Spin-polarized tunneling spectroscopy in tunnel junctions with half-metallic electrodes

We have studied the magnetoresistance (TMR) of tunnel junctions with electrodes of La2/3Sr1/3MnO3 and we show how the variation of the conductance and TMR with the bias voltage can be exploited to obtain a precise information on the spin and energy dependence of the density of states. Our analysis leads to a quantitative description of the band structure of La2/3Sr1/3MnO3 and allows the determination of the gap delta between the Fermi level and the bottom of the t2g minority spin band, in good agreement with data from spin-polarized inverse photoemission experiments. This shows the potential of magnetic tunnel junctions with half-metallic electrodes for spin-resolved spectroscopic studies.Comment: To appear in Physical Review Letter

Les formes d’infection de la mamelle de la Vache

Jacquet Jean, Julienne Pierre. Les formes d’infection de la mamelle de la Vache. In: Bulletin de l'Académie Vétérinaire de France tome 104 n°8, 1951. pp. 423-428

Recherches sur la production de toxine par Aspergillus flavus

Boutibonnes Ph., Jacquet Jean. Recherches sur la production de toxine par Aspergillus flavus. In: Bulletin de l'Académie Vétérinaire de France tome 120 n°8, 1967. pp. 393-403

Recherches sur les caractères des Aspergillus pathogènes. Les espèces mineures

Jacquet Jean, Boutibonnes Ph. Recherches sur les caractères des Aspergillus pathogènes. Les espèces mineures. In: Bulletin de l'Académie Vétérinaire de France tome 120 n°10, 1967. pp. 489-500

Nouvelles recherches sur les effets des flavacoumarines (aflatoxines) sur les animaux

Jacquet Jean, Boutibonnes Ph. Nouvelles recherches sur les effets des flavacoumarines (aflatoxines) sur les animaux. In: Bulletin de l'Académie Vétérinaire de France tome 124 n°1, 1971. pp. 65-72

Influence of anthropometric parameters and biochemical markers of bone metabolism on quantitative ultrasound of bone in the institutionalized elderly

The assessment of bone quality by quantitative ultrasound (QUS), a transportable and relatively cheap method, shows some correlations with bone mineral density (BMD) as measured by dual-energy X-ray absorptiometry (DXA) and with fracture risk. To examine its correlation with bone metabolism in a population of institutionalized elderly people known to be at high risk for vitamin D deficiency and secondary hyperparathyroidism, QUS of the calcaneus and biochemical parameters were measured in 264 women aged 85±7 (SD) years and in 103 men aged 81±8 years living in 19 nursing homes. Vitamin D deficiency was frequent in this population: 41.9% of the women and 31.4% of the men had a serum 25-hydroxyvitamin (25OHD) level below the 2.5th percentile level of 3276 normal Swiss adults (6.2 µg/l or 15.5 mmol/l). Hyperparathyroidism was less frequent: serum parathyroid hormone (PTH) levels were above the 97.5th percentile level of normal adults (70 pg/l) in 18.9% of women and 9.8% of men. In women, QUS data correlated significantly with age (r=−0.297), body mass index (BMI) (r=0.403), calcium (r=0.220), PTH (r=−0.296), 25OHD (r=0.298) and alkaline phosphatase (AP) (r=−0.170) for broadband ultrasound attenuation (BUA), and with age (r=−0.195), BMI (r=0.208), PTH (r=−0.174), 25OHD (r=0.140) and AP (r=−0.130) for speed of sound (SOS). In men, ultrasound data correlated with BMI (r=0.326), calcium (r=0.199), 25OHD (r=0.258) and AP (r=−0.311) for BUA, and with AP (r=−0.196) for SOS. In women, but not in men because of their smaller number, a multivariate analysis was performed to examine relationships between age, BMI, biochemical markers and QUS. Age, BMI, PTH and phosphate explained 30% of the variance of BUA and 10% for SOS. In conclusion, QUS of bone evaluates characteristics of bone that are influenced, at least partially, by age, BMI and the secondary hyperparathyroidism due to vitamin D deficienc

Observations sur la toxicité d’ Aspergillus clavatus pour les animaux

Jacquet Jean, Boutibonnes Ph., Cicile J.-P. Observations sur la toxicité d'Aspergillus clavatus pour les animaux. In: Bulletin de l'Académie Vétérinaire de France tome 116 n°4, 1963. pp. 199-208