Gas phase Elemental abundances in Molecular cloudS (GEMS) VI. A sulphur journey across star-forming regions: study of thioformaldehyde emission

In the context of the IRAM 30m Large Program GEMS, we present a study of thioformaldehyde in several starless cores located in star-forming filaments of Taurus, Perseus, and Orion. We investigate the influence of the environmental conditions on the abundances of these molecules in the cores, and the effect of time evolution. We have modelled the observed lines of H2CS, HDCS, and D2CS using the radiative transfer code RADEX. We have also used the chemical code Nautilus to model the evolution of these species depending on the characteristics of the starless cores. We derive column densities and abundances for all the cores. We also derive deuterium fractionation ratios, Dfrac, to determine and compare the evolutionary stage between different parts of each star-forming region. Our results indicate that the north region of the B213 filament in Taurus is more evolved than the south, while the north-eastern part of Perseus presents an earlier evolutionary stage than the south-western zone. Model results also show that Dfrac decreases with the cosmic-ray ionisation rate, while it increases with density and with the degree of sulphur depletion. In particular, we only reproduce the observations when the initial sulphur abundance in the starless cores is at least one order of magnitude lower than the solar elemental sulphur abundance. The progressive increase in HDCS/H2CS and D2CS/H2CS with time makes these ratios powerful tools for deriving the chemical evolutionary stage of starless cores. However, they cannot be used to derive the temperature of these regions, since both ratios present a similar evolution at two different temperature ranges (7-11 K and 15-19 K). Regarding chemistry, (deuterated) thioformaldehyde is mainly formed through gas-phase reactions (double-replacement and neutral-neutral displacement reactions), while surface chemistry plays an important role as a destruction mechanism.Comment: 31 pages, 26 figure

Predictions from Heavy New Physics Interpretation of the Top Forward-Backward Asymmetry

We derive generic predictions at hadron colliders from the large forward-backward asymmetry observed at the Tevatron, assuming the latter arises from heavy new physics beyond the Standard Model. We use an effective field theory approach to characterize the associated unknown dynamics. By fitting the Tevatron t \bar t data we derive constraints on the form of the new physics. Furthermore, we show that heavy new physics explaining the Tevatron data generically enhances at high invariant masses both the top pair production cross section and the charge asymmetry at the LHC. This enhancement can be within the sensitivity of the 8 TeV run, such that the 2012 LHC data should be able to exclude a large class of models of heavy new physics or provide hints for its presence. The same new physics implies a contribution to the forward-backward asymmetry in bottom pair production at low invariant masses of order a permil at most.Comment: 11 pages, 6 figures. v2: added remarks on EFT validity range, dijet bounds and UV completions; matches published versio

Model prediction of subendocardial perfusion of the coronary circulation in the presence of an epicardial coronary artery stenosis

The subendocardium is most vulnerable to ischemia, which is ameliorated by relaxation during diastole and increased coronary pressure. Recent clinical techniques permit the measuring of subendocardial perfusion and it is therefore important to gain insight into how measurements depend on perfusion conditions of the heart. Using data from microsphere experiments a layered model of the myocardial wall was developed. Myocardial perfusion distribution during hyperemia was predicted for different degrees of coronary stenosis and at different levels of Diastolic Time Fraction (DTF). At the reference DTF, perfusion was rather evenly distributed over the layers and the effect of the stenosis was homogenous. However, at shorter or longer DTF, the subendocardium was the first or last to suffer from shortage of perfusion. It is therefore concluded that the possible occurrence of subendocardial ischemia at exercise is underestimated when heart rate is increased and DTF is lower

Surgical outcomes after neoadjuvant ablative dose radiation among patients with borderline resectable and locally advanced pancreas cancer from the multi-institutional phase 2 Stereotactic MR-Guided Adaptive Radiation Therapy (SMART) trial

Background: Acute grade 3+ toxicity was rare in the multi-institutional phase 2 stereotactic MR-guided on-table adaptive radiation therapy (SMART) trial (NCT03621644) for locally advanced and borderline resectable pancreatic cancer (LAPC/BRPC). Surgery may be considered after ablative SMART although the feasibility and safety of this is not well understood. Postoperative outcomes of the subset of patients in the SMART trial are examined here. Methods: Trial eligibility included BRPC or LAPC without metastases after a minimum of 3 months of induction chemotherapy. All patients received SMART prescribed to 50 Gy in 5 fractions using an integrated 0.35T MR-radiation therapy device equipped with cutting edge soft tissue tracking, automatic beam gating, and on-table adaptive replanning. Surgery was permitted after SMART, often after multi-disciplinary review. Perioperative details and postoperative outcomes, including morbidity, mortality, and overall survival (OS), were analyzed. Results: 136 patients across 13 sites were enrolled between 2019-2022. 44 patients (32.4%) had surgery after SMART (33 BRPC, 11 LAPC). Surgical procedures included pancreaticoduodenectomy (81.8%), distal pancreatectomy with splenectomy (9.1%), total pancreatectomy (6.8%), and distal pancreatectomy with celiac axis resection (2.3%). 52.3% required vascular resection/reconstruction, a majority of which were venous resections (65.2%), with a smaller proportion needing both venous/ arterial (21.7%), or arterial (13%). Surgery was performed after a mean 51.4 ± 52.8 days from SMART. Postoperative hospitalization was 10.5 ± 8.9 days. Nine patients (20.5%) had Clavien-Dindo complications of grade III or higher; 3 deaths resulted from post-pancreatectomy hemorrhage in patients who had portal vein resection. One-year OS in patients who had surgery versus no surgery after SMART was 66% vs. 43%, respectively. Conclusions: These are the first prospectively evaluated surgical outcomes after 5-fraction ablative SMART for BRPC/LAPC. The rate of surgery for BRPC compares favorably to radiated patients on the Alliance A021501 trial. Despite the use of ablative radiation dose and frequent need for vascular resection, the incidence of serious surgical complications was similar to what is reported after non-ablative radiation therapy. However, several deaths occurred after surgery and we therefore we urge caution when considering surgery after ablative radiation therapy. Further analysis of other variables such as the time between SMART and surgery, approaches to vascular resections, and discrete events such as delayed gastric emptying, operative duration, and post-operative pancreatic fistula are needed to better understand the surgical morbidity seen in these patients

Gas phase Elemental abundances in Molecular cloudS (GEMS) : II. On the quest for the sulphur reservoir in molecular clouds: the H2S case

Context. Sulphur is one of the most abundant elements in the Universe. Surprisingly, sulphuretted molecules are not as abundant as expected in the interstellar medium and the identity of the main sulphur reservoir is still an open question.Aims. Our goal is to investigate the H2S chemistry in dark clouds, as this stable molecule is a potential sulphur reservoir.Methods. Using millimeter observations of CS, SO, H2S, and their isotopologues, we determine the physical conditions and H2S abundances along the cores TMC 1-C, TMC 1-CP, and Barnard 1b. The gas-grain model NAUTILUS is used to model the sulphur chemistry and explore the impact of photo-desorption and chemical desorption on the H2S abundance.Results. Our modeling shows that chemical desorption is the main source of gas-phase H2S in dark cores. The measured H2S abundance can only be fitted if we assume that the chemical desorption rate decreases by more than a factor of 10 when n(H) > 2 x 10(4). This change in the desorption rate is consistent with the formation of thick H2O and CO ice mantles on grain surfaces. The observed SO and H2S abundances are in good agreement with our predictions adopting an undepleted value of the sulphur abundance. However, the CS abundance is overestimated by a factor of 5-10. Along the three cores, atomic S is predicted to be the main sulphur reservoir.Conclusions. The gaseous H2S abundance is well reproduced, assuming undepleted sulphur abundance and chemical desorption as the main source of H2S. The behavior of the observed H2S abundance suggests a changing desorption efficiency, which would probe the snowline in these cold cores. Our model, however, highly overestimates the observed gas-phase CS abundance. Given the uncertainty in the sulphur chemistry, we can only conclude that our data are consistent with a cosmic elemental S abundance with an uncertainty of a factor of 10.Peer reviewe

Meta-analyses of the sensitivity and specificity of ante-mortem and post-mortem diagnostic tests for bovine tuberculosis in the UK and Ireland

Publication history: Accepted - 26 February 2017; Published online - 6th March 2017.Bovine Tuberculosis (bTB) in cattle is a global health problem and eradication of the disease requires accu-rate estimates of diagnostic test performance to optimize their efficiency. The objective of this study was,through statistical meta-analyses, to obtain estimates of sensitivity (Se) and specificity (Sp), for 14 differ-ent ante-mortem and post-mortem diagnostic tests for bTB in cattle. Using data from a systematic reviewof the scientific literature (published 1934–2009) diagnostic Se and Sp were estimated using Bayesianlogistic regression models adjusting for confounding factors. Random effect terms were used to accountfor unexplained heterogeneity. Parameters in the models were implemented using Markov Chain MonteCarlo (MCMC), and posterior distributions for the diagnostic parameters with adjustment for covariates(confounding factors) were obtained using the inverse logit function. Estimates for Se and/or Sp of thetuberculin skin tests and the IFN- blood test were compared with estimates published 2010–2015.Median Se for the single intradermal comparative cervical tuberculin skin (SICCT) test (standard inter-pretation) was 0.50 and Bayesian credible intervals (CrI) were wide (95% CrI 0.26, 0.78). Median Sp forthe SICCT test was 1.00 (95% CrI 0.99, 1.00). Estimates for the IFN- blood test Bovine Purified ProteinDerivative (PPD)-Avian PPD and Early Secreted Antigen target 6 and Culture Filtrate Protein 10 (ESAT-6/CFP10) ESAT6/CFP10 were 0.67 (95% CrI 0.49, 0.82) and 0.78 (95% CrI 0.60, 0.90) respectively for Se,and 0.98 (95% CrI 0.96, 0.99) and 0.99 (95% CrI 0.99, 1.00) for Sp. The study provides an overview of theaccuracy of a range of contemporary diagnostic tests for bTB in cattle. Better understanding of diagnostictest performance is essential for the design of effective control strategies and their evaluation.The SE3238 project “Meta-analysis of diagnostic tests and modelling to identify appropriate testing strategies to reduce M. bovis infection in GB herds” was funded by the UK Department for Envi-ronment, Food and Rural Affairs (Defra)

Gas phase Elemental abundances in Molecular cloudS (GEMS) : III. Unlocking the CS chemistry: the CS plus O reaction

Context. Carbon monosulphide (CS) is among the most abundant gas-phase S-bearing molecules in cold dark molecular clouds. It is easily observable with several transitions in the millimeter wavelength range, and has been widely used as a tracer of the gas density in the interstellar medium in our Galaxy and external galaxies. However, chemical models fail to account for the observed CS abundances when assuming the cosmic value for the elemental abundance of sulfur. Aims. The CS+O -> CO + S reaction has been proposed as a relevant CS destruction mechanism at low temperatures, and could explain the discrepancy between models and observations. Its reaction rate has been experimentally measured at temperatures of 150-400 K, but the extrapolation to lower temperatures is doubtful. Our goal is to calculate the CS+O reaction rate at temperatures Methods. We performed ab initio calculations to obtain the three lowest potential energy surfaces (PES) of the CS+O system. These PESs are used to study the reaction dynamics, using several methods (classical, quantum, and semiclassical) to eventually calculate the CS + O thermal reaction rates. In order to check the accuracy of our calculations, we compare the results of our theoretical calculations for T similar to 150-400 K with those obtained in the laboratory. Results. Our detailed theoretical study on the CS+O reaction, which is in agreement with the experimental data obtained at 150-400 K, demonstrates the reliability of our approach. After a careful analysis at lower temperatures, we find that the rate constant at 10 K is negligible, below 10(-15) cm(3) s(-1), which is consistent with the extrapolation of experimental data using the Arrhenius expression. Conclusions. We use the updated chemical network to model the sulfur chemistry in Taurus Molecular Cloud 1 (TMC 1) based on molecular abundances determined from Gas phase Elemental abundances in Molecular CloudS (GEMS) project observations. In our model, we take into account the expected decrease of the cosmic ray ionization rate, zeta(H2), along the cloud. The abundance of CS is still overestimated when assuming the cosmic value for the sulfur abundance.Peer reviewe

Heavy quarkonium: progress, puzzles, and opportunities

A golden age for heavy quarkonium physics dawned a decade ago, initiated by the confluence of exciting advances in quantum chromodynamics (QCD) and an explosion of related experimental activity. The early years of this period were chronicled in the Quarkonium Working Group (QWG) CERN Yellow Report (YR) in 2004, which presented a comprehensive review of the status of the field at that time and provided specific recommendations for further progress. However, the broad spectrum of subsequent breakthroughs, surprises, and continuing puzzles could only be partially anticipated. Since the release of the YR, the BESII program concluded only to give birth to BESIII; the $B$-factories and CLEO-c flourished; quarkonium production and polarization measurements at HERA and the Tevatron matured; and heavy-ion collisions at RHIC have opened a window on the deconfinement regime. All these experiments leave legacies of quality, precision, and unsolved mysteries for quarkonium physics, and therefore beg for continuing investigations. The plethora of newly-found quarkonium-like states unleashed a flood of theoretical investigations into new forms of matter such as quark-gluon hybrids, mesonic molecules, and tetraquarks. Measurements of the spectroscopy, decays, production, and in-medium behavior of c\bar{c}, b\bar{b}, and b\bar{c} bound states have been shown to validate some theoretical approaches to QCD and highlight lack of quantitative success for others. The intriguing details of quarkonium suppression in heavy-ion collisions that have emerged from RHIC have elevated the importance of separating hot- and cold-nuclear-matter effects in quark-gluon plasma studies. This review systematically addresses all these matters and concludes by prioritizing directions for ongoing and future efforts.Comment: 182 pages, 112 figures. Editors: N. Brambilla, S. Eidelman, B. K. Heltsley, R. Vogt. Section Coordinators: G. T. Bodwin, E. Eichten, A. D. Frawley, A. B. Meyer, R. E. Mitchell, V. Papadimitriou, P. Petreczky, A. A. Petrov, P. Robbe, A. Vair