bluuebunny/crossref_metadata_2025_split huggingface dataset:
CNOP‐Based Adaptive Observation Network Designed for Improving Upstream Kuroshio Transport Prediction
Authors: Zhang Kun , Mu Mu , Wang Qiang , Yin Baoshu , Liu Shixuan 
Published: June 2019

AbstractUsing the Regional Ocean Modeling System and the conditional nonlinear optimal perturbation (CNOP) approach, this study explored a CNOP‐based adaptive observation system design with regard to improving the prediction of one seasonal upstream Kuroshio transport (UKT) reduction event. For comparison, investigations were also conducted using a set of random observation systems built within a sensitive area inferred from previous studies and a conventional observation system built at 18°N. For these observation systems, observation networks constructed using different numbers of observation sites and observation distances (i.e., the shortest distances between any two observation sites) were evaluated by performing observing system simulation experiments. Results showed that most assimilation experiments can improve the UKT prediction, indicating the importance of initial conditions. For all observation systems, large numbers of observation sites generally led to higher prediction benefits, whereas the effects of observation distances differed significantly. Overall, the CNOP‐based observation system exhibited the best performance. Optimal CNOP‐based observation networks were established using six or eight observation sites and observation distances of 140 or 165 km, which produced a mean prediction improvement of 43.1%. This preliminary work is expected to provide guidance on future observations in the upstream Kuroshio region and to help realistic UKT predictions.
Collapsing Complexity: Quantifying Multiscale Properties of Reef Topography
Authors: Duvall Melissa S. , Hench James L. , Rosman Johanna H. 
Published: June 2019

AbstractSeafloor topography affects a wide range of physical and biological processes; therefore, collapsing the three‐dimensional structure of the bottom to roughness metrics is a common challenge in studies of marine systems. Here we assessed the properties captured by metrics previously proposed for the seafloor, as well as metrics developed to characterize other types of rough surfaces. We considered three classes of metrics: properties of the bottom elevation distribution (e.g., standard deviation), length scale ratios (e.g., rugosity), and metrics that describe how topography varies with spatial scale (e.g., Hölder exponents). The metrics were assessed using idealized topography and natural seafloor topography data from airborne lidar measurements of a coral reef. We illustrate that common roughness metrics (e.g., rugosity) can have the same value for topographies that are geometrically very different, limiting their utility. Application of the wavelet leaders technique to the reef data set demonstrates that the topography has a power law scaling behavior, but it is multifractal so a distribution of Hölder exponents is needed to describe its scaling behavior. Using principal component analysis, we identify three dominant modes of topographic variability, or ways metrics covary, among and within reef zones. Collectively, the results presented here show that coral reef topography is both multiscale and multifractal. While individual metrics that capture specific topography properties relevant to a given process may be suitable for some studies, many applications will require a set of metrics that includes statistics that capture how topography varies with spatial scale.
Weakening of the Teleconnection From El Niño–Southern Oscillation to the Arctic Stratosphere Over the Past Few Decades: What Can Be Learned From Subseasonal Forecast Models?
Authors: Garfinkel Chaim I. , Schwartz Chen , Butler Amy H. , Domeisen Daniela I. V. , Son Seok‐Woo , White Ian P. 
Published: June 2019

AbstractWhile a connection between the El Niño–Southern Oscillation (ENSO) and the Northern Hemisphere wintertime stratospheric polar vortex appears robust in observational studies focusing on the period before 1979 and in many modeling studies, this connection is not evident over the past few decades. In this study, the factors that have led to the disappearance of the ENSO‐vortex relationship are assessed by comparing this relationship in observational data and in operational subseasonal forecasting models over the past few decades. For reforecasts initialized in December, the models simulate a significantly weaker vortex during El Niño than La Niña (LN) as occurred before 1979, but no such effect was observed to have occurred. The apparent cause of this is the eastern European and western Siberian height anomalies present during ENSO. The observed LN events were associated with persistent ridging over eastern Europe as compared to El Niño. Although the Subseasonal‐to‐Seasonal models are initialized with this ridge, the ridge quickly dissipates. As ridging over this region enhances wave flux entering the stratosphere, the net effect is no robust stratospheric response to ENSO in the observations despite a North Pacific teleconnection that would, in isolation, lead to less wave flux for LN. The anomalies in the eastern European sector in response to ENSO likely reflect unforced internal atmospheric variability.
Electron Diffusion Regions in Magnetotail Reconnection Under Varying Guide Fields
Authors: Chen L.‐J. , Wang S. , Hesse M. , Ergun R. E. , Moore T. , Giles B. , Bessho N. , Russell C. , Burch J. , Torbert R. B. , Genestreti K. J. , Paterson W. , Pollock C. , Lavraud B. , Le Contel O. , Strangeway R. , Khotyaintsev Yu V. , Lindqvist P.‐A. 
Published: June 2019

AbstractKinetic structures of electron diffusion regions (EDRs) under finite guide fields in magnetotail reconnection are reported. The EDRs with guide fields 0.14–0.5 (in unit of the reconnecting component) are detected by the Magnetospheric Multiscale spacecraft. The key new features include the following: (1) cold inflowing electrons accelerated along the guide field and demagnetized at the magnetic field minimum while remaining a coherent population with a low perpendicular temperature, (2) wave fluctuations generating strong perpendicular electron flows followed by alternating parallel flows inside the reconnecting current sheet under an intermediate guide field, and (3) gyrophase bunched electrons with high parallel speeds leaving the X‐line region. The normalized reconnection rates for the three EDRs range from 0.05 to 0.3. The measurements reveal that finite guide fields introduce new mechanisms to break the electron frozen‐in condition.
In Search of Winter Blocking in the Western North Pacific Ocean
Authors: Kim Seon‐Hwa , Kim Baek‐Min 
Published: June 2019

AbstractWe investigate winter blocking activity over the western North Pacific (WNP) through an intercomparison of four detection methods, which are categorized into two types (anomaly and reversal). Most of the blocking events in the anomaly‐based methods are initiated from the eastern North Pacific. Reversal‐based methods capture the blocking occurrence associated with Rossby wave breaking, especially cyclonic breaking. As the two types capture different aspects of WNP blocking, the resultant regional impact is also largely different. At the onset, anomaly‐based methods show a strong cold anomaly downstream of the blocking in conjunction with a Pacific/North America‐like pattern. Reversal‐based methods indicate a weak cold anomaly in company with a western Pacific‐like pattern, which appears downstream and upstream of the blocking in the local reversal and large‐scale reversal methods, respectively. At the end of WNP blocking, all methods show strong cold anomalies both upstream and downstream of the blocking.
Response to Channel Deepening of the Salinity Intrusion, Estuarine Circulation, and Stratification in an Urbanized Estuary
Authors: Ralston David K. , Geyer W. Rockwell 
Published: June 2019

AbstractModifications for navigation since the late 1800s have increased channel depth (H) in the lower Hudson River estuary by 10–30%, and at the mouth the depth has more than doubled. Observations along the lower estuary show that both salinity and stratification have increased over the past century. Model results comparing predredging bathymetry from the 1860s with modern conditions indicate an increase in the salinity intrusion of about 30%, which is roughly consistent with the H5/3 scaling expected from theory for salt flux dominated by steady exchange. While modifications including a recent deepening project have been concentrated near the mouth, the changes increase salinity and threaten drinking water supplies more than 100 km landward. The deepening has not changed the responses to river discharge (Qr) of the salinity intrusion (~Qr−1/3) or mean stratification (Qr2/3). Surprisingly, the increase in salinity intrusion with channel deepening results in almost no change in the estuarine circulation. This contrasts sharply with local scaling based on local dynamics of an H2 dependence, but it is consistent with a steady state salt balance that allows scaling of the estuarine circulation based on external forcing factors and is independent of depth. In contrast, the observed and modeled increases in stratification are opposite of expectations from the steady state balance, which could be due to reduction in mixing with loss of shallow subtidal regions. Overall, the mean shift in estuarine parameter space due to channel deepening has been modest compared with the monthly‐to‐seasonal variability due to tides and river discharge.
Field Correlations in Surface Plasmon Speckle
Authors: Foreman Matthew R. 
Published: June 2019

AbstractIn this work fluctuations in the electric field of surface plasmon polaritons undergoing random scattering on a rough metallic surface are considered. A rigorous closed form analytic expression is derived describing second order correlations in the resulting plasmon speckle pattern assuming statistically stationary and isotropic roughness. Partially coherent planar Schell-model source fields can also be described within the developed framework. Behaviour of the three-dimensional degree of cross polarisation and spectral degree of coherence is also discussed. Expressions derived take full account of dissipation in the metal with non-universal behaviour exhibited within the correlation length of the surface and source fields.
Changing substrate specificity and iteration of amino acid chain elongation in glucosinolate biosynthesis through targeted mutagenesis ofArabidopsismethylthioalkylmalate synthase 1
Authors: Petersen Annette , Hansen Lea Gram , Mirza Nadia , Crocoll Christoph , Mirza Osman , Halkier Barbara Ann 
Published: June 2019

AbstractMethylthioalkylmalate synthases catalyse the committing step of amino acid chain elongation in glucosinolate biosynthesis. As such, this group of enzymes plays an important role in determining the glucosinolate composition of Brassicaceae species, including Arabidopsis thaliana. Based on protein structure modelling of MAM1 from A. thaliana and analysis of 57 MAM sequences from Brassicaceae species, we identified four polymorphic residues likely to interact with the 2-oxo acid substrate. Through site-directed mutagenesis, the natural variation in these residues and the effect on product composition were investigated. Fifteen MAM1 variants as well as the native MAM1 and MAM3 from A. thaliana were characterised by heterologous expression of the glucosinolate chain elongation pathway in Escherichia coli. Detected products derived from leucine, methionine or phenylalanine were elongated with up to six methylene groups. Product profile and accumulation were changed in 14 of the variants, demonstrating the relevance of the identified residues. The majority of the single amino acid substitutions decreased the length of methionine-derived products, while approximately half of the substitutions increased the phenylalanine-derived products. Combining two substitutions enabled the MAM1 variant to increase the number of elongation rounds of methionine from three to four. Notably, characterisation of the native MAMs indicated that MAM1 and not MAM3 is responsible for homophenylalanine production. This hypothesis was confirmed by glucosinolate analysis in mam1 and mam3 mutants of A. thaliana.
When the tale comes true: multiple populations and wide binaries in the Orion Nebula Cluster
Authors: Jerabkova Tereza , Beccari Giacomo , Boffin Henri M. J. , Petr-Gotzens Monika G. , Manara Carlo F. , Prada Moroni Pier Giorgio , Tognelli Emanuele , Degl’Innocenti Scilla 
Published: June 2019

Context. Recently published high-quality OmegaCAM photometry of the 3 × 3 deg around the Orion Nebula Cluster (ONC) in r, and i filters revealed three well-separated pre-main sequences in the color-magnitude diagram (CMD). The objects belonging to the individual sequences are concentrated toward the center of the ONC. The authors concluded that there are two competitive scenarios: a population of unresolved binaries and triples with an exotic mass ratio distribution, or three stellar populations with different ages (≈1 Myr age differences).
Aims. We use Gaia DR2 in combination with the photometric OmegaCAM catalog to test and confirm the presence of the putative three stellar populations. We also study multiple stellar systems in the ONC for the first time using Gaia DR2.
Methods. We selected ONC members based on parallaxes and proper motions and take advantage from OmegaCAM photometry that performs better than Gaia DR2 photometry in crowded regions. We identify two clearly separated sequences with a third suggested by the data. We used Pisa stellar isochrones to estimate ages of the stellar populations with absolute magnitudes computed using Gaia parallaxes on a star by star basis.
Results. (1) We confirm that the second and third sequence members are more centrally concentrated toward the center of the ONC. In addition we find an indication that the parallax and proper motion distributions are different among the members of the stellar sequences. The age difference among stellar populations is estimated to be 1−2 Myr. (2) We use Gaia proper motions and other measures to identify and remove as many unresolved multiple system candidates as possible. Nevertheless we are still able to recover two well-separated sequences with evidence for the third one, supporting the existence of the three stellar populations. (3) Due to having ONC members with negligible fore- or background contamination we were able to identify a substantial number of wide binary objects (separation between 1000 and 3000 au) and with relative proper motions of the binary components consistent with zero. This challenges previously inferred values that suggested no wide binary stars exist in the ONC. Our inferred wide-binary fraction is ≈5%.
Conclusions. We confirm the three populations correspond to three separated episodes of star formation. Based on this result, we conclude that star formation is not happening in a single burst in this region. In addition we identify 5% of wide-binary stars in the ONC that were thought not to be present.
J-PLUS: Discovery and characterisation of ultracool dwarfs using Virtual Observatory tools
Authors: Solano E. , Martín E. L. , Caballero J. A. , Rodrigo C. , Angulo R. E. , Alcaniz J. , Borges Fernandes M. , Cenarro A. J. , Cristóbal-Hornillos D. , Dupke R. A. , Alfaro E. , Ederoclite A. , Jiménez-Esteban F. , Hernandez-Jimenez J. A. , Hernández-Monteagudo C. , Lopes de Oliveira R. , López-Sanjuan C. , Marín-Franch A. , Mendes de Oliveira C. , Moles M. , Orsi A. , Schmidtobreick L. , Sobral D. , Sodré L. , Varela J. , Vázquez Ramió H. 
Published: June 2019

Context. Ultracool dwarfs are objects with spectral types equal to or later than M7. Most of them have been discovered using wide-field imaging surveys. The Virtual Observatory has proven to be very useful for efficiently exploiting these astronomical resources.
Aims. We aim to validate a Virtual Observatory methodology designed to discover and characterise ultracool dwarfs in the J-PLUS photometric survey. J-PLUS is a multiband survey carried out with the wide-angle T80Cam optical camera mounted on the 0.83 m telescope JAST/T80 in the Observatorio Astrofísico de Javalambre. We make use of the Internal Data Release covering 528 deg2.
Methods. We complemented J-PLUS photometry with other catalogues in the optical and infrared using VOSA, a Virtual Observatory tool that estimates physical parameters from the spectral energy distribution fitting to collections of theoretical models. Objects identified as ultracool dwarfs were distinguished from background M giants and highly reddened stars using parallaxes and proper motions from Gaia DR2.
Results. We identify 559 ultracool dwarfs, ranging from i = 16.2 mag to i = 22.4 mag, of which 187 are candidate ultracool dwarfs not previously reported in the literature. This represents an increase in the number of known ultracool dwarfs of about 50% in the region of the sky we studied, particularly at the faint end of our sensitivity, which is interesting as reference for future wide and deep surveys such as Euclid. Three candidates are interesting targets for exoplanet surveys because of their proximity (distances less than 40 pc). We also analysed the kinematics of ultracool dwarfs in our catalogue and found evidence that it is consistent with a Galactic thin-disc population, except for six objects that might be members of the thick disc.
Conclusion. The results we obtained validate the proposed methodology, which will be used in future J-PLUS and J-PAS releases. Considering the region of the sky covered by the Internal Data Release used in this work, we estimate that 3000–3500 new ultracool dwarfs will be discovered at the end of the J-PLUS project.
POSSIBLE ASSOCIATION OF HLA AND Gm WITH THE ALLOIMMUNE RESPONSE TO FVIII
Authors: Reisner H M , Reisner E A , Kostyu D D , Lubahn B C , McMillan C , White G C 
Published: June 2019

Between 5 and 15% of individuals with severe hemophilia A are at risk of developing inhibitors (alloantibodies) to FVIII. Genetic factors are important in determining risk, but the nature of these factors is poorly defined. The human immune response to a wide variety of antigens has been associated with the HLA and/or Gm loci. Hence, we have investigated polymorphisms at these two loci in hemophilia A patients with and without inhibitors.DATA SET: To date 127 hemophiliacs have been Gm or HLA typed. Forty-eight are inhibitor positive (I+) based on positive FVIII neutralization assays.	This represents about 70% of all I+ hemophiliacs seen at UNC. To prevent familial bias, one member of each of 14 pairs of close relatives was randomly removed from the Data Set without regard to inhibitor status (Data Set 1). Twenty non-white individuals were also removed to constitute Data Set 2. GM TYPING: Samples were typed for Gm antigens 1, 3 and 5. Phenotype frequencies in Data Sets 1 and 2 did not deviate from expected values. I+ hemophiliacs showed an excess of Gm 1 in both Data Sets which was of possible significance (p = .13 and .21 respectively by chi square). Reanalysis of Data Set 2 to include only I- individuals without evidence of either circulating VIII:C or VIII:CAg (N=58) yields a p of .12. HLA TYPING: Analysis on 77 individuals in Data Set 2 (21 I+, 56 I-) has been done. In preliminary typing of HLA A, B, C, DR and DQ no significant differences in antigen frequency were found between the I+ and I- groups. INTERACTION BETWEEN HLA AND GM: A significant excess of Gm 1 I+ individuals was found among all HLA-A2 positive hemophiliacs (N=45, p=.034 by Fisher’s exact test. This was not significant after correction for multiple comparisons). This suggestion of an interaction between HLA-A2 and Gm 1 in determining alloreactivity to FVIII will require further prospective evaluation for confirmation.
LONG TERM, FREQUENT PLASMA EXCHANGE DONATION OF CRYOPRECIPITATE
Authors: McLeod B , Sassetti R , Cole E , Scott P 
Published: June 2019

In plasma exchange donation (PED), several liters of fresh plasma are removed fran a donor with a pheresis instrument as a source of cryoprecipitate, and replaced with autologous cryoprecipitate-supernatant from the previous donation. Repetitive PED can produce large quantities of factor VIII from individual donors over time, with a favorable impact on donor exposure for factor VIII recipients. To clarify the implications for donor safety, we report our experience with several donors who have undergone multiple PEDs. Detailed observations are presented for one donor who has undergone PED 101 times between 5/83 and 1/87, and has provided all the factor VIII needed by his son (now age 14) with severe hemophilia A during this period. Exchange volume was gradually increased while donation frequency was gradually decreased. There were 23 exchanges of 2 L, 52 of 2.5 L, and 26 of 3 L for a total of 254 L plasma exchanged. Desmopressin (20 meg tV) was given before 45 more recent donations to augment factor VIII yield. A total of 343,274 IU factor VIII have been collected; the mean (±SD) yield from a 3 L, desmopressin- stimulated PED is 5598 ± 899 IU. The donor has remained in good health; he has noted no adverse effects fran any PED, and none have been found in laboratory monitoring. Prior to the 100th donation the following were within normal limits: CBC,platelet count, urinalysis, SMA-18, protein electrophoresis, IgG, IgA, IgM,	hemolytic complement, C3, C4, fibronectin, prothrombin time, partial thromboplastin time, thranbin time, factor VIII:C (140%), factor VIII:Ag (134%), von Willebrand factor (86%) and fibrinogen (215 mg/dL). In another family, the father has donated 40 times	since 1981 and the paternal grandmother has donated 31 times since 1984 with no untoward effects detected in clinical or laboratory monitoring. They have supported two moderately affected patients now ages 7 and 9. Extensive experience with these donors suggests that repeated PED is safe, and that a highly motivated donor can sometimes provide single donor support, even for a severe hemophiliac.