THE DIFFERENCE OF HYPERHARMONIC NUMBERS VIA GEOMETRIC AND ANALYTIC METHODS

Altuntas, Cagatay,Goral, Haydar,Sertbas, Doga Can Korean Mathematical Society 2022 대한수학회지 Vol.59 No.6

Our motivation in this note is to find equal hyperharmonic numbers of different orders. In particular, we deal with the integerness property of the difference of hyperharmonic numbers. Inspired by finiteness results from arithmetic geometry, we see that, under some extra assumption, there are only finitely many pairs of orders for two hyperharmonic numbers of fixed indices to have a certain rational difference. Moreover, using analytic techniques, we get that almost all differences are not integers. On the contrary, we also obtain that there are infinitely many order values where the corresponding differences are integers.

Effect of Packaging Methods on Colour, Lipid Quality and Microbial Growth of Beef Patties Enhanced with Flaxseed Flour

Altuntas, Irem,Turhan, Sadettin Korean Society for Food Science of Animal Resource 2013 한국축산식품학회지 Vol.33 No.1

In this study, the effect of packaging methods [aerobic packaging (AP), vacuum packaging (VP) and modified atmosphere packaging (MAP: 75% $N_2$, 25% $CO_2$)] on colour, lipid quality and microbial growth of beef patties enhanced with flaxseed flour was investigated during storage at $2{\pm}1^{\circ}C$ for 10 d. L and a values of beef patties packaged in MAP and VP were higher (p<0.05) than that of the samples packaged in AP. Packaging in MAP and VP retarded the lipid oxidation (TBA value) and inhibited the bacterial growth of beef patties enhanced with flaxseed flour. Furthermore, TBA values in beef patties were correlated with a values (r = -0.340; p<0.05). Packaging in MAP was more effective than packaging in VP for inhibiting microbial growth. The samples packaged in VP lost their shape due to the compression by external atmosphere. Packaging treatment had no significant effect on saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) levels in beef patties. The a and b, TBA and MUFA values changed during storage time. TBA values for beef patties increased during storage time, but did not reach to the limit value (1 mg/kg) until the end of the storage time. The results suggest that the shelf life of beef patties enhanced with flaxseed flour can be extended by packaging in MAP.

Isolated Congenital Nasal Bifid Septum Separated by a Wide Layer of Soft Tissue

Karacor-Altuntas, Zeynep,Dundar, Mehmet Akif,Dadaci, Mehmet,Ince, Bilsev Korean Society of Plastic and Reconstructive Surge 2015 Archives of Plastic Surgery Vol.42 No.5

A Comparative Study on Electrical Characteristics of Crystalline AlN Thin Films Deposited by ICP and HCPA-Sourced Atomic Layer Deposition

Halit Altuntas,Turkan Bayrak 대한금속·재료학회 2017 ELECTRONIC MATERIALS LETTERS Vol.13 No.2

In this work, we aimed to investigate the effects of two different plasma sourceson the electrical properties of low-temperature plasma-assisted atomic layerdeposited (PA-ALD) AlN thin films. To compare the electrical properties,50 nm thick AlN films were grown on p-type Si substrates at 200 °C by usingan inductively coupled RF-plasma (ICP) and a stainless steel hollowcathode plasma-assisted (HCPA) ALD systems. Al/AlN/p-Si metal-insulatorsemiconductor(MIS) capacitor devices were fabricated and capacitance versusvoltage (C-V) and current-voltage (I-V) measurements performed to assess thebasic important electrical parameters such as dielectric constant, effectivecharge density, flat-band voltage, breakdown field, and threshold voltage. Inaddition, structural properties of the films were presented and compared. Theresults show that although HCPA-ALD deposited AlN thin films hasstructurally better and has a lower effective charge density (Neff) value thanICP-ALD deposited AlN films, those films have large leakage current, lowdielectric constant, and low breakdown field. This situation was attributed tothe involvement of Si atoms into the AlN layers during the HCPA-ALDprocessing leads to additional current path at AlN/Si interface and might impairthe electrical properties. PACS: 73.30.+y: 73.40.Qv: 73.40.Ns

Effect of Pyrene-1 Boronic Acid Functionalization on the Electrical Characteristics of Carbon Nanotube Field-Effect Transistor

H. Altuntas,K. Snashall,F. Oke-Altuntas,I. Jayawerdane,M. O. Tas,S. Ravi P. Silva 대한금속·재료학회 2023 ELECTRONIC MATERIALS LETTERS Vol.19 No.5

Carbon nanotube fi eld-eff ect transistor (CNT-FET) based sensor devices are widely used in sensing applications of biomolecules in high sensitivity. In addition, covalent functionalization process can increase the interaction between the CNTs and biological molecules. In this article, we present the eff ect of boronic acid functionalization on the electrical properties of the CNT-FET due to boronic acid and its derivatives have been widely used for the glucose recognition. For this purpose, CNT-FET transistors were fabricated on SiO 2 /Si substrates utilising high purity semiconducting nanotubes as the channel layer and functionalized with pyrene-1-boronic acid. It was found that boronic acid functionalization causes a variation in electrical parameters of CNT-FET transistors such as conductance, transconductance, threshold voltage, fi eld eff ect mobility, resistance, hysteresis gap, and charge transfer of carriers per unit length. The results show that pyrene-1- boronic acid treatment was observed to have a signifi cant benefi cial eff ect on the electrical properties of the CNT-FET and pyrene-1-boronic acid functionalized CNT-FET sensor devices may have great potential for glucose sensing applications.

ON THE p-ADIC VALUATION OF GENERALIZED HARMONIC NUMBERS

Cagatay Altuntas 대한수학회 2023 대한수학회보 Vol.60 No.4

For any prime number $p$, let $J(p)$ be the set of positive integers $n$ such that the numerator of the $n^{th}$ harmonic number in the lowest terms is divisible by this prime number $p$. We consider an extension of this set to the generalized harmonic numbers, which are a natural extension of the harmonic numbers. Then, we present an upper bound for the number of elements in this set. Moreover, we state an explicit condition to show the finiteness of our set, together with relations to Bernoulli and Euler numbers.

Effect of Packaging Methods on Colour, Lipid Quality and Microbial Growth of Beef Patties Enhanced with Flaxseed Flour

Irem Altuntas,Sadettin Turhan 한국축산식품학회 2013 한국축산식품학회지 Vol.33 No.1

In this study, the effect of packaging methods [aerobic packaging (AP), vacuum packaging (VP) and modified atmosphere packaging (MAP: 75% N2, 25% CO2)] on colour, lipid quality and microbial growth of beef patties enhanced with flaxseed flour was investigated during storage at 2±1ºC for 10 d. L and a values of beef patties packaged in MAP and VP were higher (p<0.05) than that of the samples packaged in AP. Packaging in MAP and VP retarded the lipid oxidation (TBA value) and inhibited the bacterial growth of beef patties enhanced with flaxseed flour. Furthermore, TBA values in beef patties were correlated with a values (r = -0.340; p<0.05). Packaging in MAP was more effective than packaging in VP for inhibiting microbial growth. The samples packaged in VP lost their shape due to the compression by external atmosphere. Packaging treatment had no significant effect on saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) levels in beef patties. The a and b, TBA and MUFA values changed during storage time. TBA values for beef patties increased during storage time, but did not reach to the limit value (1 mg/kg) until the end of the storage time. The results suggest that the shelf life of beef patties enhanced with flaxseed flour can be extended by packaging in MAP.

Use of a Temporary Shunt as a Salvage Technique for Distal Extremity Amputations Requiring Repair by Vessel Grafting during Critical Ischemia

Ince, Bilsev,Dadaci, Mehmet,Altuntas, Zeynep Korean Society of Plastic and Reconstructive Surge 2016 Archives of Plastic Surgery Vol.43 No.6

Background Although the use of temporary shunts in proximal extremity amputations has been reported, no study has described the use of temporary shunts in distal extremity amputations that require vein grafting. Moreover, the total volume of blood loss when temporary shunts are used has not been reported. The aim of this study was to investigate the applicability of a temporary shunt for distal extremity amputations requiring repair by vessel grafting with an ischemia time of >6 hours. This study also aimed to determine the total volume of blood loss when temporary shunts were used. Methods Patients who underwent distal major extremity replantation and/or revascularization with a vessel graft and who experienced ischemia for 6-8 hours between 2013 and 2014 were included in the study. A 6-Fr suction catheter was cut to 5 cm in length after the infusion of heparin, and secured with a 5-0 silk suture between the distal and the proximal ends of the artery. While bleeding continued, the bones were shortened and fixed. After the complete restoration of circulation, the arterial shunt created using the catheter was also repaired with a vein graft. Results Six patients were included in this study. The mean duration of ischemia was 7.25 hours. The mean duration of suction catheter use during limb revascularization was 7 minutes. The mean transfusion volume was 7.5 units. No losses of the extremity were observed. Conclusions This procedure should be considered in distal extremity amputations requiring repair by vessel grafting during critical ischemia.

Acute Lymphoblastic Leukemia Associated with Brucellosis in Two Patients with Fever and Pancytopenia

Bulent Eser,Fevzi Altuntas,Isin Soyuer,Ozlem Er,Ozlem Canoz,Hasan Senol Coskun,Mustafa Cetin,Ali Unal 연세대학교의과대학 2006 Yonsei medical journal Vol.47 No.5

Brucellosis is a disease involving the lymphoproliferative system, which may lead to changes in the hematological parameters; however, pancytopenia is a rare finding. However, malignant diseases in association with brucellosis are rarely the cause of pancytopenia. Herein, two cases with fever and pancytopenia, diagnosed as simultaneous acute lymphoblastic leukemia and brucellosis are presented. Anti-leukemic therapy and brucellosis treatment were administered simultaneously, and normal blood parameters obtained. The first patient is in complete remission; the other recovered from the brucellosis, but later died due to a leukemic relapse.

Importance of Postoperative Stimulated Thyroglobulin Level at the Time of ¹³¹I Ablation Therapy for Differentiated Thyroid Cancer

Hasbek, Zekiye,Turgut, Bulent,Kilicli, Fatih,Altuntas, Emine Elif,Yucel, Birsen Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.6

Background: Serum thyroglobulin detection plays an essential role during the follow-up of thyroid cancer patients treated with total/near total thyroidectomy and radioiodine ablation. The aim of this retrospective study was to evaluate the relationship between stimulated serum thyroglobulin (Tg) level at the time of high dose $^{131}I$ ablation and risk of recurrence, using a three-level classification in patients with differentiated thyroid cancer (DTC) according to the ATA guidelines. Also we investigated the relationship between postoperative stimulated Tg at the time of ablation and DxWBS results at 8-10 months thereafter. Materials and Methods: Patients with radioiodine accumulation were regarded as scan positive (scan+). If there was no relevant pathological radioiodine accumulation or minimal local accumulation in the thyroid bed region, this were regarded as scan negative (scan-) at the time of DxWBS. We classified patients in 3 groups as low, intermediate and high risk group for assessment of risk of recurrence according to the revised ATA guidelines. Also, we divided patients into 3 groups based on the stimulated serum Tg levels at the time of $^{131}I$ ablation therapy. Groups 1-3 consisted of patients who had Tg levels of ${\leq}2ng/ml$, 2-10 ng/ml, and ${\geq}10ng/ml$, respectively. Results: A total of 221 consecutive patients were included. In the high risk group according to the ATA guideline, while 45.5% of demonstrated Scan(+) Tg(+), 27.3% of patients demonstrated Scan(-) Tg(-); in the intermediate group, the figures were 2.3% and 90.0% while in the low risk group, they were 0.6% and 96.4%. In 9 of 11 patients with metastases (81.8%), stimulated serum Tg level at the time of radioiodine ablation therapy was over 10, however in 1 patient (9.1%) it was <2ng/mL and in one patient it was 2-10ng/mL (p=0.005). Aggressive subtypes of DTC were found in 8 of 221 patients and serum Tg levels were ${\leq}2ng/ml$ in 4 of these 8. Conclusions: We conclude that TSH-stimulated serum thyroglobulin level at the time of ablation may not determine risk of recurrence. Therefore, DxWBS should be performed at 8-12 months after ablation therapy.