1,236 research outputs found
Remittances and their Effect on Emigration Intentions in Egypt, Morocco and Turkey
What determines remittances – altruism or enlightened self-interest - and do remittances trigger additional migration? These two questions are examined empirically in Egypt, Turkey and Morocco for households with family members living abroad. Results show, first, that one cannot clearly pinpoint altruistic or motives of self-interest since each country tells a different story and within a country both motives can be defended as driving forces behind remittance behaviour. A general conclusion based on a multi-country study is that the family ties and the net earnin
Modern compact star observations and the quark matter EoS
A hybrid equation of state for dense matter is presented that satisfies
phenomenological constraints from modern compact star observations which
indicate high maximum masses of about 2 M_sun and large radii of R> 12 km. The
corresponding isospin symmetric equation of state is consistent with flow data
analyses of heavy-ion collisions. The transition from nuclear to two-flavor
color superconducting quark matter at n approximately 0.55 fm^{-3} is almost a
crossover.Comment: 2 pages, 2 figures; Proceedings of the Erice School on 'Radioactive
Beams, Nuclear Dynamics and Astrophysics' to be published in 'Prog. Part.
Nucl. Phys.
Constraints on the high-density nuclear equation of state from the phenomenology of compact stars and heavy-ion collisions
A new scheme for testing nuclear matter equations of state (EsoS) at high
densities using constraints from neutron star phenomenology and a flow data
analysis of heavy-ion collisions is suggested. An acceptable EoS shall not
allow the direct Urca process to occur in neutron stars with masses below
, and also shall not contradict flow and kaon production data of
heavy-ion collisions. Compact star constraints include the mass measurements of
2.1 +/- 0.2 M_sun (1 sigma level) for PSR J0751+1807, of 2.0 +/- 0.1 M_sun from
the innermost stable circular orbit for 4U 1636-536, the baryon mass -
gravitational mass relationships from Pulsar B in J0737-3039 and the
mass-radius relationships from quasiperiodic brightness oscillations in 4U
0614+09 and from the thermal emission of RX J1856-3754. This scheme is applied
to a set of relativistic EsoS constrained otherwise from nuclear matter
saturation properties with the result that no EoS can satisfy all constraints
simultaneously, but those with density-dependent masses and coupling constants
appear most promising.Comment: 15 pages, 8 figures, 5 table
Time Trends in the Incidence and Treatment of Extra-Abdominal and Abdominal Aggressive Fibromatosis: A Population-Based Study
Background: Aggressive fibromatosis (AF) is a locally infiltrating soft-tissue tumor. In a population-based study in the Netherlands, we evaluated time trends for the incidence and treatment of AF. Methods: In PALGA: Dutch Pathology Registry, all patients diagnosed between 1993 and 2013 as having extra-abdominal or abdominal wall aggressive fibromatosis were identified and available pathology data of the patients were evaluated. Epidemiological and treatment-related factors were analyzed with χ2and regression analysis. Results: During the study period, 1134 patients were identified. The incidence increased from 2.10 to 5.36 per million people per year. Median age at the time of diagnosis increased annually by B 0.285 (P = 0.001). Female gender prevailed and increased over time [annual odds ratio (OR) 1.022; P = 0.058]. All anatomic localizations, but in particular truncal tumors, became more frequent. During the study period diagnostic histological biopsies were performed more often (annual OR 1.096; P < 0.001). The proportion of patients who underwent surgical treatment decreased (annual OR 0.928; P < 0.001). When resection was preceded by biopsy, 49.8 % of the patients had R0-resection versus 30.7 % in patients without biopsy (P < 0.001). Conclusions: In this population-based study, an increasing incidence of extra-abdominal and abdominal-wall aggressive fibromatosis was observed. The workup of patients improved and a trend towards a nonsurgical treatment policy was observed
Long-Term Outcome of Sustained Endocrine Monotherapy for Elderly Breast Cancer Patients
Background: Among elderly breast cancer patients, endocrine therapy may be chosen as definitive treatment by patients or physicians. This study investigated the efficacy of endocrine monotherapy (ET) in terms of avoidance of invasive local treatment. Methods: Elderly patients (≥70 years) with a diagnosis of estrogen receptor-positive breast cancer who underwent ET between 2008 and 2015 were identified through the Netherlands Cancer Registry. The primary outcome was the cumulative risk of undergoing invasive local treatment (radiotherapy or surgery) for the primary tumor. The secondary outcomes were development of uncontrolled local disease and overall survival (OS). Results: Of the 105 patients (median age, 86 years) enrolled in this study, 91 (78 %) received ET as definitive treatment, whereas 14 received ET as a “bridge to surgery.” For the 91 patients who used ET as intended definitive treatment, the 5-year cumulative risk of undergoing invasive local treatment and experiencing uncontrolled disease were respectively 28 % and 16 %. The 5-year cumulative OS was 42 %. Whereas 11 patients had metastatic or locally progressive breast cancer at the time of death, cardiovascular disease, infectious diseases, and old age or dementia were reported as contributing to the death of 39 patients. Conclusions: For a select group of elderly breast cancer patients who received sustained ET, the risk of undergoing invasive local treatment was surpassed by a twofold higher risk of dying. As an alternative to invasive local treatment, ET can be discussed as a safe and effective option for patients unwilling or unfit to undergo surgery.</p
Aspects of particle production in isospin asymmetric matter
The production/absorption rate of particles in compressed and heated
asymmetric matter is studied using a Relativistic Mean Field (RMF) transport
model with an isospin dependent collision term. Just from energy conservation
in the elementary production/absorption processes we expect to see a strong
dependence of the yields on the basic Lorentz structure of the isovector
effective interaction, due to isospin effects on the scalar and vector
self-energies of the hadrons. This will be particularly evident for the ratio
of the rates of particles produced with different charges: results are shown
for \pi(+)/\pi(-), K(+)/K(0) yields. In order to simplify the analysis we
perform RMF cascade simulations in a box with periodic boundary conditions. In
this way we can better pin down all such fine relativistic effects in particle
production, that could likely show up even in realistic heavy ion collisions.
In particular, K(+,0) production is expected to be directly related to the high
density behaviour of the symmetry energy, since kaons are produced very early
during the high density stage of the collision and their mean free path is
rather large. We show that the K(+)/K(0) ratio reflects important isospin
contributions on the production rates just because of the large sensitivity
around the threshold. The results are very promising for the possibility of a
direct link between particle production data in exotic Heavy Ion Collisions and
the isospin dependent part of the Equation of State at high baryon densities.Comment: 26 pages, 8 figures; Nucl.Phys. A, accepte
Modern compact star observations and the quark matter equation of state
We present a hybrid equation of state (EoS) for dense matter that satisfies
phenomenological constraints from modern compact star (CS) observations which
indicate high maximum masses (M = 2 M_sun) and large radii (R> 12 km). The
corresponding isospin symmetric EoS is consistent with flow data analyses of
heavy-ion collisions and a deconfinement transition at approx. 0.55 fm^{-3}.
The quark matter phase is described by a 3-flavor Nambu--Jona-Lasinio model
that accounts for scalar diquark condensation and vector meson interactions
while the nuclear matter phase is obtained within the
Dirac-Brueckner-Hartree-Fock (DBHF) approach using the Bonn-A potential. We
demonstrate that both pure neutron stars and neutron stars with quark matter
cores (QCSs) are consistent with modern CS observations. Hybrid star
configurations with a CFL quark core are unstable.Comment: 16 pages, 4 figures; published version, important note added in proo
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