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1.
Phys Rev Lett ; 132(2): 021001, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38277596

ABSTRACT

We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.

2.
Phys Rev Lett ; 130(6): 061001, 2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36827568

ABSTRACT

Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.

3.
Rev Esp Quimioter ; 35(3): 273-278, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35441836

ABSTRACT

OBJECTIVE: Hepatitis C virus (HCV) infection is a major public health problem that causes multiple comorbidities. People in prisons who inject intravenous drugs are at increased risk of HCV infection, and HCV infection is 15-fold more prevalent among prisoners compared with the community. The objective of this study was to analyse the clinical and epidemiological characteristics of residents of a Spanish prison with HCV infection who received antiviral treatment. METHODS: An observational, descriptive and retrospective study was performed. All patients with HCV infection diagnosed or followed up in an Infectious Diseases attached to a penitentiary were included in this study. RESULTS: Of 81 patients analysed, sixty-nine (83.1%) patients were male. The mean age was 50.1 (SD8.8) years, and 70% of the inmates had a history of injection drug use. Coinfection with HIV was detected in 30%. In up to 25% of the sample, there were data on chronic liver disease in the degree of liver cirrhosis. The diagnosis of HCV infection had been made more than 15 years earlier in 28% of those studied. Decompensations from liver disease, hepatocellular carcinoma, or hospital admissions were exceptional. Most of the inmates with HCV accepted treatment, and approximately 94% of the patients who completed treatment achieved a sustained virological response without interactions or complications of interest. CONCLUSIONS: The availability of direct-acting antivirals and their exceptional side effects constitute an opportunity to reduce the burden of HCV infection in Spain, particularly in these high-risk populations.


Subject(s)
Hepatitis C, Chronic , Hepatitis C , Antiviral Agents/therapeutic use , Female , Hepacivirus , Hepatitis C/complications , Hepatitis C/drug therapy , Hepatitis C/epidemiology , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/epidemiology , Humans , Male , Middle Aged , Prisons , Retrospective Studies
4.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Article in English | MEDLINE | ID: mdl-33929235

ABSTRACT

We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.

5.
Phys Rev Lett ; 126(9): 091101, 2021 Mar 05.
Article in English | MEDLINE | ID: mdl-33750144

ABSTRACT

We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. At 95% confidence, we report limits on (i) the mass of thermal relic warm DM, m_{WDM}>6.5 keV (free-streaming length, λ_{fs}≲10h^{-1} kpc), (ii) the velocity-independent DM-proton scattering cross section, σ_{0}<8.8×10^{-29} cm^{2} for a 100 MeV DM particle mass [DM-proton coupling, c_{p}≲(0.3 GeV)^{-2}], and (iii) the mass of fuzzy DM, m_{ϕ}>2.9×10^{-21} eV (de Broglie wavelength, λ_{dB}≲0.5 kpc). These constraints are complementary to other observational and laboratory constraints on DM properties.

6.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Article in English | MEDLINE | ID: mdl-33016715

ABSTRACT

We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.

7.
Phys Rev Lett ; 124(10): 101102, 2020 Mar 13.
Article in English | MEDLINE | ID: mdl-32216401

ABSTRACT

In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.

8.
Phys Rev Lett ; 123(18): 181301, 2019 Nov 01.
Article in English | MEDLINE | ID: mdl-31763885

ABSTRACT

We report the first detection of gravitational lensing due to galaxy clusters using only the polarization of the cosmic microwave background (CMB). The lensing signal is obtained using a new estimator that extracts the lensing dipole signature from stacked images formed by rotating the cluster-centered Stokes QU map cutouts along the direction of the locally measured background CMB polarization gradient. Using data from the SPTpol 500 deg^{2} survey at the locations of roughly 18 000 clusters with richness λ≥10 from the Dark Energy Survey (DES) Year-3 full galaxy cluster catalog, we detect lensing at 4.8σ. The mean stacked mass of the selected sample is found to be (1.43±0.40)×10^{14}M_{⊙} which is in good agreement with optical weak lensing based estimates using DES data and CMB-lensing based estimates using SPTpol temperature data. This measurement is a key first step for cluster cosmology with future low-noise CMB surveys, like CMB-S4, for which CMB polarization will be the primary channel for cluster lensing measurements.

9.
Rev Esp Quimioter ; 30(6): 391-396, 2017 Dec.
Article in English | MEDLINE | ID: mdl-29082727

ABSTRACT

Daptomycin is a cyclic lipopeptide active against multidrug-resistant Gram-positives, including methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus with reduced susceptibility to vancomycin. It is 4-8 fold as active as vancomycin against methicillin-susceptible S. aureus (MSSA) and MRSA, and retains most of this activity against S. aureus with reduced susceptibility to vancomycin. The mechanism of action of daptomycin is not fully understood. Daptomycin binds to the bacterial cytoplasmic membrane, leading to depolarization due to the loss of potassium ions from the cytoplasm. Daptomycin non-susceptibility is unusual in the clinical setting. Different mechanisms have been proposed to explain daptomycin-resistance, most of them associated to changes in composition, charge and fluidity of the cell wall. The mprF mutations, which lead to an increase in the lysyl-phosphatidyl glycerol production, and rpoB and rpoC mutations (rpo genes encode for bacterial RNA polymerase subunits) have been proposed as associated to daptomycin-resistance, but a number of mutations in other genes ( walK, cls, ggrA…) have been proposed.


Subject(s)
Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Daptomycin/pharmacology , Daptomycin/therapeutic use , Staphylococcal Infections/drug therapy , Staphylococcus aureus/drug effects , Drug Resistance, Bacterial/drug effects , Drug Resistance, Bacterial/genetics , Humans , Staphylococcal Infections/microbiology , Staphylococcus aureus/genetics
10.
Phys Rev Lett ; 117(19): 192001, 2016 Nov 04.
Article in English | MEDLINE | ID: mdl-27858429

ABSTRACT

Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.

11.
Phys Rev Lett ; 116(24): 241101, 2016 Jun 17.
Article in English | MEDLINE | ID: mdl-27367377

ABSTRACT

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8±0.7(stat)±6.7(syst) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.

12.
New Microbes New Infect ; 9: 47-9, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26862434

ABSTRACT

Small colony variants (SCV) are slow-growing subpopulations of bacteria usually associated with auxotrophism, causing persistent or recurrent infections. Enterococcus faecalis SCV have been seldom described, and only one case of Enterococcus faecium SCV has been reported, associated with sepsis in a leukaemia patient. Here we report the first case described of bacteraemia and endocarditis by SCV E. faecium in an immunocompetent patient.

13.
J Virol Methods ; 230: 18-23, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26784284

ABSTRACT

Hepatitis E virus (HEV) genotype 3 produces zoonotic infection associated with the consumption of infected animals. HEV infections can become chronic in immunocompromised (IC) patients. The viral genome has three well defined open reading frames (ORF1, ORF2 and ORF3) within which various domains and functions have been described. This paper (i) describes a new method of complete sequencing of the HEV coding region through overlapping PCR systems, (ii) establishes a consensus sequence and polymorphic positions (PP) for each domain, and (iii) analyzes the complete coding sequence of an IC patient. With regard to the consensus, a high percentage of PP was observed in protease (PP=19%) and the X domain (PP=22%) within ORF1, the N-terminal region of the S domain (PP=22%) in ORF2, and the P1 (PP=35%) and P2 (PP=25%) domains in ORF3. In contrast, the ORF1 Y, ORF2 S, ORF2 M and ORF3 D1 domains were conserved in the reference sequences (0.40, 1, 0.70 and 0% of PP, respectively). The sequence from the IC patient had more mutations in the RpRp (D1235G, Q1242R, S1454T, V1480I, I1502 V, K1511R, G1373 V, E1442D, V1693 M), the terminal ORF2 S- domain (F10L, S26T, G36S, S70P, A105 V, I113 V), the X domain (T938 M, T856 V, S898A) and the helicase (S1014N, S975T, Q1133 K).


Subject(s)
Genome, Viral , Genomics/methods , Hepatitis E virus/genetics , Hepatitis E/virology , Humans , Mutation , Open Reading Frames
16.
Actas Urol Esp ; 39(9): 582-7, 2015 Nov.
Article in English, Spanish | MEDLINE | ID: mdl-26255076

ABSTRACT

OBJECTIVE: Cryotherapy is a minimally invasive ablative technique that is considered an alternative to conventional surgery for preserving renal function in small renal tumors and in selected cases. We present our results from laparoscopic renal cryotherapy. MATERIAL AND METHOD: We retrospectively analyzed 17 renal tumors diagnosed in 16 patients treated with cryotherapy. The patients' mean age was 66 years (43-80). The mean tumor size was 1.8cm (0.7-3.7cm). Cryotherapy with double-freeze cycle was performed laparoscopically in all cases (10 by transperitoneal approach and 7 by retroperitoneal approach). RESULTS: Perioperative biopsies were performed on all patients and were positive for malignancy in 10 cases (59%). The mean stay was 2.8 days. The mean operative time was 162 minutes. Only 1 case reverted to open surgery due to bleeding. One patient required a blood transfusion in the immediate postoperative period. The majority of complications were Clavien-Dindo grades I and II. Some 76.5% of the patients had no complications. After a mean follow-up of 31 months (6-102), 1 patient died from nontumor-related causes, and 12 patients (75%) still show no evidence of local recurrence or progression. One patient had tumor persistence and therefore underwent partial nephrectomy at 6 months. One patient had a metachronous recurrence in the same kidney at 36 months, and another patient had a recurrence at 23 months. CONCLUSIONS: Laparoscopic renal cryotherapy is a safe and feasible technique and is a good alternative to surgery for selected renal tumors.


Subject(s)
Cryosurgery/methods , Kidney Neoplasms/surgery , Laparoscopy/methods , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Peritoneum , Retroperitoneal Space , Retrospective Studies
17.
Eur Phys J C Part Fields ; 75(6): 269, 2015.
Article in English | MEDLINE | ID: mdl-26120280

ABSTRACT

Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with [Formula: see text] eV by analyzing cosmic rays with energies above [Formula: see text] eV arriving within an angular separation of approximately 15[Formula: see text]. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.

18.
Clin Microbiol Infect ; 21(4): 370.e5-8, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25636386

ABSTRACT

We prospectively studied the prevalence of imported transmissible diseases in 373 immigrant children and adolescents coming from Sub-Saharan Africa, North Africa and Latin America to Salamanca, Spain. The most frequent transmissible diseases in this group were latent tuberculosis (12.7%), chronic hepatitis B virus infection (4.2%), hepatitis C virus infection (2.3%), syphilis (1.5%) and human T-lymphotropic virus type 1 or 2 infections (1.4%). A total of 24.2% of patients had serologic profiles suggesting past hepatitis B virus infection. Anti-human immunodeficiency virus antibodies were not detected in any subject. Largely asymptomatic immigrant children show a high prevalence of communicable diseases. Thus, infectious disease screenings are highly advisable in immigrant children coming from low-income countries.


Subject(s)
Communicable Diseases/epidemiology , Emigration and Immigration , Minors , Adolescent , Africa South of the Sahara , Africa, Northern , Asymptomatic Diseases/epidemiology , Child , Child, Preschool , Female , Humans , Infant , Latin America , Male , Prevalence , Prospective Studies , Spain/epidemiology
19.
J Clin Microbiol ; 52(1): 335-8, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24226916

ABSTRACT

We pretreated with SDS 71 urine samples with bacterial counts of >10(5) CFU/ml and matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) identification scores of <2, in order to minimize failure rates. Identification improved in 46.5% of samples, remained unchanged in 49.3%, and worsened in 4.2%. The improvement was more evident for Gram-negative (54.3%) than for Gram-positive (32%) bacteria.


Subject(s)
Bacteria/isolation & purification , Bacterial Infections/diagnosis , Microbiological Techniques/methods , Specimen Handling/methods , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Urinary Tract Infections/diagnosis , Urine/microbiology , Bacteria/classification , Detergents/pharmacology , Humans , Sodium Dodecyl Sulfate/pharmacology
20.
Phys Rev Lett ; 109(6): 062002, 2012 Aug 10.
Article in English | MEDLINE | ID: mdl-23006259

ABSTRACT

We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.

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