102 research outputs found
Partial Sequencing of the Mitocondrial Genome of the Buzzatii Cluster of Drosophila
[Resumen]
En una tesis doctoral desarrollada por Luís Rodríguez López (2015) se cruzaron recíprocamente dos cepas diferentes de Drosophila buzzatii. La distribución sexual de la descendencia muestra evidencia inviabilidad parcial de los machos en uno de los dos sentidos de cruzamiento, debido posiblemente a un efecto materno asociado a la transmisión de una variante mitocondrial. En el presente proyecto se amplificó, secuenció y analizó una región determinada de genoma mitocondrial procedente de cada linaje. Contiene parte de los genes ND4 y CYTB, los genes completos ND4L y ND6, y las secuencias tRNA-thr y tRNA-pro. Se pretendía con su análisis la aproximación al origen de las diferencias del genoma mitocondrial causantes de esa inviabilidad, ya sea descartando o hallando distancias nucleotídicas en el fragmento escogido. La región de estudio también se comparó entre las especies del cluster Drosophila buzzatii. Se obtuvo así evidencia definitiva de que el genoma mitocondrial de una de las cepas utilizadas en la tesis doctoral anteriormente mencionada se corresponde con el de la especie D. koepferae. Revisando bibliográficamente su procedencia se sabe que en el origen de dicha cepa hay un cruzamiento de hembras de la especie D. koepferae con machos de la especie D. buzzatii. Se concluye entonces que las diferencias que se buscaban no obedecen a un polimorfismo nucleotídico de D. buzzatii, sino a que en uno de los linajes se heredó por vía materna el genoma mitocondrial de D. koepferae.[Resumo]
Nunha tese doutoral desenvolvida por Luís Rodríguez López (2015) cruzáronse recíprocamente dúas cepas diferentes de Drosophila buzzatii. A distribución sexual da descendencia mostra evidencias de inviabilidade parcial dos machos nun dos dous sentidos de cruzamento, debido posiblemente a efeccto materno asociado á transmisión dunha variante mitocondrial. No presente proxecto se amplificou, secuenciou e analizou unha rexión determinada de xenoma mitocondrial procedente de cada linaxe. Contén parte dos xenes ND4 e CYTB, os xenes completos ND4L e ND6, e as secuencias de ARNt-thr e ARNt pro. Preténdese coa súa análise a aproximación á orixe das diferenzas do xenoma mitocondrial causantes desta inviabilidade, xa sexa descartando ou atopando diferenzas nucleotídicas no fragmento escollido. A rexión de estudo tamén comparou entre as especies do clúster Drosophila buzzatii. Obtivose así evidencia definitiva de que o xenoma mitocondrial dunha das cepas utilizadas na tese doutoral anteriormente mencionada se corresponde co da especie D. koepferae. Revisando bibliográficamente a súa procedencia se sabe que na orixe de dita cepa hai un cruzamento de hembras da especie D. koepferae con machos da especie D. buzzatii. Conclúese entón que as diferenzas que se buscan non obedecen a un polimorfismo nucleotídico de D. buzzatii, senón a que nunha das liñas herdouse por vía materna o xenoma mitocondrial de D. koepferae.[Abstract]
In a doctoral thesis written by Luis Rodriguez Lopez (2015), were reciprocally crossed two different Drosophila buzzatii strains. The sexual distribution of the offspring shows evidence of partial infeasibility of the males in one of the two crossing directions, possibly due to a maternal effect associated with the transmission of a mitochondrial variant. In the present project, a specific region of mitochondrial genome from each lineage has been amplified, sequenced and analyzed. It contains part of the ND4 and CYTB genes, the complete sequence of ND4L and ND6 genes, and the tRNA-thr and tRNA-pro sequences. Analysis intends to approximate the origin of the differences in the mitochondrial genome that caused this infeasibility, either by ruling out or finding nucleotide differences in the chosen fragment. The study region was also compared between the species in the Drosophila buzzatii cluster. Thus, it was obtained that mitochondrial genome of one of the strains used in the aforementioned doctoral thesis corresponds to that of the species D. koepferae. Bibliographically reviewing its provenance, it is known that at the origin of this strain there is a crossbreeding of females of the species D. koepferae with males of the species D. buzzatii. It was then concluded that differences were sought were not due to a D. Buzzatii’s nucleotide polymorphism, but rather that the mitochondrial genome of D. koepferae was inherited maternally in one of the lineages.Traballo fin de grao (UDC.CIE). Bioloxía. Curso 2019/202
Enzymatic cometabolic biotransformation of organic micropollutants in wastewater treatment plants: a review
Biotransformation of trace-level organic micropollutants (OMPs) by complex microbial communities in wastewater treatment facilities is a key process for their detoxification and environmental impact reduction. Therefore, understanding the metabolic activities and mechanisms that contribute to their biotransformation is essential when developing approaches aiming to minimize their discharge. This review addresses the relevance of cometabolic processes and discusses the main enzymatic activities currently known to take part in OMPs removal under different redox environments in the compartments of wastewater treatment plants. Furthermore, the most common methodologies to decipher such enzymes are discussed, including the use of in vitro enzyme assays, enzymatic inhibitors, the analysis of transformation products and the application of several -omic techniques. Finally, perspectives on major challenges and future research requirements to improve OMPs biotransformation are proposedThis research was funded by the Spanish Government (Agencia Estatal de Investigación) through the ANTARES project (PID2019-110346RB-C21) and a PhD Xunta de Galicia Grant (ED481A-2018/113, David Kennes). Authors from Universidade de Santiago de Compostela belong to Galician Competitive Research Group (GRC ED431C 2017/29), which is co-funded by FEDER (EU)S
Molecular diversity and selective sweeps in Iberian honey bee
Deciphering the genetic basis of the process of adaptation of organisms has been
and remains one of the fundamental goals of evolutionary biology. Genomes contain
information related to the history of natural populations. The Iberian honey bee (Apis
mellifera iberiensis Engel 1999) exhibits a complex genetic diversity pattern of clinal variation
shaped not only by evolutionarily neutral processes but also by selection. Unravelling the
variation of subgenomic regions in this subspecies not only allows us to better understand
the complexity of clinal patterning, but also the identification of genetic variation involved
in local adaptation.
Several regions related to vision, xenobiotic detoxification, and immune response have
shown signals of selection in A. m. iberiensis. In this study, analyses of sequence variation
around candidate subgenomic regions (~100 kpb) have been carried out. The aims of this
work are to provide further evidence of positive selection in the Iberian honey bee, to
localize at a much finer scale the direct points of such selection, and to find the underlying
source of the beneficial alleles or variants.info:eu-repo/semantics/publishedVersio
Fluorescence of methylated derivatives of hydroxyphenylimidazopyridine. Resolution of strongly overlapping spectra and a new ESIPT dye showing very efficient radiationless deactivation
This is the peer-reviewed version of the following article:
Fluorescence of methylated derivatives of hydroxyphenylimidazopyridine.
Resolution of strongly overlapping spectra and a new ESIPT dye showing very efficient
radiationless deactivation
Alfonso Brenlla, Manoel Veiga, M. Carmen Ríos Rodríguez, Manuel Mosquera and
Flor Rodríguez-Prieto
Photochem. Photobiol. Sci., 2011, 10, 1622. DOI: 10.1039/c1pp05165b, which has been
published in final form at http://pubs.rsc.org/en/content/articlelanding/2011/pp/c1pp05165b
This article may be used for non-commercial purposes onlyThe ground- and excited-state behaviour of the isomeric species 2-(2′-methoxyphenyl)imidazo[4,5-b]pyridine (1-OMe) and 2-(2′-hydroxyphenyl)-4-methylimidazo[4,5-b]pyridine (1-NMe) in neutral and acid media has been studied by UV-vis absorption spectroscopy, steady-state and time-resolved fluorescence spectroscopy. The new dye 1-NMe is non-fluorescent in neutral media except in trifluoroethanol, where it shows a very weak fluorescence. 1-NMe also exhibits highly solvent-dependent fluorescence intensity in acidic media. We propose that the neutral species experiences a fast excited-state intramolecular proton transfer (ESIPT), relaxing afterwards by intramolecular twisting associated with internal charge transfer (TICT) and subsequent very fast internal conversion of the proton-transferred TICT structure. The behaviour of 1-NMe in acidic media is explained by the existence of a ground-state tautomeric equilibrium between species with intramolecular hydrogen bonds N–H⋯OH and N⋯HO. The first type of tautomers dissociates at the hydroxyl group in water and ethanol, but fluoresces in acetonitrile and trifluoroethanol due to the inability of these solvents to accept the proton. The second type of tautomers is non-emissive due to fast radiationless deactivation through an ESIPT-TICT process. The fluorescence of 1-OMe was investigated in neutral and acidic media, demonstrating the photobasic character of the pyridine nitrogen. A ground-state equilibrium between pyridinium and imidazolium cations was found for this species, showing overlapping absorption and fluorescence spectra. We devised a method to resolve the spectra by applying principal component global analysis to a series of excitation spectra taken at different emission wavelengths, which allowed estimation of the equilibrium constant between the cationsWe are indebted to the Spanish Ministry of Education and Science and the European Regional Development Fund (Grants CTQ2007-68057-C02-01/BQU and CTQ2010-17835) and the Xunta de Galicia (Grant IN845B-2010/094) for financial support of our work. A. Brenlla thanks the Fundación Segundo Gil Dávila for a postgraduate research
grantS
Application of decomposition techniques in a wildfire suppression optimization model
Resource assignment and scheduling models provides an automatic and fast decision support system for wildfire suppression logistics. However, this process generates challenging optimization problems in many real-world cases, and the computational time becomes a critical issue, especially in realistic-size instances. Thus, to overcome that limitation, this work studies and applies a set of decomposition techniques such as augmented Lagrangian, branch and price, and Benders decomposition’s to a wildfire suppression model. Moreover, a reformulation strategy, inspired by Benders’ decomposition, is also introduced and demonstrated. Finally, a numerical study comparing the behavior of the proposals using different problem sizes is conductedThis research work is supported by the R+D+I project grants PID2020-116587GB-I00 and PID2021-124030NB (C31 and C32), funded by MCIN/AEI/10.13039/501100011033/ and by “ERDF A way of making Europe”/EU. Second author investigation is funded by the Xunta de Galicia (contract post-doctoral 2019-2022). We acknowledge the computational resources provided by CESGA. Third author acknowledges support from the Xunta de Galicia through the ERDF (ED431C-2020-14 and ED431G 2019/01), and “CITIC”S
Decentralized and collaborative machine learning framework for IoT
Decentralized machine learning has recently been proposed as a potential solution to the security issues of the canonical federated learning approach. In this paper, we propose a decentralized and collaborative machine learning framework specially oriented to resource-constrained devices, usual in IoT deployments. With this aim we propose the following construction blocks. First, an incremental learning algorithm based on prototypes that was specifically implemented to work in low-performance computing elements. Second, two random-based protocols to exchange the local models among the computing elements in the network. Finally, two algorithmics approaches for prediction and prototype creation. This proposal was compared to a typical centralized incremental learning approach in terms of accuracy, training time and robustness with very promising results.Axencia Galega de Innovación | Ref. 25/IN606D/2021/2612348Agencia Estatal de Investigación | Ref. PID2020-113795RB-C3
Frequency of lower extremity artery disease in type 2 diabetic patients using pulse oximetry and the ankle-brachial index
Observational study[Abstract] Objectives: To determine the of undiagnosed lower extremity artery disease using the pulse oximetry in a type 2 diabetic population sample.
Methods: Observational, cross-sectional, descriptive study that included 594 type 2 diabetic patients, with no previous history of lower extremity artery disease. Medical history, physical examination, determination of the ankle-brachial index (portable Doppler) and measurement of oxygen saturation in upper and lower extremities (pulse oximeter) were performed.
Results: Frequency of lower extremity artery disease determined by ankle-brachial index was 18.4%. No significant correlations were detected between oxygen saturation and the ankle-brachial index except for the relationship between ankle-brachial index vs. oxygen saturation at 30 cm lower limb elevation vs. the supine position at no elevation (0 cm) in subjects under the age of 40. Pulse oximetry showed little diagnostic value in the screening of lower extremity artery disease. A relationship between lower extremity artery disease and age has been found. Its diagnosis was associated with a lower body mass index and lower systolic blood pressure in the lower extremities and higher in the upper extremities.
Conclusions: We conclude that pulse oximetry is not useful in the screening for asymptomatic lower extremity artery disease in type 2 diabetics
Response to deep brain stimulation in three brain targets with implications in mental disorders: a PET study in rats
Objective: To investigate metabolic changes in brain networks by deep brain stimulation (DBS) of the medial prefrontal cortex (mPFC), nucleus accumbens (NAcc) and dorsomedial thalamus (DM) using positron emission tomography (PET) in naïve rats. Methods: 43 male Wistar rats underwent stereotactic surgery and concentric bipolar platinum-iridium electrodes were bilaterally implanted into one of the three brain sites. [18F]-fluoro-2-deoxy-glucose-PET (18FDG-PET) and computed tomography (CT) scans were performed at the 7th (without DBS) and 9th day (with DBS) after surgery. Stimulation period matched tracer uptake period. Images were acquired with a small-animal PET-CT scanner. Differences in glucose uptake between groups were assessed with Statistical Parametric Mapping. Results: DBS induced site-specific metabolic changes, although a common increased metabolic activity in the piriform cortex was found for the three brain targets. mPFC-DBS increased metabolic activity in the striatum, temporal and amygdala, and reduced it in the cerebellum, brainstem (BS) and periaqueductal gray matter (PAG). NAcc-DBS increased metabolic activity in the subiculum and olfactory bulb, and decreased it in the BS, PAG, septum and hypothalamus. DM-DBS increased metabolic activity in the striatum, NAcc and thalamus and decreased it in the temporal and cingulate cortex. Conclusions: DBS induced significant changes in 18FDG uptake in brain regions associated with the basal ganglia-thalamo-cortical circuitry. Stimulation of mPFC, NAcc and DM induced different patterns of 18FDG uptake despite interacting with the same circuitries. This may have important implications to DBS research suggesting individualized target selection according to specific neural modulatory requirements.This research was conducted under the EraNet Neuron framework (DBS_F20rat) and supported by the Federal Ministry of Education and Research, Germany (BMBF 01EW1103), the Ministry of Economy and Competitiveness ISCIII-FIS grants (PI14/00860, CPII/00005) co-financed by ERDF (FEDER) Funds from the European Commission, "A way of making Europe", Fundación Mapfre and Comunidad de Madrid (BRADE S2013/ICE-2958)
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