Convective Motion in a Vibrated Granular Layer

Experimental results are presented for a vertically shaken granular layer. In the range of accelerations explored, the layer develops a convective motion in the form of one or more rolls. The velocity of the grains near the wall has been measured. It grows linearly with the acceleration, then the growing rate slows down. A rescaling with the amplitude of the wall velocity and the height of the granular layer makes all data collapse in a single curve. This can provide insights on the mechanism driving the motion.Comment: 10 pages, 5 figures submitted to Phys. Rev. Let

Safety assessment of essential medicines for elderly people: a bibliographic survey

Certain medicines are considered potentially inappropriate (PIM) for elderly people as they increase the risk of adverse drug events (ADE) and because safer alternative therapies are available on the market. In this context, in order to identify the instruments that assess the quality of medical prescriptions for elderly and to determine which drugs are considered PIM, a bibliographic survey was conducted in PUBMED, LILACS and PAHO databases, in February and March/2010. The search strategy included the use of health descriptors and a manual search in the references cited by selected papers. During the period of data collection, 15 instruments were identified. In 2012, with the publication of the update of Beers criteria, this instrument was included in the study. We identified 163 PIM of 25 therapeutic classes, of which 125 (76.7%) are marketed in Brazil. Of these, 31 (24.8%) are essential medicines (RENAME 2012), of which 13 have safer therapeutic equivalents and 19 (15.2%) are over-the-counter drugs. Data suggest the need for inclusion of safer alternatives for the elderly in the national list of essential medicines and the pharmaceutical care for early detection of ADE in this age group, in order to contribute to the safe use of medicines

Increase in [3H]glutamate release from slices of dentate gyrus and hippocampus following classical conditioning in the rat

International audienceThe release of amino acids was examined in three hippocampal areas following classical conditioning. Paired or unpaired tone(CS)-shock(US) presentations were given to animals engaged in a previously acquired food-motivated lever-pressing task. Conditioned suppression of lever-pressing was the behavioural measure of conditioning. The dentate gyrus and areas CA1 and CA3 of the hippocampus were removed bilaterally from conditioned and pseudoconditioned animals, and slices cut and stored in liquid nitrogen for subsequent in vitro analysis of the release of radiolabelled glutamate and aspartate. K+-stimulated release of radiolabelled amino acids was analysed in the presence and absence of extracellular Ca2+. Potassium-stimulated, Ca2+-dependent release of [3H]glutamate was significantly greater in slices of dentate gyrus and area CA1 prepared from conditioned animals than from pseudoconditioned animals. This finding identifies a neurochemical change associated with classical conditioning which is similar to the increase in transmitter release seen in hippocampal long-term potentiation (LTP), and which is consistent with the hypothesis that an LTP-like mechanism is involved in mnemonic processes

Increase in K+-stimulated, Ca2+-dependent release of [3H]glutamate from rat dentate gyrus three days after induction of long-term potentiation

International audienceLong-term potentiation (LTP) was induced by unilateral tetanic stimulation of the perforant path in the dentate gyrus of rats with implanted electrodes. Evoked potentials were monitored for the subsequent 3 days in one group, and for 23 days in another. The dentate gyrus was removed bilaterally and slices prepared and stored in 10% DMSO/Krebs for subsequent analysis of K+-stimulated, Ca2+-dependent release of [3H]glutamate. In the 3-day group, in which the mean increase in the population EPSP was 35% at the time of sacrifice, release from the tetanized side was significantly greater than from the unstimulated side. In the 23-day group, both the increase in the EPSP and the increase in release from the tetanized side had declined to statistically insignificant levels. These results extend to a period of several days the previously observed association between LTP and increased K+-stimulated, Ca2+-dependent release of transmitter

Attitudes and beliefs of older adults and caregivers towards deprescribing in French-speaking countries: a multicenter cross-sectional study.

Successful deprescribing requires understanding the attitudes of older adults and caregivers towards this process. This study aimed to capture these attitudes in four French-speaking countries and to investigate associated factors. A multicenter cross-sectional study was conducted by administrating the French version of the revised Patients' Attitudes Towards Deprescribing (rPATD) questionnaire in Belgium, Canada, France, and Switzerland. Community-dwelling or nursing home older adults ≥ 65 years taking ≥ 1 prescribed medications and caregivers of older adults with similar characteristics were included. Multivariate logistic regressions were carried out to examine factors associated with willingness to deprescribe. A total of 367 older adults (79.3 ± 8.7 years, 63% community-dwelling, 54% ≥ 5 medications) and 255 unrelated caregivers (64.4 ± 12.6 years) of care recipients (83.4 ± 7.9 years, 52% community-dwelling, 69% ≥ 5 medications) answered the questionnaire. Among them, 87.5% older adults and 75.6% caregivers would be willing to stop medications if the physician said it was possible. Reluctance to stop a medication taken for a long time was expressed by 46% of both older adults and caregivers. A low score for the factor "concerns about stopping" (older adults: aOR: 0.21; 95% CI: 0.07-0.59), and a high score for the factor "involvement" (older adults: aOR: 2.66; 95% CI: 1.01-7.07; caregivers: aOR: 11.28; 95% CI: 1.48-85.91) were associated with willingness to deprescribe. A significant proportion of older adults and caregivers of French-speaking countries are open to deprescribing. Despite this apparent willingness, deprescribing conversations in clinical practice remains marginal, emphasizing the importance of optimizing the integration of existing tools such as rPATD