Volatility in Istanbul Stock Exchange

Author's OriginalSince economic agents make the decisions based on the perceived distribution of the random variables in the future, assessment and measurement of the variance has a significant impact on their course of action. Therefore, market participants’ ability to accurately measure and predict the stock market volatility has wide spread implications. This capability has a particular importance in an environment, where the perception of high levels of volatility has the potential to erode the investor confidence and divert the capital inflows from equity markets. This is a particular concern for the emerging equity markets that lack the advanced institutional and informational infrastructures and which are very vulnerable to domestic and foreign capital flows. The purpose of this study is to determine the time-varying characteristics of volatility in an emerging stock market by utilizing rich family of ARCH models. The primary focus of the study is to explore the nature of volatility in the ISE.Aybar, C. B. & Yvan, Z. A. (1998). Volatility in Istanbul Stock Exchange. ISE Review, 6(2)

Comparative analysis of the Mexican and Turkish currency crises

Author's OriginalThe study aims to explore characteristics of currency crises in emerging markets. Two recent experiences in Mexico and Turkey respectively analyzed carefully to identify common elements in the development and eruption of the crises. Results of the study suggest that there are several background factors and triggers that were consistent in both cases. Finally a discussion of the policy implications of the findings concludes the study.Aybar, C., Ajami, R., & Bear, M. (2000). Currency crises in emerging markets: A comparative analysis of the Mexican and Turkish cases. International Journal of Public Administration, 23(5-8), 963-1006

Karpal Tünel Sendromu Dekompresyon Cerrahisi Geçiren Hastaların Geç Dönem Memnuniyet Düzeylerini Değerlendirmede Elektromiyografi ve Hasta Değerlendirme Ölçümünün Geçerliliği

Objective: This study investigated whether electromyelography (EMG) evaluation is helpful in the late phase after surgical treatment of carpal tunnel syndrome (CTS). Methods: This retrospective study included 35 patients who underwent mini-open decompression therapy between 2008 and 2011 with CTS diagnosis. Patients were assessed electrophysiologically and clinically with Patient Evaluation Measurement (PEM) scoring and handgrip, palmar grip, lateral grip, and fingertip grip strength. Additionally, patients' clinical scores and strength values were compared with electrophysiologic values from preoperative and postoperative 4-year controls. Results: According to the Padua classification, EMG data were classified before and after surgery. One patient had extreme grade, four patients had severe grade, 26 patients had moderate grade, and four had a mild grade before surgery. At the postoperative 4th year EMG follow-up, six patients were classified as minimal and 29 as negative. According to the PEM scale, the mean score before surgery was 58.77±7.89, and in the controls at the 4th year after surgery, the mean score was 13.48±4.01. The strength of the operated hand was significantly weaker than that of the contralateral healthy hand before surgery. However, in the controls at the 4th year after surgery, the strength of the operated hand was significantly increased compared with the preoperative period, and there was no significant difference from the contralateral hand. Conclusion: Electrophysiological assessment (EMG) in the late phase after surgical treatment of CTS has positive parallels with clinical assessment and strength assessment. Therefore, we conclude that EMG helps follow late surgical outcomes. © Copyright 2022 by Medical Journal of Bakırköy published by Galenos Yayınev

Analysis of attitudes of Turkish citizens towards the effect of European Union membership on the economic, political, and cultural environment

Author's OriginalPrevious studies on Turkey’s possible accession to the European Union have mostly focused on the level of support for membership as expressed by Turkish citizens. The purpose of this paper is to shed some light on the specific expectations and perceptions of the Turks about the EU membership process, focusing on economic development, democratic progress, economic and political stability, and cultural influence. In both the focus group studies and the final survey, the authors targeted people who have some knowledge about the EU accession process and EU membership, namely, academics and business people.Aybar, C., Mergen, A., Perotti, V., & Reid, D. (2007). Analysis of Attitudes of Turkish Citizens towards the Effect of European Union Membership on the Economic, Political, and Cultural Environment. Turkish Studies, 8(3), 329-348. doi:10.1080/1468384070148908

Estudio preliminar de la fluctuación de Bemisia tabaci (Hemiptera: Aleyrodidae) en cultivos de tomate y pimiento bajo cubierta, Tucumán, Argentina

The aim of this study was to determine the abundance and population dynamics of Bemisia tabaci (Gennadius) in greenhouse tomato and pepper crops in Lules department, Tucumán province (Argentina). Entomological sampling was carried out from July 2008 to March 2009. Adults were collected through sticky traps while immature individuals were collected from the leaflets of the different plant strata. A total of 121.075 individuals of B. tabaci were collected, from which 12.630 corresponded to eggs, 8.718 to nymphs, 262 to pupae, and 99.465 to adults. In general terms, the abundance of B. tabaci increased considerably from the third week of sampling and stayed high, with pepper crops showing the highest number of individuals.El objetivo del trabajo fue determinar la abundancia y fluctuación poblacional de Bemisia tabaci (Gennadius) en cultivos de tomate y pimiento bajo cubierta en el departamento Lules, provincia de Tucumán (Argentina). Los muestreos entomológicos se realizaron desde julio de 2008 a marzo de 2009, recolectándose adultos mediante trampas adhesivas e inmaduros en los foliolos de los diferentes estratos de las plantas. Se recolectó un total de 121,075 individuos de B. tabaci, de los cuales 12,630 corresponden al estado de huevo, 8,718 a ninfa, 262 a pupa y 99,465 a adulto. En líneas generales, la abundancia de B. tabaci aumentó considerablemente a partir de la tercera semana de muestreo y se mantuvo elevada, siendo el cultivo de pimiento el que presentó mayor número de individuos

New records of predation on eggs of Bemisia tabaci (Hemiptera: Aleyrodidae) by Chrysopodes (Chrysopodes) Lineafrons (Neuroptera: Chrysopidae) in northwestern Argentina

Bemisia tabaci has become one of the major pests of economic importance that affects several crops worldwide. Among their natural enemies are found the Chrysopidae family, with larvae predators of different pests resulting very effective biological control agents. In order to contribute to possible use of this beneficial insect in B. tabaci biological control, the developmental time and survival of the immature stages of Chrysopodes (Chrysopodes) lineafrons was determined, as well as longevity and oviposition of the adults fed with eggs of B. tabaci. Chrysopodes (C.) lineafrons adults were collected in tomato crops in Lules department, Tucumán province. To determine the developmental duration for each instars and survival of the larvae, 90 eggs of C. (C.) lineafrons were randomly selected, of which only 71 eggs hatched; of these, 34 larvae were fed with B. tabaci eggs and 37 with Sitotroga cerealella eggs, used as control. The oviposition and longevity of the adults were recorded, both fed with the two preys. Chrysopodes (C.) lineafrons larvae consumed an average 127.04 (± 40.2) eggs of B. tabaci and 44 (± 19.04) eggs of S. cerealella per day. Mean developmental time of C. (C.) lineafrons fed with B. tabaci eggs was 45 (± 3.54) days and 35 (± 5.04) days with S. cerealella eggs. Survival of immature stages, number of eggs per adults and their longevity were higher when C. (C.) lineafrons were fed with S. cerealella eggs than with B. tabaci eggs. Chrysopodes (C.) lineafrons has proved to be an efficient predator which would represent an excellent tool for B. tabaci biological control in tomato crops.Bemisia tabaci se ha convertido en una de las principales plaga de importancia económica, afectando a diversos cultivos en todo el mundo. Entre sus enemigos naturales se encuentran las especies de la familia Chrysopidae, con larvas depredadoras de diferentes plagas que resulta un agente de control biológico muy efectivo de diferentes plagas. Para contribuir al posible aprovechamiento de este insecto benéfico en el control biológico de B. tabaci, se determinó el tiempo de desarrollo y supervivencia de los estadios inmaduros de Chrysopodes (Chrysopodes) lineafrons, y la longevidad y oviposición de los adultos alimentados con huevos de B. tabaci. Los adultos de C. (C.) lineafrons fueron recolectados en cultivos de tomate en el departamento Lules, provincia de Tucumán. Para determinar la duración del desarrollo de cada estadio y la supervivencia de las larvas, se seleccionaron aleatoriamente 90 huevos de C. (C.) lineafrons, de los cuales sólo 71 huevos eclosionaron; de estas, 34 larvas fueron alimentadas con huevos de B. tabaci y 37 con huevos de Sitotroga cerealella, utilizados como control. Se registró la oviposición y la longevidad de los adultos alimentados con las dos presas. Las larvas de C. (C.) lineafrons consumieron un promedio de 127,04 (± 40,2) huevos de B. tabaci y 44 (± 19,04) huevos de S. cerealella por día. El tiempo promedio de desarrollo de C. (C.) lineafrons alimentados con huevos de B. tabaci fue de 45 días (±3,54); mientras que los alimentados con huevos de S. cerealella fue de 35 días (± 5,04). La supervivencia de los estadios inmaduros, el número de huevos por adultos y la longevidad fue mayor cuando C. (C.) lineafrons fueron alimentados con huevos de S. cerealella que con los huevos de B. tabaci. Chrysopodes (C.) lineafrons demostró ser un depredador eficiente, representando así una excelente herramienta para el control biológico de B. tabaci en cultivos de tomate

Correction of more hallux valgus pathologic disorders with a single distal osteotomy a new surgical technique

Background: Hallux valgus, one of the most common deformities of the great toe, may cause pain, dysfunction, and impaired gait pattern. In this retrospective study we report the results of a new type of distal metatarsal osteotomy combined with distal soft-tissue release in patients with mild-to-moderate hallux valgus deformity. Methods: This new technique was used in the management of 32 feet of 31 patients (eight men and 23 women) with mild-to-moderate hallux valgus. Hallux valgus angle, i ntermetatarsal angl e, and distal metatarsal articular angl e were measured on preoperative, earl y postoperative (6–8 weeks), and l ate (1 year) postoperative radiographs. American Orthopaedic Foot and Ankle Society hallux metatarsophalangeal score was calculated. Sesamoid position, by considering medial sesamoid position, and metatarsal shortness were also measured. Results: Statistically significant differences were detected between the preoperative and late postoperative measurements of the hallux valgus angle, distal metatarsal articular angle, intermetatarsal angle, and sesamoid position parameters in patients operated on with this technique. Improvement was 14° for the hallux valgus angle, 4° for the distal metatarsal articular angle, and 4° for the intermetatarsal angle. Sesamoid position was also improved, and the mean American Orthopaedic Foot and Ankle Society score was significantly improved. Metatarsal shortness greater than 2 mm was observed in two patients without resulting in any clinical discomfort. Conclusions: This new technique was easy, safe, and promising in patients diagnosed as having mild-to-moderate hallux valgus deformity. © 2021, American Podiatric Medical Association. All rights reserved

A Grouping Harmony Search Algorithm for Assigning Resources to Users in WCDMA Mobile Networks

This paper explores the feasibility of a particular implemen- tation of a Grouping Harmony Search (GHS) algorithm to assign re- sources (codes, aggregate capacity, power) to users in Wide-band Code Division Multiple Access (WCDMA) networks. We use a problem for- mulation that takes into account a detailed modeling of loads factors, including all the interference terms, which strongly depend on the as- signment to be done. The GHS algorithm aims at minimizing a weighted cost function, which is composed of not only the detailed load factors but also resource utilization ratios (for aggregate capacity, codes, power), and the fraction of users without service. The proposed GHS is based on a particular encoding scheme (suitable for the problem formulation) and tailored Harmony Memory Considering Rate and Pitch Adjusting Rate processes. The experimental work shows that the proposed GHS algorithm exhibits a superior performance than that of the conventional approach, which minimizes only the load factors

The spatio-temporal distribution patterns of biting midges of the genus Culicoides in Salta Province, Argentina

The goal of this survey was to analyze the spatio-temporal distribution patterns of Culicoides Latreille species (Diptera: Ceratopogonidae) and their relationship with environmental variables in Salta, northwestern Argentina. Culicoides were collected monthly from January 2003 through December 2005. The influence of the climatic variables on population abundance was analyzed with a multilevel Poisson regression. A total of 918 specimens belonging to five species were collected. The most abundant species was Culicoides paraensis Goeldi (65.5%), followed by Culicoides lahillei Iches (14.6%) and Culicoides debilipalpis Lutz (7.6%). The highest seasonal abundance for C. paraensis, C. debilipalpis and C. lahillei occurred during the spring and summer. A Poisson regression analysis showed that the mean maximum and minimum temperature and the mean maximum and minimum humidity were the variables with the greatest influence on the population abundance of Culicoides species.Facultad de Ciencias Naturales y Muse

Prospection and identification of traditional-heritage Peruvian grapevine cultivars (Vitis vinifera L.) from Ica and Cañete valleys

Interest in ancient and autochthonous cultivars has increased in recent years since they are directly related to the historical and cultural values of a region. Ica and Cañete valleys (Peru) have a long history of grapevine cultivation and the aim of this study was to identify phenotypes corresponding to the most used varieties for the local production of Pisco and wine. The 29 samples were collected in 17 vineyards in the Ica and Cañete valleys, and were analyzed using 20 molecular markers and 5 morphological descriptors according to the OIV. Results showed that the 29 collected samples corresponded to 11 genotypes: seven traditional cultivars and four unknown genotypes not registered previously. The known cultivars were 'Muscat of Alexandria', 'Listán Prieto', 'Quebranta', 'Moscatel Rosado', 'Pedro Giménez', 'Muscat Hamburg' and 'Palomino Fino'. The four not registered genotypes are locally known as 'Mollar de Ica', 'Moscatel Rosada de Cañete', 'Prieta Mollar' and 'Torontel'. All of them correspond to offspring of traditional-heritage Peruvian cultivars. We also found a phenotypic variation of 'Listán Prieto' with muscat flavor and identified phenotypic berry color variations in 'Quebranta'. This study increases the knowledge of traditional Peruvian grape varieties and highlight the genetic variability preserved in the traditional vineyards of local producers