Preliminary study on otolith chemistry and otolith morphology of two demersal fish species, European hake Merluccius merluccius (Linnaeus, 1758) and striped red mullet (Mullus surmuletus, Linnaeus, 1758) in the Sea of Marmara

Otoliths are calcium carbonate (CaCO3) accumulations. Under the influence of different ecosystems morphological and chemical composition change. In this study, economically important two demersal fish species; European hake Merluccius merluccius (Linnaeus, 1758) and Stripet red mullet (Mullus surmuletus Linnaeus, 1758) was examined. Otoliths (Sagitta) belonging to these two species have been studied both chemically and morphologicall. Morphometric measurements of otoliths (length, mm; width, mm; area, mm2; perimeter, mm) in the sagittal of each species was made by the Leica M125 tri-ocular microscope. In the chemical analysis of otoliths, strontium (Sr), magnesium (Mg) and calcium (Ca) trace element amounts, the ratios of Sr and Mg trace elements to Ca element (Sr/Ca and Mg/Ca) were determined. For the micro-chemical analysis of otoliths ICP-MS was used. The highest magnesium (24.92±9.57 mmol/mol) and strontium (26.17±1.81 mmol/mol) element values were found in the otolith of red mullet. The difference between strontium (Sr) and magnesium (Mg) amounts for two fish species was found to be significant (P<0.05). In addition to it was found that the difference between them in the amount of calcium is significant (P<0.001). The shape indexes of otoliths are significantly different between the two fish species. Especially in terms of roundness (RD) and aspect ratio (AR) (P<0.001). The results of this study provide information about the habitats of two economic importance demersal fish species. Since such studies can give information about the habitat areas of fish species, they are important for tracking stocks, migration routes and sustainable fisheries.

Health service delivery for type 1 diabetes during the lockdown in Uganda following the coronavirus disease 2019 pandemic

Lockdown measures to reduce the spread of coronavirus disease 2019 (COVID-19), may adversely impact on diabetes supplies and metabolic control, especially in type 1 diabetes in low-resource countries. To address this, we conceptualized a service delivery model that incorporated a digitized tool. The digitized tool (UT1D-HIMAS) maintained electronic health records, monitored clinic supplies, patient clinic visits and admissions, and sent automated SMS messages. Delivery of supplies was by motor vehicles, motorcycles, bicycles or patients/caregivers walking to clinics. Metabolic control was assessed by glycated haemoglobin (HbA1c). Monitoring of clinic supplies including emergency restocking, patient clinic visits and admissions, and sending automated SMS by UT1D-HIMAS were successfully achieved. A fall in clinic visits, reaching a nadir (67.9%) in May 2020 was observed. HbA1c (mean ± SD mmol/mol) significantly (p= 0.040) worsened from 79.1 ± 26.8 to 94.9 ± 39.2 and (p=0.002) from 67.1 ± 22.7 to 84.8 ± 39.4 in the rural and urban clinic respectively. The digitized health information system exhibited high practicability in tracking stocks, clinic visits and hospitalisation but failed to improve metabolic control.

Ex-post stock return behaviour of corporate restructurings and corporate control

Purpose This paper aims to investigate the correlation between stock returns of the parent and newly created entity and the degree of return skewness in parents in the three different corporate restructurings. Design/methodology/approach Using a sample of spin-offs, equity carve-outs and tracking stocks, ordinary least squares regression is used to test the relationship between stock return correlation as well as stock return skewness and the type of corporate restructurings. Findings Tracking stock offering has the largest correlation in stock returns, whereas spin-off has the least correlation in stock returns. Also, the result from the skewness test is not consistent with the hypothesis that the stock returns skewness is positively related to the degree of ownership and control. Originality/value This is one of the few papers looking at the three corporate restructurings and their return skewness.

ELS Hedging Method based on CVaR Using Stocks Portfolio and Futures

In this paper, we analyze the hedging risk intrinsic in the auto call step down equity linked securities (ELS) based on two underlying indices including HSCEI, which are major products of the ELS market. And we also propose new hedging strategies based on Conditional Value at Risk (CVaR) using stocks portfolio and futures. Due to the non-symmetric bimodal distribution for return of ELS, which comes from the Knock-In (KI) property inherent in step down ELS structure, and inherent shortfall risk in the ELS structure, a local delta hedging strategy has a limit. In addition, hedging using futures are difficult because of 1) frequent roll-over related with HSCEI futures, 2) price difference between underlying index and futures and 3) lack of futures liquidity caused by excessive ELS issue based on HSCEI. As a way to manage these problems, this paper proposes new hedging strategies : First, construct stocks portfolio tracking index using method suggested by Rockafellar and Uryasev (2002), Alexander, Coleman and Li (2006). Second, do hedging by using this stocks portfolio and futures. This paper shows that 1) index-tracking stocks portfolio based on CVaR has a better performance and lower shortfall risk than index by comparing market ratio, information ratio and Sharpe Ratio, and 2) hedging using stocks portfolio is better than futures. As the policy proposals, if ETF, which tracks the underlying indices of ELS based on CVaR, is to be listed on the exchange (KRX), various kinds of product structures for mid-risk-mid-return structured products will be able to develop further, as well as offer more convenience with hedging.