Risk-return performances of real estate investment funds in Turkey including the Covid-19 period

The purpose of this research is to give an insight into the Turkish real estate investment funds (T-REIFs) by comparing their risk-return performances with the main benchmark investment tool Istanbul Stock Exchange-100 (BIST-100) Index. This study evaluated the performance of T-REIFs in four different periods between January 2017 and December 2020 (2017m1–2017m12, 2018m1–2018m12, 2019m1–2019m12 and 2020m1–2020m12) including the Coronavirus Disease (Covid-19) period by applying the Sharpe and Treynor ratios. In a well-diversified portfolio both ratios give the same results, but in the presence of non-systematic risk and the portfolio is poorly diversified, the Treynor ratio is a better indicator than the Sharpe ratio. The findings of this study show that rankings of Sharpe and Treynor ratios may differ for each period. These results also support the fact that the portfolios of funds in the Turkish real estate market are not well diversified. By providing corporate tax exemptions, and by enabling the investors to diversify their investments and reduce their risks, real estate investment funds are important alternatives to direct real estate investments in Turkey. In that context, being one of the pioneer studies in this niche and a new topic in emerging markets, analyzing the return performances of T-REIFs and comparing them with the returns of the BIST-100 index is aimed to contribute to literature as well as provide insight to investors who may consider investing in the Turkish real estate capital market instruments

Corneal melanosis successfully treated using topical mitomycin-C and alcohol corneal epitheliectomy: a 3-year follow-up case report

ABSTRACTWe report a case of primary acquired corneal melanosis without atypia associated with corneal haze in a patient with a history of limbal malignant melanoma and the effect of mitomycin-C. A 75-year-old woman with a history of limbal malignant melanoma presented with loss of vision in right eye. Corneal examination showed a patchy melanotic pigmentation with a central haze. Topical mitomycin-C improved visual acuity and corneal haze. However, the pigmented lesions persisted, and they were removed with alcohol corneal epitheliectomy. Histopathological examination demonstrated primary acquired melanosis without atypia. The lesions were successfully removed, and there were no recurrences during the follow-up period of 36 months. The association of conjunctival and corneal melanosis without atypia is a rare condition. In addition, co-existence of central corneal haze and melanosis may decrease visual acuity. Topical mitomycin-C and alcohol corneal epitheliectomy can be useful treatments in this condition

Comparison of Retrograde Intrarenal Surgery and Percutaneous Nephrolithotomy in the Treatment of 2-3 cm Multicalyceal Kidney Stones

Objective:To demonstrate the feasibility of retrograde intrarenal surgery (RIRS) in the treatment of 2-3 cm multicalyceal kidney stones considering the possible complications and unsuitable situations. Multiple kidney stones are observed among 20-25% of patients seen in urology clinics. Percutaneous nephrolithotomy (PNL) is the primary method for treating kidney stones larger than 2 cm. Despite the high success rate achieved, life-threatening complications associated with PNL may arise. Multiple accesses may be required for multiple stones. RIRS has become increasingly widely used. In our study, we aimed to compare these two methods in the treatment of 2-3 cm multicalyceal stones.Materials and Methods:We retrospectively evaluated data of patients who presented with multicalyceal kidney stones measuring 2-3 cm between 2012 and 2016. A total of 64 patients who underwent surgery (36 RIRS, 28 PNL) were included in the study.Results:Major complications were more common, operative time, fluoroscopy time and length of hospital stay time were longer in PNL group than in RIRS group. The number of stones was statistically higher in RIRS group. There was no statistically significant difference in other parameters. No statistically significant difference was found between the two groups in operation success rates.Conclusion:In the literature, the primary treatment option for 2-3 cm multicalyceal stones has been reported to be PNL. RIRS should be used in appropriate patients who have risks of complications related to anesthesia, bleeding disorder and patients with anatomic abnormalities who are not suitable for PNL. This method is also used to reduce the potential complications and it is more reliable

Relationship Between Ocular Surface Disease Index, Dry Eye Tests, and Demographic Properties in Computer Users

Objectives: The aim of the present study is to evaluate the ocular surface disease index (OSDI) in computer users and to investigate the correlations of this index with dry eye tests and demographic properties. Materials and Methods: In this prospective study, 178 subjects with an age range of 20-40 years and who spent most of their daily life in front of the computers were included. All participants underwent a complete ophthalmologic examination including basal secretion test, tear break-up time test, and ocular surface staining. In addition, all patients completed the OSDI questionnaire. Results: A total of 178 volunteers (101 female, 77 male) with a mean age of 28.8±4.5 years were included in the study. Mean time of computer use was 7.7±1.9 (5-14) hours/day, and mean computer use period was 71.1±39.7 (4-204) months. Mean OSDI score was 44.1±24.7 (0-100). There was a significant negative correlation between the OSDI score and tear break-up time test in the right (p=0.005 r=-0.21) and the left eyes (p=0.003 r=-0.22). There was a significant positive correlation between the OSDI score and gender (p=0.014 r=0.18) and daily computer usage time (p=0.008 r=0.2). In addition to this, there was a significant positive correlation between the OSDI score and ocular surface staining pattern in the right (p=0.03 r=0.16) and the left eyes (p=0.03 r=0.17). Age, smoking, type of computer, use of glasses, presence of symptoms, and basal secretion test were not found to be correlated with OSDI score. Conclusions: Long-term computer use causes ocular surface problems. The OSDI were found to be correlated with tear break-up time test, gender, daily computer usage time, and ocular surface staining pattern in computer users. (Turk J Ophthalmol 2014; 44: 115-8