Seasonal zooplankton community variation in Karatas Lake, Turkey

This study was carried out to determine seasonal variation and zooplankton community structure in Karataş Lake, Southern Turkey. Zooplankton samples were collected seasonally between 2002 and 2003 in two stations using a zooplankton net of 55-µm mesh size. A total of 42 taxa were identified, including 19 taxa (45.2 %) Rotifera, 16 taxa (38.1 %) Cladocera, and 7 taxa (16.7 %). Copepoda. Among them, Keratella quadrata, Asplanchna priodonta from Rotifera, Daphnia longispina, Ceriodaphnia quadrangula, Chydorus sphaericus, Coranatella rectangula from Cladocera, and Eudiaptomus drieschi, Eucyclops speratus from Copepoda were dominant species. Spring and autumn seasons were found to be the most similar by using Sorenson index value

Effect of singular vegetative elements on open channel flow characteristics

Son yirmi yıldır artan çevre bilinci ile birlikte akarsu yatağındaki bitkilerin akım alanı üzerine etkisini araştıran çalışmalara olan ilgi oldukça artmıştır. Farklı türde bitki topluluklarının akım alanı üzerine etkisini araştıran pek çok araştırma yapılmış olmasına rağmen geniş gövdeli tekil ağaçlar gibi bitki türlerinin akım alanı üzerine etkisi henüz yeterince anlaşılmış değildir. Bu çalışmada bir akım ortamındaki tekil doğal bitkilerin akımın hız ve türbülans karakteristikleri üzerine etkisini araştırmayı amaçlayan iki boyutlu deneyler gerçekleştirilmiştir. Deneylerin tamamı 26 m uzunluğunda, 0.98 m genişliğinde ve 0.85 m derinliğindeki akım kanalında gerçek bitki fidanları kullanılarak gerçekleştirilmiştir. Taşkın yataklarında sıkça rastlanan bu doğa olayını analiz etmek amacıyla, geniş gövdeli ağaçlar hacim yükseklik değişimleri gözönüne alınarak başlıca üç sınıfa ayrılmıştır. Hız ölçümlerinde üç adet akustik Doppler hız ölçer kullanılmıştır. Analiz aşamasında akım doğrultusundaki ve düşeydeki zamansal ortalama hız bileşenleri, akım doğrultusundaki ve düşeydeki türbülans bileşenleri ve türbülans kinetik enerjileri araştırılmıştır. Buna ilave olarak bitkinin mansab tarafında, bitkiden belirli bir mesafede, bitkinin yapısal özelliklerinin bir fonksiyonu olarak hız profilini veren bir eşitlik elde edilmiştir. Elde edilen eşitliğin geçerliliği deney verileri aracılığı ile sınanmıştır. Ayrıca, deneyler sonucunda geçirimli yapılarına rağmen akım ortamındaki bitkilerin akımı kayda değer ölçüde etkilediği ve neden oldukları türbülans ile önemli miktarda enerjiyi kırdıkları görülmüştür. Anahtar Kelimeler: Açık kanal, hidrolik, bitki, taşkın yatağı, hız profili.In the last two decades with the increasing environment awareness there is a growing interest on studies which attempt to understand the impact of vegetation on flow field in river and flood plain systems. Although in the past great attention has been devoted to explore the impact of vegetation community on flow pattern, the effect of singular vegetative element, such as trees with large trunk, on flow and turbulence pattern is not yet known. The primary aim of the study was to explore the impact of presence of natural singular vegetative elements (trees with large trunk) in flood plains on velocity and turbulence characteristics. In order to achieve the objective stated above two dimensional experimental measurements were conducted in controlled laboratory conditions. All the experiments were performed in the flume, which is capable of supplying steady flow and regular wave, located in Hydraulic Laboratory of Istanbul Technical University. The size of the flume is 26 m in length, 0.98 m in width and 0.85 m in depth.  Tree saplings were utilized to represent the vegetative effect on flow field. In order to analyze this commonly observed nature phenomenon, trees with large trunk were classified into three groups on the basis of their volume versus height relation. The primary difference between those introduced three types was the volume increment gradient along the height. For given successive height intervals, the volume of vegetation pertain to any interval is always larger than the volume of the interval belong to the one closer to bed for Type 1, approximately constant for Type 2, smaller for Type 3. In nature, since each species is unique in terms of architectural and structural properties, three representative species were selected which could characterize those three types mentioned above. Those selected species were Pinus Pinea, Thuja Orientalis, and Cupressus Macrocarpa for Type 1, Type 2 and Type 3, respectively. Throughout the velocity measurements three Acoustic Doppler Velocimeters, two with maximum 200 Hz sampling frequency, one with maximum 25 Hz sampling frequency, were employed. During the data analysis in order to further understand of the impact of presence of vegetation on flow, the time averaged velocity and turbulence kinetic energy characteristics were examined. The experiments that aim to examine the  More specifically, the experiments on velocity profile measurements along the flume were planned to be run for the combination of 2 depth values, 5 discharge values and 3 vegetation species. At the 10 locations velocity profiles were obtained by measurements along the centerline of the flume at the downstream of vegetation. In overall, 15 velocity profiles were acquired for each test condition. At the design stage of some water resources projects, estimating the flow conditions in open channels with an adequate accuracy is important. However, the gap was detected in the literature that there is still no any method or formulation which gives the velocity profile at the downstream of vegetation depending on the vegetative characteristics. In this context, it was considered that generating a formulation which gives the velocity profile at the downstream of vegetation is necessary for river engineers. Based on these facts a formulation which gives the velocity profile at a certain distance from vegetation was introduced. The validity of the proposed formulation was tested with experimental data for verification. It was seen that the velocity results obtained by introduced formulation are in well agreement with the experimental data. It should be kept in mind that the formulation is a function of vegetative characteristics such as volume, projected area, and submergence degree. Hence approximate calculation of the volume of related vegetation in the field with acceptable accuracy is crucial for the success of the application. The similarity between whole vegetation and its branch of related vegetation can be employed as a reference during the calculation of volume of vegetation. Experimental findings revealed that despite their porous structures, the presence of vegetation considerably disturbs the flow field and dissipate a remarkable amount of energy by turbulence. Furthermore experiments showed that sub-canopy flow occurs for three types of vegetation at the downstream of vegetation in the region close to bed. With increasing compactness of vegetation the magnitude of sub-canopy flow increases. In overall assessment it was concluded that presence of any type of tree with large trunk leads to 0-70 % extra sub-canopy flow at the bottom; 30-110 % retaining effect in the region close to the water surface.Keywords: Open channel, hydraulics, vegetation, flood plain, velocity profile

Different experimental approaches in modelling cataractogenesis: An overview of selenite-induced nuclear cataract in rats

Cataract, the opacification of eye lens, is the leading cause of blindness worldwide. At present, the only remedy is surgical removal of the cataractous lens and substitution with a lens made of synthetic polymers. However, besides significant costs of operation and possible complications, an artificial lens just does not have the overall optical qualities of a normal one. Hence it remains a significant public health problem, and biochemical solutions or pharmacological interventions that will maintain the transparency of the lens are highly required. Naturally, there is a persistent demand for suitable biological models. The ocular lens would appear to be an ideal organ for maintaining culture conditions because of lacking blood vessels and nerves. The lens in vivo obtains its nutrients and eliminates waste products via diffusion with the surrounding fluids. Lens opacification observed in vivo can be mimicked in vitro by addition of the cataractogenic agent sodium selenite (Na2SeO3) to the culture medium. Moreover, since an overdose of sodium selenite induces also cataract in young rats, it became an extremely rapid and convenient model of nuclear cataract in vivo. The main focus of this review will be on selenium (Se) and its salt sodium selenite, their toxicological characteristics and safety data in relevance of modelling cataractogenesis, either under in vivo or in vitro conditions. The studies revealing the mechanisms of lens opacification induced by selenite are highlighted, the representatives from screening for potential anti-cataract agents are listed

Blended learning experience in a programming language course and the effect of the thinking styles of the students on success and motivation

High-level thinking and problem solving skill is one requirement of computer programming that most of the students experience problems with. Individual differences such as motivation, attitude towards programming, thinking style of the student, and complexity of the programming language have influence on students’ success on programming. Thus, curriculums and learning environments should be designed in order to support students’ learning attempts and willingness to achieve the goals of the course. Blended learning is one of the educational approaches that used in Information and Communication Technology (ICT) courses in order to ease the learning process. In this manner, the purpose of this study is to investigate the effect of blended learning approach, consisted be blending face-to-face and e-learning approaches, on academic success and motivations of students with different learning styles in a programing language course. Results of the study showed that courses supported with online learning tools has a positive effect on students’ motivation, and correspondingly has a positive effect on academic success. In addition, the results revealed that introvert students need online learning tools more than others. Furthermore, it was found that thinking styles have an effect on motivation and academic success. Eventually, using blended learning approach in a programming language course has a positive effect of students’ motivation, academic success and satisfaction. © The Turkish Online Journal of Educational Technology

Effect of information technologies (It) pre-service teachers’ learning approaches on their attitude towards programing

It has been widely debated issue in the literature that learning programming requires students to have advanced thinking skills to be successful in programming. Having a negative attitude towards programming is considered as one of the important reasons which cause students to fail in programming. The relationship among students’ way of learning programming, their study approaches and their success in programming has not been explored in the literature in detail yet. In this regard, the purpose of the present study is to determine IT preservice teachers’ learning styles and their attitude of towards computer programming; and to investigate their relationship. It was determined that whereas IT preservice teachers’ year at the university exhibits significant difference with respect to their attitude towards programming; no significant relationship is found between their gender and types of their previous high school. However, it was observed that vocational high school graduates were more inclined toward programming compared to students graduated from other types of high schools. Additionally, it was found that most IT preservice teachers preferred deep studying approach the most effective way of comprehension of education materials since it uses the most effective learning strategy. Another positive correlation was determined between approaches of preservice teachers towards deep studying and their attitude towards programming. © The Turkish Online Journal of Educational Technology

Efficiency and tendency of the educational computer games in education: A document review

The computer and internet technologies which show an immediate change and development, show its effect in educational field as well as all fields of life. One of the implementation areas of computer and internet technologies is the computer games. While the computer games provide recreational time to the users, it may provide environments for learning some information. Particularly, the usage of the computer games which the school-age children like every much and play without getting bored in education, is an important matter to be considered. The purpose of this study is to determine the efficiency and integration process of the educational computer games to educational environments on the basis of literature by reviewing within the frame of the performed studies. Therefore, 45 thesis and articles including the scientific studies and the educational computer games till 2015, have been analyzed with the document analysis method. It is found in the document analysis that educational computer games have positive results nearly in all studies. It is observed that it has positive effects on the academic successes, problem solving skills, motor skills and attitude, affective specifications like motivation and self-efficiency of the students. © The Turkish Online Journal of Educational Technology

Kırıkkale'deki Köpeklerde Mikrokültür Yöntemi ve IFAT ile Visseral Leishmaniosisin Prevalansinin Araştirilmasi.

PubMed: 20340078This study was carried out in order to compare the seroprevalence of visceral leishmaniasis in dogs from different areas of Kirikkale between 2006-2008 using the microculture method (MCM) which is a new method, and the indirect fluorescent antigen test (IFAT). All of the blood collected from total of 50 dogs was found to be negative by MCM. Only one male Beagle strain dog (3 years old) was found to be seropositive at 1/128 titers (2%) for anti-Leishmania infantum IgG antibodies by IFAT

Reaction of peach and nectarine rootstocks to different populations of root-knot nematode species, Meloidogyne incognita (Kofoid & White, 1919) and Meloidogyne javanica (Treub, 1885)1 [Şeftali ve nektarin anaçlarının, Kök ur nematodu türleri; Meloidogyne incognita (Kofoid & White, 1919) ve Meloidogyne javanica (Treub, 1885)’nın farklı popülasyonlarına karşı reaksiyonu]

The reaction of peach and nectarine rootstocks, Garnem, Cadaman, GF 677, Barrier, Nemaguard and M-29, used in Turkey was investigated to five populations of root knot nematode species, Meloidogyne incognita (Kofoid & White, 1919) and Meloidogyne javanica (Treub, 1885), under controlled conditions. The study was conducted at the Plant Protection Central Research Institute of the Laboratory of Nematology (Republic of Turkey Ministry of Agriculture and Forestry) in 2013-2016. Three M. javanica (TR16-2, TR12-1 and S5-1) and two M. incognita (TR10-3, S4-1) populations were obtained from infested peach orchards and established pure culture. All rootstocks were inoculated with 3000 second stage juveniles (J2s) from each a population. Each combination was replicated five times. One hundred and twenty d after inoculation, the ratio of galling on the roots and the number of nematode J2s in the soil were assessed and thus the response of rootstocks was determined. M-29, Cadaman and Garnem rootstocks were resistant to all populations, whereas GF 677 was susceptible to all populations. Nemaguard was resistant to TR16-2 and TR12-1 populations, but this rootstock was susceptible to S5-1, TR10-3 and S4-1 populations. Barrier rootstock was moderately resistant to TR16-2 and TR12 populations but susceptible to S5-1 and S4-1 populations. The findings could be used for control root-knot nematodes as well in breeding programs. © 2019 Entomological Society of Turkey. All rights reserved

On the second homology of the schützenberger product of monoids

For two finite monoids S and T, we prove that the second integral homology of the Schützenberger product S{lozenge, open}T is equal to H2(S{lozenge, open}T) = H2(S) x H2(T) x (H1(S) ?Z H1(T)) as the second integral homology of the direct product of two monoids. Moreover, we show that S{lozenge, open}T is inefficient if there is no left or right invertible element in both S and T