2,156 research outputs found
Diseño de una guía metodológica de diagnóstico y gestión del control en áreas de TI, utilizando MSV y COBIT
Con este trabajo integrador, se busca brindar a las organizaciones una herramienta
para el diagnóstico y la gestión del control al interior de las áreas de TI, buscando
establecer mecanismos que contribuyan a la viabilidad del área de TI, y, por ende,
contribuyan al fortalecimiento de la organización.
Para tal fin, se parte de los conocimientos adquiridos a los largo de la especialización,
haciendo principalmente uso de los modelos de Planeación Estratégica [1], el Modelo
del Sistema Viable [17] y el marco de referencia COBIT [12], aprovechando las
fortalezas que tienen estas herramientas y complementándolas entre si, para obtener
un producto final útil a las organizaciones en el entorno actual
Causes and consequences of purifying selection on SARS-CoV-2
Owing to a lag between a deleterious mutation’s appearance and its selective removal, gold-standard methods for mutation rate estimation assume no meaningful loss of mutations between parents and offspring. Indeed, from analysis of closely related lineages, in SARS-CoV-2, the Ka/Ks ratio was previously estimated as 1.008, suggesting no within-host selection. By contrast, we find a higher number of observed SNPs at 4-fold degenerate sites than elsewhere and, allowing for the virus’s complex mutational and compositional biases, estimate that the mutation rate is at least 49–67% higher than would be estimated based on the rate of appearance of variants in sampled genomes. Given the high Ka/Ks one might assume that the majority of such intrahost selection is the purging of nonsense mutations. However, we estimate that selection against nonsense mutations accounts for only ∼10% of all the “missing” mutations. Instead, classical protein-level selective filters (against chemically disparate amino acids and those predicted to disrupt protein functionality) account for many missing mutations. It is less obvious why for an intracellular parasite, amino acid cost parameters, notably amino acid decay rate, is also significant. Perhaps most surprisingly, we also find evidence for real-time selection against synonymous mutations that move codon usage away from that of humans. We conclude that there is common intrahost selection on SARS-CoV-2 that acts on nonsense, missense, and possibly synonymous mutations. This has implications for methods of mutation rate estimation, for determining times to common ancestry and the potential for intrahost evolution including vaccine escape
Transcription, mRNA export, and immune evasion shape the codon usage of viruses
The nucleotide composition, dinucleotide composition, and codon usage of many viruses differ from their hosts. These differences arise because viruses are subject to unique mutation and selection pressures that do not apply to host genomes; however, the molecular mechanisms that underlie these evolutionary forces are unclear. Here, we analyzed the patterns of codon usage in 1,520 vertebrate-infecting viruses, focusing on parameters known to be under selection and associated with gene regulation. We find that GC content, dinucleotide content, and splicing and m(6)A modification-related sequence motifs are associated with the type of genetic material (DNA or RNA), strandedness, and replication compartment of viruses. In an experimental follow-up, we find that the effects of GC content on gene expression depend on whether the genetic material is delivered to the cell as DNA or mRNA, whether it is transcribed by endogenous or exogenous RNA polymerase, and whether transcription takes place in the nucleus or cytoplasm. Our results suggest that viral codon usage cannot be explained by a simple adaptation to the codon usage of the host—instead, it reflects the combination of multiple selective and mutational pressures, including the need for efficient transcription, export, and immune evasion
Beetles (Coleoptera) of Peru: A Survey of the Families. Scarabaeoidea
The 1042 species of Scarabaeoidea known to occur in Peru are listed with their taxonomic placement in families, subfamilies, and tribes
Insertion of isocyanides into zirconium-alkyl bonds of di-ansa-zirconocene complexes. X-ray molecular structure of [Zr{(SiMe2)2(η5-C5H3))Cl(η2-C(i-Pr)N(2,6-Me2C6H3)}]
New dicyclopentadienyl iminoacyl zirconium complexes have been prepared and characterized by NMR spectroscopy. The reaction of [Zr{SiMe2)2(η5-C5H3)2)Me2] with CNR (R 2,6-Me2C6H3, t-Bu) yields [Zr((SiMe2)2(η5-C5H3)2Me(η2-CMeNR)] (R = 2,6-Me2C6H3, t-Bu), which reacts with a stoichiometric amount of water to give the μ-oxo dimers [Zr{(SiMe2)2(η5-C5H3)2}(η2-CMeNR)]2(μ-O) (R = 2,6-Me2C6H3, t-Bu). The chloro neophyl complex [Zr{(SiMe2)2(η5-C5H3)2}Cl(CH2CMe2Ph)] and other β-hydrogen containing zirconium chloro alkyls [Zr{(SiMe2)2(η5-C5H3)2}CIR] (R Et, n-Pr, i-Pr)_ with CN(2,6-Me2C6H3) to yield the related chloro iminoacyl complexes [Zr{(SiMe2)2(η5-C5H3)2)Cl}η2-CRN(2,6-Me2C6H3)}] (R Et, n-Pr, i-Pr), whereas no reaction was observed when CN(t-Bu) was used. All the new iminoacyl complexes were characterized by 1H and 13C NMR spectroscopy and the X-ray molecular structure of [Zr{(SiMe2)2(η5-C5H3)2)Cl{η2-C(i-Pr)N(2,6-Me2C6H3)}] studied by diffraction methods to prove the expected ‘inside’ coordination of the iminoacyl nitrogen atom.BID-CONICIT (Venezuela)Comunidad Autónoma de Madri
Evidence for strong mutation bias towards, and selection against, U content in SARS-CoV-2: implications for vaccine design
Mechanisms of Degradation and Identification of Connectivity and Erosion Hotspots
The context of processes and characteristics of soil erosion and land degradation in Mediterranean lands is outlined. The concept of connectivity is explained. The remainder of the chapter demonstrates development of methods of mapping, analysis and modelling of connectivity to produce a spatial framework for development of strategies of use of vegetation to reduce soil erosion and land degradation. The approach is applied in a range of typical land use types and at a hierarchy of scale from land unit to catchment. Patterns of connectivity and factors influencing the location and intensity of processes are identified, including the influence of topography, structures such as agricultural terraces and check dams, and past land uses. Functioning of connectivity pathways in various rainstorms is assessed. Modes of terrace construction and extent of maintenance, as well as presence of tracks and steep gradients are found to be of importance. A method of connectivity modelling that incorporates effects of structure and vegetation was developed and has been widely applied subsequently
TiO2 Modification with Transition Metallic Species (Cr, Co, Ni, and Cu) for Photocatalytic Abatement of Acetic Acid in Liquid Phase and Propene in Gas Phase
The commercial P25 titania has been modified with transition metallic species (Cr, Co, Ni, and Cu), added by impregnation with aqueous solutions of the corresponding nitrates. The preparation procedure also includes a heat treatment (500 °C) in argon to decompose the nitrates, remove impurities and to strengthen the metal–TiO2 interaction. The catalysts have been thoroughly characterized using N2 adsorption, scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-visible diffuse-reflectance spectroscopy (UV-vis DRS) and X-ray photoelectron spectroscopy (XPS), and have been tested in the aqueous phase decomposition of acetic acid and in the gas phase oxidation of propene, using an irradiation source of 365 nm in both cases. The photocatalytic activity of the four metal-containing catalysts varies with the nature of the metallic species and follows a similar trend in the two tested reactions. The effect of the nature of the added metallic species is mainly based on the electrochemical properties of the supported species, being Cu/P25 (the sample that contains copper) the best performing catalyst. In the photodecomposition of acetic acid, all the metal-containing samples are more active than bare P25, while in the gas phase oxidation of propene, bare P25 is more active. This has been explained considering that the rate-determining steps are different in gas and liquid media.This research was funded by MINECO and FEDER, project of reference CTQ2015-66080-R, GV/FEDER (PROMETEO/2018/076) and University of Alicante (VIGROB-136)
Using the emotional functioning in clinical practice to detect psychological distress in patients with advanced thoracic and colorectal cancer
Purpose: Patients with advanced cancer suffer significant decline of their psychological state. A rapid and reliable evaluation of this state is essential to detect and treat it and improve quality of life. The aim was to probe the usefulness of the emotional function (EF) subscale of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EF-EORTC-QLQ-C30) to assess psychological distress in cancer patients. Methods: This is a multicenter, prospective, observational study involving 15 Spanish hospitals. Patients diagnosed with unresectable advanced thoracic or colorectal cancer were included. Participants completed the Brief Symptom Inventory 18 (BSI-18), the current the gold standard, and the EF-EORTC-QLQ-C30 to assess their psychological distress prior to initiating systemic antineoplastic treatment. Accuracy, sensitivity, positive predictive value (PPV), specificity, and negative predictive value (NPV) were calculated. Results: The sample comprised 639 patients: 283 with advanced thoracic cancer and 356 with advanced colorectal cancer. According to the BSI scale, 74% and 66% displayed psychological distress with an EF-EORTC-QLQ-C30 accuracy of 79% and 76% in detecting psychological distress in individuals with advanced thoracic and colorectal cancer, respectively. Sensitivity was 79 and 75% and specificity was 79 and 77% with a PPV of 92 and 86% and a NPV of 56 and 61% (scale cut-off point, 75) for patients with advanced thoracic and colorectal cancer, respectively. The mean AUC for thoracic cancer was 0.84 and, for colorectal cancer, it was 0.85. Conclusion: This study reveals that the EF-EORTC-QLQ-C30 subscale is a simple and effective tool for detecting psychological distress in people with advanced cancer
M/TiO2 photocatalysts for the abatement of pollutants in gaseous and liquid effluents
Comunicación presentada en 13th European Congress on Catalysis, EuropaCat, Florence, Italy, 27 August-01 September 2017.The authors thank MINECO (CTQ2015-66080-R), Generalitat Valenciana /Feder (PROMETEOII/2014/010) and Universidad de Alicante (VIGROB-136) for financial support
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