A Comparison of Conventional and Computerized Cephalometric Methods

Aim:The aim of the present study was to compare the conventional method of manual cephalometric analysis with a computerized cephalometric analysis method.Subjects and Method:Lateral cephalometric radiographs of 31 patients (15 males and 16 females) were traced by two methods: (1) conventional; (2) computerized [Nemo Ceph NX 2006 (Nemo Tec, Madrid, Spain)] cephalometric analysis program. Four dental, 7 skeletal, and 3 soft tissue parameters, were measured by one investigator. Intra-class correlation coefficients were performed for both methods to assess the reliability of the measurements according to Houston method. The measurements determined by each method were compared with a paired t-test.Results:The correlation coefficient between the first and second measurements ranged from 0.77 to 0.95 (average: 0.86) for the conventional method and from 0.79 to 0.97 (average: 0.91) for the computerized method. The results of paired t-test showed that significant differences were observed for SNA (°) (P= 0.000), SNB (°) (P= 0.033), ANB (°) (P= 0.037), Witts appraisal (mm) (P= 0.001), FMA (°) (P= 0.026), Overbite (mm) (P= 0.000), U1-PP (°) (P= 0.026), and UL-E (mm) (P= 0.000).Conclusion:Intra-obsserver reliability for both methods was acceptable. Significant differences between conventional and computerized methods were observed for SNA, SNB, ANB, Witts appraisal, FMA, Overbite, U1-PP, and UL-E

Ilık Hidromekanik Derin Çekme Prosesinin Sonlu Elemanlar Analizi Ve Parametrik Optimizasyonu

Konferans Bildirisi -- Teorik ve Uygulamalı Mekanik Türk Milli Komitesi, 2015Conference Paper -- Theoretical and Applied Mechanical Turkish National Committee, 2015Bu çalışmada otomotiv sanayiinde taşıt ağırlığını azaltmak için giderek artan şekilde kullanılan alüminyum alaşımlarının şekillendirilmesinde kullanılan geleneksel yöntemlerin yerini almaya başlayan ılık hidromekanik derin çekme prosesinin kapsamlı bir sonlu elemanlar modeli oluşturulmuştur. Farklı eleman sayıları ve eleman formülasyonları, temasta bulunan bileşenler için farklı sürtünme katsayıları ve malzeme modelleri sistematik bir şekilde denenerek sonlu eleman modeli için en uygun tercihler ve değerler belirlenmeye çalışılmıştır. Çalışmanın ikinci kısmında ise, oluşturulan sonlu elemanlar modeli ile ılık hidromekanik derin çekme işlemindeki takım sıcaklıklarının ve yükleme profillerinin (hidrolik basıncı ve baskı plakası kuvveti) en iyi şekillendirilebilirliği veren değerleri belirlenmeye çalışılmıştır. Bu çalışmalar neticesinde, malzeme davranışını en iyi elastik-viskoplastik-termal malzeme modelinin yansıttığı belirlenmiştir. Coulomb sürtünme katsayıları sac-kalıp ara yüzeyi için 0.05, sac-baskı plakası için 0.05 ve sac-zımba sürtünme yüzeyleri arasında 0.25 olarak tespit edilmiştir. En iyi şekillendirmenin sağlanabilmesi için kalıp ve zımbaya ait sıcaklık değerleri sırasıyla 300 ve 25 °C olarak belirlenmiştir. Hidrolik basıncın baskı plakasının kuvvetine göre daha etkin bir parametre olduğu görülmüştür.In current study, a comprehensive finite element modeling was established for warm hydromechanical deep drawing process which is a promising technique in forming of aluminum alloys that are expected to be increasingly exploited in automotive industry along with lightweighting efforts. Different number of elements and element formulations, coefficients of friction for contacting surfaces and material models were systematically tested and optimum choices and values were determined. In the second part of the study, optimum tool temperature, and loading profiles (hydraulic pressure and blank holder force) were obtained parametrically to achieve highest formability in warm hydromechanical deep drawing process by using established FE model. As a result, elastic-viscoplastic-thermal material model was found to be reflecting the material behavior better compared to other material models utilized. Coulomb friction coefficient for contacting surfaces blank-die, blank-blank holder and blank-punch were determined as 0.05, 0.05 and 0.25, respectively. Optimal temperatures values for die and punch were determined as 300 and 25°C, respectively when highest formability is taken into account. Hydraulic pressure was found to be more effective on formability than blank holder force

Skeletal Age Assessment According to The Greulich and Pyle Atlas in Different Skeletal Malocclusions

Aim:To compare the skeletal age (SA) of the patients with and without different sagittal skeletal malocclusions of the jaws and to compare differences between males and females.Subjects and Methods:The sample comprised 120 patients (mean age 12.00±1.10) referred to our clinic. SA from the conventional roentgenograms of left hands and wrists by using the atlas of GP standards for each gender and skeletal class was estimated. The comparisons among the skeletal classes were done by means of the one way ANOVA test for both genders. Tukey post hoc test was used to determine the individual differences. The mean differences between the SA and chronological age (CA) of the subjects in each group were tested by means of paired t-test.ResultsMean SA for females with Class I, II, and III malocclusions were advanced 0.43, 0.22, and 0.61 years than mean CAs, respectively (P=0.051, P=0.228, and P=0.003). The mean difference between CA and SA for males with Class I, II, and III malocclusions were −0.14, −0.35, and 0.24 years, respectively (P=0.502, P=0.028, and P=0.088). The mean difference for males with Class II (−0.35±0.65) and Class III (0.24±0.59) malocclusions was statistically significant.Conclusion:These results suggest that patients with different skeletal malocclusions may have a different rhythm of skeletal maturation from that of children without malocclusions

Young Double Slit Interference Effects at Quantum Level

The currently accepted model for quantum interference resulting from the emission of electron waves from two scattering centers induced by either light or charged particle impact is analogous to Young\u27s emission of two light waves from two slits. In this work we show that this simple classical wave model is incomplete and that there is a more complicated quantum interference pattern for low energy ionization caused by electron impact

Geri Dönüşüm Lifler İçeren Süprem Kumaşların Isıl Konfor Özelliklerinin İncelenmesi

Bu çalışmada orijinal (ORJ) ve geri dönüşüm (GD) pamuk lifleri kullanılarak, %100 ORJ, %100 GD ve 50/50 ORJ/GD pamuk lifleri içeren iplikler üretilmiş ve bu iplikler ile üretilen süprem kumaşların ısıl konfor özellikleri incelenmiştir. Bu amaçla konfeksiyonda açığa çıkan kumaş kırpıntılarından elde edilen geri dönüşüm pamuk lifleri ve orijinal pamuk lifleri open-end rotor iplik eğirme sisteminde eğrilmiş ve bu ipliklerden süprem kumaşlar üretilmiştir. Geri dönüşüm ve orijinal pamuk ipliklerinden elde edilen bu kumaşların ısıl konfor özelliklerini karşılaştırmak amacıyla; ısıl iletkenlik, ısıl direnç, ısıl soğurganlık ve hava geçirgenlik özellikleri ölçülmüştür. Kumaşlarda geri dönüşüm pamuk liflerinin kullanımının kumaşların ısıl direnç değerlerini arttırdığı; ısıl iletkenlik, hava geçirgenliği ve ısıl soğurganlık değerlerini düşürdüğü gözlenmiştir. Geri dönüşüm liflerinden örülmüş süprem kumaşların ısıl direnç değerlerinin yüksek olmasının ve ilk temasta daha sıcak bir his vermesinin orijinal liflerden üretilen kumaşlara göre kullanım alanına bağlı olarak üstünlük sağladığı düşünülmektedir

Effects of The Maxillary Molar Distalization with Zygoma-Gear Appliance on Maxillary Third Molars

Aim:The aim of the present study was to evaluate the effects of a newly produced appliance, named as Zygoma-Gear Appliance (ZGA), on maxillary third molars. We also investigated the effects of ZGA on skeletal, dentoalveolar, and soft tissue measurements.Subjects and Methods:The study group included 10 patients (mean age: 18.3±1.8 years) treated with ZGA system supported with zygomatic anchorage miniplates. The changes due to the distalization were evaluated from the lateral cephalometric films taken before and after distalization by means of Paired t-test.Results:The mean treatment period to achieve a Class I molar relationship was 7.9±3.1 months. The distalization amount of the maxillary molar teeth was 3.8±2.1 mm (p 0.05).Conclusions:Maxillary molar distalization without anchorage loss was achieved with ZGA. Maxillary third molars were slight affected by the distalization force

Effects of Systemic and Local Interferon Beta-1a on Epidural Fibrosis

Study DesignLevel 1 randomized controlled study.PurposeTo investigate the effects of systemic and local interferon-beta-1a (IFN-β-1a) on prevention of epidural fibrosis using histopathological parameters.Overview of LiteratureEpidural fibrosis involves fibroblastic invasion of nerve roots into the epidural space. Formation of dense fibrous tissue causes lumbar and radicular pain. Many surgical techniques and several materials have been proposed in the literature, but no study has assessed the effect of IFN-β-1a on prevention of epidural fibrosis.MethodsForty-eight adult female Sprague-Dawley rats were divided into six groups of eight: sham group, control group, systemic 44 μg IFN-β-1a group and 22 μg IFN-β-1a group (after laminectomy and discectomy, 0.28 mL and 0.14 mL IFN-β-1a applied subcutaneously three times for a week, respectively), local 44 μg IFN-β-1a group (laminectomy and discectomy, followed by 0.28 mL IFN-β-1a on the surgical area), and local 22 μg IFN-β-1a group (laminectomy and discectomy, followed by 0.14 mL IFN-β-1a on the surgical area). All rats were sacrificed after 4 weeks and groups were evaluated histopathologically.ResultsCompared with sham and control groups, significantly less epidural fibrosis, dural adhesion, and fibroblast cell density were observed in the local and systemic 44 μg IFN-β-1a groups. No other differences were evident between the local and systemic groups.ConclusionsIFN-β-1a is effective in preventing epidural fibrosis with systemic and local application

Can elementary students gather information from concept maps ?

In this study, we investigated whether concept maps were used as often and as effectively in elementary science and technology classrooms as recommended by the National Ministry of Education (MEB) in the new curricula in Turkey. In the new elementary science and technology curricula, the MEB provides a general concept map for each unit. We used concept maps provided for the Light and Sound units for fourth, fifth, and sixth grades as content to determine whether students were able to use concept maps to gather information from them. Our analyses showed that most of the students did not use the concept maps to answer the questions. Rather they used their own knowledge and cognitive structures about light and sound to answer the questions. Therefore, we concluded that students do not know how to read the concept maps and gather knowledge from them. Also, we ran an Analysis of Variance (ANOVA) test to explore whether grade level has an effect on students? performance in reading the concept maps and gathering information from them. We found that grade level has a significant effect on students? performance in using concept mapsIn this study, we investigated whether concept maps were used as often and as effectively in elementary science and technology classrooms as recommended by the National Ministry of Education (MEB) in the new curricula in Turkey. In the new elementary science and technology curricula, the MEB provides a general concept map for each unit. We used concept maps provided for the Light and Sound units for fourth, fifth, and sixth grades as content to determine whether students were able to use concept maps to gather information from them. Our analyses showed that most of the students did not use the concept maps to answer the questions. Rather they used their own knowledge and cognitive structures about light and sound to answer the questions. Therefore, we concluded that students do not know how to read the concept maps and gather knowledge from them. Also, we ran an Analysis of Variance (ANOVA) test to explore whether grade level has an effect on students? performance in reading the concept maps and gathering information from them. We found that grade level has a significant effect on students? performance in using concept map

Sandıklı Bölgesindeki Kaynak, İçme ve Kaplıca Sularındaki Radyasyon Değişimi

In this study, we have measured the α/β concentration in drinking and thermal waters in Sandıklı, Afyon. Periodic samples are collected from 8 sources over sampling period 6 months. Samples are analyzed by WPC 9550 α/β proportional counter. We have compared the results with WHO (World Health Organization)’s standard recommendation results about drinking and thermal waters. In general, we found beta radioactivity values normal and alpha radioactivity values high