Precision spectroscopy of helium in a magic wavelength optical dipole trap

Improvements in both theory and frequency metrology of few-electron systems such as hydrogen and helium have enabled increasingly sensitive tests of quantum electrodynamics (QED), as well as ever more accurate determinations of fundamental constants and the size of the nucleus. At the same time advances in cooling and trapping of neutral atoms have revolutionized the development of increasingly accurate atomic clocks. Here, we combine these fields to reach the highest precision on an optical tranistion in the helium atom to date by employing a Bose-Einstein condensate confined in a magic wavelength optical dipole trap. The measured transition accurately connects the ortho- and parastates of helium and constitutes a stringent test of QED theory. In addition we test polarizability calculations and ultracold scattering properties of the helium atom. Finally, our measurement probes the size of the nucleus at a level exceeding the projected accuracy of muonic helium measurements currently being performed in the context of the proton radius puzzle

Acoustic analysis of prosody in Sydenham's chorea Análise acústica da prosódia em coréia de Sydenham

There are few studies of language and speech in patients with Sydenham's chorea (SC). We have done an acoustic analysis of fundamental frequency (F0), duration and intensity of declarative and interrogative sentences made by 20 SC patients, 20 patients with rheumatic fever (RF) without chorea, and compared them with 20 healthy age-matched controls (CO). Each group included 12 females. We found that there is no difference between the RF and CO groups in all studied parameters. Patients with SC, however, presented with a speech characterized by decreased F0 range (difference between minimum and maximum F0), shorter duration of sentences, and higher intensity of the first syllable of sentences. The findings were not influenced by the nature of the sentences (i.e. , declarative or interrogative), but for all variables they were significantly more severe in males than females. In conclusion, we have demonstrated that patients with acute SC have an impairment of modulation of F0 and longer duration of emission of sentences, resulting in a monotone and slow speech. This pattern is similar to what has been described in other basal ganglia illnesses, such as Parkinson's disease, Huntington's disease and Wilson's disease.<br>Há poucos estudos sobre linguagem e fala em pacientes com coréia de Sydenham (CS). Fizemos uma análise acústica da freqüência fundamental (F0), duração e intensidade de sentenças declarativas e interrogativas feitas por 20 pacientes com CS, 20 pacientes com febre reumática (FR) sem coréia, comparando-os com 20 controles saudáveis e pareados por idade (CO). Cada grupo incluiu 12 mulheres. Foi encontrado que não há diferença entre os grupos FR e CO quanto a todos parâmetros estudados. Pacientes com CS, contudo, apresentaram-se com fala caracterizada pela redução da variação de F0 (diferença entre F0 mínima e máxima), duração mais curta das sentenças e maior intensidade da primeira sílaba das sentenças. Os achados não foram influenciados pela natureza das sentenças (i.e. , declarativas ou interrogativas), mas os achados foram mais evidentes em todas as variáveis em homens em contraste com mulheres. Em conclusão, demonstramos que pacientes com CS aguda têm prejuízo da modulação da F0 e duração mais longa da emissão de sentenças, resultando em fala mais lenta e monótona. Esse padrão é semelhante ao que tem sido descrito em outras fecções dos núcleos da base, tais como doença de Parkinson, doença de Huntington e doença de Wilson

Taking advantage of tumor cell adaptations to hypoxia for developing new tumor markers and treatment strategies

Cancer cells in hypoxic areas of solid tumors are to a large extent protected against the action of radiation as well as many chemotherapeutic drugs. There are, however, two different aspects of the problem caused by tumor hypoxia when cancer therapy is concerned: One is due to the chemical reactions that molecular oxygen enters intoin therapeutically targeted cells. This results in a direct chemical protection against therapy by the hypoxic microenvironment which has little to do with cellular biological regulatory processes. This part of the protective effect of hypoxia has been known for more than half a century and has been studied extensively. However, in recent years more focus has been put into the other aspect of hypoxia, namely the effect of this microenvironmental condition on selecting cells with certain genetical pre-requisites that are negative with respect to patient prognosis. There are adaptive mechanisms, where hypoxia induces regulatory cascades in cells resulting in a changed metabolism or changes in extra cellular signalling. These processes may lead to changes in cellular intrinsic sensitivity to treatment irrespective of oxygenation and furthermore, may also have consequences for tissue organization. Thus, the adaptive mechanisms induced by hypoxia itself may have a selective effect on cells with a fine-tuned protection against damage and stress of many kinds. It therefore could be that the adaptive mechanisms may be taken advantage of for new tumor labelling/imaging and treatment strategies. One of the Achilles’ heels of hypoxia research has always been exact measurements of tissue oxygenation as well as control of oxygenation in biological tumor models. Thus, development of technology that can ease this control is vital in order to study mechanisms and perform drug development under relevant conditions. An integrated EU Framework project 2004-2009, termed Euroxy, demonstrates several pathways involved in transcription and translation control of the hypoxic cell phenotype and evidence of cross talk with responses to pH and redox changes. The carbon anhydrase isoenzyme CA IX was selected for further studies due to its expression on the surface of many types of hypoxic tumors. The effort has lead to marketable culture flaks with sensors and incubation equipment and the synthesis of new drug candidates against new molecular targets. New labelling/imaging methods for cancer diagnosing and imaging of hypoxic cancer tissue now are being tested in xeno-graft models and also are in early clinical testing while new potential anticancer drugs are undergoing tests using xenografted tumor cancers. The present paper describes the above results in individual consortium partner presentations