Temporal dynamics and spatial patterns of Galliform birds in Trentino – Italy.

This study examines the population dynamics of 5 species of closely related galliform birds in the Dolomites, north-east Italian Alps. The aim was to assess the dynamics of these populations at the edge of their European distribution and to investigate the patterns of spatial synchrony. Three main types of data sets were used in the analysis. First, the hunting statistics collected from 210 hunting areas between 1965 and 1994 for each of the 5 galliform species. Second, rock partridge count data from 29 sample areas during the period 1994 to 1998. Third, guts helminths collected from rock partridge shot between 1995 and 1998. Tetraonid populations at the edge of their southern European distribution exhibited a weak tendency to cycle. These cycles only showed significant negative autocorrelation at half the cycle period and were classified as phase-forgetting quasi-cycles contrasting with the more regular oscillations recorded in the same species in Finland. Cycles were not found in time series of black grouse Tetrao tetrix or capercaillie Tetrao urogallus. Rock partridge Alectoris graeca saxatilis exhibited a higher tendency to fluctuate. Rock partridge populations declined between 1965 and 1975 with populations in the western province declining earlier. Total winter loss and spring to summer loss of adults were the most important population parameters influencing the year to year change in numbers. There was some compensation to hunting mortality. The hypothesis that macroparasites may be of significance in destabilising partridge abundance and generating cyclic oscillations was examined by investigating the intensity of parasite infection in cyclic and non cyclic populations. Ascaridia compar and Heterakis tenuicauda were prevalent in the rock partridge populations and significantly greater in cyclic populations than non-cyclic populations. There were large variations in synchrony both within and between species and only weak negative relationships between synchrony and distance. Species in neighbouring habitats were more likely to be in synchrony than species separated by several habitats. A detailed spatial analysis on rock partridge populations found an increase in synchrony with scale from the population to meta-population level. Rock partridge clustered in two groups DRY and WET and synchrony was stronger in populations in the same habitat with populations in the dry habitat showing a higher tendency to cycle. The modelling of the long term dynamics of spatially structured populations indicated that environmental stochasticity was the main cause of synchrony although there is also some dispersal between populations and the importance of this varied between species. Population viability analysis of the grey partridge Perdix perdix in populations in Britain between 1930-1960 and the "declining" continental populations from 1970 to 1994 confirms that the UK populations prior to 1960 were more resilient than the continental populations. Even very small harvesting cannot be tolerated by the present continental populations and this may indicate that the persistence of hunting activity, although with a limited effort, has contributed to the extinction of many sub-populations and is critically threatening the remaining ones

Which solar neutrino data favour the LMA solution?

Assuming neutrino oscillations, global analyses of solar data find that the LOW solution is significantly disfavoured, leaving LMA as the best solution. But the preference for LMA rests on three weak hints: the spectrum of earth matter effects (Super-Kamiokande sees an overall day/night asymmetry only at 1 sigma), the Cl rate (but LMA and LOW predictions are both above the measured value), the Ga rate (newer data decrease towards the LOW predictions both in GNO and SAGE). Only new data will tell us if LMA is the true solution.Comment: 4 pages, 2 figure

Effects of blood transfusion on exercise capacity in thalassemia major patients

Anemia has an important role in exercise performance. However, the direct link between rapid changes of hemoglobin and exercise performance is still unknown.To find out more on this topic, we studied 18 beta-thalassemia major patients free of relevant cardiac dysfunction (age 33.5±7.2 years,males = 10). Patients performed a maximal cardiopulmolmonary exercise test (cycloergometer, personalized ramp protocol, breath-by-breath measurements of expired gases) before and the day after blood transfusion (500 cc of red cell concentrates). After blood transfusion, hemoglobin increased from 10.5±0.8 g/dL to 12.1±1.2 (p<0.001), peak VO2 from 1408 to 1546mL/min (p<0.05), and VO2 at anaerobic threshold from 965 to 1024mL/min (p<0.05). No major changes were observed as regards heart and respiratory rates either at peak exercise or at anaerobic threshold. Similarly, no relevant changes were observed in ventilation efficiency, as evaluated by the ventilation vs. carbon dioxide production relationship, or in O2 delivery to the periphery as analyzed by the VO2 vs. workload relationship. The relationship between hemoglobin and VO2 changes showed, for each g/dL of hemoglobin increase, a VO2 increase = 82.5 mL/min and 35 mL/min, at peak exercise and at anaerobic threshold, respectively. In beta-thalassemia major patients, an acute albeit partial anemia correction by blood transfusion determinates a relevant increase of exercise performance, observed both at peak exercise and at anaerobic threshold

Abelian family symmetries and the simplest models that give theta13=0 in the neutrino mixing matrix

I construct predictive models of neutrino mass and mixing that have fewer parameters, both in the lepton sector and overall, than the default seesaw model. The predictions are theta13=0 and one massless neutrino, with the models having a Z4 or Z2 symmetry and just one extra degree of freedom: one real singlet Higgs field. It has been shown that models with an unbroken family symmetry, and with no Higgs fields other than the Standard Model Higgs doublet produce masses and mixing matrices that have been ruled out by experiment. Therefore, this article investigates the predictions of models with Abelian family symmetries that involve Higgs singlets, doublets and triplets, in the hope that they may produce the maximal and minimal mixing angles seen in the best fit neutrino mixing matrix. I demonstrate that these models can only produce mixing angles that are zero, maximal or unconfined by the symmetry. The maximal mixing angles do not correspond to physical mixing, so an Abelian symmetry can, at best, ensure that theta13=0, while leaving the solar and atmospheric mixing angles as free parameters. To generate more features of the best-fit mixing matrix a model with a non-Abelian symmetry and a complicated Higgs sector would have to be used.Comment: 16 pages, no figure

Evolutionary History and Attenuation of Myxoma Virus on Two Continents

The attenuation of myxoma virus (MYXV) following its introduction as a biological control into the European rabbit populations of Australia and Europe is the canonical study of the evolution of virulence. However, the evolutionary genetics of this profound change in host-pathogen relationship is unknown. We describe the genome-scale evolution of MYXV covering a range of virulence grades sampled over 49 years from the parallel Australian and European epidemics, including the high-virulence progenitor strains released in the early 1950s. MYXV evolved rapidly over the sampling period, exhibiting one of the highest nucleotide substitution rates ever reported for a double-stranded DNA virus, and indicative of a relatively high mutation rate and/or a continually changing selective environment. Our comparative sequence data reveal that changes in virulence involved multiple genes, likely losses of gene function due to insertion-deletion events, and no mutations common to specific virulence grades. Hence, despite the similarity in selection pressures there are multiple genetic routes to attain either highly virulent or attenuated phenotypes in MYXV, resulting in convergence for phenotype but not genotype. © 2012 Kerr et al

7Be ^7 Be Neutrino Signal Variation in KamLAND

Large Mixing Angle (LMA) neutrino oscillation is the main solution for the long-standing Solar Neutrino Problem (SNP). Whether there is any subdominant effect accompanying the dominant LMA solution can not be ruled out at the moment, but will be settled by the forthcoming data from highly skilled real time experiments targeting essentially the low energy domain of solar neutrinos. Assuming a subdominant effect converting one of the active neutrinos into a sterile partner in the varying solar field with changing sunspot activity, we performed field-profile-independent predictions for $^7 Be$ neutrino signal variation, which might be tested in the KamLAND's future solar neutrino detection program. We found that after a substantial reduction of background and running of KamLAND solar mode through the sunspot maximum period (around 2010 - 2012), when the solar field at the resonance may vary from few $kG$ to $300~kG$, the subdominant time variation effect might be clearly visible (more than $5\sigma$) for $^7 Be$ neutrinos.Comment: 12 pages, 4 figures, typos corrected. To appear in JHE

A new approach to the front-end readout of cryogenic ionization detectors

We present a novel approach to the readout of ionization detectors. The solution allows to minimize the number of components and the space occupation close to the detector. This way a minimal impact is added on the radioactive background in those experiments where very low signal rates are expected, such as GERDA and MAJORANA. The circuit consists in a JFET transistor and a remote second stage. The DC feedback path is closed using a diode. Two signal cables are only necessary for biasing and readout.Comment: 14 pages, 15 figures and 15 equation

Lung function with carvedilol and bisoprolol in chronic heart failure: is beta selectivity relevant?

BACKGROUND: Carvedilol is a beta-blocker with similar affinity for beta1- and beta2 receptors, while bisoprolol has higher beta1 affinity. The respiratory system is characterized by beta2-receptor prevalence. Airway beta receptors regulate bronchial tone and alveolar beta receptors regulate alveolar fluid re-absorption which influences gas diffusion. AIMS: To compare the effects of carvedilol and bisoprolol on lung function in patients with chronic heart failure (CHF). METHODS AND RESULTS: We performed a double-blind, cross-over study in 53 CHF patients. After 2 months of full dose treatment with either carvedilol or bisoprolol, we assessed lung function by salbutamol challenge, carbon monoxide lung diffusion (DLCO), including membrane conductance (DM), and gas exchange during exercise. FEV1 and FVC were similar; after salbutamol FEV1 was higher with bisoprolol (p<0.04). DLco was 82+/-21% of predicted with carvedilol and 90+/-20% with bisoprolol (p<0.01) due to DM changes. Peak VO2 was 17.8+/-4.5 mL/min/kg on bisoprolol and 17.0+/-4.6 on carvedilol, (p<0.05) with no differences in bronchial tone (same expiratory time) throughout exercise. Differences were greater in the 22 subjects with DLCO<80%. CONCLUSION: Carvedilol and bisoprolol have different effects on DLCO and response to salbutamol. DLCO differences, being DM related, are due to changes in active membrane transport which is under alveolar beta2-receptor control. Peak VO2 was slightly higher with bisoprolol particularly in CHF patients with reduced DLCO

Probing long-range leptonic forces with solar and reactor neutrinos

In this work we study the phenomenological consequences of the existence of long-range forces coupled to lepton flavour numbers in solar neutrino oscillations. We study electronic forces mediated by scalar, vector or tensor neutral bosons and analyze their effect on the propagation of solar neutrinos as a function of the force strength and range. Under the assumption of one mass scale dominance, we perform a global analysis of solar and KamLAND neutrino data which depends on the two standard oscillation parameters, \Delta m^2_{21} and \tan^2\theta_{12}, the force coupling constant, its range and, for the case of scalar-mediated interactions, on the neutrino mass scale as well. We find that, generically, the inclusion of the new interaction does not lead to a very statistically significant improvement on the description of the data in the most favored MSW LMA (or LMA-I) region. It does, however, substantially improve the fit in the high-\Delta m^2 LMA (or LMA-II) region which can be allowed for vector and scalar lepto-forces (in this last case if neutrinos are very hierarchical) at 2.5\sigma. Conversely, the analysis allows us to place stringent constraints on the strength versus range of the leptonic interaction.Comment: 20 pages, 8 figure