1,038 research outputs found
Ancient Martian Floods in a Plausible Variable Climatic Environment as Revealed from the Sequential Growth of Allan Hills 84001 Carbonate Globules
No abstract available
Ancient Martian Floods in a Plausible Variable Climatic Environment as Revealed from the Sequential Growth of Allan Hills 84001 Carbonate Globules
No abstract available
Increased cerebrospinal fluid levels of cytokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1β (MIP-1β) in patients with amyotrophic lateral sclerosis
Introduction: Neuroinflammation has recently been described in amyotrophic lateral sclerosis
(ALS). However, the precise role of such proinflammatory cytokines as monocyte chemoattractant
protein-1 (MCP-1) and macrophage inflammatory protein-1� (MIP-1�) in ALS has not yet
been determined. In this study, we determined cerebrospinal fluid (CSF) MCP-1 and MIP-1�
levels and assessed their association with the duration and severity of ALS.
Methods: Concentrations of MCP-1 and MIP-1� were determined in the CSF of 77 patients
diagnosed with ALS and 13 controls. Cytokine levels were analysed in relation to ALS duration
( 12 months) and severity ( 30 points on the ALS Functional Rating
Scale administered at hospital admission).
Results: Higher CSF MIP-1� (10.68 pg/mL vs 4.69 pg/mL, P < .0001) and MCP-1 (234.89 pg/mL
vs 160.95 pg/mL, P = .011) levels were found in the 77 patients with ALS compared to controls.
There were no differences in levels of either cytokine in relation to disease duration or severity.
However, we did observe a significant positive correlation between MIP-1� and MCP-1 in patients
with ALS.
Conclusions: The increase in MIP-1� and MCP-1 levels suggests that these cytokines may havea synergistic effect on ALS pathogenesis. However, in our cohort, no association was found witheither the duration or the clinical severity of the disease
First Principle Local Density Approximation Description of the Electronic Properties of Ferroelectric Sodium Nitrite
The electronic structure of the ferroelectric crystal, NaNO, is studied
by means of first-principles, local density calculations. Our ab-initio,
non-relativistic calculations employed a local density functional approximation
(LDA) potential and the linear combination of atomic orbitals (LCAO). Following
the Bagayoko, Zhao, Williams, method, as enhanced by Ekuma, and Franklin
(BZW-EF), we solved self-consistently both the Kohn-Sham equation and the
equation giving the ground state charge density in terms of the wave functions
of the occupied states. We found an indirect band gap of 2.83 eV, from W to R.
Our calculated direct gaps are 2.90, 2.98, 3.02, 3.22, and 3.51 eV at R, W, X,
{\Gamma}, and T, respectively. The band structure and density of states show
high localization, typical of a molecular solid. The partial density of states
shows that the valence bands are formed only by complex anionic states. These
results are in excellent agreement with experiment. So are the calculated
densities of states. Our calculated electron effective masses of 1.18, 0.63,
and 0.73 mo in the {\Gamma}-X, {\Gamma}-R, and {\Gamma}-W directions,
respectively, show the highly anisotropic nature of this material.Comment: 13 Pages, 4 Figures, and 2 Table
Anormalidades clÃnicas y por resonancia magnética en lengua de pacientes con esclerosis lateral amiotrófica
Vertical distribution of PAHs in marine sediments (particulate fraction and interstitial water) from eight Iberian Mediterranean areas
Polycyclic aromatic hydrocarbons (PAHs) have been determined in sediment cores from eight Iberian Mediterranean coastal areas (Barcelona, Tarragona, Ebro Delta, Valencia, Castellón, Cartagena, AlmerÃa y Málaga), considering both interstitial water and solid fraction. Three sediment cores were taken in three different sampling sites per area by using a box corer. Cores were cut into 1-cm-thick sections between 0 and 18-cm depth, interstitial water was obtained by centrifugation and samples from every site were pooled. Fourteen polycyclic aromatic hydrocarbons (fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, crysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[g,h,i]perylene, dibenzo[a,h]anthracene and indeno[1,2,3-c,d]pyrene) were determined in interstitial water by stir bar sorptive extraction coupled to GC/MS and solid fraction by Soxhlet extraction and HPLC with fluorescence detection. As result of PAHs hydrofobicity, their concentrations were several magnitude order higher in sediment (solid phase) than interstitial water. Total PAH concentration in sediment varied from 1 to 1321 g•kg-1 d.w and from 4.9 to 274 ng•L-1 in interstitial water. Vertical PAHs distributions in sediments were homogeneous in some areas, however, sharp concentration decreases were observed at deeper layers from some sampling sites. However, their maximum concentrations in interstitial water were found mainly in upper or in deeper layers, depending on the specific characteristics of the area and sediments.This work was supported by the Spanish Ministry of Environment (2-ESMARME and 2-2-ESMARME projects), the Spanish Inter-Ministerial Science and Technology Commission through the ‘IMPACTA’ (CICYT, CTM2013-48194-C3-1-R) project and the European Union through the European Regional Development Fund (ERDF)
Sea snail (Hexaplex trunculus) and sea cucumber (Holothuria polii) as potential sentinel species for organic pollutants and trace metals in coastal ecosystems
Postprin
Incremento de las citoquinas proteÃna quimiotáctica de monocitos-1 (MCP-1) y proteÃna inflamatoria macrofágica-1β (MIP-1β) en lÃquido cefalorraquÃdeo de pacientes con esclerosis lateral amiotrófica
Introducción: En la esclerosis lateral amiotrófica (ELA) se ha descrito recientemente
la presencia de neuroinflamación. Sin embargo, no se ha definido el rol de citoquinas
proinflamatrorias como la proteÃna quimiotáctica de monocitos-1 (MCP-1) y
la proteÃna inflamatoria macrofágica-1� (MIP-1�) en ELA. En este estudio evaluamos
niveles de MCP-1 y MIP-1� en lÃquido cefalorraquÃdeo (LCR), analizando su participación en
la duración y gravedad de la ELA.
Métodos: En 77 pacientes con ELA definida y 13 sujetos controles, se comparó el nivel de
citoquinas MCP-1 y MIP-1� en LCR. Se analizaron estos niveles con relación a la duración de
la ELA ( 12 meses) y a la gravedad de esta determinada mediante el puntaje
obtenido al ingreso en la escala funcional estratificada de la ELA ( 30 puntos).
Resultados: En los 77 pacientes con ELA, se encontraron aumentados los niveles de MIP-1�
(4,69 pg/ml vs. 10,68 pg/ml, p < 0,0001) y MCP-1 (160,95 pg/ml vs. 234,89 pg/ml, p = 0,011) en
comparación con sujetos controles. No se observó diferencia de los niveles de estas citoquinas
con la duración o la gravedad de la enfermedad. Sin embargo, observamos una correlación
positiva significativa entre MIP-1� y MCP-1 en pacientes con ELA.
Conclusiones: El aumento de MIP-1� y MCP-1 sugiere que estas citoquinas parecen tener unefecto sinérgico en la patogénesis de la ELA. Sin embargo, en nuestra cohorte no se asociaroncon la duración o la gravedad de la ELA
Levels and spatial distribution of organochlorinated compounds and polycyclic aromatic hydrocarbons in fishes from a Mediterranean coastal lagoon
The seasonal input and distribution of organic contaminants in the Mar Menor lagoon have been recently characterized in seawater and sediments, showing the significant impact of flash flood events. Mar Menor is a hypersaline (42-47 psu) coastal lagoon located in the Cartagena Field area at the South East of Spain subjected mainly to intensive agriculture, seasonal tourism and recreational activities. The bioaccumulation of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorinated pesticides (OCPs) has been also determined in bivalves, but no information was available about their accumulation in fishes. In this study the concentrations of PAHs, PCBs and OCPs in golden grey mullet (Liza aurata) and red mullet (Mullus barbatus) muscle were determined. Their spatial distribution throughout the Mar Menor lagoon was characterized considering 9 sampling areas and two different sampling periods, spring and autumn in 2010 for golden grey mullet and only one (autumn) for red mullet. PAHs and organochlorinated pollutants were extracted using specific Soxhlet procedures. After cleanup and purification steps the final extracts were analyzed by HPLC for PAHs, and by GC-MS for PCBs and OCPs. The higher concentrations of all pollutants were found close to main urban and port areas of this lagoon and in the influence area of El Albujón watercourse. PAHs concentrations (sum of 14 congeners) in both species varied between 1 and 20.7 g/kg w.w. being pyrene and phenanthrene the most abundant ones. p,p’DDE showed higher concentrations than PAHs in golden grey mullet (concentration range: 0.2-32.7 g/kg w.w.), specially close to the main navigation channel between this lagoon and the Mediterranean Sea.This work has been supported by the Spanish Inter-Ministerial Science and Technology Commission through ‘DECOMAR’ project (CICYT, CTM2008-01832) and by Seneca Foundation (Region of Murcia, Spain) through ‘BIOMARO’ project (15398/PI/10). Rubén Moreno-González wishes to thank the Spanish Ministry of Science and Innovation for the FPI grant (BES 2009-014713)
Interchange Slip-Running Reconnection and Sweeping SEP Beams
We present a new model to explain how particles (solar energetic particles;
SEPs), accelerated at a reconnection site that is not magnetically connected to
the Earth, could eventually propagate along the well-connected open flux tube.
Our model is based on the results of a low-beta resistive magnetohydrodynamics
simulation of a three-dimensional line-tied and initially current-free bipole,
that is embedded in a non-uniform open potential field. The topology of this
configuration is that of an asymmetric coronal null-point, with a closed fan
surface and an open outer spine. When driven by slow photospheric shearing
motions, field lines, initially fully anchored below the fan dome, reconnect at
the null point, and jump to the open magnetic domain. This is the standard
interchange mode as sketched and calculated in 2D. The key result in 3D is
that, reconnected open field lines located in the vicinity of the outer spine,
keep reconnecting continuously, across an open quasi-separatrix layer, as
previously identified for non-open-null-point reconnection. The apparent
slipping motion of these field lines leads to form an extended narrow magnetic
flux tube at high altitude. Because of the slip-running reconnection, we
conjecture that if energetic particles would be traveling through, or be
accelerated inside, the diffusion region, they would be successively injected
along continuously reconnecting field lines that are connected farther and
farther from the spine. At the scale of the full Sun, owing to the super-radial
expansion of field lines below 3 solar radii, such energetic particles could
easily be injected in field lines slipping over significant distances, and
could eventually reach the distant flux tube that is well-connected to the
Earth
- …