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VEM-window data are shown to distinguish among key rock types on Venus, and evaluate redox state and transition metal contents of Venus surface rocks.

Intracellular calcium elevation triggers a wide range of cellular responses. Calcium responses can be affected or modulated by membrane receptors mutations, localization, exposure to agonists/antagonists, among others ( Burgos et al., 2007 ; Martínez et al., 2016 ). Changes in intracellular calcium concentration can be measured using the calcium sensitive fluorescent ratiometric dye fura-2 AM. This method is a high throughput way to measure agonist mediated calcium responses.

We investigate the importance of cash flows as opposed to discount rates to the pricing of assets that, unlike common stock, are thinly traded but have reliable cash flow information. We rely on the dynamic Gordon model, which we adapt to deal with the thin trading environment, by developing a self-propagating rolling VAR. Using data from the CMBS market, we find that cash flows are informative in valuing these thinly traded assets. Predicted yields resemble transaction yields and outperform yields based on matrix prices, especially when cash flows are more volatile, and therefore more informative.

Patients with acutely treated femoral shaft fractures with reamed intramedullary nailing are at risk for acute respiratory distress syndrome due to liberation of bone marrow fat particles that travel to the lung and cause damage to the parenchyma. The purpose of this study was to demonstrate: (1) the ability of clinically applicable embolic protection devices to capture such particles; (2) how such a device affects cardiopulmonary function after reamed intramedullary nailing; and (3) evaluation of lung pathology to determine whether filtration affects pulmonary embolic load.A total of 12 canines were anesthetized, and hemodynamic monitoring was established. Carotid embolic protection devices were introduced into the iliac vein, and ipsilateral intramedullary reaming and nailing was performed. Cardiopulmonary parameters were recorded at timed intervals up to 60 minutes after the procedure. The control group (n = 4) was compared with groups treated with Accunet (n = 4) and Spider (n = 4) filters. A blinded histopathological review was performed on lung specimens to determine the average number of emboli per section and to measure the area (mm(2)) of embolic load by digital image analysis.Gross inspection of the embolic protection devices showed the presence of bone marrow debris. A significant change was observed in pH levels (control = -0.052, filters = +0.005; P .05) within the 60 minutes after intramedullary nailing. Serum bicarbonate (meq/dL) values were noted to have similar changes of -2.7 and -1.8 at 10 and 60 minutes, whereas the experimental group was +0.6 and +0.8 at the same time intervals (P =.01 and .0004, respectively). Pulmonary measurements for pO2 and oxygen saturation were analogous to the serum parameters with decreases in the control group in comparison with the filter groups. The mean numbers of emboli and area measurements of embolic load were significantly reduced in the filter group (all P .01).Embolic protection devices were effective in capturing embolic debris from reamed intramedullary nailing of lower extremity long bones and demonstrated a protective effect on pulmonary function and significantly decreased the number and size of emboli in the lung. Based on these findings, patients with long bone fractures at risk for pulmonary complications and acute respiratory distress syndrome could benefit from the placement of embolic protection devices prior to intramedullary fixation. While this study utilized filtration devices designed for carotid embolic protection, further study is warranted to determine optimal filter design in this setting.

High-resolution ultrasonography can help clinicians visualize key anatomic structures of the elbow and guide periarticular and intra-articular injections. Historically, most procedures done around the elbow have been done using landmark guidance, and few studies have reported the accuracy of ultrasonography-guided injections in the elbow region. This article reviews common musculoskeletal disorders about the elbow that can be evaluated with ultrasonography, reviews the literature on ultrasonography-guided injections of the elbow region, and describes the senior author's preferred approach for the most commonly performed elbow region injections.

Photon Homodyne Spectroscopy (HCS) and Laser Doppler Velocimetry (LDV) have been used to study turbulent velocity fluctuations V(R) associated with eddies of size R. For small R both types of measurement were consistent with a model in which the active regions of turbulence He on a fractal of dimension D, with D increasing from ~ 2 to ~ 3 as the Reynolds number (Re) increases above some threshold value. At larger eddy sizes, the LDV measurements show a different scaling of the velocity fluctuations. We associate these larger eddies with the energy reservoir that feeds the inertial cascade.

Posttraumatic headaches (PTHs) are one of the most frequently reported symptoms after a sport concussion, and treatment options for chronic PTH are limited. In this report, we present a case of a 17-year-old boy with persistent PTH after a sport concussion successfully treated with an intranasal sphenopalatine block.

A temperature rise on the order of tenths of a degree is observed as one fluid spreads over a hygroscopic fluid. While this behavior is only exhibited with hygroscopic fluids, it is independent of the properties of the spreading fluid. The spreading induces a ‘rolling’ motion in the subphase which brings ‘fresh’ fluid to the surface, exposing it to the water vapor in the air. As water is absorbed into the hygroscopic liquid, heat is released. The same behavior is observed whether the spreading fluid has a spreading monolayer that drives a convection front or is a spreading lens with a moving three-phase contact line.

This paper proposes a new methodology for decomposing real estate investment trust (REIT) dividends into discretionary and nondiscretionary components. By examining the tax characteristics of dividends, I am able to accurately measure the discretionary component of a REIT's dividend. This methodology provides new insights into our understanding of REIT dividend payout policy. Unlike previous studies that find limited explanations for discretionary dividend payouts, I find a systematic explanation. Discretionary dividends tend to be large on average making up between 18% and 35% of a REIT's total dividend and display considerable variation through time and across firms. The main determinant of these discretionary dividends appears to be dividend smoothing. There is an inverse relationship between discretionary and nondiscretionary dividends. Even if a REIT has excess cash flow it could distribute in discretionary dividends, it will tend not to do so if it has a high dividend payout due to its nondiscretionary dividends. In this sense, REITs appear to use discretionary dividends to smooth their payout ratios.

This article tests the ability of traditional capital structure theories to explain the issuance decisions of real estate investment trusts (REITs). For issuances made between 1997 and 2006, we find strong support for the market timing theory of capital structure. Controlling for past returns and growth, a REIT is more likely to issue equity when its price-to–net asset value ratio is high. This suggests that REITs issue equity in public markets when the cost of equity capital is lower in the public market than in the private market. Consistent with traditional market timing, REITs are more likely to issue equity after experiencing large price increases. We also find some support for REITs following the trade-off theory of capital structure. REITs are less likely to issue debt when proxies for expected bankruptcy costs are high.

The alveolar epithelium plays a critical role in resolving pulmonary edema. We thus hypothesized that its function might be upregulated in rats with heart failure, a condition that severely challenges the lung's ability to maintain fluid balance. Heart failure was induced by left coronary artery ligation. Echocardiographic and cardiovascular hemodynamics confirmed its development at 16 wk postligation. At that time, alveolar fluid clearance was measured by an increase in protein concentration over 1 h of a 5% albumin solution instilled into the lungs. Baseline alveolar fluid clearance was similar in heart failure and age-matched control rats. Terbutaline was added to the instillate to determine whether heart failure rats responded to β-adrenoceptor stimulation. Alveolar fluid clearance in heart failure rats was increased by 194% after terbutaline stimulation compared with a 153% increase by terbutaline in control rats. To determine the mechanisms responsible for this accelerated alveolar fluid clearance, we measured ion transporter expression (ENaC, Na-K- ATPase, CFTR). No significant upregulation was observed for these ion transporters in the heart failure rats. Lung morphology showed significant alveolar epithelial type II cell hyperplasia in heart failure rats. Thus, alveolar epithelial type II cell hyperplasia is the likely explanation for the increased terbutaline-stimulated alveolar fluid clearance in heart failure rats. These data provide evidence for previously unrecognized mechanisms that can protect against or hasten resolution of alveolar edema in heart failure.

Cholesterol modulates the plasmalemma's biophysical properties and influences the function and trafficking of membrane proteins. A fundamental phenomenon that remains obscure is how the plasmalemma's lipid composition regulates the activatable pool of membrane receptors. An outstanding model to study this phenomenon is the nicotinic acetylcholine receptor (nAChR), since the nAChR activatable pool has been estimated to be but a small fraction of the receptors present in the plasmalemma. Studies on the effect of cholesterol depletion in the function of the Torpedo californica nAChR, using the lipid-exposed nAChR mutation (alpha C418W) that produces a congenital myasthenic syndrome (CMS), demonstrated that cholesterol depletion causes a remarkable increase in the alpha C418W nAChR's macroscopic current whereas not in the wild-type (WT). A variety of approaches were used to define the mechanism responsible for the cholesterol depletion mediated-increase in the alpha C418W nAChR's macroscopic current. The present study suggests that a substantial fraction of the alpha C418W nAChRs is located in caveolin-1-positive domains, "trapped" in a non-activatable state, and that membrane cholesterol depletion results in the relocation of these receptors to the activatable pool. Co-fractionation and co-immunoprecipitation of the alpha C418W nAChR and the membrane raft protein caveolin-1 (cav1) support the notion that interactions at lipid-exposed domains regulate the partition of the receptor into membrane raft microdomains. These results have potential implications as a novel mechanism to fine-tune cholinergic transmission in the nervous system and in the pathogenesis associated to the alpha C418W nAChR.

Receptor desensitization, or decreased responsiveness of a receptor to agonist stimulation, represents a regulatory process with the potential to have a significant impact on cell behavior. P2Y(2), a G-protein-coupled receptor activated by extracellular nucleotides, undergoes desensitization at many tissues, including the vascular endothelium. Endothelial cells from a variety of vascular beds are normally exposed to extracellular nucleotides released from damaged cells and activated platelets. The purpose of the present study was to compare P2Y(2) receptor desensitization observed in endothelial cells derived from bovine retina, a model of microvascular endothelium, and human umbilical vein endothelial cells (HUVECs), a model of a large blood vessel endothelium. P2Y(2) receptor desensitization was monitored by following changes in UTP-stimulated intracellular free Ca(2 +) in single cells using fura-2 microfluorometry. Both endothelial cell models exhibited desensitization of the P2Y(2) receptor after stimulation with UTP. However, the cells differed in the rate, dependence on agonist concentration, and percentage of maximal desensitization. These results suggest differential mechanisms of P2Y(2) receptor desensitization and favors heterogeneity in extracellular nucleotide activity in endothelial cells according to its vascular bed origin.

International audience; Based on experience gained from using the VIRTIS instrument on VenusExpress to observe the surface of Venus and the new high temperature laboratory exper- iments, we have developed the multi-spectral Venus Emissivity Mapper (VEM) to study the surface of Ve- nus. VEM imposes minimal requirements on the spacecraft and mission design and can therefore be added to any future Venus mission. Ideally, the VEM instrument will be combined with a high-resolution radar mapper to provide accurate topographic infor- mation, as it is done on the VERITAS mission

This paper investigates the aquifer system and groundwater quality of Okrika Island using lithological logs, static water level (SWL) measurements and physico-chemical analyses of sampled waters from ten boreholes. The borehole logs identify three (3) major lithologies within the Benin Formation. These include clayey sand, clay and sand. The clays are silty in places, while the sands are fine to coarse and poorly sorted. In some boreholes, clays occur as topsoil and could be up to 9 m thick. In the other boreholes, the topsoils are either sand or clayey sand. Two main sand aquifer units were delineated. The static water levels are relatively shallow (o.5 7.9 m) making the aquifers in the area vulnerable to pollution from solid wastes and leachates. The pH values vary from 6.6 7.7 with an average of 7.1 which indicate slightly acidic to slightly basic groundwater. The concentrations of chloride are between 10 and 300 mg/L with a mean of 92.28 mg/L. Total alkalinity values are between 81 and 86 mg/L. Ironconcentrations range from 0.01 0.1 mg/L with an average of 0.04 mg/L. Sulphate concentration ranges from 0.02 20 mg/L. These values are low when compared with the WHO (2006) standard for potable water. The calcium hardness obtained falls between 10 and 62 mg/L. Magnesium hardness is low in the water and ranges in concentration between 6 and 17 mg/L while total hardness values of the groundwater samples in the area range from 2.5 100 mg/L, indicating that the water is soft to moderately hard. The bicarbonate concentration measured at Isaka II is 81mg/L while the total dissolved solids (TDS) values fall between 10 300 mg/L. Except at few locations where elevated chloride concentrations were recorded, the groundwater is generally potable.Keywords: Water Quality, Hydrogeology, Saline Water Intrusion, Okrika Island, Niger Delta.