Miracle-dz/UniFAR-FTUs huggingface dataset:
Dichotomy in mode propagation of coseismic ionospheric disturbance: Observations from 11 April 2012 Indian Ocean earthquake

The ionosphere response to the great intraplate Indian Ocean earthquake of 11 April 2012 (Mw 8.6) and its largest aftershock (Mw 8.2) is analyzed using GPS‐aided total electron content (TEC) measurements. Data from the dense GPS networks, SuGAr (Sumatran GPS Array) and the permanent Andaman‐Nicobar array, formed the near‐field observations at distances 250–1200 km from the epicenter. Stations such as IISC, DGAR, and few others provided measurements over 2000 km from the epicenter. The coseismic ionospheric disturbances (CIDs) with a propagation velocity of 930–1262 m/s, equals the speeds of the shock acoustic waves, arrive within 10–18 min after the earthquake occurrence. The observed phenomenon of CID splitting into two modes, north and south of the epicenter, is akin to the well‐documented effects of anisotropy on wave propagation. Closer to the epicenter, to its south, the propagation velocity of CID is ~1 km/s, and farther southeast of the network the velocity reduces to 500–600 m/s. In contrast, toward Andaman in the north, the CID propagation velocity increases to 2–3.5 km/s. The zenith angle of the line of sight between the GPS receiver and satellite appears to influence the amplitude of the TEC fluctuations. The anomalous azimuthal variation of the Rayleigh wave radiation pattern best explains the observed N‐S asymmetry of CID.
SATELLITE OBSERVATIONS OF ENERGETIC HEAVY IONS DURING A GEOMAGNETIC STORM.

Large fluxes of energetic heavy ions (M / q ≈ 16) were observed in the inner magnetosphere during the geomagnetic storm of December 17, 1971. The observations were made by a set of energetic-ion mass spectrometers covering the energy range 0.7–12 kev on board the polar-orbiting satellite 1971-089A (800-km altitude, ≈0300 LT). Significant heavy-ion fluxes were observed for a period of approximately 48 hours during the main phase of the storm. The heavy-ion fluxes frequently exceeded the proton fluxes in the 0.7- to 12-kev energy range. The heavy-ion spectrums were highly variable and frequently contained a peak of several kev. The heavy ions were observed over a wide latitudinal range (2.4 ≲ L ≲ 9) and generally extended to somewhat lower latitudes than the protons. The peak energy flux of these ions was approximately 0.4 erg/cm² sec ster, which is substantial in terms of expected observable ionospheric effects. They may also contribute significantly to the storm-time magnetic-field depression (Dst), since at the same flux they represent an energy density greater by a factor of 4 than that of the protons.
Two case studies of winter continental‐type water and mixed‐phase stratocumuli over the sea 2. Absorption of solar radiation

[1] We have carried out airborne experiments on cloud-radiation interactions for wintertime boundary layer clouds over the East China Sea and the Japan Sea in January 1999 as part of the Japanese Cloud and Climate Study (JACCS) program. By means of collocated and synchronized flights of two instrumented aircraft, flying above and below the cloud layer, respectively, we directly measured the visible and near-infrared (IR) solar absorption for two cases of stratiform clouds: one featuring supercooled water stratocumulus cloud polluted by continental aerosols observed on 21 January and one featuring highly inhomogeneous, mixed-phase stratocumulus clouds observed on 30 January. The former cloud layer, with a geometrical thickness of about 500 m (optical thickness of about 30), absorbed substantial (6%) and significant (21%) amounts of solar radiation in the visible and near-IR bands, respectively. For the latter mixed-phase cloud, on an average over a long flight distance, the visible-band solar absorption was almost zero, while the near-IR-band absorption was about 24% for the cloud layer with a mean thickness of 1.3 km. The results indicate no sign of the so-called anomalous solar absorption for either cloud case. Through radiative transfer simulations for reasonable aerosol-cloud models, along with back trajectory analysis, the visible-band solar absorption by the aerosol-polluted cloud on 21 January was attributed to absorbing aerosols from continental East Asia. The simulation study also suggests that anthropogenic water-soluble aerosols, as well as soil-dust particles, may cause appreciable visible absorption by cloud particles, resulting in an enhanced solar heating in the boundary layer cloud.
Latitudinal change of remineralization ratios in the oceans and its implication for nutrient cycles

A new three‐end‐member mixing model is introduced to obtain remineralization ratios of organic matter in the water column. Remineralization ratios (P/N/Corg/−O2) of organic matter in the deep water column change systematically from the northern Atlantic to the Southern Oceans, then to the equatorial Indian and the northern Pacific oceans, more or less along the global ocean circulation route of deep water. Average remineralization ratios of organic matter for the northern Atlantic Ocean are P/N/Corg/−O2 = 1/(16 ± 1)/(73 ± 8)/(137 ± 7), and for the Southern Oceans P/N/Corg/−O2 = 1/(15 ± 1)/(80 ± 3)/(133 ± 5). Those values are similar to the traditional Redfield ratios of P/N/Corg/−O2 = 1/16/106/138 for marine plankton, except for the low Corg/P ratio. Average remineralization ratios for the equatorial Indian Ocean are P/N/Corg/−O2 = 1/(10 ± 1)/(94 ± 5)/(130 ± 7), and for the northern Pacific Ocean P/N/Corg/−O2 = 1/(13 ± 1)/(124 ± 11)/(162 ± 11). The apparent low N/P ratio for both ocean basins suggests that organic nitrogen was converted partly into gaseous N2O and N2 by bacteria through nitrification/denitrification processes in a low‐oxygen or reducing microenvironment of organic matter throughout the oxygenated water column. The actual N/P ratio of remineralized organic matter is probably around 15 ± 1. The −O2/Corg ratio of remineralized organic matter also decreases systematically along the global ocean circulation route of deep water, indicating changes in relative proportions of biomolecules such as lipids, proteins, nucleic acids, and carbohydrates. No temporal trends of remineralization ratios are detected when comparing the results obtained by GEOSECS and WOCE data sets.
The active part of Charlie‐Gibbs Fracture Zone: A study using sonar and other geophysical techniques

A short survey with Gloria side-scan sonar and other geophysical instruments has revealed new information about Charlie-Gibbs fracture zone between 29° and 36°W. The traces of two transform faults have been clearly delineated. They fit small circles about the pole of rotation with an rms error of only about 1 km, but they do not always follow the deepest parts of the transform valleys. The transforms are joined by a short spreading center at 31°45′W. The median transverse ridge appears to have been produced by normal seafloor spreading at this center and bears identifiable Vine-Matthews magnetic anomalies. A transverse ridge along the eastern inactive part of the northern transform may be an intrusive feature. Considerable thicknesses of sediment appear to have been deposited in the northern transform valley from Norwegian Sea overflow water passing through the fracture zone, but transverse ridges have prevented the sediment reaching the southern valley.
Nuciferine induces autophagy to relieve vascular cell adhesion molecule 1 activation via repressing the Akt/mTOR/AP1 signal pathway in the vascular endothelium

Pro-inflammatory factor-associated vascular cell adhesion molecule 1 (VCAM1) activation initiates cardiovascular events. This study aimed to explore the protective role of nuciferine on TNFα-induced VCAM1 activation. Nuciferine was administrated to both high-fat diet (HFD)-fed mice and the TNFα-exposed human vascular endothelial cell line. VCAM1 expression and further potential mechanism(s) were explored. Our data revealed that nuciferine intervention alleviated VCAM1 activation in response to both high-fat diet and TNFα exposure, and this protective effect was closely associated with autophagy activation since inhibiting autophagy by either genetic or pharmaceutical approaches blocked the beneficial role of nuciferine. Mechanistical studies revealed that Akt/mTOR inhibition, rather than AMPK, SIRT1, and p38 signal pathways, contributed to nuciferine-activated autophagy, which further ameliorated TNFα-induced VCAM1 via repressing AP1 activation, independent of transcriptional regulation by IRF1, p65, SP1, and GATA6. Collectively, our data uncovered a novel biological function for nuciferine in protecting VCAM1 activation, implying its potential application in improving cardiovascular events.
An ASM-HEMT for Large-Signal Modeling of GaN HEMTs in High-Temperature Applications

This paper reports a temperature-dependent ASM-HEMT for modeling GaN HEMTs at elevated temperatures. Modifications to the standard ASM-HEMT were developed to accurately capture the DC and RF measurements collected at varying chuck temperatures. Several results are reported which validate the model including DC-IV, pulsed-IV, scattering-parameter, and load-pull measurements. The model is then used to extrapolate the performance of the GaN HEMT to twice the operating temperature at which the model was validated. This work could be useful for understanding and modeling GaN HEMTs in high-temperature environment applications.
Linking forest cover, soil erosion and mire hydrology to late-Holocene human activity and climate in NW Spain

Forest clearance is one of the main drivers of soil erosion and hydrological changes in mires, although climate may also play a significant role. Because of the wide range of factors involved, understanding these complex links requires long-term multi-proxy approaches and research on the best proxies to focus. A peat core from NW Spain (Cruz do Bocelo mire), spanning the last ~3000 years, has been studied at high resolution by physical (density and loss on ignition (LOI)), geochemical (elemental composition) and palynological (pollen and non-pollen palynomorphs) analyses. Proxies related to mineral matter fluxes from the catchment (lithogenic tracers, Glomus and Entorrhiza), rainfall (Bromine), mire hydrology (HdV-18), human pressure (Cerealia-type, nitrophilous taxa and coprophilous fungi) and forest cover (mesophilous tree taxa) were the most useful to reconstruct the evolution of the mire and its catchment. Forest clearance for farming was one of the main drivers of environmental change from at least the local Iron Age (~2685 cal. yr BP) onwards. The most intense phase of deforestation occurred during Roman and Germanic times and the late Middle Ages. During these phases, the entire catchment was affected, resulting in enhanced soil erosion and severe hydrological modifications of the mire. Climate, especially rainfall, may have also accelerated these processes during wetter periods. However, it is noteworthy that the hydrology of the mire seems to have been insensitive to rainfall variations when mesophilous forest dominated. Abrupt changes were only detected once intense forest clearance commenced during the Iron Age/Roman transition (~2190 cal. yr BP) phase, which represented a tipping point in catchment’s ability to buffer impacts. Overall, our findings highlight the importance of studying ecosystems’ long-term trajectories and catchment-wide processes when implementing mire habitat protection measures.
Grain Shape Effects on Settling Rates: A Reply

Janke has misunderstood the basic objective of our study (Komar and Reimers 1978); perhaps we should have discussed it at greater length. Our purpose obviously was not to test all of the shape factors that have been proposed in the literature, at latest count there being at least a dozen. Instead, the objective was to consider only those shape factors that have a firm foundation in fluid mechanics and the evaluation of the drag on a particle settling in a fluid. This limited our analysis to only two, the Corey Shape Factor [CSF] and the Wadell Sphericity [WSF]. Both were clearly formulated with fluid drag considerations in mind (Wadell 1932, 1933; Corey 1949; McNown and Malaika 1960). Sneed and Folk (1958) present the best explanation for the derivation of CSF, although they express it in terms of a "maximum projection sphericity. " It is for this reason that we did not include considerations of the shape factors proposed by Janke (1966) or those proposed by others based purely upon particle geometry. Although Janke (1966) couches his derivations in fluid mechanics terminology, in the end his development and formulae are completely empirical with no real physical foundations.
The timing of spring migration in trans-Saharan migrants: a comparison between Ottenby, Sweden and Capri, Italy

Some migratory birds have advanced their spring arrival to Northern Europe, possibly by increasing the speed of migration through Europe in response to increased temperature en route. In this paper we compare the phenology of spring arrival of seven trans-Saharan migrants along their migration route and test for patterns indicating that migration speed varied over the season using long-term data collected on the Italian island of Capri and at Ottenby Bird Observatory, Sweden. There was a linear relationship between median arrival dates on Capri and at Ottenby. The slope was not significantly different from one. On average, the seven species arrived 15 days later at Ottenby compared to Capri. There was a (non-significant) negative relationship between the species-specific arrival dates at Capri and the differences in median arrival dates between Capri and Ottenby, possibly indicating a tendency towards faster migration through Europe later in the season. To what extent different species are able to speed up their migration to benefit from the advancement of spring events is unknown. (Less)
The attenuation rates of ocean waves in the marginal ice zone

During field operations in the Greenland and Bering Seas in 1978, 1979 and 1983, a number of experiments were carried out in which wave energy was measured along a line of stations running from the open sea deep into an icefield. Wave buoys in the water and accelerometer packages on floes were the instruments employed, with airborne vertical photography to supply information on floe size distribution. It was found that the decay of waves is exponential, with a decay coefficient which generally increases with frequency except for a roll-over at the highest frequencies. The observations can be fitted reasonably well to a theory of one-dimensional scattering.
Reconstructing history, grounding claims to space: history, memory, and displacement in the Great Limpopo Transfrontier Park

The recent creation of Mozambique's Limpopo National Park (LNP) and its integration into the larger Great Limpopo Transfrontier Park (GLTP) promise to effect profound political, social, and ecological changes. These range from removing sections of the international border fence and restocking wildlife in the LNP to the planned relocation of several thousand people living within the park. These transformations have inspired complex, conflicting excavations of the past. This paper investigates how history and memory are deployed as strategic political resources to justify competing claims to space, in this case the rural village of Massingir Velho slated for relocation and the larger GLTP/LNP. Official GLTP history strategically rationalizes the creation of a transnational park that is rich in wildlife and tourist opportunities and a vehicle for addressing multiple past violences. Residents of Massingir Velho who are critical of the planned relocation reconstruct a strikingly different history. They draw on intimate place-based and lived memories of two prior displacements to question the legitimacy of the current round of relocation. In short, historical excavations and reconstructions ground claims to space to both reinvent it, for example in the form of a transfrontier park, and to contest such spatial transformations. The mobilization of history, in short, actively shapes present and future spaces and possibilities.
Seismic velocity structure and composition of the continental crust: A global view

Seismic techniques provide the highest-resolution measurements of the structure of the crust and have been conducted on a worldwide basis. We summarize the structure of the continental crust based on the results of seismic refraction profiles and infer crustal composition as a function of depth by comparing these results with high-pressure laboratory measurements of seismic velocity for a wide range of rocks that are commonly found in the crust. The thickness and velocity structure of the crust are well correlated with tectonic province, with extended crust showing an average thickness of 30.5 km and orogens an average of 46.3 km. Shields and platforms have an average crustal thickness nearly equal to the global average. We have corrected for the nonuniform geographical distribution of seismic refraction profiles by estimating the global area of each major crustal type. The weighted average crustal thickness based on these values is 41.1 km. This value is 10% to 20% greater than previous estimates which underrepresented shields, platforms, and orogens. The average compressional wave velocity of the crust is 6.45 km/s, and the average velocity of the uppermost mantle (Pn velocity) is 8.09 km/s. We summarize the velocity structure of the crust at 5-km depth intervals, both in the form of histograms and as an average velocity-depth curve, and compare these determinations with new measurements of compressional wave velocities and densities of over 3000 igneous and metamorphic rock cores made to confining pressures of 1 GPa. On the basis of petrographic studies and chemical analyses, the rocks have been classified into 29 groups. Average velocities, densities, and standard deviations are presented for each group at 5-km depth intervals to crustal depths of 50 km along three different geotherms. This allows us to develop a model for the composition of the continental crust. Velocities in the upper continental crust are matched by velocities of a large number of lithologies, including many low-grade metamorphic rocks and relatively silicic gneisses of amphibolite facies grade. In midcrustal regions, velocity gradients appear to originate from an increase in metamorphic grade, as well as a decrease in silica content. Tonalitic gneiss, granitic gneiss, and amphibolite are abundant midcrustal lithologies. Anisotropy due to preferred mineral orientation is likely to be significant in upper and midcrustal regions. The bulk of the lower continental crust is chemically equivalent to gabbro, with velocities in agreement with laboratory measurements of mafic granulite. Garnet becomes increasingly abundant with depth, and mafic garnet granulite is the dominant rock type immediately above the Mohorovicic discontinuity. Average compressional wave velocities of common crustal rock types show excellent correlations with density. The mean crustal density calculated from our model is 2830 kg/m3, and the average SiO2 content is 61.8%.
Energetics of the Kuroshio Extension at 35°N, 152°E

Abstract A simplistic interpretation of eddy heat fluxes from a two-year current meter mooring deployment in the Kuroshio Extension leads to the conclusion that the eddy field is denying at 152°E, contradicting observations from the surface to 300 m that indicate the region to be one of steady or growing eddy energy. Thus, a simplified version of the method used by Hall to construct the velocity field of the current from the moored data has been used to examine the baroclinic and barotropic energy conversions in the cyclonic and anticyclonic portions of the current, for both geographic and ‘stream’ coordinates. Although the error bars are large, in stream coordinates significant conversions of mean to eddy potential energy occur on the anticyclonic side of the current at both 350 and 625 dbar, with smaller average conversions of eddy to mean energy over the cold portion. Barotropic conversions in this coordinate system are small, but qualitatively the calculated Reynolds stresses agree with previous obser.
Seasonal variation of the O/N2 ratio in the F 1 region

Incoherent scatter measurements of the altitude variation of the ratio of atomic ions (O+) to electrons are presented that supplement earlier ion composition measurements made in the region 130–240 km at the Millstone Hill radar. In this paper, we use an improved technique for recovering the ratio ρ = [O+]/Ne from the observations. No assumptions need be made about the electron temperature, and we allow for the variation of the measured parameters within the height interval occupied by the exploring pulse. As in earlier measurements at Millstone Hill, a definite seasonal variation in ρ was found with O+, extending to lower altitudes in winter than in summer. These ratios are used, together with measurements of the electron density and relevant theory, to derive the corresponding seasonal variation in the ratio of O to N2. Finally, the seasonal variation in O/N2 obtained here is compared with measurements of O/N2 made by rocket- and satellite-borne mass spectrometers.
High-resolution measurement of phase-shift amplitude and numeric object phase calculation

A new method for measuring the object independent irradiance function for combined Gray-code and phase-shift 3-D measurement systems is presented. The irradiance functions of the projected sinusoidal patterns are measured with high resolution in the phase space without leaving the signal chain of the measurement system. This preserves the system specific distortions of the projected intensity functions. The system specific irradiance functions can be used to compute the object phase numerically. It can be shown that the systematic error of phase shift measurement caused by non sinusoidal phase-shift patterns and phase shifter mis-calibration can be reduced significantly.
Numerical Solution of the Boussinesq Equation for Aquifer‐Stream Interaction

An efficient numerical technique is used to obtain solutions of the Boussinesq equation for problems of groundwater recession and groundwater flow in response to changes in stream stage. Comparison of the numerical results with the analytical solution of Boussinesq [1904] attests to the accuracy of the former. The solution of a recession problem indicates that the form of the Werner and Sundquist [1951] model of groundwater discharge recession is appropriate. The solution of a problem involving changing boundary conditions on an aquifer because of a flood wave provides data relative to groundwater outflow. A comparison with the results of Cooper and Rorabaugh [1963] evaluates the applicability of a linear model of unconfined flow.
Geology of Mumbai and Surrounding Areas and its Position in the Deccan Volcanic Stratigraphy, India

Field data reveal that the lava flows in Mumbai and surrounding areas erupted after the rifting of the main plateau basalts of the Deccan Volcanic Province. Majority of the lava flows occur as subaqueous lavas forming hyaloclastites, spilitic pillow lavas and partially subaqueous and subaerial flows. The basic lavas are associated with rhyolitic flows and contemporaneous intrusions of basic and trachytic magmas forming hybrid rocks of monzonitic and dioritic variety. It has been shown that petrochemically the basic magma of the area is very different from the magma types associated with the mainland horizontal flood basalts ofthe Deccan Volcanic Province. The basic rocks of the Mumbai-Salsette area show lower concentrations of Cr, Ni, Y, V and Ti; and higber concentrations of K, Rb, Ba, Zr and Nb. Majority of these samples contain similar concentrations of phosphorus except for three Salsette samples which show unusual high values. The volcanics of the Mumbai-Salsette area are classified as forming the Salsette Subgroup with three Formations viz., Mumbai Island, Madh-Utan and Manori.