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Background Infective endocarditis is still a serious and deadly disease. Despite improvements in its management, the diagnosis it is not always easy and thus it is still associated with high mortality and severe complications. This is especially true for patients with prosthetic valves, that have higher risk of developing infective endocarditis and more often associated with severe complications and a higher rate of mortality. Case Description A 75–years–old woman presented to the ED for persistent low–grade fever and mild dyspnoea. She had an aortic biologic prosthetic valve implanted the year before for severe aortic stenosis. She also complained a persistent back pain, present for about three months and irresponsive to pharmacological therapy and also physiotherapy. Getting back in time, she had been hospitalized few months before for genitourinary tract infection from multi–resistant E. faecalis, treated with antibiotic therapy and then discharged after few days. She underwent a transthoracic echocardiogram in ED that showed an apparently intraprosthetic moderate aortic regurgitation, never described in the previous cardiologic controls. In the strong suspect of endocarditis complicated by systemic embolization, she also underwent transoesophageal echocardiography, that showed dehiscence of the prosthetic valve with severe paravalvular abscess and regurgitation, without rocking motion of the prosthesis. A TC scan and then a spine MRI confirmed the presence of infectious spondylodiscitis, responsible for that persistent back pain. The patient was therefore urgently sent to cardiac surgery: a Bentall procedure (aortic valve and aortic root replacement) was performed. The patient, despite the severity of the sepsis and the cardiac endocarditis, survived the surgery and after 3 weeks of intensive care hospitalization was discharged and sent back to our Department for Cardiac Rehabilitation. Entering the ward, the patient was severely deconditioned, but after about 45 days of hospitalization she was discharged fit, with good functional capacity. Conclusion This case shows the subtle but serious evolution that usually controlled infections can have in patients with high risk of endocarditis, as patients with prosthetic valves. This underlines on one hand the importance of antibiotic prophylaxis in this subset of patients, on the other hand the role of multimodality imaging for diagnosis and management of infective endocarditis and its complications.

The nonnative lake trout (Salvelinus namaycush Walbaum, 1792) population in Lake Pend Oreille, Idaho increased exponentially during 1999–2006. This led to an unsustainable level of predation mortality on kokanee (Oncorhynchus nerka Walbaum, 1792), increased the conservation threat to native bull trout (Salvelinus confluentus Suckley, 1859), and jeopardized the popular recreational fishery for kokanee and rainbow trout (Oncorhynchus mykiss Walbaum, 1792). In response, lake trout were suppressed since 2006 using incentivized angling, gill netting, and trap netting. From 2006 through 2016, 193,982 lake trout were removed (50% by gill netting; 44% by angling; 6% by trap netting). During this period, age-8 + (adult) lake trout abundance declined by 64%, age-3 (recruit) abundance declined by 56%, and mean total annual mortality (A) was 31.1%. Lake trout did not show evidence of a density-dependent response. Kokanee did not collapse and rebounded to abundances not observed since before lake trout expansion. Bull trout abundance declined during suppression, but the population was sustained. Lake trout suppression allowed a harvest fishery for kokanee and trophy fishery for rainbow trout to be restored. We conclude that suppression can be an effective management action for mitigating effects of nonnative lake trout in a large, deep lake.

Background Left ventricular hypertrophy (LVH) may be due to different causes, ranging from, benign secondary forms (athlete's heart) to severe prognosis cardiomyopathies (i.e. cardiac amyloidosis). Early and accurate differential diagnosis is important to proper patient management. LVH may be detected by echocardiography signs of hypertrophy or other abnormalities often associated to hypertrophic phenotypes. Cardiac magnetic resonance (CMR) is often used to confirm the initial diagnostic suspicion. On the best of our knowledge, there are no study specifically designed to evaluate the final impact of CMR in changing or confirming the initial diagnostic echocardiographic suspicion. Aim To evaluate the clinical prognostic correlates of CMR in patients with echocardiographic or ECG suspicion of LVH (or cardiomyopathies with hypertrophic phenotype). Methods and results We enrolled 275 pts with echocardiographic evidence of LVH. Using current guidelines, the initial echocardiographic diagnostic suspicion was: hypertrophic cardiomyopathy (HCM) in 46.9% of pts; cardiac amyloidosis in 14.5%; hypertensive LVH in 17%; aortic stenosis in 1.5%; athlete's heart in 0.3%; undetermined LVH in 17%. CMR changed the diagnosis in 42% cases: the diagnosis of HCM increased from 44% to 72% of pts; hypertensive and undetermined LVH decreased significantly (respectively to 4% and 5%). Finally, the change in diagnostic suspicion was associated to reclassification of risk of patients: Kaplan-Meier curves demonstrated that HCM and cardiac amyloidosis had worst prognosis than undetermined or hypertensive LVH. Conclusions CMR changed the echocardiographic suspicion in almost half of patients with LVH. This study highlights the indication of CMR in patient with ECG or echocardiographic suspicion of LVH. Kaplan-Meier curves Funding Acknowledgement Type of funding source: None

Hydrophobic deep eutectic solvents (DESs) have been recently introduced and acknowledged to offer remarkable advantages over the common organic solvents, thanks to their biodegradability, low toxicity and low cost. In the present paper a first study of the electrochemical properties and extraction capabilities of a prototypical hydrophobic DES, based on tetrabutylammonium chloride-decanoic acid (1:2 M ratio), is carried out. A small water content is shown to be advantageous as it dramatically affects the electrical conductivity and viscosity of the solvent, i.e. the parameters of fundamental importance in electrochemistry. A critical environmental pollutant, namely Cr(VI), has been successfully extracted from aqueous phase and amperometrically detected in the DES phase.

Background:Whether arrhythmia risks will increase if drugs with electrocardiographic (ECG) QT-prolonging properties are combined is generally supposed but not well studied. Based on available evidence, the Arizona Center for Education and Research on Therapeutics (AZCERT) classification defines the risk of QT prolongation for exposure to single drugs. We aimed to investigate how combining AZCERT drug categories impacts QT duration and how relative drug exposure affects the extent of pharmacodynamic drug–drug interactions.Methods:In a cohort of 2558 psychiatric inpatients and outpatients, we modeled whether AZCERT class and number of coprescribed QT-prolonging drugs correlates with observed rate-corrected QT duration (QTc) while also considering age, sex, inpatient status, and other QTc-prolonging risk factors. We concurrently considered administered drug doses and pharmacokinetic interactions modulating drug clearance to calculate individual weights of relative exposure with AZCERT drugs. Because QTc duration is concentration-dependent, we estimated individual drug exposure with these drugs and included this information as weights in weighted regression analyses.Results:Drugs attributing a ‘known’ risk for clinical consequences were associated with the largest QTc prolongations. However, the presence of at least two versus one QTc-prolonging drug yielded nonsignificant prolongations [exposure-weighted parameter estimates with 95% confidence intervals for ‘known’ risk drugs + 0.93 ms (–8.88;10.75)]. Estimates for the ‘conditional’ risk class increased upon refinement with relative drug exposure and co-administration of a ‘known’ risk drug as a further risk factor.Conclusions:These observations indicate that indiscriminate combinations of QTc-prolonging drugs do not necessarily result in additive QTc prolongation and suggest that QT prolongation caused by drug combinations strongly depends on the nature of the combination partners and individual drug exposure. Concurrently, it stresses the value of the AZCERT classification also for the risk prediction of combination therapies with QT-prolonging drugs.

Riassunto Obiettivi Obiettivo del presente lavoro e illustrare l’utilizzo del pericranio a copertura di un innesto di calvaria nella ricostruzione di una mandibola gravemente atrofica, a scopo implantare, al fine di proteggere l’innesto nelle fasi di attecchimento e di mantenere il suo volume nel tempo. Materiali e metodi Una paziente di 72 anni affetta da edentulia completa della mandibola, associata a grave atrofia tridimensionale, si e rivolta all’attenzione degli autori per poter risolvere il suo quadro clinico mediante una riabilitazione implantoprotesica preceduta da una ricostruzione con trapianto osseo autologo. La procedura riabilitativa ha previsto la ricostruzione mediante osso prelevato dalla teca cranica parietale e ricoperto con innesti di pericranio. Dopo 5 mesi sono stati inseriti 5 impianti osteointegrati nella regione ricostruita (mandibola anteriore interforaminale). Il mascellare superiore, che presentava elementi dentari non recuperabili a causa di una grave parodontopatia, e stato trattato mediante avulsione degli elementi dentari e l’inserimento di 6 impianti endossei. Entrambe le arcate sono state riabilitate in una seconda fase con protesi fisse su impianti. Risultati e conclusioni La procedura ha permesso un’adeguata riabilitazione implantoprotesica di entrambe le arcate dimostrando l’efficacia del pericranio nel prevenire deiscenze precoci o tardive, e della calvaria nel ricreare e mantenere adeguati volumi ossei dopo l’inserimento di impianti in zone ricostruite a causa di grave atrofia.

Riassunto Obiettivi Scopo di questo studio e valutare la percentuale di successo e di sopravvivenza di impianti inseriti in seguito a elevazione del seno mascellare in pazienti con altezza ossea residua non superiore a 5 mm, spessore osseo residuo di almeno 6 mm e mantenimento dei normali rapporti interarcata. Materiali e metodi Sono stati eseguiti 68 rialzi di seno mascellare in 60 pazienti. Tutte le procedure hanno previsto come unico materiale da innesto sinusale l’osso bovino deproteinizzato. In una seconda fase chirurgica sono stati inseriti 120 impianti. A distanza di 5 mesi dalla chirurgia implantare e stata eseguita la riabilitazione protesica. Risultati Tutti gli innesti sinusali hanno evidenziato un completo attecchimento. Il follow-up minimo dal carico protesico e stato di 24 mesi. Il riassorbimento perimplantare medio e stato di 0,85 mm (deviazione standard ± 0,36 mm). Le percentuali di sopravvivenza e di successo implantare sono state, rispettivamente, del 100% e del 97,5%. Conclusioni L’esito di questo studio sembra confermare che l’utilizzo di osso bovino deproteinizzato come materiale da innesto sinusale sia affidabile e predicibile per il mantenimento e il successo di riabilitazioni implantoprotesiche dei mascellari posteriori atrofici.

Aim of the study (i) To evaluate the survival and success rates of the new Roxolid narrow diameter implant placed in horizontally deficient ridges; and (ii) to evaluate the incidence of prosthetic complications. Materials and methods In a 24-month period (2009–2010) 18 partially or totally edentulous patients received 51 Straumann Roxolid (13 tissue level, 38 bone level) implants. Prosthetic loading of implants was either immediate (four implants; one patient) or delayed (2–12 months after placement; 47 implants; 17 patients). The patients were rehabilitated with either fixed (16 patients; 45 implants) or removable (two patients; six implants) prostheses. Results All implants successfully achieved osseointegration and all patients completed the planned prosthetic rehabilitation. Peri-implant bone resorption values ranged from 0 to 1 mm at the end of the observation period (range: 3–19 months). Implant survival and success rates were therefore 100%. No prosthetic complications occurred and all implants are still in function; therefore the prosthesis success rate was 100%. Conclusion Narrow diameter implants fabricated with the new titanium–zirconium alloy were demonstrated to be reliable in supporting both fixed and removable prosthetic rehabilitations in horizontally deficient ridges. Implant survival, peri-implant bone resorption, and prosthetic complication rates were consistent with those reported in the literature for standard diameter implants placed in non-deficient edentulous ridges.

We present new and accurate radial velocity (RV) measurements of luminous stars of all ages (old horizontal branch, intermediate-age red clump, and young blue plume, as well as red giants of a range of ages: 20.6 ≤ V ≤ 22) in the Carina dwarf spheroidal galaxy, based on low-resolution spectra collected with the FORS2 multiobject slit spectrograph at the VLT. This data set was complemented by RV measurements based on medium- and high-resolution archive spectra of brighter (V 20.6) Carina targets collected with the GIRAFFE multiobject fiber spectrograph at the VLT. The combined sample includes more than 21,340 individual spectra of ≈2000 stars covering the entire body of the galaxy. The mean (RV = 220.4 ± 0.1 km s-1) and the dispersion (σ = 11.7 ± 0.1 km s-1) of the RV distribution of candidate Carina stars (~1210 objects, 180 ≤ RV ≤ 260 km s-1, 4σ) agree quite well with similar measurements available in the literature. To further improve the statistics, the accurate RV measurements recently provided by Walker et al. were also added to the current data set. We ended up with a sample of ~1370 RV measurements of candidate Carina stars that is ≈75% larger than any previous Carina RV sample. We found that the hypothesis that the Carina RV distribution is Gaussian can be discarded at 99% confidence level. The mean RV across the body of the galaxy varies from ~220 km s-1 at a distance of 7' (~200 pc) from the center to ~223 km s-1 at 13' (~400 pc, 6σ level) and flattens out to a constant value of ~221 km s-1 at larger distances (600 pc, 4σ level). Moreover, and even more importantly, we found that in the Carina regions where the mean RV is smaller, the dispersion is also smaller, and the RV distribution is more centrally peaked (i.e., the kurtosis attains larger values). The difference in mean RV is more than 4 km s-1 (9σ level) when moving from east to west and more than 3 km s-1 (~7σ level) when moving from north to south. The RV gradient appears to be in the direction of the Carina proper motion. However, this parameter is affected by large uncertainties to reach a firm conclusion. There is evidence of a secondary maximum in RV across the Carina center (|D| ≤ 200 pc). The occurrence of a secondary feature across the Carina center is also supported by the flat-topped radial distribution based on the photometric catalog. These findings are reminiscent of a substructure with transition properties that are already detected in dwarf ellipticals, and they call for confirmation by independent investigations.

We present precise and deep optical photometry of the globular M92. Data were collected in three different photometric systems: Sloan Digital Sky Survey (g',r',i',z'; MegaCam@CFHT), Johnson-Kron-Cousins (B, V, I; various ground-based telescopes) and Advanced Camera for Surveys (ACS) Vegamag (F475W, F555W, F814W; Hubble Space Telescope). Special attention was given to the photometric calibration, and the precision of the ground-based data is generally better than 0.01 mag. We computed a new set of {\alpha}-enhanced evolutionary models accounting for the gravitational settling of heavy elements at fixed chemical composition ([{\alpha}/Fe]=+0.3, [Fe/H]=-2.32 dex, Y=0.248). The isochrones -- assuming the same true distance modulus ({\mu}=14.74 mag), the same reddening (E(B-V)=0.025+-0.010 mag), and the same reddening law -- account for the stellar distribution along the main sequence and the red giant branch in different Color-Magnitude Diagrams (i',g'-i' ; i',g'-r' ; i',g'-z' ; I,B-I ; F814W,F475W-F814W). The same outcome applies to the comparison between the predicted Zero-Age-Horizontal-Branch (ZAHB) and the HB stars. We also found a cluster age of 11 +/- 1.5 Gyr, in good agreement with previous estimates. The error budget accounts for uncertainties in the input physics and the photometry. To test the possible occurrence of CNO-enhanced stars, we also computed two sets of {\alpha}- and CNO-enhanced (by a factor of three) models both at fixed total metallicity ([M/H]=-2.10 dex) and at fixed iron abundance. We found that the isochrones based on the former set give the same cluster age (11 +/- 1.5 Gyr) as the canonical {\alpha}-enhanced isochrones. The isochrones based on the latter set also give a similar cluster age (10 +/- 1.5 Gyr). These indings support previous results concerning the weak sensitivity of cluster isochrones to CNO-enhanced chemical mixtures.

We present deep, accurate, and homogeneous multiband optical (U, B, V, I) photometry of the Carina dwarf spheroidal galaxy, based on more than 4000 individual CCD images from three different ground-based telescopes. Special attention was given to the photometric calibration, and the precision for the B, V, and I bands is generally better than 0.01 mag. We have performed detailed comparisons in the V, B - V, and V, B - I color-magnitude diagrams (CMDs) between Carina and three old, metal-poor Galactic globular clusters (GGCs, M53, M55, M79). We find that only the more metal-poor GCs (M55, [Fe/H] = -1.85; M53, [Fe/H] = -2.02 dex) provide a good match with the Carina giant branch. We have performed a similar comparison in the V, V - I CMD with three intermediate-age clusters (IACs) of the Small Magellanic Cloud (Kron 3, NGC 339, Lindsay 38). We find that the color extent of the subgiant branch (SGB) of the two more metal-rich IACs (Kron 3, [Fe/H] = -1.08; NGC339, [Fe/H] = -1.36 dex) is smaller than the range among Carina's intermediate-age stars. Moreover, the slope of the RGB of these two IACs is shallower than the slope of the Carina RGB. However, the ridge line of the more metal-poor IAC (Lindsay 38, [Fe/H] = -1.59 dex) agrees quite well with the Carina intermediate-age stars. These findings indicate that Carina's old stellar population is metal-poor and appears to have a limited spread in metallicity (Δ[Fe/H] = 0.2-0.3 dex). The Carina's intermediate-age stellar population can hardly be more metal-rich than Lindsay 38, and its spread in metallicity also appears modest. We also find that the synthetic CMD constructed assuming a metallicity spread of 0.5 dex for the intermediate-age stellar component predicts evolutionary features not supported by observations. In particular, red clump stars should attain colors that are redder than red giant stars, but this is not seen. These results are at odds with recent spectroscopic investigations suggesting that Carina stars cover a broad range in metallicity (Δ[Fe/H] ~ 1-2 dex). We also present a new method to estimate the metallicity of complex stellar systems using the difference in color between the red clump and the middle of the RR Lyrae instability strip. The observed colors of Carina's evolved stars indicate a metallicity of [Fe/H] = -1.70 ± 0.19 dex, which agrees quite well with spectroscopic measurements.

We present new intermediate-band Stroemgren photometry based on more than 300 u,v,b,y images of the Galactic globular cluster Omega Cen. Optical data were supplemented with new multiband near-infrared (NIR) photometry (350 J,H,K_s images). The final optical-NIR catalog covers a region of more than 20*20 arcmin squared across the cluster center. We use different optical-NIR color-color planes together with proper motion data available in the literature to identify candidate cluster red giant (RG) stars. By adopting different Stroemgren metallicity indices we estimate the photometric metallicity for ~4,000 RGs, the largest sample ever collected. The metallicity distributions show multiple peaks ([Fe/H]_phot=-1.73+/-0.08,-1.29+/-0.03,-1.05+/-0.02,-0.80+/-0.04,-0.42+/-0.12 and -0.07+/-0.08 dex) and a sharp cut-off in the metal-poor tail ([Fe/H]_phot-1.7 dex)., Comment: 28 pages, 22 figures, accepted on ApJ

We devised a new method to estimate globular cluster absolute ages by adopting the knee of the bending of the lower main-sequence (MS) in the Near-Infrared (NIR)J,J-Kscolor-magnitude diagram. The color difference between this feature and the Turn-Off point is strongly correlated to the cluster age. This method is marginally affected by distance and reddening uncertainties, and by the possible occurrence of differential reddening. Furthermore, the knee location does not depend on the cluster age and it is a robust theoretical prediction. We adopted accurateJ,Ks-band photometry collected with both MAD/VLT and SOFI/NTT for the Galactic globular cluster NGC 3201 to identify the location of the knee atJ~19.90 ±0.03 andJ-Ks~0.76±0.02 mag. The comparison with different sets of cluster isochrones, transformed adopting different Color–Temperature–Relations (CTRs), shows that the models are slightly redder than the observations forJ> 19 mag. This difference could be due to the presence of a calibration drift or to a problem of the CTRs in this magnitude range.

We present precise optical and near-infrared ground-based photometry of two Globular Clusters (GCs): Omega Cen and 47 Tuc. These photometric catalogs are unbiased in the Red Giant Branch (RGB) region close to the tip. We provide new estimates of the RGB tip (TRGB) magnitudes--m_I(TRGB)=9.84+/-0.05, Omega Cen; m_I(TRGB)=9.46+/-0.06, 47 Tuc--and use these to determine the relative distances of the two GCs. We find that distance ratios based on different calibrations of the TRGB, the RR Lyrae stars and kinematic distances agree with each other within one sigma. Absolute TRGB and RR Lyrae distance moduli agree within 0.10--0.15 mag, while absolute kinematic distance moduli are 0.2--0.3 mag smaller. Absolute distances to 47 Tuc based on the Zero-Age-Horizontal-Branch and on the white dwarf fitting agree within 0.1 mag, but they are 0.1--0.3 mag smaller than TRGB and RR Lyrae distances.

We discuss how a wide field imager with very high spatial resolution on a relatively small telescope–but located in an observing site with very good seeing–might constrain the fraction of binary stars in Galactic globular clusters. We also mention the role that the new data might play in investigating advanced evolutionary phases of low-mass stars. Moreover, we discuss the role that an Extremely Large Telescope might have on the longstanding problem of cosmic distances and stellar populations. In particular, we discuss the impact that the detection of Cepheids in galaxies at the distance of the Coma cluster and of RR Lyrae stars in galaxies at the distance of the Virgo cluster might have on the calibration of secondary distance indicators.

We present new Near-Infrared (J,K) magnitudes for 114 RR Lyrae stars in the globular cluster Omega Cen (NGC 5139) which we combine with data from the literature to construct a sample of 180 RR Lyrae stars with J and K mean magnitudes on a common photometric system. This is presently the largest such sample in any stellar system. We also present updated predictions for J,K-band Period-Luminosity relations for both fundamental and first-overtone RR Lyrae stars, based on synthetic horizontal branch models with metal abundance ranging from Z=0.0001 to Z=0.004. By adopting for the Omega Cen variables with measured metal abundances an alpha-element enhancement of a factor of 3 (about 0.5 dex) with respect to iron we find a true distance modulus of 13.70 (with a random error of 0.06 and a systematic error of 0.06), corresponding to a distance d=5.5 Kpc (with both random and systematic errors equal to 0.03 Kpc). Our estimate is in excellent agreement with the distance inferred for the eclipsing binary OGLEGC-17, but differ significantly from the recent distance estimates based on cluster dynamics and on high amplitude Delta Scuti stars., Comment: 24 pages, 7 figures, accepted for publication on The Astrophysical Journal

We report new HST/WFPC2 photometry for 10 globular clusters (GC) in M31 observed in F5555W(V) and F814W(I). Additionally we have reanalyzed HST archival data of comparable quality for 2 more GCs. Extraordinary care is taken to account for the effects of blended stellar images and required field subtraction. We thus reach 1 mag fainter than the horizontal branch (HB) even in unfavorable cases. We present the color-magnitude diagrams (CMDs) and discuss their main features also in comparison with the properties of the Galactic GCs. This analysis is augmented with CMDs previously obtained and discussed by Fusi Pecci et al. (1996) on 8 other M31 clusters. We report the following significant results: 1. The locus of the red giant branches give reliable metallicity determinations which compare generally very well with ground-based integrated spectroscopic and photometric measures, as well as giving good reddening estimates. 2. The HB morphologies show the same behavior with metallicity as the Galactic GCs, with indications that the 2nd-parameter effect can be present in some GCs of our sample. However, at [Fe/H] ~ -1.7 we observe a number of GCs with red HB morphology such that the HB type versus [Fe/H] relation is offset from the MW and resembles that of the Fornax dwarf spheroidal galaxy. One explanation for the offset is that they are younger than their MW counterparts by 1-2 Gyr. 3. The Mv(HB)-[Fe/H] relationship has been determined and the slope (~0.20) is very similar to the values derived from RR Lyrae stars in the MW and the LMC. The zero-point of this relation based on the assumed distance modulus (m-M)o(M31)=24.47+/-0.03 is consistent with (m-M)o(LMC)=18.55.

We present three different optical and near-infrared (NIR) data sets for evolved stars in the Galactic Globular Cluster Omega Cen The comparison between observations and homogeneous sets of stellar isochrones and Zero-Age Horizontal Branches provides two reasonable fits. Both of them suggest that the so-called anomalous branch has a metal-intermediate chemical composition (-1.1 < [Fe/H] < -0.8) and is located ~500 pc beyond the bulk of Omega Cen stars. These findings are mainly supported by the shape of the subgiant branch in four different color-magnitude diagrams (CMDs). The most plausible fit requires a higher reddening, E(B-V)=0.155 vs. 0.12, and suggests that the anomalous branch is coeval, within empirical and theoretical uncertainties, to the bulk of Omega Cen stellar populations. This result is supported by the identification of a sample of faint horizontal branch stars that might be connected with the anomalous branch. Circumstantial empirical evidence seems to suggest that the stars in this branch form a clump of stars located beyond the cluster.

We present first results concerning the detection of variable stars in the Carina dwarf Spheroidal from B, V images collected with the 4-m CTIO telescope. We show a sample of candidate variables spanning from the tip of the Red Giant Branch down to the Main Sequence turn off. Finally, we discuss the future photometric and spectroscopic developments of this project.

HST observations of the core of four galactic globular clusters allowed us to obtain interesting clues about the influence of the environment on the star distribution along the horizontal branch. The chemical composition and the age of the target clusters have been derived through a detailed analysis of the (V, V-I) color-magnitude diagrams. The photometric metallicities have been found in close agreement with the recent spectroscopic determinations. The four clusters are coeval within the uncertainties. Hence, age and metallicity cannot account for the difference in the horizontal-branch morphologies, as shown by a comparison with theoretical zero-age horizontal-branch sequences and synthetic horizontal branches taken from the literature. Our analysis further supports the hypothesis according to which dense environments cause the occurrence of the so-called "blue tails" in the horizontal branches of galactic globular clusters. The use of HST, as well as of ground-based data for some clusters, enabled us to study the radial distribution of the various evolved populations, starting from the very center. We thus discovered that blue stragglers are, in general, more concentrated while the horizontal and the red giant branch do not display a markedly different trend with the distance from the cluster center, although the red giant branch of NGC 6626 is more concentrated than the horizontal branch.

Using observations from the Hubble Space Telescope archive, color-magnitude diagrams (CMDs) have been constructed for globular cluster 4 in the Fornax dwarf spheroidal galaxy and its surrounding field. These diagrams extend below the main-sequence turnoffs and have yielded measurements of the ages of the populations. The most prominent features of the CMD of the Fornax field population are a heavily populated red clump of horizontal-branch (HB) stars, a broad red giant branch (RGB), and a main sequence that spans a large range in luminosity. In this CMD, there are very few stars at the positions of the HBs of the five globular clusters in Fornax, which suggests that only a very small fraction of the field population resembles the clusters in age and chemical composition. The large span in luminosity of the main sequence suggests that star formation began in the field 12 Gyr ago and continued to 0.5 Gyr ago. There are separate subgiant branches in the CMD, which indicates that the star formation was not continuous but occurred in bursts. The CMD of cluster 4 has a steep RGB, from which we estimate [Fe/H] -2.0. This is considerably lower than estimates from the integrated light of the cluster, and the origins of this discrepancy are discussed. Cluster 4 has a very red HB and is, therefore, a prime example of the second-parameter effect. Comparisons of cluster 4 with the other Fornax clusters and with M68, a very metal-poor globular cluster of the Galactic halo, reveal that cluster 4 is 3 Gyr younger than these other clusters, which have much bluer HBs. This age difference is consistent with the prediction that age is the second parameter to within the uncertainties. The CMD of cluster 4 is virtually identical to that of the unusual globular cluster of the Galactic halo Ruprecht 106, which suggests that they have very similar ages and chemical compositions. We discuss the possibility that cluster 4 also resembles R106 in having a higher [Fe/H] than is indicated by its steep RGB and also a lower [α/Fe] ratio than is usual for a globular cluster, as indicated by some recent observations of R106. The CMDs of the five Fornax clusters indicate that cluster age is a major—but probably not the sole—second parameter. Buonanno et al. recently concluded that cluster density probably influenced the HB morphologies of clusters 1, 2, 3, and 5. Despite a very large difference in central density, the HBs of cluster 4 and R106 are very similar. This suggests that density may act as a second parameter in clusters that have HBs that are on the verge of moving toward the blue or are already blue for another reason, such as very old age.

From observations with the Hubble Space Telescope, color-magnitude diagrams (CMDs) have been constructed for the four most metal-poor globular clusters in the Fornax dSph galaxy. These diagrams confirm that cluster 1 has a redder horizontal-branch (HB) morphology than the other three clusters despite its similarity in metallicity (the second parameter effect). The near coincidence of the fiducial lines of the CMDs indicates that the ages of the Fornax clusters are identical to within 1 Gyr. Since a larger range is predicted if age is the second parameter, we conclude that either the sensitivity of the HB to age has been underestimated or some parameter besides age is acting as a second parameter. The Fornax clusters exhibit a correlation between HB morphology and central density that is similar to the one among galactic globular clusters, which suggests that some mechanism related to density is influencing HB morphology. No significant differences in age have been found between the Fornax clusters and the metal-poor galactic globular clusters M68 and M92, which suggests that cluster formation began nearly simultaneously over a large volume of space. Subject headings: galaxies: star clusters — globular clusters: general — Local Group

We report the results of the observations in the JHK bands of 12 globular clusters in the LMC, and present CMDs down to K=16 for about 450 stars. We merge the data with the BV ones presented in paper I and use the merged data to study the evolution of integrated magnitudes and colours of SSPs. We find that the AGB contributes about 60 percent of integrated clusters light in K, while the contribution from RGB is correlated with the age of the cluster. The age at which the first appearance of the RGB takes place depends on the models adopted ranging from about 600 Myr in the "classical" models to about 1.5 Gyr with the "overshooting" models. Both models give the same fractional contribution of the RGB to the cluster light, in agreement with the Fuel Consumption Theorem. The overall picture is consistent with the early conclusions of Persson et al. 1983 and Frogel et al. 1990 that J-K colour is driven by AGB stars, V-K is controlled by AGB and RGB stars and B-V is partially influenced by the whole population redder than the RGB clump, but is strongly dependent on the fading and reddening of the TO stars with age., 26 pages, 15 figures available on request, uuencoded compressed postscript file with tables included, BAP 08-1994-021-OAB

We have performed accurate iron abundance measurements for 44 red giants (RGs) in the Carina dwarf spheroidal (dSph) galaxy. We used archival, high-resolution spectra (R~38,000) collected with UVES at ESO/VLT either in slit mode (5) or in fiber mode (39, FLAMES/GIRAFFE-UVES). The sample is more than a factor of four larger than any previous spectroscopic investigation of stars in dSphs based on high-resolution (R>38,000) spectra. We did not impose the ionization equilibrium between neutral and singly-ionized iron lines. The effective temperatures and the surface gravities were estimated by fitting stellar isochrones in the V, B-V color-magnitude diagram. To measure the iron abundance of individual lines we applied the LTE spectrum synthesis fitting method using MARCS model atmospheres of appropriate metallicity. We found evidence of NLTE effects between neutral and singly-ionized iron abundances. Assuming that the FeII abundances are minimally affected by NLTE effects, we corrected the FeI stellar abundances using a linear fit between FeI and FeII stellar abundance determinations. We found that the Carina metallicity distribution based on the corrected FeI abundances (44 RGs) has a weighted mean metallicity of [Fe/H]=-1.80 and a weighted standard deviation of sigma=0.24 dex. The Carina metallicity distribution based on the FeII abundances (27 RGs) gives similar estimates ([Fe/H]=-1.72, sigma=0.24 dex). The current weighted mean metallicities are slightly more metal poor when compared with similar estimates available in the literature. Furthermore, if we restrict our analysis to stars with the most accurate iron abundances, ~20 FeI and at least three FeII measurements (15 stars), we found that the range in iron abundances covered by Carina RGs (~1 dex) agrees quite well with similar estimates based on high-resolution spectra., Accepted for publication in PASP, 16 pages, 7 figures, 3 tables, 1 MR table Note: the electronic version of Table1 is included, but commented, in the tex file

We present BV CCD-data for 11 intermediate-age LMC clusters; the main conclusions are: 1. in the (V_to, V_cl,m) and (V-to, (V_to-V_cl,m)) planes the models yield a good overall description of the data; 2. with the current sample, it is impossible to firmly choose between "classical" and "overshooting" models; 3. the separation in colour between the MS band and the Red He-burning Clump is smaller than predicted by theoretical tracks; 4. the existence of the so-called "RGB phase-transition (Renzini and Buzzoni 1986) seems to be confirmed., 62 pages, 37 figures and tables 6 to 16 available on request, uuencoded compressed postscript file with tables 1-5 and 17-18 included, BAP 08-1994-020-OAB

We present a new theoretical calibration of the Stroemgren metallicity index hk by using alpha-enhanced evolutionary models transformed into the observational plane by using atmosphere models with the same chemical mixture. We apply the new Metallicity--Index--Color (MIC) relations to a sample of 85 field red giants (RGs) and find that the difference between photometric estimates and spectroscopic measurements is on average smaller than 0.1 dex with a dispersion of sigma = 0.19 dex. The outcome is the same if we apply the MIC relations to a sample of eight RGs in the bulge globular cluster NGC6522, but the standard deviation ranges from 0.26 (hk, v-y) to 0.49 (hk, u-y). The difference is mainly caused by a difference in photometric accuracy. The new MIC relations based on the (Ca-y) color provide metallicities systematically more metal-rich than the spectroscopic ones. We found that the Ca-band is affected by Ca abundance and possibly by chromospheric activity., Comment: Accepted for publication on The Astrophysical Journal Letters

We present new empirical estimates of the ΔV bump HB parameter for 15 Galactic globular clusters (GGCs) using accurate and homogeneous ground-based optical data. Together with similar evaluations available in the literature, we ended up with a sample of 62 GGCs covering a very broad range in metal content (–2.16 dex ≤ [M/H] ≤ –0.58 dex). Adopting the homogeneous metallicity scale provided either by Kraft & Ivans or by Carretta et al., we found that the observed ΔV bump HB parameters are larger than predicted. In the metal-poor regime ([M/H] –1.7, –1.6 dex) 40% of GCs show discrepancies of 2σ (≈0.40 mag) or more. Evolutionary models that account either for α- and CNO-enhancement or for helium enhancement do not alleviate the discrepancy between theory and observations. The outcome is the same if we use the new solar heavy-element mixture. The comparison between α- and CNO-enhanced evolutionary models and observations in the Carretta et al. metallicity scale also indicates that observed ΔV bump HB parameters, in the metal-rich regime ([M/H] ≥ 0), might be systematically smaller than predicted.

We present a new method to estimate the absolute ages of stellar systems. This method is based on the difference in magnitude between the main sequence turn-off (MSTO) and a well defined knee located along the lower main sequence (MSK). This feature is caused by the collisionally induced absorption of molecular hydrogen and it can be easily identified in near-infrared (NIR) and in optical-NIR color-magnitude diagrams of stellar systems. We took advantage of deep and accurate NIR images collected with the Multi-Conjugate Adaptive Optics Demonstrator temporarily available on the Very Large Telescope and of optical images collected with the Advanced Camera for Surveys Wide Field Camera on the Hubble Space Telescope and with ground-based telescopes to estimate the absolute age of the globular NGC3201 using both the MSTO and the Delta(MSTO-MSK). We have adopted a new set of cluster isochrones and we found that the absolute ages based on the two methods agree to within one sigma. However, the errors of the ages based on the Delta(MSTO-MSK) method are potentially more than a factor of two smaller, since they are not affected by uncertainties in cluster distance or reddening.Current isochrones appear to predict slightly bluer (~0.05mag) NIR and optical-NIR colors than observed for magnitudes fainter than the MSK., 8 pages, 4 figures, accepted for publication on ApJL

We investigate the stellar content of the starburst dwarf galaxy IC10 using accurate and deep optical data collected with the Advanced Camera for Surveys and with the Wide Field Planetary Camera 2 on board the Hubble Space Telescope. The comparison between theory and observations indicates a clear change in age distribution when moving from the center toward the external regions. Moreover, empirical calibrators and evolutionary predictions suggest the presence of a spread in heavy element abundance of the order of one-half dex. The comparison between old and intermediate-age core He-burning models with a well defined overdensity in the color-magnitude diagram indicates the presence of both intermediate-age, red clump stars and of old, red horizontal branch stars., 7 pages, 4 figures, 1 table. Accepted for publication in ApJL

We present accurate new ultraviolet and optical BVI photometry for the Galactic globular cluster ngc2808, based on both ground-based and archival HST imagery. From this we have selected a sample of ~2,000 HB stars; given the extensive wavelength range considered and the combination of both high-angular-resolution and wide-field photometric coverage, our sample should be minimally biased. We divide the HB stars into three radial bins and find that the relative fractions of cool, hot and extreme HB stars do not change radically when moving from the center to the outskirts of the cluster: the difference is typically smaller than ~2sigma. These results argue against the presence of strong radial differentiation among any stellar subpopulations having distinctly different helium abundances. The ratio between HB and RG stars brighter than the ZAHB steadly increases when moving from the innermost to the outermost cluster regions. The difference is larger than ~4sigma and indicates a deficiency of bright RGs in the outskirts of the cluster., accepted for publication on ApJ Letters

We present the strategies adopted in the relative and absolute calibration of two different data sets: U,B,V,I-band images collected with the Wide Field Imager (WFI∈dexWFI) mosaic camera mounted on the 2.2 m ESO/MPI Telescope and u,v,b,y calastrom images collected with the 1.54 m Danish Telescope (ESO, La Silla). In the case of the WFI camera we adopted two methods for the calibration, one for images collected before 2002, with the ESO filters U/38ESO841 and B/99ESO842, and a different one for data secured after 2002, with the filters U/50ESO877 and B/123ESO878. The positional and color effects turned out to be stronger for images collected with the old filters. The eight WFI chips of these images were corrected one by one, while in the case of images secured with the new filters, we corrected the entire mosaic in a single step. In the case of the Danish data set, we compared point-spread function (PSF) and aperture photometry for each frame, finding a trend in both the X and Y directions of the chip. The corrections resulted in a set of first and second order polynomials to be applied to the instrumental magnitudes of each individual frame as a function of the star position.

We present an extensive spectroscopic investigation on evolved old- and intermediate-age stellar tracers of the Carina dSph galaxy. We discuss the approach we devised to calibrate the two multi-object spectrographs (FLAMES, FORS2) available at the European Southern Observatory. Pros and cons of the two instruments are also mentioned. Finally, we present preliminary results concerning the radial velocity measurements and the comparison with data from the literature

In the framework of a program for the monitoring of Supernovae in the Near-Infrared (NIR) carried out by the Teramo, Rome and Pulkovo observatories with the AZT-24 telescope, we observed the Supernova SN2006jc in the J,H,K photometric bands during a period of 7 months, starting ~36 days after its discovery. Our observations evidence a NIR re-brightening, peaking ~70 days after discovery, along with a reddening of H-K and J-H colors until 120 days from discovery. After that date, J-H seems to evolve towards bluer colors. Our data, complemented by IR, optical, UV and X-ray observations found in the literature, show that the re-brightening is produced by hot dust surrounding the supernova, formed in the interaction of the ejecta with dense circumstellar matter., 22 pages, 5 figures, submitted to ApJ

We present deep and precise photometry (F435, F625W, F658N) of Omega Cen collected with the Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). We have identified ~ 6,500 white dwarf (WD) candidates, and the ratio of WD and Main Sequence (MS) star counts is found to be at least a factor of two larger than the ratio of CO-core WD cooling and MS lifetimes. This discrepancy is not explained by the possible occurrence of a He-enhanced stellar population, since the MS lifetime changes by only 15% when changing from a canonical (Y=0.25) to a He-enhanced composition (Y=0.42). The presence of some He-core WDs seems able to explain the observed star counts. The fraction of He WDs required ranges from 10% to 80% depending on their mean mass and it is at least five times larger than for field WDs. The comparison in the Color Magnitude Diagram between theory and observations also supports the presence of He WDs. Empirical evidence indicates that He WDs have been detected in stellar systems hosting a large sample of extreme horizontal branch stars, thus suggesting that a fraction of red giants might avoid the He-core flash., 14 pages, 3 figures, accepted for publication to ApJ

We adopted uvby Strömgren photometry to investigate the metallicity distribution of ω Cen Red Giant (RG) stars. We provided a new empirical calibration of the Str¨omgren m1 ≡ (v−b)−(b−y) metallicity index based on cluster stars. The new calibration has been applied to a sample of ω Cen RGs. The shape of the estimated metallicity distribution is clearly asymmetric, with a sharp cut-off at low metallicities ([F e/H] < −2.0) and a metal-rich tail up to [F e/H] ∼ 0.0. Two main metallicity peaks have been identified, around [F e/H] ≈ −1.9 and −1.3 dex, and a metal-rich shoulder at ≈ −0.2 dex., IAU Symposium 241 Stellar Populations as Building Blocks of Galaxies, December 10-16, 2006, Canary Islands, Spain, Series: Proceedings of the International Astronomical Union

We present an extensive photometry on HB, RGB, and MSTO stars in Omega Cen. The central regions of the cluster were covered with a mosaic of F435W, F625W, and F658N-band data collected with ACS/HST. The outer reaches were covered with a large set of U,B,V,I-band data collected with the WFI@2.2m ESO/MPI telescope. The final catalogue includes ~1.7 million stars. We identified ~3,200 likely HB stars and ~12,500 stars brighter than the subgiant branch and fainter than the RGB bumps. The HB morphology changes with the radial distance. The relative number of extreme HB stars decreases from ~30% to ~21% when moving from the center toward the outer regions of the cluster, while the fraction of less hot HB stars increases from ~62% to ~72%. We performed a detailed comparison between observed ratios of different stellar tracers and predictions based on canonical evolutionary models with a primordial helium (Y=0.23) content and metal abundances (Z=0.0002,0.001) that bracket the observed spread in metallicity of Omega Cen stars. We found that the empirical star counts of HB stars are on average larger (30%-40%) than predicted. Moreover, the rate of HB stars is 43% larger than the MSTO rate. The discrepancy between the rate of HB compared with the rate of RG and MSTO stars supports the evidence that we are facing a true excess of HB stars. The same comparison was performed by assuming a mix of stellar populations made with 70% of canonical stars and 30% of He-enhanced stars. The discrepancy between theory and observations decreases by a factor of two when compared with rates predicted by canonical He content models, but still 15%-25% (Y=0.42) and 15%-20% (Y=0.33) higher than observed. Furthermore, the ratio between HB and MSTO star counts are ~24% (Y=0.42) and 30% (Y=0.33) larger than predicted lifetime ratios., Comment: 54 pages, 17 figures,to be published in ApJ, see link at http://stellari.wiki.zoho.com

We present a new calibration of the Stroemgren metallicity index m1 using red giant (RG) stars in 4 globular clusters (GCs:M92,M13,NGC1851,47Tuc) with metallicity ranging from [Fe/H]=-2.2 to -0.7, marginally affected by reddening (E(B-V), 51 pages, 19 figures, accepted for submission to ApJ

International Astronomical Union Symposium 241: Stellar Populations as Building Blocks of Galaxies, December 10-16, 2006, La Palma, Tenerife, Spain, Series: Proceedings of the International Astronomical Union; no. 2, issue S241

Background Recently, the affective relationship between humans and animals has shown a potentially beneficial effects in clinical domains. However, the claim of different studies of the benefits of animal-assisted activities (AAA) is still lacking evidence base data. Objectives To gain insights into the effectiveness of AAA, physiotherapy and psychological support in SSc. Methods 12 SSc female patients (mean age of 60.52±8.3) were treated once a week by a team made of a dog-handler a rheumatologist and a psychologist. They underwent 10 dog-assisted interventions. At onset and after 3 months, the questionnaires and self reports were completed: pain evaluation (VAS 0-100), emotional and affective evaluation (Happy Face-Sad Face Scale), state anxiety (STAI), and a specific designed self report on the liking and satisfaction of the AAA interventions (AAA-Q). Results Significant improvements were reported for pain perception, mood, and other measures of distress among patients after AAA. Pain decreased significantly (p 76±7.5 vs 62±4.3) significantly different before and after AAA (p Conclusions This is the first study measuring the efficacy of AAA (with dogs) on the physiological, emotional, social well-being and pain perception in SSc. The study provides the evidence for pain control with enhancement of the psychosocial well-being. AAA integrated with the traditional medical approach may provide a good support for SSc patients. Disclosure of Interest None declared

We present a photometric survey aimed at the identification of variable stars in the galactic globular cluster ω Cen. Our photometric catalogue is based on ∼ 400 exposures of the central region of the cluster(Fov ∼ 15′ × 15′) collected with the Danish Telescope. The catalogue has an accuracy of about ∼ 0.02 mag at B ∼ 18 mag. We present here preliminary results concerning the possible identification of two variable stars and an eclipsing binary candidate in ω Cen.