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Publication Metadata only 1200 nm pumped Tm3+:Lu2O3 ceramic lasers(Optical Soc Amer, 2018) Özharar, Sarper; N/A; Department of Physics; Toker, Işınsu Baylam; Sennaroğlu, Alphan; PhD Student; Faculty Member; Department of Physics; N/A; College of Sciences; N/A; 23851We report on an experimental demonstration of a 1200-nm pumped Tm3+:Lu2O3 ceramic laser. By using a gain-switched, tunable Cr4+:forsterite laser, the excitation spectrum was measured, with optimum pumping bands centered near 1198 nm, 1204 nm, and 1211 nm. The highest slope efficiency of 21.5% was obtained at the pump wavelength of 1204 nm. Comparative energy efficiency measurements performed near 1200-nm and 800-nm pumping further showed that nearly 40% improvement was obtained in slope efficiency measured with respect to the incident pump energy for 1200-nm pumping. A transition was further observed from single-wavelength operation at 2066 nm to dual-wavelength operation near 2066 nm and 1967 nm for absorbed pump energies above 50 mu J. In this regime, two consecutive output pulses were observed in the time domain. The shortest temporal duration of the first pulse was 1.1 mu s at the incident pulse energy of 105 mu J. The duration and build-up time of the second pulse remained around 5.9 mu s and 18.5 mu s. We believe that the improved energy efficiency demonstrated for the 1.5% Tm3+:Lu2O3 ceramic with 1200-nm pumping can be used as an alternative scheme for the excitation of Tm3+:Lu2O3 ceramic lasers.Publication Metadata only A biallelic ANTXR1 variant expands the anthrax toxin receptor associated phenotype to tooth agenesis(Wiley, 2018) Dinckan, Nuriye; Du, Renqian; Akdemir, Zeynep C.; Bayram, Yavuz; Jhangiani, Shalini N.; Doddapaneni, Harsha; Hu, Jianhong; Muzny, Donna M.; Guven, Yeliz; Aktoren, Oya; Boerwinkle, Eric; Gibbs, Richard A.; Posey, Jennifer E.; Lupski, James R.; Uyguner, Zehra O.; Letra, Ariadne; N/A; Kayserili, Hülya; Faculty Member; School of Medicine; 7945Tooth development is regulated by multiple genetic pathways, which ultimately drive the complex interactions between the oral epithelium and mesenchyme. Disruptions at any time point during this process may lead to failure of tooth development, also known as tooth agenesis (TA). TA is a common craniofacial abnormality in humans and represents the failure to develop one or more permanent teeth. Many genes and potentially subtle variants in these genes contribute to the TA phenotype. We report the clinical and genetic impact of a rare homozygous ANTXR1 variant (c.1312C>T), identified by whole exome sequencing (WES), in a consanguineous Turkish family with TA. Mutations in ANTXR1 have been associated with GAPO (growth retardation, alopecia, pseudoanodontia, and optic atrophy) syndrome and infantile hemangioma, however no clinical characteristics associated with these conditions were observed in our study family. We detected the expression of Antxr1 in oral and dental tissues of developing mouse embryos, further supporting a role for this gene in tooth development. Our findings implicate ANTXR1 as a candidate gene for isolated TA, suggest the involvement of specific hypomorphic alleles, and expand the previously known ANTXR1-associated phenotypes.Publication Open Access A case of Burkitt’s lymphoma mimicking peritonitis carcinomatosa(Galenos Yayınevi, 2020) Örnek, Serdar; Tecimer Tülay; Ferhanoğlu, Ahmet Burhan; Büyüktaş, Deram; Faculty Member; Faculty Member; School of Medicine; 18320; N/APublication Metadata only A case of drop foot due to piriformis syndrome(Springer Heidelberg, 2015) Yıldırım, Pelin; Güler, Tuba; Özer, Tülay; Gündüz, Osman Hakan; N/A; Mısırlıoğlu, Tuğçe Özekli; Doctor; N/A; Koç University Hospital; 175999N/APublication Metadata only A case of secondary hemophagocytic lymphohistiocytosis (HLH) following incomplete kawasaki's disease (KD). Importance of distinguishing recurrent kd from HLH(2014) Kebudi, R.; Dindar, A.; Gürakan, F.; Devecioğlu, O.; Sözmen, Banu Oflaz; Faculty Member; School of Medicine; 198711N/APublication Open Access A characterization of the extended serial correspondence(Elsevier, 2015) Heo, Eun Jeong; Department of Economics; Yılmaz, Özgür; Faculty Member; Department of Economics; College of Administrative Sciences and Economics; 108638We study the problem of assigning objects to a group of agents. We focus on probabilistic methods that take agents' ordinal preferences over the objects. Importantly, we allow for indifferences among objects. Katta and Sethuraman (2006) propose the extended serial correspondence to solve this problem. Our main result is a characterization of the extended serial correspondence in welfare terms by means of stochastic dominance efficiency, stochastic dominance no-envy and "limited invariance," a requirement we adapt from Heo (2014a). We also prove that an assignment matrix is selected by the extended serial correspondence if and only if it satisfies "non-wastefulness" and "ordinal fairness," which we adapt from Kesten et al.Publication Open Access A clinical comparison of home-based and hospital-based exercise programs following arthroscopic capsulolabral repair for anterior shoulder instability(Human Kinetics, 2020) Atalar, Ata Can; Eren, Şule Meral; Uçak, Ayla; Çerezci, Önder; Eren, İlker; Canbulat, Nazan; Demirhan, Mehmet; Faculty Member; Faculty Member; School of Medicine; Koç University Hospital; 168021; 58534; 9882Context: ideal rehabilitation method following arthroscopic capsulolabral repair surgery for anterior shoulder instability has not been proven yet. Although rapid or slow protocols were compared previously, home- or hospital-based protocols were not questioned before. Objective: the aim of this prospective unrandomized controlled clinical trial is to compare the clinical outcomes of home-based and hospital-based rehabilitation programs following arthroscopic Bankart repair. Design: non-randomized controlled trial. Setting: orthopedics and physical therapy units of a single institution. Patients: fifty-four patients (49 males and 5 females) with an average age of 30.5 (9.1) years, who underwent arthroscopic capsulolabral repair and met the inclusion criteria, with at least 1-year follow-up were allocated into 2 groups: home-based (n = 33) and hospital-based (n = 21) groups. Interventions: both groups received identical rehabilitation programs. Patients in the home-based group were called for follow-up every 3 weeks. Patients in the hospital-based group admitted for therapy every other day for a total of 6 to 8 weeks. Both groups were followed identically after the eighth week and the rehabilitation program continued for 6 months. Main Outcome Measures: Clinical outcomes were assessed using Disabilities of Arm Shoulder Hand, Constant, and Rowe scores. Mann-Whitney U test was used to compare the results in both groups. Wilcoxon test was used for determining the progress in each group. Results: groups were age and gender matched (P =.61, P =.69). Average number of treatment sessions was 13.8 (7.3) for patients in the hospital-based group. Preoperative Disabilities of Arm Shoulder Hand (27.46 [11.81] vs 32.53 [16.42], P =.22), Constant (58.23 [14.23] vs 54.17 [10.46], P =.13), and Rowe (51.72 [15.36] vs 43.81 [19.16], P =.12) scores were similar between groups. Postoperative scores at sixth month were significantly improved in each group (P =.001, P =.001, and P =.001). No significant difference was observed between 2 groups regarding clinical scores in any time point. Conclusions: we have, therefore, concluded that a controlled home-based exercise program is as effective as hospital-based rehabilitation following arthroscopic capsulolabral repair for anterior shoulder instability.Publication Open Access A clinical scoring system to predict the development of bronchopulmonary dysplasia(Thieme Medical Publishers, 2015) Hayran, Mutlu; Derin, Hatice; Ovalı, Fahri; N/A; Gürsoy, Tuğba; Faculty Member; School of Medicine; 214691Objective: This study aims to develop a scoring system for the prediction of bronchopulmonary dysplasia (BPD). Methods: Medical records of 652 infants whose gestational age and birth weight were below 32 weeks and 1,500g, respectively, and who survived beyond 28th postnatal day were reviewed retrospectively. Logistic regression methods were used to determine the clinical and demographic risk factors within the first 72 hours of life associated with BPD, as well as the weights of these factors on developing BPD. Predictive accuracy of the scoring system was tested prospectively at the same unit. ResultsBirth weight, gestational age, gender, presence of respiratory distress syndrome, patent ductus arteriosus, intraventricular hemorrhage, hypotension were the most important risk factors for BPD. Therefore, a scoring system (BPD-TM score) ranging from 0 to 13 and grouped in four tiers (0-3: low, 4-6: low intermediate, 7-9: high intermediate, and 10-13: high risk) was developed based on these factors. Below the score of 4, 4.1% of infants (18/436), above the score of 9, 100% (29/29) of the infants developed BPD. The score was validated successfully in 172 infants. Conclusion: With this easy to use scoring system, one can predict the neonate at risk for BPD at 72 hours of life and direct preventive measures toward these infants.Publication Metadata only A coarse grained simulation study on the morphology of aba triblock copolymers(Elsevier, 2019) Onarana, Gülşah; Yurtsever, Mine; Department of Chemistry; Yılgör, İskender; Faculty Member; Department of Chemistry; College of Sciences; 24181The Dissipative Particle Dynamics (DPD) simulation technique was used to elucidate the composition-dependent equilibrium morphological behavior of three different symmetric ABA triblock copolymers, which were; poly(epsilon-caprolactone)-poly(dimethylsiloxane)-poly(epsilon-caprolactone) (PCL-PDMS-PCL), poly(epsilon-caprolactone)-poly(ethylene oxide)-poly(epsilon-caprolactone) (PCL-PEO-PCL) and poly(L-lactide)-poly(dimethylsiloxane)-poly(L-lactide) (PLLA-PDMS-PLLA). These polymers were chosen due to their biomedical and biotechnological importance. Polymeric A and B blocks were modeled as connected chain of beads with varying incompatibility. The impact of the block incompatibilities on the microphase separation as well as on the equilibrium phase behaviors were investigated at the mesoscopic scale. A detailed visual analysis of the DPD images and constructed phase diagram showed that quite different equilibrium morphologies were attainable by controlling the molecular weights of the blocks and the strength of the intermolecular interaction between them. More compatible A and B blocks underwent lamellar to cylindrical and cylindrical to spherical phase transitions at lower B block concentrations. Our results clearly showed that, Flory-Huggins interaction parameter (chi) and degree of polymerization (N) were the only control parameters, which determined the shape and size of the phase domains, as well as the extent of equilibrium nanophase separation. Our DPD simulated morphologies were compared with experimental images obtained by Atomic Force Microscopy (AFM).Publication Metadata only A combined clinical and computational approach to understand the SOD1(A4T)-mediated pathogenesis of rapidly progressive familial amyotrophic lateral sclerosis(Springer Heidelberg, 2022) Diker, Sevda; Gelener, Pınar; Teralı, Kerem; Ergören, Mahmut Çerkez; Ersin, Tan; N/A; N/A; Tunca, Ceren; Başak, Ayşe Nazlı; Researcher; Faculty Member; Koç University Research Center for Translational Medicine (KUTTAM) / Koç Üniversitesi Translasyonel Tıp Araştırma Merkezi (KUTTAM); N/A; School of Medicine; N/A; 1512Here, we aim to provide a comprehensive clinical and biomolecular description of familial amyotrophic lateral sclerosis (fALS) in a 25-year-old female patient with respect to the SOD1(A4T) genotype. The clinical diagnosis of the disease was based on family history, neurological examination, electroneurophysiological studies, and revised El Escorial criteria. The heterozygous presence of the A4T mutation in the proband was confirmed by PCR coupled with Sanger sequencing of exon 1 of the SOD1 gene. The mutation was introduced in silico into the three-dimensional structure of the native protein. After energy minimization and quality assessment, non-covalent interactions around threonine-4 and changes in protein stability were calculated computationally. The patient differed widely in age at onset, initial neurological symptoms and findings, and survival time from her kindred, in which several members are affected. SOD1(A4T)-linked fALS in this case had bulbar involvement at onset, a combination of lower and upper motor neuron signs and showed rapid progression. Unlike alanine-4, threonine-4 failed to engage in hydrophobic interactions with the vicinal non-polar amino acids. The overall fold of the modeled SOD1(A4T) mutant remained intact, but unfolding free energy estimations disclosed a decrease in the protein's stability. We report a phenotypically distinct patient with fALS due to the SOD1(A4T) mutation and further expand the largest pedigree ever published for SOD1(A4T)-linked fALS. Genotype-phenotype correlation in fALS is complex, and it demands detailed clinical investigation and advanced scientific research. Awareness of the broadened phenotypic spectrum might potentially enhance the diagnosis and genetic counseling of fALS.Publication Open Access A combined VBM and DTI study of schizophrenia: bilateral decreased insula volume and cerebral white matter disintegrity corresponding to subinsular white matter projections unlinked to clinical symptomatology(Aves, 2017) Ulaşoğlu-Yıldız, Çiğdem; Aslan, Selçuk; Talı, Erhan Turgut; N/A; N/A; Onay, Aslıhan; Eser, Hale Yapıcı; Faculty Member; School of Medicine; N/A; 134359PURPOSE: Grey matter and white matter changes within the brain are well defined in schizophrenia. However, most studies focused on either grey matter changes or white matter integrity separately; only in limited number of studies these changes were interpreted in the same frame. In addition, the relationship of these findings with clinical variables is not clearly established. Here, we aimed to investigate the grey matter and white matter changes in schizophrenia patients and exhibit the relation of these imaging findings with clinical variables. METHODS: A total of 20 schizophrenia patients and 16 matched healthy controls underwent magnetic resonance imaging to investigate the grey matter and white matter alterations that occur in schizophrenia patients using voxel-based morphometry (VBM) and whole brain voxel-wise analysis of diffusion tensor imaging (DTI) parameters with SPM8, respectively. While the preprocessing steps ofVBM were performed with the default parameters of VBM8 toolbox, the preprocessing steps of DTI were carried out using FSL. Additionally, VBM results were correlated with clinical variables. RESULTS: Bilateral insula showed decreased grey matter volume in schizophrenia patients compared with healthy controls (P < 0.01). The opposite contrast did not show a significant difference. Psychiatric scores, duration of illness, and age were not correlated with the decreased grey matter volume of insula in schizophrenia patients. DTI analysis revealed a significant increase in mean, radial, and axial diffusivity, mainly of the fibers of bilateral anterior thalamic radiation and superior longitudinal fasciculus with left predominance, which intersected with bilateral subinsular white matter (P < 0.05). CONCLUSION: Our findings suggest that insula may be the main affected brain region in schizophrenia, which is also well supported by the literature. Our results were independent of disease duration and schizophrenia symptoms. White matter alterations were observed within bilateral anterior thalamic radiation and superior longitudinal fasciculus that intersects with subinsular white matter. Studies with larger sample sizes and more detailed clinical assessments are required to understand the function of insula in the neurobiology of schizophrenia.Publication Metadata only A communication theoretical modeling of axonal propagation in hippocampal pyramidal neurons(IEEE-Inst Electrical Electronics Engineers Inc, 2017) N/A; N/A; Department of Electrical and Electronics Engineering; Ramezani, Hamideh; Akan, Özgür Barış; PhD Student; Faculty Member; Department of Electrical and Electronics Engineering; Graduate School of Sciences and Engineering; College of Engineering; N/A; 6647Understandingthe fundamentals of communication among neurons, known as neuro-spike communication, leads to reach bio-inspired nanoscale communication paradigms. In this paper, we focus on a part of neuro-spike communication, known as axonal transmission, and propose a realistic model for it. The shape of the spike during axonal transmission varies according to previously applied stimulations to the neuron, and these variations affect the amount of information communicated between neurons. Hence, to reach an accurate model for neuro-spike communication, the memory of axon and its effect on the axonal transmission should be considered, which are not studied in the existing literature. In this paper, we extract the important factors on the memory of axon and define memory states based on these factors. We also describe the transition among these states and the properties of axonal transmission in each of them. Finally, we demonstrate that the proposed model can follow changes in the axonal functionality properly by simulating the proposed model and reporting the root mean square error between simulation results and experimental data.Publication Open Access A comparative study on GaSb epilayers grown on nominal and vicinal Si(100) substrates by molecular beam epitaxy(Institute of Physics (IOP) Publishing, 2020) Arpapay, Burcu; Suyolcu, Y. Eren; van Aken, Peter A.; Gülgün, Mehmet Ali; Serincan, Uğur; Çorapçıoğlu, Gülcan; n2STAR-Koç University Nanofabrication and Nanocharacterization Center for Scientifc and Technological Advanced ResearchThe direct growth of GaSb buffer layers on Si substrates is attracting considerable interest in the integration of group III-Sb based device structures on lower-cost Si substrates. Here, we present the effect of various growth steps on the defect types and defect density that are crucial for advancing high crystal quality GaSb buffer layer on nominal/vicinal Si substrate. As a growth step, the applied thermal annealing at an intermediate step provided a decrease in the threading dislocation (TD) density down to 1.72 x 10(8) cm(-2), indicating a more effective method compared to post-growth annealing. Additionally, the importance of period number and position of GaSb/AlSb superlattice layers inserted in GaSb epilayers is demonstrated. In the case of the GaSb epilayers grown on vicinal substrates, the APB density as low as 0.06 mu m(-1) and TD density of 1.98 x 10(8) cm(-2) were obtained for the sample grown on 4 degrees miscut Si(100) substrate.Publication Metadata only A comparison of parenting dimensions between deaf and hearing children(Sage Publications Inc, 2016) Ekim, Ayfer; N/A; Ocakçı, Ayşe Ferda; Faculty Member; School of Nursing; 1729Effective parenting is vital for intellectual, physical, social, and emotional development of a child. This study examined the differences between the parenting dimensions of deaf children and healthy ones. The sample of the study consisted of 292 children and their parents (146 of them deaf children and 146 of them healthy ones). Dimensions of parenting (warmth, rejection, structure, chaos, autonomy, and coercion) were measured using the Parent as Social Context Questionnaire. The mean scores of the positive parenting dimensions of warmth and autonomy of deaf children were significantly lower; however, the mean scores of the negative dimensions of chaos and coercion of deaf children were significantly higher than those of healthy ones. Deaf children can become successful adults with the help of their parents. Our results regarding parenting dimensions will be a guide for future nursing interventions planned to develop the relationships between deaf children and their parents.Publication Open Access A comparison of rates and severity of chronic kidney disease in deceased-donor and living-donor liver transplant recipients: times matter(TÜBİTAK, 2021) Yankol, Yücel; Bugeaud, Emily; Zens, Tiffany; Rizzari, Michael; Leverson, Glen E.; Foley, David; Mezrich, Joshua D.; D'Alessandro, Anthony M.; Acarlı, Koray S.; Fernandez, Luis A.; Mecit, Nesimi; Kanmaz, Turan; Andaçoğlu, Oya Münevver; Kalayoğlu, Münci; Faculty Member; School of Medicine; Koç University HospitalBackground/aim: the progression of chronic kidney disease (CKD) in recipients of living-donor liver transplant (LDLT) compared to deceased-donor liver transplant (DDLT) has not been studied in the literature. We hypothesize that CKD stage progression in LDLT recipients is reduced compared to that of their DDLT counterparts. Materials and methods: a retrospective study was undertaken including 999 adult, single-organ, primary liver transplant recipients (218 LDLT and 781 DDLT) at 2 centers between January 2003 and December 2012, in which CKD progression and regression were evaluated within the first 3 years after transplantation. Results: waiting time from evaluation to transplantation was significantly lower in LDLT patients compared to recipients of DDLT. CKD stage progression from preoperative transplant evaluation to transplantation was significantly greater in DDLT. Deceased-donor liver transplant recipients continued to have higher rates of clinically significant renal disease progression (from stage I-II to stage III-V) across multiple time points over the first 3 years posttransplant. Furthermore, a greater degree of CKD regression was observed in recipients of LDLT. Conclusion: it can be concluded that LDLT provides excellent graft and patient survival, significantly reducing the overall incidence of clinically significant CKD stage progression when compared to DDLT. Moreover, there is a significantly higher incidence of CKD stage regression in LDLT compared to DDLT. These observations were maintained in both high and low model for end-stage liver disease(MELD)populations. This observation likely reflects earlier access to transplantation in LDLT as one of the contributing factors to preventing CKD progression.Publication Open Access A comparison of the LVDP and {\Lambda} CDM cosmological models(Springer, 2012) Department of Physics; Akarsu, Özgür; Dereli, Tekin; Faculty Member; Department of Physics; College of Sciences; N/A; 201358We compare the cosmological kinematics obtained via our law of linearly varying deceleration parameter (LVDP) with the kinematics obtained in the Lambda CDM model. We show that the LVDP model is almost indistinguishable from the Lambda CDM model up to the near future of our universe as far as the current observations are concerned, though their predictions differ tremendously into the far future.Publication Metadata only A correlation-based and spectrum-aware admission control mechanism for multimedia streaming in cognitive radio sensor networks(Wiley, 2017) Hosseini, Elahe S.; Esmaeelzadeh, Vahid; Berangi, Reza; Department of Electrical and Electronics Engineering; Akan, Özgür Barış; Faculty Member; Department of Electrical and Electronics Engineering; College of Engineering; 6647Bandwidth management and traffic control are critical issues to guarantee the quality of service in cognitive radio networks. This paper exploits a network load refinement approach to achieve the efficient resource utilization and provide the required quality of service. A connection admission control approach is introduced in cognitive radio multimedia sensor networks to provide the data transmission reliability and decrease jitter and packet end-to-end delay. In this approach, the admission of multimedia flows is controlled based on multimedia sensors' correlation information and traffic characteristics. We propose a problem, connection admission control optimization problem, to optimize the connection admission control operation. Furthermore, using a proposed weighting scheme according to the correlation of flows issued by multimedia sensors enables us to convert the connection admission control optimization problem to a binary integer-programming problem. This problem is a kind of a Knapsack problem that is solved by a branch and bound method. Simulation results verify the proposed admission control method's effectiveness and demonstrate the benefits of admission control and traffic management in cognitive radio multimedia sensor networks.Publication Metadata only A cross sectional study evaluating the relationship of acne to androgenetic alopecia subtype and severity(Springer, 2024) Kazan, Didem; Gencebay, Gullu; Caf, Nazli; Esen, Beril Kara; Oba, Muazzez Cigdem; Özkoca, Defne; Koç University HospitalThe circulating androgens have a role in the pathogenesis of both acne vulgaris and androgenetic alopecia; an association between these two have been found previously. The aim of this study is to investigate the relationship of the severity of acne vulgaris lesions to the subtype of AGA; and to validate the relationship between severities of acne vulgaris and AGA. This study was conducted cross-sectionally at five different dermatology clinics. Male and female androgenetic alopecia patients with comorbid acne vulgaris have been included. The age, gender, severity of acne lesions, subtype of androgenetic alopecia and the severity of androgenetic alopecia were noted. The severity of acne lesions were graded according to the Global Acne Severity Scale and androgenetic alopecia was graded according to the Hamilton and Ludwig Scales. SPSS v 21 was used for the statistical analysis. A total of 101 patients have been included (12 male and 89 female). The mean age of the patients with severe acne was statistically significantly lower (p = 0.020). The difference in terms of gender was statistically insignificant (p = 0.388). The severity of acne vulgaris was found to be independent of the severity and of the subtype of AGA; p = 0.623 and 0.870 respectively. Neither a relationship between the severity of androgenetic alopecia and severity of acne; nor a relationship between acne severity and androgenetic alopecia subtype were found in this study. Thus we report that, acne severity is independent of the subtype and stage of the co-existing androgenetic alopecia.Publication Metadata only A deformation-based approach to tuning of magnetic micromechanical resonators(2018) Yalçınkaya, Arda D.; Department of Mechanical Engineering; N/A; Department of Mechanical Engineering; Biçer, Mahmut; Esfahani, Mohammad Nasr; Alaca, Burhanettin Erdem; Researcher; PhD Student; Faculty Member; Department of Mechanical Engineering; Koç University Surface Science and Technology Center (KUYTAM) / Koç Üniversitesi Yüzey Teknolojileri Araştırmaları Merkezi (KUYTAM); College of Engineering; Graduate School of Sciences and Engineering; College of Engineering; N/A; N/A; 115108Resonance frequency tuning in magnetic micromechanical resonators remains a primary field of study for frequency reference applications. The use of magnetic micromechanical resonators for innovative timing, oscillator and sensing applications necessitates a platform for the precise control of the resonance frequency. The present work addresses a deformation based technique for tuning the resonance frequency of nickel micromechanical resonators. Frequency response is measured through magnetic actuation and optical readout. The tuning approach is based on a combination of flexural deformation and uniaxial strain. The bending deformation is achieved by using a DC current through the microbeam. This magnetomotive mechanism reduces the resonance frequency by about 13% for a maximum DC current of 80 mA. A substrate bending method is used for applying uniaxial strain to increase the resonance frequency by about 8%. A bidirectional frequency modulation is thus demonstrated by utilizing both deformation techniques. The interpretation of results is carried out by finite element analysis and electromechanical analogy in an equivalent circuit. Using deformation techniques, this study provides a rigorous approach to control the resonance frequency of magnetic micromechanical resonators.Publication Metadata only A developmental study of glutamatergic neuron populations in the ventrobasal and the lateral geniculate nucleus of the thalamus: Comparing Genetic Absence Rats from Strasbourg (GAERS) and normal control wistar rats(Elsevier, 2017) Kirazhi, Ozlem; Yildizel, Sercan; Onat, Filiz; Kaptanoglu, Erkan; Çavdar, Safiye; Faculty Member; School of Medicine; 1995An imbalance of GABAergic inhibition and glutamatergic excitation is suspected to be the cause of absence epileptic seizures. Absence seizures are known to be generated in thalamocortical circuitry. In the present study we used light microscopy immunohistochemistry to quantify the density of glutamate+ve neurons at two developmental stages (P10 and P60) in two thalamic nuclei, the ventrobasal (VB) and lateral geniculate nucleus (LGN) in Wistar rats and compared the results with similar data obtained from genetic absence epilepsy rats from Strasbourg (GAERS). Rats were perfused transcardially with glutaraldehyde and paraformaldehyde fixative, then samples from VB and LGN were removed from each animal and sectioned. The glutamatergic neurons were labelled using light-microscopic glutamate immunohistochemistry. The disector method was used to quantify the glutamate+ve neurons in VB and LGN of GAERS and Wistar rats. The data were statistically analyzed. The distribution of the glutamate+ve neurons in the VB thalamic nucleus showed a significant reduction in the neuronal profiles per unit thalamic area from P10 to P60 in both Wistar and GAERS. The decrease was greater in the GAERS compared to the Wistar animals. However, in the LGN no reduction was observed either in the Wistar or in the GAERS. Comparing the density of glutamate+ve neurons in the VB thalamic nucleus of P10 of Wistar animals with of P10 GAERS showed statistically significant greater densities of these neurons in GAERS than in the Wistar rats. However no significant difference was present at P60 between the Wistar and GAERS animals. The disproportional decrease in GAERS may be related to the onset of absence seizures or may be related to neurogenesis of absence epilepsy. (C) 2016 ISDN. Published by Elsevier Ltd. All rights reserved.