9 research outputs found
The quest for companions to post-common envelope binaries. II. NSVS14256825 and HS0705+6700
We report new mid-eclipse times of the two close binaries NSVS14256825 and
HS0705+6700, harboring an sdB primary and a low-mass main-sequence secondary.
Both objects display clear variations in the measured orbital period, which can
be explained by the action of a third object orbiting the binary. If this
interpretation is correct, the third object in NSVS14256825 is a giant planet
with a mass of roughly 12 M_Jup. For HS0705+6700, we provide evidence that
strengthens the case for the suggested periodic nature of the eclipse time
variation and reduces the uncertainties in the parameters of the brown dwarf
implied by that model. The derived period is 8.4 yr and the mass is 31 M_Jup,
if the orbit is coplanar with the binary. This research is part of the
PlanetFinders project, an ongoing collaboration between professional
astronomers and student groups at high schools.Comment: Accepted by Astron. and Astrophy
EC 10246-2707: a new eclipsing sdB + M dwarf binary⋆
We announce the discovery of a new eclipsing hot subdwarf B + M dwarf binary,
EC 10246-2707, and present multi-colour photometric and spectroscopic observations
of this system. Similar to other HW Vir-type binaries, the light curve shows both
primary and secondary eclipses, along with a strong reflection effect from the M dwarf;
no intrinsic light contribution is detected from the cool companion. The orbital period
is 0.118 507 993 6 ± 0.000 000 000 9 days, or about three hours. Analysis of our time-
series spectroscopy reveals a velocity semi-amplitude of K1 = 71.6 ± 1.7 km s−1 for
the sdB and best-fitting atmospheric parameters of Teff = 28900 ± 500 K, log g =
5.64 ± 0.06, and log N(He)/N(H) = -2.5 ± 0.2. Although we cannot claim a unique
solution from modeling the light curve, the best–fitting model has an sdB mass of 0.45
M⊙ and a cool companion mass of 0.12 M⊙. These results are roughly consistent with
a canonical–mass sdB and M dwarf separated by a ∼ 0.84 R⊙. We find no evidence of
pulsations in the light curve and limit the amplitude of rapid photometric oscillations
to < 0.08%. Using 15 years of eclipse timings, we construct an O-C diagram but find
no statistically significant period changes; we rule out | ˙P | > 7.2×10−12. If EC 10246-
2707 evolves into a cataclysmic variable, its period should fall below the famous CV
period gap.Web of Scienc
The economic determinants of foreign direct investment in developing countries and transition economies
The economic growth rates have dramatically increased in developing economies, such as in Latin American, Asian, and Eastern European countries, following the financial liberalisation attempt, especially during the 1990s. Foreign direct investment (FDI) has become an increasingly important element for economic development and integration of developing countries and transition economies in this period with the world economy. The main purpose of this study is to develop an empirical framework to estimate the economic determinants of FDI inflows by employing a panel data set of 17 developing countries and transition economies for the period of 1989:01-2006:04. In our model there are seven explanatory economic variables. They are, respectively, the previous period FDI (the pull factor for new FDI), GDP growth (measures market size), Wage (unit labour costs), Trade Rate (measures the openness of countries), the real interest rates (measures macroeconomic policy), inflation rate (as country risk and macroeconomic policy), and domestic investment (Business Climate). Hence, throughout the paper, only the economic determinants (being separated and apart from the other studies in the literature) of FDI inflows to developing countries and transition economies are studied. It is found out that the previous period FDI which is directly related to the host countries' economic resources is important as an economic determinant. Besides, it is also understood that the main determinants of FDI inflows are the inflation rate, the interest rate, the growth rate, and the trade (openness) rate and FDI inflows give power to the economies of host countries
Anxiety and depression states of adolescents with polycystic ovary syndrome
Background/aim: Various studies have shown that adult patients with polycystic ovary syndrome (PCOS) have higher levels of anxiety and depression compared to their normal counterparts. However, it is still unclear whether these mood disorders already exist in adolescents affected by PCOS. The aim of the present study is to assess differences in anxiety and depression levels between adolescents with PCOS and age-and body mass index (BMI)-matched controls and to determine the possible factor(s) impacting these psychological parameters in adolescents with PCOS. Materials and methods: The study included 80 adolescents with PCOS and 50 age-and BMI-matched controls. All participants completed standardized questionnaires assessing anxiety and depression. A multiple linear regression model was used to analyze the impact of potential variables on anxiety and depression scores of the adolescents with PCOS. Results: Significantly higher levels of anxiety, specifically generalized and social anxieties, as well as depression were found in adolescents with PCOS compared to controls. Higher BMI was found to be associated with higher levels of depression and generalized anxiety, and higher modified Ferriman-Gallwey score with higher level of panic disorder in adolescents affected by PCOS. Conclusion: Adolescents with PCOS experience significantly more emotional distress compared to adolescents without PCOS. This emotional distress may be related, at least in part, to certain clinical features of PCOS including obesity and hirsutism. PCOS in adolescents should be assessed not only for the gynecological and metabolic aspects but also for the emotional aspects of the disease
Quality-of-life evaluation of healthy siblings of children with chronic Illness
Background: Chronic disease of children can cause changes in the
health-related quality of life (HrQoL) of the family members.
Aims: To evaluate the HrQoL of healthy siblings of children with chronic
disease.
Study Design: Cross-sectional study.
Methods: The study included healthy sibling of children with chronic
disease (cerebral palsy, epilepsy; diabetes, celiac disease,
hematologic/ oncologic disease, or asthma) and healthy sibling of
healthy children to evaluate the quality of life. We used the Pediatric
Quality of Life Inventory questionnaire; the physical health and
psychosocial health scores were calculated using the responses of the
sibling and parent. The primary endpoint was the comparison of HrQoL
scores of healthy siblings of children with chronic disease and that of
healthy siblings of healthy children.
Results: This study included a respective healthy sibling of 191
children with chronic disease and healthy sibling of 100 healthy
children. The physical health, psychosocial health, and total health
scores of healthy siblings of children with chronic disease were
significantly lower than that of healthy siblings of healthy children
(p<0.001). Among the healthy siblings of children with chronic disease,
the lowest psychosocial health score was found in the siblings of
children with cerebral palsy, hematologic/oncologic disease. and asthma
(p<0.001). The global impact on the quality of life for healthy siblings
of children with chronic disease was significantly higher in the
self-report of the children than that of the parents (30.4\% versus
15.1\%, p<0.05).
Conclusion: Most healthy siblings of children with chronic disease are
physically and psychosocially affected and there is low parental
awareness of this condition. This can increase the risk of emotional
neglect and abuse of these children. Therefore. special support programs
are needed for the families of children with chronic diseases