Miracle-dz/UniFAR-FTUs huggingface dataset:
High‐resolution (104 years) deep‐sea foraminiferal stable isotope records of the Eocene‐Oligocene climate transition

We have constructed high-resolution (104– 105 years) benthic foraminiferal δ13C and δ18O records for the upper Eocene through lower Oligocene of two pelagic sequences, Deep Sea Drilling Project (DSDP) Site 522 in the Angola Basin, South Atlantic Ocean, and Ocean Drilling Program (ODP) Site 744 in the southern Indian Ocean. These records provide improved constraints on both the timing and magnitude of marine oxygen and carbon isotope events from 30 to 35 Ma. The oxygen isotope records indicate that the ubiquitous δ18O increase (Oi-1), which marks the rapid expansion of continental ice sheets and a minimum of 3° to 4°C of cooling of bottom waters in the earliest Oligocene (33.6 Ma), occurred in <350 kyr. More than half the transition occurred over the final 40–50 kyr. This period of lower temperatures and widespread continental glaciation persisted for roughly 400 kyr (i.e., the duration of magnetochron C13n). These records also indicate that this interval was characterized by at least two ∼ 100-kyr waxing and waning cycles (Oi-1a and Oi-1b) and possibly several higher-frequency events. The benthic foraminiferal δ13C records show a positive 0.8‰ excursion that is nearly isochronous with the Oi-1 oxygen isotope increase. Similar magnitude δ13C increases at other sites indicate this was a global phenomenon suggestive of an unusually large perturbation to the carbon cycle. This excursion was followed by smaller amplitude δ13C oscillations with periods of roughly ∼400 kyr. We suspect that the ubiquitous Oi-1 δ13C excursion resulted from a brief but substantial increase in export production and carbon burial.
Laboratory simulation of the gyre in the Alboran Sea

A laboratory experiment is described which appears to exhibit flows which are similar to the flow-counterflow in the Strait of Gibraltar and, for certain values of the parameters involved, to the gyre and front in the Western Alboran Sea. The experiment is transient in nature and is made with two connecting basins on a rotating turntable. A sliding door is fitted into the channel connecting the two basins. Each basin is filled with water, the door is closed, and salt is added to one side so that the two waters have different densities. After the waters have spun up to rest in the rotating frame, the door is opened. A flow, driven by the density imbalance, is observed shortly thereafter, the lighter fluid rising up over the heavier fluid and pushing into the basin containing the heavy fluid. Likewise the heavy fluid pushes into the basin containing lighter fluid. For very rapid rotation these flows are violently unstable. For less rapid counterclockwise rotation both currents stay confined to a narrow jet which clings to the right-hand wall of the basins which they are entering. At some lower rate of rotation the jet cannot hold to a sufficiently curved wall, andmore » the jet separates from the wall: a gyre is observed between the jet and the wall. The gyre and the jet initially are both a Rossby radius in size, but gradually the gyre grows larger. Growth of the gyre seems to result from an accumulation of fluid from the jet as it returns to the wall. Scaling arguments and estimates of buoyancy, Coriolis, and wind forces are advanced in support of the concept that this laboratory-produced gyre and the gyre in the Alboran Sea share the same dynamics. « less
A theoretical and simulation study of the contact discontinuities based on a Vlasov simulation code

[1] Contact discontinuity (CD) is the simplest solution that can be obtained from the magnetohydrodynamics (MHD) Rankine-Hugoniot jump conditions. Due to the limitations of the previous kinetic simulation models, the stability of the CD has become a controversial issue in the past 10 years. The stability of the CD is reexamined analytically and numerically. Our theoretical analysis shows that the electron temperature profile and the ion temperature profile must be out of phase across the CD if the CD structure is to be stable in the electron time scale and with zero electron heat flux on either side of the CD. Both a newly developed fourth-order implicit electrostatic Vlasov simulation code and an electromagnetic finite-size particle code are used to examine the stability and the electrostatic nature of the CD structure. Our theoretical prediction is verified by both simulations. Our results of Vlasov simulation also indicate that a simulation with initial electron temperature profile and ion temperature profile varying in phase across the CD will undergo very transient changes in the electron time scale but will relax into a quasi-steady CD structure within a few ion plasma oscillation periods if a real ion-electron mass ratio is used in the simulation and if the boundary conditions allow nonzero heat flux to be presented at the boundaries of the simulation box. The simulation results of this study indicate that the Vlasov simulation is a powerful tool to study nonlinear phenomena with nonperiodic boundary conditions and with nonzero heat flux at the boundaries of the simulation box.
Impaired Cardiac Contractility in Mice Lacking Both the AE3 Cl /HCO Exchanger and the NKCC1 Na -2Cl Cotransporter EFFECTS ON Ca 2 (cid:2) HANDLING AND PROTEIN PHOSPHATASES *

To analyze the cardiac functions of AE3, we disrupted its gene ( Slc4a3 ) in mice. Cl (cid:1) /HCO 3 (cid:1) exchange coupled with Na (cid:2) -de-pendent acid extrusion can mediate pH-neutral Na (cid:2) uptake, potentially affecting Ca 2 (cid:2) handling via effects on Na (cid:2) /Ca 2 (cid:2) exchange. AE3 null mice appeared normal, however, and AE3 ablationhadnoeffectonischemia-reperfusioninjuryinisolated hearts or cardiac performance in vivo . The NKCC1 Na (cid:2) -K (cid:2) 2Cl (cid:1) cotransporter also mediates Na (cid:2) uptake, and loss of NKCC1alonedoesnotimpaircontractility.Tofurtherstressthe AE3-deficient myocardium, we combined the
On the Predictability of the Winter Euro-Atlantic Climate: Lagged Influence of Autumn Arctic Sea Ice

AbstractSatellite-derived sea ice concentration (SIC) and reanalyzed atmospheric data are used to explore the predictability of the winter Euro-Atlantic climate resulting from autumn SIC variability over the Barents–Kara Seas region (SIC/BK). The period of study is 1979/80–2012/13. Maximum covariance analyses show that the leading predictand is indistinguishable from the North Atlantic Oscillation (NAO). The leading covariability mode between September SIC/BK and winter North Atlantic–European sea level pressure (SLP) is not significant, indicating that no empirical prediction skill can be achieved. The leading covariability mode with either October or November SIC/BK is moderately significant (significance levels <10%), and both predictor fields yield a cross-validated NAO correlation of 0.3, suggesting some empirical prediction skill of the winter NAO index, with sea ice reduction in the Barents–Kara Seas being accompanied by a negative NAO phase in winter. However, only November SIC/BK provides signifi.
Proteomics of the astrocyte secretome reveals changes in their response to soluble oligomeric Aß

Astrocytes associate with amyloid plaques in Alzheimer’s disease (AD). Astrocytes react to changes in the brain environment, including to increasing concentrations of amyloid-ß (Aß). However, the precise response of astrocytes to soluble small Aß oligomers at concentrations similar to those present in the human brain has not been addressed. In this study, we exposed astrocytes to neuronal media containing soluble human Aß oligomers and used proteomics to investigate changes in the astrocyte secretome. Our data shows dysregulated secretion of astrocytic proteins involved in the extracellular matrix and cytoskeletal organization and increase secretion of proteins involved in oxidative stress responses and those with chaperone activity. Several of these proteins have been identified in previous transcriptomic and proteomic studies using brain tissue from human AD and cerebrospinal fluid (CSF). Our work highlights the relevance of studying astrocyte secretion to understand the brain response to AD pathology and the potential use of these proteins as biomarkers for the disease.
Sinkhole “swarms” along the Dead Sea coast: Reflection of disturbance of lake and adjacent groundwater systems

More than a thousand sinkholes have developed along the western coast of the Dead Sea since the early 1980s, more than 75% of them since 1997, all occurring within a narrow strip 60 km long and <1 km wide. This highly dynamic sinkhole development has accelerated in recent years to a rate of ∼150–200 sinkholes per year. The sinkholes cluster mostly over specific sites up to 1000 m long and 200 m wide, which spread parallel to the general direction of the fault system associated with the Dead Sea Transform. Research employing borehole and geophysical tools reveals that the sinkhole formation results from the dissolution of an ∼10,000-yr-old salt layer buried at a depth of 20–70 m below the surface. The salt dissolution by groundwater is evidenced by direct observations in test boreholes; these observations include large cavities within the salt layer and groundwater within the confined subaquifer beneath the salt layer that is undersaturated with respect to halite. Moreover, the groundwater brine within the salt layer exhibits geochemical evidence for actual salt dissolution (Na/Cl = 0.5–0.6 compared to Na/Cl = 0.25 in the Dead Sea brine). The groundwater heads below the salt layer have the potential for upward cross-layer flow, and the water is actually invading the salt layer, apparently along cracks and active faults. The abrupt appearance of the sinkholes, and their accelerated expansion thereafter, reflects a change in the groundwater regime around the shrinking lake and the extreme solubility of halite in water. The eastward retreat of the shoreline and the declining sea level cause an eastward migration of the fresh–saline water interface. As a result the salt layer, which originally was saturated with Dead Sea water over its entire spread, is gradually being invaded by fresh groundwater at its western boundary, which mixes and displaces the original Dead Sea brine. Accordingly, the location of the western boundary of the salt layer, which dates back to the shrinkage of the former Lake Lisan and its transition to the current Dead Sea, constrains the sinkhole distribution to a narrow strip along the Dead Sea coast. The entire phenomenon can be described as a hydrological chain reaction; it starts by intensive extraction of fresh water upstream of the Dead Sea, continues with the eastward retreat of the lake shoreline, which in turn modifies the groundwater regime, finally triggering the formation of sinkholes.
Article in Press Information and Computation Xxx (2006) Xxx–xxx Quasi-optimal Energy-efficient Leader Election Algorithms in Radio Networks 2 Article in Press Disk / 9/11/2006 (ce) / Panneer (te) Dtd 5.0.1 Sps

Radio networks (RN) are distributed systems (ad hoc networks) consisting in n 2 radio stations. Assum-8 ing the number n unknown, two distinct models of RN without collision detection (no-CD) are addressed: 9 the model with weak no-CD RN and the one with strong no-CD RN. We design and analyze two distributed 10 leader election protocols, each one running in each of the above two (no-CD RN) models, respectively. Both 11 randomized protocols are shown to elect a leader within O(log (n)) expected time, with no station being awake 12 for more than O(log log (n)) time slots (such algorithms are said to be energy-efficient). Therefore, a new class 13 of efficient algorithms is set up that match the (log (n)) time lower-bound established by Kushilevitz and 14 Mansour [E. Kushilevitz, Y. Mansour, An (D log (N/D)) lower-bound for broadcast in radio networks, 2 C. Lavault et al. / Information and Computation xxx (2006) xxx–xxx
Seasonal current simulations for the western continental margin of Vancouver Island

Two three-dimensional finite element models, one diagnostic and one semiprognostic, are used to simulate summer and winter currents for the western continental margin of Vancouver Island, British Columbia. The calculations are forced (or nudged) with seasonal winds, climatological density fields, and elevation-specified boundary conditions that have been adjusted via inversion to more accurately represent the California Undercurrent and estuarine flow in Juan de Puca Strait. Tides are included in the simulations in order to correctly represent turbulent mixing, bottom friction, and the contribution of tidal rectification. The seasonal model currents are shown to compare favorably with multiyear, low-pass filtered current meter observations and to capture strong shears both vertically in Juan de Fuca Strait and horizontally and vertically across the continental shelf and slope. The tidal currents are more accurate than those computed with a previous three-dimensional barotropic model.
The use of three geophysical methods for 3D images of total root volume of soil in urban environments

How does the tree root system develop in the subsoil? This question is important to the development and urban planning disciplines, especially when the trees occur near building foundations and underground utilities. This interest is based on the potential for buildings to suffer subsidence or structural damage from nearby trees. The inspection of both the extension of the tree roots and the degree of decay in wood are still undertaken using classical single-point and destructive methods. However, as pointed out by several authors, geophysical methods provide an alternative method of studying root architecture in a non-invasive fashion. In this paper, three geophysical methods were applied to produce 3D images of total root volume in the soil in an urban environment. The three geophysical methods used were ground-penetrating radar, electrical-resistivity tomography, and seismic refraction tomography. Each of the geophysical methods alone is able to isolate root system but cannot resolve the ring structures.
INFLUÊNCIA DO SÍTIO NO DESENVOLVIMENTO DO Pinus taeda AOS 22 ANOS: 1. CARACTERÍSTICAS FÍSICO-HÍDRICAS E QUÍMICAS DO SOLO

In order to evaluate the influence of site quality on pine tree growth, eight different sites were selected in a commercial Pinus taeda plantation belonging to Klabin, in Telemaco Borba region, Parana State. Trees were 22 years old and sites were selected by soil type (Latosol and Cambisol), by soil texture (clayey and sandy) and by original vegetation (forest and grass). To characterize the sites, measurements of total height and DBH were taken from at least 50 trees at each site and soil samples were collected at three depths. Three average trees were selected from each site and DBH and total, sawing and cellulose heights were measured. The most important factor influencing tree growth, considering DBH increment, was the original vegetation phase. Original forest sites were the most productive of all. Cambissolo with loam texture and forest as original vegetation was the most productive site and the least productive site was a Cambissolo with loam texture and grass as original vegetation. The most productive site presented higher P and K contents, higher pH, higher base saturation and lower Al saturation percentage. This site presented lower total and macro porosities, higher bulk density and higher amount of available soil water, which was highly correlated to the growth variables
Key role for cyclooxygenase-2 in PGE 2 and PGF 2 (cid:97) receptor regulation and cerebral blood f low of the newborn

Sylvain Chemtob. Key role for cyclooxygenase-2 in PGE 2 and PGF 2 (cid:97) receptor regulation and cerebral blood ﬂow of the newborn. Am. J. Physiol. 273 ( Regulatory Integrative Comp. Physiol. 42): R1283–R1290, 1997. —Ibuprofen, a cyclooxygenase (COX) inhibitor nonselective for either COX-1 or COX-2 isoform, upregulates cerebrovascular prostaglandin E 2 (PGE 2 ) and PGF 2 (cid:97) receptors in newborn pigs. COX-2 was shown to be the predominant form of COX and the main catalyst of prostaglandin synthesis in the newborn brain. We proceeded to establish direct evidence that COX-2-generated prostaglandins govern PGE 2 and PGF 2 (cid:97) receptor density and function in the cerebral vasculature of the newborn. Hence, we determined PGE 2 and PGF 2 (cid:97) receptor density and functions in brain vasculature by using newborn pigs treated with saline, ibuprofen, COX-1 inhibitor (valerylsalicylate), or COX-2 inhibitors (DUP-697 and NS-398). Newborn brain PGE 2 and PGF 2 (cid:97) concentrations were signiﬁcantly reduced by ibupro- fen, DUP-697, and NS-398 but not by valerylsalicylate. In newborn pigs treated with DUP-697, NS-398, and ibuprofen, PGE 2 and PGF 2 (cid:97) receptor densities in brain microvessels were increased to adult levels; there was also a signiﬁcant increase in inositol 1,4,5-trisphosphate (IP 3 ) production and cerebral vasoconstrictor effects of 17-phenyl trinor PGE 2 (EP 1 receptor agonist), M&B-28767 (EP 3 receptor agonist), PGF 2 (cid:97) , and fenprostalene (PGF 2 (cid:97) analog). Treatment with ibuprofen or DUP-697 also increased the upper blood pressure limit of cerebral cortex and periventricular blood ﬂow autoregulation from 85 to (cid:36) 125 mmHg (uppermost blood pressure studied). However, valerylsalicylate treatment did not affect cerebrovascular PGE 2 and PGF 2 (cid:97) receptors, IP 3 production, or vasocon- strictor effects in newborn animals. These in vivo and in vitro observations indicate that COX-2 is mainly responsible for the regulation of PGE 2 and PGF 2 (cid:97) receptors and their func- tions in the newborn cerebral vasculature.
North Atlantic Deep Water cools the southern hemisphere

A standard explanation for coupling climate variations in the northern and southern hemispheres involves fluctuations in North Atlantic Deep Water (NADW) production. However, I suggest that the “NADW-Antarctic” connection may work opposite to that conjectured by many investigators; that is, when NADW production rates are high, southern hemisphere temperatures decrease rather than increase. The revised interpretation is consistent with observations and ocean modeling studies which demonstrate that, although upwelling of relatively warm NADW water around Antarctica promotes sea ice meltback, a second and more important negative feedback is also operating. In order to conserve volume, southward export of NADW across the equator is accompanied by import of an equivalent volume of considerably warmer water from shallower oceanic layers in the South Atlantic. The southern hemisphere loses heat as a result of this exchange. The hemispherically averaged net heat loss may be as high as 4 W/m², an amount comparable to a CO2 doubling. It is suggested that this more comprehensive view of the role of NADW may explain both decadal-scale variations in South Atlantic sea surface temperatures in this century and two significant problems in Pleistocene climatology: why southern hemisphere temperatures decreased before CO2 levels decreased at the end of the last interglacial and why southern hemisphere temperature changes precede changes in northern hemisphere ice volume. It is shown that when NADW production was reinitiated during the last interglacial (120,000 B.P.), high-latitude southern hemisphere temperatures decreased. The estimated magnitude of altered southern hemisphere heat export is comparable to the ice-age CO2 signal and may be able to account for the observed cooling even when CO2 levels were high. When cast into a frequency domain framework, this interpretation may also help explain why southern hemisphere temperatures lead global ice volume changes.
Multi-year monitoring of rice crop phenology through time series analysis of MODIS images

Precise phenological calendars, for each cultivated species and variety, are necessary both to highlight anomalous agronomic situations and to feed crop models. This study, conducted in the Italian rice area, focuses on the evaluation of the contribution of remote sensing satellite data to providing phenological information on rice cropping systems. A time series of 5 years (2001–2005) of the Moderate Resolution Imaging Spectrometer (MODIS) Normalized Difference Vegetation Index (NDVI) 16-day composites was analysed with the TIMESAT program in order to automatically retrieve key phenological information such as the start of season (emergence), peak (heading) and end of season (maturity). The procedure involved two steps: (1) interpolation and smoothing of MODIS NDVI temporal profile and (2) the analysis of a temporal signal for the extraction of the phenological metrics. The remote sensing estimates were evaluated using information regarding cultivated variety, sowing dates, management and production directly acquired from rice farmers. A good correlation (R 2 = 0.92, n = 24) has been observed between estimates derived from satellites and estimates produced with the traditional Growing Degree Days (GDD) method based on thermal unit accumulation. Improved estimates of the maturity stage were obtained using a procedure that integrates satellite and GDD methods; however its application requires spatially distributed information on the cultivated varieties. Satellite derived maps of the retrieved phenological parameters showed an intra-seasonal pattern related to different cultivated varieties. Inter-seasonal analysis allowed the anomalous behaviour of the year 2003 to be highlighted, characterized by rapid growth at the beginning of the spring and an early senescence. The results confirm the potential of remotely sensed data for the monitoring of crop status and for the forcing of crop models in a spatially distributed way.
Necessary Conditions for Tropical Cyclone Rapid Intensification as Derived from 11 Years of TRMM Data

AbstractRainfall and convective properties of tropical cyclones (TCs) are statistically quantified for different TC intensity change categories by using Tropical Rainfall Measuring Mission (TRMM) data from December 1997 to December 2008. Four 24-h future intensity change categories are defined: rapidly intensifying (RI), slowly intensifying, neutral, and weakening. It is found that RI storms always have a larger raining area and total volumetric rain in the inner core. The maximum convective intensity in the inner core is not necessarily more intense prior to undergoing an RI episode than a slowly intensifying, neutral, or weakening episode. Instead, a minimum threshold of raining area, total volumetric rain, and convective intensity in the inner core is determined from the RI cases examined in this study. The following necessary conditions for RI are found in the inner core: total raining area > 3000 km2, total volumetric rain > 5000 mm h−1 km2, maximum near-surface radar reflectivity > 40 dBZ, maximum 2.
Radio occultation measurements of turbulence in the Venus atmosphere by Pioneer Venus

As in the cases of Mariner 5 and 10 and Venera 9, the Pioneer Venus radio occultation measurements of Venus show an upper region of turbulence located in the vicinity of 60 km. Estimates of the deduced intensity of turbulence are consistent with the upper bound obtained earlier from the complementary Pioneer Venus probe measurements. Comparison with the Pioneer Venus in situ temperature measurements of 1 km scale size also shows very good agreement. It is clear that for scale sizes smaller than the Fresnel size (∼1 km), the refractive index irregularities are represented by a continuum of scale sizes having a spatial wave number spectrum that is power law and close to Kolmogorov. These irregularities are elongated in the horizontal direction (axial ratios are large, ≳10). The fact that the upper region of turbulence coincides with a region of high stability marked by one or more peaks in the stability profile suggests that the turbulence is associated with trapped gravity waves. The amplitude scintillations appear to increase poleward of about 70° which is interpreted as an increase in turbulence level with latitude.