2,439 research outputs found
Chemical evolution of the bulge of M31: predictions about abundance ratios
We aim at reproducing the chemical evolution of the bulge of M31 by means of
a detailed chemical evolution model, including radial gas flows coming from the
disk. We study the impact of the initial mass function, the star formation rate
and the time scale for bulge formation on the metallicity distribution function
of stars. We compute several models of chemical evolution using the metallicity
distribution of dwarf stars as an observational constraint for the bulge of
M31. Then, by means of the model which best reproduces the metallicity
distribution function, we predict the [X/Fe] vs. [Fe/H] relations for several
chemical elements (O, Mg, Si, Ca, C, N). Our best model for the bulge of M31 is
obtained by means of a robust statistical method and assumes a Salpeter initial
mass function, a Schmidt-Kennicutt law for star formation with an exponent
k=1.5, an efficiency of star formation of , and an
infall timescale of Gyr. Our results suggest that the bulge
of M31 formed very quickly by means of an intense star formation rate and an
initial mass function flatter than in the solar vicinity but similar to that
inferred for the Milky Way bulge. The [/Fe] ratios in the stars of the
bulge of M31 should be high for most of the [Fe/H] range, as is observed in the
Milky Way bulge. These predictions await future data to be proven.Comment: Accepted for publication by MNRA
Gate stability of GaN-Based HEMTs with P-Type Gate
status: publishe
Usability improvements of the Thermipig model for precision pig farming
Pig livestock farming systems encounter several economic and environmental
challenges, connected with meat price decrease, sanitary norms, emissions etc. To deal with these
issues, methods and models to assess the performance of a pig production system have been
developed. For instance, Thermipig model represents the pig fattening room and simulates
performances of pigs at the batch level, taking into account interactions between the individual
variability of pigs, farmer's practices, room characteristics and outdoor climate conditions. The
model requires some static basic inputs fulfilled in several spreadsheets (such as rooms, pigs, and
dietary characteristics) but also data files for voluminous variable inputs (such as outdoor
temperature or climate control box parameters) for further modelling and outcome producing.
This leads to challenges in data providing by the farmers and have to be improved. This paper
deals with the implementation of the separate modules of the developed data warehouse system
for usability improvements of the Thermipig model. The idea is to substitute input from the data
files with online data input and automated variable processing by the model using the python
script for connection to the remote data warehouse. The data warehouse system is extended with
‘Property Sets’ section dealing with all the operations that can be performed to a set of input
variables. This approach demonstrates the ability of the data warehouse to act as data supplier for
the remote model. As well the outcome of the model is also transferable back to the data
warehouse for evaluation. This work is done within the Era-Net SuSan PigSys project - Improving
pig system performance through a whole system approach
A bright impulsive solar burst detected at 30 THz
Ground- and space-based observations of solar flares from radio wavelengths
to gamma-rays have produced considerable insights but raised several unsolved
controversies. The last unexplored wavelength frontier for solar flares is in
the range of submillimeter and infrared wavelengths. Here we report the
detection of an intense impulsive burst at 30 THz using a new imaging system.
The 30 THz emission exhibited remarkable time coincidence with peaks observed
at microwave, mm/submm, visible, EUV and hard X-ray wavelengths. The emission
location coincides with a very weak white-light feature, and is consistent with
heating below the temperature minimum in the atmosphere. However, there are
problems in attributing the heating to accelerated electrons. The peak 30 THz
flux is several times larger than the usual microwave peak near 9 GHz,
attributed to non-thermal electrons in the corona. The 30 THz emission could be
consistent with an optically thick spectrum increasing from low to high
frequencies. It might be part of the same spectral component found at sub-THz
frequencies whose nature remains mysterious. Further observations at these
wavelengths will provide a new window for flare studies.Comment: 9 pages, 11 figures, accepted by Astrophysical Journal, March 23,
201
Experts’ consensus on the definition and management of high risk multiple myeloma
High risk multiple myeloma (HRMM) at diagnosis is currently recognized according to the Revised International Staging System (R-ISS) which was set up in 2015. Since then, new clinical and biological prognostic factors have been developed, which could implement the definition of High Risk (HR) category. We conducted a survey in order to identify which additional parameters, both clinical and biological, are considered more useful for the clinical practice and to evaluate if the management of Multiple Myeloma (MM) should change on the basis of the risk category. A questionnaire, consisting of 8 statements, was submitted to 6 Italian experts, from the European Myeloma Network (EMN) Research Italy, using the Delphi method. The colleagues were asked to answer each question using a scale between 0 and 100. If a statement did not reach at least 75 out of 100 points from all the participants, it was rephrased on the basis of the proposal of the experts and resubmitted in a second or further round, until a consensus was reached among all. From the first round of the survey a strong consensus was reached regarding the opportunity to revise the R-ISS including chromosome 1 abnormality, TP53 mutation or deletion, circulating plasma cells by next generation flow and extramedullary plasmacytomas. No consensus was reached for the definition of “double hit” MM and for the application in clinical practice of treatment strategies based on the risk category. In the second round of the Delphi questionnaire, “double-hit” MM was recognized by the association of at least two high-risk cytogenetic or molecular abnormalities. Moreover, the experts agreed to reserve an intensified treatment only to specific conditions, such as plasma cell leukaemia or patients with multiple extramedullary plasmacytomas, while they admitted that there are not sufficient real word data in order to modify treatment on the basis of MRD assessment in clinical practice. This survey suggests that the definition of HRMM should be implemented by additional clinical and biological risk factors, that will be useful to guide treatment in the future
Peso relativo de órgãos de frangos de corte alimentados com diferentes dietas.
No Brasil, para atender as exigências nutricionais, as dietas para monogástricos são formuladas principalmente a base de milho e farelo de soja, entretanto estas matérias-primas apresentam alto valor no mercado, com isso, tem-se buscado alternativas para substitui-las nas dietas. Por outro lado, alimentos alternativos podem conter fatores antinutricionais, como por exemplo os fitatos que podem formar complexos insolúveis com proteínas e minerais ? reduzindo a disponibilidade destes nutrientes. O uso de enzimas exógenas nas dietas de frangos pode trazer alguns benefícios, tais como: redução na viscosidade da digesta, melhora da digestão e absorção de nutrientes, aumento no consumo alimentar, melhora ganho de peso e na conversão alimentar, diminuição do tamanho do trato gastrointestinal, alteração na população de microrganismos do trato gastrointestinal, redução do consumo de água e do conteúdo de água nas excretas e reduz a excreção de nutrientes (2). Objetivou-se com este trabalho avaliar o efeito das dietas experimentais sobre o peso relativo da moela, fígado e ceco de frangos de corte, quando alimentados com com dietas contendo diferentes matérias primas na presença e ausência de fitase
Retrospective Chart Review of Dabrafenib Plus Trametinib in Patients with Metastatic BRAF V600-Mutant Melanoma Treated in the Individual Patient Program (DESCRIBE Italy)
Background: Real-world data on extended follow-up of patients with BRAF V600-mutant metastatic melanoma are limited. We investigated dabrafenib plus trametinib (dab + tram) outside of a clinical trial setting (Individual Patient Program; DESCRIBE Italy).
Objective: To describe the baseline features, treatment patterns, efficacy, and safety outcomes in patients with BRAF V600-mutant unresectable or metastatic melanoma who had received dab + tram as part of the Managed Access Program (MAP) in Italy.
Patients and methods: An observational, retrospective chart review was conducted in Italian patients with BRAF V600-mutant unresectable stage III/IV melanoma receiving dab + tram as part of the MAP. Baseline features, treatment patterns, efficacy, and safety outcomes were evaluated.
Results: Overall, 499 patients were included in this analysis. BRAF V600E mutation was seen in 81.4% of patients. Overall response rate achieved in 243 of the 390 evaluable patients was 62.3% (95% CI 57.5-67.1). Median progression-free survival (PFS) was 9.3 months (95% CI 8.6-10.6). Subgroup analyses revealed that patients with normal lactate dehydrogenase (LDH) and ≤ three metastatic sites without brain metastases at baseline had better outcomes. With normal LDH at baseline, median PFS for patients with one or two metastatic sites other than cerebral was 18 months. No new safety signals were observed. Treatment was permanently discontinued because of treatment-emergent adverse events (TEAEs) in 9.2% of patients, and pyrexia (27.3%) was the most common TEAE, with a lower incidence than that in the phase 3 studies of dab + tram.
Conclusion: Treatment of BRAF V600E-mutant metastatic melanoma with dab + tram in the real-world setting was effective and safe, including the unselected population with several patients having a high tumor burden - concordant with the results of the pivotal phase 3 studies of dab + tram
Bright 30 THz Impulsive Solar Bursts
Impulsive 30 THz continuum bursts have been recently observed in solar
flares, utilizing small telescopes with a unique and relatively simple optical
setup concept. The most intense burst was observed together with a GOES X2
class event on October 27, 2014, also detected at two sub-THz frequencies,
RHESSI X-rays and SDO/HMI and EUV. It exhibits strikingly good correlation in
time and in space with white light flare emission. It is likely that this
association may prove to be very common. All three 30 THz events recently
observed exhibited intense fluxes in the range of 104 solar flux units,
considerably larger than those measured for the same events at microwave and
sub-mm wavelengths. The 30 THz burst emission might be part of the same
spectral burst component found at sub-THz frequencies. The 30 THz solar bursts
open a promising new window for the study of flares at their originComment: 11 pages, 4 Figures J. Geophys. Res - Space Physics, accepted, May
21, 201
Cross-sectional associations between air pollution and chronic bronchitis: an ESCAPE meta-analysis across five cohorts
BACKGROUND: This study aimed to assess associations of outdoor air pollution on prevalence of chronic bronchitis symptoms in adults in five cohort studies (Asthma-E3N, ECRHS, NSHD, SALIA, SAPALDIA) participating in the European Study of Cohorts for Air Pollution Effects (ESCAPE) project. METHODS: Annual average particulate matter (PM10, PM2.5, PMabsorbance, PMcoarse), NO2, nitrogen oxides (NOx) and road traffic measures modelled from ESCAPE measurement campaigns 2008-2011 were assigned to home address at most recent assessments (1998-2011). Symptoms examined were chronic bronchitis (cough and phlegm for ≥3 months of the year for ≥2 years), chronic cough (with/without phlegm) and chronic phlegm (with/without cough). Cohort-specific cross-sectional multivariable logistic regression analyses were conducted using common confounder sets (age, sex, smoking, interview season, education), followed by meta-analysis. RESULTS: 15 279 and 10 537 participants respectively were included in the main NO2 and PM analyses at assessments in 1998-2011. Overall, there were no statistically significant associations with any air pollutant or traffic exposure. Sensitivity analyses including in asthmatics only, females only or using back-extrapolated NO2 and PM10 for assessments in 1985-2002 (ECRHS, NSHD, SALIA, SAPALDIA) did not alter conclusions. In never-smokers, all associations were positive, but reached statistical significance only for chronic phlegm with PMcoarse OR 1.31 (1.05 to 1.64) per 5 µg/m(3) increase and PM10 with similar effect size. Sensitivity analyses of older cohorts showed increased risk of chronic cough with PM2.5abs (black carbon) exposures. CONCLUSIONS: Results do not show consistent associations between chronic bronchitis symptoms and current traffic-related air pollution in adult European populations
Rheology, clinical efficacy and sensorial of a silicone-based formulation containing pearl extract
In traditional Chinese medicine, pearl extract is believed to nourish skin and prevent the aging process. Thus, the aim of this study was to evaluate rheological characteristics, immediate effects on skin, and sensory properties of a silicone-based cosmetic formulation containing pearl extract. Formulations containing pearl extract or not were submitted to physical stability assays by determinations of its rheological behavior during 28 days storage. Once confirmed the formulation’s stability, they were applied on the volar forearm of 15 healthy female to evaluate skin properties by non-invasive techniques. After a single application, formulations increased the stratum corneum water content. Once applied on the volar forearm for sensory analysis, the volunteer’s majority noted that both formulations improved all the sensory skin attributes, but only the pearl extract formulation has shown the higher scores for all attributes. Results suggested that the silicone-based formulation supplemented with the pearl extract could combine unique sensory properties and effectiveness to better meet consumer’s demand
- …