Hipparion dispersal in Europe: magnetostratigraphic constraints from the Daroca area (Spain)

The Nombrevilla section in the Calatayud-Daroca basin (Central Spain) bears one of the best late Aragonian to early Vallesian large and small vertebrate fossil records in Europe, including important findings of the equid Hipparion. Magnetostratigraphic dating of the Nombrevilla section thus provides further age constraints on the timing of Hipparion dispersal in Europe, a bioevent which defines the base of the Vallesian mammal stage. Correlation of the Nombrevilla magnetic polarity stratigraphy to the geomagnetic polarity time scale is supported by the identification of the characteristic long normal chron C5n in the upper half of the section,... (Ver más) in association with early Vallesian (early late Miocene) fossils. The classic mammal fossil site Nombrevilla 1, recording the earliest occurrence of Hipparion, correlates to the lower third of chron C5n, and yields an interpolated age of about 10.7-10.8 Ma. This age is in agreement with magnetostratigraphic dating of earliest occurrences in Siwaliks of Pakistan and some 40Ar/39Ar ages of Mediterranean sites. The youngest pre-Hipparion large mammal fossil record corresponds to Nombrevilla 9, a site wich approximately correlates to chron C5r.1n, at about 11.1 Ma. This result is nearly in conflict with the data from the Vallès-Penedès, where a Hipparion bearing site is correlated to the same chron. In addition, Nombrevilla 9 yields a small mammal assemblage which corresponds to local zone H, a biozone wich was classically correlated to the lower Vallesian. This implies a diachrony of about 300 kyr between the lower boundary of zone H and the first occurrence of Hipparion (base of the Vallesian) in the Calatayud-Daroca basin. Correlation of the Aragonian levels of Nombrevilla 2, 3 and 4 is not yet certain and would require further downward extension of the magnetostratigraphy in a neighbouring section. Nevertheless, we can confidently say these localities are younger than 11.6 Ma

Aragonian stratigraphy reconsidered, and a re-evaluation of the middle Miocene mammal biochronology in Europe

The recently collected fauna of Armantes 1A in Chron C5Br of the Armantes section necessitates reinterpretation of the previous bio- and magnetostratigraphical correlations between the Armantes and Vargas sections (Calatayud-Daroca Basin, Central Spain) [W. Krijgsman, M. Garcés, C.G. Langereis, R. Daams, J. van Dam, A.J. van der Meulen, J. Agustí, L. Cabrera, A new chronology for the Middle to Late Miocene continental record in Spain, Earth Planet. Sci. Lett. 142 (1996) 367-380]. The long reversal in the Vargas section is now correlated to C5Br, instead of to C5Cr, on the basis of the biostratigraphical correlation of Armantes 1A to the faunas of Fuente Sierra 2 and 3 (in the Vargas section), which are situated in the basal part of the Middle Aragonian (MN5). This leads to the revised age of 16.0 Ma for the Early-Middle Aragonian (MN 4=5) boundary. Our age estimate of the MN5=6 boundary is maintained at ca. 13.75 Ma. The Vargas section is now considered to start in Chron C5Cn.2r and to end in C5Bn.1n. As a result of the revised correlation the duration of the time gap between the fossiliferous parts of Vargas and the younger Aragón section, previously estimated as ca. 1.5 Myr, is now reduced to less than 200,000 years. The tie points of the European mammal units (MN4-MN6) to the geomagnetic polarity time scale [F.F. Steininger, W.A. Berggren, D.V. Kent, R.L. Bernor, S. Sen, J. Agustí, Circum-Mediterranean Neogene (Miocene and Pliocene) marine-continental chronologic correlations of European mammal units, in: R.L Bernor, V. Fahlbusch, H.-W. Mittmann (Eds.), The Evolution of Western Eurasian Neogene Mammal Faunas, Columbia Univ. Press, New York, 1996, pp. 7-46] are evaluated. Our age estimates of the MN4=5 and MN5=6 boundaries are compatible with the new magnetostratigraphic calibration of middle Miocene mammal zones in the Swiss Molasse basin [O. Kempf, T. Bolliger, D. Kälin, B. Engesser, A. Matter, New magnetostratigraphic calibration of Early to Middle Miocene mammal biozones of the North Alpine foreland basin, in: J.-P. Aguilar, S. Legendre, J. Michaux (Eds.), Actes du Congrès BiochroM '97, Mém. Trav. E.P.H.E. 21 (1997) 547-562]. Ó 1999 Elsevier Science B.V. All rights reserved

BCS-Universal Ratios within the Van Hove Scenario

The central result of BCS theory are the Universal Ratios which do not depend on physical parameters of the superconductor under study. Several attempts have been made to introduce the van Hove Scenario within BCS theory but in none of them the Universal Ratios of conventional superconductivity appear to be a number independent of parameters. This fact prevents the precise definition of a deviation from the BCS value for a particular superconductor. This concept is at the basis of several applications of BCS theory in characterizing conventional superconductors. We define a system that constitutes a weak coupling limit that retains the essential features of the high-Tc oxides and which does not differ in any essential way from other models widely used in generalizations of BCS theory to high-Tc superconductors. The difference is that we found a natural way of dealing with the mathematics of the problem so as to get Universal Ratios in the same sense as in conventional superconductivity.Comment: 11 PAGES, NO FIGURES, REVTEX 3.

Non-radiologist-performed abdominal point-of-care ultrasonography in paediatrics — a scoping review

Background - Historically, US in the paediatric setting has mostly been the domain of radiologists. However, in the last decade, there has been an uptake of non-radiologist point-of-care US. Objective - To gain an overview of abdominal non-radiologist point-of-care US in paediatrics. Materials and methods - We conducted a scoping review regarding the uses of abdominal non-radiologist point-of-care US, quality of examinations and training, patient perspective, financial costs and legal consequences following the use of non-radiologist point-of-care US. We conducted an advanced search of the following databases: Medline, Embase and Web of Science Conference Proceedings. We included published original research studies describing abdominal non-radiologist point-of-care US in children. We limited studies to English-language articles from Western countries. Results - We found a total of 5,092 publications and selected 106 publications for inclusion: 39 studies and 51 case reports or case series on the state-of-art of abdominal non-radiologist point-of-care US, 14 on training of non-radiologists, and 1 each on possible harms following non-radiologist point-of-care US and patient satisfaction. According to included studies, non-radiologist point-of-care US is increasingly used, but no standardised training guidelines exist. We found no studies regarding the financial consequences of non-radiologist point-of-care US. Conclusion - This scoping review supports the further development of non-radiologist point-of-care US and underlines the need for consensus on who can do which examination after which level of training among US performers. More research is needed on training non-radiologists and on the costs-to-benefits of non-radiologist point-of-care US

Proximity effect and strong coupling superconductivity in nanostructures built with an STM

We present high resolution tunneling spectroscopy data at very low temperatures on superconducting nanostructures of lead built with an STM. By applying magnetic fields, superconductivity is restricted to length scales of the order of the coherence length. We measure the tunneling conductance and analyze the phonon structure and the low energy DOS. We demonstrate the influence of the geometry of the system on the magnetic field dependence of the tunneling density of states, which is gapless in a large range of fields. The behavior of the features in the tunneling conductance associated to phonon modes are explained within current models.Comment: 4 figures, 4 page

Approach to the Spanish continental Neogene synthesis and paleoclimatic interpretation

Integrated studies on Neogene geology have been scarce in Spain, but attemps to stratigraphic and sedimentological analysis of continental Tertiary basins have increased considerably lately. The large extent of Neogene basins in Spain, the good quality of the outcrops and the abundance of fossil provide an excellent basis for this kind of studies

Phonon-mediated anisotropic superconductivity in the Y and Lu nickel borocarbides

We present scanning tunneling spectroscopy and microscopy measurements at low temperatures in the borocarbide materials RNi2B2C (R=Y, Lu). The characteristic strong coupling structure due to the pairing interaction is unambiguously resolved in the superconducting density of states. It is located at the superconducting gap plus the energy corresponding to a phonon mode identified in previous neutron scattering experiments. These measurements also show that this mode is coupled to the electrons through a highly anisotropic electron-phonon interaction originated by a nesting feature of the Fermi surface. Our experiments, from which we can extract a large electron-phonon coupling parameter lambda (between 0.5 and 0.8), demonstrate that this anisotropic electron-phonon coupling has an essential contribution to the pairing interaction. The tunneling spectra show an anisotropic s-wave superconducting gap function.Comment: 5 pages, 3 figure

Severity of oEsophageal Anastomotic Leak in patients after oesophagectomy: the SEAL score

\ua9 The Author(s) 2022. Published by Oxford University Press on behalf of BJS Society Ltd. BACKGROUND: Anastomotic leak (AL) is a common but severe complication after oesophagectomy. It is unknown how to determine the severity of AL objectively at diagnosis. Determining leak severity may guide treatment decisions and improve future research. This study aimed to identify leak-related prognostic factors for mortality, and to develop a Severity of oEsophageal Anastomotic Leak (SEAL) score. METHODS: This international, retrospective cohort study in 71 centres worldwide included patients with AL after oesophagectomy between 2011 and 2019. The primary endpoint was 90-day mortality. Leak-related prognostic factors were identified after adjusting for confounders and were included in multivariable logistic regression to develop the SEAL score. Four classes of leak severity (mild, moderate, severe, and critical) were defined based on the risk of 90-day mortality, and the score was validated internally. RESULTS: Some 1509 patients with AL were included and the 90-day mortality rate was 11.7 per cent. Twelve leak-related prognostic factors were included in the SEAL score. The score showed good calibration and discrimination (c-index 0.77, 95 per cent c.i. 0.73 to 0.81). Higher classes of leak severity graded by the SEAL score were associated with a significant increase in duration of ICU stay, healing time, Comprehensive Complication Index score, and Esophagectomy Complications Consensus Group classification. CONCLUSION: The SEAL score grades leak severity into four classes by combining 12 leak-related predictors and can be used to the assess severity of AL after oesophagectomy

Treatment of anastomotic leak after oesophagectomy for oesophageal cancer:large, collaborative, observational TENTACLE cohort study

Background: Anastomotic leak is a severe complication after oesophagectomy. Anastomotic leak has diverse clinical manifestations and the optimal treatment strategy is unknown. The aim of this study was to assess the efficacy of treatment strategies for different manifestations of anastomotic leak after oesophagectomy. Methods: A retrospective cohort study was performed in 71 centres worldwide and included patients with anastomotic leak after oesophagectomy (2011-2019). Different primary treatment strategies were compared for three different anastomotic leak manifestations: interventional versus supportive-only treatment for local manifestations (that is no intrathoracic collections; well perfused conduit); drainage and defect closure versus drainage only for intrathoracic manifestations; and oesophageal diversion versus continuity-preserving treatment for conduit ischaemia/necrosis. The primary outcome was 90-day mortality. Propensity score matching was performed to adjust for confounders. Results: Of 1508 patients with anastomotic leak, 28.2 per cent (425 patients) had local manifestations, 36.3 per cent (548 patients) had intrathoracic manifestations, 9.6 per cent (145 patients) had conduit ischaemia/necrosis, 17.5 per cent (264 patients) were allocated after multiple imputation, and 8.4 per cent (126 patients) were excluded. After propensity score matching, no statistically significant differences in 90-day mortality were found regarding interventional versus supportive-only treatment for local manifestations (risk difference 3.2 per cent, 95 per cent c.i. -1.8 to 8.2 per cent), drainage and defect closure versus drainage only for intrathoracic manifestations (risk difference 5.8 per cent, 95 per cent c.i. -1.2 to 12.8 per cent), and oesophageal diversion versus continuity-preserving treatment for conduit ischaemia/necrosis (risk difference 0.1 per cent, 95 per cent c.i. -21.4 to 1.6 per cent). In general, less morbidity was found after less extensive primary treatment strategies. Conclusion: Less extensive primary treatment of anastomotic leak was associated with less morbidity. A less extensive primary treatment approach may potentially be considered for anastomotic leak. Future studies are needed to confirm current findings and guide optimal treatment of anastomotic leak after oesophagectomy.</p