196 research outputs found
Sobre la distribución geográfica de Scarabaeus (Scarabaeus) aegyptiacus Stolfa, 1938 (Coleoptera: Scarabaeidae): primer registro para el Sáhara Atlántico (suroeste de Marruecos)
Scarabaeus aegyptiacus is a species widely distributed from the Arabian Peninsula to Morocco, occupying mainly arid and desert regions. Despite its wide geographic range, the number of known localities is very low (ten locations) and its populations seem apparently fragmented and spaced. During a recent field survey in southwestern Morocco, we found a population of S. aegyptiacus in a rocky steppe (hamada) near Msied (Tan-Tan province, Guelmin-Smara region), which constitutes the first record from Atlantic Sahara and extends about 1000 km to the southwest its known distribution. The specimens were found in a water cistern (“matfiya” in the local language), infrastructure that acts as a deadly trap for many animals, especially reptiles, amphibians and epigean arthropods, whose negative effect on invertebrate communities has not yet been evaluated. Chorological information of the species is synthesized and data on the habitat are provided.Scarabaeus aegyptiacus es una especie ampliamente distribuida desde la Península Arábiga hasta Marruecos, ocupando ambientes áridos y desérticos. A pesar de su amplio rango de distribución, el número de localidades precisas conocidas es muy escaso (diez localidades) y sus poblaciones se encuentran aparentemente fragmentadas y muy distanciadas entre sí. Durante muestreos recientes en el suroeste de Marruecos, hemos hallado una población de S. aegyptiacus en una estepa pedregosa (hamada) en las cercanías de Msied (provincia de Tan-Tan, región de Guelmín-Smara), que constituye el primer registro para el Sáhara Atlántico y amplía unos 1000 km hacia el suroeste su área de distribución conocida. Los individuos estudiados fueron hallados en el interior de un aljibe (“matfiya” en lengua local), infraestructura que actúa como trampa mortal para numerosos animales, especialmente anfibios, reptiles y artrópodos epígeos, cuyo impacto negativo sobre las comunidades de invertebrados no ha sido evaluado. Se sintetiza la información corológica disponible y se aportan datos sobre el hábitat de la especie
Mechanisms of dexamethasone-mediated chemokine down-regulation in mild and severe acute pancreatitis
AbstractThis study aimed to investigate the role of therapeutic dexamethasone (Dex) treatment on the mechanisms underlying chemokine expression during mild and severe acute pancreatitis (AP) experimentally induced in rats. Regardless of the AP severity, Dex (1 mg/kg), administered 1 h after AP, reduced the acinar cell activation of extracellular signal-regulated kinase (ERK) and c-Jun-NH2-terminal kinase (JNK) but failed to reduce p38-mitogen-activated protein kinase (MAPK) in severe AP. In both AP models, Dex inhibited the activation of nuclear factor-kappaB (NF-κB) and signal transducers and activators of transcription (STAT) factors. All of this resulted in pancreatic down-regulation of the chemokines monocyte chemoattractant protein-1 (MCP-1) and cytokine-induced neutrophil chemoattractant (CINC). Lower plasma chemokine levels as well as decreased amylasemia, hematocrit and plasma interleukin-1β (Il-1β) levels were found either in mild or severe AP treated with Dex. Pancreatic neutrophil infiltration was attenuated by Dex in mild but not in severe AP. In conclusion, by targeting MAPKs, NF-κB and STAT3 pathways, Dex treatment down-regulated the chemokine expression in different cell sources during mild and severe AP, resulting in decreased severity of the disease
Stark Widths of Na IV Spectral Lines
Sodium is a very important element for the research and analysis of astrophysical, laboratory, and technological plasmas, but neither theoretical nor experimental data on Stark broadening of Na IV spectral lines are present in the literature. Using the modified semiempirical method of Dimitrijević and Konjević, here Stark widths have been calculated for nine Na IV transitions. Na IV belongs to the oxygen isoelectronic sequence, and we have calculated Stark widths belonging to singlets, triplets, and quintuplets, as well as with different parent terms. This is used to discuss similarities within one transition array with different multiplicities and parent terms. Additionally, calculated widths will be implemented in the STARK-B database (http://stark-b.obspm.fr) which is also a part of the Virtual Atomic and Molecular Data Center (VAMDC—http://www.vamdc.org/
Simple and analytical function for the Stark profile of the Hα line and its application to plasma characterization
The increasing application of plasma based technologies over a wide range of fields has led to the necessity of an optimal determination of the characteristic parameters of the plasma systems. Optical Emission Spectroscopy techniques have been proved as an excellent tool to that end. These techniques are based on the collection and analysis of the radiation coming from the plasma, being classified between molecular and atomic emission. Among atomic emission lines, Hydrogen Balmer series lines are the most measured. The Hβ line is usually the most employed one for plasma diagnosis but under some conditions, the Hβ line is not always detectable and only the Hα line can be detected. For these lines, it is well known that their shapes are the result of the convolution of three profile types: Lorentzians, Gaussians and Starks. But while the first two types present analytical functions, models explaining the Stark profile do not offer these. So, in this paper we propose an accurate analytical function for the Stark profile of the Hα line allowing improving the determination of characteristic parameters of plasma with respect to the methods traditionally used
Using ion beams to tune the nanostructure and optical response of co-deposited Ag : BBBN thin films
The present study is devoted to co-deposited Ag : BN nanocermet thin films and is focused on the influence of ion irradiation conditions on their structural and linear optical properties. Ion irradiation was performed in situ during the growth of the nanocermets using a 50 eV assistance beam (nitrogen/argon or nitrogen-ion assistance) and ex situ on as-grown films using a 120 keV argon-ion beam (post-irradiation). Grazing incidence small-angle x-ray scattering measurements show that (i) as-grown N-assisted films contain prolate spheroidal clusters (height-to-diameter ratio H/D ≈ 1.8), (ii) N/Ar-ion assistance leads to the formation of more elongated clusters (H/D ≈ 2.1) and (iii) post-irradiation leads to a decrease of H/D to a value close to 1. These results are discussed on the basis of atomic diffusion processes involved during the growth of the nanocermets and during the post-irradiation. The optical transmittance spectra of these films measured at normal incidence display one absorption band, due to the excitation of the (1,1) plasmon mode of the clusters. In the case of the as-grown films, an additional band appears at oblique incidence for P-polarized light, as a consequence of the excitation of the (1,0) plasmon mode of the clusters. Our results show that the spectral position of the absorption bands (which can be tuned in the 400-600 nm range) depends on the H/D ratio of the clusters, in good agreement with calculations of optical transmittance considering the nanocomposite layer as a uniaxial anisotropic medium whose dielectric tensor is described by an anisotropic Maxwell-Garnett model. © 2007 IOP Publishing Ltd.The authors would like to thank CNRS-CSIC and Picasso programmes for financial support which permitted the collaboration between the Instituto de Ciencia de Materiales de Sevilla (Spain) and the Laboratoire de Metallurgie Physique ´ de Poitiers (France). The authors also thank J P Simon and the D2AM staff at the ESRF for their support during the GISAXS measurements.Peer Reviewe
Using the Pairs of Lines Broadened by Collisions with Neutral and Charged Particles for Gas Temperature Determination of Argon Non-Thermal Plasmas at Atmospheric Pressure
The spectroscopic method for gas temperature determination in argon non-thermal plasmas sustained at atmospheric pressure proposed recently by Spectrochimica Acta Part B 129 14 (2017)—based on collisional broadening measurements of selected pairs of argon atomic lines, has been applied to other pairs of argon atomic lines, and the discrepancies found in some of these results have been analyzed. For validation purposes, the values of the gas temperature obtained using the different pairs of lines have been compared with the rotational temperatures derived from the OH ro-vibrational bands, using the Boltzmann-plot techniqu
A simple and accurate analytical model of the Stark profile and its application to plasma characterization
Optical Emission Spectroscopy techniques are among the most employed to perform the characterization of laboratory plasmas. The analysis of the obtained data is based on the convolution of three different types of profiles: Lorentzians, Gaussians and Starks. While analytic expressions are available for the first two types, the Stark profile has been traditionally obtained through theoretical calculations using different models. In this paper, we propose is a simple and accurate analytical function that can be employed as approximation of a Stark profile. The application of this new model may simplify the analysis of plasmas
Haemophilus parasuis
The expression of chemokines (CCL-2 and CXCL-8) and cytokines (IL-1α, IL-1β, IL-6, TNF-α, and IL-10) was evaluated by RT-qPCR in colostrum-deprived pigs vaccinated and challenged with Haemophilus parasuis serovar 5. Two vaccines containing native proteins with affinity to porcine transferrin (NPAPTim and NPAPTit) were tested, along with two control groups: one inoculated with PBS instead of antigen (challenge group (CHG)), and another one nonimmunized and noninfected (blank group). The use of NPAPTim and NPAPTit resulted in complete protection against H. parasuis (no clinical signs and/or lesions), and both vaccines were capable of avoiding the expression of the proinflammatory molecules to levels similar to physiological values in blank group. However, overexpression of all proinflammatory molecules was observed in CHG group, mainly in the target infection tissues (brain, lungs, and spleen). High expression of CCL-2, CXCL-8, IL-1α, IL-1β, and IL-6 can be considered one of the characteristics of H. parasuis infection by serovar 5
Assessment by immunoproteomic study of the immune response developed by different subunit vaccines against glässer's disease
Comunicaciones a congreso
PM10 source apportionment in the surroundings of the San Vicente del Raspeig cement plant complex in southeastern Spain
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