Baryon Acoustic Oscillations (BAOs) provide a 'standard ruler' of known physical length, making it one of the most promising probes of the nature of dark energy (DE). The detection of BAOs as an ...excess of power in the galaxy distribution at a certain scale requires measuring galaxy positions and redshifts. 'Transversal' (or 'angular') BAOs measure the angular size of this scale projected in the sky and provide information about the angular distance. 'Line-of-sight' (or 'radial') BAOs require very precise redshifts, but provide a direct measurement of the Hubble parameter at different redshifts, a more sensitive probe of DE. The main goal of this paper is to show that it is possible to obtain photometric redshifts with enough precision ( sigma z ) to measure BAOs along the line of sight. There is a fundamental limitation as to how much one can improve the BAO measurement by reducing sigma z . We show that sigma z ~ 0.003(1 + z) is sufficient: a much better precision will produce an oversampling of the BAO peak without a significant improvement on its detection, while a much worse precision will result in the effective loss of the radial information. This precision in redshift can be achieved for bright, red galaxies, featuring a prominent 4000 A break, by using a filter system comprising about 40 filters, each with a width close to 100 A, covering the wavelength range from ~4000 to ~8000 A, supplemented by two broad-band filters similar to the Sloan Digital Sky Survey u and z bands. We describe the practical implementation of this idea, a new galaxy survey project, PAU16Physics of the Accelerating Universe (PAU): http://www.ice.cat/pau., to be carried out with a telescope/camera combination with an etendue about 20 m2 deg2, equivalent to a 2 m telescope equipped with a 6 deg2 field of view camera, and covering 8000 deg2 in the sky in four years. We expect to measure positions and redshifts for over 14 million red, early-type galaxies with L > L and iAB 22.5 in the redshift interval 0.1 < z < 0.9, with a precision sigma z < 0.003(1 + z). This population has a number density n 10 -3 Mpc -3 h 3 galaxies within the 9 Gpc3 h -3 volume to be sampled by our survey, ensuring that the error in the determination of the BAO scale is not limited by shot noise. By itself, such a survey will deliver precisions of order 5% in the dark-energy equation of state parameter w, if assumed constant, and can determine its time derivative when combined with future cosmic microwave background measurements. In addition, PAU will yield high-quality redshift and low-resolution spectroscopy for hundreds of millions of other galaxies, including a very significant high-redshift population. The data set produced by this survey will have a unique legacy value, allowing a wide range of astrophysical studies.
The polarized gamma-ray burst GRB 061122 Götz, D; Covino, S; Fernández-Soto, A ...
Monthly notices of the Royal Astronomical Society,
06/2013, Volume:
431, Issue:
4
Journal Article
Peer reviewed
Open access
We report on the polarization measure, obtained with IBIS on board INTEGRAL, of the prompt emission of GRB 061122. Over an 8 s interval containing the brightest part of the gamma-ray burst (GRB) we ...put a lower limit on its polarization fraction of 60 per cent at 68 per cent confidence level (c.l.) and of 33 per cent at 90 per cent c.l. on the 250-800 keV energy range.
We performed late time optical and near-infrared imaging observations of the GRB field using the Telescopio Nazionale Galileo and the Canada-France-Hawaii Telescope. Our multiband (ugrizYJHK) photometry allowed us to identify the host galaxy of GRB 061122 and to build its spectral energy distribution. Using a photometric redshift code we fitted these data, and derived the basic properties of the galaxy, including its type and redshift, that we could constrain to the interval 0.57, 2.10 at a 90 per cent c.l., with a best-fitting value of z = 1.33.
The polarization measurement in different energy bands, together with the distance determination, allowed us to put the most stringent limit (ξ 3.4 × 10−16) to date to a possible Lorentz invariance violation based on the vacuum birefringence effect, predicted by some quantum-gravity theories.
To assess inappropriate prescribing in older people with diabetes mellitus during the month prior to a hospitalization, using tools on potentially inappropriate medicines (PIMs) and potential ...prescribing omissions (PPOs) and comparing inappropriate prescribing in patients with without diabetes.
In an observational, prospective multicentric study, we assessed inappropriate prescribing in 672 patients aged 75 years and older during hospital admission. The Beers, Screening Tool of Older Person's Prescriptions (STOPP) and Screening Tool to Alert Doctors to Right Treatment (START) criteria and Assessing Care of Vulnerable Elders (ACOVE-3) medicine quality indicators were used. We analysed demographic and clinical factors associated with inappropriate prescribing.
Of 672 patients, 249 (mean age 82.4 years, 62.9% female) had a diagnosis of diabetes mellitus. The mean number of prescribing drugs per patient with diabetes was 12.6 (4.5) vs. 9.4 (4.3) in patients without diabetes (P < 0.001). Of those patients with diabetes, 74.2% used 10 or more medications; 54.5% of patients with diabetes had at least one Beers-listed PIM, 68.1% had at least one STOPP-listed PIM, 64.6% had at least one START-listed PPO and 62.8% had at least one ACOVE-3-listed PPO. Except for the Beers criteria, these prevalences were significantly higher in patients with diabetes than in those without. After excluding diabetes-related items from these tools, only STOPP-listed PIMs remained significantly higher among patients with diabetes (P = 0.04).
Polypharmacy is common among older patients with diabetes mellitus. Inappropriate prescribing is higher in older patients with diabetes, even when diabetes-related treatment is excluded from the inappropriate prescribing evaluation.
The aims of this study were to estimate the prevalence of familial cases in patients with Meniere's disease (MD) and to identify clinical differences between sporadic and familial MD. We recruited ...1375 patients with definite MD according to the American Academy of Otolaryngology‐Head and Neck Surgery criteria, obtaining the familial history of hearing loss or episodic vertigo by direct interview or a postal survey in 1245 cases in a multicenter study. Familial clustering was estimated by the recurrence risk ratio in siblings (λs) and offspring (λo) using intermediate and high prevalence values for MD in European population. A total of 431 patients (34%) reported a familial history of hearing loss or recurrent vertigo and 133 patients had a relative with possible MD. After clinical reevaluation, 93 relatives in 76 families were diagnosed of definite MD (8.4%), including three pairs of monozygotic twins. λs and λo were 16–48 and 4–12, respectively. We observed genetic heterogeneity, but most families had an autosomal dominant inheritance with anticipation. No clinical differences were found between sporadic and familial MD, except for an early onset in familial cases. We may conclude that MD has a strong familial aggregation and that sporadic and familial MDs are clinically identical.
PM01183 is a new compound that blocks active transcription, produces DNA breaks and apoptosis, and affects the inflammatory microenvironment. PM01183 showed strong antitumor activity in preclinical ...models of cisplatin-resistant epithelial ovarian cancer.
Patients with platinum-resistant/refractory ovarian cancer were included in a two-stage, controlled, randomized (in a second stage), multicenter, phase II study. Primary endpoint was overall response rate (ORR) by RECIST and/or GCIG criteria. The exploratory first stage (n = 22) confirmed the activity of PM01183 as a single agent at 7.0 mg flat dose every 3 weeks (q3wk). The second stage (n = 59) was randomized and controlled with topotecan on days 1–5 q3wk or weekly (every 4 weeks, q4wk).
ORR was 23% (95% CI, 13%–37%) for 52 PM01183-treated patients. Median duration of response was 4.6 months (95% CI, 2.5–6.9 months), and 23% (95% CI, 0%–51%) of responses lasted 6 months or more. Ten of the 12 confirmed responses were reported for 33 patients with platinum-resistant disease ORR = 30% (95% CI, 16%–49%); for the 29 patients treated with topotecan in the second stage, no responses were found. Median PFS for all PM01183-treated patients was 4.0 months (95% CI, 2.7–5.6 months), and 5.0 months (95% CI, 2.7–6.9 months) for patients with platinum-resistant disease.
Grade 3/4 neutropenia in 85% of patients; febrile neutropenia in 21% and fatigue (grade 3 in 35%) were the principal safety findings for PM01183.
PM01183 is an active drug in platinum-resistant/refractory ovarian cancer and warrants further development. The highest activity was observed in platinum-resistant disease. Its safety profile indicates the dose should be adjusted to body surface area (mg/m2).
EudraCT 2011-002172-16.
Long gamma-ray bursts (LGRBs) are associated with massive stars and are therefore linked to star formation. To reach our goal we use the Swift/BAT6 complete sample of LGRBs. In this first paper, we ...build the spectral energy distribution (SED) of the 14 z < 1 host galaxies of the BAT6 LGRB sample and determine their stellar masses (M) from SED fitting. To investigate the presence of a bias in the LGRB-star formation relation we compare the stellar mass distribution of the LGRB host galaxies (i) with star-forming galaxies observed in deep surveys (U1traVISTA) within the same redshift limit; (ii) with semi-analytical models of the z < 1 star-forming galaxy population; and (iii) with dedicated numerical simulations of LGRB hosts having different metallicity thresholds for the progenitor star environment. We find that at z < 1, LGRBs tend to avoid massive galaxies and are very powerful for selecting a population of faint low-mass star-forming galaxies, partly below the completeness limits of galaxy surveys.
GRB 090423 at a redshift of z 8.1 Racusin, J. L; Amati, L; Guidorzi, C ...
Nature (London),
10/2009, Volume:
461, Issue:
7268
Journal Article
Peer reviewed
Open access
Gamma-ray bursts (GRBs) are produced by rare types of massive stellar explosion. Their rapidly fading afterglows are often bright enough at optical wavelengths that they are detectable at ...cosmological distances. Hitherto, the highest known redshift for a GRB was z = 6.7 (ref. 1), for GRB 080913, and for a galaxy was z = 6.96 (ref. 2). Here we report observations of GRB 090423 and the near-infrared spectroscopic measurement of its redshift, z = . This burst happened when the Universe was only about 4 per cent of its current age. Its properties are similar to those of GRBs observed at low/intermediate redshifts, suggesting that the mechanisms and progenitors that gave rise to this burst about 600,000,000 years after the Big Bang are not markedly different from those producing GRBs about 10,000,000,000 years later.
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