Optimal Control Systems with Constrains Defined on Unbounded Sets

Non

El camino de la fe hacia la confianza en Faustina Kowalska

Entre muchas expresiones de la piedad popular un lugar destacado lo ocupa la devoción a la divina misericordia. El objetivo central de la devoción es suscitar y afianzar en el creyente la confianza en la misericordia divina. Santa Faustina Kowalska documentó en su diario espiritual su propio camino de fe hacia la confianza. Su experiencia de fe es un lugar teológico donde se buscan unas pistas que ayuden al creyente desarrollar y afianzar la virtud de la confianza. El método del circulo hermenéutico, articuló diferentes elementos del presente trabajo investigativo y lo organizó en tres capítulos. El primero corresponde al horizonte teológico del autor donde se analiza diferentes significados de la experiencia de Dios. El segundo capítulo cosiste en el análisis de la vida y del diario espiritual de sor Faustina Kowalska. El tercer capítulo corresponde al momento de la fusión de los dos horizontes y a la interpretación en la que a partir del resultado arrojado por la investigación se plantean unas líneas para el desarrollo y afianzamiento de la confianza.Among many expressions of popular piety a prominent place is devotion to divine mercy. The central aim of devotion is to arouse and strengthen in the believer the confidence in the divine mercy. St. Faustina Kowalska documented in her spiritual diary her own path of faith toward trust. Their experience of faith is a theological place where they are looking for clues that help the believer develop and strengthen the virtue of trust. The hermeneutic circle method articulated different elements of the present research work and organized it into three chapters. The first corresponds to the theological horizon of the author where we analyze different meanings of the experience of God. The second chapter consists in the analysis of the life and spiritual diary of Sister Faustina Kowalska. The third chapter corresponds to the moment of the fusion of the two horizons and to the interpretation in which, starting from the result of the research, some lines of development for confidence building are established.Magíster en TeologíaMaestrí

The path to the “ideal” brain PET imager: The race is on, the role for TOF PET

With the efforts under way to improve spatial resolution of the revolutionary Explorer family of imagers, the acute need to develop dedicated imagers for breast, prostate, heart, etc. may slowly disappear, except for some specialized cases in treatment guidance and monitoring, for example in proton therapy. It is in fact happening already. Part of the reason is the high cost of the dedicated systems but also an intriguing emerging opportunity that long axial length PET scanners can be equipped with magnifying inserts that can locally boost the resolution, as per the so-called virtual pinhole concept by Yuan-Chuan Tai from WashU, also called Zoom-in PET. However, the exception are the brain imaging scanners. The special geometry of the optimal helmet type designs for imaging of the brain still gives the opportunity to the brain PET imager developers to compete for the “best” system. We all want to produce good quality dynamic molecular PET brain images at low injected radiation doses (and... low cost). Several designs are being proposed as well as being built at this time in many places around the world. These designs mostly fall in two categories: 1) the mini-Explorer cylindrical type or 2) the compact helmet type, both with large angular brain coverage assuring high sensitivity. Due to the compact sizes of the helmet-type systems, in order to substantially benefit from the improved TOF performance, one needs to achieve better than 100 ps FWHM timing performance. In fact, 50 ps FWHM would be a very nice goal. Several groups are working on such concepts. In this race, any new ideas from the expert instrumentation community (not only the medical one) are highly encouraged, as a great impact is expected on brain imaging once such high-performance but also dissemination-ready (i.e., robust and economical) designs are developed. Ideally, the brain imagers of the next generation will have high sensitivity and high spatial resolution approaching the predicted physical limit (due to positron range plus non-collinearity of the two emitted annihilation photons), limited to about 1 mm FWHM. Interestingly, there is a known connection between spatial resolution and sensitivity in detecting small lesions or structures, through the Partial Volume Effect (PVE). The adversarial effect of poor resolution on the detection of small structures is the blurring of the signal with the background. Inversely, if there is not enough statistics (detected/recorded events) per reconstruction voxel, even the best spatial resolution will not bring the tomographic uptake signal above the noisy background

Imaging is believing: The future of human total-body molecular imaging starts now

Explorer brings revolution to medical imaging. The wealth of molecular/functional information provided by a single scan is overwhelming. Beyond the obvious issues of how to store and analyze this vast amount of data, and how to fuse the PET images from the almost 200 cm long total-body PET imager with MRI images, the imaging scientists work on improving spatiotemporal resolution of the scanner. But how can we obtain better spatial and time (time of flight) resolutions at the same time? Efforts to push timing resolution down to 50 ps and potentially even down to 10 ps were initiated. While attaining ∼ 1 mm resolution in the totalbody Explorer imager is not immediately practically possible or even justifiable, due to other limiting factors such as large amount of recorded coincident events (“statistics”) necessary to produce good quality ∼ 1 mm resolution images in the human body and not just as before in the small animal body, one of the high-resolution scenarios is to imagine and start planning magnifying attachments-inserts to the Explorer scanner and a dedicated very high-performing (∼ 1 mm resolution, 100 ps or better TOF resolution and ∼30% efficiency) compact brain imager. This (Explorer + Brain) Tandem PET scanner may be closer to the ideal optimal human PET imager, if there is small interference between the two imager components to image body and brain, respectively. Other options such as 100 cm long extended Torso Explorer plus Brain Imager are also being discussed

Development of a novel, high-affinity ssDNA trypsin inhibitor

Inhibitors of serine proteases are not only extremely useful in the basic research but are also applied extensively in clinical settings. Using Systematic Evolution of Ligands by Exponential Enrichment (SELEX) approach we developed a family of novel, single-stranded DNA aptamers capable of specific trypsin inhibition. Our most potent candidate (T24) and its short version (T59) were thoroughly characterised in terms of efficacy. T24 and T59 efficiently inhibited bovine trypsin with Ki of 176 nM and 475 nM, respectively. Interestingly, in contrast to the majority of known trypsin inhibitors, the selected aptamers have superior specificity and did not interact with porcine trypsin or any human proteases tested. These included plasmin and thrombin characterised by trypsin-like substrate specificity. Our results demonstrate that SELEX may be successfully employed in the development of potent and specific DNA based protease inhibitors