Representations of an integer by some quaternary and octonary quadratic forms

In this paper we consider certain quaternary quadratic forms and octonary quadratic forms and by using the theory of modular forms, we find formulae for the number of representations of a positive integer by these quadratic forms.Comment: 20 pages, 4 tables. arXiv admin note: text overlap with arXiv:1607.0380

Mems Tabanlı Kuvvet Algılayıcıları İle Mikro Newton Mertebesinde Ölçüm

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2013Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2013Nanoteknolojideki gelişmeler sayesinde mikro ve nano seviyesindeki küçük ölçeklerde kuvvet üretimi ve üretilen kuvvetin ölçülmesi hem endüstrinin hem de akademinin ilgi alanına girmektedir. Bu çalışmada önerilen kuvvet ölçümü sistemi, yekpare olarak üretilmiş bir yay sistemi ve üçlü algılayıcı elektrot geometrisinden meydana gelmektedir. Bu elektrot kümelerinden ikisi sabit, birisi hareketli durumdadır. Dış bir kuvvetten uygulanan tahrik sonucunda oluşan yer değiştirme, hareketli elektrot kümesinin sabit kümelere göre yer değiştirmesine sebep olur. Bunun sonucunda sistemde oluşan sığa değişimi, sabit elektrot kümelerine uygulanan ve 1800 faz farkına sahip olan AC gerilimi neticesinde hareketli plakadan DC gerilimi olarak okunur. Bu çalışmada en fazla 30 N kuvveti okuyabilen bir kuvvet algılayıcı tasarımı gerçekleştirildi. Tasarım kriterlerini kontrol etmek amacıyla sonlu elemanlar yazılımı ile yöntem doğrulaması sağlandı. Bir sonraki adım olarak, tasarımı yapılan kuvvet algılayıcı, mikro-üretim yöntemleri kullanılarak imal edilecektir.With the continuous advances in the field of nanotechnology, both force generation and force measurement techniques at micro and nano scales are widely employed in industry and academia. The proposed force measurement system of this work consists of a monolithic flexural part and a sensor with the three-electrode geometry, namely “tri-plate geometry”, for capacitive displacement sensing. One of these sets of electrodes is movable, whereas the remaining two are fixed. Displacement of the movable set of electrodes induced by an external source results in a capacitive difference in between movable and fixed set of electrodes. This displacement is then sensed on the movable stack as a DC voltage output by applying an AC voltage of 1800 phase difference to the two fixed electrode sets. In this study, we propose a design of a force sensor which is able to detect a maximum force of 30 N. To verify the design, finite element simulations are carried out and shown to be in agreement with the design criteria. As a final step, fabrication of the force sensor will be carried out

Microcantilever based disposable viscosity sensor for serum and blood plasma measurements

This paper proposes a novel method for measuring blood plasma and serum viscosity with a microcantilever-based MEMS sensor. MEMS cantilevers are made of electroplated nickel and actuated remotely with magnetic field using an electro-coil. Real-time monitoring of cantilever resonant frequency is performed remotely using diffraction gratings fabricated at the tip of the dynamic cantilevers. Only few nanometer cantilever deflection is sufficient due to interferometric sensitivity of the readout. The resonant frequency of the cantilever is tracked with a phase lock loop (PLL) control circuit. The viscosities of liquid samples are obtained through the measurement of the cantilever's frequency change with respect to a reference measurement taken within a liquid of known viscosity. We performed measurements with glycerol solutions at different temperatures and validated the repeatability of the system by comparing with a reference commercial viscometer. Experimental results are compared with the theoretical predictions based on Sader's theory and agreed reasonably well. Afterwards viscosities of different Fetal Bovine Serum and Bovine Serum Albumin mixtures are measured both at 23. °C and 37. °C, body temperature. Finally the viscosities of human blood plasma samples taken from healthy donors are measured. The proposed method is capable of measuring viscosities from 0.86. cP to 3.02. cP, which covers human blood plasma viscosity range, with a resolution better than 0.04. cP. The sample volume requirement is less than 150. μl and can be reduced significantly with optimized cartridge design. Both the actuation and sensing are carried out remotely, which allows for disposable sensor cartridges. © 2013

Neurogenic bladder in patients with traumatic spinal cord injury: Treatment and follow-up

Study design:Multi-center, cross-sectional study.Objectives:Our aim was to evaluate the treatment methods and follow-up of neurogenic bladder in patients with traumatic spinal cord injury retrospectively using a questionnaire.Setting: Turkey.Methods:Three hundred and thirty-seven patients who had spinal cord injury for at least 2 years were enrolled from six centers in the neurogenic bladder study group. They were asked to fill-out a questionnaire about treatments they received and techniques they used for bladder management.Results:The study included 246 male and 91 female patients with a mean age of 42±14 years. Intermittent catheterization ( IC) was performed in 77.9% of the patients, 3.8% had indwelling catheters, 13.8% had normal spontaneous micturition, 2.6% performed voiding maneuvers, 1.3% used diapers and 0.6% used condom catheters. No gender difference was found regarding the techniques used in bladder rehabilitation ( P>0.05). Overall, 63.2% of patients used anticholinergic drugs; anticholinergic drug use was similar between genders ( P>0.05). The most common anticholinergic drug used was oxybutynin ( 40.3%), followed by trospium ( 32.6%), tolterodine ( 19.3%) darifenacin ( 3.3%), propiverine ( 3.3%) and solifenacin ( 1.1%). The specialties of the physicians who first prescribed the anticholinergic drug were physiatrists ( 76.2%), urologists ( 22.1%) and neurologists ( 1.7%). Only four patients had previously received injections of botulinum-toxin-A into the detrusor muscle and three of them stated that their symptoms showed improvement. Most of the patients ( 77%) had regular follow-up examinations, including urine cultures, urinary system ultrasound and urodynamic tests, when necessary; the reasons for not having regular control visits were living distant from hospital ( 15.3%) and monetary problems ( 7.7%). Of the patients, 42.7% did not experience urinary tract infections ( UTI), 36.4% had bacteriuria but no UTI episodes with fever, 15.9% had 1-2 clinical UTI episodes per year and 5% had ≥3 clinical UTIs. The clinical characteristics of patients with and without UTI ( at least one symptomatic UTI during 1 year) were similar ( P>0.05). The frequency of symptomatic UTI was similar in patients using different bladder management techniques ( P>0.05).Conclusion:The most frequently used technique for bladder rehabilitation in patients with SCI was IC ( 77.9%). In all, 63.2% of patients used anticholinergic drugs, oxybutynin being the most commonly used drug. Also, 77% of patients had regular control visits for neurogenic bladder; 42.7% did not experience any UTIs. © 2014 International Spinal Cord Society

Intermittent catheterization in patients with traumatic spinal cord injury: Obstacles, worries, level of satisfaction

Objectives: The aim of this study is to examine the obstacles in people with traumatic spinal cord injury (SCI) face performing intermittent catheterization (IC), also their worries and level of satisfaction. Methods: Two hundred sixty-nine patients performing IC for at least 3 months were asked to fill-out a questionnaire about their opinions on IC. Results: In total, 69.5% of patients performed IC themselves, 10.4% had performed by their mothers, 7.8% by another caregiver and 7.4% by their spouse. For the 72 (26%) patients unable to apply IC, reasons were insufficient hand function (56.1%), being unable to sit appropriately (35.4%) and spasticity (8.5%). In all, 70% of male patients had insufficient hand function, 20% could not sit and 10% had spasticity while 56.3% of female patients could not sit, 37.5% had insufficient hand function and 63% had spasticity. Difference between sexes was found to be statistically significant (P<0.05). Worries patients had when starting IC were fear of being dependent on IC (50.2%), accidentally injuring self (43.8%), embarrassment (43.2%), causing an infection (40.2%), bleeding (32.7%), fear of feeling pain (30.2%) and hygiene (24.7%). More women felt embarrassment; other items were similar in both sexes. In all, 46.9% of patients had urinary incontinence in intervals. Conclusion: In total, 69.5% of patients performed IC themselves. Men's most common obstacle was insufficient hand function while women's was being unable to sit appropriately. Patients' most common worries were being dependent on IC for life. In all, 46.9% had incontinence in intervals; 47.9% said IC improved their life quality; and 97.4% preferred IC over continuous catheterization. © 2014 International Spinal Cord Society All rights reserved

Examination of postgraduate theses on history textbooks in Turkey in terms of some variables

The purpose of this study was to examine the postgraduate theses that focused on history textbooks between 1989 and 2017 in Turkey. The population was composed of 126 postgraduate theses (master’s and doctoral) which were obtained from Thesis Center of Higher Education Council (HEC), Republic of Turkey. The document review method was used to evaluate the theses in the study. Thesis analysis form, which was developed by the researcher, was used as the data collection tool. This form involved items related to the theses’ levels, years, universities and institutes, title of the advisors, focus countries, and research design. The findings were interpreted making use of percentages and frequencies. The results showed that some universities in Turkey such as Gazi University distinguished themselves in terms of the number of theses on history textbooks. The fact that there were 108 master’s theses and 18 doctoral theses raises the importance of the current study. As a result of this study, discussion and some recommendations were presented about the theses on history textbooks. © 2018 Public Library of Science. All rights reserved

Lambert series and Liouville's identities

The relationship between Liouville's arithmetic identities and products of Lambert series is investigated. For example it is shown that Liouville's arithmetic formula for the sum where n ∈ N and F: Z → C is an even function, is equivalent to the Lambert series for given by Ramanujan