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1.
Nature ; 568(7750): 55-60, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30890786

RESUMEN

NASA'S Origins, Spectral Interpretation, Resource Identification and Security-Regolith Explorer (OSIRIS-REx) spacecraft recently arrived at the near-Earth asteroid (101955) Bennu, a primitive body that represents the objects that may have brought prebiotic molecules and volatiles such as water to Earth1. Bennu is a low-albedo B-type asteroid2 that has been linked to organic-rich hydrated carbonaceous chondrites3. Such meteorites are altered by ejection from their parent body and contaminated by atmospheric entry and terrestrial microbes. Therefore, the primary mission objective is to return a sample of Bennu to Earth that is pristine-that is, not affected by these processes4. The OSIRIS-REx spacecraft carries a sophisticated suite of instruments to characterize Bennu's global properties, support the selection of a sampling site and document that site at a sub-centimetre scale5-11. Here we consider early OSIRIS-REx observations of Bennu to understand how the asteroid's properties compare to pre-encounter expectations and to assess the prospects for sample return. The bulk composition of Bennu appears to be hydrated and volatile-rich, as expected. However, in contrast to pre-encounter modelling of Bennu's thermal inertia12 and radar polarization ratios13-which indicated a generally smooth surface covered by centimetre-scale particles-resolved imaging reveals an unexpected surficial diversity. The albedo, texture, particle size and roughness are beyond the spacecraft design specifications. On the basis of our pre-encounter knowledge, we developed a sampling strategy to target 50-metre-diameter patches of loose regolith with grain sizes smaller than two centimetres4. We observe only a small number of apparently hazard-free regions, of the order of 5 to 20 metres in extent, the sampling of which poses a substantial challenge to mission success.


Asunto(s)
Medio Ambiente Extraterrestre/química , Planetas Menores , Vuelo Espacial , Exobiología , Origen de la Vida , Vuelo Espacial/instrumentación , Propiedades de Superficie
2.
Artículo en Inglés | MEDLINE | ID: mdl-38822578

RESUMEN

INTRODUCTION: Lichen sclerosus (LS) is an inflammatory skin disease affecting all ages. LS typically involves the anogenital site where it causes itching and soreness. It may lead to sexual and urinary dysfunction in females and males; however, it may be asymptomatic. First signs of LS are redness and oedema, typically followed by whitening of the genital skin; sometimes fissuring, scarring, shrinkage and fusion of structures may follow in its course. LS is associated with an increased risk of genital cancer. LS has a huge impact on the quality of life of affected patients, and it is important to raise more awareness of this not uncommon disease in order to diagnose and treat it early. OBJECTIVES: The guideline intends to provide guidance on the diagnostic of LS, highlight important aspects in the care of LS patients (part 1), generate recommendations and treatment algorithms (part 2) on topical, interventional and surgical therapy, based on the latest evidence, provide guidance in the management of LS patients during pregnancy, provide guidance for the follow-up of patients with LS and inform about new developments and potential research aspects. MATERIALS AND METHODS: The guideline was developed in accordance with the EuroGuiDerm Methods Manual v1.3 https://www.edf.one/de/home/Guidelines/EDF-EuroGuiDerm.html. The wording of the recommendations was standardized (as suggested by the GRADE Working Group). The guideline development group is comprised of 34 experts from 16 countries, including 5 patient representatives. RESULTS: Ultrapotent or potent topical corticosteroids in females and males, adults and children remain gold standard of care for genital LS; co-treatment with emollients is recommended. If standard treatment fails in males, a surgical intervention is recommended, complete circumcision may cure LS in males. UV light treatment is recommended for extragenital LS; however, there is limited scientific evidence. Topical calcineurin inhibitors are second line treatment. Laser treatment, using various wave lengths, is under investigation, and it can currently not be recommended for the treatment of LS. Treatment with biologics is only reported in single cases. CONCLUSIONS: LS has to be diagnosed and treated as early as possible in order to minimize sequelae like scarring and cancer development. Topical potent and ultrapotent corticosteroids are the gold standard of care; genital LS is often a lifelong disease and needs to be treated long-term.

3.
Artículo en Inglés | MEDLINE | ID: mdl-38822598

RESUMEN

INTRODUCTION: Lichen sclerosus (LS) is an inflammatory skin disease affecting all ages. LS typically involves the anogenital site where it causes itching and soreness; it may lead to sexual and urinary dysfunction in females and males; however, it may be asymptomatic. First signs of LS are usually a whitening of the genital skin, sometimes preceded by redness and oedema; fissuring, scarring, shrinkage and fusion of structures may follow in its course. LS is associated with an increased risk of genital cancer. LS has a huge impact on the quality of life of affected patients, and it is important to raise more awareness of this not uncommon disease in order to diagnose and treat it early. OBJECTIVES: The guideline intends to provide guidance on the diagnostic of LS (part 1), highlight important aspects in the care of LS patients, generate recommendations and treatment algorithms (part 2) on topical, interventional and surgical therapy, based on the latest evidence, provide guidance in the management of LS patients during pregnancy, provide guidance for the follow-up of patients with LS and inform about new developments and potential research aspects. MATERIALS AND METHODS: The guideline was developed in accordance with the EuroGuiDerm Methods Manual v1.3 https://www.edf.one/de/home/Guidelines/EDF-EuroGuiDerm.html. The wording of the recommendations was standardized (as suggested by the GRADE Working Group). The guideline development group is comprised of 34 experts from 16 countries, including 5 patient representatives. RESULTS: Ultrapotent or potent topical corticosteroids in females and males, adults and children remain gold standard of care for genital LS; co-treatment with emollients is recommended. If standard treatment fails in males, a surgical intervention is recommended, complete circumcision may cure LS in males. UV light treatment is recommended for extragenital LS; however, there is limited scientific evidence. Topical calcineurin inhibitors are second line treatment. Laser treatment, using various wave lengths, is under investigation, and it can currently not be recommended for the treatment of LS. Treatment with biologics is only reported in single cases. CONCLUSIONS: LS has to be diagnosed and treated as early as possible in order to minimize sequelae like scarring and cancer development. Topical potent and ultrapotent corticosteroids are the gold standard of care; genital LS is often a lifelong disease and needs to be treated long-term.

4.
Phys Rev Lett ; 128(5): 051101, 2022 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-35179913

RESUMEN

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19} cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with ß≳0.8 and up to ß∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

5.
Phys Rev Lett ; 129(15): 151801, 2022 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-36269964

RESUMEN

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{µ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9} eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

6.
Phys Rev Lett ; 129(1): 011804, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35841552

RESUMEN

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{µτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{µτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

7.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33929235

RESUMEN

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.

8.
J Appl Microbiol ; 131(5): 2552-2566, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33813786

RESUMEN

AIMS: The aim of this study was to isolate and characterize staphylococcal isolates from diabetic foot ulcers (DFU) in Jordanian patients. METHODS AND RESULTS: Selected aerobic pathogens recovered from DFU specimens and patients' nares with a focus on staphylococci were investigated. Antimicrobial susceptibilities and the prevalence of methicillin-resistant staphylococci (MRS) were determined. SCCmec types and toxigenic characteristics were analysed and spa typing was performed for methicillin-resistant Staphylococcus aureus (MRSA) isolates. The relationship between toxigenic characteristics of MRSA and the Wagner ulcer grading system was statistically analysed. A total number of 87 DFU patients were recruited for the study. The DFU cultures were polymicrobial. Members of the genus Staphylococcus were the most common among DFU-associated isolates found in 48·3% (n = 42) of all patients enrolled. Coagulase-negative staphylococci (CoNS) comprised 63·3% of staphylococci isolated from DFUs predominated by Staphylococcus epidermidis in both DFU (7·6%) and nares (39·2%). Staphylococcus aureus was isolated from DFUs and nares in 14·2 and 9·8%, respectively, while 93 and 70% of these isolates were MRSA. Most of MRSA carried SCCmec type IV (76·2%) while SCCmec elements were non-typeable in most methicillin resistant coagulase negative staphylococci (MR-CoNS) (61·9%). The most frequent MRSA spa type was t386 (23·8%). Most MRSA and MR-CoNS exhibited resistance towards aminoglycosides, fluoroquinolones and macrolides and susceptibility towards vancomycin, mupirocin and linezolid. No association was found between the possession of pvl, tst, sea and hlg toxins and Wagner ulcer grading system (P value >0·05). CONCLUSIONS: This analysis of Jordanian DFU culture demonstrated its polymicrobial nature with predominance of Staphylococcus sp. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first of its type to assess the microbiology of DFU among Jordanian patients. The results will help in the appropriate application of antimicrobial chemotherapy in the management of DFU.


Asunto(s)
Diabetes Mellitus , Pie Diabético , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Antibacterianos/farmacología , Pie Diabético/epidemiología , Humanos , Resistencia a la Meticilina , Staphylococcus aureus Resistente a Meticilina/genética , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/epidemiología , Staphylococcus/genética
9.
Stud Mycol ; 99: 100118, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34527085

RESUMEN

To date little is known about the genetic background that drives the production and diversification of secondary metabolites in the Hypoxylaceae. With the recent availability of high-quality genome sequences for 13 representative species and one relative (Xylaria hypoxylon) we attempted to survey the diversity of biosynthetic pathways in these organisms to investigate their true potential as secondary metabolite producers. Manual search strategies based on the accumulated knowledge on biosynthesis in fungi enabled us to identify 783 biosynthetic pathways across 14 studied species, the majority of which were arranged in biosynthetic gene clusters (BGC). The similarity of BGCs was analysed with the BiG-SCAPE engine which organised the BGCs into 375 gene cluster families (GCF). Only ten GCFs were conserved across all of these fungi indicating that speciation is accompanied by changes in secondary metabolism. From the known compounds produced by the family members some can be directly correlated with identified BGCs which is highlighted herein by the azaphilone, dihydroxynaphthalene, tropolone, cytochalasan, terrequinone, terphenyl and brasilane pathways giving insights into the evolution and diversification of those compound classes. Vice versa, products of various BGCs can be predicted through homology analysis with known pathways from other fungi as shown for the identified ergot alkaloid, trigazaphilone, curvupallide, viridicatumtoxin and swainsonine BGCs. However, the majority of BGCs had no obvious links to known products from the Hypoxylaceae or other well-studied biosynthetic pathways from fungi. These findings highlight that the number of known compounds strongly underrepresents the biosynthetic potential in these fungi and that a tremendous number of unidentified secondary metabolites is still hidden. Moreover, with increasing numbers of genomes for further Hypoxylaceae species becoming available, the likelihood of revealing new biosynthetic pathways that encode new, potentially useful compounds will significantly improve. Reaching a better understanding of the biology of these producers, and further development of genetic methods for their manipulation, will be crucial to access their treasures.

10.
Aesthetic Plast Surg ; 45(5): 2061-2074, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34145475

RESUMEN

INTRODUCTION: Reduction mammaplasty in patients with gigantomastia is challenging. The Double-Unit technique with a Superomedio-Central pedicle and inverted-T incision is the standard technique for reduction mammaplasty in our clinic. The aim of this study was to review our approach in cases with gigantomastia in comparison with the current literature. PATIENTS AND METHODS: From 01/2011 to 12/2017, we performed 831 reduction mammaplasties in 630 patients. The Double-Unit  Superomedio-Central  (DUS) pedicle and inverted-T incision was implemented as a standard procedure for gigantomastia. Patient demographics and the outcome parameters complication rate, patient satisfaction with the aesthetic result, nipple sensibility, and surgical revision rate were obtained and retrospectively analyzed. RESULTS: In 37 patients, 55 reduction mammaplasties were performed with more than 1000 g per breast. Mean resection weight was 1311 g on right side and 1289 g on left side. Mean age was 52.5 years, mean body mass index was 32.8 kg/m2, mean sternal-notch-to-nipple distance was 38.3 cm. A free NAC graft was necessary in four breasts. Overall complication rate was 14.5%; secondary surgical revision rate was 12.7%. 91% of the patients were "very satisfied" and "satisfied" with the aesthetic result. Nipple sensibility was rated "high" and "medium" in 83%. CONCLUSION: The Double-Unit technique with a Superomedio-Central pedicle and inverted-T incision is very effective to achieve volume reduction and aesthetically pleasing reproducible results with a low complication rate in cases with gigantomastia. LEVEL OF EVIDENCE: Level of Evidence This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Mamoplastia , Colgajos Quirúrgicos , Mama/anomalías , Mama/cirugía , Estética , Femenino , Humanos , Hipertrofia/cirugía , Persona de Mediana Edad , Pezones/cirugía , Estudios Retrospectivos , Medición de Riesgo , Resultado del Tratamiento
11.
Phys Rev Lett ; 125(14): 141801, 2020 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-33064514

RESUMEN

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100 eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5 eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

12.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-33016715

RESUMEN

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}.

13.
Phys Rev Lett ; 125(12): 121104, 2020 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-33016752

RESUMEN

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100 TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100 TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100 TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

14.
Phys Rev Lett ; 124(5): 051103, 2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-32083934

RESUMEN

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1 TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

15.
Clin Oral Investig ; 24(4): 1551-1560, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31414272

RESUMEN

OBJECTIVE: To assess the impact of various local pathologies on facial alveolar bone dimensions at tooth sites. MATERIALS AND METHODS: Cone-beam computed tomography images of 60 patients were analyzed. Healthy teeth and teeth with local pathologies (i.e., endodontically treated, periodontally diseased teeth, and teeth with periapical lesions) were included. The thickness of the facial alveolar bone was measured at five locations: (1) the bone crest (W0), (2) 25% (W25), (3) 50% (W50), (4) 75% (W75) of the distance from the bone crest to the root apex (A), and (5) in the A region (W100). The results were considered statistically significant at p < 0.0008 (adjustment according to the statistical correction for multiple testing). RESULTS: A total of 1174 teeth (707 healthy and 467 with the local pathologies) were assessed. Periodontally diseased maxillary premolars and anterior teeth in the mandible in the W0 position, as well as maxillary molars in the W25 position, tended to have a lower facial bone thickness when compared to the healthy teeth (0.68 mm vs. 0.84 mm, p = 0.008; 0.47 mm vs. 0.55 mm, p = 0.004; and 1.27 mm vs. 1.72 mm; p = 0.009, respectively). In contrast, the observed tendency pointed towards thicker facial bone wall for the periodontally diseased mandibular anterior teeth in the W50 position (0.74 vs. 0.52, p = 0.001). Healthy maxillary molars tended to display a thicker facial alveolar bone compared to the teeth with local pathologies in the W25, W50, and W75 positions (p = 0.001, p = 0.005, and p = 0.004, respectively). CONCLUSIONS: The present analysis has indicated that local pathologies are commonly associated with a compromised socket morphology. CLINICAL RELEVANCE: The facial bone thickness was particularly reduced at periodontally diseased teeth, which may challenge implant therapy.


Asunto(s)
Proceso Alveolar/diagnóstico por imagen , Tomografía Computarizada de Haz Cónico , Diente no Vital/diagnóstico por imagen , Diente/diagnóstico por imagen , Humanos , Maxilar , Enfermedades Periapicales , Enfermedades Periodontales , Estudios Retrospectivos
16.
Pediatr Surg Int ; 36(5): 563-568, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32232550

RESUMEN

PURPOSE: This study evaluates the capacity of ultrasonography as a diagnostic method to confirm the proper positioning of central venous catheter (CVC) when compared to the current gold standard, chest radiography (CR). METHODS: A prospective study was performed including children from 0 to 14 incomplete years, who underwent CVC placement between March and May 2018 at a teaching hospital in Brazil. A four-chamber view of the heart was performed with ultrasound during a rapid injection of saline solution to identify hyperechoic images and confirm the central position of the catheter. After that, a CR was performed. The diagnostic quality of ultrasound was evaluated based on accuracy, sensitivity, specificity, positive and negative predictive values. RESULTS: A total of 21 patients were analyzed. The mean age was 3.95 ± 4.01 years. The preferred puncture site was the right internal jugular vein (71.4%). Ultrasound accuracy to detect CVC positioning was 81%. Sensitivity, specificity and positive and negative predictive values were 33%, 100%, 100% and 79%, respectively. CONCLUSION: Ultrasound is a reliable method for detection of CVC positioning. Even so, with the four-chamber cardiac view, this method is unable to identify catheters inside heart chambers, therefore, needing to confirm the positioning with CR.


Asunto(s)
Cateterismo Venoso Central/métodos , Catéteres Venosos Centrales , Venas Yugulares/diagnóstico por imagen , Radiografía Torácica/métodos , Ultrasonografía/métodos , Adolescente , Venas Braquiocefálicas , Niño , Preescolar , Diseño de Equipo , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Prospectivos , Punciones
17.
Phys Rev Lett ; 122(5): 051102, 2019 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-30822017

RESUMEN

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5} erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52} erg. A hypothetical population of transient sources has to be more common than 10^{-5} Mpc^{-3} yr^{-1} (5×10^{-8} Mpc^{-3} yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

18.
Phys Rev Lett ; 120(7): 071801, 2018 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-29542976

RESUMEN

We present a measurement of the atmospheric neutrino oscillation parameters using three years of data from the IceCube Neutrino Observatory. The DeepCore infill array in the center of IceCube enables the detection and reconstruction of neutrinos produced by the interaction of cosmic rays in Earth's atmosphere at energies as low as ∼5 GeV. That energy threshold permits measurements of muon neutrino disappearance, over a range of baselines up to the diameter of the Earth, probing the same range of L/E_{ν} as long-baseline experiments but with substantially higher-energy neutrinos. This analysis uses neutrinos from the full sky with reconstructed energies from 5.6 to 56 GeV. We measure Δm_{32}^{2}=2.31_{-0.13}^{+0.11}×10^{-3} eV^{2} and sin^{2}θ_{23}=0.51_{-0.09}^{+0.07}, assuming normal neutrino mass ordering. These results are consistent with, and of similar precision to, those from accelerator- and reactor-based experiments.

19.
Ann Hematol ; 97(12): 2501-2508, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30121845

RESUMEN

Multidrug-resistant organisms (MDRO) have been developing as an emerging problem in allogeneic hematopoietic cell transplantation (HCT). Since no data are available on the course of MDRO colonization after HCT, we investigated in this retrospective, single-center study, persistence and clearance of MDRO after HCT. From June 2010 to December 2015, 121 consecutive HCT patients were included. Patients received a MDRO screening before conditioning as well as surveillance cultures after HCT. In MDRO-colonized patients, surveillance specimens were taken until MDRO were no longer detectable. Thirty-three patients (27%) were found to be colonized by at least one MDRO at any time point until day 100 post HCT. Day 100 (2-year) non-relapse mortality (NRM) and overall survival (OS) of MDRO-colonized (MDRO+) versus non-colonized (MDRO-) patients were essentially the same. NRM is 15% (21%) versus 15% (24%). Two-year OS is 60 versus 55% for MDRO+ versus MDRO- patients. Out of the 33 MDRO+ patients, 21 cleared the MDRO. Median time to non-detectability of MDRO was 6 months. In 12 patients, the MDRO persisted. There was a significant (p < 0.0001) survival difference between patients who cleared the MDRO versus those with MDRO persistence (2-year OS 80 vs 40%). Except for the length of antibiotic therapy as a potential risk factor for MDRO persistence after HCT, no other conventional factors could be identified. (a) colonization by MDRO per se had no negative impact on the outcome, (b) MDRO can be cleared by the majority of patients after allogeneic HCT, and (c) to increase the probability to clear MDRO, the use of antibiotics in MDRO+ patients should be reviewed critically.


Asunto(s)
Farmacorresistencia Bacteriana Múltiple , Farmacorresistencia Fúngica Múltiple , Trasplante de Células Madre Hematopoyéticas , Staphylococcus aureus Resistente a Meticilina , Infecciones por Pneumocystis , Pneumocystis carinii , Infecciones Estafilocócicas , Adulto , Anciano , Aloinjertos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Pneumocystis/tratamiento farmacológico , Infecciones por Pneumocystis/epidemiología , Infecciones por Pneumocystis/etiología , Estudios Retrospectivos , Factores de Riesgo , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/etiología
20.
Pathologe ; 39(4): 297-302, 2018 Jul.
Artículo en Alemán | MEDLINE | ID: mdl-29619508

RESUMEN

Access to well-characterized human biosamples is one of the most important prerequisites for modern biomedical research. Biobanks play a decisive role here, as they provide corresponding biosamples for planned analyses. Many interfering factors influencing the quality of biosamples have to be taken into account. In addition to logistical, ethical, and data protection aspects, preanalytical variables in the context of sample acquisition, storage, and processing should be mentioned in particular. In this paper, therefore, the most important preanalytical influencing factors are presented systematically and an overview of current national and international activities for the standardized recording of these factors is provided with the goal of being able to better understand their influence on results and to minimize them in the near future.


Asunto(s)
Bancos de Muestras Biológicas , Investigación Biomédica , Humanos , Manejo de Especímenes
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