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Theoretical calculations and some indirect observations show that massive exoplanets on tight orbits must decay due to tidal dissipation within their host stars. This orbital evolution could be observationally accessible through precise transit timing over a course of decades. The rate of planetary in-spiraling may not only help us to understand some aspects of evolution of planetary systems, but also can be used as a probe of the stellar internal structure. In this paper we present results of transit timing campaigns organized for a carefully selected sample of the Northern hemisphere hot Jupiter-like planets which were found to be the best candidates for detecting planet-star tidal interactions. Among them, there is the WASP-12 system which is the best candidate for possessing an in-falling giant exoplanet. Our new observations support the scenario of orbital decay of WASP-12 b and allow us to refine its rate. The derived tidal quality parameter of the host star Q¿ ¿ = (1.82 ± 0.32) × 105 is in agreement with theoretical predictions for subgiant stars. For the remaining systems - HAT-P-23, KELT-1, KELT-16, WASP-33, and WASP-103 - our transit timing data reveal no deviations from the constant-period models, hence constraints on the individual rates of orbital decay were placed. The tidal quality parameters of host stars in at least four systems - HAT-P-23, KELT-1, WASP-33, and WASP-103 - were found to be greater than the value reported for WASP-12. This is in line with the finding that those hosts are main sequence stars, for which efficiency of tidal dissipation is predicted to be relatively weak. © 2018 Copernicus Foundation for Polish Astronomy. All rights reserved.© 2018 Copernicus Foundation for Polish Astronomy. All rights reserved. ; We thank the referee for valuable comments which improved the paper. We also thank Dr. Laetitia Delrez and Dr. Pedro Sada for sharing the WASP-103 and HAT-P-23 light curves with us. GM and MS acknowledge the financial support from the National Science Centre, Poland through grant no. 2016/23/B/ST9/00579. MF acknowledges financial support from grants AYA2014-54348-C3-1-R and AYA2016-79425-C3-3-P of the Spanish Ministry of Economy and Competitiveness (MINECO), co-funded with EU FEDER funds. DD acknowledges the financial support of projects DN 08-1/2016, and DN 08-20/2016 of National Science Foundation of Bulgarian Ministry of education and science as well as by project RD 08-142 of Shumen University. CvE acknowledges funding for the Stellar Astrophysics Centre, which is provided by The Danish National Research Foundation (Grant agreement no.: DNRF106). DM acknowledges support from the National Science Centre (NCN) grant no. 2016/21/B/ST9/01126. A part of this paper is the result of the exchange and joint research project >Spectral and photometric studies of variable stars> between the Polish and Bulgarian Academies of Sciences. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 730890. This material reflects only the authors views and the Commission is not liable for any use that may be made of the information contained therein. This research is based on (1) data obtained at the 1.5m telescope of the Sierra Nevada Observatory (Spain), which is operated by the Consejo Superior de Investigaciones Cientificas (CSIC) through the Instituto de Astrofisica de Andalucia, (2) data collected with telescopes at the Rozhen National Astronomical Observatory, (3) observations made with the Liverpool Telescope operated on the island of La Palma by Liverpool John Moores University in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias with financial support from the UK Science and Technology Facilities Council, (4) observationsmade with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias, in the island of La Palma, and (5) observations obtained with telescopes of the University Observatory Jena, which is operated by the Astrophysical Institute of the Friedrich-Schiller-University.

Ultra-hot Jupiters (UHJs) are gas giants with very high equilibrium temperatures. In recent years, multiple chemical species, including various atoms and ions, have been discovered in their atmospheres. Most of these observations have been performed with transmission spectroscopy, although UHJs are also ideal targets for emission spectroscopy due to their strong thermal radiation. We present high-resolution thermal emission spectroscopy of the transiting UHJ KELT-20b/MASCARA-2b. The observation was performed with the CARMENES spectrograph at orbital phases before and after the secondary eclipse. We detected atomic Fe using the cross-correlation technique. The detected Fe lines are in emission, which unambiguously indicates a temperature inversion on the dayside hemisphere. We furthermore retrieved the temperature structure with the detected Fe lines. The result shows that the atmosphere has a strong temperature inversion with a temperature of 4900 ± 700 K and a pressure of 10−4.8−1.1+1.0 bar at the upper layer of the inversion. A joint retrieval of the CARMENES data and the TESS secondary eclipse data returns a temperature of 2550−250+150 K and a pressure of 10−1.5−0.6+0.7 bar at the lower layer of the temperature inversion. The detection of such a strong temperature inversion is consistent with theoretical simulations that predict an inversion layer on the dayside of UHJs. The joint retrieval of the CARMENES and TESS data demonstrates the power of combing high-resolution emission spectroscopy with secondary eclipse photometry in characterizing atmospheric temperature structures. © ESO 2022. ; F.Y. acknowledges the support of the DFG Research Unit FOR2544 "Blue Planets around Red Stars" (RE 1664/21-1). CARMENES is an instrument for the Centro Astronómico Hispano-Alemán (CAHA) at Calar Alto (Almería, Spain), operated jointly by the Junta de Andalucía and the Instituto de Astrofísica de Andalucía (CSIC). CARMENES was funded by the Max-Planck-Gesellschaft (MPG), the Consejo Superior de Investigaciones Científicas (CSIC), the Ministerio de Economía y Competitividad (MINECO) and the European Regional Development Fund (ERDF) through projects FICTS-2011-02, ICTS-2017-07-CAHA-4, and CAHA16-CE-3978, and the members of the CARMENES Consortium (Max-Planck-Institut für Astronomie, Instituto de Astrofísica de Andalucía, Landessternwarte Königstuhl, Institut de Ciències de l'Espai, Institut für Astrophysik Göttingen, Universidad Complutense de Madrid, Thüringer Landessternwarte Tautenburg, Instituto de Astrofísica de Canarias, Hamburger Sternwarte, Centro de Astrobiología and Centro Astronómico Hispano-Alemán), with additional contributions by the MINECO, the Deutsche Forschungsgemeinschaft through the Major Research Instrumentation Programme and Research Unit FOR2544 "Blue Planets around Red Stars", the Klaus Tschira Stiftung, the states of Baden-Württemberg and Niedersachsen, and by the Junta de Andalucía. Based on data from the CARMENES data archive at CAB (CSIC-INTA). We acknowledge financial support from the Agencia Estatal de Investigación of the Ministerio de Ciencia, Innovación y Universidades and the ERDF through projects PID2019-109522GB-C51/2/3/4, PGC2018-098153-B-C33, AYA2016-79425-C3-1/2/3-P, ESP2016-80435-C2-1-R and the Centre of Excellence "Severo Ochoa" and "María de Maeztu" awards to the Instituto de Astrofísica de Canarias (SEV-2015-0548), Instituto de Astrofísica de Andalucía (SEV-2017-0709), and Centro de Astrobiología (MDM-2017-0737), and the Generalitat de Catalunya/CERCA programme. T.H. and P.M. acknowledge support from the European Research Council under the Horizon 2020 Framework Program via the ERC Advanced Grant Origins 83 24 28. N.C. and A.S.L. acknowledge funding from the European Research Council under the European Union's Horizon 2020 research and innovation program under grant agreement no. 694513. ; Peer reviewed

The individual pension funds not only complementary to public pension systems but also an important tool in order to meet the long-term funding needs of economies. Although not having a long history, the individual pension fund system, which has been practiced in various countries around the world for many years, has become one of the important elements of the economy in Turkey since October 27, 2003. The individual pension fund system is managed by private insurance companies and monitored by government authorities in Turkey. Therefore, these funds must be well managed and their performances should be closely monitored by either investors or governments in terms of contribution to economic progress. In this paper, the performance ratios of each individual pension funds and the pension fund companies' performances were analyzed for the 2010-2016 period. Due to the new individual pension funds are comprised of different research periods, we created 4 different research sample windows (2010- 2016; 2011-2016; 2012-2016; 2013-2016), in order to understand the performance of the pension fund companies. In the analyses, Sharpe, Sortino ratios, Treynor, Jensen indexes, and M2 performance measure are calculated for each individual pension fund based on research sample windows. In order to comprehend performances of the companies, the performance ratios of funds are clustered into two groups as positive and negative, and then the averages of both clusters are calculated for 11 different private pension fund companies. Within the scope of this study, 146 individual pension funds held by 11 pension fund companies were used and the pension funds daily return data gathered from The Capital Markets Board's database. The daily riskfree rate and market return data obtained from Bloomberg data terminal. The conclusion of the study reveals that all techniques illustrate similar results according to averaged positive and averaged negative performance ratios for each research sample window. The results of positive averages show that AVIVA and VAKIF outperformed other companies.

The individual pension funds not only complementary to public pension systems but also an important tool in order to meet the long-term funding needs of economies. Although not having a long history, the individual pension fund system, which has been practiced in various countries around the world for many years, has become one of the important elements of the economy in Turkey since October 27, 2003. The individual pension fund system is managed by private insurance companies and monitored by government authorities in Turkey. Therefore, these funds must be well managed and their performances should be closely monitored by either investors or governments in terms of contribution to economic progress. In this paper, the performance ratios of each individual pension funds and the pension fund companies' performances were analyzed for the 2010-2016 period. Due to the new individual pension funds are comprised of different research periods, we created 4 different research sample windows (2010- 2016; 2011-2016; 2012-2016; 2013-2016), in order to understand the performance of the pension fund companies. In the analyses, Sharpe, Sortino ratios, Treynor, Jensen indexes, and M2 performance measure are calculated for each individual pension fund based on research sample windows. In order to comprehend performances of the companies, the performance ratios of funds are clustered into two groups as positive and negative, and then the averages of both clusters are calculated for 11 different private pension fund companies. Within the scope of this study, 146 individual pension funds held by 11 pension fund companies were used and the pension funds daily return data gathered from The Capital Markets Board's database. The daily riskfree rate and market return data obtained from Bloomberg data terminal. The conclusion of the study reveals that all techniques illustrate similar results according to averaged positive and averaged negative performance ratios for each research sample window. The results of positive averages show that AVIVA and VAKIF outperformed other companies.

The individual pension funds not only complementary to public pension systems, but also an important tool in order to meet the long-term funding needs of economies. Although not having a long history, the individual pension fund system, which has been practiced in various countries around the world for many years, has become one of the important elements of the economy in Turkey since October 27, 2003. The individual pension fund system is managed by private insurance companies and monitored by government authorities in Turkey. Therefore, these funds must be well managed and their performances should be closely monitored by either investors or governments in terms of contribution to economic progress. In this paper, the performance ratios of each individual pension funds and the pension fund companies' performances were analyzed for 2010-2016 period. Due to the new individual pension funds are comprised by different research periods, we create 4 different research sample windows (2010-2016; 2011-2016; 2012-2016; 2013-2016), in order to understand the performance of the funds. In the analyses, Sharpe, Sortino ratios, Treynor, Jensen indexes, and M2 performance measure are calculated for each individual pension fund based on research sample windows. Afterwards, each performance ratio measurement is averaged to understand the financial performances of 11 different private pension fund companies. Within the scope of this study, 146 individual pension funds held by 11 pension fund companies were used and the pension funds daily return data gathered from The Capital Markets Board's database. The daily risk-free rate and market return data obtained from Bloomberg data terminal. The conclusion of the study reveals that, all performance indicators, except Jensen index, illustrate the same results in terms of ranking the private pension fund companies for each research sample window. However, as the research sample window varies, the rankings of the private pension fund companies also differ. For instance, when we focus on the 2010-2016 research sample window; Vakıf Emeklilik has the highest average performance ratio, whereas in 2013-2016 research sample window, it is being ranked as the third highest performance.

In Turkey, there are two types of pension fund systems. One of them is general social security system which the fund is managed by formal government institutions. The other one is individual pension fund system that the fund is managed by private insurance companies. Individual pension fund system in Turkey, not only serves to social security reform but also has an important role in the development of the financial system since October 27, 2003. Every private insurance company has their own pension fund types that investors may choose them and create their portfolios. Although there are many studies to measure the performances of the pension funds in the literature, such as Sharpe Ratio, Treyner Ratio, etc. It is well known that those performance ratios focus on the risk-free rates and the market indexes as a benchmark to measure the performance of funds as well as pension fund companies. In this study, we propose a new approach to measure pension fund companies' performances by presenting a new benchmark namely the efficient frontier generated by all individual pension funds. In this paper, to measure the performance of pension fund companies, all individual pension funds are grouped in terms of their own companies and created optimal portfolios for different levels of risks i.e. efficient frontiers. Then efficient frontier of each company is compared to the benchmark efficient frontier. According to the comparison of efficient frontiers, the companies' performances are discussed from the closest to the most distant. Within the scope of this study, 176 individual pension funds from 16 pension fund companies were used and the pension funds daily return data gathered from The Capital Markets Board's database for the period of 2006 – 2016. The analyses based on seven research sample windows which contains different time periods for comparing the efficient frontiers (2006-2016; 2007-2016; 2008-2016; 2009-2016; 2011-2016; 2012-2016; 2013-2016). It is concluded that according to the widest three sample windows, Anadolu Hayat Emeklilik portfolio has the closest efficient frontier to benchmark efficient frontier (2006-2016; 2007-2016; 2008-2016). On the other hand, while sample windows narrowed, Avivasa Emeklilik ve Hayat portfolio and Allianz Hayat ve Emeklilik portfolio have the closest to the benchmark efficient frontier (2009-2016; 2011-2016; 2012-2016; 2013-2016). As a result, considering the over eight years' performances, Anadolu Hayat Emeklilik portfolio has the highest returns. On the other hand, according to the less than eight years' performances, Avivasa Emeklilik ve Hayat and Allianz Hayat ve Emeklilik portfolios have the highest returns.

Risk assessments for carcinogens are being developed through an accelerated process in California as a part of the state's implementation of Proposition 65, the Safe Drinking Water and Toxic Enforcement Act. Estimates of carcinogenic potency made by the California Department of Health Services (CDHS) are generally similar to estimates made by the U.S. Environmental Protection Agency (EPA). The largest differences are due to EPA's use of the maximum likelihood estimate instead of CDHS use of the upper 95% confidence bounds on potencies derived from human data and to procedures used to correct for studies of short duration or with early mortality. Numerical limits derived from these potency estimates constitute "no significant risk" levels, which govern exemption from Proposition 65's discharge prohibition and warning requirements. Under Proposition 65 regulations, lifetime cancer risks less than 10−5 are not significant and cumulative intake is not considered. Following these regulations, numerical limits for a number of Proposition 65 carcinogens that are applicable to the control of toxic discharges are less stringent than limits under existing federal water pollution control laws. Thus, existing federal limits will become the Proposition 65 levels for discharge. Chemicals currently not covered by federal and state controls will eventually be subject to discharge limitations under Proposition 65. "No significant risk" levels (expressed in terms of daily intake of carcinogens) also trigger warning requirements under Proposition 65 that are more extensive than existing state or federal requirements. A variety of chemical exposures from multiple sources are identified that exceed Proposition 65's "no significant risk" levels.