40 research outputs found
Chaos from Massive Deformations of Yang-Mills Matrix Models
We focus on an Yang-Mills gauge theory in -dimensions with the
same matrix content as the bosonic part of the BFSS matrix model, but with mass
deformation terms breaking the global symmetry of the latter to . Introducing an ansatz configuration
involving fuzzy four and two spheres with collective time dependence, we
examine the chaotic dynamics in a family of effective Lagrangians obtained by
tracing over the aforementioned ansatz configurations at the matrix levels , for . Through numerical work, we
determine the Lyapunov spectrum and analyze how the largest Lyapunov
exponents(LLE) change as a function of the energy, and discuss how our results
can be used to model the temperature dependence of the LLEs and put upper
bounds on the temperature above which LLE values comply with the
Maldacena-Shenker-Stanford (MSS) bound , and below which it will
eventually be violated.Comment: 32+1 pages, 7 tables, 6 figures. Expanded discussion in section 3
establishing upper bound on temperature above which largest Lyapunov exponent
complies with the MSS bound, published versio
Chaos in Matrix Gauge Theories with Massive Deformations
Starting from an matrix quantum mechanics model with massive
deformation terms and by introducing an ansatz configuration involving fuzzy
four- and two-spheres with collective time dependence, we obtain a family of
effective Hamiltonians, and examine
their emerging chaotic dynamics. Through numerical work, we model the variation
of the largest Lyapunov exponents as a function of the energy and find that
they vary either as or , where
stand for the energies of the unstable fixed points of the phase
space. We use our results to put upper bounds on the temperature above which
the Lyapunov exponents comply with the Maldacena-Shenker-Stanford (MSS) bound,
, and below which it will eventually be violated.Comment: 17 pages, 2 figures, 5 tables, Talk given by S.
K\"{u}rk\c{c}\"{u}o\v{g}lu at the workshop on "Quantum Geometry, Field Theory
and Gravity", Corfu Summer Institute 202
Sedoanalgesia Administration with Propofol and Ketamine for Minor Urologic Interventions
Aim: In this study we aimed to administer sedoanalgesia with propofol and ketamine combination in patients undergoing planned minor urologic interventions with limited anesthesia. By combining these two medications, lower doses may be used, and we aimed to provide sufficient sedation, analgesia and amnesia without disrupting hemodynamic and respiratory stability and to increase patient and surgeon satisfaction. Material-Method: The study included 53 patients with planned minor urologic interventions aged from 19 to 85 years and physical situation ASA I-III. After six hours starvation, patients were taken to the surgery. Patients were monitored for electrocardiography (ECG), oxygen saturation (SPO2 ) and non-invasive blood pressure. For use if necessary a nasal O2 cannula was inserted. A vein in the back of the left hand was opened and 5 ml/min isotonic sodium chloride infusion was begun. Patient heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP) and oxygen saturation (SpO2 ) values were measured and a 5 point sedation scale (Table 1) was used to measure sedation scores. Basal values were recorded (0 min). Later patients were randomly divided into two groups with Group I administered intraurethral lidocaine gel for local anesthesia by the surgeon, while Group II were administered intravenous 0.015 mg/kg midazolam, 0.5 mg/kg 1% ketamine and 0.5 mg/kg 1% propofol by the authors for sedoanalgesia. At five minute intervals the HR, SAP, DAP, MAP, SpO2 values and sedation scores were measured and recorded. Results: Statistical evaluation found a statistically significant increase in SAP, DAP and MAP values measured at the 5th minute in Group I patients compared to preoperative values. In Group I patients, when the heart rate measured in the 1st and 5th minutes are compared with preoperative values there was a statistically significant increase identified. In Group II patients, there was a statistically significant fall in SpO2 values in the 1st and 5th minutes compared with preoperative values. When patient and surgeon satisfaction are compared with Group I, Group II was found to be statistically significantly higher. Though the blood pressure and heart rate increases in Group I patients were statistically significant, they were not at levels that required clinical intervention and/or treatment. Similarly the SpO2 decrease observed in Group II patients did not fall below 90% in any patient in spite of being statistically significant and rose again without clinical intervention and/or treatment. Conclusion: In this study we showed that sedoanalgesia administration with propofol and ketamine may be an alternative method for patients undergoing minor urology interventions that does not disrupt hemodynamic and respiratory stability, does not delay patient discharge, has low side effect incidence and has high patient and surgeon satisfaction
Historical development of non-formal environmental education in Turkey
Bu çalışma, 02-05 Mayıs 2012 tarihleri arasında Barcelona[İspanya]’da düzenlenen 4. World Conference on Educational Sciences (WCES)’da bildiri olarak sunulmuştur.The article discusses the periods of environmental education development in connection with internal social and international global influences, mainly the effect of the First United Nations Conference on Human environment in Stockholm 1972, the 1992 Earth Summit in Rio de Janeiro and the 2002 Earth Summit in Johannesburg. The article pays attention to the impact of the social background and the role of science and pedagogical research on the different stages in the curriculum and textbook development. The content of school subjects and educational technologies has also evolved towards student-centered interactive education in and out of school. From past to present, there have been many institutions in Turkey which provide environmental education. Some of these organizations most of whom work on a voluntary basis providing only informal training are: The Turkish Association for the Conservation of Nature (TTKD) 1955, World Wild Fund (WWF-DHKV) 1975, Research Association of Rural Environment and Forestry (KIRCEV) 1989, Directorate of Intramural Physical Education and Scouting (OBESID) 1989, The Foundation for the Protection and Promotion of the Environment and Cultural Heritage (CEKUL) 1990, The Turkish Foundation for Combating Soil Erosion, for Reforestation and the Protection of Natural Habitats (TEMA) 1992, Scouting and Guiding Federation of Turkey (TIF) 1992 and Nature Society, 2002. Although there are lots of studies carried out regarding the environmental education in Turkey, the studies regarding the topic started in real terms in 1999. The environmental education programs, conducted outside schools and the college systems, have been in operation in Turkey since 1999 and are carried out in collaboration with The Scientific and Technological Research Council of Turkey (TUBITAK), Universities, the General Directorate of National Parks and Environmental Protection and local authorities. The environmental education programs have 2 levels: theory and implementation. On the 'theory' level, experts in the field disseminate their knowledge of the features of the ecosystems of the protected sites and surrounding areas. On the 'implementation' level, all these features are studied in the field and the problems are identified and solutions are proposed. The target population of this environmental education project consists of teachers, scout leaders and those in post-graduate study. The program aims, through its teachings on nature, to popularize science among a wider population and to provide ways for the existing accumulation of knowledge to be used and implemented by this population. The program has provided a developmental framework for implementing field work and similar environmental education projects in the regions concerned and has brought about a more comprehensive and higher quality standard of education in the participating institutions. It is hoped that in the future the programs will reach more people and instill a lifelong desire, curiosity and motivation regarding ecosystems and the environment. Still there are many unsolved problems in environmental education.Acad World Educ & Res CtrNear E UniversityCyprus Educ Sci AssocBahçeşehir ÜniversitesiAnkara ÜniversitesiHacettepe Üniversites
Embrittlement in CN3MN Grade Superaustenitic Stainless Steels
Superaustenitic stainless steels (SSS) are widely used in extreme environments such as off-shore oil wells, chemical and food processing equipment, and seawater systems due to their excellent corrosion resistance and superior toughness. The design of the corresponding heat treatment process is crucial to create better mechanical properties. In this respect, the short-term annealing behavior of CN3MN grade SSS was investigated by a combined study of Charpy impact tests, hardness measurements, scanning and transmission electron microscopy. Specimens were heat treated at 1200 K (927 A degrees C) for up to 16 minutes annealing time and their impact strengths and hardnesses were tested. The impact toughness was found to decrease to less than the half of the initial values while hardness stayed the same. Detailed fracture surface analyses revealed a ductile to brittle failure transition for relatively short annealing times. Brittle fracture occurred in both intergranular and transgranular modes. SEM and TEM indicated precipitation of nano-sized intermetallics, accounting for the intergranular embrittlement, along the grain boundaries with respect to annealing time. The transgranular fracture originated from linear defects seen to exist within the grains. Close observation of such defects revealed stacking-fault type imperfections, which lead to step-like cracking observed in microlength scales
Classification of power quality disturbances by using ensemble technique [Güç Kalitesi Bozulmalarinin Birlikte Çalişma Yöntemi ile Siniflandirilmasi]
24th Signal Processing and Communication Application Conference, SIU 2016 -- 16 May 2016 through 19 May 2016 -- -- 122605In this paper, 11 different power quality disturbances were automatically detected by using statistical features with wavelet transform and norm entropy techniques. The best of the created features were selected with forward selection algorithm. Performance of classification algorithms, Support Vector Machines (SVM), Multi Layer Perceptron (MLP), k Nearest Neighbor (KNN) and random subspace KNN (Sub-KNN) which is an ensemble method, were examined. Consequently, the best classification accuracy of 99.3% was achieved by using Sub-KNN and it was appeared that compared to other methods, this algorithm was more robust against the noise. © 2016 IEEE
Chaotic Dynamics of the Mass Deformed ABJM Model
We explore the chaotic dynamics of the mass deformed ABJM model. To do so, we
first perform a dimensional reduction of this model from - to
-dimensions, considering that the fields are spatially uniform. Working in
the 't Hooft limit and tracing over ansatz configurations involving fuzzy two
spheres, which are described in terms of the GRVV matrices with collective time
dependence, we obtain a family of reduced effective Lagrangians and demonstrate
that they have chaotic dynamics by computing the associated Lyapunov spectrum.
In particular, we analyze in detail, how the largest Lyapunov exponent,
, changes as a function of . Depending on the structure of
the effective potentials, we find either or
, where is a
constant determined in terms of the Chern-Simons coupling , the mass ,
and the matrix level . Using our results, we investigate the temperature
dependence of the largest Lyapunov exponents and give upper bounds on the
temperature above which values comply with the MSS bound, , and below which it will eventually be violated.Comment: 35 pages, 8 figure
Can subtypes of white blood cells predict mortality in hemodialysis patients? [Beyaz kan hücre alt tipleri hemodiyaliz hastalari{dotless}nda mortaliteyi öngörebilir mi?]
Objective: To investigate whether increased white blood cell count (WBC) is an independent risk factor for mortality in hemodialysis (HD) patients. There are limited number of studies that evaluate the WBC subtypes and mortality in HD patients. Material and Methods: In this 36 months long prospective study, predictive value of WBC subtypes for mortality was investigated in 910 HD patients (male 55%, diabetes 29.3%, age 59 ± 14; HD duration 44 ± 39 months). Results: There was significant correlation between high sensitive C-reactive protein and neutrophils (r= 0.43, p< 0.001) and monocytes (r= 0.24, p< 0.001). During the study 202 (22%) patients died mainly of cardiovascular disease (%57). Survivals at 1,2 and 3 years were calculated with Kaplan Meier analysis and were found as 90%, 80% and %73, respectively. Kaplan Meier analysis showed that increased basal neutrophil count (>5.040/mm3), increased monocytes (>740/mm3) and decreased lymphocytes (<1.620/mm3) were correlated with poor survival. In Cox regression analysis, monocyte count over 1.267/mm3 and lymphocyte count less than 461/mm3 were found as independent factors for overall survival after correction for classical risk factors. However, neutrophil count was not correlated with mortality. Conclusion: Increased blood monocyte count and decreased lymphocyte count are independent risk factors for long-term mortality. © 2011 by Türkiye Klinikleri