Probing the existence of ultralight bosons with a single gravitational-wave measurement

Light bosons, proposed as a possible solution to various problems in fundamental physics and cosmology , include a broad class of candidates for physics beyond the standard model, such as dilatons and moduli , wave dark matter and axion-like particles. If light bosons exist in nature, they will spontaneously form ‘clouds’ by extracting rotational energy from rotating massive black holes through superradiance, a classical wave amplification process that has been studied for decades. The superradiant growth of the cloud sets the geometry of the final black hole, and the black hole geometry determines the shape of the cloud. Hence, both the black hole geometry and the cloud encode information about the light boson. For this reason, measurements of the gravitational field of the black hole/cloud system (as encoded in gravitational waves) are over-determined. We show that a single gravitational-wave measurement can be used to verify the existence of light bosons by model selection, rule out alternative explanations for the signal, and measure the boson mass. Such measurements can be done generically for bosons in the mass range [10 −16.5 , 10 −14 ] eV using observations of extreme mass-ratio inspirals (EMRIs) by the forthcoming Laser Interferometer Space Antenna (LISA)

Observational signatures of microlensing in gravitational waves at LIGO/Virgo frequencies

Microlenses with typical stellar masses (a few ${\rm M}_{\odot}$) have traditionally been disregarded as potential sources of gravitational lensing effects at LIGO/Virgo frequencies, since the time delays are often much smaller than the inverse of the frequencies probed by LIGO/Virgo, resulting in negligible interference effects at LIGO/Virgo frequencies. While this is true for isolated microlenses in this mass regime, we show how, under certain circumstances and for realistic scenarios, a population of microlenses (for instance stars and remnants from a galaxy halo or from the intracluster medium) embedded in a macromodel potential (galaxy or cluster) can conspire together to produce time delays of order one millisecond which would produce significant interference distortions in the observed strains. At sufficiently large magnification factors (of several hundred), microlensing effects should be common in gravitationally lensed gravitational waves. We explore the regime where the predicted signal falls in the frequency range probed by LIGO/Virgo. We find that stellar mass microlenses, permeating the lens plane, and near critical curves, can introduce interference distortions in strongly lensed gravitational waves. For those lensed events with negative parity, (or saddle points, never studied before in the context of gravitational waves), and that take place near caustics of macromodels, they are more likely to produce measurable interference effects at LIGO/Virgo frequencies. This is the first study that explores the effect of a realistic population of microlenses, plus a macromodel, on strongly lensed gravitational waves.Comment: 16 page

Antimicrobial resistance of Escherichia coli isolates from outpatient urinary tract infections in women in six European countries including Russia

Objectives In the Northern Dimension Antibiotic Resistance Study (NoDARS), Finland, Germany, Latvia, Poland, Russia and Sweden collected urine samples from outpatient women (aged 18–65 years) with symptoms of uncomplicated urinary tract infection (UTI) to investigate the levels of antimicrobial resistance (AMR) among Escherichia coli isolates. Methods A total of 775 E. coli isolates from 1280 clinical urine samples were collected from October 2015 to January 2017. Antimicrobial susceptibility testing was performed and the results were interpreted according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. Results Overall AMR rates to the commonly used antibiotics nitrofurantoin, fosfomycin and mecillinam (except for Germany that was missing a result for mecillinam) were 1.2%, 1.3% and 4.1%, respectively. The highest overall resistance rates were determined for ampicillin (39.6%), trimethoprim (23.8%), trimethoprim/sulfamethoxazole (22.4%), amoxicillin/clavulanic acid (16.7%) and ciprofloxacin (15.1%), varying significantly between countries. The rate of extended-spectrum β-lactamase (ESBL) production was 8.7%. None of the isolates showed resistance to meropenem. Conclusions In most cases, low AMR rates were detected against the first-line antibiotics recommended in national UTI treatment guidelines, giving support to their future use. These results also support the European Association of Urology guidelines stating that nitrofurantoin, fosfomycin and mecillinam are viable treatment options for uncomplicated UTI.Peer Reviewe

Search for gravitational lensing signatures in LIGO-Virgo binary black hole events

We search for signatures of gravitational lensing in the binary black hole events detected by Advanced LIGO and Virgo during their first two observational runs. In particular, we look for three effects: 1) evidence of lensing magnification in the individual signals due to galaxy lenses, 2) evidence of multiple images due to strong lensing by galaxies, 3) evidence of wave optics effects due to point-mass lenses. We find no compelling evidence of any of these signatures in the observed gravitational wave signals. However, as the sensitivities of gravitational wave detectors improve in the future, detecting lensed events may become quite likely

Prevalence of pneumococcal nasopharyngeal colonization and serotypes circulating in Cameroonian children after the 13-valent pneumococcal conjugate vaccine introduction

BackgroundStreptococcus pneumoniae remains a major contributor to childhood infections and deaths globally. In Cameroon, the 13-valent pneumococcal conjugate vaccine (PCV13) was introduced in July 2011, using a 3-dose Expanded programme on immunization (EPI) schedule administered to infants at 6, 10 and 14 weeks of age. To evaluate PCV13 effects, we assessed pneumococcal nasopharyngeal colonization and serotype distribution among Cameroonian children after PCV13 introduction.MethodsNasopharyngeal (NP) swabs were collected from eligible children aged 24–36 months in two cross-sectional surveys conducted from March to July: in 2013 (PCV13-unvaccinated), and in 2015 (PCV13-vaccinated). Using a systematic World Health Organization (WHO) cluster coverage sampling technique in 40 communities, NP swabs collected were processed following WHO recommendations. Standard bacterial culture techniques were used for the isolation of S. pneumoniae from gentamicin-blood agar plates and identification using optochin susceptibility testing. Serotyping was performed using sequential multiplex polymerase chain reaction, supplemented with Quellung test.ResultsAmong the PCV13-vaccinated children, overall pneumococcal carriage prevalence was 61.8% (426/689) and PCV13 vaccine-type carriage prevalence was 18.0% (123/689). Eleven out of the 13 vaccine serotypes were detected in the vaccinated children. The most common serotypes were 19F (4.5%, 31/689) and 15B/C (7.3%, 50/689).ConclusionIn Cameroon, four years after infant vaccination nearly all of the PCV13-serotypes continued to circulate in the population. This suggests that the direct and indirect effects of the vaccination programme have not resulted in expected low levels of vaccine-type transmission. Continuous monitoring is needed to assess the long term effects of the PCV13 on nasopharyngeal carriage and disease.</div

Follow-up analyses to the O3 LIGO-Virgo-KAGRA lensing searches

Along their path from source to observer, gravitational waves may be gravitationally lensed by massive objects leading to distortion in the signals. Searches for these distortions amongst the observed signals from the current detector network have already been carried out, though there have as yet been no confident detections. However, predictions of the observation rate of lensing suggest detection in the future is a realistic possibility. Therefore, preparations need to be made to thoroughly investigate the candidate lensed signals. In this work, we present some follow-up analyses that could be applied to assess the significance of such events and ascertain what information may be extracted about the lens-source system by applying these analyses to a number of O3 candidate events, even if these signals did not yield a high significance for any of the lensing hypotheses. These analyses cover the strong lensing, millilensing, and microlensing regimes. Applying these additional analyses does not lead to any additional evidence for lensing in the candidates that have been examined. However, it does provide important insight into potential avenues to deal with high-significance candidates in future observations

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

Nasopharyngeal Bacterial Colonization and Gene Polymorphisms of Mannose-Binding Lectin and Toll-Like Receptors 2 and 4 in Infants

BACKGROUND: Human nasopharynx is often colonized by potentially pathogenic bacteria. Gene polymorphisms in mannose-binding lectin (MBL), toll-like receptor (TLR) 2 and TLR4 have been reported. The present study aimed to investigate possible association between nasopharyngeal bacterial colonization and gene polymorphisms of MBL, TLR2 and TLR4 in healthy infants. METHODOLOGY/PRINCIPAL FINDINGS: From August 2008 to June 2010, 489 nasopharyngeal swabs and 412 blood samples were taken from 3-month-old healthy Finnish infants. Semi-quantitative culture was performed and pyrosequencing was used for detection of polymorphisms in MBL structural gene at codons 52, 54, and 57, TLR2 Arg753Gln and TLR4 Asp299Gly. Fifty-nine percent of subjects were culture positive for at least one of the four species: 11% for Streptococcus pneumoniae, 23% for Moraxella catarrhalis, 1% for Haemophilus influenzae and 25% for Staphylococcus aureus. Thirty-two percent of subjects had variant types in MBL, 5% had polymorphism of TLR2, and 18% had polymorphism of TLR4. Colonization rates of S. pneumoniae and S. aureus were significantly higher in infants with variant types of MBL than those with wild type (p = .011 and p = .024). Colonization rates of S. aureus and M. catarrhalis were significantly higher in infants with polymorphisms of TLR2 and of TLR4 than those without (p = .027 and p = .002). CONCLUSIONS: Our study suggests that there is an association between nasopharyngeal bacterial colonization and genetic variation of MBL, TLR2 and TLR4 in young infants. This finding supports a role for these genetic variations in susceptibility of children to respiratory infections

HFE C282Y and H63D in adults with malignancies in a community medical oncology practice

BACKGROUND: We sought to compare frequencies of HFE C282Y and H63D alleles and associated odds ratios (OR) in 100 consecutive unrelated white adults with malignancy to those in 318 controls. METHODS: Data from patients with more than one malignancy were analyzed according to each primary malignancy. For the present study, OR ≥2.0 or ≤0.5 was defined to be increased or decreased, respectively. RESULTS: There were 110 primary malignancies (52 hematologic neoplasms, 58 carcinomas) in the 100 adult patients. Allele frequencies were similar in patients and controls (C282Y: 0.0850 vs. 0.0896, respectively (OR = 0.9); H63D: 0.1400 vs. 0.1447, respectively (OR = 0.9)). Two patients had hemochromatosis and C282Y homozygosity. With C282Y, increased OR occurred in non-Hodgkin lymphoma, myeloproliferative disorders, and adenocarcinoma of prostate (2.0, 2.8, and 3.4, respectively); OR was decreased in myelodysplasia (0.4). With H63D, increased OR occurred in myeloproliferative disorders and adenocarcinomas of breast and prostate (2.4, 2.0, and 2.0, respectively); OR was decreased in non-Hodgkin lymphoma and B-chronic lymphocytic leukemia (0.5 and 0.4, respectively). CONCLUSIONS: In 100 consecutive adults with malignancy evaluated in a community medical oncology practice, frequencies of HFE C282Y or H63D were similar to those in the general population. This suggests that C282Y or H63D is not associated with an overall increase in cancer risk. However, odds ratios computed in the present study suggest that increased (or decreased) risk for developing specific types of malignancy may be associated with the inheritance of HFE C282Y or H63D. Study of more patients with these specific types of malignancies is needed to determine if trends described herein would remain and yield significant differences