Search results for "DEPLETION"

Headache in cerebrospinal fluid volume depletion syndrome: A case report

2006

Cerebrospinal fluid (CSF) volume depletion syndrome is due to leakage of cerebrospinal fluid through lesions of the dural sac at the level of the cranial base or of the spine. When past medical history is negative for recent trauma or surgery, the term spontaneous intracranial hypotension (SIH) is used. SIH is characterized clinically by orthostatic headache, neck pain, nausea, emesis, horizontal diplopia, tinnitus, plugged ear, hearing difficulties, blurring of vision, facial numbness, and upper limb radicular symptoms. In SIH, brain and cervical MR scans show a diffuse pachymeningeal gadolinium enhancement that ends at the site of CSF leakage. The application of epidural blood patches has…

Material flows, efficiency and decoupling: Latvia's case study

2019

Latvia with its growing economy and intensive use of biomass is one of the biggest per capita natural resource consumers in Europe. If current patterns of resource use are maintained, environmental degradation and depletion of natural resources will continue. This paper looks at the resource flows in Latvia (1995 to 2016) - the country that does not have fossil energy resource deposits and timber industry is an important economic sector contributing most to the direct material input. It analyses the main resource flows, its intensities and looks at the main drivers behind these changes. Results demonstrate that resource extraction and consumption is steadily increasing and are not decoupled…

Emission of bromine and iodine from Mount Etna volcano

2005

[1] Constraining fluxes of volcanic bromine and iodine to the atmosphere is important given the significant role these species play in ozone depletion. However, very few such measurements have been made hitherto, such that global volcanic fluxes are poorly constrained. Here we extend the data set of volcanic Br and I degassing by reporting the first measurements of bromine and iodine emissions from Mount Etna. These data were obtained using filter packs and contemporaneous ultraviolet spectroscopic SO2 flux measurements, resulting in time-averaged emission rates of 0.7 kt yr−1 and 0.01 kt yr−1 for Br and I, respectively, from April to October 2004, from which we estimate global Br and I flu…

Ozone depletion in tropospheric volcanic plumes

2010

Ground based remote sensing techniques are used to measure volcanic SO2 fluxes in efforts to characterise volcanic activity. As these measurements are made several km from source there is the potential for in-plume chemical transformation of SO2 to sulphate aerosol (conversion rates are dependent on meteorological conditions), complicating interpretation of observed SO2 flux trends. In contrast to anthropogenic plumes, SO2 lifetimes are poorly constrained for tropospheric volcanic plumes, where the few previous loss rate estimates vary widely (from 99% per hour). We report experiments conducted on the boundary layer plume of Masaya volcano, Nicaragua during the dry season. We found that SO2…

Modelling molecular iodine emissions in a coastal marine environment: The link to new particle formation

2006

International audience; A model of iodine chemistry in the marine boundary layer (MBL) has been used to investigate the impact of daytime coastal emissions of molecular iodine (I2). The model contains a full treatment of gas-phase iodine chemistry, combined with a description of the nucleation and growth, by condensation and coagulation, of iodine oxide nano-particles. In-situ measurements of coastal emissions of I2 made by the broadband cavity ring-down spectroscopy (BBCRDS) and inductively coupled plasma-mass spectrometry (ICP/MS) techniques are presented and compared to long path differential optical absorption spectroscopy (DOAS) observations of I2 at Mace Head, Ireland. Simultaneous me…

Commentary: Misguided Effort with Elusive Implications, and Sifting Signal from Noise with Replication Science

2016

On Capturing Oil Rents with a National Excise Tax Revisited

2004

In this paper the scope of Bergstrom’s (1982) results is studied. Moreover, his analysis is extended assuming that extraction cost is directly related to accumulated extractions. For the case of a competitive market it is found that the optimal policy is a constant tariff if extraction is costless. However, with depletion effects, the optimal tariff must ultimately be decreasing. For the case of a monopolistic market the results depend crucially on the kind of strategies the importing country governments can play and on whether the monopolist chooses the price or extraction rate. For a price-setting monopolist it is shown that the importing countries cannot use a tariff to capture monopoly …

Human γδ T-Cells: From Surface Receptors to the Therapy of High-Risk Leukemias

2018

γδ T lymphocytes are potent effector cells, capable of efficiently killing tumor and leukemia cells. Their activation is mediated by γδ T-cell receptor (TCR) and by activating receptors shared with NK cells (e.g., NKG2D and DNAM-1). γδ T-cell triggering occurs upon interaction with specific ligands, including phosphoantigens (for Vγ9Vδ2 TCR), MICA-B and UL16 binding protein (for NKG2D), and PVR and Nectin-2 (for DNAM-1). They also respond to cytokines undergoing proliferation and release of cytokines/chemokines. Although at the genomic level γδ T-cells have the potential of an extraordinary TCR diversification, in tissues they display a restricted repertoire. Recent studies have identified …

Distribution and depletion of sulfadiazine after a multiple per os dosing in gilthead sea bream (Sparus aurata) fed two different diets

2013

The distribution and depletion profile of sulfadiazine (SDZ) were investigated in gilthead sea bream (Sparus aurata) fed on fish oil (FO) or plant oil-based (PO) diets. Fish averaging 230 g were given medicated feed containing 25 mg SDZ kg-1 fish for 5 days at 24-26°C. Blood and muscle plus skin were sampled on days 1, 3, 5, 6, 8 and 9. Differences in plasma and fillet SDZ levels between the two groups were statistically insignificant. The maximum drug concentrations in plasma were 3.2 ± 1.9 μg mL-1 and 2.9 ± 1.2 μg mL-1 in the PO and FO groups, respectively. In post-medicated samples depletion rapidly reached concentrations close to the level of quantification at 72 h post medication. With…

Angiotensin II-Stoffwechsel bei Angiotensininfusion und bei Kochsalzentzug

1975

1. Bei funf normotonen Probanden wurde im arteriellen und venosen Plasma des Unterarms vor und nach diatetischem Salzentzug sowie vor und wahrend Infusion von Angiotensin II-amid Angiotensin II (A II) und der Angiotensinmetabolit Angiotensin (3–8)-Hexapeptid (H) nach dunnschichtchromatographischer Trennung radioimmunologisch bestimmt.