The Structure of Barium in the hcp Phase Under High Pressure

Recent experimental results on two hcp phases of barium under high pressure show interesting variation of the lattice parameters. They are here interpreted in terms of electronic structure calculation by using the LMTO method and generalized pseudopotential theory (GPT) with a NFE-TBB approach. In phase II the dramatic drop in c/a is an instability analogous to that in the group II metals but with the transfer of s to d electrons playing a crucial role in Ba. Meanwhile in phase V, the instability decrease a lot due to the core repulsion at very high pressure. PACS numbers: 62.50+p, 61.66Bi, 71.15.Ap, 71.15Hx, 71.15LaComment: 29 pages, 8 figure

Dynamic Autoregressive Liquidity (DArLiQ)

Motivated beliefs theory suggests the absorption of information may be biased, especially when it bears consequences for the ego. This paper finds empirical support for that hypothesis in the field, using longitudinal data on teenagers’ memories of mathematics report card grades and administrative data on actual grades. Students: i) make more errors in recalling lower grades; ii) update their academic self-confidence in association with recalled grades rather than actual grades; and iii) have more flattering memories of grades when the survey was administered with a longer delay. The first two results bolster recent research in demonstrating that patterns of motivated recall are robust to within-individual estimation. The last result extends the field literature in showing that a large part of the mechanism for motivated information absorption is memory loss over time. A structural model is used to represent memories as the outcome of a subconscious choice problem, disentangling competing motives to enhance self-confidence and respect reality. The estimated model indicates that the costs of memory distortions decrease as time passes after information transmission, and students with low self-confidence had a greatly diminished preference for inflating self-confidence via memory distortion

Influence of capture and wing tagging on the little egret (Egretta garzetta) during the breeding season

En Camargue, depuis 4 ans, des aigrettes garzettes adultes sont capturées sur le nid et marquées par plaque alaire. Le succès de reproduction de ces oiseaux a été comparé à celui d'un groupe témoin. Aucune différence n'est significative, quelque soit la phase de nidification considérée. Il n'apparaît pas, non plus, de différences entre la condition corporelle des poussins issus des différents groupes. Les méthodes de capture et de marquage utilisées peuvent donc être considérées comme efficaces et sûre

The effects of winter climate on the size of the cattle egret (Bubulcus ibis L.) population in the Camargue

La population nicheuse de Hérons gardebœufs de Camargue a été suivie de 1970 à 1991. Chaque année, 60 à 70 % des oiseaux présents en fin d'été (adultes et jeunes) ont tendance à hiverner dans le delta du Rhône et ses environs. Les températures hivernales affectent la taille de la population nicheuse les années suivantes. L'afflux d'oiseaux issus de populations situées plus au Sud joue un rôle important dans le maintien de cette espèce en Camargue, particulièrement après un hiver rigoureu

Search for exchange-antisymmetric two-photon states

Atomic two-photon J=0 $\leftrightarrow$J'=1 transitions are forbidden for photons of the same energy. This selection rule is related to the fact that photons obey Bose-Einstein statistics. We have searched for small violations of this selection rule by studying transitions in atomic Ba. We set a limit on the probability $v$ that photons are in exchange-antisymmetric states: $v<1.2\cdot10^{-7}$.Comment: 5 pages, 4 figures, ReVTeX and .eps. Submitted to Phys. Rev. Lett. Revised version 9/25/9

Avian malaria is absent in juvenile colonial herons (Ardeidae) but not Culex pipiens mosquitoes in the Camargue, Southern France

Apicomplexan blood parasites Plasmodium and Haemoproteus (together termed “Avian malaria”) and Leucocytozoon are widespread, diverse vector-transmitted blood parasites of birds, and conditions associated with colonial nesting in herons (Ardeidae) and other waterbirds appear perfect for their transmission. Despite studies in other locations reporting high prevalence of parasites in juvenile herons, juvenile Little Egrets (Egretta garzetta) previously tested in the Camargue, Southern France, had a total absence of malaria parasites. This study tested the hypotheses that this absence was due to insufficient sensitivity of the tests of infection; an absence of infective vectors; or testing birds too early in their lives. Blood was sampled from juveniles of four species shortly before fledging: Little Egret (n = 40), Cattle Egret (Bubulcus ibis; n = 40), Black-crowned Night-Heron (Nycticorax nycticorax, n = 40), and Squacco Heron (Ardeola ralloides; n = 40). Sensitive nested-Polymerase Chain Reaction was used to test for the presence of parasites in both birds and host-seeking female mosquitoes captured around the colonies. No malaria infection was found of in any of the heron species. Four different lineages of Plasmodium were detected in pooled samples of female Culex pipiens mosquitoes, including two in potentially infective mosquitoes. These results confirm that the absence of malaria parasites previously demonstrated in Little Egret is not due to methodological limitations. Although the prevalence of infection in mosquitoes was low, conditions within the colonies were suitable for transmission of Plasmodium. These colonial heron species may have evolved strategies for resisting malaria infection through physiological or behavioral mechanisms

Enhancement of parity and time invariance violation in Radium atom

There are several factors which lead to a huge enhancement of parity and time invariance violating effects in the Ra atom: very close electronic levels of opposite parity, the large nuclear charge Z and the collective nature of T,P-odd nuclear moments. Experiments with Radium may be used to measure it's nuclear anapole, magnetic quadrupole and Schiff moments. Such measurements provide information about parity and time invariance violating nuclear forces and electron-nucleon interactions.Comment: 4 pages, RevTe

Unterschiedliche Abheilungsdauer und Häufigkeit der Hospitalisation bei Ulcus cruris verschiedener Ursachen

BACKGROUND: Leg ulcers are a symptom of a heterogeneous group of diseases. Their treatment causes substantial costs due to the long healing times and extensive wound care measures. There is a paucity of information about healing times and the necessity of hospital treatment for leg ulcers of different etiologies. MATERIALS AND METHODS: In this retrospective study, healing times and the frequency of in-hospital treatment of 355 patients with leg ulcers attending a wound care clinic of a university hospital were examined. RESULTS: The proportion of healed ulcers was 32.0 % after 3 months and 54.3 % after 6 months with an average treatment duration of 6.1 months for all ulcers. This proportion of healed ulcers was higher for venous ulcers with 45.5 % after 3 months and 63.0 % after 6 months, whereas only 30.0 % of mixed arterial-venous ulcers and 35.0 % of hypertensive ischemic leg ulcers (HYTILU) were healed after 6 months. Of the latter group, 71 % of patients were hospitalized at least once during the observation period as compared to 47 % of patients with a venous ulcer. The duration of the hospital stay was longer for mixed ulcers and HYTILU with an average of 30 days vs. 23 days for venous ulcers. CONCLUSIONS: These data indicate that the healing times of ulcers of different etiologies differ substantially and that especially ulcers with arteriosclerosis as a causative factor have longer healing times. The fact that they require in-hospital treatment more frequently and for longer periods has significant socio-economic consequences