Escepticismo y eticidad en la "Fenomenología del espíritu" de Hegel

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An effort to make sense of antisense transcription in bacteria

Analysis of bacterial transcriptomes have shown the existence of a genome-wide process of overlapping transcription due to the presence of antisense RNAs, as well as mRNAs that overlapped in their entire length or in some portion of the 5'- and 3'-UTR regions. The biological advantages of such overlapping transcription are unclear but may play important regulatory roles at the level of transcription, RNA stability and translation. In a recent report, the human pathogen Staphylococcus aureus is observed to generate genome-wide overlapping transcription in the same bacterial cells leading to a collection of short RNA fragments generated by the endoribonuclease III, RNase III. This processing appears most prominently in Gram-positive bacteria. The implications of both the use of pervasive overlapping transcription and the processing of these double stranded templates into short RNAs are explored and the consequences discussed

Waves in nonlinear discrete systems

Depto. de Análisis Matemático y Matemática AplicadaFac. de Ciencias MatemáticasFALSEunpu

Photo-excited semiconductor superlattices as constrained excitable media: Motion of dipole domains and current self-oscillations

A model for charge transport in undoped, photo-excited semiconductor superlattices, which includes the dependence of the electron-hole recombination on the electric field and on the photo-excitation intensity through the field-dependent recombination coefficient, is proposed and analyzed. Under dc voltage bias and high photo-excitation intensities, there appear self-sustained oscillations of the current due to a repeated homogeneous nucleation of a number of charge dipole waves inside the superlattice. In contrast to the case of a constant recombination coefficient, nucleated dipole waves can split for a field-dependent recombination coefficient in two oppositely moving dipoles. The key for understanding these unusual properties is that these superlattices have a unique static electric-field domain. At the same time, their dynamical behavior is akin to the one of an extended excitable system: an appropriate finite disturbance of the unique stable fixed point may cause a large excursion in phase space before returning to the stable state and trigger pulses and wave trains. The voltage bias constraint causes new waves to be nucleated when old ones reach the contact.Comment: 19 pages, 8 figures, to appear in Phys. Rev.

Rotura no traumática de componente cerámica-cerámica en PTC: presentación de un caso y revisión de la literatura.

Las fracturas de los componentes cerámicos empleados en artroplastia total de cadera (ATC) son infrecuentes. El objetivo de nuestro trabajo es presentar un caso de rotura precoz no traumática de componente ce - rámica-cerámica en ATC y revisar la literatura en relación con esta complicación. Se trata de un paciente de 58 años diagnosticado de necrosis avascular de cabeza femoral, fue intervenido mediante ATC, implantándosele un par cerámica-cerámica. A los 4 meses de la intervención, sin antecedente traumático previo, se observó fractura de la cúpula de cerámica de la prótesis. El paciente precisó de recambio protésico, utilizándose el par cerámica-polietileno. La fractura de los componentes del par cerámica- cerámica es poco frecuente. El fallo puede ser debido a un defecto de fabricación o en la colocación del implante. Los pacientes deben ser informados sobre la posibilidad de sufrir esta complicación antes de la implantación de una PTC con par cerámica-cerámica.Fractures of ceramic components used in total hip replacement (THR) are uncommon. To report a case of early non-traumatic rupture ceramic-ceramic component in THR and review the literature regarding this complication. A 58 years diagnosed with avascular necrosis of the femoral head, was operated by THR, a ceramic-on -ceramic. At 4 months after surgery, without previous trauma, fracture was observed ceramic dome of the prosthesis. The patient required replacement, using the ceramic-on-polyethylene. The fracture of ceramic components is rare. The failure may be due to a manufacturing defect or implant placement. Patients should be informed about the possi - bility of having this complication before implantation of a THR ceramic-on-ceramic

Analysis of diachronic relationships in successful and unsuccessful behaviors by world fencing champions using three complementary techniques

The aim of this study was to investigate diachronic relationships in successful and unsuccessful behaviors by world fencing champions using three complementary techniques: T-pattern analysis, lag sequential analysis, and polar coordinate analysis. We employed a nomothetic, point, multidimensional observational design in which we analyzed 24 bouts fenced by six world fencing champions in 2014. The actions were recorded and coded using LINCE software. The results revealed a series of behaviors that were significantly associated with successful outcomes, and also identified actions that contributed to poorer performance. One key conclusion to be drawn from the study is that the use of these complementary techniques is perfectly feasible and holds great potential in the field of sport. Lag sequential analysis of occurrences at lag 0 (co-occurrences) and analysis of basic T-patterns provided tactical insights into the different fencing actions employed. This analysis is focused on the actions and reactions of each fencer and his rival during each exchange. Insights into combat strategy, by contrast, were provided by lag sequential analysis of occurrences at lags -1 to -5 and lags +1 to +5, analysis of T-pattern clusters, and polar coordinate analysis. In the last case, we observed how prospective and retrospective behaviors, reflected in the modification or extension of certain behaviors during each bout, improved the efficacy of actions performed throughout the competition

SU-8 Guiding Layer for Love Wave Devices

SU-8 is a technologically important photoresist used extensively for the fabrication of microfluidics and MEMS, allowing high aspect ratio structures to be produced. In this work we report the use of SU-8 as a Love wave sensor guiding layer which allows the possibility of integrating a guiding layer with flow cell during fabrication. Devices were fabricated on ST-cut quartz substrates with a single-single finger design such that a surface skimming bulk wave (SSBW) at 97.4 MHz was excited. SU-8 polymer layers were successively built up by spin coating and spectra recorded at each stage; showing a frequency decrease with increasing guiding layer thickness. The insertion loss and frequency dependence as a function of guiding layer thickness was investigated over the first Love wave mode. Mass loading sensitivity of the resultant Love wave devices was investigated by deposition of multiple gold layers. Liquid sensing using these devices was also demonstrated; water-glycerol mixtures were used to demonstrate sensing of density-viscosity and the physical adsorption and removal of protein was also assessed using albumin and fibrinogen as model proteins