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1

Effects of Thymol and Carvacrol on Acetylcholinesterase from Drosophila melanogaster

100%

Askin H., Yildiz M., Ayar A.

Acta Physica Polonica A

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2017

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vol. 132

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issue 3

720-722

EN

In this study, inhibitor effects of thymol and carvacrol were investigated in vivo and in vitro on acetylcholinesterase enzyme of Drosophila melanogaster. IC₅₀ values, Ki constants and inhibition types were determined for the substances displaying inhibitory effect. In vivo studies, were performed on larvaes by considering IC₅₀ values. The surviving and mortality rates were determined for the solution applied to larvaes. IC₅₀ values of thymol and carvacrol were found to be 25 mM and 0.175 mM, respectively. By using Lineweaver-Burk graphs, it was found that both compounds show non-competitive type of inhibition. According to results, it was concluded that carvacrol is a more effective inhibitor than thymol. We believe that these findings will contribute to the development of more potent, specific and effective inhibitors against AChE enzyme, design of new drugs for treating Alzheimer's disease and studies in pharmacological applications.

2

Connection Between Smoking Statuses and Anger-Anger Style of the Health Services Vocational School Students

100%

Say A., Ayar A., Çakir D.

Acta Physica Polonica A

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2017

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vol. 132

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issue 3

783-785

EN

This study was carried out at Sabuncuoğlu Şerefeddin Vocational School of Health Services, Amasya University. In this study, the relationship between smoking habits and rage and anger of the Vocational School students was examined for identification purposes. Within the scope of this study, the survey was performed to reach 608 out of 822 students in 2015-2016. The youth socioeconomic factors influencing smoking, cultural characteristics, as well as peer influence, emulation, school failure, loneliness, alcohol and drug use, social students' range and anger along with psychological factors, such as stress were analyzed cross-sectionally. The demographic questionnaire used for the data collection, information about smoking habits and the anger-anger scale were used. The independent variables were age, gender, type of school, parents' educational level, parental occupational status, income, and income perception. The reasons for smoking initiation, trying, quitting and continuing to smoke of smokers and non-smokers and anger styles related to these reasons were compared. Consequently, in our study, the smoking habits of males have been found more pronounced when compared to females. However, no significant relationship was found between the smoking habits and the anger-anger style. The age of smoking initiation has been determined to be proportional to the beginning of adolescence. This study will shed light on possibilities of smoking prevention and will facilitate quitting of smoking.

3

Influence of Laser Pulse Spatial Profile on Optodynamic Source Shape in Liquid Media

100%

Horvat D., Terzić M.

Acta Physica Polonica A

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2007

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vol. 112

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issue 5

1151-1156

EN

The aim of the present study is to demonstrate the influence of the spatial nonhomogeneity of the laser beam intensity profile on laser induced breakdown in aqueous medium with the use of optodynamic methods. In the experiment the optodynamic waves were induced with pulsed Nd:YAG laser beam which had several"hot spots". The resulting optodynamic transient waves were detected with two detectors: a laser beam deflection probe inside the liquid, parallel to the liquid surface and a piezoelectric transducer at the bottom of the container. The results of the experiment indicate the existence of numerous smaller waves that are observed before the main signal in the optodynamic wave form, contrary to wave forms generated with a laser beam having a smooth spatial profile.

4

Interaction Between Grapefruit Juice and Drugs

100%

Say A., Ayar A., Çakir D.

Acta Physica Polonica A

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2017

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vol. 132

|

issue 3

1030-1031

EN

Clinically significant grapefruit juice-drug interactions are an interesting development in the last ten years of research process in the scope of drug interactions. In 1989 a group of Canadian researchers found incidentally that grapefruit juice, used as a carrier system, interacts with some calcium channel blockers, while applying alcohol during a study on alcohol-drug interactions, and presented it in Lancet as a "short report". In this report it is stated that this effect of grapefruit juice is specific and there is no similar interaction with orange juice. The grapefruit juice interactions with drugs and changes in drug pharmacokinetics, individual responses to grapefruit juice in the relationship between the drug concentration and the effect began to gain a larger clinical significance. Drugs interacting with grapefruit juice are metabolized by cytochrome P450 enzyme system in liver or intestinal section. Flavonoids contained in grapefruit juice inhibit the enzyme, bind as a substrate to the enzyme system and disrupt its bioavailability. Naringin is an essential bioflavonoid in the grapefruit juice. Naringin is not a potent inhibitor of cytochrome P450, but it is partly metabolised to "Naringenin" by intestinal bacteria. This substance is a powerful inhibitor of cytochrome P450 and it is believed by some researchers, that these are components responsible for the effect of grapefruit juice. In 2008 the number of drugs that can cause danger when taken together with grapefruit was 17. It has been reported that this number has risen to 43 in 2012. However, while the research of the possible effects of other not yet identified components of the grapefruit juice is still in progress, FDA has begun to put cautionary statement to many drug prescriptions.

5

An Ellipsometrical and AFM Study οf Ferritin Adsorption Kinetics on a Gold Surface

51%

Vladimirova L., Andreeva A., Savov V., Gritzkow A., Burova M.

Acta Physica Polonica A

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2009

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vol. 116

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issue 4

687-689

EN

The kinetics of ferritin adsorption on gold (Au) surface was studied with ellipsometry and atomic force microscopy. The thickness and the refraction index of the adsorbed layer were determined using a theoretical model system: air-interface layer-solution-adsorbed layer-gold surface. The relations between the parameters of the adsorbed layer and pH and the protein concentration are obtained. It seems that the ferritin adsorption is a relatively slow multi-stage process. The obtained results enable modelling of the protein adsorption on blood vessels and tissues in pathological processes. The kinetics of protein adsorption could be implemented in medical applications and in development of new biosensor systems.

6

Measurement of Beet Root Extract Fluorescence Using TR-LIF Technique

51%

Rabasovic M., Sevic D., Terzic M., Savic-Sevic S., Muric B., Pantelic D., Marinkovic B.

Acta Physica Polonica A

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2009

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vol. 116

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issue 4

570-572

EN

Laser induced fluorescence is a powerful spectroscopic technique commonly used to study the structure and internal state distributions in molecules of biological interest. Betanin (C_{24}H_{26}N_{2}O_{13}) is a specific violet betacyanin and the most prominent pigment in the red beet root where it contributes to 75-95% of the total visible color. Our method of excitation of the beet root extract is based on the tunable (320 nm to 475 nm) Nd:YAG laser system. Fluorescence images of beet root extract excited at 320, 340, 360 and 400 nm were obtained. The fluorescence is observed in range from 580 nm to 660 nm. The influence of the solution concentrations on the fluorescence intensity is also analyzed.

7

Optically Pumped Mid-Infrared Stimulated Emission of ZnSe:Cr Crystals

51%

Ivanov V., Godlewski M., Szczerbakow A., Omel'chuk A., Davydov A., Zhavoronkov N., Raciukaitis G.

Acta Physica Polonica A

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2004

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vol. 105

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issue 6

553-558

EN

We demonstrate that ZnSe:Cr is an excellent solid state laser material for mid-infrared region with a broad amplification band from 2.2 μm to 3 μm, and with a high quantum efficiency of a radiative recombination. 46% external total efficiency and 56 mW threshold power were achieved, when pumped with a CW YAlO:Ho laser at resonant excitation conditions. Such laser system can have widespread applications in medicine as laser scalpels with regulated cutting depth. We further demonstrate a stimulated emission under Cr2+ to 1+ photo-ionization pumping. The latter opens chances for laser emission under carrier injection conditions.

8

Prediction of the Probabilities of the Transmission of Genetic Traits within Bayesian Logical Inference

38%

Cevri M., Üstündağ D.

Acta Physica Polonica A

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2016

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vol. 130

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issue 1

45-50

EN

Predictions for the transmission of genetic traits along to generations are an important process for patients, their family and genetic counseling. For this purpose, Bayesian analysis in which one can include a priori knowledge taking into account all relevant information into the problem could be a useful tool to examine how disease forecasting affects its probability so that it provides a more straightforward interpretation of predictions. Therefore, we investigate here transmissions of autosomal recessive diseases along to generations within Bayesian framework. In order to do that we develop a computer code that is useful to facilitate genetic transition matrices to forecast predictions of probabilities of transmission of genetic traits by using Mathematica software, well known as an algebraic manipulation language. Furthermore, the symbolic implementation of the code is applied for the cystic fibrosis disease forecasting in humans genetics. All results show that Bayesian analysis plays a central role of prediction for probabilities of transmissions of genetic traits along generations for cystic fibrosis disease or other autosomal recessive disorders.

9

Construction of Double Cladding Small Dispersion Photonic Crystal Fiber to Guide Ultrashort Pulse at 800~nm

38%

Stawska H., Bereś-Pawlik E.

Acta Physica Polonica A

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2012

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vol. 122

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issue 5

896-899

EN

The methods using femtosecond lasers are very popular in the world recently. They are used for different research methods. We begin to use a multi-photon autofluorescence method for cancer tissue detection. We plan to use this method with special photonic crystal fiber optic sensors. We would like to use to this detection femtosecond oscillator for 800 nm region. However, according to our information there is no fiber which can provide these femtosecond signals at 800 nm region without dispersion and nonlinear effect. Applying typical fiber causes dispersion of guided signals. Therefore we are preparing suitably designed fibers. Double-clad photonic fibers can play a dual role of ultrashort pulse delivery and efficient collection of nonlinear optical signals. In the paper a new design of double cladding small dispersion photonic crystal fiber is proposed. Simulations of both structure and dispersion in proposed fibers are presented.

Refine search results

Effects of Thymol and Carvacrol on Acetylcholinesterase from Drosophila melanogaster

Connection Between Smoking Statuses and Anger-Anger Style of the Health Services Vocational School Students

Influence of Laser Pulse Spatial Profile on Optodynamic Source Shape in Liquid Media

Interaction Between Grapefruit Juice and Drugs

An Ellipsometrical and AFM Study οf Ferritin Adsorption Kinetics on a Gold Surface

Measurement of Beet Root Extract Fluorescence Using TR-LIF Technique

Optically Pumped Mid-Infrared Stimulated Emission of ZnSe:Cr Crystals

Prediction of the Probabilities of the Transmission of Genetic Traits within Bayesian Logical Inference

Construction of Double Cladding Small Dispersion Photonic Crystal Fiber to Guide Ultrashort Pulse at 800~nm