Multidimensional natal isotopic niches reflect migratory patterns in birds.

Naturally occurring stable isotope ratios in animal tissues allow estimation of species trophic position and ecological niche. Measuring multiple isotopes of migratory species along flyway bottlenecks offers the opportunity to sample multiple populations and species whose tissues carry information at continental scales. We measured δ2H, δ18O, δ13C, δ15N in juvenile feathers of 21 bird species captured at a migratory bottleneck in the Italian Alps. We examined if trends in individual isotopes reflected known migratory strategies and whether dietary (δ13C-δ15N) and spatially-explicit breeding origin (δ2H-δ18O) niche breadth (NB) differed among long-distance trans-Saharan (TS), short-distance (IP) and irruptive (IR) intra-Palearctic migrants, and whether they correlated with reported populations long-term trends. In both TS and IP groups, species δ2H declined with capture date, indicating that northern populations reached the stopover site later in the season, following a Type-I migration strategy. Values of δ2H indicated that breeding range of TS migrants extended farther north than IP and IR migrants. The breeding season was longer for IP migrants whose δ13C and δ15N values declined and increased, respectively, with time of capture. Average species dietary NB did not differ among migratory groups, but TS migrants displayed wider breeding origin niches, suggesting that long-distant migration is linked to broader ecological niches. Isotope origin NB well reflected species geographic range extent, while dietary NB did not correlate with literature accounts of species' diet. We found no relationship between species breeding NB and population trends in Europe, suggesting that conditions in the breeding grounds, as inferred by stable isotopes, are not the only determinant of species' long-term persistence. We demonstrate that ringing activities and isotopic measurements of passerines migrating through a bottleneck represents a unique opportunity to investigate large-scale life-history phenomena relevant to conservation.

Cell number regulator genes in Prunus provide candidate genes for the control of fruit size in sweet and sour cherry.

Striking increases in fruit size distinguish cultivated descendants from small-fruited wild progenitors for fleshy fruited species such as Solanum lycopersicum (tomato) and Prunus spp. (peach, cherry, plum, and apricot). The first fruit weight gene identified as a result of domestication and selection was the tomato FW2.2 gene. Members of the FW2.2 gene family in corn (Zea mays) have been named CNR (Cell Number Regulator) and two of them exert their effect on organ size by modulating cell number. Due to the critical roles of FW2.2/CNR genes in regulating cell number and organ size, this family provides an excellent source of candidates for fruit size genes in other domesticated species, such as those found in the Prunus genus. A total of 23 FW2.2/CNR family members were identified in the peach genome, spanning the eight Prunus chromosomes. Two of these CNRs were located within confidence intervals of major quantitative trait loci (QTL) previously discovered on linkage groups 2 and 6 in sweet cherry (Prunus avium), named PavCNR12 and PavCNR20, respectively. An analysis of haplotype, sequence, segregation and association with fruit size strongly supports a role of PavCNR12 in the sweet cherry linkage group 2 fruit size QTL, and this QTL is also likely present in sour cherry (P. cerasus). The finding that the increase in fleshy fruit size in both tomato and cherry associated with domestication may be due to changes in members of a common ancestral gene family supports the notion that similar phenotypic changes exhibited by independently domesticated taxa may have a common genetic basis.

Excitation of 1S and 3S metastable helium atoms to doubly excited states.

We present spectra of triplet and singlet metastable helium atoms resonantly photoexcited to doubly excited states. The first members of three dipole-allowed ;{1,3}P;{o} series have been observed and their relative photoionization cross sections determined, both in the triplet (from 1s2s ;{3}S;{e}) and singlet (from 1s2s ;{1}S;{e}) manifolds. The intensity ratios are drastically different with respect to transitions from the ground state. When radiation damping is included the results for the singlets are in agreement with theory, while for triplets spin-orbit interaction must also be taken into account.

X-ray absorption spectroscopy of VOCl3, CrO2Cl2, and MnO3Cl: an experimental and theoretical study.

X-ray absorption spectra of gas-phase VOCl(3) and CrO(2)Cl(2) have been measured in the metal L(2,3)-edge and O K-edge regions. The assignment of the spectral features is based on the relativistic two-component ZORA TDDFT approach. The calculations provide results in excellent agreement with the experimental spectra and prove the importance of including both configuration mixing and spin-orbit coupling in the theoretical description to obtain a reliable simulation of the transition metal L(2,3)-edge. The calculations are extended also to the MnO(3)Cl molecule to discuss the spectral variations along the series of the oxychlorides both in the metal L(2,3) and ligand O K spectra.

Photoionization cross section of Xe+ ion in the pure 5p5 2P3/2 ground level.

Coupling an ion trap with synchrotron radiation is shown here to be a powerful approach to measure photoionization cross sections on ionic species relaxed in their ground state. The photoionization efficiency curve of Xe+ ions stored in a Fourier transform ion cyclotron resonance ion trap was recorded at ELETTRA in the 20-23 eV photon energy range. Absolute cross sections were derived by comparison of the photoionization yield of Xe+ with measurements from the ASTRID merged-beam experiment. Multiconfiguration Dirac-Fock calculations were performed for the interpretation of these new data.

Reactivity of C10H7+ and C10D7+ with H2 AND D2.

We have investigated, both theoretically and experimentally, the reactions of naphthylium C10H7+ and d-naphthylium C10D7+ ions with H2 and D2. Cross sections as functions of the collision energy have been measured for a variety of reaction channels. Theoretical calculations have been carried out at the density functional theory level which utilizes the hybrid functional B3LYP and the split-valence 6-31G* basis set. The key features of the potential energy surfaces and the relevant thermochemical parameters have been calculated and they provide insights on the reaction mechanisms. The bimolecular reactivity of C10H7+ with H2 is dominated by the production of naphthalene cation C10H8+. The reaction is not a direct atom-abstraction process, but instead it proceeds via the formation of a stable intermediate complex C10H9+ of sigma type geometry, with a significant mobility of hydrogen along the ring. This mobility allows the scrambling of the hydrogen atoms and causes the successive statistical fragmentation of the complex into a variety of product channels. Elimination of one H(D) atom appears to be favored over elimination of one H2 or HD molecule. Alternatively, the intermediate complex can be stabilized either by collision with a third body or by emission of a photon.

Pattern dystrophy of the retinal pigment epithelium in Crohn's disease. A case report.

The authors describe a case of bilateral pattern dystrophy of the retinal pigment epithelium in a man with Crohn's disease. The patient was examined every 6 months over a follow-up of 30 months. The right eye presented a macroreticular dystrophy while in the left eye a butterfly pattern dystrophy was diagnosed. During the follow-up period the retinal lesion changed; in the right eye the lesion increased in size, while in the left eye the morphology of the lesion passed from the butterfly to Sjögren's type. This report adds a new ocular manifestation of Crohn's disease, emphasizing the importance of the ophthalmological follow-up in the recognition of posterior segment complications associated with this inflammatory bowel disease.

Outcome evaluation in a home palliative care service.

The complexity of assessing the impact of palliative care is much greater than in other fields of medicine, due to the shortcomings of traditional outcome indicators. We conducted a prospective study to describe the patient's quality of life at the outset and during palliative care at home and to define some potential indicators of palliative care outcomes with the aim of assessing the quality of home care as provided by a palliative care unit. Seventy-three patients who received care at home were assessed. The median survival in palliative home care was 29 days. To evaluate the degree of symptom distress, we used an Italian version of the Symptom Distress Scale. Assessing the quality-of-life pattern over time, we observed that palliative care was effective in mitigating pain and, at least in part, in stimulating appetite, curbing nausea, and controlling psychological aspects. The subscales referring to social and functional aspects steadily worsened. The difficulties encountered (the high percentage of missing data, the considerable number of patients treated for less than 10 days, etc.) should be a warning against using only one assessment instrument. It is worthwhile defining the various potential outcomes of palliative care even though all results will not always be measurable in every patients. Only a global assessment, a "multiple outcomes approach," based on different indicators, would allow for evaluation of the outcome of the care process.

[Periodic Cheyne-Stokes respiration caused by increased circulation time. Report of 2 clinical cases]. / Respiro periodico di Cheyne-Stokes da aumento del tempo di circolo. Descrizione di due casi clinici.

Two patients with heart failure and Cheyne-Stokes breathing are presented. We have discussed the possible physiopathological mechanism of Cheyne-Stokes breathing and clinical, instrumental and laboratory data for a correct diagnostic evaluation.