Investigating the Market Linkages between Cryptocurrencies and Conventional Assets

Many investors include cryptocurrencies as potential investment tools in their portfolios. Previous studies have mostly analyzed Bitcoin regarding its hedge and safe haven features. Although the cryptocurrency market has expanded far beyond Bitcoin, few studies have examined the interaction among all other cryptocurrencies and conventional financial assets. For this purpose, as the dependent variable, we included the cryptocurrency index to represent the cryptocurrency market, whereas international stocks, bonds, United States (US) dollars, gold, and commodities as independent variables in the analysis. The interactions among the variables were analyzed using the Granger causality tests. The analysis results revealed a two-way causality relationship between the cryptocurrency market and the bond markets, indicating that the cryptocurrency index can be used to predict bond prices and vice versa

Comparative Analysis of Vertebroplasty and Kyphoplasty for Osteoporotic Vertebral Compression Fractures

Study DesignA retrospective study.PurposeThe aim of this study is to compare the efficacy and outcome of vertebroplasty compared with unipedicular and bipedicular kyphoplasty for the treatment of osteoporotic vertebral compression fractures in terms of pain, functional capacity and height restoration rates.Overview of LiteratureThe vertebroplasty procedure was first performed in 1984 for the treatment of a hemangioma at the C2 vertebra. Kyphoplasty was first performed in 1998 and includes vertebral height restoration in addition to using inflation balloons and high-viscosity cement. Both are efficacious, safe and long-lasting procedures. However, controversy still exists about pain relief, improvement in functional capacity, quality of life and height restoration the superiority of these procedures and assessment of appropriate and specific indications of one over the other remains undefined.MethodsBetween 2004 and 2011, 296 patients suffering from osteoporotic vertebral compression fracture underwent 433 vertebroplasty and kyphoplasty procedures. Visual analogue scale (VAS), the Oswestry Disability Index (ODI) and height restoration rates were used to evaluate the results.ResultsMean height restoration rate was 24.16%±1.27% in the vertebroplasty group, 24.25%±1.28% in the unipedicular kyphoplasty group and 37.05%±1.21% in the bipedicular kyphoplasty group. VAS and ODI scores improved all of the groups.ConclusionsVertebroplasty and kyphoplasty are both effective in providing pain relief and improvement in functional capacity and quality of life after the procedure, but the bipedicular kyphoplasty procedure has a further advantage in terms of height restoration when compared to unipedicular kyphoplasty and vertebroplasty procedures

Is Placing Prophylactic Dural Tenting Sutures a Dogma?

Objective In this study, we investigated if and when dural tenting sutures are necessary during craniotomy. Methods Results from 437 patients aged 18 to 91 years (average, 43.5 years) who underwent supratentorial craniotomy between 2014 and 2019 were evaluated. The patients were categorized into 1 of 3 groups, patients who had at least 3 prophylactic dural tenting sutures placed before opening of the dura (group 1), at least 3 dural tenting sutures placed after surgery was completed, during closure (group 2), or no dural tenting sutures (group 3 [control]). All such sutures in groups 1 and 2 were placed in the circumference of the craniotomy and dural junction. No central dural tenting sutures were placed in any of the patients. Results Among the 437 patients, 344 underwent surgery for the first time and 93 were undergoing a second surgery. Cranial computed tomography imaging was performed for each patient 1 hour, 3 days, and 1 month after surgery. In group 1, 3 patients had a cerebral cortex contusion and 2 patients had acute subdural hematoma after the sutures were placed. In groups 2 and 3, none of the patients had a cerebral cortex contusion or acute subdural hematoma. Fewer complications were observed when dural tenting sutures were placed during postsurgical closure. Conclusion Placing dural tenting sutures is an important technique for ensuring hemostasis. However, when not needed, they seem to cause inadvertent complications. As our results suggest, knowing when and where to use them is equally important

Birkapılı hidroelektrik santraline ait ilave su depolama tesisinin fizibilitesi.

Climate change concerns, high oil prices and increasing government support are some of the driving reasons of increasing renewable energy legislation, incentives, and commercialization. Hydroelectricity is the most widely used form of renewable energy and refers to electricity generated by hydropower. In this study, a storage facility is proposed to store some additional water and increase the profitability of the existing Birkapılı Hydroelectric Power Plant. The storage facility is composed of a gravity dam and an uncontrolled spillway. With the help of the proposed storage facility, maximum utilization of the water is provided and shift of the electricity generation to peak demand periods becomes possible. Consequently, feasibility of the existing power plant is improved. A number of alternatives for a spillway are taken into account and the corresponding concrete gravity dam is designed. Stability analyses and operation studies are conducted using spreadsheets to achieve an economical solution.M.S. - Master of Scienc

Turning dilate from point tool into part of an instrument: an example of a preservice mathematics teacher working on a dynamic geometry system

International audienceThe aim of this paper is to investigate a preservice mathematics teacher’s instrumental genesis of ‘dilate from point’ tool in a dynamic geometry system. Data is collected through a series of task-based interviews including seven specific construction tasks regarding the use of dilate from point tool with a Turkish preservice mathematics teacher. Video-recorded interviews and screen recorder software productions were triangulated and analysed within the theoretical lens of instrumental genesis. According to the findings, the participant firstly explored the properties of the dilation transformation and its relation to other geometrical concepts and transformations. Secondly, the participant developed instrumented schemes related to the dilate from point tool for applying appropriate strategies in the construction tasks

Turning dilate from point tool into part of an instrument: an example of a preservice mathematics teacher working on a dynamic geometry system

International audienceThe aim of this paper is to investigate a preservice mathematics teacher’s instrumental genesis of ‘dilate from point’ tool in a dynamic geometry system. Data is collected through a series of task-based interviews including seven specific construction tasks regarding the use of dilate from point tool with a Turkish preservice mathematics teacher. Video-recorded interviews and screen recorder software productions were triangulated and analysed within the theoretical lens of instrumental genesis. According to the findings, the participant firstly explored the properties of the dilation transformation and its relation to other geometrical concepts and transformations. Secondly, the participant developed instrumented schemes related to the dilate from point tool for applying appropriate strategies in the construction tasks

EFFECT OF OUT-OF-AUTOCLAVE CURING ON THE BENDING STRENGTH OF TPNCF AND UNIDIRECTIONAL LAMINATES

Out-of-autoclave(ooA)treatments in composite manufacturing draw the attention ofmanufacturers anddesigners in aerospace industry by offering numerous advantages over the traditional autoclave processing. Besides, thin ply non crimp fabric (TPNCF) architecture is proven for improved delamination resistance and fracture toughness. The objective of the study is comparingthe bending strength of flat and curved beams of TPNCF [0/45] and Unidirectional (UD)[0/45] autoclaved andooA CFRP parts. The 4-point bending experiment results show that the selection of TPNCF architecture in complex geometries provides an improved strength for ooA specimens