748 research outputs found
Prenatal diagnosis and follow-up of congenital splenic cysts
Los quistes esplĂŠnicos congĂŠnitos son entidades poco
frecuentes, particularmente en la edad pediĂĄtrica. En la literatura
especializada existen pocos casos publicados con
diagnĂłstico durante el perĂodo prenatal.
Los autores describen 2 casos clĂnicos, identificados por
ecografĂa prenatal a las 34 y 30 semanas de gestaciĂłn, y su
evoluciĂłn posnatal hasta su resoluciĂłn espontĂĄnea a los
5 meses y a los 2 aĂąos de vida, respectivamente.
Se revisa la etiologĂa, clĂnica y evoluciĂłn de esta patologĂa.Congenital splenic cysts are uncommon entities, especially
in children. Few cases diagnosed in the prenatal period
have been reported in the literature.
We describe two cases that were identified by prenatal
sonography at 34 and 30 gestational weeks. Their follow-
up until spontaneous full regression at 5 months and
2 years, respectively, is discussed.
The etiology, clinical findings, and clinical course of this
entity are reviewed
A likely magnetic activity cycle for the exoplanet host M dwarf GJ 3512
Current radial velocity data from specialized instruments contain a large
amount of information that may pass unnoticed if their analysis is not
accurate. The joint use of Bayesian inference tools and frequency analysis has
been shown effective to reveal exoplanets but they have been used less
frequently to investigate stellar activity. We intend to use radial velocity
data of the exoplanet host star GJ 3512 to investigate its magnetic activity.
Our study includes the analysis of the photometric data available. The main
objectives of our work are to constrain the orbital parameters of the
exoplanets in the system, to determine the current level of activity of the
star and to derive an activity cycle length for it. An adaptive importance
sampling method was used to determine the parameters of the exoplanets orbit.
Generalized Lomb-Scargle periodograms were constructed with both radial
velocity curve and photometric data. A careful analysis of the harmonic
frequencies was conducted in each periodogram. Our fit to multiple Keplerian
orbits constrained the orbital parameters of two giant gas planets orbiting the
star GJ 3512. The host star showed an increase of its magnetic activity during
the last observing campaign. The accurate fit of the radial velocity curve data
to the multi-Keplerian orbit permitted to reveal the star rotation in the
residuals of the best fit and estimate an activity cycle length of ~ 14 years.Comment: Accepted for publication in the Astronomical Journal. 15 pages, 11
figure
Introducing Fiji and ICY image processing techniques in ichnological research as a tool for sedimentary basin analysis
Some features of trace fossils are not easy to determine due to limited vissibility of trace fossils. Here, we applied two image processing techniques (Fiji and ICY) to ichnological studies and we compare them with the previously used high-resolution image treatment method. , discussing their usefulness for ichnological studies. Then, these are compared with a high resolution image treatment. These techniques are revealed as rapid alternatives for estimation of some ichnological features, being so useful for the first stages of research, when a detailed analysis is not needed
Los boticarios del hospital Real de Santiago de Compostela en el siglo XVIII
The present work tries to illustrate the life and work of the professionals of a Pharmacy at an outstanding Spanish hospital in the 18th century. This centre, founded by the Catholic King and Queen (Fernando of Aragón and Isabel of Castilla) in the late 15th century, will provide the professionals of Pharmacy with an original constitution that shall rule their lives beyond their pharmaceutical activity. The author aims to recreate the figure of the Institution´s Pharmacists, both on their professional aspects and on their projection on the urban society of their time. To do so, different sections focus on the obligations of the Pharmacists as drugs technicians and as Major Ministers of the Institution; Their interaction among the centre sanitary personnel and the conflicts that arise among the different professionals; their formation; their salary —which is compared to those of similar professionals and even with those of other similar Spanish hospitals—, the criteria for their promotion as well as their social origin and consideration their job gives them.El presente trabajo trata de dar a conocer la vida y la actividad de los profesionales de la Botica de un emblemático hospital español durante el siglo XVIII. Este Centro sanitario, fundado por los Reyes Católicos en las postrimerías del siglo XV, dotará a los profesionales de la Botica de unas originales Constituciones que regularán la vida de estos más allá de su tarea farmacéutica. El autor intenta recrear la figura de los Boticarios de la Institución en su vertiente profesional y la que deriva de ésta en el conjunto de la sociedad urbana de su época; para ello se estudian, en distintas secciones, las obligaciones de los Boticarios en tanto que técnicos del medicamento y en su condición de Ministros Mayores del Establecimiento, su engranaje en el entramado sanitario del Centro y los conflictos que aparecen entre los diversos estamentos, su formación, sus sueldos —que se comparan con el de otros profesionales afines y aún con los de otros Hospitales españoles de similares características—, los criterios de su nombramiento así como el origen y la consideración social que su cargo les depara
Cognitive performance and the thymus among HIV-infected subjects receiving HAART
Maria J Miguez-Burbano1, John E Lewis2, Jose Moreno3, Joel Fishman41Robert Stempel School of Public Health & School of Medicine, Florida International University, Miami, FL, USA; 2Department of Psychiatry and Behavioral Sciences, 3Department of Medicine, 4Department of Radiology, University of Miami Miller School of Medicine, Miami, FL, USAObjective: To evaluate the impact of alcohol use, which is widespread in human immunodeficiency virus (HIV)+ individuals, on highly active antiretroviral therapy (HAART)-associated immune and cognitive improvements and the relationship between those two responses.Methods: In a case-control longitudinal study, thymic volume, cognition, and immune responses were evaluated at baseline and after 6 months therapy in HIV+ and HIV- controls. Cognitive performance was evaluated using the HIV Dementia Score (HDS) and the California Verbal Learning Test (CVLT).Results: Prior to HAART, thymic volume varied considerably from 2.7 to 29.3 cm3 (11 ± 7.2 cm3). Thymic volume at baseline showed a significantly inverse correlation with the patient’s number of years of drinking (r2 = 0.207; p < 0.01), as well as HDS and the CVLT scores in both HIV-infected (r2 = 0.37, p = 0.03) and noninfected (r2 = 0.8, p = 0.01). HIV-infected individuals with a small thymic volume scored in the demented range, as compared with those with a larger thymus (7 ± 2.7 vs. 12 ± 2.3, p = 0.005). After HAART, light/moderate drinkers exhibited thymus size twice that of heavy drinkers (14.8 ± 10.4 vs. 6.9 ± 3.3 cm3).Conclusions: HAART-associated increases of thymus volume appear to be negatively affected by alcohol consumption and significantly related to their cognitive status. This result could have important clinical implications.Keywords: thymus, CNS, immune, alcoho
Do cover crops increase or decrease nitrous oxide emissions? A meta-analysis
There are many environmental benefits to incorporating cover crops into crop rotations, such as their potential to decrease soil erosion, reduce nitrate (NO3) leaching, and increase soil organic matter. Some of these benefits impact other agroecosystem processes, such as greenhouse gas emissions. In particular, there is not a consensus in the literature regarding the effect of cover crops on nitrous oxide (N2O) emissions. Compared to site-specific studies, meta-analysis can provide a more general investigation into these effects. Twenty-six peer-reviewed articles including 106 observations of cover crop effects on N2O emissions from the soil surface were analyzed according to their response ratio, the natural log of the N2O flux with a cover crop divided by the N2O flux without a cover crop (LRR). Forty percent of the observations had negative LRRs, indicating a cover crop treatment which decreased N2O, while 60% had positive LRRs indicating a cover crop treatment which increased N2O. There was a significant interaction between N rate and the type of cover crop where legumes had higher LRRs at lower N rates than nonlegume species. When cover crop residues were incorporated into the soil, LRRs were significantly higher than those where residue was not incorporated. Geographies with higher total precipitation and variability in precipitation tended to produce higher LRRs. Finally, data points measured during cover crop decomposition had large positive LRRs and were larger than those measured when the cover crop was alive. In contrast, those data points measuring for a full year had LRRs close to zero, indicating that there was a balance between periods when cover crops increased N2O and periods when cover crops decreased emissions. Therefore, N2O measurements over the entire year may be needed to determine the net effect of cover crops on N2O. The data included in this meta-analysis indicate some overarching crop management practices that reduce direct N2O emissions from the soil surface, such as no soil incorporation of residues and use of nonlegume cover crop species. However, our results demonstrate that cover crops do not always reduce direct N2O emissions from the soil surface in the short term and that more work is needed to understand the full global warming potential of cover crop management
A class of constant modulus algorithms for uniform linear arrays with a conjugate symmetric constraint
A class of constant modulus algorithms (CMAs) subject to a conjugate symmetric constraint is proposed for blind beamforming based on the uniform linear array structure. The constraint is derived from the beamformer with an optimum output signal-to-interference-plus-noise ratio (SINR). The effect of the additional constraint is equivalent to adding a second step to the original adaptive algorithms. The proposed approach is general and can be applied to both the traditional CMA and its all kinds of variants, such as the linearly constrained CMA (LCCMA) and the least squares CMA (LSCMA) as two examples. With this constraint, the modified CMAs will always generate a weight vector in the desired form for each update and the number of adaptive variables is effectively reduced by half, leading to a much improved overall performance. (C) 2010 Elsevier B.V. All rights reserved
Production of functionalized polyhydroxyalkanoates by genetically modified Methylobacterium extorquens strains
<p>Abstract</p> <p>Background</p> <p>Methylotrophic (methanol-utilizing) bacteria offer great potential as cell factories in the production of numerous products from biomass-derived methanol. Bio-methanol is essentially a non-food substrate, an advantage over sugar-utilizing cell factories. Low-value products as well as fine chemicals and advanced materials are envisageable from methanol. For example, several methylotrophic bacteria, including <it>Methylobacterium extorquens</it>, can produce large quantities of the biodegradable polyester polyhydroxybutyric acid (PHB), the best known polyhydroxyalkanoate (PHA). With the purpose of producing second-generation PHAs with increased value, we have explored the feasibility of using <it>M. extorquens </it>for producing functionalized PHAs containing C-C double bonds, thus, making them amenable to future chemical/biochemical modifications for high value applications.</p> <p>Results</p> <p>Our proprietary <it>M. extorquens </it>ATCC 55366 was found unable to yield functionalized PHAs when fed methanol and selected unsaturated carboxylic acids as secondary substrates. However, cloning of either the <it>phaC1 </it>or the <it>phaC2 </it>gene from <it>P. fluorescens </it>GK13, using an inducible and regulated expression system based on cumate as inducer (the cumate switch), yielded recombinant <it>M. extorquens </it>strains capable of incorporating modest quantities of C-C double bonds into PHA, starting from either C6= and/or C8=. The two recombinant strains gave poor results with C11=. The strain containing the <it>phaC2 </it>gene was better at using C8= and at incorporating C-C double bonds into PHA. Solvent fractioning indicated that the produced polymers were PHA blends that consequently originated from independent actions of the native and the recombinant PHA synthases.</p> <p>Conclusions</p> <p>This work constitutes an example of metabolic engineering applied to the construction of a methanol-utilizing bacterium capable of producing functionalized PHAs containing C-C double bonds. In this regard, the PhaC2 synthase appeared superior to the PhaC1 synthase at utilizing C8= as source of C-C double bonds and at incorporating C-C double bonds into PHA from either C6= or C8=. The <it>M. ex-phaC2 </it>strain is, therefore, a promising biocatalyst for generating advanced (functionalized) PHAs for future high value applications in various fields.</p
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