227 research outputs found
A hot cocoon in the ultralong GRB 130925A: hints of a PopIII-like progenitor in a low density wind environment
GRB 130925A is a peculiar event characterized by an extremely long gamma-ray
duration (7 ks), as well as dramatic flaring in the X-rays for
20 ks. After this period, its X-ray afterglow shows an atypical soft
spectrum with photon index 4, as observed by Swift and Chandra,
until s, when XMM-Newton observations uncover a harder spectral
shape with 2.5, commonly observed in GRB afterglows. We find that
two distinct emission components are needed to explain the X-ray observations:
a thermal component, which dominates the X-ray emission for several weeks, and
a non-thermal component, consistent with a typical afterglow. A forward shock
model well describes the broadband (from radio to X-rays) afterglow spectrum at
various epochs. It requires an ambient medium with a very low density wind
profile, consistent with that expected from a low-metallicity blue supergiant
(BSG). The thermal component has a remarkably constant size and a total energy
consistent with those expected by a hot cocoon surrounding the relativistic
jet. We argue that the features observed in this GRB (its ultralong duration,
the thermal cocoon, and the low density wind environment) are associated with a
low metallicity BSG progenitor and, thus, should characterize the class of
ultralong GRBs.Comment: 6 pgs, 3 figs, fig1 revised, ApJL in pres
rates of latent tuberculosis infection using different diagnostica test
Background.The interferon−g−release assays (IGRA) are emerging as an attractive alternative to the tuberculin skin test (TST)
for the diagnosis of latent tuberculosis infection (LTBI).The absence of a gold standard for LTBI hampers the assessment of any
diagnostic test.
Methods.In a prospective study,229 patients (mean age 35.5±24.6 y) from different ward of the Hospital (Respiratory
Diseases,Dermatology, Rheumatology, Pediatrics, Infectious Diseases, Hematology and Transplant Unit) were simultaneously
tested for a suspect of either LTBI or active tuberculosis using all commercially available diagnostics: TST,QuantiFERON−TB
Gold (QFT−2G), QuantiFERON−TB Gold In−Tube(QFT−3G) and T−SPOT.TB(TS.TB).
Results. 42(18.3%),37(16.2%),59(25.8%) and 79(34.5%) patients were positive with TST,QFT−2G,QFT−3G and TS.TB,
respectively.TS.TB(p<0.001) and QFT−3G(p=0.016) provided more positive results than TST, while no difference was found for
TST and QFT−2G(p=0.53).All IGRA showed a good overall agreement (TS.TB vs QFT−2G,k=0.55; TS.TB vs
QFT−3G,k=0.72;QFT−2G vs QFT−3G, k=0.62). In 22 subjects (9.6%) QFT−3G was positive and QFT−2G negative.
Indeterminate results were more frequent with QFT−2G(18.3%) and QFT−3G (12.7%) than with TS.TB(1.3%,p<0.0001).
Conclusion. Rates of LTBI as detected by different diagnostic tests may have significant variations. Performances of various
IGRA formats were variable in this population
Cardiovascular Risk Profile in Subjects With Prediabetes and New-Onset Type 2 Diabetes Identified by HbA 1c According to American Diabetes Association Criteria
OBJECTIVE We investigated the cardiovascular risk profile in subjects with prediabetes and new-onset type 2 diabetes identified by glycated hemoglobin A 1c (HbA 1c ) according to the new American Diabetes Association criteria. RESEARCH DESIGN AND METHODS Arterial stiffness, intima-media thickness (IMT), soluble receptor for advanced glycation end products (sRAGEs), and oral glucose tolerance test (OGTT) were evaluated in 274 subjects without a previous history of diabetes. The subjects were stratified into three groups according to the HbA 1c levels. RESULTS The subjects with prediabetes ( n = 117, HbA 1c 5.7–6.4% [39–46 mmol/mol]) showed a higher augmentation (Aug), augmentation index (AugI), and IMT compared with those with lower HbA 1c ; however, these values were similar to those of subjects with HbA 1c >6.5% (48 mmol/mol). When we further analyzed the subjects with prediabetes but included only subjects with normal glucose tolerance (NT) in the analysis, AugI and IMT still remained significantly higher than their levels in control subjects with HbA 1c 1c , age, and sRAGE were significantly correlated with the IMT, whereas age and 1-h postload glucose were the major determinants of AugI. CONCLUSIONS Our data show that subjects with prediabetes according to HbA 1c , but with both NT according to the OGTT and normal fasting glycemia, have an altered IMT and AugI. These data suggest that a simple, reproducible, and less expensive marker such as HbA 1c may be better able to identify prediabetic subjects at high cardiovascular risk compared with fasting glycemia or OGTT alone
Spring honey bee losses in Italy
Honey bee poisoning incidents and monitoring schemes Background: During last years several cases of bee losses have been reported during the period of corn sowing in different European countries. In Italy an institutional system for bee losses survey does not exist and therefore some Italian regions decided to organise an official network to collect data and analyse dead bee samples. Results: Collected data indicate that the higher number of bee losses events occurred in intensively cultivated flat areas, located in the North of Italy, mainly during or after corn sowing. The chemical analyses of dead bees revealed the presence of three neonicotinoid residues: imidacloprid was found in 25.7% of the sample, thiamethoxam in 2.8%, clothianidin in 25.7%, both imidacloprid and thiamethoxam in 4.7%. The visual examination and the virological analyses excluded pathological causes. Conclusion: The spatial and temporal correlation between hive damages and corn sowing and the presence of residues of active ingredients used for seed dressing (imidacloprid, thiamethoxam and clothianidin) in almost half of the samples confirms the connection between spring mortality and the sowing of corn seed dressed with neonicotinoids. Keywords: honeybee mortality, neonicotinoids, seed dressing, corn sowing, dust dispersion.     Â
Searching for the radio remnants of short duration gamma-ray bursts
Neutron star mergers produce a substantial amount of fast-moving ejecta,
expanding outwardly for years after the merger. The interaction of these ejecta
with the surrounding medium may produce a weak isotropic radio remnant,
detectable in relatively nearby events. We use late-time radio observations of
short duration gamma-ray bursts (sGRBs) to constrain this model. Two samples of
events were studied: four sGRBs that are possibly in the local (<200 Mpc)
universe were selected to constrain the remnant non-thermal emission from the
sub-relativistic ejecta, whereas 17 sGRBs at cosmological distances were used
to constrain the presence of a proto-magnetar central engine, possibly
re-energezing the merger ejecta. We consider the case of GRB~170817A/GW170817,
and find that in this case the early radio emission may be quenched by the jet
blast-wave. In all cases, for ejecta mass range of M_ej \lesssim 10^{-2} (5 *
10^{-2}) M_sun, we can rule out very energetic merger ejecta E_ej \gtrsim 5 *
10^{52}(10^{53}) erg, thus excluding the presence of a powerful magnetar as a
merger remnant.Comment: 13 pages, 8 figures, 3 tables. Submitted to MNRA
Late-time radio observations of the short GRB200522A: constraints on the magnetar model
GRB200522A is a short duration gamma-ray burst (GRB) at redshift =0.554
characterized by a bright infrared counterpart. A possible, although not
unambiguous, interpretation of the observed emission is the onset of a luminous
kilonova powered by a rapidly rotating and highly-magnetized neutron star,
known as magnetar. A bright radio flare, arising from the interaction of the
kilonova ejecta with the surrounding medium, is a prediction of this model.
Whereas the available dataset remains open to multiple interpretations (e.g.
afterglow, r-process kilonova, magnetar-powered kilonova), long-term radio
monitoring of this burst may be key to discriminate between models. We present
our late-time upper limit on the radio emission of GRB200522A, carried out with
the Karl G. Jansky Very Large Array at 288 days after the burst. For kilonova
ejecta with energy , as expected for a
long-lived magnetar remnant, we can already rule out ejecta masses for the most likely range of circumburst
densities cm. Observations on timescales of
3-10 yr after the merger will probe larger ejecta masses up to , providing a robust test to the magnetar
scenario
Satisfaction with chronic obstructive pulmonary disease treatment: results from a multicenter, observational study
Background: Understanding the level of patients\u2019 satisfaction with treatment and its determinants have the potential to impact therapeutic management and clinical outcome in chronic conditions such as chronic obstructive pulmonary disease (COPD). Methods: A national, multicenter, longitudinal, observational study of COPD from 20 Italian pulmonary centers to explore patients\u2019 satisfaction to treatment [assessed by the Treatment Satisfaction Questionnaire, 9 items (TSQM-9)] and association with clinical parameters [including dyspnea score, COPD Assessment Test (CAT) score, exacerbation rate], adherence to treatment [Morisky Medication-Taking Adherence Scale (MMAS-4)], illness perception [evaluated by Brief Illness Perception Questionnaire (B-IPQ)] in a 1-year follow up. Results: A total of 401 COPD patients were enrolled [69.4% group B Global Initiative for COPD (GOLD), considering 366 patients with available GOLD 2017 classification at enrollment]. At enrollment, satisfaction with treatment was moderate, being TSQM-9 mean scores for effectiveness 64.2 [95% confidence interval (CI) 62.5\u201365.9], for convenience 75.8 (95% CI 74.2\u201377.3), and for global satisfaction 65.7 (95% CI 64.0\u201367.4). Global satisfaction was negatively associated with disease perception (\u3b2 = 120.4709, p < 0.0001), and grade of dyspnea (\u3b2 = 124.2564, p = 0.009). Satisfaction with treatment was lower in patients with poor compared with optimal adherence to treatment (\u3b2 = 124.5608, p = 0.002). Changes in inhalation regimens during follow up did not modify the satisfaction with treatment. Conclusions: The results of this real-life study showed that the patients\u2019 satisfaction with treatments is only moderate in COPD. A high grade of patients\u2019 satisfaction is associated mainly with a low perception of the disease, high adherence to treatment and lower level of dyspnea
Training and practice in bronchoscopy: A national survey in Italy
Training and practice in bronchoscopy. A national survey in Italy. N. Facciolongo, R. Piro, F. Menzella, M. Lusuardi, M. Salio, L. Lazzari Agli, M. Patelli. Background and Aim. Bronchoscopy is performed in a variety of different settings in Italy. The surveys conducted so far have highlighted the heterogeneity of the procedures and the frequent inability to adhere to the guidelines. The aim of this survey was to analyse procedures, training, and opinions of Italian respiratory physicians performing interventional bronchology in the clinical practice. Methods. The study was conducted retrospectively on 300 pulmonologists. From January to June 2008, these were invited to participate in an email survey to be sent out monthly to each participant for four consecutive months. Results. Two hundred and one respiratory physicians took part in the study, most of whom (83.5%) work in either Pulmonology or Interventional Pulmonology Units. The year before the survey, 21.2% of the participants had performed fewer than 100 examinations, 42.3% 100 to 300, and 36.6% more than 300 bronchoscopies; 53.9% were familiar with the international guidelines on the topic. Among the responders, 34.1% had received less than 6 months training, 55.3% considered further training in rigid bronchoscopy, laser procedures and thoracoscopy, invaluable for their professional activity. Adequate training for transbronchial needle aspirates, was reported by 49.6% of respondents. Conclusions. Our data show that interventional bronchoscopy procedures are regularly performed according to current recommendations by over half of the Italian Pulmonologists participating in our survey. The need for more comprehensive basic education and training was put forward by the majority of physicians
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