Outflow Dynamics Research Articles

RESOLVING GAS FLOWS IN THE ULTRALUMINOUS STARBURST IRAS 23365+3604 WITH KECK LGSAO/OSIRIS*

ABSTRACT Keck OSIRIS/LGSAO observations of the ultraluminous galaxy IRAS 23365+3604 resolve a circumnuclear bar (or irregular disk) of semimajor axis 0.″42 (520 pc) in Paα emission. The line-of-sight velocity of the ionized gas increases from the northeast toward the southwest; this gradient is perpendicular to the photometric major axis of the infrared emission. Two pairs of bends in the zero-velocity line are detected. The inner bend provides evidence for gas inflow onto the circumnuclear disk/bar structure. We interpret the gas kinematics on kiloparsec scales in relation to the molecular gas disk and multiphase outflow discovered previously. In particular, the fast component of the ouflow (detected previously in line wings) is not detected, adding support to the conjecture that the fast wind originates well beyond the nucleus. These data directly show the dynamics of gas inflow and outflow in the central kiloparsec of a late-stage, gas-rich merger and demonstrate the potential of integral field spectroscopy to improve our understanding of the role of gas flows during the growth phase of bulges and supermassive black holes.

The study of the process of evolution of the jet under outflow of water from the supercritical state through a thin nozzle

The dynamics of the water outflow from the initial supercritical state through a thin nozzle is studied. To describe the initial stage of non-stationary process outflow the system of differential equations of conservation of mass, momentum and energy in a two-dimensional cylindrical coordinates with axial symmetry is used. The spatial distribution of pressure and velocity of jet formation was received. It was established that a supersonic regime of outflow at supercritical temperature of 650 K is formed, which have a qualitative agreement for the velocity compared with the Bernoulli analytical solution and the experimental data.

Rear-Flank Outflow Dynamics and Thermodynamics in the 10 June 2010 Last Chance, Colorado, Supercell

On 10 June 2010, the second Verification of the Origins of Tornadoes Experiment (VORTEX2) armada observed a supercell thunderstorm near Last Chance, Colorado. Tempest unmanned aircraft system (UAS) data collected in the rear-flank outflow revealed what appeared to be an elevated outflow head, turbulent wake, and a cold rear-flank internal surge (RFIS). Surface thermodynamic and kinematic data collected by the StickNet and mobile mesonet indicated that the outflow wake may have extended to or very near the surface, perhaps modifying or outright replacing the leading edge of the outflow at times. Single-Doppler data collected by the NOAA X-Pol Mobile Polarimetric Doppler Radar (NOXP) were supportive of the possibility of a downdraft in the outflow wake associated with low-level divergence. A conceptual model of the hypothesized rear-flank outflow structure in the nontornadic phase of the Last Chance supercell is presented. The observed turbulent wake is consistent with mixing associated with the release of Kelvin–Helmholtz instability rearward of a density current head. Observations also support the hypothesis that the RFIS would not have existed without the turbulent wake.

Differential left ventricular outflow tract remodeling and dynamics in aortic stenosis.

Left ventricular outflow tract (LVOT) geometry is variable and often elliptical, which can affect aortic valve area calculation in patients with aortic stenosis (AS). Specific differences in LVOT geometry and dynamics between patients with AS and normal control subjects have not been described. The aim of this study was to test the hypothesis that differences in LVOT geometry in patients with AS might relate to variable LVOT remodeling and stiffness relative to normal control subjects. In 54 patients with severe AS and 33 control subjects without AS, LVOT geometry, dynamics, remodeling, and stiffness were assessed by three-dimensional transesophageal echocardiography. LVOT stiffness was measured by calculating the distensibility coefficient, defined as the percentage change in LVOT area relative to change in left ventricular pressure. LVOT remodeling was assessed by measuring the posterior LVOT wall thickness. Multivariate linear regression analysis was used to determine independent associations with peak systolic LVOT ellipticity. LVOT area by three-dimensional transesophageal echocardiographic planimetry was compared with areas obtained assuming circular or elliptical geometry. At end-diastole, LVOT geometry was similar between patients with AS and normal control subjects. In patients with AS, however, the percentage change in cross-sectional area (7.5% vs 14.7%, P<.001) from end-diastole to peak systole was lower compared with normal control subjects, while peak systolic ellipticity index was higher in patients with AS (1.18 vs 1.08, P<.001). Compared with control subjects, patients with AS had lower distensibility coefficients (4.7±1.9 × 10(4) vs 12.5±5.3×10(4) mm Hg(-1), P<.001) and higher posterior LVOT wall thickness (3.5±0.8 vs 2.3±0.5mm, P<.001). In multivariate analysis, posterior LVOT wall thickness and distensibility coefficient were independently associated with peak systolic LVOT ellipticity index. LVOT area underestimation by transthoracic echocardiography was higher in patients with AS when assuming circular geometry (20% vs 12%, P=.001). The LVOT is less distensible and undergoes remodeling in severe AS. These changes lead to greater peak systolic ellipticity and greater LVOT cross-sectional area underestimation relative to normal control subjects. These findings have important implications for the assessment of AS severity.

A distance-limited sample of massive molecular outflows

We have observed 99 mid-infrared-bright, massive young stellar objects and compact HII regions drawn from the Red MSX source (RMS) survey in the J=3$-$2 transition of $^{12}$CO and $^{13}$CO, using the James Clerk Maxwell Telescope. 89 targets are within 6 kpc of the Sun, covering a representative range of luminosities and core masses. These constitute a relatively unbiased sample of bipolar molecular outflows associated with massive star formation. Of these, 59, 17 and 13 sources (66, 19 and 15 percent) are found to have outflows, show some evidence of outflow, and have no evidence of outflow, respectively. The time-dependent parameters of the high-velocity molecular flows are calculated using a spatially variable dynamic timescale. The canonical correlations between the outflow parameters and source luminosity are recovered and shown to scale with those of low-mass sources. For coeval star formation we find the scaling is consistent with all the protostars in an embedded cluster providing the outflow force, with massive stars up to $\sim$30 M$_{\odot}$ generating outflows. Taken at face value, the results support the model of a scaled-up version of the accretion-related outflow-generation mechanism associated with discs and jets in low-mass objects with time-averaged accretion rates of $\sim$10$^{-3}$ M$_{\odot}$ yr$^{-1}$ onto the cores. However, we also suggest an alternative model, in which the molecular outflow dynamics are dominated by the entrained mass and are unrelated to the details of the acceleration mechanism. We find no evidence that outflows contribute significantly to the turbulent kinetic energy of the surrounding dense cores.

The two‐way relationship between ionospheric outflow and the ring current

AbstractIt is now well established that the ionosphere, because it acts as a significant source of plasma, plays a critical role in ring current dynamics. However, because the ring current deposits energy into the ionosphere, the inverse may also be true: the ring current can play a critical role in the dynamics of ionospheric outflow. This study uses a set of coupled, first‐principles‐based numerical models to test the dependence of ionospheric outflow on ring current‐driven region 2 field‐aligned currents (FACs). A moderate magnetospheric storm event is modeled with the Space Weather Modeling Framework using a global MHD code (Block Adaptive Tree Solar wind Roe‐type Upwind Scheme, BATS‐R‐US), a polar wind model (Polar Wind Outflow Model), and a bounce‐averaged kinetic ring current model (ring current atmosphere interaction model with self‐consistent magnetic field, RAM‐SCB). Initially, each code is two‐way coupled to all others except for RAM‐SCB, which receives inputs from the other models but is not allowed to feed back pressure into the MHD model. The simulation is repeated with pressure coupling activated, which drives strong pressure gradients and region 2 FACs in BATS‐R‐US. It is found that the region 2 FACs increase heavy ion outflow by up to 6 times over the noncoupled results. The additional outflow further energizes the ring current, establishing an ionosphere‐magnetosphere mass feedback loop. This study further demonstrates that ionospheric outflow is not merely a plasma source for the magnetosphere but an integral part in the nonlinear ionosphere‐magnetosphere‐ring current system.

Aqueous Humor Outflow: Dynamics and Disease

This review summarizes the goals and outcomes of the eighth annual ARVO/Pfizer Ophthalmic Research Institute conference that was held on May 4th and 5th, 2012, at the Embassy Suites Fort Lauderdale, Fort Lauderdale, Florida. This conference series has been funded by the ARVO Foundation for Eye Research with the help of a generous grant from Pfizer Ophthalmics. Funding from the ARVO/Pfizer Ophthalmics Research Institute has allowed a series of “think tanks” for the leading experts on various subspecialties of ophthalmology research. These meetings have helped to define various challenges and potential solutions to issues relevant to the field of ophthalmology. In 2012, the emphasis of the conference was on the physiological role of the conventional outflow pathway in aqueous humor dynamics in normal and glaucomatous eyes. In particular, clinical observations associated with aqueous humor outflow in health and disease, animal models in the understanding of aqueous outflow, role of mechanosensing in aqueous humor fluid flow, and new paradigms in cell and extracellular matrix crosstalk within the conventional outflow pathway were discussed. The primary goal of the conference was to bring together a diverse group of experts who are pioneers in conventional outflow biology and related nonocular areas of research with the hope of utilizing the group's knowledge and experience to evaluate the current understanding of aqueous outflow regulation and problems thereof. The invited group consisted of 29 investigators directly involved in conventional outflow research. Also present were three invited outside experts in cellular mechanics and cytoskeleton structures (Jeffrey Fredberg, PhD, Harvard School of Public Health, Boston, MA, USA), molecular mechanisms of cell adhesion and mechanosensing (Benjamin Geiger, PhD, Weizmann Institute of Science, Rehovot, Israel), and murine genetics (Richard Libby, PhD, University of Rochester Medical Center, Rochester, NY, USA). In addition, the conference was attended by 27 observers who participated in discussion of key topics at the end of each presentation. Together, the group was tasked with reviewing the current scientific dogma regarding aqueous outflow diseases and identifying the most pressing research questions and needs in the current funding environment. Above all, the group was asked to think “outside the box” to develop future research directions. The conference generated a list of highly relevant but currently unanswered questions with the hope that solutions to these issues would improve understanding of the role of the conventional outflow pathway in normal and glaucoma eyes. The meeting was organized into four sessions: (a) clinical insights into conventional outflow dysfunction, (b) the use of mice as model systems for conventional outflow, (c) mechanosensing within the conventional outflow pathway, and (d) the role of the extracellular matrix and signaling in conventional outflow dynamics. Speakers presented their thoughts on the preselected topics and provided key research goals that have been addressed or need to be addressed in the near future. The sessions were followed by discussion aimed at summarizing and interpreting the current knowledge as well as identifying unique research questions that were as yet unanswered. Anatomy and Physiology of the Conventional Aqueous Humor Outflow Pathway The conventional outflow pathway is mainly a pressure-driven system. Under homeostatic conditions, this pathway regulates the drainage of aqueous humor from the anterior chamber of the eye, thereby maintaining a constant intraocular pressure (IOP).1 Relevant tissues of the anterior segment that are anatomically involved in IOP control include the ciliary muscles, trabecular meshwork (TM), Schlemm's canal (SC), collector channels, and aqueous veins. The ciliary muscle is composed of smooth muscle fibers that have a true elastic net of tendons that anchor into the choroid posteriorly and the scleral spur, TM, and inner wall of SC anteriorly.2,3 It is widely accepted that contraction of the ciliary muscle causes expansion of the TM and opening of SC, which subsequently increases the conductivity of aqueous humor (AH) through the TM. All these, along with reports of nerve innervation in the TM, indicate that the TM is a self-regulating tissue with both afferent and efferent nervous components responsible for controlling its functions.2,4

Effects of heating temperature and duration by gold nanorod mediated plasmonic photothermal therapy on copolymer accumulation in tumor tissue.

Previously, water-soluble N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers have been used with gold nanorod (GNR) mediated plasmonic photothermal therapy (PPTT) to induce hyperthermia (43 °C for 10 min) and have been shown to improve delivery of hydrophobic drugs to treat cancer. However, it was unknown how altering the heating parameters (temperature and duration) of PPTT would affect HPMA copolymer accumulation and retention. This study aimed to investigate how changes in heating parameters, or thermal dose, would change polymer accumulation profiles with PPTT. It was observed that temperatures of either 40, 43, 46, or 49 °C at durations of 10 or 30 min had significant effects on HPMA copolymer accumulation. Mild temperatures led to transient enhancement in accumulation, but more severe temperatures led to tissue and vascular damage, creating slowed dynamics of inflow and outflow of the polymers from the tumor tissue.

The SiO outflow from IRAS 17233-3606 at high resolution

Context: Jets and outflows are key ingredients in the formation of stars across the mass spectrum. In clustered regions, understanding powering sources and outflow components poses a significant problem. Aims: To understand the dynamics in the outflow(s) from a cluster in the process of forming massive stars. Methods: We use new VLA observations of the molecular gas (SiO, CS, OCS and \molec) in the massive star forming region IRAS 17233-3606 which contains a number of HII regions. We compare these observations to previously published molecular data for this source in order to get a holistic view of the outflow dynamics. Results:We find that the dynamics of the various species can be explained by a single large scale ($\sim 0.15$ pc) outflow when compared to the sizes of the HII regions, with the different morphologies of the blue and red outflow components explained with respect to the morphology of the surrounding envelope. We further find that the direction of the velocity gradients seen in OCS and \molec are suggestive of a combination of rotation and outflow motions in the warm gas surrounding the HII regions near the base of the large scale outflow. Conclusions: Our results show that the massive protostars forming within this region appear to be contributing to a single outflow on large scales. This single large scale outflow is traced by a number of different species as the outflow interacts with its surroundings. On the small scales, there appear to be multiple mechanisms contributing to the dynamics which could be a combination of either a small scale outflow or rotation with the dynamics of the large scale outflow.

Santorinicele: secretin-enhanced magnetic resonance cholangiopancreatography findings before and after minor papilla sphincterotomy

To evaluate secretin-enhanced MRCP (S-MRCP) findings of patients with pancreas divisum and Santorinicele, before and after minor papilla sphincterotomy. S-MRCP examinations of 519 patients with suspected pancreatic disease were included. Size of the main pancreatic duct, presence and calibre of Santorinicele were evaluated. Duodenal filling was assessed on dynamic images. After sphincterotomy the same parameters and the clinical findings were re-evaluated. Pancreas divisum was depicted in 55/519 patients (11%) by MRCP and an additional 26/519 by S-MRCP (total 81/519, 16%). Santorinicele was detected in 7/81 patients (8.6%) with pancreas divisum by MRCP and an additional 20/81 by S-MRCP (total 27/81, 33%). Dorsal duct in patients with Santorinicele was significantly larger in the head compared with patients with only pancreas divisum (p < 0.01), in basal conditions (average 2.4 versus 1.9mm) and after secretin administration (average 3.0 versus 2.4mm). Duodenal filling was impaired in 11/27 patients (41%) with Santorinicele. After sphincterotomy significant reduction in size of Santorinicele (-33%) and dorsal duct (-17%), increase of pancreatic juice and symptoms improvement were observed. Secretin administration increases the accuracy of MRCP in detecting Santorinicele and demonstrates the impaired duodenal filling. S-MRCP is useful to assess results of sphincterotomy. • Secretin-enhanced MRCP gives anatomical and functional information on pancreatic outflow dynamics. • Santorinicele is a cystic dilatation of the termination of the Santorini duct. • S-MRCP images are the most useful to recognize the presence of Santorinicele. • Minor papilla sphincterotomy during ERCP is indicated in patients with Santorinicele.

Physics of Gamma-Ray Bursts Prompt Emission

In recent years, our understanding of gamma-ray bursts (GRB) prompt emission has been revolutionized, due to a combination of new instruments, new analysis methods, and novel ideas. In this review, I describe the most recent observational results and current theoretical interpretation. Observationally, a major development is the rise of time resolved spectral analysis. These led to (I) identification of a distinguished high energy component, with GeV photons often seen at a delay and (II) firm evidence for the existence of a photospheric (thermal) component in a large number of bursts. These results triggered many theoretical efforts aimed at understanding the physical conditions in the inner jet regions. I highlight some areas of active theoretical research. These include (I) understanding the role played by magnetic fields in shaping the dynamics of GRB outflow and spectra; (II) understanding the microphysics of kinetic and magnetic energy transfer, namely, accelerating particle to high energies in both shock waves and magnetic reconnection layers; (III) understanding how subphotospheric energy dissipation broadens the “Planck” spectrum; and (IV) geometrical light aberration effects. I highlight some of these efforts and point towards gaps that still exist in our knowledge as well as promising directions for the future.

Cerebral venous outflow and cerebrospinal fluid dynamics

In this review, the impact of restricted cerebral venous outflow on the biomechanics of the intracranial fluid system is investigated. The cerebral venous drainage system is often viewed simply as a series of collecting vessels channeling blood back to the heart. However there is growing evidence that it plays an important role in regulating the intracranial fluid system. In particular, there appears to be a link between increased cerebrospinal fluid (CSF) pulsatility in the Aqueduct of Sylvius and constricted venous outflow. Constricted venous outflow also appears to inhibit absorption of CSF into the superior sagittal sinus. The compliance of the cortical bridging veins appears to be critical to the behaviour of the intracranial fluid system, with abnormalities at this location implicated in normal pressure hydrocephalus. The compliance associated with these vessels appears to be functional in nature and dependent on the free egress of blood out of the cranium via the extracranial venous drainage pathways. Because constricted venous outflow appears to be linked with increased aqueductal CSF pulsatility, it suggests that inhibited venous blood outflow may be altering the compliance of the cortical bridging veins.

Instantaneous monitoring of heart beat dynamics during anesthesia and sedation

AbstractAnesthesia-induced altered arousal depends on drugs having their effect in specific brain regions. These effects are also reflected in autonomic nervous system (ANS) outflow dynamics. To this extent, instantaneous monitoring of ANS outflow, based on neurophysiological and computational modeling, may provide a more accurate assessment of the action of anesthetic agents on the cardiovascular system. This will aid anesthesia care providers in maintaining homeostatic equilibrium and help to minimize drug administration while maintaining antinociceptive effects. In previous studies, we established a point process paradigm for analyzing heartbeat dynamics and have successfully applied these methods to a wide range of cardiovascular data and protocols. We recently devised a novel instantaneous nonlinear assessment of ANS outflow, also suitable and effective for real-time monitoring of the fast hemodynamic and autonomic effects during induction and emergence from anesthesia. Our goal is to demonstrate that our framework is suitable for instantaneous monitoring of the ANS response during administration of a broad range of anesthetic drugs. Specifically, we compare the hemodynamic and autonomic effects in study participants undergoing propofol (PROP) and dexmedetomidine (DMED) administration. Our methods provide an instantaneous characterization of autonomic state at different stages of sedation and anesthesia by tracking autonomic dynamics at very high time-resolution. Our results suggest that refined methods for analyzing linear and nonlinear heartbeat dynamics during administration of specific anesthetic drugs are able to overcome nonstationary limitations as well as reducing inter-subject variability, thus providing a potential real-time monitoring approach for patients receiving anesthesia.

Modeling the effect of soil structure on water flow and isoproturon dynamics in an agricultural field receiving repeated urban waste compost application

Transport processes in soils are strongly affected by heterogeneity of soil hydraulic properties. Tillage practices and compost amendments can modify soil structure and create heterogeneity at the local scale within agricultural fields. The long-term field experiment QualiAgro (INRA–Veolia partnership 1998–2013) explores the impact of heterogeneity in soil structure created by tillage practices and compost application on transport processes. A modeling study was performed to evaluate how the presence of heterogeneity due to soil tillage and compost application affects water flow and pesticide dynamics in soil during a long-term period. The study was done on a plot receiving a co-compost of green wastes and sewage sludge (SGW) applied once every 2years since 1998. The plot was cultivated with a biannual rotation of winter wheat–maize (except 1year of barley) and a four-furrow moldboard plow was used for tillage. In each plot, wick lysimeter outflow and TDR probe data were collected at different depths from 2004, while tensiometer measurements were also conducted during 2007/2008. Isoproturon concentration was measured in lysimeter outflow since 2004. Detailed profile description was used to locate different soil structures in the profile, which was then implemented in the HYDRUS-2D model. Four zones were identified in the plowed layer: compacted clods with no visible macropores (Δ), non-compacted soil with visible macroporosity (Γ), interfurrows created by moldboard plowing containing crop residues and applied compost (IF), and the plow pan (PP) created by plowing repeatedly to the same depth. Isoproturon retention and degradation parameters were estimated from laboratory batch sorption and incubation experiments, respectively, for each structure independently. Water retention parameters were estimated from pressure plate laboratory measurements and hydraulic conductivity parameters were obtained from field tension infiltrometer experiments. Soil hydraulic properties were optimized on one calibration year (2007/08) using pressure head, water content and lysimeter outflow data, and then tested on the whole 2004/2010 period. Lysimeter outflow and water content dynamics in the soil profile were correctly described for the whole period (model efficiency coefficient: 0.99) after some correction of LAI estimates for wheat (2005/06) and barley (2006/07). Using laboratory-measured degradation rates and assuming degradation only in the liquid phase caused large overestimation of simulated isoproturon losses in lysimeter outflow. A proper order of magnitude of isoproturon losses was obtained after considering that degradation occurred in solid (sorbed) phase at a rate 75% of that in liquid phase. Isoproturon concentrations were found to be highly sensitive to degradation rates. Neither the laboratory-measured isoproturon fate parameters nor the independently-derived soil hydraulic parameters could describe the actual multiannual field dynamics of water and isoproturon without calibration. However, once calibrated on a limited period of time (9months), HYDRUS-2D was able to simulate the whole 6-year time series with good accuracy.

Exit probability in inflow dynamics: nonuniversality induced by range, asymmetry, and fluctuation.

Probing deeper into the existing issues regarding the exit probability (EP) in one-dimensional dynamical models, we consider several models where the states are represented by Ising spins and the information flows inwards. At zero temperature, these systems evolve to either of two absorbing states. The EP, E(x), which is the probability that the system ends up with all up spins starting with x fraction of up spins, is found to have the general form E(x)=xα/xα+(1-x)α. The EP exponent α strongly depends on r, the range of interaction, the symmetry of the model, and the induced fluctuation. Even in a nearest-neighbor model, a nonlinear form of the EP can be obtained by controlling the fluctuations, and for the same range, different models give different results for α. Nonuniversal behavior of the EP is thus clearly established and the results are compared to those of existing studies in models with outflow dynamics to distinguish the two dynamical scenarios.

Risk of Death and Need for Transplantation in Chronic Pulmonary Hypertension

BackgroundEcho-Doppler parameters that exemplify right ventricular (RV) outflow dynamics and measures of annular tissue Doppler imaging to assess left ventricular (LV) and RV diastolic function, known to be affected in chronic pulmonary hypertension (cPH), have never been studied to determine if they could be predictive of mortality or need for transplantation 1-year after follow-up. MethodsNumerous echo-Doppler parameters of RV and LV performance were recorded from 120 patients. This patient population was divided into 3 groups. Group I had no PH, group II had cPH but no documented death or need for either lung or heart transplantation, at 1-year follow-up after their initial echocardiogram whereas group III had cPH and patients had either died or required heart and/or lung transplantation during the same time period. ResultsAnalysis of variance was first used to identify which echo-Doppler variables were significant among the studied groups. A logistic regression analysis was then performed to identify predictive variables of the occurrence death and need for transplantation. Finally, a multiple regression analysis was used between groups II and III to identify which echo-Doppler variables were most useful in identifying severe cPH patients at risk of the prespecified events. ConclusionsEven though older patients with worse RV fractional area change might be considered at risk of worse prognosis in patients with severe cPH, only a low mitral annular early diastolic velocity was useful in identifying which of those individuals were at highest risk of death or in need of transplantation.

The Dynamics of Aqueous Humor Outflow—A Major Review

Aqueous humor outflow occurs through the conventional and unconventional pathway. With aging, the latter becomes less active so that the conventional pathway remains the primary mechanism of aqueous humor outflow. An abnormality of this pathway contributes significantly to disordered aqueous humor dynamics and consequent rise in intraocular pressure seen in primary open angle glaucoma and ocular hypertension. Recently, the ocular lymphatics have been implicated in aqueous humor outflow. Additionally, the trabecular meshwork is now understood to be a complex organization of structures, which are controlled by various biomechanical and biochemical mechanisms. Among others, these include the actinomyosin cytoskeletal system, extracellular matrix, intracellular signaling responses mediated by protein kinase C, Rho/Rho kinase, and other biologic factors. This review shall describe the various pathophysiologic mechanisms involved in aqueous humor dynamics.

Heterogeneities of in- and out-flows in the Mediterranean Sea

This paper develops a relatively new concept regarding the outflow of Mediterranean Waters (MWs) through the Strait of Gibraltar. While other papers assume that this outflow is composed of only two MWs, we previously found evidence from a re-analysis of 1980s CTD profiles (profiles collected with conductivity-temperature-depth probes during GIBEX, the Gibraltar Experiment), for two other MWs. We also analysed 2003–2008 time series from two CTDs moored (HYDROCHANGES Programme) at the southern sill of Camarinal and on the shelf of Morocco, and we developed a new concept. East of the Strait, the four MWs roughly lay one above the other, but while progressing westward, the associated isopycnals tilt up southward. In the Strait, the MWs are thus juxtaposed, and they all mix with one of two Atlantic Water components (the inflow acronym is thus AWs), and the outflow is horizontally heterogeneous. West of the Strait, the outflow progressively becomes vertically heterogeneous again, hence splitting into a series of superimposed veins. We compared these CTD time series with one collected at the southern sill of Espartel (University of Malaga, INGRES projects and HYDROCHANGES Programme). Fortunately, the CTDs moored at the two sills were generally along the same streamlines so that the MWs’ evolution could be monitored. We demonstrated the significance of mixing lines computed from two successive records and the possibility of linking two sets of data (such as CTD profiles) collected at different locations along the Strait. The outflow, which does not show any clear seasonal variability before the Strait, strongly mixes with the inflow within the Strait. This is due mainly to the internal tide and, because the inflow is seasonally variable, leads to an outflow that displays marked seasonal and fortnightly variabilities. Both the outflow and the inflow also display marked spatial heterogeneity and both long-term/yearly and short-term/daily temporal variabilities before they mix; thus, accurately predicting the outflow characteristics in the Atlantic Ocean appears almost impossible.Herein, we first propose a fully objective description of the AWs and MWs during two GIBEX campaigns. Where the AWs and the MWs do not markedly mix, they are defined in terms of density and temperature ranges. Where a MW mixes with one of the AWs down to the bottom, the mixing line characteristics allow for that MW to be followed from one section to one downstream and for the validation of our concept: while superimposed east of the Strait, the MWs come to be juxtaposed within the Strait before becoming superimposed again. We also analysed additional CTD time series collected by the University of Malaga on the south and north sides of the southern sill of Espartel. We demonstrate the following: (a) even though the MWs at the sill (E) and on the south side (ES) were roughly the same, the densest ones out-flowed at ES, i.e., at depths shallower than at E, (b) the MWs on the north side (EN) were very different from those at E and each mixed with different AWs, and (c) using the mixing lines computed from each time series, the data recorded at E and ES allow for the retrieval, with good accuracy, of those recorded at Camarinal (C), which is not the case for the data recorded at EN. Finally we emphasise how different the AWs’ heterogeneities are from the MWs’ heterogeneities. The inflow is sucked into the Mediterranean Sea, due to the water budget (E–P) deficit there, and it can be composed of any type of AW present west of the Strait at any time and any specific location. The outflow is a product of the Mediterranean Sea, which is like a machine producing a series of MWs that first circulate as alongslope density currents before entering the Strait in a specific order and at specific locations.Consequently, we attempt to schematise the AWs–MWs mixing processes and our understanding of the outflow dynamics. Notwithstanding the difficulty of the working conditions within such a narrow strait, having up to four MWs outflowing side-by-side and mixing with two AWs that have a heterogeneous and variable distribution clearly leads to spatial and temporal heterogeneities that are actually much larger than the ones that have been observed up to now from a relatively low number of CTD profiles and time series.

Modeling Copper Transport in Saturated Sandy Loam Column

Through the soil column experiments, the migration behavior of heavy metal copper ions in saturated sandy loam is analyzed, and it is found that the inflow solution with high concentration is conducive to the migration of copper ions. In the meantime, the software package of CXTFIT is utilized to conduct fitting for the outflow dynamics of copper ions with deterministic equilibrium model and non-equilibrium two-zone model, and predict the changing process of copper ion concentration at the different depths of soil column over the time. The results show that in the indoor saturated homogeneous conditions, the simulation accuracy of fitting parameters that applied deterministic equilibrium model is higher than that used the non-equilibrium two-zone model. Moreover, the influence of fixed water on the copper ion migration can be ignored.

Chronic cerebrospinal venous insufficiency: masked multimodal imaging assessment

Background: Chronic cerebrospinal venous insufficiency (CCSVI) was implicated in the pathophysiology of multiple sclerosis (MS). Objective: We evaluated neurosonography (NS), magnetic resonance venography (MRV), and transluminal venography (TLV) in subsets of MS patients drawn from a single-center, prospective, case-control study of 206 MS and 70 non-MS volunteers. Methods: As previously reported, findings on high-resolution B-mode NS imaging with color and spectral Doppler of the extracranial and intracranial venous drainage consistent with CCSVI were similar among MS and non-MS volunteers (3.88% vs 7.14%; p = 0.266). Ninety-nine MS participants consented to intravascular contrast-enhanced 3D MRV to assess their major systemic and intracranial venous circulation, and 40 advanced to TLV that included pressure measurements of the superior vena cava, internal jugular, brachiocephalic, and azygous veins. Results: NS findings and MRV patterns were discrepant for 26/98 evaluable subjects, including four with abnormal findings on NS that had normal venous anatomy by MRV. In no instance were TLV pressure gradients indicative of clinically significant functional stenosis encountered. The three imaging approaches provided generally consistent data with discrepancies referable to inherent technique properties. Conclusions: Our findings lend no support for altered venous outflow dynamics as common among MS patients, nor do they likely contribute to the disease process.