Multiple populations in globular clusters. Lessons learned from the Milky Way globular clusters

Recent progress in studies of globular clusters has shown that they are not simple stellar populations, being rather made of multiple generations. Evidence stems both from photometry and spectroscopy. A new paradigm is then arising for the formation of massive star clusters, which includes several episodes of star formation. While this provides an explanation for several features of globular clusters, including the second parameter problem, it also opens new perspectives about the relation between globular clusters and the halo of our Galaxy, and by extension of all populations with a high specific frequency of globular clusters, such as, e.g., giant elliptical galaxies. We review progress in this area, focusing on the most recent studies. Several points remain to be properly understood, in particular those concerning the nature of the polluters producing the abundance pattern in the clusters and the typical timescale, the range of cluster masses where this phenomenon is active, and the relation between globular clusters and other satellites of our Galaxy.Comment: In press (The Astronomy and Astrophysics Review

Links Between Hydrothermal Environments, Pyrophosphate, Na+, and Early Evolution

The discovery that photosynthetic bacterial membrane-bound inorganic pyrophosphatase (PPase) catalyzed light-induced phosphorylation of orthophosphate (Pi) to pyrophosphate (PPi) and the capability of PPi to drive energy requiring dark reactions supported PPi as a possible early alternative to ATP. Like the proton-pumping ATPase, the corresponding membrane-bound PPase also is a H+-pump, and like the Na+-pumping ATPase, it can be a Na+-pump, both in archaeal and bacterial membranes. We suggest that PPi and Na+ transport preceded ATP and H+ transport in association with geochemistry of the Earth at the time of the origin and early evolution of life. Life may have started in connection with early plate tectonic processes coupled to alkaline hydrothermal activity. A hydrothermal environment in which Na+ is abundant exists in sediment-starved subduction zones, like the Mariana forearc in the W Pacific Ocean. It is considered to mimic the Archean Earth. The forearc pore fluids have a pH up to 12.6, a Na+-concentration of 0.7 mol/kg seawater. PPi could have been formed during early subduction of oceanic lithosphere by dehydration of protonated orthophosphates. A key to PPi formation in these geological environments is a low local activity of water

Planck 2013 results. XXIX. Planck catalogue of Sunyaev-Zeldovich sources

We describe the all-sky Planck catalogue of clusters and cluster candidates derived from Sunyaev-Zeldovich (SZ) effect detections using the first 15.5 months of Planck satellite observations. The catalogue contains 1227 entries, making it over six times the size of the Planck Early SZ (ESZ) sample and the largest SZ-selected catalogue to date. It contains 861 confirmed clusters, of which 178 have been confirmed as clusters, mostly through follow-up observations, and a further 683 are previously-known clusters. The remaining 366 have the status of cluster candidates, and we divide them into three classes according to the quality of evidence that they are likely to be true clusters. The Planck SZ catalogue is the deepest all-sky cluster catalogue, with redshifts up to about one, and spans the broadest cluster mass range from (0.1 to 1.6) × 1015 M⊙. Confirmation of cluster candidates through comparison with existing surveys or cluster catalogues is extensively described, as is the statistical characterization of the catalogue in terms of completeness and statistical reliability. The outputs of the validation process are provided as additional information. This gives, in particular, an ensemble of 813 cluster redshifts, and for all these Planck clusters we also include a mass estimated from a newly-proposed SZ-mass proxy. A refined measure of the SZ Compton parameter for the clusters with X-ray counter-parts is provided, as is an X-ray flux for all the Planck clusters not previously detected in X-ray surveys.The development of Planck has been supported by: ESA; CNES and CNRS/INSU-IN2P3-INP (France); ASI, CNR, and INAF (Italy); NASA and DoE (USA); STFC and UKSA (UK); CSIC, MICINN and JA (Spain); Tekes, AoF and CSC (Finland); DLR and MPG (Germany); CSA (Canada); DTU Space (Denmark); SER/SSO (Switzerland); RCN (Norway); SFI (Ireland); FCT/MCTES (Portugal); and PRACE (EU).Peer Reviewe

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Meta-analysis of 375,000 individuals identifies 38 susceptibility loci for migraine

Migraine is a debilitating neurological disorder affecting around one in seven people worldwide, but its molecular mechanisms remain poorly understood. There is some debate about whether migraine is a disease of vascular dysfunction or a result of neuronal dysfunction with secondary vascular changes. Genome-wide association (GWA) studies have thus far identified 13 independent loci associated with migraine. To identify new susceptibility loci, we carried out a genetic study of migraine on 59,674 affected subjects and 316,078 controls from 22 GWA studies. We identified 44 independent single-nucleotide polymorphisms (SNPs) significantly associated with migraine risk (P < 5 × 10−8) that mapped to 38 distinct genomic loci, including 28 loci not previously reported and a locus that to our knowledge is the first to be identified on chromosome X. In subsequent computational analyses, the identified loci showed enrichment for genes expressed in vascular and smooth muscle tissues, consistent with a predominant theory of migraine that highlights vascular etiologies

Outcomes of a Multicenter Training Program in Robotic Pancreatoduodenectomy (LAELAPS-3)

OBJECTIVE: To assess feasibility and safety of a multicenter training program in robotic pancreatoduodenectomy (RPD) adhering to the IDEAL framework for implementation of surgical innovation. BACKGROUND: Good results for RPD have been reported from single center studies. However, data on feasibility and safety of implementation through a multicenter training program in RPD are lacking. METHODS: A multicenter training program in RPD was designed together with the University of Pittsburgh Medical Center, including an online video bank, robot simulation exercises, biotissue drills, and on-site proctoring. Benchmark patients were based on the criteria of Clavien. Outcomes were collected prospectively (March 2016-October 2019). Cumulative sum (CUSUM) analysis of operative time was performed to distinguish the first and second phase of the learning curve. Outcomes were compared between both phases of the learning curve. Trends in nationwide use of robotic and laparoscopic PD were assessed in the Dutch Pancreatic Cancer Audit. RESULTS: Overall, 275 RPD procedures were performed in seven centers by 15 trained surgeons. The recent benchmark criteria for low-risk PD were met by 125 (45.5%) patients. The conversion rate was 6.5% (n = 18) and median blood loss 250 ml (IQR 150-500). The rate of Clavien-Dindo grade ≥III complications was 44.4% (n = 122), postoperative pancreatic fistula (grade B/C) rate 23.6% (n = 65), 90-day complication-related mortality 2.5% (n = 7) and 90-day cancer-related mortality 2.2.% (n = 6). Median postoperative hospital stay was 12 days (IQR 8-20). In the subgroup of patients with pancreatic cancer (n = 80), the major complication rate was 31.3% and POPF rate was 10%. CUSUM analysis for operative time found a learning curve inflection point at 22 RPDs (IQR 10-35) with similar rates of Clavien-Dindo grade ≥III complications in the first and second phase (43.4% vs 43.8%, P = 0.956, respectively). During the study period the nationwide use of laparoscopic PD reduced from 15% to 1%, whereas the use of RPD increased from 0% to 25%. CONCLUSIONS: This multicenter RPD training program in centers with sufficient surgical volume was found to be feasible without a negative impact of the learning curve on clinical outcomes

Outcomes of a Multicenter Training Program in Robotic Pancreatoduodenectomy (LAELAPS-3)

OBJECTIVE: To assess feasibility and safety of a multicenter training program in robotic pancreatoduodenectomy (RPD) adhering to the IDEAL framework for implementation of surgical innovation. BACKGROUND: Good results for RPD have been reported from single center studies. However, data on feasibility and safety of implementation through a multicenter training program in RPD are lacking. METHODS: A multicenter training program in RPD was designed together with the University of Pittsburgh Medical Center, including an online video bank, robot simulation exercises, biotissue drills, and on-site proctoring. Benchmark patients were based on the criteria of Clavien. Outcomes were collected prospectively (March 2016-October 2019). Cumulative sum (CUSUM) analysis of operative time was performed to distinguish the first and second phase of the learning curve. Outcomes were compared between both phases of the learning curve. Trends in nationwide use of robotic and laparoscopic PD were assessed in the Dutch Pancreatic Cancer Audit. RESULTS: Overall, 275 RPD procedures were performed in seven centers by 15 trained surgeons. The recent benchmark criteria for low-risk PD were met by 125 (45.5%) patients. The conversion rate was 6.5% (n = 18) and median blood loss 250 ml (IQR 150-500). The rate of Clavien-Dindo grade ≥III complications was 44.4% (n = 122), postoperative pancreatic fistula (grade B/C) rate 23.6% (n = 65), 90-day complication-related mortality 2.5% (n = 7) and 90-day cancer-related mortality 2.2.% (n = 6). Median postoperative hospital stay was 12 days (IQR 8-20). In the subgroup of patients with pancreatic cancer (n = 80), the major complication rate was 31.3% and POPF rate was 10%. CUSUM analysis for operative time found a learning curve inflection point at 22 RPDs (IQR 10-35) with similar rates of Clavien-Dindo grade ≥III complications in the first and second phase (43.4% vs 43.8%, P = 0.956, respectively). During the study period the nationwide use of laparoscopic PD reduced from 15% to 1%, whereas the use of RPD increased from 0% to 25%. CONCLUSIONS: This multicenter RPD training program in centers with sufficient surgical volume was found to be feasible without a negative impact of the learning curve on clinical outcomes