bluuebunny/crossref_metadata_2025 huggingface dataset:
Nutrient-uptake and -use efficiency in seedlings of rain-forest trees in New Caledonia: monodominants vs. subordinates and episodic vs. continuous regenerators
Authors: Read Jennifer , McCoy Stéphane , Jaffré Tanguy , Logan Murray
Published: July 2018

The upper canopy of some rain forests in New Caledonia is dominated by single species. These monodominants are commonly secondary species, their dominance not persisting without disturbance. We tested whether dominance is associated with efficient uptake and use of nutrients (N, P and K), comparing between seedlings of monodominants (Nothofagus spp., Arillastrum gummiferum and Cerberiopsis candelabra) and 14 subordinates, grown in a nursery house. We also tested whether this trend applies more broadly to shade-intolerant trees that regenerate episodically (ER species) versus shade-tolerant trees that regenerate continuously (CR species). In the sun treatment, monodominants had higher photosynthetic nutrient-use efficiency and productivity for N and K, and uptake efficiency for N, P and K, than subordinates; ER species had higher photosynthetic nutrient-use efficiency for N, P and K, and uptake efficiency for N and P, than CR species. Uptake efficiency and productivity per nutrient mass were uncorrelated across species, yet Nothofagus spp., A. gummiferum and C. candelabra combined high levels of both traits for N, and Nothofagus spp. and A. gummiferum combined moderate to high levels for P, in sun-grown seedlings. This trait combination may contribute substantially to competitiveness and post-disturbance dominance on these nutrient-poor soils.
Governing Juridical Sex: Gender Recognition and the Biopolitics of Trans Sterilization in Finland
Authors: Repo Jemima
Published: July 2018

In many countries, compulsory sterilization is still a precondition for amending juridical sex. Drawing on feminist and queer debates on the entanglement of recognition with governmentalization, this article moves beyond a human rights frame to examine how struggles for legal gender recognition are bound up with the production and discipline of trans subjectivities, bodies, and relationships. It argues that rights and recognition may not only reinscribe regulation, but also they are a means of rendering trans subjects governable. By theorizing gender identity as a biopolitical discourse that produces trans subjects, the article genealogically examines the problematization of “gender identity” in Finnish welfare population governance practices leading up to the 2003 Finnish gender recognition law. The analysis demonstrates how the discourse of “equality” was key for producing a clearly defined trans population that could be identified, assessed, and, hence, governed. While the sterilization requirement was justified as a replacement for former castration laws which had been used by male-to-female transsexuals to access genital surgery, it also acted as a disciplinary technology to neutralize the alleged threats to normative forms of kinship that could be produced through gender recognition. Finally, the article considers points of resistance and avenues for further research.
Contemporary approaches in mental health rehabilitation
Authors: van der Meer L. , Wunderink C.
Published: July 2018

In many European countries, deinstitutionalisation has been an ongoing process over the last few decades. Mental health organisations were transformed to provide support in a more integrated and comprehensive manner, preferably in their own homes in the community. Yet, despite the welcome aspiration of community integration for all, people with complex mental health problems (also termed severe mental illness) have continued to require high levels of support, in inpatient settings and in the community. This group's needs make them highly dependent on their caregivers. The attitudes, knowledge and skills of the staff providing treatment and support is crucial to their recovery. Rehabilitation programmes provide a much-needed framework to guide practitioners and help them organise and focus their recovery-oriented approach. In this editorial, we will provide a non-exhaustive overview of such rehabilitation programmes and interventions to illuminate the wide scope and practical usability of these interventions for this group of people with complex mental health problems.
Kinetic Alfvén Waves Excited in Two‐Dimensional Magnetic Reconnection
Authors: Huang Hongtao , Yu Yiqun , Dai Lei , Wang Tieyan
Published: July 2018

Kinetic Alfvén waves (KAWs) are believed to be capable of efficiently transporting energy and play an important role in facilitating magnetic reconnection. KAW eigenmode theory suggests that Hall fields can be considered as the components of KAW, providing a mechanism for the generation and dissipation of KAW in magnetic reconnection. Using particle‐in‐cell simulations, we examined Hall fields in the magnetic reconnection region and found that (1) Hall electric filed is balanced by the ion pressure gradient and (2) the ratio of Hall electric field to Hall magnetic field is on the order of Alfvén speed. These results are consistent with KAW physics. Simulation results also indicate that KAWs are excited in the reconnection site and then transmitted along the separatrices. The wave Poynting flux propagates parallel to the magnetic field lines, carrying substantial energy. It is further found that a thinner current sheet provides a favorable condition for the excitation of KAW and results in a higher ratio of the Hall fields.
Dynamic Initialization for Whole Atmospheric Global Modeling
Authors: Song I.‐S. , Chun H.‐Y. , Jee G. , Kim S.‐Y. , Kim J. , Kim Y.‐H. , Taylor M. A.
Published: July 2018

An iterative dynamic initialization method is presented to produce balanced initial conditions for whole atmospheric global modeling. In this method, a global hydrostatic numerical model is iteratively nudged toward ground‐to‐space wind and temperature profiles at specific date and time. Ground‐to‐space atmospheric profiles are obtained by fitting spline curves to reanalyses below the lower mesosphere and empirical model results in the upper atmosphere. An optimal nudging coefficient is determined by examining if reasonable structure of mesospheric gravity wave (GW) momentum forcing and residual mean meridional circulations can be obtained from balanced initial conditions. Estimated mesospheric GW momentum forcing is found to exhibit a distinctive structure with larger (smaller) values in the lower and upper mesosphere (in the midmesosphere), when compared with parameterized climatological forcing. The iterative dynamic initialization allows for dynamical balance among the model's prognostic variables and reduces excitation of spurious GWs and noises at initial time. However, theoretical imbalances, measured by the ellipticity of the nonlinear balance equation, are not completely eliminated in balanced flows, and they are found in narrow tropospheric frontal regions and over localized areas associated with the large‐scale instability in the midlatitude middle atmosphere. These imbalances are discussed in the context of their potential relation to generation of planetary‐scale and inertia GWs around the middle atmospheric and tropospheric jets.
How Are Sediment Pulses Generated?
Authors: Cook Terri
Published: July 2018

A new long-term flume experiment shows that bed load gravel travels downstream in recurring, 10-hour pulses even when water flow and sediment supply are constant.
An SLS5 Longitude System Based on the Rotational Modulation of Saturn Radio Emissions
Authors: Ye S.‐Y. , Fischer G. , Kurth W. S. , Menietti J. D. , Gurnett D. A.
Published: July 2018

Despite the axisymmetry of Saturn's internal field, Saturn radio emissions like Saturn kilometric radiation (SKR) are modulated due to planetary rotation. With the completion of Cassini mission in September 2017, we now have around 14 years of observation of Saturn radio emissions, roughly from southern solstice to northern solstice. In this study, we extend the SLS4 longitude system to the end of the Cassini mission using a phase tracing method. The new Saturn longitude system (SLS5) organizes the observed SKR maxima around 0° subsolar longitude in both northern and southern hemispheres and can be used to organize other phenomena observed in Saturn's magnetosphere, for example, hot plasma injection events. SKR is modulated like a clock when the main source on the morning side is visible. To convert the observed phase to the clock phase, the phase of the morning side source, we also define a second longitude system SLS5*, which takes the spacecraft position into account based on a simple visibility model.
The Optical Signature of a Bottom Boundary Layer Ventilation Event in the Northern Gulf of Mexico's Hypoxic Zone
Authors: Jolliff Jason K. , Jarosz Ewa , Ladner Sherwin , Smith Travis , Anderson Stephanie , Dykes James
Published: July 2018

Oceanographic observations in the northern Gulf of Mexico captured an unusual combination of atmospheric forcing and shelf frontal dynamics that brought about the surface ventilation of sediment‐laden bottom waters. Colorimetric analysis of in situ optical data indicates a specific turquoise‐white color signature for turbid and low‐oxygen bottom waters that match a coincident shelf‐wide feature detected in Moderate Resolution Imaging Spectroradiometer satellite true color images. The physical processes leading to this ventilation event are simulated using the Coupled Ocean Atmosphere Mesoscale Prediction System, which includes an integrated surface wave model. The combined model‐data analysis suggests that low‐oxygen, bottom water ventilation may occur episodically during boreal spring and summer in the northern Gulf of Mexico following the passage of high‐energy atmospheric systems, and these events may be identified in the historical satellite record based on the unique bottom water optical characteristics.
A More Viscous‐Like Solar Wind Interaction With All the Giant Planets
Authors: Masters A.
Published: July 2018

Identifying and quantifying the different drivers of energy flow through a planetary magnetosphere is crucial for understanding how each planetary system works. The magnetosphere of our own planet is primarily driven externally by the solar wind through global magnetic reconnection, while a viscous‐like interaction with the solar wind involving growth of the Kelvin‐Helmholtz (K‐H) instability is a secondary effect. Here we consider the solar wind‐magnetosphere interaction at all magnetized planets, exploring the implications of diverse solar wind conditions. We show that with increasing distance from the Sun the electric fields arising from reconnection at the magnetopause boundary of a planetary magnetosphere become weaker, whereas the boundaries become increasingly K‐H unstable. Our results support the possibility of a predominantly viscous‐like interaction between the solar wind and every one of the giant planet magnetospheres, as proposed by previous authors and in contrast with the solar wind‐magnetosphere interaction at Earth.
Evidence of Microbursts Observed Near the Equatorial Plane in the Outer Van Allen Radiation Belt
Authors: Shumko Mykhaylo , Turner Drew L. , O'Brien T. P. , Claudepierre Seth G. , Sample John , Hartley D. P. , Fennel Joseph , Blake J. Bernard , Gkioulidou Matina , Mitchell Donald G.
Published: July 2018

We present the first evidence of electron microbursts observed near the equatorial plane in Earth's outer radiation belt. We observed the microbursts on 31 March 2017 with the Magnetic Electron Ion Spectrometer and Radiation Belt Storm Probes Ion Composition Experiment on the Van Allen Probes. Microburst electrons with kinetic energies of 29–92 keV were scattered over a substantial range of pitch angles, and over time intervals of 150–500 ms. Furthermore, the microbursts arrived without dispersion in energy, indicating that they were recently scattered near the spacecraft. We have applied the relativistic theory of wave‐particle resonant diffusion to the calculated phase space density, revealing that the observed transport of microburst electrons is not consistent with the hypothesized quasi‐linear approximation.
Interannual Variability of the Australian Summer Monsoon System Internally Sustained Through Wind‐Evaporation Feedback
Authors: Sekizawa S. , Nakamura H. , Kosaka Y.
Published: July 2018

Interannual variability of Australian summer monsoon (AUSM) activity is hardly forced locally or remotely by tropical sea surface temperature (SST) variability. Despite this lack of SST forcing, convection variability in northern Australia is so strong that it emerges as a distinct peak in climatological variance of convection in austral summer. The present study shows that an internal variability unforced by tropical SST anomaly is dominant in seasonal mean strength of the AUSM system. A mechanism that sustains convection anomaly without SST forcing is also examined. Analysis of latent heat flux reveals that under the climatological monsoon westerlies, the wind‐evaporation feedback in the tropical southeastern Indian Ocean sustains anomalous convection despite a counteracting effect of SST anomalies. The wind anomalies induced by the anomalous AUSM change the subsurface southeastern Indian Ocean, which can contribute to the maintenance of the anomalous convection through weakening the damping effect by SST anomalies.
A New Picture of Fire Extent, Variability, and Drought Interaction in Prescribed Fire Landscapes: Insights From Florida Government Records
Authors: Nowell H. K. , Holmes C. D. , Robertson K. , Teske C. , Hiers J. K.
Published: July 2018

Florida, United States, government records provide a new resource for studying fire in landscapes managed with prescribed fire. In Florida, most fire area (92%) is prescribed. Current satellite fire products, which underpin most air pollution emission inventories, detect only 25% of burned area, which alters airborne emissions and environmental impacts. Moreover, these satellite products can misdiagnose spatiotemporal variability of fires. Overall fire area in Florida decreases during drought conditions as prescribed fires are avoided, but satellite data do not reflect this pattern. This pattern is consistent with prescribed fire successfully reducing overall fire risk and damages. Human management of prescribed fires and fuels can, therefore, break the conventional link between drought and wildfire and play an important role in mitigating rising fire risk in a changing climate. These results likely apply in other regions of the world with similar fire regimes.
Distinct Mechanisms of Ocean Heat Transport Into the Arctic Under Internal Variability and Climate Change
Authors: Oldenburg Dylan , Armour Kyle C. , Thompson LuAnne , Bitz Cecilia M.
Published: July 2018

Northward ocean heat transport (OHT) plays a key role in Arctic climate variability and change. Unforced climate model simulations suggest that at decadal and longer timescales, strengthened Atlantic meridional overturning circulation (AMOC) is correlated with increased OHT into the Arctic. Yet greenhouse gas forced simulations predict increased Arctic OHT while AMOC weakens. Here we partition OHT changes into contributions from dynamic circulation changes and thermodynamic temperature advection, as well as meridional overturning and gyre changes. We find that under decadal‐scale internal variability, strengthened AMOC converges heat in the subpolar gyre; anomalous heat is advected into the Arctic by both time mean circulations and strengthened gyre circulations. Under greenhouse gas forcing, weakened AMOC reduces subpolar gyre heat convergence; yet Arctic OHT increases as mean overturning and strengthened gyre circulations advect warmed surface waters. Thus, caution should be exercised when inferring Arctic OHT from AMOC, as the relationship between OHT and AMOC changes depends on whether they are internally generated or externally forced.
An Explanation for the Nitrous Oxide Layer Observed in the Mesopause Region
Authors: Kelly C. W. , Chipperfield M. P. , Plane J. M. C. , Feng W. , Sheese P. E. , Walker K. A. , Boone C. D.
Published: July 2018

Recent satellite measurements of a layer of enhanced nitrous oxide (N2O) in the mesosphere‐lower thermosphere (MLT) from the Atmospheric Chemistry Experiment‐Fourier Transform Spectrometer have suggested an unexpected, minor high‐altitude production source. Here we report the development of a mechanism and the first model simulations, which can explain the formation of this MLT N2O layer. N2O production occurs primarily via a reaction route involving the excitation of N2 from secondary electrons. Simulations using the Whole Atmosphere Community Climate Model, with external forcing from the Global Airglow model, quantitatively reproduce the observed vertical, latitudinal, and seasonal N2O variations. Sensitivity results indicate that photoelectrons are far more important than previously predicted, causing approximately two thirds of global N2O production in the MLT. Energetic electron precipitation over high latitudes provides the remaining contribution. Solar cycle analysis reveals N2O enhancements of up to ×2 at solar maximum compared to solar minimum.
Observation of Electron Conics by Juno: Implications for Radio Generation and Acceleration Processes
Authors: Louarn P. , Allegrini F. , McComas D. J. , Valek P. W. , Kurth W. S. , André N. , Bagenal F. , Bolton S. , Ebert R. W. , Imai M. , Levin S. , Szalay J. R. , Wilson R. J.
Published: July 2018

Using Juno plasma, electric and magnetic field observations (from JADE, Waves, and MAG instruments), we show that electron conic distributions are commonly observed in Jovian radio sources. The conics are characterized by maximum fluxes at oblique pitch angles, ~20°–30° from the B field, both in the upward and downward directions. They constitute an efficient source of free energy for the cyclotron maser instability. Growth rates of ~3 to 7 × 104 s−1 are obtained for hectometric waves, leading to amplification by e10 with propagation paths of 50–100 km. We show that stochastic acceleration due to interactions with a low‐frequency electric field turbulence located a few 104 km above the ionosphere may form the observed conics. A possible source of turbulence could be inertial Alfvén waves, suggesting a connection between the auroral acceleration and generation of coherent radio emissions.
Morphologic Diversity of Martian Ripples: Implications for Large‐Ripple Formation
Authors: Lapotre M. G. A. , Ewing R. C. , Weitz C. M. , Lewis K. W. , Lamb M. P. , Ehlmann B. L. , Rubin D. M.
Published: July 2018

Large ripples with meter‐scale wavelengths are ubiquitous across Mars. Curiosity's traverse of the Bagnold Dune Field revealed a morphologic diversity of large Martian ripples that helps constrain their formative mechanism. Large ripples develop in isolated fields and on dunes. They form transversely and obliquely to longitudinally to the net sand‐flux direction in unimodally and bimodally distributed very fine to very coarse sand. They have either straight or sinuous crestlines. Inactive ripples are covered with dust, whereas migrating ripples are dust free. Here we present a unifying view of ripples that form in near‐bed sediment‐transport conditions (encompassing fluid‐drag and coarse‐grained ripples) to explain the range of large‐Martian‐ripple morphologies and expand the use of bedforms as environmental indicators.
Widespread Reemergence of Sea Surface Temperature Anomalies in the Global Oceans, Including Tropical Regions Forced by Reemerging Winds
Authors: Byju P. , Dommenget D. , Alexander M. A.
Published: July 2018

Sea surface temperature anomalies (SSTA) in portions of the extratropics are known to recur from one winter to the next without persisting through the intervening summer. Previous studies identified only a limited number of midlatitude regions where this reemergence occurs. Here we find that most of the global oceans exhibit winter‐to‐winter recurrence of SSTA. Indeed, recurrence of SSTA is the default process in the global ocean. Only regions strongly linked to El Niño do not show signs of SST reemergence. In midlatitudes, the temperature anomalies that recur persist below the shallow mixed layer in summer. However, SST recurrence is also found at some tropical locations and appears to be independent of subsurface ocean heat storage. Reemergence at these locations is linked to the recurrence of atmospheric drivers of SSTA, predominantly the wind‐stress forcing. Our results are supported by different ocean data sets and by state‐of‐the‐art climate model simulations.
Saturn's Atmosphere at 1–10 Kilometer Resolution
Authors: Ingersoll Andrew P. , Ewald Shawn P. , Sayanagi Kunio M. , Blalock John J.
Published: July 2018

We present images of Saturn from the final phases of the Cassini mission, including images with 0.5 km per pixel resolution, as high as any Saturn images ever taken. Notable features are puffy clouds resembling terrestrial cumulus, shadows indicating cloud height, dome and bowl shaped cloud structures indicating upwelling and downwelling in anticyclones and cyclones respectively, and filaments, which are thread‐like clouds that remain coherent over distances of 20,000 km. From the coherence of the filaments, we give upper bounds on the diffusivity and kinetic energy dissipation. A radiative transfer analysis by Sanz‐Requena et al. (2018) indicates that methane‐band imagery is most useful in determining cloud and haze properties in the 60–250 mbar pressure range. Our methane‐band imagery finds haze in this pressure range covering 64°‐74°planetocentric latitude. Filaments lie within the haze, and cumulus clouds lie below it, but pressure levels are uncertain below the 250 mbar level.
Extended Survey of Saturn Z‐Mode Wave Intensity Through Cassini's Final Orbits
Authors: Menietti J. D. , Averkamp T. F. , Ye S.‐Y. , Persoon A. M. , Morooka M. W. , Groene J. B. , Kurth W. S.
Published: July 2018

Similar to whistler mode chorus, Z‐mode emission is an efficient diffusive scatterer of electrons possibly resulting in resonant acceleration. We present results of a survey of both the low‐band (5 kHz) and for the first time the high‐band (20 kHz) intensity of these emissions, based on over 11 years of Cassini Radio and Plasma Wave Science instrument data including nine ring‐grazing orbits and two proximal orbits, which occurred at the end of the mission. We distinguish these emissions using density and polarization measurements and calculate the mean intensity as a function of frequency and spatial coordinates. We find that the average low‐band Z‐mode intensity peak is P0 ~7 × 10−8 nT2, while the high‐band peak is much lower at P0 ~10−9 nT2. The spatial distribution of intensity differs for each emission band implying different source regions and perhaps different source mechanisms.
Radial Transport and Plasma Heating in Jupiter's Magnetodisc
Authors: Ng C. S. , Delamere P. A. , Kaminker V. , Damiano P. A.
Published: July 2018

The ion temperature of the magnetosphere of Jupiter derived from Galileo PLS data was observed to increase by about an order of magnitude from 10 to 40 Jupiter radii. This suggests the presence of heating sources that counteract the adiabatic cooling effect of expanding plasma. There have been different attempts of explaining this phenomena, including a magnetohydrodynamic (MHD) turbulent heating model which is based on flux tube diffusion (Saur, Astrophys. J. Lett., 602, L137, 2004). We explore an alternate turbulent heating model based on advection, similar to models commonly used in solar wind heating. Based on spectral analysis of Galileo magnetometer (MAG) data, we find that observed MHD turbulence could potentially provide the required heating to explain some of the increase in plasma temperature. This indicates that advection is a more appropriate way to describe radial transport of plasma in the Jovian magnetosphere beyond 10 Jupiter radii.
How Different Are the Solar Wind‐Interplanetary Conditions and the Consequent Geomagnetic Activity During the Ascending and Early Descending Phases of the Solar Cycles 23 and 24?
Authors: Rawat Rashmi , Echer E. , Gonzalez W. D.
Published: July 2018

The current work investigates the possible solar wind‐interplanetary (SW‐IP) drivers of geomagnetic storms during the longest period (ascending to early descending phases) of the ongoing solar cycle (24). We present a comparative analysis between the two consecutive solar cycles (SCs) 23 and 24. Both the cycles exhibited dual peak feature as observed in the smoothed sunspot numbers SSNsmoothed. For both the cycles, second peak in the SSNsmoothed is higher than the first one as exhibited in the revised SSNsmoothed version. During the entire interval between the ascending to early descending phases (December 2008 to December 2016) of SC‐24, the southward directed Bz and the dawn‐dusk electric field (Ey) were consistently weaker as compared to that during similar interval of SC‐23 (May 1996 to July 2004). The geomagnetic field response represented by Dst index concurrently exhibited similar variation patterns during both the periods. A striking reduction in the intense storm occurrence rate by ∼75% was observed during the considered period of the current solar cycle in comparison to the previous cycle. However, moderate storm occurrence was reduced only by 32% in SC‐24 as compared to SC‐23, which could be attributed to the dominance of corotating interaction regions during SC‐24. No significant difference is found between the intense storm rates around the vernal and autumnal equinoxes in cycle 24, whereas distinct autumnal equinoctial dominance is evident for cycle 23. Further, within each cycle, there is no significant difference in the moderate storm rates around vernal and autumnal equinoxes.
Final Assembly of the Southwestern Central Asian Orogenic Belt as Constrained by the Evolution of the South Tianshan Orogen: Links With Gondwana and Pangea
Authors: Wang Xin‐Shui , Klemd Reiner , Gao Jun , Jiang Tuo , Li Ji‐Lei , Xue Sheng‐Chao
Published: July 2018

The South Tianshan Orogen marks the final assembly of the southwestern Central Asian Orogenic Belt (CAOB) and the Karakum–Tarim cratons. Here we present an integrated mineralogical, geochemical, and geochronological study of the Wuwamen ophiolitic mélange in the South Tianshan to better understand the tectonic evolution of the western CAOB and its links to Gondwana and Pangea. Mantle peridotites with mineral compositions similar to those of abyssal peridotites and basalts with N‐MORB geochemical affinities suggest that the Wuwamen ophiolite was formed in a mid‐ocean ridge setting. Arc‐related gabbro and plagiogranite stocks intruding the mantle peridotites yielded zircon U–Pb ages of 441.1 ± 4.2 and 442.8 ± 2.4 Ma, indicating that the Wuwamen ophiolite got emplaced prior to ~440 Ma. Sericite‐quartz schist from the ophiolitic mélange matrix with abundant 481–319 Ma detrital zircon grains is crosscut by a two‐mica granite dike with a zircon U–Pb age of 321.3 ± 1.7 Ma, thereby constraining the formation of the Wuwamen ophiolitic mélange at ~320 Ma. In conjunction with published data, we propose that the South Tianshan Ocean opened in the late Neoproterozoic and promoted the subsequent separation of microcontinents in the western CAOB from the northeast Gondwana margin during Gondwana assembly. Furthermore, the closure of the South Tianshan Ocean led to the final assembly of the southwestern CAOB and the Karakum–Tarim cratons and their incorporation into Pangea at ~320 Ma.
Paleomagnetism and Geochemistry of ~1144‐Ma Lamprophyre Dikes, Northwestern Ontario: Implications for the North American Polar Wander and Plate Velocities
Authors: Piispa Elisa J. , Smirnov Aleksey V. , Pesonen Lauri J. , Mitchell Roger H.
Published: July 2018

We present new paleomagnetic and geochemical data from a suite of the ~1144‐Ma ultramafic lamprophyre dikes that outcrop in the Canadian Shield northeast of Lake Superior (Ontario, Canada). Nineteen of 22 sampled dikes yielded consistent characteristic remanent magnetization directions of normal (n = 5) and reversed (n = 14) polarity. The primary origin of characteristic remanent magnetization is bolstered by positive baked contact tests and a reversal test. The group mean direction (D = 306.4°, I = 72.1°, α95 = 5.5°, N = 19) obtained from the lamprophyre dikes is statistically indistinguishable from the group mean direction (D = 297.4°, I = 65.5°, α95 = 8.3°, N = 8) previously reported for the nearly coeval ~1142‐Ma Abitibi dikes. The geochemistry of the lamprophyre dikes suggests strong affinity with magmas derived from ocean island basalt‐type mantle sources, consistent with the mantle plume hypothesis for the formation of the ~1.1‐Ga North American Midcontinent Rift. The similarity in age, trend, paleomagnetism, and geochemistry indicates that the lamprophyre and Abitibi dike suites represent the earliest magmatic event associated with the commencement of rifting. The combined mean direction (D = 303.1°, I = 70.2°, α95 = 4.5°, N = 27) corresponds to a paleomagnetic pole at Plat = 55.8°N, Plong = 220.0°E (A95 = 7.3°). The new pole merits the highest classification on the Q‐scale of paleomagnetic reliability and represents a key pole defining the North American apparent polar wander path during the late Mesoproterozoic. Combined with high‐quality data from the ~1108‐Ma Coldwell Complex, our data indicate an equatorward motion of Laurentia at 3.8 ± 1.4 cm/year, comparable with the present‐day velocities of continental plates, before switching to extremely rapid motion between ~1108 and ~1099 Ma.
Transport of Central American Fire Emissions to the U.S. Gulf Coast: Climatological Pathways and Impacts on Ozone and PM2.5
Authors: Wang Sing‐Chun , Wang Yuxuan , Estes Mark , Lei Ruixue , Talbot Robert , Zhu Liye , Hou Pei
Published: July 2018

Fire emissions from Mexico and Central America are transported regularly to the U.S. Gulf Coast every spring under prevailing circulation patterns and affect U.S. air quality. Here we use a GEOS‐Chem passive tracer simulation to develop the climatology of transport pathways of fire emissions over a long‐term time period of April and May 2002–2015 and estimate their adverse air quality effects for urban areas along the Gulf Coast. A conceptual model is presented to describe the transport mechanisms, which involve southerly low‐level jets in the lower troposphere and warm conveyor belt in the middle troposphere. The warm conveyor belts and the southerly low‐level jets explain 31% and 69% of the interannual variability of the mid‐altitude (1.5–6 km) and low‐altitude events (0–1.5 km), respectively. Considering both transport and fire emissions, approximately 9% of the study period (59–88 days of 854 days) were identified as large pollution events during which Central American fire emissions adversely impacted surface air quality at several major urban centers along the Gulf Coast, including Houston and Corpus Christi in TX, New Orleans in LA, Mobile in AL, and Pensacola in FL. Compared to clean maritime flow from the Gulf of Mexico, these events were estimated to result in average enhancements of maximum daily average 8‐hr (MDA8) ozone and daily PM2.5 (fine particulate matter <2.5 μm in diameter) in the Gulf Coast cities of 3–12 ppbv and 2–5 μg/m3, respectively. Only one ozone exceedance day (79 ppbv, on 18 May 2003) was found among the fire‐impact days for the Houston region.
Disruption of the psychiatric risk gene Ankyrin 3 enhances microtubule dynamics through GSK3/CRMP2 signaling
Authors: Garza Jacob C. , Qi Xiaoli , Gjeluci Klaudio , Leussis Melanie P. , Basu Himanish , Reis Surya A. , Zhao Wen Ning , Piguel Nicolas H. , Penzes Peter , Haggarty Stephen J. , Martens Gerard J. , Poelmans Geert , Petryshen Tracey L.
Published: July 2018

The ankyrin 3 gene (ANK3) is a well-established risk gene for psychiatric illness, but the mechanisms underlying its pathophysiology remain elusive. We examined the molecular effects of disrupting brain-specific Ank3 isoforms in mouse and neuronal model systems. RNA sequencing of hippocampus from Ank3+/− and Ank3+/+ mice identified altered expression of 282 genes that were enriched for microtubule-related functions. Results were supported by increased expression of microtubule end-binding protein 3 (EB3), an indicator of microtubule dynamics, in Ank3+/− mouse hippocampus. Live-cell imaging of EB3 movement in primary neurons from Ank3+/− mice revealed impaired elongation of microtubules. Using a CRISPR-dCas9-KRAB transcriptional repressor in mouse neuro-2a cells, we determined that repression of brain-specific Ank3 increased EB3 expression, decreased tubulin acetylation, and increased the soluble:polymerized tubulin ratio, indicating enhanced microtubule dynamics. These changes were rescued by inhibition of glycogen synthase kinase 3 (GSK3) with lithium or CHIR99021, a highly selective GSK3 inhibitor. Brain-specific Ank3 repression in neuro-2a cells increased GSK3 activity (reduced inhibitory phosphorylation) and elevated collapsin response mediator protein 2 (CRMP2) phosphorylation, a known GSK3 substrate and microtubule-binding protein. Pharmacological inhibition of CRMP2 activity attenuated the rescue of EB3 expression and tubulin polymerization in Ank3-repressed cells by lithium or CHIR99021, suggesting microtubule instability induced by Ank3 repression is dependent on CRMP2 activity. Taken together, our data indicate that ANK3 functions in neuronal microtubule dynamics through GSK3 and its downstream substrate CRMP2. These findings reveal cellular and molecular mechanisms underlying brain-specific ANK3 disruption that may be related to its role in psychiatric illness.
Investigation of recombination-intense viral groups and their genes in the Earth’s virome
Authors: Meier-Kolthoff Jan P. , Uchiyama Jumpei , Yahara Hiroko , Paez-Espino David , Yahara Koji
Published: July 2018

Bacteriophages (phages), or bacterial viruses, are the most abundant and diverse biological entities that impact the global ecosystem. Recent advances in metagenomics have revealed their rampant abundance in the biosphere. A fundamental aspect of bacteriophages that remains unexplored in metagenomic data is the process of recombination as a driving force in evolution that occurs among different viruses within the same bacterial host. Here, we systematically examined signatures of recombination in every gene from 211 species-level viral groups in a recently obtained dataset of the Earth’s virome that contain corresponding information on the host bacterial species. Our study revealed that signatures of recombination are widespread (84%) among the diverse viral groups. We identified 25 recombination-intense viral groups, widely distributed across the viral taxonomy, and present in bacterial species living in the human oral cavity. We also revealed a significant inverse association between the recombination-intense viral groups and Type II restriction endonucleases, that could be effective in reducing recombination among phages in a cell. Furthermore, we identified recombination-intense genes that are significantly enriched for encoding phage morphogenesis proteins. Changes in the viral genomic sequence by recombination may be important to escape cleavage by the host bacterial immune systems.
L-tyrosine supplementation does not ameliorate skeletal muscle dysfunction in zebrafish and mouse models of dominant skeletal muscle α-actin nemaline myopathy
Authors: Messineo Adriana M. , Gineste Charlotte , Sztal Tamar E. , McNamara Elyshia L. , Vilmen Christophe , Ogier Augustin C. , Hahne Dorothee , Bendahan David , Laing Nigel G. , Bryson-Richardson Robert J. , Gondin Julien , Nowak Kristen J.
Published: July 2018

L-tyrosine supplementation may provide benefit to nemaline myopathy (NM) patients, however previous studies are inconclusive, with no elevation of L-tyrosine levels in blood or tissue reported. We evaluated the ability of L-tyrosine treatments to improve skeletal muscle function in all three published animal models of NM caused by dominant skeletal muscle α-actin (ACTA1) mutations. Highest safe L-tyrosine concentrations were determined for dosing water and feed of wildtype zebrafish and mice respectively. NM TgACTA1D286G-eGFP zebrafish treated with 10 μM L-tyrosine from 24 hours to 6 days post fertilization displayed no improvement in swimming distance. NM TgACTA1D286G mice consuming 2% L-tyrosine supplemented feed from preconception had significant elevations in free L-tyrosine levels in sera (57%) and quadriceps muscle (45%) when examined at 6–7 weeks old. However indicators of skeletal muscle integrity (voluntary exercise, bodyweight, rotarod performance) were not improved. Additionally no benefit on the mechanical properties, energy metabolism, or atrophy of skeletal muscles of 6–7 month old TgACTA1D286G and KIActa1H40Y mice eventuated from consuming a 2% L-tyrosine supplemented diet for 4 weeks. Therefore this study yields important information on aspects of the clinical utility of L-tyrosine for ACTA1 NM.
Positive selection and climatic effects on MHC class II gene diversity in hares (Lepus capensis) from a steep ecological gradient
Authors: Awadi Asma , Ben Slimen Hichem , Smith Steve , Knauer Felix , Makni Mohamed , Suchentrunk Franz
Published: July 2018

In natural populations, allelic diversity of the major histocompatibility complex (MHC) is commonly interpreted as resulting from positive selection in varying spatiotemporal pathogenic landscapes. Composite pathogenic landscape data are, however, rarely available. We studied the spatial distribution of allelic diversity at two MHC class II loci (DQA, DQB) in hares, Lepus capensis, along a steep ecological gradient in North Africa and tested the role of climatic parameters for the spatial distribution of DQA and DQB proteins. Climatic parameters were considered to reflect to some extent pathogenic landscape variation. We investigated historical and contemporary forces that have shaped the variability at both genes, and tested for differential selective pressure across the ecological gradient by comparing allelic variation at MHC and neutral loci. We found positive selection on both MHC loci and significantly decreasing diversity from North to South Tunisia. Our multinomial linear models revealed significant effects of geographical positions that were correlated with mean annual temperature and precipitation on the occurrence of protein variants, but no effects of co-occurring DQA or DQB proteins, respectively. Diversifying selection, recombination, adaptation to local pathogenic landscapes (supposedly reflected by climate parameters) and neutral demographic processes have shaped the observed MHC diversity and differentiation patterns.
Experience of the signaller explains the use of social versus personal information in the context of sentinel behaviour in meerkats
Authors: Rauber R. , Manser M. B.
Published: July 2018

To maximise foraging opportunities while simultaneously avoiding predation, group-living animals can obtain personal information on food availability and predation risk and/or rely on social information provided by group members. Although mainly associated with low costs of information acquisition, social information has the potential to be irrelevant or inaccurate. In this study we use playbacks of individually distinct sentinel calming calls produced during sentinel behaviour, a form of coordinated vigilance behaviour, to show that meerkats (Suricata suricatta) discriminate between social information provided by different sentinels and adjust their personal vigilance behaviour according to the individual that is played back. We found that foraging group members acquired the lowest amounts of personal information when hearing social information provided by experienced individuals that act as sentinels most often in their group and littermates. Our study shows that social information can be flexibly used in the context of sentinel behaviour in order to optimize the trade-off between foraging and vigilance behaviours dependent on discrimination among signallers. We also provide novel evidence that the experience of sentinels rather than their age or dominance status is the main factor affecting the extent to which individuals use social information.
Comparison of Optical Coherence Tomography Angiography to Indocyanine Green Angiography and Slit Lamp Photography for Corneal Vascularization in an Animal Model
Authors: Stanzel Tisha P. , Devarajan Kavya , Lwin Nyein C. , Yam Gary H. , Schmetterer Leopold , Mehta Jodhbir S. , Ang Marcus
Published: July 2018

Corneal neovascularization (CoNV) could be treated by novel anti-angiogenic therapies, though reliable and objective imaging tools to evaluate corneal vasculature and treatment efficacy is still lacking. Optical coherence tomography angiography (OCTA) –currently designed as a retinal vascular imaging system— has been recently adapted for anterior-segment and showed good potential for successful imaging of CoNV. However, further development requires an animal model where parameters can be studied more carefully with histological comparison. Our study evaluated the OCTA in suture-induced CoNV in a rabbit model compared to indocyanine green angiography (ICGA) and slit-lamp photography (SLP). Overall vessel density measurements from OCTA showed good correlation with ICGA (0.957) and SLP (0.992). Vessels density by OCTA was higher than ICGA and SLP (mean = 20.77 ± 9.8%, 15.71 ± 6.28% and 17.55 ± 8.36%, respectively, P < 0.05). OCTA was able to depict CoNV similarly to SLP and ICGA, though it could better detect small vessels. Moreover, the depth and growth of vessels could be assessed using en-face and serial-scans. This study validated the OCTA in a rabbit model as a useful imaging tool for translational studies on CoNV. This may contribute to further studies on OCTA for anterior-segment including serial evaluation of emerging anti-angiogenic therapies.
Galectin-1 Restricts Vascular Smooth Muscle Cell Motility Via Modulating Adhesion Force and Focal Adhesion Dynamics
Authors: Tsai Min-Shao , Chiang Ming-Tsai , Tsai Dong-Lin , Yang Chih-Wen , Hou Hsien-San , Li Yi-Ru , Chang Po-Chiao , Lin Heng-Huei , Chen Huan-Yuan , Hwang Ing-Shouh , Wei Pei-Kuen , Hsu Chiao-Po , Lin Kuo-I , Liu Fu-Tong , Chau Lee-Young
Published: July 2018

Vascular smooth muscle cell (VSMC) migration play a key role in the development of intimal hyperplasia and atherosclerosis. Galectin-1 (Gal-1) is a redox-sensitive β-galactoside-binding lectin expressed in VSMCs with intracellular and extracellular localizations. Here we show that VSMCs deficient in Gal-1 (Gal-1-KO) exhibited greater motility than wild type (WT) cells. Likewise, Gal-1-KO-VSMC migration was inhibited by a redox-insensitive but activity-preserved Gal-1 (CSGal-1) in a glycan-dependent manner. Gal-1-KO-VSMCs adhered slower than WT cells on fibronectin. Cell spreading and focal adhesion (FA) formation examined by phalloidin and vinculin staining were less in Gal-1-KO-VSMCs. Concomitantly, FA kinase (FAK) phosphorylation was induced to a lower extent in Gal-1-KO cells. Analysis of FA dynamics by nocodazole washout assay demonstrated that FA disassembly, correlated with FAK de-phosphorylation, was faster in Gal-1-KO-VSMCs. Surface plasmon resonance assay demonstrated that CSGal-1 interacted with α5β1integrin and fibronectin in a glycan-dependent manner. Chemical crosslinking experiment and atomic force microscopy further revealed the involvement of extracellular Gal-1 in strengthening VSMC-fibronectin interaction. In vivo experiment showed that carotid ligation-induced neointimal hyperplasia was more severe in Gal-1-KO mice than WT counterparts. Collectively, these data disclose that Gal-1 restricts VSMC migration by modulating cell-matrix interaction and focal adhesion turnover, which limits neointimal formation post vascular injury.
The Association between Red Blood Cell Distribution Width and Sarcopenia in U.S. Adults
Authors: Kim Junghoon , Im Jeong-Soo , Choi Chang Hyu , Park Chul Hyun , Lee Jae Ik , Son Kuk Hui , Choi Yoon-Hyeong
Published: July 2018

One pathophysiological sign of sarcopenia is chronic inflammation. Given that levels of red blood cell distribution width (RDW) are increased in chronic inflammation, we evaluated the association between increased RDW and sarcopenia among adults in the general U. S. population and analyzed data from 11,761 participants from the National Health and Nutrition Examination Survey (NHANES) 1999–2006. Sarcopenia was defined as an appendicular skeletal muscle mass (ASM) divided by weight (%) that was less than one standard deviation (SD) below the mean of young adults. The odds ratios (ORs) and confidence intervals (CIs) for sarcopenia were calculated across RDW quartiles after adjusting for confounding factors. Elevated RDW levels were significantly associated with sarcopenia after adjusting for age, sex, race, education, household income, smoking, physical activity, hypertension, diabetes, cardiovascular disease, C-reactive protein, and hemoglobin (OR of highest quartile: 1.72 (95% CI: 1.43, 2.06)). Further, in a model stratified by obesity, an elevated RDW was associated with sarcopenia in the overweight and obese group, but not in the normal weight group. Our study shows that elevated RDW is associated with sarcopenia, and this association is particularly strong in people who are overweight and obese.
Blue pigmentation of neustonic copepods benefits exploitation of a prey-rich niche at the air-sea boundary
Authors: Rahlff Janina , Ribas-Ribas Mariana , Brown Scott M. , Mustaffa Nur Ili Hamizah , Renz Jasmin , Peck Myron A. , Bird Kimberley , Cunliffe Michael , Melkonian Katharina , Zappa Christopher J.
Published: July 2018

The sea-surface microlayer (SML) at the air-sea interface is a distinct, under-studied habitat compared to the subsurface and copepods, important components of ocean food webs, have developed key adaptations to exploit this niche. By using automated SML sampling, high-throughput sequencing and unmanned aerial vehicles, we report on the distribution and abundance of pontellid copepods in relation to the unique biophysicochemical signature of the SML. We found copepods in the SML even during high exposure to sun-derived ultraviolet radiation and their abundance was significantly correlated to increased algal biomass. We additionally investigated the significance of the pontellids’ blue pigmentation and found that the reflectance peak of the blue pigment matched the water-leaving spectral radiance of the ocean surface. This feature could reduce high visibility at the air-sea boundary and potentially provide camouflage of copepods from their predators.
Spectroscopy-based characterization of Hb–NO adducts in human red blood cells exposed to NO-donor and endothelium-derived NO
Authors: Dybas Jakub , Berkowicz Piotr , Proniewski Bartosz , Dziedzic-Kocurek Katarzyna , Stanek Jan , Baranska Malgorzata , Chlopicki Stefan , Marzec Katarzyna M.
Published: July 2018

The work presents the complementary approach to characterize the formation of various Hb species inside isolated human RBCs exposed to NO, with a focus on the formed Hb–NO adducts.
Continuous amperometric hydrogen gas sensing in ionic liquids
Authors: Tang Yongan , He Jianxin , Gao Xiaoli , Yang Tianbao , Zeng Xiangqun
Published: July 2018

Continuous and real-time ionic liquid based hydrogen gas sensor with high sensitivity, selectivity, speed, accuracy, repeatability and stability.
Carbon tape as a convenient electrode material for electrochemical paper-based microfluidic devices (ePADs)
Authors: Gomez Federico J. V. , Reed Paige A. , Gonzalez Casamachin Diego , Rivera de la Rosa Javier , Chumanov George , Silva Maria Fernanda , Garcia Carlos D.
Published: July 2018

ePADs represent an innovative and versatile platform for fluid handling and analysis.
Ni-Catalyzed cross-coupling of aryl thioethers with alkyl Grignard reagents via C–S bond cleavage
Authors: Zhu Dan , Shi Lei
Published: July 2018

A Ni-catalyzed cross-coupling of aryl thioethers with alkyl Grignard reagents, accompanied by the cleavage of the C(aryl)–SMe bond, has been presented.
Reprogramming axial ligands facilitates the self-assembly of a platinum(iv) prodrug: overcoming drug resistance and saferin vivodelivery of cisplatin
Authors: Fang Tao , Ye Zhijian , Wu Jiaping , Wang Hangxiang
Published: July 2018

We herein reprogrammed axial ligands of platinum(iv) prodrugs, conferring the constructed prodrug entities with the ability to self-assemble in aqueous solution.