Browsing by Author "Unal S."

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A data-driven approach to river discharge forecasting in the Himalayan region: Insights from Aglar and Paligaad rivers
(2024-06-01) Kumar V.; Unal S.; Bhagat S.K.; Tiyasha T.
Edge effects on gall-inducing insect Mikiola fagi (Diptera: Cecidomyiidae) in the oriental beach forests
(2015-01-01) Akkuzu E.; Dingiloʇlu E.; Unal S.
This study investigated the influence of forest edges on the leaf galls induced by Mikiola fagi (Hartig) on oriental beech (Fagus orientalis Lipsky). Two main objectives of this study were a) to compare the effects of forest edges on the number of leaf galls, and b) to compare the forest edges and forest interiors concerning the length and weight of the galls. Investigations on this subject were conducted in 2013-2014 in the Forest Enterprise Chief of Tezcan in Kastamonu located in Western Blacksea region of Turkey. The results showed that 1) the number of leaf galls was greater along the forest edges than in the forest interiors, 2) the length and the weight of the galls did not differ significantly between forest edges and forest interiors.
Investigation of antioxidant activities of Pleurotus ostreatus stored at different temperatures
(2018-06-01) Bakir T.; Karadeniz M.; Unal S.
In this study, the antioxidant capacity of oyster mushroom (Pleurotus ostreatus) stored in five different temperature environments was investigated by DPPH (1,1 diphenyl-2-picryl hydrazyl) radical scavenging method. The antioxidant capacity results of oyster mushroom extracts were examined by spectroscopic measurements and expressed as percent of inhibition. The IC50 values of mushroom samples were calculated with DPPH method using calibration equations, and change in antioxidant properties was also tried to decipher by SEM images. The IC50 values of Pleurotus ostreatus for four different concentrations were also found in h+20°C > inh+4°C> inh−10°C> inh−20°C> inh−40°C, respectively. As a conclusion, the temperature factor of oyster mushroom in the range of −40°C to +20°C storage conditions is directly proportional to the change of antioxidant properties. The results have shown the importance of logistics and storage conditions in preserving the antioxidant properties of oyster mushroom and similar food samples.
Ion implanted Au nanoparticles in surface plasmon temperature sensing
(2021-12-15) Unal S.
Temperature dependence of surface plasmon (SP) resonance from implanted Au nanoparticles have been studied in an ambient-air environment from 75 °C to 175 °C. Implantation provides encapsulated Au nanoparticles in a quartz substrate. The SP peak shifts linearly with the temperature increase. The experimental results were confirmed by the Drude model explaining the controlling mechanisms of the peak change. The Au nanoparticles have a higher volume thermal expansion coefficient than the substrate. Therefore, the dominant mechanism was the volume thermal expansion coefficient. This study provides another aspect of temperature sensing in Au nanoparticles which can be provided by ion implantation.
Ion implanted Au nanoparticles in surface plasmon temperature sensing
(2021-12-15) Unal S.; Unal, S
Temperature dependence of surface plasmon (SP) resonance from implanted Au nanoparticles have been studied in an ambient-air environment from 75 °C to 175 °C. Implantation provides encapsulated Au nanoparticles in a quartz substrate. The SP peak shifts linearly with the temperature increase. The experimental results were confirmed by the Drude model explaining the controlling mechanisms of the peak change. The Au nanoparticles have a higher volume thermal expansion coefficient than the substrate. Therefore, the dominant mechanism was the volume thermal expansion coefficient. This study provides another aspect of temperature sensing in Au nanoparticles which can be provided by ion implantation.
Larvaecidal effects of azadirachtin on the pine processionary moth
(2009-10-05) Unal S.; Akkuzu E.
The effects of azadirachtin, a natural extract of the neem tree Azadirachta indica A. Juss, on larval growth and feeding activity of pine processionary moth (Thaumetopoea pityocampa (Schiff.)) was investigated in laboratory experiments conducted in 2007 - 2008. The organic insecticide NeemAzal-T/S (a commercial neem preparation) was applied as suspension in distilled water at concentration levels of 0.3, 0.5 and 1%. Comparing with the untreated leaves, the effect of the insecticide NeemAzal-T/S was tested on the 10th day after treatment. The results obtained in conducted experiments indicated that NeemAzal-T/S was effective against T. pityocampa larvae, significantly inhibiting larval growth and reducing feeding activity. © 2009 Academic Journals.
Occurrence of Gregarina typographi (Apicomplexa, Gregarinidae) and Metschnikowia typographi (Ascomycota, Metschnikowiaceae) in Ips sexdentatus (Coleoptera: Curculionidae, Scolytinae) populations in Kastamonu (Turkey)
(2009-12-01) Unal S.; Yaman M.; Tosun O.; Aydin C.
In this study, Ips sexdentatus (Coleoptera: Curculionidae, Scolytinae) populations from Kastamonu (Turkey) were investigated for the occurrence of entomopathogens. Two species were encountered in the duration of this study and these were Gregarina typographi (Apicomplexa, Gregarinidae) and Metschnikowia typographi (Ascomycota, Metschnikowiaceae). Within the I. sexdentatus samples used in this study total infection rate of the pathogens G. typographi and M. typographi was calculated as 28.9%. Measurements of the Metschnikowia species identified from I. sexdentatus were, as follows: mean length 16.86±2.2 μm and mean width 2.8±0.3 μm (n = 125). The ascospores of this pathogen were characteristically needle-shaped and therefore, easily distinguishable under the light microscope. The occurrence rate for the ascomycete pathogen (M. typographi) was 3.1%. The gregarine pathogen measured 108.1-203.5 μm and was identified as Gregarina typographi. The occurrence rate for the Gregarine pathogen was 25.8%. The first report for Turkey (Kastamonu) of an ascomycete fungus, Meschnikowia typographi from the pine bark beetle Ips sexdentatus (Boerner) is given in this study. © Medwell Journals, 2009.
Predation efficacy of the predator Coccinella septempunctata L. on the Aphid species Macrosiphum rosae (L.) in Kastamonu Province, Turkey
(2017-01-01) Unal S.; Er A.; Akkuzu E.; Šálek L.
This study was conducted between the years 2013-2014 in order to determine the phenology of the predator Coccinella septempunctata Linnaeus (Coleoptera: Coccinellidae) and to evaluate its efficacy on Macrosiphum rosae (Linnaeus) (Hemiptera: Aphididae) in Kastamonu, Turkey. Rearing of C. septempunctata was carried out at 21.3±4.00°C and 78.8±9.44% relative humidity. The first, second, third and fourth larval instars of C. septempunctata consumed 20.3, 54.3, 108.2, and 232.7 M. rosea, respectively. The predation efficacy of the C. septempunctata was increased with the progress of the larval instars up to the fourth which was the most voracious.
SARS-CoV-2 Mutations and their Viral Variants
(2022-02-01) Cosar B.; Karagulleoglu Z.Y.; Unal S.; Ince A.T.; Uncuoglu D.B.; Tuncer G.; Kilinc B.R.; Ozkan Y.E.; Ozkoc H.C.; Demir I.N.; Eker A.; Karagoz F.; Simsek S.Y.; Yasar B.; Pala M.; Demir A.; Atak I.N.; Mendi A.H.; Bengi V.U.; Cengiz Seval G.; Gunes Altuntas E.; Kilic P.; Demir-Dora D.
Mutations in the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) occur spontaneously during replication. Thousands of mutations have accumulated and continue to since the emergence of the virus. As novel mutations continue appearing at the scene, naturally, new variants are increasingly observed. Since the first occurrence of the SARS-CoV-2 infection, a wide variety of drug compounds affecting the binding sites of the virus have begun to be studied. As the drug and vaccine trials are continuing, it is of utmost importance to take into consideration the SARS-CoV-2 mutations and their respective frequencies since these data could lead the way to multi-drug combinations. The lack of effective therapeutic and preventive strategies against human coronaviruses (hCoVs) necessitates research that is of interest to the clinical applications. The reason why the mutations in glycoprotein S lead to vaccine escape is related to the location of the mutation and the affinity of the protein. At the same time, it can be said that variations should occur in areas such as the receptor-binding domain (RBD), and vaccines and antiviral drugs should be formulated by targeting more than one viral protein. In this review, a literature survey in the scope of the increasing SARS-CoV-2 mutations and the viral variations is conducted. In the light of current knowledge, the various disguises of the mutant SARS-CoV-2 forms and their apparent differences from the original strain are examined as they could possibly aid in finding the most appropriate therapeutic approaches.
Wood-destroying Coleopteran species in the historical buildings in Kastamonu, in Turkey
(2009-05-18) Unal S.; Ozcan E.; Kaygin A.
The aim of this study is to identify the harmful insects causing damage in the historical wooden buildings of Kastamonu. Accordingly, 15 of those historical wooden buildings situated in the city were periodically controlled between the years 2002 and 2005. During those periodic controls, damages caused by insects were detected and additionally, dead and alive insects were collected from the damaged materials. As a result of this study, 7 species from 4 families were identified; these species are Anobium punctatum De Geer, Xestobium rufovillosum De Geer, Ernobius mollis (L.), Ptilinus pectinicornis (L.) (Anobiidae), Lyctus brunneus (Steph.) (Lyctidae), Hylotrupes bajulus (L.) (Cerambycidae) and Rhizopertha sp. (Bostriychidae). Except A. punctatum and H. bajulus, the rest are considered as the first records gathered in Kastamonu region. © 2009 Academic Journals.