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Metal bioaccumulation in selected tissues of barb (Barbus sp.) and common carp (Cyprinus carpio, Linnaeus 1758) from the Keban Dam Lake, Turkey.
No full textThe aquatic life has been negatively influenced by harmful effects of environmental toxic elements, including heavy metals. The elevated concentrations of metals may be harmful for aquatic animals and human health. Herein, the present study deals with assessment of the bioavailability of metals [cadmium (Cd), chrome (Cr), copper (Cu), zinc (Zn), iron (Fe), lead (Pb), manganese (Mn), mercury (Hg), nickel (Ni), and selenium (Se)] in organs such as muscle, gills, liver, kidney, and gonad of the commercially consumed Barbus sp. and Cyprinus carpio (Linnaeus, 1758) collected from Keban Dam Lake, eastern Turkey. The fish were captured from four different stations of Keban Dam Lake. Our results indicated that Fe and Zn concentrations were the highest in all tissues of two fish species while Cd concentrations were the lowest levels. In addition, detected metals accumulated in the muscle of common carp at higher levels compared to Barbus sp. The results from the present study also demonstrated significant variations and considerable differences in the concentrations of all 10 elements between the four stations and different fish tissues. Overall, the concentrations of detected metals in the muscle were many folds higher than the permissible level prescribed by some national and international legislation, which raises health risk concerns
l-Arginine Improves Sperm Motility in Threatened Coruh Trout Salmo coruhensis (Teleostei: Salmonidae)
No full textl-arginine is a versatile amino acid and precursor of nitric oxide that provides protection for preventing free radical damage. Herein, experiments were designed to clarify the effect of l-arginine supplementation on the sperm motility of a threatened trout, Coruh trout Salmo coruhensis. Activation solution was supplemented with levels of 0 mM (Control), 2 mM, 4 mM, and 8 mM l-arginine, and motility and survival of sperm cells were assessed. The selected concentrations were determined according to results of our preliminary experiments. The sperm motility rates at l-arginine concentrations of 0, 2, 4, and 8 mM were 73.33 ± 5.77%, 76.67 ± 5.75%, 80.01 ± 0.01%, and 90.00 ± 0.05%, respectively; notility durations were 21.67 ± 2.08, 32.33 ± 3.79, 32.67 ± 1.15, and 37.00 ± 6.38 s, respectively. Significant effect of l-arginine supplementation was determined on the percentage and duration of motile spermatozoa (p < 0.05). The maximum increment was evoked at the greatest concentration (8 mM). Here, we showed that l-arginine supplement can improve sperm motility of S. coruhensis
Web pages classification with parliamentary optimization algorithm
No full textIn recent years, data on the Internet has grown exponentially, attaining enormous dimensions. This situation makes it difficult to obtain useful information from such data. Web mining is the process of using data mining techniques such as association rules, classification, clustering, and statistics to discover and extract information from Web documents. Optimization algorithms play an important role in such techniques. In this work, the parliamentary optimization algorithm (POA), which is one of the latest social-based metaheuristic algorithms, has been adopted for Web page classification. Two different data sets (Course and Student) were selected for experimental evaluation, and HTML tags were used as features. The data sets were tested using different classification algorithms implemented in WEKA, and the results were compared with those of the POA. The POA was found to yield promising results compared to the other algorithms. This study is the first to propose the POA for effective Web page classification
Effect of Cobalt on Sperm Motility in an Endangered Trout Species, Salmo coruhensis
No full textExperiments were designed to examine the in vitro effect of cobalt on sperm motility of the endangered trout species (Salmo coruhensis). Sperm samples were diluted in an immobilizing solution, and activated in a motility-activation solution that was supplemented with cobalt at concentrations of 1, 10, 100 and 1000 mg/L. The percentage of motile sperm and duration of motility were determined. Cobalt concentrations of 1-100 mg/L had a positive effect on the percentage of motile sperm and duration of motility compared to the control group, while a concentration of 1000 mg/L resulted in decreases in these parameters (p < 0.05). The percentages of motile sperm at cobalt concentrations of 0, 1, 10, 100 and 1000 mg/L were 83.33% ± 0.25%, 88.33% ± 0.34%, 89.00% ± 0.57%, 90.00% ± 0.87% and 42.50% ± 0.45%, respectively; and the time durations over which the sperm remained motile were 72.00 ± 0.63, 74.83 ± 0.28, 77.40 ± 0.47, 81.14 ± 0.78, and 50.25 ± 0.67 s, respectively. This study has shown that sperm motility and duration were significantly enhanced (p < 0.05) at cobalt concentrations of 1, 10 and 100 mg/L, relative to controls, and significantly decreased at 1000 mg/L
Gundelia glabra miller (Compositae) - an ignored taxon
No full textWhen it was realized that Gundelia tournefortii L. (1753) consists of several clearly distinguishable taxa (Vitek et al. 2010) it was the next step to check all species and infra-specific taxa described later and treated as synonyms for their content
On complex -einstein normal complex contact metric manifolds
No full textThe aim of this paper is focusing on η-Einstein geometry of normal complex contact metric
manifolds. We give the definition of complex η-Einstein normal complex contact metric manifolds. In
addition, we study on concircular curvature tensor Z on a normal complex contact metric manifold
which satisfy Z(U, X)·Z = 0 and Z(V, X)·Z = 0. Also, we prove that a projectively semi-symmetric
normal complex contact metric manifold is complex η-Einstein
Regulation of signal transduction cascades by Pterostilbenes in different cancers: Is it a death knell for oncogenic pathways.
No full textInterdisciplinary research has revolutionized the field of medicine and we have witnessed exponential increase in the high-impact research in past few decades. However, the road to this burgeoning research field is obstacle-ridden because of intratumor heterogeneity, loss of apoptosis and dysregulation of spatio-temporally controlled signaling pathways. Ground-breaking findings obtained through genetic, genomic and proteomic studies have considerably improved our concepts related to the complexity of protein network and excitingly, discovery of miRNAs has added another layer of intricacy to quantitatively regulated gene networks. In this review, we chronicle the milestone achievements and discuss how Pterostilbenes effectively regulated different cellular pathways. We have provided detailed mechanistic insights related to regulation of JAK-STAT signaling, Notch pathway, Wnt mediated intracellular signaling by pterostilbene. Underlying mechanisms about regulation of PI3K/AKT and MAPK pathways by pterostilbene in different cancers. Regulation of Metastasis-associated protein 1 (MTA1) proteins and Human telomerase reverse transcriptase (hTERT) in cancer cells by pterostilbene. Pterostilbene has also been reported to modulate the expression of various oncogenic and tumor suppressor microRNAs in cancer cells. Better and sharper comprehension of the concepts associated with the modes of action of pterostilbene in different cancers will be useful in identification of cancers which can be efficiently targeted by pterostilbene
Determination of some Biological Properties over Kluyveromyces lactis 1 of Rheum ribes L. (Rhubarb) as a Traditional Medicinal and Food Plant.
No full textIn this study; fatty acid, vitamin, phytosterol, flavonoid and resveratrol contents and antimicrobial activities
of Rheum ribes L. (rhubarb) extracts treated with Kluyveromyces lactis 1 were determined and compared. R. ribes is known as both peptic and fibrous worldwide by humans. According to the results obtained; it was observed that total fatty acid, vitamin and phytosterol contents in R. ribes (rhubarb) extracts were at certain levels. It was detected that total fatty acid levels; at significant rates, vitamin contents; partly of R. ribes extracts prepared with K. lactis 1 increased; however, flavonoid contents decreased at different rates. In the study, it was noticed that R. ribes had antioxidant and antimicrobial activities at changing rates. When antimicrobial activities of R. ribes extracts containing K. lactis 1 were analyzed, it was observed that they had effect at changing rates against all of the bacteria, yeasts and dermatophyte fungi except Staphylococcus aureus of fatty acid extracts. On the other hand, vitamin and flavonoid extracts demonstrated scarcely any antimicrobial activity. In conclusion, it was detected that R. ribes, which has a local plant, had positive effects on the development of K. lactis 1 used in this study which is also accepted as a potential probiotic. It was observed that this yeast type developing in extracts obtained from plants affected biological active compounds at changing rates.FUBAP-190
Köprübaşı (Manisa) Uranyum Yatağının Çevresel Etkileri
No full textKÖPRÜBAŞI (MANİSA) URANYUM YATAĞININ ÇEVRESEL ETKİLERİ
Özlem Erdem
Jeoloji Mühendisliği Bölümü, Tunceli Üniversitesi, 62000, Tunceli, Türkiye, osenerdem@ tunceli.edu.tr
ÖZET
Köprübaşı (Manisa) uranyum yatağı, Türkiye’nin en önemli uranyum yataklarından birisidir ve Neojen yaşlı nehir çökelleri içerisinde yer alırlar. Yöredeki yataklar, mineralojik olarak oksitli ve oksitsiz cevher olmak üzere iki türde oluşmuştur. Oksitli yataklar ikincil jarosit-vaylandit ve manyetit-ilmenit, oksitsiz yataklar ise pirit ve siderit tipindedirler. Uranyumca zengin jarosit-vaylandit mineralleri, çökel kayaların epijenetik hamuru içinde kum ve çakıllar arasında bulunurlar. Yöredeki yataklar % 0.05-0.40 U3O8 tenörlü ve 2852 ton rezerve sahip olup, 1970’li yıllarda bir süre işletilmiş daha sonra terk edilmiştir. Bu çalışmada Köprübaşı uranyum yatağından kaynaklı toprak ve göl ve akarsu çökellerindeki başta U ve Th olmak üzere metal kirlenmesi ele alınmıştır.
Köprübaşı uranyum yatağı ve yakın çevresi, hem doğal, hem de yapılan madencilik çalışmalarından (antropojen) dolayı kirletilmiştir. Bu kirlenmeden, bölgedeki topraklar, yetişen bitkiler ve su kaynakları oldukça fazla etkilenmiştir. Köprübaşı uranyum yataklarının bulunduğu alanlar ve yakın çevresinden alınan çok sayıda toprak örneği, ICP-MS’de analiz edilmiş, uranyum da dahil olmak üzere toplam 53 elementin ppm ve ppb seviyesinde analizi yapılmıştır. Toprak örnekleri, üzerinde doğal olarak yetişen bitkilerin beslendiği kök sisteminin diplerine yakın yerlerden alınmıştır. Yöre topraklarının ortalama uranyum içeriği birkaç ppm’den 3876 ppm’e kadar değişmektedir. Gölsel çökellerin uranyum içeriği çok düşük olup, en fazla birkaç ppm’dir. Akarsu çökellerinin belli seviyelerinde ise uranyum içeriği çok yüksektir. Cevherleşmelerde uranyum, Bakır (0.94) ve Kurşun (0.81) ile kuvvetli pozitif, Arsen (0.19), Kadmiyum (0.20), Talyum (0.28) ve Selenyum (0.29) ile zayıf pozitif korelasyonlar gösterirken, Toryum ile herhangi bir korelasyon ilişkisi göstermemektedir
Optimization of process parameters for friction welding of SAE 1021/ Dillidur 400 / Dillimax 500 steels using taguchi technique
No full textBu çalışmanın amacı sürtünme kaynağı ile birleştirilen SAE 1021 karbonlu çelikler ile aşınma
direnci yüksek Dilludur 400 ve yüksek dayanıma sahip Dillimax 500 çeliklerin mekanik
özellikleri üzerine etki eden parametrelerin optimizasyonunu Taguchi analiz yöntemi ile
sağlamaktır. Taguchi analizi, yığma basıncı ve sürtünme devir hızı gibi kaynak parametreleri ile
birleştirilen malzeme türlerini optimize etmek için istatiksel deneysel tasarım olarak
kullanılmaktadır. Bu amaçla çelikler 1250, 1500 ve 1750 dev/dak sürtünme devirlerinde ve 4, 6
ve 8 MPa yığma basınçlarında birleştirilmiştir. Bağlantının mekanik özelliklerini belirlemek için
çekme testi ve mikro sertlik ölçümleri uygulanmıştır. Analiz sonuçlara göre malzeme çifti olarak
Dillidur 400-Dilimax 500, sürtünme devri olarak 1500 dev/dak ve yığma basıncının 6 MPa
seçilebileceği tespit edilmiştir. Ayrıca deneysel sonuçlara göre maksimum çekme dayanımı 651
MPa ile Dillidur 400- Dillidmax 500 çiftinde elde edilmiştir. Aynı malzeme çiftinde kaynak ara
yüzeyi sertlik değeri 353 HV’dir.The aim of this study is to optimize the welding parameters on the mechanical properties of SAE
1021 carbon steels and Dilldur 400 (high wear resistance) and Dillimax 500 (high strength) steels
joined with friction welding with Taguchi analysis method. Taguchi analysis is used as a
statistical experimental design to optimize material types joined with welding parameters such as
pressure of upsetting and friction rotational speed. For this purpose, the steels were joined at 1250,
1500 and 1750 rpm and at ups etting pressures of 4, 6 and 8 MPa. Tensile tests and microhardness
measurements were applied to determine the mechanical properties of the joint. According to the
results of analyse, it was determined that Dillidur 400-Dillimax 500 could be selected as material
pair. In addition, the friction speed and upsetting pressures can be selected 1500 rpm and 6 MPa
respectively. Also, according to the experimental results, maximum tensile strength was obtained
at the pair of Dillidur 400- Dillimax 500 with 651 MPa. In the same material pair, the welding
interface hardness value was 353 HV