Large-order NSPT for lattice gauge theories with fermions:the plaquette in massless QCD

Numerical Stochastic Perturbation Theory (NSPT) allows for perturbative computations in quantum field theory. We present an implementation of NSPT that yields results for high orders in the perturbative expansion of lattice gauge theories coupled to fermions. The zero-momentum mode is removed by imposing twisted boundary conditions; in turn, twisted boundary conditions require us to introduce a smell degree of freedom in order to include fermions in the fundamental representation. As a first application, we compute the critical mass of two flavours of Wilson fermions up to order $O(\beta^{-7})$ in a ${\mathrm{SU}}(3)$ gauge theory. We also implement, for the first time, staggered fermions in NSPT. The residual chiral symmetry of staggered fermions protects the theory from an additive mass renormalisation. We compute the perturbative expansion of the plaquette with two flavours of massless staggered fermions up to order $O(\beta^{-35})$ in a ${\mathrm{SU}}(3)$ gauge theory, and investigate the renormalon behaviour of such series. We are able to subtract the power divergence in the Operator Product Expansion (OPE) for the plaquette and estimate the gluon condensate in massless QCD. Our results confirm that NSPT provides a viable way to probe systematically the asymptotic behaviour of perturbative series in QCD and, eventually, gauge theories with fermions in higher representations.Comment: 49 pages, 28 figures. Revised version, to be published in EPJC. Some references added, typos corrected, and improved discussion on finite-volume effect

First narrow-band search for continuous gravitational waves from known pulsars in advanced detector data

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signalto- noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars over a fraction of a hertz and several spin-down values. In this paper we describe a narrow-band search of 11 pulsars using data from Advanced LIGO’s first observing run. Although we have found several initial outliers, further studies show no significant evidence for the presence of a gravitational wave signal. Finally, we have placed upper limits on the signal strain amplitude lower than the spin-down limit for 5 of the 11 targets over the bands searched; in the case of J1813-1749 the spin-down limit has been beaten for the first time. For an additional 3 targets, the median upper limit across the search bands is below the spin-down limit. This is the most sensitive narrow-band search for continuous gravitational waves carried out so far

Prediction of preterm delivery in symptomatic women using PAMG‐1, fetal fibronectin and phIGFBP‐1 tests: systematic review and meta‐analysis

Objective To assess the accuracy of placental alpha microglobulin‐1 (PAMG‐1), fetal fibronectin (fFN) and phosphorylated insulin‐like growth factor‐binding protein‐1 (phIGFBP‐1) tests in predicting spontaneous preterm birth (sPTB) within 7 days of testing in women with symptoms of preterm labor, through a systematic review and meta‐analysis of the literature. The test performance of each biomarker was also assessed according to pretest probability of sPTB ≤ 7 days. Methods The Cochrane, MEDLINE, PubMed and ResearchGate bibliographic databases were searched from inception until October 2017. Cohort studies that reported on the predictive accuracy of PAMG‐1, fFN and phIGFBP‐1 for the prediction of sPTB within 7 days of testing in women with symptoms of preterm labor were included. Summary receiver–operating characteristics (ROC) curves and sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and positive (LR+) and negative (LR–) likelihood ratios were generated using indirect methods for the calculation of pooled effect sizes with a bivariate linear mixed model for the logit of sensitivity and specificity, with each diagnostic test as a covariate, as described by the Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy. Results Bivariate mixed model pooled sensitivity of PAMG‐1, fFN and phIGFBP‐1 for the prediction of sPTB ≤ 7 days was 76% (95% CI, 57–89%), 58% (95% CI, 47–68%) and 93% (95% CI, 88–96%), respectively; pooled specificity was 97% (95% CI, 95–98%), 84% (95% CI, 81–87%) and 76% (95% CI, 70–80%) respectively; pooled PPV was 76.3% (95% CI, 69–84%) (P < 0.05), 34.1% (95% CI, 29–39%) and 35.2% (95% CI, 31–40%), respectively; pooled NPV was 96.6% (95% CI, 94–99%), 93.3% (95% CI, 92–95%) and 98.7% (95% CI, 98–99%), respectively; pooled LR+ was 22.51 (95% CI, 15.09–33.60) (P < 0.05), 3.63 (95% CI, 2.93–4.50) and 3.80 (95% CI, 3.11–4.66), respectively; and pooled LR– was 0.24 (95% CI, 0.12–0.48) (P < 0.05), 0.50 (95% CI, 0.39–0.64) and 0.09 (95% CI, 0.05–0.16), respectively. The areas under the ROC curves for PAMG‐1, fFN and phIGFBP‐1 for sPTB ≤ 7 days were 0.961, 0.874 and 0.801, respectively. Conclusions In the prediction of sPTB within 7 days of testing in women with signs and symptoms of PTL, the PPV of PAMG‐1 was significantly higher than that of phIGFBP‐1 or fFN. Other diagnostic accuracy measures did not differ between the three biomarker tests. As prevalence affects the predictive performance of a diagnostic test, use of a highly specific assay for a lower‐prevalence syndrome such as sPTB may optimize management

Prevalence of normal weight obesity and its associated cardio-metabolic risk factors - Results from the baseline data of the Kerala Diabetes Prevention Program (KDPP)

BACKGROUND: Cardiometabolic disorders are frequently observed among those who have obesity as measured by body mass index (BMI). However, there is limited data available on the cardiometabolic profile of those who are non-obese by BMI but with a high body fat percentage (BFP), a phenotype frequently observed in the Indian population. We examined the prevalence of individuals with normal weight obesity (NWO) and the cardiometabolic profile of NWO individuals at high risk for type 2 diabetes(T2D) in a south Asian population. MATERIAL AND METHODS: In the Kerala Diabetes Prevention Program, individuals aged between 30 to 60 years were screened using the Indian Diabetes Risk Score(IDRS) in 60 rural communities in the Indian state of Kerala. We used data from the baseline survey of this trial for this analysis which included 1147 eligible high diabetes risk individuals(IDRS >60). NWO was defined as BMI within the normal range and a high BFP (as per Asia-pacific ethnicity based cut-off); Non-obese (NO) as normal BMI and BFP and overtly obese (OB) as BMI ≥25 kg/m2 irrespective of the BFP. Data on demographic, clinical and biochemical characteristics were collected using standardized questionnaires and protocols. Body fat percentage was assessed using TANITA body composition analyser (model SC330), based on bioelectrical impedance. RESULTS: The mean age of participants was 47.3 ± 7.5 years and 46% were women. The proportion with NWO was 32% (n = 364; 95% CI: 29.1 to 34.5%), NO was 17% (n = 200) and OB was 51% (n = 583). Among those with NWO, 19.7% had T2D, compared to 18.7% of those who were OB (p value = 0.45) and 8% with NO (p value = 0.003). Among those with NWO, mean systolic and diastolic blood pressure were 129 ± 20; 78 ± 12 mmHg, compared to 127 ± 17; 78±11 mmHg among those with OB (p value = 0.12;0.94) and 120 ± 16; 71±10 mmHg among with NO (p value<0.001; 0.001), respectively. A similar pattern of association was observed for LDL cholesterol and triglycerides. After adjusting for other risk factors, the odds of having diabetes (OR:2.72[95% CI:1.46-5.08]) and dyslipidemia (2.37[1.55-3.64]) was significantly more in individuals with NWO as compared to non-obese individuals. CONCLUSIONS: Almost one-third of this South Asian population, at high risk for T2D, had normal weight obesity. The significantly higher cardiometabolic risk associated with increased adiposity even in lower BMI individuals has important implications for recognition in clinical practice

Identifying metabolite markers for preterm birth in cervicovaginal fluid by magnetic resonance spectroscopy

Introduction Preterm birth (PTB) may be preceded by changes in the vaginal microflora and metabolite profiles. Objectives We sought to characterise the metabolite profile of cervicovaginal fluid (CVF) of pregnant women by 1H NMR spectroscopy, and assess their predictive value for PTB. Methods A pair of high-vaginal swabs was obtained from pregnant women with no evidence of clinical infection and grouped as follows: asymptomatic low risk (ALR) women with no previous history of PTB, assessed at 20–22 gestational weeks, g.w., n = 83; asymptomatic high risk (AHR) women with a previous history of PTB, assessed at both 20–22 g.w., n = 71, and 26–28 g.w., n = 58; and women presenting with symptoms of preterm labor (PTL) (SYM), assessed at 24–36 g.w., n = 65. Vaginal secretions were dissolved in phosphate buffered saline and scanned with a 9.4 T NMR spectrometer. Results Six metabolites (lactate, alanine, acetate, glutamine/glutamate, succinate and glucose) were analysed. In all study cohorts vaginal pH correlated with lactate integral (r = -0.62, p\0.0001). Lactate integrals were higher in the term ALR compared to the AHR (20–22 g.w.) women (p = 0.003). Acetate integrals were higher in the preterm versus term women for the AHR (20–22 g.w.) (p = 0.048) and SYM (p = 0.003) groups; and was predictive of PTB\37 g.w. (AUC 0.78; 95 % CI 0.61–0.95), and delivery within 2 weeks of the index assessment (AUC 0.84; 95 % CI 0.64–1) in the SYM women, whilst other metabolites were not. Conclusion High CVF acetate integral of women with symptoms of PTL appears predictive of preterm delivery, as well as delivery within 2 weeks of presentation

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

First measurement of the Hubble Constant from a Dark Standard Siren using the Dark Energy Survey Galaxies and the LIGO/Virgo Binary–Black-hole Merger GW170814

International audienceWe present a multi-messenger measurement of the Hubble constant H 0 using the binary–black-hole merger GW170814 as a standard siren, combined with a photometric redshift catalog from the Dark Energy Survey (DES). The luminosity distance is obtained from the gravitational wave signal detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO)/Virgo Collaboration (LVC) on 2017 August 14, and the redshift information is provided by the DES Year 3 data. Black hole mergers such as GW170814 are expected to lack bright electromagnetic emission to uniquely identify their host galaxies and build an object-by-object Hubble diagram. However, they are suitable for a statistical measurement, provided that a galaxy catalog of adequate depth and redshift completion is available. Here we present the first Hubble parameter measurement using a black hole merger. Our analysis results in , which is consistent with both SN Ia and cosmic microwave background measurements of the Hubble constant. The quoted 68% credible region comprises 60% of the uniform prior range [20, 140] km s−1 Mpc−1, and it depends on the assumed prior range. If we take a broader prior of [10, 220] km s−1 Mpc−1, we find (57% of the prior range). Although a weak constraint on the Hubble constant from a single event is expected using the dark siren method, a multifold increase in the LVC event rate is anticipated in the coming years and combinations of many sirens will lead to improved constraints on H 0

GW170104: Observation of a 50-Solar-Mass Binary Black Hole Coalescence at Redshift 0.2

We describe the observation of GW170104, a gravitational-wave signal produced by the coalescence of a pair of stellar-mass black holes. The signal was measured on January 4, 2017 at 10: 11: 58.6 UTC by the twin advanced detectors of the Laser Interferometer Gravitational-Wave Observatory during their second observing run, with a network signal-to-noise ratio of 13 and a false alarm rate less than 1 in 70 000 years. The inferred component black hole masses are 31.2(-6.0)(+8.4)M-circle dot and 19.4(-5.9)(+5.3)M(circle dot) (at the 90% credible level). The black hole spins are best constrained through measurement of the effective inspiral spin parameter, a mass-weighted combination of the spin components perpendicular to the orbital plane, chi(eff) = -0.12(-0.30)(+0.21) . This result implies that spin configurations with both component spins positively aligned with the orbital angular momentum are disfavored. The source luminosity distance is 880(-390)(+450) Mpc corresponding to a redshift of z = 0.18(-0.07)(+0.08) . We constrain the magnitude of modifications to the gravitational-wave dispersion relation and perform null tests of general relativity. Assuming that gravitons are dispersed in vacuum like massive particles, we bound the graviton mass to m(g) &lt;= 7.7 x 10(-23) eV/c(2). In all cases, we find that GW170104 is consistent with general relativity

REAL-WORLD ITALIAN EXPERIENCE OF POMALIDOMIDE IN RELAPSED-REFRACTORY MYELOMA: RETROSPECTIVE MULTICENTER STUDY BY THE RETE EMATOLOGICA PUGLIESE AND BASILICATA

Background: The POM+LoDEX combination was approved for patients with RRMM who have received at least two prior therapies including lenalidomide and bortezomib. Aims: We report here retrospective analysis of 94 patients with RRMM treated with POM+LoDEX as salvage therapy at 12 hematological centers in the Puglia and Basilicata Network to describe the outcomes and toxicities in a daily practice setting outside clinical trials. Methods: From January 2016 to September 2018, 94 patients (60 F and 34 M) were treated in our haematogical Institutions. Sixty-three patients of them (67%) had relapsed MM and 31 patients (33%) MM refractory to two or more previous treatment lines. The median age was 73 years (range 42–86). Twenty-four patients (23,3%) had EMD. Patients received a median 3 previous lines of therapy. The last treatment received was bortezomib-based regimens in 29% of patients, lenalidomide-based regimens in 50% of patients, and bendamustine containing regimen in 18% of patients. Results: The median number of cycles administered was 5 (range 1–27). The ORR was 51%. Higher ORR was recorded in the patient group with relapsed MM compared to those with refractory disease (p &lt; 0.05). There were no statistically significant differences in terms of response between patients who had received two or more previous lines of therapy (p NS) and between patients aged over or under 70 years (p 0.25). After median follow-up of 9.5 months, median TTP and median OS in the ITT population were respectively, 10 months (range 7–17) and 16 months (range 11–24). The median TTP was significantly longer in patients who achieved the haematological response (p &lt; 0.001) and in patients aged &gt;70 years (p 0.03). The median OS was significantly longer for fit patients (p 0.03). The “disease status’’, the “prior exposure to lenalidomide-based strategies’’, the “number of previous lines of therapy’’ did not influence the TTP and the OS. Multivariate analysis of median TTP identified the “high LDH levels’’ as negative variable (p &lt; 0.001) and the “age &gt;70 years’’ as positive prognostic factor (p &lt; 0.001). Multivariate analysis of median OS identified the “frailty score’’ and confirmed “high LDH levels’’ as statistically significant variables (p &lt; 0.001). Median TTNT was 30 months (range 18–30). Neutropenia was the most common hematologic adverse event and occurred in 32% of patients. The most frequent grade 3–4 non-haematologic toxicities were fatigue (6%) and infections (4%). Summary/Conclusion: POM+LoDEX resulted in a longer OS and TTP compared to data reported from clinical trials. This advantage was observed mainly in elderly patients and in those with haematologic response and the outcome benefit remained consistent regardless of number of prior and last therapy received. The good toxicity profile and the all-oral administration of POM+LoDEX make this combination a recommended therapeutic opportunity also in older patients and should be recommended mainly in patients living far from the hospital