Imprints of Dark Energy on Cosmic Structure Formation I) Realistic Quintessence Models and the Non-Linear Matter Power Spectrum

Dark energy as a quintessence component causes a typical modification of the background cosmic expansion, which in addition to its clustering properties, can leave a potentially distinctive signature on large scale structures. Many previous studies have investigated this topic, particularly in relation to the non-linear regime of structure formation. However, no careful pre-selection of viable quintessence models with high precision cosmological data was performed. Here we show that this has led to a misinterpretation (and underestimation) of the imprint of quintessence on the distribution of large scale structures. To this purpose we perform a likelihood analysis of the combined Supernova Ia UNION dataset and WMAP5-years data to identify realistic quintessence models. Differences from the vanilla LambdaCDM are especially manifest in the predicted amplitude and shape of the linear matter power spectrum, though these remain within the uncertainties of the SDSS data. We use these models as benchmark for studying the clustering properties of dark matter halos by performing a series of high resolution N-body simulations. We find that realistic quintessence models allow for relevant differences of the dark matter distribution with the respect to the LambdaCDM scenario well into the non-linear regime, with deviations up to 40% in the non-linear power spectrum. Such differences are shown to depend on the nature of DE, as well as the scale and epoch considered. At small scales (k~1-5 h Mpc^{-1}, depending on the redshift) the structure formation process is about 20% more efficient than in LambdaCDM. We show that these imprints are a specific record of the cosmic structure formation history in DE cosmologies and therefore cannot be accounted in standard fitting functions of the non-linear matter power spectrum.Comment: 24 pages, 11 figures. Higher resolution paper available at http://cp3.phys.ucl.ac.be/upload/papers/astro-ph-0903.5490.ps (ps) and http://cp3.phys.ucl.ac.be/upload/papers/astro-ph-0903.5490.pdf (pdf). v2: New discussion on the non-linear power spectrum at small scales. v3: same as v2 with corrected references. Matches version to appear in MNRA

Multifaceted roles of GSK-3 and Wnt/β-catenin in hematopoiesis and leukemogenesis: opportunities for therapeutic intervention

Glycogen synthase kinase-3 (GSK-3) is well documented to participate in a complex array of critical cellular processes. It was initially identified in rat skeletal muscle as a serine/threonine kinase that phosphorylated and inactivated glycogen synthase. This versatile protein is involved in numerous signaling pathways that influence metabolism, embryogenesis, differentiation, migration, cell cycle progression and survival. Recently, GSK-3 has been implicated in leukemia stem cell pathophysiology and may be an appropriate target for its eradication. In this review, we will discuss the roles that GSK-3 plays in hematopoiesis and leukemogenesis as how this pivotal kinase can interact with multiple signaling pathways such as: Wnt/β-catenin, phosphoinositide 3-kinase (PI3K)/phosphatase and tensin homolog (PTEN)/Akt/mammalian target of rapamycin (mTOR), Ras/Raf/MEK/extracellular signal-regulated kinase (ERK), Notch and others. Moreover, we will discuss how targeting GSK-3 and these other pathways can improve leukemia therapy and may overcome therapeutic resistance. In summary, GSK-3 is a crucial regulatory kinase interacting with multiple pathways to control various physiological processes, as well as leukemia stem cells, leukemia progression and therapeutic resistance. GSK-3 and Wnt are clearly intriguing therapeutic targets

A Robotic Platform for Neurointervention

Neurointerventional procedures involve a guidewire and a system of catheters that are maneuvered through the circulatory system into the brain. Due to the procedure's precise nature, X-rays enable practitioners to see the catheter inside the patient, leaving them vulnerable to excess radiation even with protective lead clothing. This paper explores the development of a proof-of-concept prototype for remotely controlling modularized telescoping catheters ensuring rotational and linear accuracy and compatibility with various catheter sizes. Several prototypes were developed, systematically refining the model through testing and further literature research. While improved manufacturing techniques and electronics would be required to get the necessary precision, the final iteration showed that this concept for telescoping catheter control is viable. Recommendations for future work are discussed, and this project serves as a strong starting point for future endeavors that will lead to improvements in the field of robotic neurointervention

Reabilitação de pacientes portadores da doença de Kienböck submetidos a ressecção da fileira proximal do carpo Rehabilitation of patients with Kienböck disease underwent proximal row carpectomy

A proposta deste estudo foi a aplicação de um protocolo de avaliação e tratamento desenvolvido no Serviço de Terapia da Mão do Setor de Terapia Ocupacional da Disciplina de Fisiatria do Departamento de Ortopedia e Traumatologia da Universidade Federal de São Paulo, destinado a pacientes portadores da Doença de Kienböck e submetidos a técnica cirúrgica de ressecção da fileira proximal do carpo. O protocolo de avaliação foi aplicado em 16 pacientes que foram avaliados no pré e pós-tratamento, considerando-se a dor, perímetro do punho, força muscular, amplitude articular do antebraço e punho e a capacidade funcional. Considerou-se também alguns referenciais subjetivos, no que se refere à satisfação pessoal do paciente quanto ao tratamento. Os resultados mostraram que o protocolo de tratamento aplicado foi eficaz na redução da dor, no aumento do arco de movimento da pronação e supinação do antebraço, abdução e adução do punho e favoreceu a melhora da capacidade funcional da mão afetada. Na avaliação subjetiva 90% dos pacientes tratados em nosso protocolo estavam satisfeitos com a sua recuperação.<br>The aim of this study was to apply an evaluation and treatment protocol developed by the Hand Therapy Department of the Occupational Therapy Group of Physiatrics Medicine, Department of Orthopedics and Traumatology, University of São Paulo, to patients with Kienböck disease underwent proximal row carpectomy. The protocol was applied to 16 patients who were assessed in the pretreatment and post-treatment periods concerning some objective parameters, such as pain, wrist circumference, muscular strength, forearm / wrist articular range of motion and functional capacity. Patients' satisfaction with their evolution was evaluated through a questionnaire according to the treatment. Results have shown that the group underwent a rehabilitation approach showed better outcomes concerning pain, muscle strength, supination, abduction and adduction range of motion and an improved hand functional efficacy. Subjective evaluation showed 90% satisfaction in the rehabilitation group