Synthesis, physicochemical and photophysical characterization of 4-(1-Pyrenyl)-Butyl-α-d-mannopyranoside

Indexación: Web of Science; Scopus; Scielo.Glycolipids are biomolecules composed of a lipid chain (lipophilic) and a monosaccharide or oligosaccharide as hydrophilic group. Their chemical structure and biological role make them undoubtedly good candidates for a large and continuously growing number of biotechnological applications. Mannose is a carbohydrate present on membrane glycolipids of a wide number of pathogenic microorganisms (bacteria, fungi, protozoa, and viruses) and specifically recognized by several lectins. We synthesized a mannose derivative linked through a short methylene chain to a pyrene moiety which behaves as a surfactant, able to aggregate, and retains the photophysical properties of pyrene: showing comparable absorption and emission spectra, having lower fluorescence quantum yield and the ability to form excimer, and finally the ability to produce O-2((1)Delta(g)) with high quantum yields. Thus, this novel molecule would open future applications for detection (fluorescence) or inactivation (singlet oxygen) of bacterial pathogens, viruses, tumor cells, or particular cells.http://ref.scielo.org/pcn4d

Análisis del cumplimiento tributarío, la gestión y control de las cuentas de gastos de una empresa que produce y comercializa fundas y zunchos para banano ubicada en el cantón Pascuales durante el ejercicio fiscal 2008

The main intention of this tesina is to verify that the company has fulfilled suitably the tributary obligations, having correctly provisionado the risks derived from possible fiscal contingencies. In order to fulfill the proposed objective one took place the planning, programming and application of the audit tests, the same ones that helped us to the Service to the revision of the tributary declarations presented/displayed by the company of Internal Rents and to be able to determine the consistency of this information. Soon we elaborated necessary the internal controls for each test of audit that we carried out, with the intention that the company can have a suitable tributary fulfillment

Poetry – Minimal Anthology

This volume carries the major distinction of being the only existing English translation of Fernando Pessoa’s poems to recreate both the rhyme and the metrical schemes of the original

Doping fingerprints of spin and lattice fluctuations in moiré superlattice systems

Twisted Van der Waals systems offer the unprecedented possibility to tune different states of correlated quantum matter with external noninvasive electrostatic doping. The nature of the superconducting order presents a recurring open question in this context. In this work, we assess quantitatively the case of spin-fluctuation-mediated pairing for Γ-valley twisted transition metal dichalcogenide homobilayers. We calculate self-consistently and dynamically the doping-dependent superconducting transition temperature Tc revealing a superconducting dome with a maximal Tc≈0.1–1K depending on twist angle. We compare our results with conventional phonon-mediated superconductivity, and we identify clear fingerprints in the doping dependence of Tc, which enable experiments to distinguish between different pairing mechanisms

Critical Strain Region Evaluation of Self-Assembled Semiconductor Quantum Dots

A novel peak finding method to map the strain from high resolution transmission electron micrographs, known as the Peak Pairs method, has been applied to In(Ga) As/AlGaAs quantum dot (QD) samples, which present stacking faults emerging from the QD edges. Moreover, strain distribution has been simulated by the finite element method applying the elastic theory on a 3D QD model. The agreement existing between determined and simulated strain values reveals that these techniques are consistent enough to qualitatively characterize the strain distribution of nanostructured materials. The correct application of both methods allows the localization of critical strain zones in semiconductor QDs, predicting the nucleation of defects, and being a very useful tool for the design of semiconductor device

Evaluación del cribado y la efectividad de una intervención breve en bebedores de riesgo atendidos en consultas de atención primaria

ObjetivosEvaluar el cribado y la efectividad de una intervención breve antialcohólica, el grado de aceptación y la evolución de los parámetros biológicos asociados con el consumo de alcohol tras la intervención.DiseñoEstudio prospectivo longitudinal de intervención de 1 año de duración.EmplazamientoCinco consultas de atención primaria urbanas.ParticipantesDe una muestra aleatoria de 681 sujetos de ambos sexos y de edad de 18-65 años, se seleccionó a 78 bebedores de riesgo. Los que cumplían criterios de exclusión (n=10), no aceptaban participar (n=24) y presentaban sospecha de síndrome de dependencia alcohólica (n=11) no participaron en el estudio.IntervencionesSe ofrecía un breve consejo antialcohólico apoyado con soporte escrito, y se realizaba un seguimiento a los 2 y 12 meses mediante la cuantificación del consumo de alcohol y un control analítico.Mediciones principalesSe estimó la prevalencia de bebedores de riesgo, el grado de aceptación a participar en el estudio, la disminución del consumo de alcohol y de bebedores de riesgo a los 2 y 12 meses, y la evolución de los parámetros analíticos tras la intervención.ResultadosLa prevalencia de bebedores de riesgo fue del 11,5% (intervalo de confianza [IC] del 95%, 8,3-14,7%). El grado de aceptación a participar en el estudio fue del 64,7%. Se observó un decremento significativo (p<0,05) en el consumo de alcohol a los 2 y 12 meses, así como una disminución de los bebedores de riesgo, que a los 2 meses fue del 57,6% (IC del 95%, 50,3-64,9%; p=0,01) y a los 12 meses del 42,4% (IC del 95%, 35,9-48,9%; p=0,003). Asimismo, se produjeron disminuciones significativas en las concentraciones de GGT, VCM, colesterol y triglicéridos.ConclusionesSe observa una baja prevalencia de bebedores de riesgo sin sospecha de síndrome de dependencia alcohólica en nuestro medio, así como una elevada efectividad del consejo breve antialcohol y del grado de aceptación a participar en el estudio. Se apreció una disminución de las concentraciones de GGT, VCM, colesterol y triglicéridos tras la intervención.AimsTo evaluate the screening, the effectiveness of an antialcoholic brief intervention for risk drinkers, the acceptation level to participate in this study, and the analytical parameters evolution associated to the alcohol consumption after of the intervention.DesignLongitudinal prospective intervention study of 1 year of duration.Setting5 urban primary care physician's practices.ParticipantsOf an aleatory pattern of 681 patients, men and women of 18-65 years old, were selected 78 risk drinkers. Patients with exclusion criteria (n=10), didn’t wanted to participate (n=24) and had suspicion of alcoholic dependence syndrome (ADS) (n=11), didn’t participated in this intervention.InterventionsWere offered antialcoholic brief counselling with written supporter and were followed with alcohol consumption rate and analytical control at 2 and 12 months.Main measuresWas estimated the prevalence of risk drinkers, the acceptation level to participate in this study, alcohol consumption and risk drinkers decreased at 2 and 12 months, analytical parameters evolution after of the intervention.ResultsPrevalence of risk drinkers: 11.5% (95% confidence interval [CI], 8.3%-14.7%). Acceptation level to participate in this study: 64.7%. Significative alcohol consumption decreased at 2 and 12 months (P<.05). Risk drinkers decreased: at 2 months were 57.6% (95% CI, 50.3%-64.9%; P=.01) and at 12 months were 42.4% (95% CI; 35.9%-48.9%) (P=.003). GGT, MCV, cholesterol, and triglycerides significative decreased.ConclusionsLow prevalence of risk drinkers without suspicion of ADS in our setting; high effectiveness of antialcoholic brief counselling and high acceptation level to participate in this study; reduction of the GGT, MCV, cholesterol, and triglycerides after of the intervention

Switching and growth for microbial populations in catastrophic responsive environments

Phase variation, or stochastic switching between alternative states of gene expression, is common among microbes, and may be important in coping with changing environments. We use a theoretical model to assess whether such switching is a good strategy for growth in environments with occasional catastrophic events. We find that switching can be advantageous, but only when the environment is responsive to the microbial population. In our model, microbes switch randomly between two phenotypic states, with different growth rates. The environment undergoes sudden "catastrophes", the probability of which depends on the composition of the population. We derive a simple analytical result for the population growth rate. For a responsive environment, two alternative strategies emerge. In the "no switching" strategy, the population maximises its instantaneous growth rate, regardless of catastrophes. In the "switching" strategy, the microbial switching rate is tuned to minimise the environmental response. Which of these strategies is most favourable depends on the parameters of the model. Previous studies have shown that microbial switching can be favourable when the environment changes in an unresponsive fashion between several states. Here, we demonstrate an alternative role for phase variation in allowing microbes to maximise their growth in catastrophic responsive environments.Comment: 9 pages, 10 figures; replaced with revised versio