Somatostatin binding sites have been localized and quantified in the sheep brain using 125I-Tyr0-DTrp8-somatostatin, by quantitative high resolution light microscopic autoradiography. Sections were ...analyzed by densitometry on radioautographic film, and subsequently on slides coated with photoemulsion. Specific somatostatin binding sites were concentrated in the medial habenula, superior colliculus, dorsal motor nucleus of the vagus nerve, inferior olive, spinal trigeminal nucleus, and cerebellum. In competition experiments, octreotide, a sst2/sst3/sst5 selective agonist only partially displaced 125I-Tyr0-DTrp8-somatostatin in the three cerebellar layers while it was fully active as compared to somatostatin 14 and 28 in the deeper layers of the parietal cortex. Moderate to low somatostatin receptor densities were present in the mesencephalic periaqueductal gray, dorsal raphe, thalamic paraventricular nucleus, interpeduncular nucleus, pineal gland, dorsal tegmental, dorsolateral tegmental and parabrachial nuclei, nucleus of the solitary tract. The distribution of somatostatin binding sites generally correlates with the data obtained on slides dipped in photoemulsion which provided better resolution and more precise localization. In most of the labeled areas, 125I-Tyr0-DTrp8-somatostatin receptor binding was distributed between both neuropil and perikarya. Perikarya bearing 125I-Tyr0-DTrp8-somatostatin receptors were observed in areas which did not display detectable binding sites on film such as the preoptic-anterior hypothalamic complex and arcuate nucleus and in the locus coeruleus. In conclusion, the distribution of 125I-Tyr0-DTrp8-somatostatin binding sites in sheep brain is very reminiscent of other mammals being closer to the human than to rodents.
Data taken with the ALEPH detector at LEP1 have been used to search for
γγ production of the glueball candidates
f
0(1500) and
f
J
(1710) via their decay to
π
+
π
−. No signal is observed and upper ...limits to the product of
γγ width and
π
+
π
− branching ratio of the
f
0(1500) and the
f
J
(1710) have been measured to be
Γ(γγ→f
0(1500))·
B
R(f
0(1500)→π
+π
−)<0.31
keV
and
Γ(γγ→f
J(1710))·
B
R(f
J(1710)→π
+π
−)<0.55
keV
at 95% confidence level.
We measure the emission of energetic electrons from the interaction between ultrashort laser pulses and a solid density plasma in the relativistic regime. We detect an electron beam that only appears ...with few-cycle pulses (< 10 fs) and large plasma scale lengths (\(L > \lambda_0\)). Numerical simulations, in agreement with the experiments, reveal that these electrons are accelerated by a laser wakefield. Plasma waves are indeed resonantly excited by the few-cycle laser pulses in the near-critical-density region of the plasma. Electrons are then injected by ionization into the plasma waves and accelerated to relativistic energies. This study provides an unprecedented insight into the physics happening in the few-cycle regime.
The analysis of "professional motivations", mainly through the possible crowding-out effects between extrinsic and intrinsic motivations, has become an issue of great concern in the economic ...literature. This paper aims at applying this topic to the healthcare professions where the proper scaling up of pay-for-performance (P4P) policies by public authorities is at stake.
We used a panel of 528 self-employed general practitioners in the "Provence-Alpes-Côte d'Azur" region in France to provide an interpersonal statistical decomposition between extrinsic and intrinsic motivations with regard to preventive actions. Then, we applied a Tobit model in order to specify the main explicative variables of the share of intrinsic motivations entering into physicians' total motivations.
The relative share of intrinsic motivations was quite high among physicians paid with fixed fees. We found a significant effect of age on intrinsic motivations describing a U-shaped curve which can be interpreted as being the result of a "life cycle of medical motivations" or a generational effect.
The cross-sectional nature of the data does not allow us to draw any conclusions concerning the predominance of the generational effect or the "life cycle effect" on the evolution of the relative share of physician's intrinsic motivations. Nevertheless, the U-shaped relation between intrinsic motivations and age questions the suitability of using uniformly P4P mechanisms. The generations or age groups of self-employed physicians who seem to be less responsive to extrinsic motivations are more likely to favour the introduction of other types of payment schemes (capitation or salary systems) or regulation tools such as clinical practice guidelines.
Data taken with the ALEPH detector at LEP1 have been used to search for gamma gamma production of the glueball candidates f0(1500) and fJ(1710) via their decay to pi+pi-. No signal is observed and ...upper limits to the product of gamma gamma width and pi+pi- branching ratio of the f0(1500) and the fJ(1710) have been measured to be Gamma_(gamma gamma -> f0(1500)). BR(f0(1500)->pi+pi-) 0.31 keV and Gamma_(gamma gamma -> fJ(1710)). BR(fJ(1710)->pi+pi-) 0.55 keV at 95\-onfidence level.
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