer cell lines but not the diffuse-type. Mechanistically, this involved the profound modulation of several cell cycle related gene transcripts, which correlated with the prominent cell cycle arrest at the G0/G1 phase. To reinforce our data, a unique differentiated-type gastric cancer model, A4gnt KO mice, together with age-matched 60 week-old C57BL/6 J mice were randomly assigned to treatment groups receiving distilled water or EEP for 30 consecutive days. EEP treatment induced significant regression of gross and histological lesions of gastric pyloric tumors that consistently corresponded with specific transcriptional regulation of cell cycle components. Also, the considerable p21 protein expression coupled with a marked reduction in rapidly dividing BrdU-labeled S-phase cells unequivocally supported our observation. Altogether, these findings support the role of Philippine stingless bee propolis as a promising adjunct treatment option in differentiated-type gastric cancer.
Identification of clinical and urine biomarkers for uncomplicated urinary tract infection using machine learning algorithms
Authors: Gadalla Amal A. H. , Friberg Ida M. , Kift-Morgan Ann , Zhang Jingjing , Eberl Matthias , Topley Nicholas , Weeks Ian , Cuff Simone , Wootton Mandy , Gal Micaela , Parekh Gita , Davis Paul , Gregory Clive , Hood Kerenza , Hughes Kathryn , Butler Christopher , Francis Nick A. 
Published: December 2019

AbstractWomen with uncomplicated urinary tract infection (UTI) symptoms are commonly treated with empirical antibiotics, resulting in overuse of antibiotics, which promotes antimicrobial resistance. Available diagnostic tools are either not cost-effective or diagnostically sub-optimal. Here, we identified clinical and urinary immunological predictors for UTI diagnosis. We explored 17 clinical and 42 immunological potential predictors for bacterial culture among women with uncomplicated UTI symptoms using random forest or support vector machine coupled with recursive feature elimination. Urine cloudiness was the best performing clinical predictor to rule out (negative likelihood ratio [LR−] = 0.4) and rule in (LR+ = 2.6) UTI. Using a more discriminatory scale to assess cloudiness (turbidity) increased the accuracy of UTI prediction further (LR+ = 4.4). Urinary levels of MMP9, NGAL, CXCL8 and IL-1β together had a higher LR+ (6.1) and similar LR− (0.4), compared to cloudiness. Varying the bacterial count thresholds for urine culture positivity did not alter best clinical predictor selection, but did affect the number of immunological predictors required for reaching an optimal prediction. We conclude that urine cloudiness is particularly helpful in ruling out negative UTI cases. The identified urinary biomarkers could be used to develop a point of care test for UTI but require further validation.
Boundary integral equation method for resonances in gradient index cavities designed by conformal transformation optics
Authors: Ryu Jung-Wan , Cho Jinhang , Lee Soo-Young , Kim Yushin , Park Sang-Jun , Rim Sunghwan , Choi Muhan , Kim Inbo 
Published: December 2019

AbstractIn the case of two-dimensional gradient index cavities designed by the conformal transformation optics, we propose a boundary integral equation method for the calculation of resonant mode functions by employing a fictitious space which is reciprocally equivalent to the physical space. Using the Green’s function of the interior region of the uniform index cavity in the fictitious space, resonant mode functions and their far-field distributions in the physical space can be obtained. As a verification, resonant modes in limaçon-shaped transformation cavities were calculated and mode patterns and far-field intensity distributions were compared with those of the same modes obtained from the finite element method.
LEGO® Block Structures as a Sub-Kelvin Thermal Insulator
Authors: Chawner J. M. A. , Jones A. T. , Noble M. T. , Pickett G. R. , Tsepelin V. , Zmeev D. E. 
Published: December 2019

AbstractWe report measurements of the thermal conductance of a structure made from commercial Acrylonitrile Butadiene Styrene (ABS) modules, known as LEGO® blocks, in the temperature range from 70 mK to 1.8 K. A power law for the sample’s thermal conductivity κ = (8.7 ± 0.3) × 10−5T 1.75±0.02 WK−1 m−1 was determined. We conclude that this ABS/void compound material provides better thermal isolation than well-known bulk insulator materials in the explored temperature range, whilst maintaining solid support. LEGO blocks represent a cheap and superlative alternative to materials such as Macor or Vespel. In our setup, <400 nW of power can heat an experimental area of 5 cm2 to over 1 K, without any significant change to the base temperature of the dilution refrigerator. This work suggests that custom-built modular materials with even better thermal performance could be readily and cheaply produced by 3D printing.
A space division multiplexed free-space-optical communication system that can auto-locate and fully self align with a remote transceiver
Authors: Abadi Mojtaba Mansour , Cox Mitchell A. , Alsaigh Rakan E. , Viola Shaun , Forbes Andrew , Lavery Martin P. J. 
Published: December 2019

AbstractFree-Space Optical (FSO) systems offer the ability to distribute high speed digital links into remote and rural communities where terrain, installation cost or infrastructure security pose critical hurdles to deployment. A challenge in any point-to-point FSO system is initiating and maintaining optical alignment from the sender to the receiver. In this paper we propose and demonstrate a low-complexity self-aligning FSO prototype that can completely self-align with no requirement for initial manual positioning and could therefore form the opto-mechanical basis for a mesh network of optical transceivers. The prototype utilises off-the-shelf consumer electrical components and a bespoke alignment algorithm. We demonstrate an eight fibre spatially multiplexed link with a loss of 15 dB over 210 m.
Sensory-cognitive associations are only weakly mediated or moderated by social factors in the Canadian Longitudinal Study on Aging
Authors: Hämäläinen Anni , Phillips Natalie , Wittich Walter , Pichora-Fuller M. Kathleen , Mick Paul 
Published: December 2019

AbstractSensory and cognitive function both tend to decline with increasing age. Sensory impairments are risk factors for age-related cognitive decline and dementia. One hypothesis about sensory-cognitive associations is that sensory loss results in social isolation which, in turn, is a risk factor for cognitive decline. We tested whether social factors are associated with cognitive and sensory function, and whether sensory-cognitive associations are mediated or moderated by social factors. We used cross-sectional data from 30,029 participants in the Canadian Longitudinal Study of Aging, aged 45–85 years, who had no reported cognitive impairment or diagnosis of dementia. We found strong independent associations of self-reported social variables with hearing (pure-tone audiometry), vision (pinhole-corrected visual acuity), and executive function and weaker associations with memory. The moderating and mediating effects of social variables on sensory-cognitive associations were weak and mostly non-significant, but social factors could be slightly more important for females and older people. Partial retirement (relative to full retirement or not being retired) may have protective effects on cognition in the presence of hearing loss. These findings confirm the association between social factors and sensory and cognitive measures. However, support is weak for the hypothesis that social factors shape sensory-cognitive associations.
Semi-quantized Spin Pumping and Spin-Orbit Torques in Topological Dirac Semimetals
Authors: Misawa Takahiro , Nomura Kentaro 
Published: December 2019

AbstractWe study the time-development processes of spin and charge transport phenomena in a topological Dirac semimetal attached to a ferromagnetic insulator with a precessing magnetization. Compared to conventional normal metals, topological Dirac semimetals manifest a large inverse spin Hall effect when a spin current is pumped from the attached ferromagnetic insulator. It is shown that the induced charge current is semi-quantized, i.e., it depends only on the distance between the two Dirac points in momentum space and hardly depends on the disorder strength when the system remains in the topological Dirac semimetal phase. As an inverse effect, we show that the electric field applied to the topological Dirac semimetal exerts a spin torque on the local magnetization in the ferromagnetic insulator via the exchange interaction and the semi-quantized spin Hall effect. Our study demonstrates that the topological Dirac semimetal offers a less-dissipative platform for spin-charge conversion and spin switching.
The in vivo mechanics of the magnetotactic backbone as revealed by correlative FLIM-FRET and STED microscopy
Authors: Günther Erika , Klauß André , Toro-Nahuelpan Mauricio , Schüler Dirk , Hille Carsten , Faivre Damien 
Published: December 2019

AbstractProtein interaction and protein imaging strongly benefit from the advancements in time-resolved and superresolution fluorescence microscopic techniques. However, the techniques were typically applied separately and ex vivo because of technical challenges and the absence of suitable fluorescent protein pairs. Here, we show correlative in vivo fluorescence lifetime imaging microscopy Förster resonance energy transfer (FLIM-FRET) and stimulated emission depletion (STED) microscopy to unravel protein mechanics and structure in living cells. We use magnetotactic bacteria as a model system where two proteins, MamJ and MamK, are used to assemble magnetic particles called magnetosomes. The filament polymerizes out of MamK and the magnetosomes are connected via the linker MamJ. Our system reveals that bacterial filamentous structures are more fragile than the connection of biomineralized particles to this filament. More importantly, we anticipate the technique to find wide applicability for the study and quantification of biological processes in living cells and at high resolution.
Caveolin-1 gene therapy inhibits inflammasome activation to protect from bleomycin-induced pulmonary fibrosis
Authors: Lin Xin , Barravecchia Michael , Matthew Kottmann R. , Sime Patricia , Dean David A 
Published: December 2019

AbstractIdiopathic pulmonary fibrosis (IPF) is a devastating and fatal disease and characterized by increased deposition of extracellular matrix proteins and scar formation in the lung, resulting from alveolar epithelial damage and accumulation of inflammatory cells. Evidence suggests that Caveolin-1 (Cav-1), a major component of caveolae which regulates cell signaling and endocytosis, is a potential target to treat fibrotic diseases, although the mechanisms and responsible cell types are unclear. We show that Cav-1 expression was downregulated both in alveolar epithelial type I cells in bleomycin-injured mouse lungs and in lung sections from IPF patients. Increased expression of IL-1β and caspase-1 has been observed in IPF patients, indicating inflammasome activation associated with IPF. Gene transfer of a plasmid expressing Cav-1 using transthoracic electroporation reduced infiltration of neutrophils and monocytes/macrophages and protected from subsequent bleomycin-induced pulmonary fibrosis. Overexpression of Cav-1 suppressed bleomycin- or silica-induced activation of caspase-1 and maturation of pro-IL-1β to secrete cleaved IL-1β both in mouse lungs and in primary type I cells. These results demonstrate that gene transfer of Cav-1 downregulates inflammasome activity and protects from subsequent bleomycin-mediated pulmonary fibrosis. This indicates a pivotal regulation of Cav-1 in inflammasome activity and suggests a novel therapeutic strategy for patients with IPF.
Genetic Analysis of High Protein Content in ‘AC Proteus’ Related Soybean Populations Using SSR, SNP, DArT and DArTseq Markers
Authors: Samanfar Bahram , Cober Elroy R. , Charette Martin , Tan Le Hoa , Bekele Wubishet A. , Morrison Malcolm J. , Kilian Andrzej , Belzile François , Molnar Stephen J. 
Published: December 2019

AbstractKey message: Several AC Proteus derived genomic regions (QTLs, SNPs) have been identified which may prove useful for further development of high yielding high protein cultivars and allele-specific marker developments. High seed protein content is a trait which is typically difficult to introgress into soybean without an accompanying reduction in seed yield. In a previous study, ‘AC Proteus’ was used as a high protein source and was found to produce populations that did not exhibit the typical association between high protein and low yield. Five high x low protein RIL populations and a high x high protein RIL population were evaluated by either quantitative trait locus (QTL) analysis or bulk segregant analyses (BSA) following phenotyping in the field. QTL analysis in one population using SSR, DArT and DArTseq markers found two QTLs for seed protein content on chromosomes 15 and 20. The BSA analyses suggested multiple genomic regions are involved with high protein content across the five populations, including the two previously mentioned QTLs. In an alternative approach to identify high protein genes, pedigree analysis identified SNPs for which the allele associated with high protein was retained in seven high protein descendants of AC Proteus on chromosomes 2, 17 and 18. Aside from the two identified QTLs (five genomic regions in total considering the two with highly elevated test statistic, but below the statistical threshold and the one with epistatic interactions) which were some distance from Meta-QTL regions and which were also supported by our BSA analysis within five populations. These high protein regions may prove useful for further development of high yielding high protein cultivars.
Semi-automated Root Image Analysis (saRIA)
Authors: Narisetti Narendra , Henke Michael , Seiler Christiane , Shi Rongli , Junker Astrid , Altmann Thomas , Gladilin Evgeny 
Published: December 2019

AbstractQuantitative characterization of root system architecture and its development is important for the assessment of a complete plant phenotype. To enable high-throughput phenotyping of plant roots efficient solutions for automated image analysis are required. Since plants naturally grow in an opaque soil environment, automated analysis of optically heterogeneous and noisy soil-root images represents a challenging task. Here, we present a user-friendly GUI-based tool for semi-automated analysis of soil-root images which allows to perform an efficient image segmentation using a combination of adaptive thresholding and morphological filtering and to derive various quantitative descriptors of the root system architecture including total length, local width, projection area, volume, spatial distribution and orientation. The results of our semi-automated root image segmentation are in good conformity with the reference ground-truth data (mean dice coefficient = 0.82) compared to IJ_Rhizo and GiAroots. Root biomass values calculated with our tool within a few seconds show a high correlation (Pearson coefficient = 0.8) with the results obtained using conventional, pure manual segmentation approaches. Equipped with a number of adjustable parameters and optional correction tools our software is capable of significantly accelerating quantitative analysis and phenotyping of soil-, agar- and washed root images.
Persistence of arctic-alpine flora during 24,000 years of environmental change in the Polar Urals
Authors: Clarke C. L. , Edwards M. E. , Gielly L. , Ehrich D. , Hughes P. D. M. , Morozova L. M. , Haflidason H. , Mangerud J. , Svendsen J. I. , Alsos I. G. 
Published: December 2019

AbstractPlants adapted to extreme conditions can be at high risk from climate change; arctic-alpine plants, in particular, could “run out of space” as they are out-competed by expansion of woody vegetation. Mountain regions could potentially provide safe sites for arctic-alpine plants in a warmer climate, but empirical evidence is fragmentary. Here we present a 24,000-year record of species persistence based on sedimentary ancient DNA (sedaDNA) from Lake Bolshoye Shchuchye (Polar Urals). We provide robust evidence of long-term persistence of arctic-alpine plants through large-magnitude climate changes but document a decline in their diversity during a past expansion of woody vegetation. Nevertheless, most of the plants that were present during the last glacial interval, including all of the arctic-alpines, are still found in the region today. This underlines the conservation significance of mountain landscapes via their provision of a range of habitats that confer resilience to climate change, particularly for arctic-alpine taxa.
Semantic segmentation of synchrotron tomography of multiphase Al-Si alloys using a convolutional neural network with a pixel-wise weighted loss function
Authors: Strohmann Tobias , Bugelnig Katrin , Breitbarth Eric , Wilde Fabian , Steffens Thomas , Germann Holger , Requena Guillermo 
Published: December 2019

AbstractHuman-based segmentation of tomographic images can be a tedious time-consuming task. Deep learning algorithms and, particularly, convolutional neural networks have become state of the art techniques for pattern recognition in digital images that can replace human-based image segmentation. However, their use in materials science is beginning to be explored and their application needs to be adapted to the specific needs of this field. In the present work, a convolutional neural network is trained to segment the microstructural components of an Al-Si cast alloy imaged using synchrotron X-ray tomography. A pixel-wise weighted error function is implemented to account for microstructural features which are hard to identify in the tomographs and that play a relevant role for the correct description of the 3D architecture of the alloy investigated. The results show that the total operation time for the segmentation using the trained convolutional neural network was reduced to <1% of the time needed with human-based segmentation.