Pembuatan Barium Strontium Titanat (BaxSr1-xTiO3) untuk x<0,5 dan Strontium Titanat Menggunakan Metode Solid State Reaction

Barium Strontium Titanate sample preparation (BaxSr1-xTiO3) for x <0.5 and Strontium Titanate has been carried out using solid state reaction method. Parameters varied in this research is a comparison the number of moles of Ba and Sr are 40:60, 30:70, 20:80, 10:90, and 00:100, and the variation of sintering temperature 1000oC and 1100oC. Characterization of samples was performed using equipment of X-Ray Diffractometer (XRD) to determine the level of crystal form and crystal size of the sample. The more of the Sr composition causes the crystal size is getting larger and lattice parameter getting smaller. Morphology BaxSr1-xTiO3 and Strontium Titanate was tested with instruments of Scanning Electron Microscopy (SEM), a growing number of moles of Sr composition causes the crystal grain size became bigger. Sawyer tower circuit was to got a hysteresis curve. The Tests using the equipment of RLC meter is used to determine the dielectric constant, the measurement is done on the frequency range 1 kHz to 100 kHz. The higher the sintering temperature resulting intensity values, the crystal size and crystallinity, and the grain size getting bigger and dielectric constant value be increase. The dielectric constant (K) is the highest in temperature 1100oC with a thickness of 0.004 m, on the mole of SrTiO3 composition is equal 442. Keywords: Barium Strontium Titanate (BST), Strontium Titanate, Solid State Reaction Method, Dielectric Constant

Burnout: syndrome of burning oneself out at work (SBW)

El objetivo de la siguiente revisión de la literatura es presentar una aproximación sobre el concepto de Burnout o Síndrome de Quemarse en el Trabajo (SQT) remontándose en primera instancia a las teorías del estrés y las estrategias de afrontamiento hasta llegar al concepto del estrés laboral que da curso al surgimiento del Burnout como proceso . Por consiguiente se hace mención de las dimensiones que lo componen, como de la sintomatología física, emocional y conductual que se manifiesta en quienes padecen de este síndrome y las características organizacionales que pueden propiciarlo. Por último, se hace mención de algunos estudios sobre burnout en Colombia y los procesos de intervención respectivos.The aim of the following review of the literature is to present an approach to the concept of Burnout or Burnout Syndrome. In the first instance, it goes back to the theories of stress and coping strategies and arrives at the concept of stress at work which in turn makes way to the emergence of Burnout as process . Consequently, the dimensions that constitute this concept are mentioned along with the physical, emotional and behavioral symptoms present in those who suffer from this syndrome, as well as the organizational characteristics that can cause it. Lastly, some research studies carried in Colombia about Burnout and the respective intervention processes are also mentioned

Sucrose-specific induction of the anthocyanin biosynthetic pathway in Arabidopsis thaliana.

Sugars act as signaling molecules, whose signal transduction pathways may lead to the activation or inactivation of gene expression. Whole-genome transcript profiling reveals that the flavonoid and anthocyanin biosynthetic pathways are strongly up-regulated following sucrose (Suc) treatment. Besides mRNA accumulation, Suc affects both flavonoid and anthocyanin contents. We investigated the effects of sugars (Suc, glucose, and fructose) on genes coding for flavonoid and anthocyanin biosynthetic enzymes in Arabidopsis (Arabidopsis thaliana). The results indicate that the sugar-dependent up-regulation of the anthocyanin synthesis pathway is Suc specific. An altered induction of several anthocyanin biosynthetic genes, consistent with in vivo sugar modulation of mRNA accumulation, is observed in the phosphoglucomutase Arabidopsis mutant accumulating high levels of soluble sugars

Loss of Renal Function After Retrograde Ureteral Placement of an Allium Stent for Severe Ureteral Stricture

Background: Ureteral strictures are a recurrent chronic condition that leads to severe side effects and poor quality of life. Management of ureteral stricture is a great challenge for urologists and no specific guidelines exist. Retrograde Allium®ureteral stent (AUS) is a newly developed ureteral stent to treat either bulbar urethral or ureteral stenosis. Case Presentation: We describe a case of a 74-year-old Caucasian adult male presenting with a severe ureteral stricture secondary to an ureteroscopy for stone disease. Treatment with retrograde AUS placement produced a complete loss of renal function after 36 months, probably because of the development of a long achalasic stretch of the ureter. Conclusions: AUS is a new and promising device for the treatment of ureteral stenosis. However, a lack of standardization of the technique recommends a close instrumental follow-up after the procedure to decide the optimal time for stent removal