110 research outputs found
Rotating neutron stars: an invariant comparison of approximate and numerical spacetime models
We compare three different models of rotating neutron star spacetimes: the
Hartle-Thorne (HT) slow-rotation approximation at second order in rotation, the
exact analytic vacuum solution of Manko et al. and a numerical solution of the
full Einstein equations. We integrate the HT structure equations for five
representative equations of state. Then we match the HT models to numerical
solutions of the Einstein equations, imposing that the mass and angular
momentum of the models be the same. We estimate the limits of validity of the
HT expansion computing relative errors in the spacetime's quadrupole moment Q
and in the ISCO radii. We find that ISCO radii computed in the HT approximation
are accurate to better than 1%, even for the fastest observed ms pulsar. At the
same rotational rates the accuracy on Q is of order 20%. In the second part of
the paper we focus on the exterior vacuum spacetimes. We introduce a physically
motivated `quasi-Kinnersley' Newman-Penrose frame. In this frame we evaluate
the speciality index S, a coordinate-independent quantity measuring the
deviation of each model from Petrov Type D. On the equatorial plane this
deviation is smaller than 5%, even for the fastest rotating models. Our main
conclusion is that the HT approximation is very reliable for most astrophysical
applications.Comment: 19 pages, 9 figures, accepted in MNRAS; improved presentation, some
new analytical results in Section 5.
Um texto Ă© um corpo e, sendo corpo, pulsa uma infinidade de outros
Um texto Ă© um corpo e, sendo corpo, pulsa uma infinidade de outros por Bruni Emanuel
Quantum sensors for dynamical tracking of chemical processes
Quantum photonics has demonstrated its potential for enhanced sensing.
Current sources of quantum light states tailored to measuring, allow to monitor
phenomena evolving on time scales of the order of the second. These are
characteristic of product accumulation in chemical reactions of technologically
interest, in particular those involving chiral compounds. Here we adopt a
quantum multiparameter approach to investigate the dynamic process of sucrose
acid hydrolysis as a test bed for such applications. The estimation is made
robust by monitoring different parameters at once
PHYSICAL ACTIVITY AND EARLY CHILDHOOD EDUCATION: TOWARDS A CRITICAL SPORTS PEDAGOGY
So-called “Bolonia Process” has reformed national education systems in Europe and introduced the figure of a general teacher in primary schools and kindergartens. This has also happened in Italy, where early childhood educators and primary teachers are trained in University departments of Educational Sciences to become general educators and teachers in both Kindergartens and primary schools without any specific training, for example, in physical/ sports education. This lack in the preparation of kindergarten educators and primary school teachers is causing a decrease of interest for the teaching of physical activity and sports education by kindergartens educators. Usually, an educator who has scarce or not-enough developed competencies in a specific subject matter of the curriculum does not like to be involved in such a kind of activities. The consequences of this can be seen in the reduction of the level of physical and motor competencies and skills in the children attending kindergartens. Starting from this genesis, the primary aim of this paper is to reflect upon the consequences of the new reform of European educational systems on the teaching of physical activity in the kindergarten and early childhood, and upon the educational challenges they imply for teachers. In conclusion, will show the key role that the general teacher with specific competencies and skills in physical and sports education can play, along with family, to foster physical and sports education in early childhood and sketch a possible model for teaching it
Sleep habits and pattern in 1-14 years old children and relationship with video devices use and evening and night child activities
Background: Sleep in childhood and adolescence is crucial for mental and physical health; however several researches reported an increasing trend towards a sleep deprivation in this age. Due to the lack of recent epidemiological studies in Italy, the aim of our study was to depict sleep habits and patterns in Italian children aged 1-14 years and to evaluate their relationships with video devices use (TV, tablet, smartphone, PC) and evening/night child activities. Methods: A structured interview was conducted during 2015 by 72 Family Pediatricians in 2030 healthy children aged 1-14 years by a cross-sectional survey named "Ci piace sognare". Total sleep duration was calculated, 2015 National Sleep Foundation Recommendations were used as reference. Optimal sleepers were defined children sleeping in own bed all night without awakenings. Multivariable median regression was performed to identify predictors of sleep duration and multivariable logistic regression for predictors of optimal sleep. Results: Total sleep duration and numbers of awakenings decreased with age. Only 66.9% of children had sleep duration in agreement with Recommendations (50% in 10-14 years group). Before sleeping 63.5% of children used video devices (39.6% at 1-3 years), 39.1% read, 27.5% drank and 19.5% ate. Bottle users at bedtime were 30.8% at 1-3 years, 16.6% at 3-5 years and 4.9% at 5-7 years. Overall, 23.4% of children changed sleeping place during the night, 22.4% referred sleeping problems in the first year of life. Video devices use was negative predictor of sleep duration (-0.25 h [95% CI:-0.35,-0.14], p < 0.001). Optimal sleep was inversely related with bedroom TV (OR 0.63 [0.50,0.79], p < 0.001), with sleeping disorders in the first year (OR 0.62 [0.48,0.80], p < 0.001)), with bottle use (OR 0.64 [0.44,0.94], p < 0.05) and posivively related with high mother's education level (OR 1.44 [1.11,1.88], p < 0.01). Conclusions: About one third of 1 to 14 year Italian children sleep less than recommended, one half in teenage. Modifiable risk factors for sleep abnormalities such as video devices use, bedroom TV and bottle use should be target of preventive strategies for a correct sleep. Pediatricians should give priority to the identification of sleep disorders early in life
Early results of PRO-EPI: PROspective multicenter observational study on elective pelvic nodes irradiation in patients with intermediate/high/very high-risk non-metastatic prostate cancer submitted to radical, adjuvant, or salvage radiotherapy with or without concomitant androgen deprivation therapy
Simple Summary: Although radiotherapy plays a fundamental role in the management of intermediate/high/very high-risk non-metastatic prostatic cancer (IHR-nmPca), there is still no consensus on the optimal treatment strategy in this setting. Remarkably, the role of elective nodal irradiation (ENI) is still highly controversial. The PROspective multicenter observational study on Elective Pelvic nodes Irradiation (PRO-EPI) was designed to provide "real life" data regarding the patterns of care for IHR-nmPca.Forty-three Italian Radiation Oncology centers participated in the PROspective multicenter observational study on Elective Pelvic nodes Irradiation (PRO-EPI) project, with 1029 patients enrolled. In this preliminary analysis, we longitudinally evaluated the impact of Elective Nodal Irradiation (ENI) and radiotherapy features on toxicity and quality of life (QoL). Six months follow-up data were available for 913 patients and 12 months data for 762 patients. Elective Nodal Irradiation was given to 506 patients (48.9%). Volumetric Intensity-Modulated Radiation Therapy (IMRT) was adopted in more than 77% of patients and Image-Guided Radiation Therapy (IGRT) in 84.4%. Androgen deprivation therapy (ADT) was administered to the majority of patients (68.3%), and it was associated to ENI in 408 cases (81.1%). Toxicity was mostly mild and reversible and IGRT resulted in a significant reduction of rectal toxicity, although a non-significant trend toward increased urinary toxicity was observed. No statistically significant differences in QoL and toxicity were seen in patients treated with or without ENI. The adoption of IGRT is widespread and increasing and could reduce treatment toxicity. ENI is not yet the standard treatment, but it is performed in a growing fraction of cases and not resulting into an increase in toxicity or in a deterioration of QoL. Further analyses are needed to clarify the long-term toxicity profile and the impact of ENI on survival
Sleep habits and pattern in 1-14 years old children and relationship with video devices use and evening and night child activities
Background: Sleep in childhood and adolescence is crucial for mental and physical health; however several researches reported an increasing trend towards a sleep deprivation in this age. Due to the lack of recent epidemiological studies in Italy, the aim of our study was to depict sleep habits and patterns in Italian children aged 1-14 years and to evaluate their relationships with video devices use (TV, tablet, smartphone, PC) and evening/night child activities. Methods: A structured interview was conducted during 2015 by 72 Family Pediatricians in 2030 healthy children aged 1-14 years by a cross-sectional survey named "Ci piace sognare". Total sleep duration was calculated, 2015 National Sleep Foundation Recommendations were used as reference. Optimal sleepers were defined children sleeping in own bed all night without awakenings. Multivariable median regression was performed to identify predictors of sleep duration and multivariable logistic regression for predictors of optimal sleep. Results: Total sleep duration and numbers of awakenings decreased with age. Only 66.9% of children had sleep duration in agreement with Recommendations (50% in 10-14 years group). Before sleeping 63.5% of children used video devices (39.6% at 1-3 years), 39.1% read, 27.5% drank and 19.5% ate. Bottle users at bedtime were 30.8% at 1-3 years, 16.6% at 3-5 years and 4.9% at 5-7 years. Overall, 23.4% of children changed sleeping place during the night, 22.4% referred sleeping problems in the first year of life. Video devices use was negative predictor of sleep duration (-0.25 h [95%CI:-0.35,-0.14], p < 0.001). Optimal sleep was inversely related with bedroom TV (OR 0.63 [0.50,0.79], p < 0.001), with sleeping disorders in the first year (OR 0.62 [0.48,0.80], p < 0.001)), with bottle use (OR 0.64 [0.44,0.94], p < 0.05) and posivively related with high mother's education level (OR 1.44 [1.11,1.88], p < 0.01). Conclusions: About one third of 1 to 14 year Italian children sleep less than recommended, one half in teenage. Modifiable risk factors for sleep abnormalities such as video devices use, bedroom TV and bottle use should be target of preventive strategies for a correct sleep. Pediatricians should give priority to the identification of sleep disorders early in life
Biomodulatory Treatment With Azacitidine, All-trans Retinoic Acid and Pioglitazone Induces Differentiation of Primary AML Blasts Into Neutrophil Like Cells Capable of ROS Production and Phagocytosis
Effective and tolerable salvage therapies for elderly patients with chemorefractory acute myeloid leukemia (AML) are limited and usually do not change the poor clinical outcome. We recently described in several chemorefractory elderly AML patients that a novel biomodulatory treatment regimen consisting of low-dose azacitidine (AZA) in combination with PPAR gamma agonist pioglitazone (PGZ) and all-trans retinoic acid (ATRA) induced complete remission of leukemia and also triggered myeloid differentiation with rapid increase of peripheral blood neutrophils. Herein, we further investigated our observations and comprehensively analyzed cell differentiation in primary AML blasts after treatment with ATRA, AZA, and PGZ ex vivo. The drug combination was found to significantly inhibit cell growth as well as to induce cell differentiation in about half of primary AML blasts samples independent of leukemia subtype. Notably and in comparison to ATRA/AZA/PGZ triple-treatment, effects on cell growth and myeloid differentiation with ATRA monotherapy was much less efficient. Morphological signs of myeloid cell differentiation were further confirmed on a functional basis by demonstrating increased production of reactive oxygen species as well as enhanced phagocytic activity in AML blasts treated with ATRA/AZA/PGZ. In conclusion, we show that biomodulatory treatment with ATRA/AZA/PGZ can induce phenotypical and functional differentiation of primary AML blasts into neutrophil like cells, which aside from its antileukemic activity may lower neutropenia associated infection rates in elderly AML patients in vivo. Clinical impact of the ATRA/AZA/PGZ treatment regimen is currently further investigated in a randomized clinical trial in chemorefractory AML patients (NCT02942758)
Dose-escalated pelvic radiotherapy for prostate cancer in definitive or postoperative setting
Purpose Given the absence of standardized planning approach for clinically node-positive (cN1) prostate cancer (PCa), we collected data about the use of prophylactic pelvic irradiation and nodal boost. The aim of the present series is to retrospectively assess clinical outcomes after this approach to compare different multimodal treatment strategies in this scenario. Methods Data from clinical records of patients affected by cN1 PCa and treated in six different Italian institutes with prophylactic pelvic irradiation and boost on pathologic pelvic lymph nodes detected with CT, MRI or choline PET/CT were retrospectively reviewed and collected. Clinical outcomes in terms of overall survival (OS) and biochemical relapse-free survival (b-RFS) were explored. The correlation between outcomes and baseline features (International Society of Urological Pathology-ISUP pattern, total dose to positive pelvic nodes 60 Gy, sequential or simultaneous integrated boost (SIB) administration and definitive vs postoperative treatment) was explored. Results ISUP pattern < 2 was a significant predictor of improved b-RFS (HR = 0.3, 95% CI 0.1220-0.7647, P = 0.0113), while total dose < 60 Gy to positive pelvic nodes was associated with worse b-RFS (HR = 3.59, 95% CI 1.3245-9.741, P = 0.01). Conversely, treatment setting (postoperative vs definitive) and treatment delivery technique (SIB vs sequential boost) were not associated with significant differences in terms of b-RFS (HR = 0.85, 95% CI 0.338-2.169, P = 0.743, and HR = 2.39, 95% CI 0.93-6.111, P = 0.067, respectively). Conclusion Results from the current analysis are in keeping with data from literature showing that pelvic irradiation and boost on positive nodes are effective approaches. Upfront surgical approach was not associated with better clinical outcomes
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