Electric field effect on the luminescence of KI:Tl

Thermoluminescence of KI:Tl, x- or &#946;-irradiated at T<77°K showed 2 main peaks at 105 and 170°K. They are resp. attributed to the recombination of mobile VK centers with Tl0 centers and to the recombination of thermally released electrons from Tl0 centers with Tl2+ centres. Similar experiments performed under static electric fields (E<40 kV cm-1) show that the intensity of the 2nd glow peak is strongly reduced. The relative intensity variation is anticorrelated with the intensity of glow peaks occurring at >230°K. We suggestthat in the temperature range in which Tl0 centres are thermally ionised, the effect of the electric field favour the retrapping of these electrons on other traps (still unknown). Irradiation doses also play an important role and their effects are studied at 77°K and T=200°K

A Thalamic Reticular Circuit for Head Direction Cell Tuning and Spatial Navigation.

As we navigate in space, external landmarks and internal information guide our movement. Circuit and synaptic mechanisms that integrate these cues with head-direction (HD) signals remain, however, unclear. We identify an excitatory synaptic projection from the presubiculum (PreS) and the multisensory-associative retrosplenial cortex (RSC) to the anterodorsal thalamic reticular nucleus (TRN), so far classically implied in gating sensory information flow. In vitro, projections to TRN involve AMPA/NMDA-type glutamate receptors that initiate TRN cell burst discharge and feedforward inhibition of anterior thalamic nuclei. In vivo, chemogenetic anterodorsal TRN inhibition modulates PreS/RSC-induced anterior thalamic firing dynamics, broadens the tuning of thalamic HD cells, and leads to preferential use of allo- over egocentric search strategies in the Morris water maze. TRN-dependent thalamic inhibition is thus an integral part of limbic navigational circuits wherein it coordinates external sensory and internal HD signals to regulate the choice of search strategies during spatial navigation

Electric field effect on the luminescence of KI:Tl

Thermoluminescence of KI:Tl, x- or &#946;-irradiated at T230°K. We suggestthat in the temperature range in which Tl0 centres are thermally ionised, the effect of the electric field favour the retrapping of these electrons on other traps (still unknown). Irradiation doses also play an important role and their effects are studied at 77°K and T=200°K

Antidoping programme and biological monitoring before and during the 2014 FIFA World Cup Brazil.

BACKGROUND: The FIFA has implemented an important antidoping programme for the 2014 FIFA World Cup. AIM: To perform the analyses before and during the World Cup with biological monitoring of blood and urine samples. METHODS: All qualified players from the 32 teams participating in the World Cup were tested out-of-competition. During the World Cup, 2-8 players per match were tested. Over 1000 samples were collected in total and analysed in the WADA accredited Laboratory of Lausanne. RESULTS: The quality of the analyses was at the required level as described in the WADA technical documents. The urinary steroid profiles of the players were stable and consistent with previously published papers on football players. During the competition, amphetamine was detected in a sample collected on a player who had a therapeutic use exemption for attention deficit hyperactivity disorder. The blood passport data showed no significant difference in haemoglobin values between out-of-competition and postmatch samples. CONCLUSIONS: Logistical issues linked to biological samples collection, and the overseas shipment during the World Cup did not impair the quality of the analyses, especially when used as the biological passport of football players

Estado, escolas e famílias: públicos escolares e regulação da educação

O texto apresenta alguns resultados de uma investigação recentemente concluída que, genericamente, se inscreve nos complexos processos de (multi)regulação da educação. O estudo desenvolveu-se num concelho do norte de Portugal (convencionalmente designado Vila Formosa), circunscrevendo-se às escolas com oferta de ensino secundário. A análise dos dados sugere que, na topografia complexa dos processos de (multi)regulação do campo escolar, a combinação de medidas de política educativa com recursos e cursos de acção que as diferentes escolas e as diversas categorias de famílias e jovens detêm e adoptam constituem uma tríade de fontes de dinâmicas, umas vezes convergentes, outras vezes em tensão que, por seus efeitos sociológicos cumulativos, geram a reordenação do campo de lutas concorrenciais em torno da educação, lutas essas que parecem penalizar sobretudo as famílias que já sofrem de outras desvantagens.The text presents some results of a recently concluded investigation that, generically, is part of the complex processes of the (multi) regulation of education. The study was developed in a district in the north of Portugal (conventionally designated Vila Formosa) and was limited to schools that offered secondary education. The analysis of the data suggests that, in the complex topography of the processes of (multi)regulation of the school field, the combination of measures of educational policy with resources and courses of action that the different schools and the diverse categories of families and young people possess and adopt constitute a triad of dynamic sources, sometimes convergent and sometimes tense, that, by their cumulative sociological effects, generate the re-ordination of the field of competing struggles in education that seem to penalize, above all, the families that already suffer other disadvantages.El texto presenta algunos resultados de una investigación recientemente finalizada que, genéricamente, se inscribe en los complexos procesos de (multi) regulación de la educación. El estudio se desarrolló en un consejo del norte de Portugal (asignado convencionalmente Vila Formosa), circunscribiéndose a las escuelas con oferta de enseñanza secundaria. El análisis de los datos sugiere que, en la compleja topografía de los procesos de (multi)regulación del campo escolar, la combinación de medidas de política educativa con los recursos y los cursos de acción que las diferentes escuelas y las diversas categorías de familias y jóvenes retienen y que adoptan, constituyen una tríada de fuentes de dinámicas, unas veces convergentes, otras veces en tensión que, por sus efectos sociológicos acumulativos, generan la reordenación del campo de luchas competitivas alrededor de la educación y de los resultados de esas luchas que parecen penalizar principalmente a las familias que ya sufren de otras desventajas.(undefined

Fluorescent nanopigments: Quantitative assessment of their quantum yield

In the last few years, an intense research effort has focused on the synthesis of fluorescent nanopigments for functional inks, light harvesting, tagging, tracing, (bio)labeling, imaging, and lighting applications. Moreover, combined with dielectric matrices, these fluorescent nanoparticles may open the way to the realization of novel optophotonic devices. In particular, due to the large variety of available organic fluorescent dyes, their encapsulation into either an inorganic or an organic host is a very promising approach to synthesize a large palette of new fluorescent nanopigments. However, since the dye encapsulation may affect the fluorescence efficiency, measuring the quantum yield of fluorescent nanopigments is of paramount importance for the development of any connected application. In this article, we present a diffuse reflectance (DR) technique that enables the quantitative assessment of the quantum yield of fluorescent nanoparticles such as zeolite L nanocrystals and poly(methyl methacrylate) nanospheres both loaded with fluorescent perylene molecules. Our method is validated by measuring a well known fluorescence standard and by comparing the results obtained for a model zeolite nanopigment with those provided by an alternative DR technique. Reliable and reproducible quantum yield values are obtained for both low- and high-efficiency fluorescent nanoparticles. Our technique can thus enable systematic and quantitative studies that may yield an important insight in the mechanisms affecting the fluorescence efficiency of a large variety of nanopigments

Cuidado de enfermagem para enfermeiros docentes na perspectiva da complexidade

O cuidado de enfermagem complexo é condição essencial para a compreensão do ser humano como singular e multidimensional. Assim, objetivou-se conhecer o significado do cuidado de enfermagem para enfermeiros docentes, na perspectiva da complexidade. Trata-se de uma pesquisa qualitativa, realizada com sete enfermeiros docentes deum curso de enfermagem de nível superior da região central do Rio Grande do Sul, Brasil. Os dados foram coletados no mês de novembro de 2011, por meio do grupo focal, a partir de três encontros, sistematizados com temáticas que contemplassem o objetivo deste estudo. Para a análise de dados, foi utilizada a análise textual discursiva. Os resultados evidenciaram o cuidado de enfermagem como construção singular que vai além de um cuidado técnico-prescritivo, pontual e linear. Conclui-se que o cuidado de enfermagem não pode ser concebido como açãoreducionista, mas como construção singular, que envolve interações, reflexões e autoconhecimento

Increased Hydrogen Production by Genetic Engineering of Escherichia coli

Escherichia coli is capable of producing hydrogen under anaerobic growth conditions. Formate is converted to hydrogen in the fermenting cell by the formate hydrogenlyase enzyme system. The specific hydrogen yield from glucose was improved by the modification of transcriptional regulators and metabolic enzymes involved in the dissimilation of pyruvate and formate. The engineered E. coli strains ZF1 (ΔfocA; disrupted in a formate transporter gene) and ZF3 (ΔnarL; disrupted in a global transcriptional regulator gene) produced 14.9, and 14.4 µmols of hydrogen/mg of dry cell weight, respectively, compared to 9.8 µmols of hydrogen/mg of dry cell weight generated by wild-type E. coli strain W3110. The molar yield of hydrogen for strain ZF3 was 0.96 mols of hydrogen/mol of glucose, compared to 0.54 mols of hydrogen/mol of glucose for the wild-type E. coli strain. The expression of the global transcriptional regulator protein FNR at levels above natural abundance had a synergistic effect on increasing the hydrogen yield in the ΔfocA genetic background. The modification of global transcriptional regulators to modulate the expression of multiple operons required for the biosynthesis of formate hydrogenlyase represents a practical approach to improve hydrogen production