bluuebunny/crossref_metadata_2025_split huggingface dataset:
Multipoint MMS observations of fine‐scale SAPS structure in the inner magnetosphere
Authors: Erickson P. J. , Matsui H. , Foster J. C. , Torbert R. B. , Ergun R. E. , Khotyaintsev Yu. V. , Lindqvist P.‐A. , Argall M. R. , Farrugia C. J. , Paulson K. W. , Strangeway R. J. , Magnes W. 
Published: June 2016

AbstractWe present detailed observations of dynamic, fine‐scale inner magnetosphere‐ionosphere coupling at ∼3.9 RE in the Region 2 Birkeland field‐aligned current (FAC). We find that observed electrodynamic spatial/temporal scales are primarily characteristic of magnetically mapped ionospheric structure. On 15 September 2015, conjugate Magnetospheric Multiscale (MMS) spacecraft and Millstone Hill radar observations show plasmasphere boundary region subauroral polarization stream (SAPS) electric fields at L = 4.0–4.2 near 21 MLT. MMS observations reveal high‐altitude ∼1 mV/m fine‐scale radial and azimuthal electric field perturbations over ≤0.15 L with high spatial coherence over ≥2–3 min and show outward motion within a broader FAC of ∼0.12 μA/m2. Our analysis shows that MMS electric field fluctuations are most likely reflective of SAPS ionospheric structure at scales of ∼22 km and with ionospheric closure of small‐scale filamentary FAC perturbations. The results highlight the ionosphere's importance in regulating fine‐scale magnetosphere‐ionosphere structure.
Controls on circulation, cross‐shelf exchange, and dense water formation in an Antarctic polynya
Authors: Snow K. , Sloyan B. M. , Rintoul S. R. , Hogg A. McC. , Downes S. M. 
Published: June 2016

AbstractCirculation on the Antarctic continental shelf influences cross‐shelf exchange, Antarctic Bottom Water formation, and ocean heat flux to floating ice shelves. The physical processes driving the shelf circulation and its seasonal and interannual variability remain poorly understood. We use a unique time series of repeat hydrographic observations from the Adélie Land continental shelf and a box inverse model to explore the relationship between surface forcing, shelf circulation, cross‐shelf exchange, and dense water formation. A wind‐driven northwestward coastal current, set up by onshore Ekman transport, dominates the summer circulation. During winter, strong buoyancy loss creates dense shelf water. This dense water flows off the shelf, with a compensating on‐shelf flow that is an order of magnitude larger in winter than in summer. The results demonstrate the importance of winter buoyancy loss in driving the shelf circulation and cross‐shelf exchange, as well as dense water mass formation.
Cross‐field current instability for auroral bead formation in breakup arcs
Authors: Lui A. T. Y. 
Published: June 2016

AbstractThe physical process responsible for the onset of substorm expansion is still unresolved in spite of decades of research on the topic. Detailed properties of the spatially periodic auroral beads on prebreakup auroral arcs that initiate substorm expansion onset are now available. These auroral bead properties impose severe observational constraints on the onset process. In this work, theoretical predictions of the cross‐field current instability are evaluated in terms of these constraints. The growth rates and wavelengths associated with auroral beads in several previously published events are reproduced by the cross‐field current instability, implying that the instability can indeed account for the characteristics of auroral beads that eventually lead to substorm onset. The present results differ from the conclusion reached by a previous analysis that the shear flow ballooning instability can account for the growth and spatial scales of auroral beads better than the cross‐field current instability.
Observations of the impenetrable barrier, the plasmapause, and the VLF bubble during the 17 March 2015 storm
Authors: Foster J. C. , Erickson P. J. , Baker D. N. , Jaynes A. N. , Mishin E. V. , Fennel J. F. , Li X. , Henderson M. G. , Kanekal S. G. 
Published: June 2016

AbstractVan Allen Probes observations during the 17 March 2015 major geomagnetic storm strongly suggest that VLF transmitter‐induced waves play an important role in sculpting the earthward extent of outer zone MeV electrons. A magnetically confined bubble of very low frequency (VLF) wave emissions of terrestrial, human‐produced origin surrounds the Earth. The outer limit of the VLF bubble closely matches the position of an apparent barrier to the inward extent of multi‐MeV radiation belt electrons near 2.8 Earth radii. When the VLF transmitter signals extend beyond the eroded plasmapause, electron loss processes set up near the outer extent of the VLF bubble create an earthward limit to the region of local acceleration near L = 2.8 as MeV electrons are scattered into the atmospheric loss cone.
Estuarine circulation versus tidal pumping: Sediment transport in a well‐mixed tidal inlet
Authors: Becherer Johannes , Flöser Götz , Umlauf Lars , Burchard Hans 
Published: June 2016

AbstractHigh‐resolution water column observations have been carried out in the Wadden Sea to understand suspended particulate matter (SPM) transport in well‐mixed tidal channels. These observations include more than 4000 consecutive CTD, microstructure shear and turbidity profiles from a free‐falling microstructure probe, as well as velocity data from an ADCP and SPM samples for calibration. A horizontal density gradient was established by a landward temperature gradient built up during an extraordinarily warm and calm spring season. Tidal averaging along σ‐layers (relative depth) provides the first direct observations of along‐channel estuarine circulation in the Wadden Sea, with net inflow near the bottom and outflow near the surface. Increased westerly (up‐estuary) winds during the second part of the campaign weakened and eventually even reversed estuarine circulation and yielded a net barotropic eastward transport. SPM concentrations showed a strong quarter‐diurnal signal with maxima near full flood and full ebb and were generally lower during the calm period and increased during the windy period, mainly due to wave‐related resuspension over nearby intertidal flats. The sediment flux analysis was based on a decomposition of the vertically integrated SPM flux into a barotropic advective component, an estuarine circulation component and a tidal pumping component. As a result, tidal pumping (due to ebb‐dominance weakly seaward) dominated the SPM flux during calm conditions, whereas barotropic advection dominated the strong landward SPM flux during the windy period. Along‐channel estuarine circulation is found to be of minor importance for the net SPM transport in such well‐mixed systems.
Sunlight induced chlorophyll fluorescence in the near‐infrared spectral region in natural waters: Interpretation of the narrow reflectance peak around 761 nm
Authors: Lu Yingcheng , Li Linhai , Hu Chuanmin , Li Lin , Zhang Minwei , Sun Shaojie , Lv Chunguang 
Published: June 2016

AbstractSunlight induced chlorophyll a fluorescence (SICF) can be used as a probe to estimate chlorophyll a concentrations (Chl) and infer phytoplankton physiology. SICF at ∼685 nm has been widely applied to studies of natural waters. SICF around 740 nm has been demonstrated to cause a narrow reflectance peak at ∼761 nm in the reflectance spectra of terrestrial vegetation. This narrow peak has also been observed in the reflectance spectra of natural waters, but its mechanism and applications have not yet been investigated and it has often been treated as measurement artifacts. In this study, we aimed to interpret this reflectance peak at ∼761 nm and discuss its potential applications for remote monitoring of natural waters. A derivative analysis of the spectral reflectance suggests that the 761 nm peak is due to SICF. It was also found that the fluorescence line height (FLH) at 761 nm significantly and linearly correlates with Chl. FLH(761 nm) showed a tighter relationship with Chl than the relationship between FLH(∼685 nm) and Chl mainly due to weaker perturbations by nonalgal materials around 761 nm. While it is not conclusive, a combination of FLH(761 nm) and FLH(∼685 nm) might have some potentials to discriminate cyanobacteria from other phytoplankton due to their different fluorescence responses at the two wavelengths. It was further found that reflectance spectra with a 5 nm spectral resolution are adequate to capture the spectral SICF feature at ∼761 nm. These preliminary results suggest that FLH(761 nm) need to be explored more for future applications in optically complex coastal and inland waters.
The spectral albedo of sea ice and salt crusts on the tropical ocean of Snowball Earth: 1. Laboratory measurements
Authors: Light Bonnie , Carns Regina C. , Warren Stephen G. 
Published: June 2016

AbstractThe ice‐albedo feedback mechanism likely contributed to global glaciation during the Snowball Earth events of the Neoproterozoic era (1 Ga to 544 Ma). This feedback results from the albedo contrast between sea ice and open ocean. Little is known about the optical properties of some of the possible surface types that may have been present, including sea ice that is both snow‐free and cold enough for salts to precipitate within brine inclusions. A proxy surface for such ice was grown in a freezer laboratory using the single salt NaCl and kept below the eutectic temperature (−21.2°C) of the NaCl‐H2O binary system. The resulting ice cover was composed of ice and precipitated hydrohalite crystals (NaCl · 2H2O). As the cold ice sublimated, a thin lag‐deposit of salt formed on the surface. To hasten its growth in the laboratory, the deposit was augmented by addition of a salt‐enriched surface crust. Measurements of the spectral albedo of this surface were carried out over 90 days as the hydrohalite crust thickened due to sublimation of ice, and subsequently over several hours as the crust warmed and dissolved, finally resulting in a surface with puddled liquid brine. The all‐wave solar albedo of the subeutectic crust is 0.93 (in contrast to 0.83 for fresh snow and 0.67 for melting bare sea ice). Incorporation of these processes into a climate model of Snowball Earth will result in a positive salt‐albedo feedback operating between −21°C and −36°C.
Estimating the recharge properties of the deep ocean using noble gases and helium isotopes
Authors: Loose Brice , Jenkins William J. , Moriarty Roisin , Brown Peter , Jullion Loic , Naveira Garabato Alberto C. , Torres Valdes Sinhue , Hoppema Mario , Ballentine Chris , Meredith Michael P. 
Published: June 2016

AbstractThe distribution of noble gases and helium isotopes in the dense shelf waters of Antarctica reflects the boundary conditions near the ocean surface: air‐sea exchange, sea ice formation, and subsurface ice melt. We use a nonlinear least squares solution to determine the value of the recharge temperature and salinity, as well as the excess air injection and glacial meltwater content throughout the water column and in the precursor to Antarctic Bottom Water. The noble gas‐derived recharge temperature and salinity in the Weddell Gyre are −1.95°C and 34.95 psu near 5500 m; these cold, salty recharge values are a result of surface cooling as well as brine rejection during sea ice formation in Antarctic polynyas. In comparison, the global value for deep water recharge temperature is −0.44°C at 5500 m, which is 1.5°C warmer than the southern hemisphere deep water recharge temperature, reflecting a distinct contribution from the north Atlantic. The contrast between northern and southern hemisphere recharge properties highlights the impact of sea ice formation on setting the gas properties in southern sourced deep water. Below 1000 m, glacial meltwater averages 3.5‰ by volume and represents greater than 50% of the excess neon and argon found in the water column. These results indicate glacial melt has a nonnegligible impact on the atmospheric gas content of Antarctic Bottom Water.
Carbon export fluxes and export efficiency in the central Arctic during the record sea‐ice minimum in 2012: a joint 234Th/238U and 210Po/210Pb study
Authors: Roca‐Martí Montserrat , Puigcorbé Viena , Rutgers van der Loeff Michiel M. , Katlein Christian , Fernández‐Méndez Mar , Peeken Ilka , Masqué Pere 
Published: June 2016

AbstractThe Arctic sea‐ice extent reached a record minimum in September 2012. Sea‐ice decline increases the absorption of solar energy in the Arctic Ocean, affecting primary production and the plankton community. How this will modulate the sinking of particulate organic carbon (POC) from the ocean surface remains a key question. We use the 234Th/238U and 210Po/210Pb radionuclide pairs to estimate the magnitude of the POC export fluxes in the upper ocean of the central Arctic in summer 2012, covering time scales from weeks to months. The 234Th/238U proxy reveals that POC fluxes at the base of the euphotic zone were very low (2 ± 2 mmol C m−2 d−1) in late summer. Relationships obtained between the 234Th export fluxes and the phytoplankton community suggest that prasinophytes contributed significantly to the downward fluxes, likely via incorporation into sea‐ice algal aggregates and zooplankton‐derived material. The magnitude of the depletion of 210Po in the upper water column over the entire study area indicates that particle export fluxes were higher before July/August than later in the season. 210Po fluxes and 210Po‐derived POC fluxes correlated positively with sea‐ice concentration, showing that particle sinking was greater under heavy sea‐ice conditions than under partially ice‐covered regions. Although the POC fluxes were low, a large fraction of primary production (>30%) was exported at the base of the euphotic zone in most of the study area during summer 2012, indicating a high export efficiency of the biological pump in the central Arctic.
Correlation of T2R38 taste phenotype and in vitro biofilm formation from nonpolypoid chronic rhinosinusitis patients
Authors: Adappa Nithin D. , Truesdale Carl M. , Workman Alan D. , Doghramji Laurel , Mansfield Corrine , Kennedy David W. , Palmer James N. , Cowart Beverly J. , Cohen Noam A. 
Published: June 2016

BackgroundSinonasal biofilms have been demonstrated in specimens collected from chronic rhinosinusitis (CRS) patients. Mounting evidence suggests that biofilms contribute to therapeutically recalcitrant CRS. Recently, the bitter taste receptor T2R38 has been implicated in the regulation of the sinonasal mucosal innate immune response. TAS2R38 gene polymorphisms affect receptor functionality and contribute to variations seen in sinonasal innate defense as well as taste perception reflected in gustatory sensitivity to the bitter compound phenylthiocarbamide (PTC). In a population of CRS patients with active infection or inflammation, we sought to determine if a correlation between T2R38 phenotype and in vitro biofilm formation existed.MethodsEndoscopically guided sinonasal swabs were obtained prospectively from CRS (±polyp) patients with evidence of persistent inflammation or mucopurulence. In vitro biofilm formation was assessed with a modified Calgary Biofilm Detection Assay. Patients’ phenotypic (functional) expression of the bitter taste receptor T2R38 was evaluated with a taste test including the compound PTC. Linear regression was used to determine the level of significance between mean in vitro biofilm formation levels and mean PTC taste test intensity ratings across CRS patients.ResultsSinonasal swabs were obtained from 59 patients, with 42 of the 59 samples demonstrating in vitro biofilm formation. Analysis revealed an inverse linear association between in vitro biofilm formation and PTC taste intensity ratings (p = 0.019) for all patients. This association was exclusively driven by nonpolypoid CRS patients (p = 0.0026).ConclusionIn vitro biofilm formation from sinonasal clinical isolates is inversely correlated with PTC taste sensitivity in nonpolypoid CRS patients.
Health utility values for patients with recurrent acute rhinosinusitis undergoing endoscopic sinus surgery: a nested case control study
Authors: Steele Toby O. , Mace Jess C. , Dedhia Raj , Rudmik Luke , Smith Timothy L. , Alt Jeremiah A. 
Published: June 2016

BackgroundHealth utility scores quantify an individual's valuation of particular health states and are vital components of health economic studies and cost‐effectiveness research. We sought to characterize health utility values for patients with recurrent acute rhinosinusitis (RARS) both before and after endoscopic sinus surgery (ESS), as well as compare health utility to chronic rhinosinusitis without nasal polyposis (CRSsNP).MethodsPatients with RARS (n = 20) and CRSsNP (n = 20) undergoing ESS were enrolled as part of a longitudinal, observational, prospective cohort. Case patients diagnosed with RARS were age‐ and gender‐matched to controls with CRSsNP using a nested case‐control design at a 1:1 ratio. Health utility was measured using the Medical Outcomes Study Short Form‐6D (SF‐6D) survey.ResultsPatients with RARS were followed for an average of 14.0 ± 6.1 (mean ± standard deviation) months compared to an average of 14.4 ± 5.3 months for CRSsNP controls (p = 0.779). Mean preoperative SF‐6D health utility scores were statistically comparable between RARS (0.71 ± 0.14) and CRSsNP (0.66 ± 0.12; p = 0.341). Both patients with RARS and CRSsNP reported significant postoperative improvement in SF‐6D scores from 0.71 ± 0.14 to 0.79 ± 0.13 (p = 0.031) and from 0.66 ± 0.12 to 0.77 ± 0.13 (p = 0.004), respectively. No difference in last postoperative SF‐6D scores were found between RARS and CRSsNP (p = 0.583) or in the average magnitude of postoperative improvement (0.08 ± 0.16 vs 0.11 ± 0.13; p = 0.620).ConclusionPatients with RARS and CRSsNP report significant impairment in health utility as measured by the SF‐6D. ESS significantly improves health utility in patients with RARS and CRSsNP to near normative values. These data will help inform future economic analysis and cost‐effectiveness research.
Huge Differences in the Kinetics of Swelling Enhancement and De‐enhancement of Permanently Charged Polyelectrolyte Brushes
Authors: Chu Xiao , Yang Jingfa , Zhao Jiang 
Published: June 2016

AbstractAs demonstrated previously (X. Chu et al., Soft Matter 2014, 10, 5568), permanently charged polyelectrolyte brushes can experience an enhancement of swelling by exposure to an external monovalent salt solution in moderate concentrations. Beyond the previous static measurements, the kinetics of the swelling enhancement and de‐enhancement were investigated in the current study by using a quartz crystal microbalance with dissipation (QCM‐D). By developing an effective approach to quantify the response in QCM‐D, a vast difference in swelling enhancement and de‐enhancement of a model permanently charged polyelectrolyte brush (sodium polystyrene sulfonate, NaPSS) was discovered. The results indicate new physics of the charged brushes: the difference in the attachment and detachment of counterions to the polyelectrolyte chains.
Benzodipyrrole‐based Donor–Acceptor‐type Boron Complexes as Tunable Near‐infrared‐Absorbing Materials
Authors: Nakamura Tomoya , Furukawa Shunsuke , Nakamura Eiichi 
Published: June 2016

AbstractBenzodipyrrole‐based donor–acceptor boron complexes were designed and synthesized as near‐infrared‐absorbing materials. The electron‐rich organic framework combined with the Lewis acidic boron co‐ordination enabled us to tune the LUMO energy level and the HOMO–LUMO gap (i.e.,the absorption wavelength) by changing the organic acceptor units, the number of boron atoms, and the substituents on the boron atoms.
Trends in extreme precipitation indices across China detected using quantile regression
Authors: Fan Lijun , Chen Deliang 
Published: June 2016

AbstractFor China, long‐term changes are detected not only in the means of eight extreme precipitation indices, but also in their distribution shapes by quantile regression. This resulted in different trends for the means and other aspects of the index distributions. The differences between changes in the means and upper/lower extremes vary with region and index. A noteworthy feature is that changes in upper tails of the index distributions across a broad area, especially in the south, are at a much higher rate than mean trends estimated by the traditional linear regression model. This has practical implications for disaster risk management.
Hurricane simulation using different representations of atmosphere–ocean interaction: the case of Irene (2011)
Authors: Mooney P. A. , Gill D. O. , Mulligan F. J. , Bruyère C. L. 
Published: June 2016

AbstractThree approaches to represent sea surface temperatures (SSTs) in atmospheric models have been investigated using the Weather Research and Forecasting model: (1) prescribing SSTs every 6 h from reanalysis, (2) a one‐dimensional ocean mixed‐layer model and (3) a fully coupled regional ocean model. Hurricane Irene (2011) was chosen as the test case. All three options produced results comparable to observations immediately after storm passage but only options (1) and (3) captured recovery to pre‐storm conditions which suggests both are feasible approaches for long‐term simulations of tropical cyclones. Option (2) merits further investigation because of its greater computational efficiency and reduced complexity.
Interactions between Bacillus cereus CGMCC 1.895 and Clostridium beijerinckii NCIMB 8052 in coculture for butanol production under nonanaerobic conditions
Authors: Mai Shuai , Wang Genyu , Wu Pengfei , Gu Chunkai , Liu Hongjuan , Zhang Jianan , Wang Gehua 
Published: June 2016

AbstractLow oxygen tolerance and substrate restriction continues to hamper the process of biobutanol industrialization. In this work, butanol fermentation with cocultures of Bacillus cereus China General Microbiological Culture Collection Center (CGMCC) 1.895 and Clostridium beijerinckii NCIMB 8052 under nonanaerobic conditions was investigated, and the interactions between these two strains were examined. The addition of B. cereus CGMCC 1.895 resulted in higher oxygen tolerance and a wider range of substrate utilization, compared with the pure culture of C. beijerinckii NCIMB 8052. Butanol concentration reached 10.49 g/L with an optimized inoculation size of 90% under nonanaerobic conditions, and this concentration was close to that of pure C. beijerinckii NCIMB 8052 culture under anaerobic conditions. Dynamic relative abundance analysis demonstrated that the ratio of C. beijerinckii NCIMB 8052 accounted for nearly 99% of the cocultured cells. Furthermore, the substrate utilization range was expanded, allowing the use of corn mash for butanol production. The final concentration of butanol and total solvents was 6.78 and 10.52 g/L, respectively. Coculture also was performed successfully in a 5‐L fermenter and 8.75 g/L butanol was obtained. Dynamic dissolved oxygen analysis demonstrated that B. cereus consumed the dissolved oxygen in the broth and resulted in the anaerobic condition for C. beijerinckii.
Avoiding collateral damage in the war on hypertension
Authors: Bates Mark C. 
Published: June 2016

Key Points

When performed by experienced clinicians, renal nerve denervation (RND) can be done with very low risk of complication and/or acute renal injury
Renal function seems to remain unchanged in this small series over 3 years
More studies are needed to establish the role of renal biomarkers in assessment of acute renal injury in this setting and larger series of RND in azotemic patients should be done before the procedure indications can be expanded
Percutaneous closure of residual leaks after device occlusion of the left atrial appendage
Authors: Feldman Ted 
Published: June 2016

Key Points

Large leaks (≥ 3mm) after percutaneous left atrial appendage (LAA) device occlusion may occur in about 2% of cases.
There is no clear relationship between incomplete occlusion of the LAA and risk of thromboembolism.
Leak closure with percutaneous devices is feasible and safe.
A small percentage incidence of leaks after device closure in the large LAA device closure population represents a significant number of patients.