Electronic and Optical Properties of γ-Ag3SI by Using First Principles

Bahattin Erdinc,Harun Akkus 한국물리학회 2010 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.56 No.3

The electronic energy band structure and the optical properties of γ-Ag3SI are calculated by using density functional theory under the local density approximation (LDA). The calculated electronic band structure shows that γ-Ag3SI has an indirect gap with a value of 0.46 eV at the M →Γpoints in the Brillouin zone. A structural optimization has been performed by using the LDA. The optical spectra of the γ-Ag3SI in the photon range up to 30 eV are calculated by using a first-principles method under the scissor approximation. The real and the imaginary parts of the dielectric function as functions of the photon energy and, thus, the optical constants, such as the energy-loss function, the refractive index, and the effective number of electrons, are investigated. The calculated structural optimization of γ-Ag3SI is compared with the experimental results and is found to be in good agreement with the experimental data.

Strength of lap joints with embedded cover plate

Bahattin İşcan 대한기계학회 2015 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.29 No.5

In this study, stress behavior of double strap joints under tensile load has been investigated numerically and experimentally. In order tostrengthen the joint, the strap plates were embedded in the main adherend. In the tests, DP-810 was used as adhesive material while thesteel was employed as adherend. Experiments were conducted for various embedding heights, and lengths and overlap lengths. The impactsembedding height, length and total overlap length on tensile behavior have been investigated experimentally and numerically. Forconfirming the experimental results, numerical analyses were carried out with finite element method. It was concluded that numericalresults have good compatibility with experimental measurements. Increasing the height of the embedded cover plate resulted in decreasedstress values in adhesive layer. Besides, the increase in total overlap length caused an increase in stress values.

Some Characteristics and Isolation of Novel Thermostable β-Galactosidase from Thermus oshimai DSM 12092

Yüksel Gezgin,Bahattin Tanyolac,Rengin Eltem 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.1

The β-galactosidases belong to the class of hydrolytic enzymes and have been used as lactose hyrolysis. The enzyme is used in reducing lactose milk production, an outstanding industrial product used by a large lactoseintolerant population. This is the first detailed report of some characteristics of β-galactosidase and the gene encoding β-galactosidase in Thermus oshimai DSM 12092. The growth rate (μ, 1/h), and the doubling time (tD, h) for T. oshimai grown both in shaking flasks and in a bioreactor were determined. The optimal temperature and pH for β-galactosidase were determined as 75oC and 7.4, respectively. This enzyme was thermostable and was retained by more than 70% at 90oC for 3 h. The β-galactosidase from T. oshimai DSM 12092 was more stable in basic pH and Zn2+was the most effective divalent cation. Also, 2 steps of purification consisting of ammonium sulfate precipitation and gel filtration were employed and purified 32-fold.

Transumbilical scarless surgery with thoracic trocar

Ibrahim Uygun,Mehmet Hanifi Okur,Bahattin Aydogdu,Mehmet Serif Arslan,Hasan Cimen,,Selcuk Otcu 대한외과학회 2013 Annals of Surgical Treatment and Research(ASRT) Vol.84 No.6

Purpose: Single-site laparoscopic surgery has become increasingly common. We herein report an easy and low-cost thoracic trocar technique (TTT) for these types of procedures and recommend the simpler name “transumbilical scarless surgery” (TUSS) to minimize confusion in nomenclature. Methods: We retrospectively reviewed patients who underwent TUSS by TTT using a thoracic trocar and surgical glove in our hospital between November 2011 and November 2012. Operating time, postoperative stay, and complications were detailed. Results: A total of 101 TUSS by TTT were successfully performed, comprising appendectomy (n = 63), ovarian cyst excision (n = 7), splenectomy (n = 5), nephroureterectomy (n = 5), orchidopexy (n = 4), pyeloplasty (n = 3), nephrolithotomy (n = 2), orchiectomy (n = 2), varicocelectomy (n = 2), lymphangioma excision (n = 2), ureterectomy (n = 1), Morgagni diaphragmatic hernia repair (n = 1), ovarian detorsion (n = 1), antegrade continence enema (n = 1), intestinal resection anastomosis (n = 1), and intestinal duplication excision (n = 1). Kirschner wires were used for some organ traction. Nine patients required an additional port, but no major complications occurred. The postoperative stay (mean ± standard deviation) was 3.2 ± 1.4 days, and operating time was 58.9 ± 38.3 minutes. Conclusion: We recommend the simpler name of TUSS to minimize confusion in nomenclature for all transumbilical single-incision laparoendoscopic surgeries. TTT is an easy and low-cost TUSS technique.

Is platelet-rich plasma improves the anastomotic healing in hyperthermic intraperitoneal chemotherapy with oxaliplatin: an experimental rat study

Omer Faruk Buk,Sonmez Ocak,Bugra Genc,Bahattin Avcı,Hatice Olger Uzuner 대한외과학회 2020 Annals of Surgical Treatment and Research(ASRT) Vol.98 No.2

Purpose: Hyperthermic intraperitoneal chemotherapy (HIPEC) is a novel treatment option for peritoneal surface malignancies. Due to cytotoxic effects of chemotherapeutic agents, anastomosis healing can be impaired and lead to leakage rates higher than conventional intestinal surgery. In this experimental study, we aimed to investigate the effects of platelet-rich plasma (PRP) on colonic anastomosis in rats that received HIPEC with oxaliplatin. Methods: Thirty rats were divided into 3 groups. Group 1 was determined as control group and hyperthermic saline perfusion was performed after colon anastomosis. In group 2, colon anastomosis then hyperthermic oxaliplatin perfusion was performed. In the last group, the colonic anastomosis was enhanced by PRP gel and then hyperthermic oxaliplatin perfusion was performed. All the rats were reoperated on postoperative day 7 and anastomotic bursting pressure values were recorded. Tissue samples were taken for hydroxyproline assay and histopathological examination. Results: Control group had higher anastomotic bursting pressure value than group 2 and group 3 (P < 0.001). There were significant differences in anastomotic bursting pressure between groups 2 and 3 (P < 0.001). Group 2 had significantly lower hydroxyproline levels than group 3 and control group (P < 0.001). Histopathological examination revealed that PRP application reduced inflammatory response. Conclusion: PRP application on colonic anastomosis improves anastomotic healing and can reduce anastomosis related complications and stoma creation; though further clinical studies are needed.

An Incidentally Detected Breast Cancer on Tc-99m MIBI Cardiac Scintigraphy

Duray Seker,Gaye Seker,Emine Ozturk,Bahattin Bayar,Hakan Kulacoglu 한국유방암학회 2012 Journal of breast cancer Vol.15 No.2

Tc-99m methoxyisobutylisonitrile (MIBI) scintigraphy is generally used as a second-line diagnostic tool for obscured breast lesions. When the entire field of view is examined carefully, it is often possible to detect additional lesions unrelated to the initial intent and purpose of the examination. Herein we present a case of breast cancer incidentally detected by cardiac Tc-99m MIBI scintigraphy. An area of uptake was detected in the breast during a cardiac imaging test. Further evaluation of this lesion revealed a histopathological diagnosis of invasive ductal carcinoma of the breast. Sensitivity of this scintigraphic technique is not enough sufficient to use this test as a screening test for breast cancer, but it may provide supplemental information. Since it is not uncommon to find incidental lesions during imaging studies, examination of the image field may help clinicians find otherwise unrecognized or undiagnosed pathologies.

Cyclic and constacyclic self-dual codes over R_k

Suat Karadeniz,Ismail Gokhan Kelebek,Bahattin Yildiz 대한수학회 2017 대한수학회보 Vol.54 No.4

In this work, we consider constacyclic and cyclic self-dual codes over the rings $R_k$. We start with theoretical existence results for constacyclic and cyclic self-dual codes of any length over $R_k$ and then construct cyclic self-dual codes over $R_1 = \F_2+u\F_2$ of even lengths from lifts of binary cyclic self-dual codes. We classify all free cyclic self-dual codes over $R_1$ of even lengths for which non-trivial such codes exist. In particular we demonstrate that our constructions provide a counter example to a claim made by Batoul et al. in \cite{Batoul} and we explain why their claim fails.

CYCLIC AND CONSTACYCLIC SELF-DUAL CODES OVER R_k

Karadeniz, Suat,Kelebek, Ismail Gokhan,Yildiz, Bahattin Korean Mathematical Society 2017 대한수학회보 Vol.54 No.4

In this work, we consider constacyclic and cyclic self-dual codes over the rings $R_k$. We start with theoretical existence results for constacyclic and cyclic self-dual codes of any length over $R_k$ and then construct cyclic self-dual codes over $R_1={\mathbb{F}}_2+u{\mathbb{F}}_2$ of even lengths from lifts of binary cyclic self-dual codes. We classify all free cyclic self-dual codes over $R_1$ of even lengths for which non-trivial such codes exist. In particular we demonstrate that our constructions provide a counter example to a claim made by Batoul et al. in [1] and we explain why their claim fails.

Prognostic Factors in Oligodendrogliomas: a Clinical Study of Twenty-Five Consecutive Patients

Atalay, Tugay,Ak, Hakan,Celik, Bahattin,Gulsen, Ismail,Seckin, Hakan,Tanik, Nermin,Albayrak, Sedat Baki,Bavbek, Murad Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.13

Background: The purpose of this study was to evaluate the prognostic significance of Ki-67 and subjective microvascular density (SMVD) indexes together with other factors in patients with oligodendroglioma. Materials and Methods: In this retrospective study, oligodendroglioma specimens obtained from twenty-five consecutive patients were evaluated for Ki-67 and SMVD indices to help determine histological grading and investigate the fidelity of these markers in clinical prognosis. Other potentially prognostic factors were Karnofsky performance scale, tumor histological grade, and adjuvant radiotherapy. Results: The Ki-67 proliferation index appeared to have a strong correlation with the grade of the tumor and the survival. Age, gender, adjuvant radiotherapy, surgical resection type (complete versus incomplete) did not have any influence on recurrence. The SMVD index correlated significantly with the 3 to 5-year survival. Conclusions: Ki-67 and MVD indexes are important and useful markers in estimating the prognosis of oligodendrogliomas.

Evaluation of Platelet Indices in Lung Cancer Patients

Oncel, Mufide,Kiyici, Aysel,Oncel, Murat,Sunam, Guven Sadi,Sahin, Emel,Adam, Bahattin Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.17

Background: In this study, we aimed to determine platelet indices such as platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), Plateletcrit (PCT) platelet count (PLT) in lung cancer cases, and evaluate any relationships between these parameters and stage or histologic types. Materials and Methods: This retrospective study covered 44 lung cancer patients and 47 healthy subjects. Platelet indices including PLT, PCT, MPV, PDW were estimated and compared with normal subjects. The results were evaluated statistically. Results: The PDW value was significantly higher in the cancer group compared to the control group; however, the values for PCT and MPV were lower. Conclusions: We suggest potential use of platelet indices in diagnosis of lung cancer.