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Bu tez çalışmasında yer elması dilimlerinin (Helianthus tuberosus L.) farklı kurutma yöntemleriyle kurutulması ve kurutma sonundaki ürünün kalite kriterleri incelenmiştir. Yer elması dilimlerinin kurutma sırasında çalışılacağı kalınlığı belirlemek amacıyla ön denemeler yapılmıştır. Ön denemelerle 3, 4, 5 mm kalınlıklarında 60˚C sıcaklıkta nem miktarı % 10'un altında olacak şekilde kurutulmuşlardır. Kurutma sırasında belirli aralıklarla dilimlerin nem içeriği ölçülmüştür. Kurutma sonunda dilimlerin kuruma sürelerine ve tekstürel özelliklerine göre değerlendirilerek asıl denemelerde kullanılacak dilimin kalınlığı 4 mm olacak şekilde çalışılmaya karar verilmiştir. Örnekler sıcak hava ile 60, 70, 80˚C sıcaklıkta sırasıyla 140, 108, 90 dakika, mikrodalga ile 180, 360, 600W gücünde sırasıyla 90, 35, 20 dakika, vakum ile 60˚C sıcaklıkta 550 mmHg basınçta 125 dakika ve liyofilizasyon ile -55˚C sıcaklıkta 1080 dakikada, 6,66 Pa basınçta kurutulmuştur. Kurutmanın belirli aşamalarında örneklerde ağırlık ölçümü yapılmıştır. Kurutmanın sonunda örneklerde suda çözünür kuru madde (Briks), nem içeriği, toplam kuru madde, kül, pH, titrasyon asitliği (TA), askorbik asit, rehidrasyon kapasitesi, büzülme, CIE LAB L* , a* , b* değerleri ile toplam renk değişimi, ΔE, esmerleşme indeksi, su aktivitesi(aw), toplam fenolik madde, antioksidan kapasitesi parametreleri belirlenmiştir. Bunların yanı sıra son üründe tekstürel ve duyusal analizler gerçekleştirilmiştir. Örneklerde kuruma periyodu, vakum ve mikrodalga ile kurutulanlarda sabit ve azalan hızda, sıcak hava ve liyofilizasyon ile kurutulanlarda ise azalan hız kuruma periyodu şeklinde gözlenmiştir. Etkin difüzyon katsayısı 0,27x10-8 m2/s ile 12,2x10-8 m2/s arasında bulunmuştur. Dilimlerin kurutma sonrası aw değerleri 0,52-0,63-arasında ölçülmüştür. Askorbik asit 2,19-4,26 arasında gözlemlenmiştir. Askorbik asit miktarının kuruma süresince azaldığı görülmüştür. En az değişim ise liyofilizasyonla kurutulan dilimlerde tespit edilmiştir. Kurutma sonrası renk içeriği CIE LAB L* , a* , b* değerleri ölçülmüş ve değerler gruplar arası farklılık göstermiştir. Esmerleşme indeksi 16,93-53,08 arasında gözlemlenmiştir. Esmerleşme indeksi kuruma süresince azalmıştır. Toplam renk değişimi 8,22-25,44 arasında gözlemlenmiştir, en fazla 600 W gücünde mikrodalgada kurutulan örneklerde tespit edilmiştir. Kurutulan örneklerde büzüşme % 32,29-57,97 arasında ölçülmüştür. En fazla büzüşme, 180 W gücünde mikrodalga ile kurutulan örneklerde görülmüştür. Örneklerde rehidrasyon içeriği 0,44-0,90 arasında değişmektedir, en yüksek rehidrasyon kapasitesi 60˚C sıcaklıkta vakumla kurutulan örneklerde gözlenmiştir. Örneklerde antioksidan miktarı 3,87-8,25 arasında değişmektedir, kurutmaya bağlı olarak azalmıştır. Antioksidan miktarında en az değişim liyofilizasyonla kurutulan örneklerde gözlenmiştir. Kurutma süresince dilimlerin toplam fenolik madde miktarını 2,59-7,49 arasında değişmektedir. En az değişimi liyofilizasyonla kurutulan örneklerde görülmüştür. Renk, görünüş, sertlik, çiğnenebilirlik, yapışkanlık, karamelize tat ve genel beğeni parametreleri ile yapılan duyusal analiz sonuçlarına göre en yüksek genel beğeniyi 4,37 değeriyle liyofilizasyonla kurutulan örnekler almıştır. Anahtar Kelimeler: Yer elması, kurutma, mikrodalga, vakum, liyofilizasyon, In this thesis study, different drying drying processes of Jerusalem artichoke fruit (Helianthus tuberosus L.) and the product criteria at the end of drying were examined. Preliminary trials were made to determine the thickness of Jerusalem artichoke fruit during drying. With preliminary tests, they were dried in 3, 4, 5 mm thickness and at a temperature of 60˚C with a moisture content below 10%. During drying, the moisture content of the fruit was measured at regular intervals. At the end of drying, it was decided to work with the thickness of the fruit to be 4 mm to be used in the actual trials, by evaluating the drying times and textural properties of the fruits. Samples with hot air at 60, 70, 80˚C for 140, 108, 90 minutes, with microwave 180, 360, 600 W power, 90, 35, 20 minutes, vacuum at 60˚C, 125 minutes at 550 mmHg pressure and dried by lyophilization at -55˚C for 1080 minutes at a pressure of 6,66 Pa. In certain stages of drying, weight measurements were made in the samples. At the end of drying, water soluble dry matter (°Briks), moisture content, total dry matter, ash, pH, titratable acidity (TA), ascorbic acid, rehydration capacity, shrinkage, CIE LAB L* , a* , b* values and total color change, ΔE, browning index, water activity (aw), total phenolic substance, antioxidant capacity parameters were determined. In addition to these, textural and sensory analyzes were performed in the final product. In the samples, the drying period was observed as a constant and decreasing speed in vacuum and microwave dryers, and a decreasing speed in drying with hot air and lyophilisation. The effective diffusion coefficient was found between 0,27x10-8 m2/s and 12,2x10-8 m2/s. After drying, the aw values of the fruits were measured between 0,52-0,63. Ascorbic acid has been observed between 2,19-4,26. It was observed that the amount of ascorbic acid decreased during the drying process. The least change was detected in fruits dried by lyophilization. Color determination after drying CIE LAB L *, a *, b * values were measured and the values differed between the groups. Browning index was observed between 16,93 and 53,08. st change in the amount of antioxidants was observed in samples dried by lyophilization. Browning index decreased during drying. The total color change was observed between 8,22-25,44, it was determined in samples that were dried in microwave at a maximum power of 600 W. Shrinkage in the dried samples was measured between 32,29-57,97%. The highest shrinkage was seen in the samples dried with a 180 W microwave. The rehydration content in the samples ranges between 0,44-0,90, the highest rehydration capacity was observed in samples that were vacuum dried at 60˚C. The amount of antioxidants in the samples ranged from 3.87-8.25, it decreased due to drying. The least change in the amount of antioxidants was observed in samples dried by lyophilization. During the drying period, the total phenolic content of the fruits varies between 2,59-7,49. The least change was seen in samples dried by lyophilization. According to the results of the sensory analysis made with the parameters of color, appearance, hardness, chewiness, stickiness, caramelized taste and general taste, samples dried by lyophilization received the highest overall taste with a value of 4,37. Keywords: Jerusalem artichoke, drying, microwave, vacuum, lyophilization, Tez (Yüksek Lisans) - Süleyman Demirel Üniversitesi, Fen Bilimleri Enstitüsü, Gıda Mühendisliği Anabilim Dalı, 2021., Kaynakça var.

Bu çalışmada fen ve teknoloji öğretmen adaylarının fen okuryazarlığı ile ilgili görüşleri tespit etmek amaçlanmıştır. Çalışmada nitel araştırma yöntemlerinden fenomenoloji yöntemi kullanılmıştır. Araştırmanın çalışma grubunu Amasya Üniversitesi Eğitim Fakültesi Fen ve Teknoloji öğretmenliği 4. sınıfta öğrenim gören ve ölçüt örnekleme yöntemi ile seçilen 5 öğretmen adayı oluşturmaktadır. Çalışmadaki veri toplama aracı olarak yarı yapılandırılmış mülakat formu kullanılmıştır. Mülakattan elde edilen bulgular NVIVO 9.0 programında kodlanarak anlamlı hale getirilmiştir. Mülakat analiz bulgularına göre, fen ve teknoloji öğretmen adaylarının fen okuryazarlığı ile ilgili bilgisi olmasına karşın fenle ilgili yayın takip etmedikleri, fen okuryazarlığını geliştirmede en önemli etkenin fen bilgisi öğretmeni olarak gördükleri, fen okuryazarlığının üst seviyelerini kazandırmak için programda değişiklik yapılması varılması gerektiği sonucuna varılmıştır., The purpose of this study is to identify the teacher candidates’ views on scientific literacy concept. In this study, the phenomenology method was used. The sample group, which is selected through the criterion sampling method, included five teacher candidates enrolled in Science and Technology Teaching program of Faculty of Education in Amasya University in 2012-2013 academic year. In this study, the data was collected with semi-structured interview form. The obtained data from the interviews were coded by using NVivo 9.0 software program. According to the findings, even though science and technology teacher candidates have a knowledge about scientific literacy they do not follow the publication about science. Furthermore, they see the science teacher as the most important factor in developing the scientific literacy and believe some changes must be necessary in the program to rise the level to the upper levels of science literacy. At the end of the study, some suggestions were made.

Amaç: Bu çalışma Tıp Fakültesi 1. ve 6. Sınıf öğrencilerinde uyku kalitesi ve etkileyen faktörlerin araştırılması amacıyla yapılmıştır. Materyal ve Metodlar: Araştırmada 1. Ve 6. Döneme devam eden toplam 126 öğrenciye anket uygulanmıştır. Tanımlayıcı soruların ardından Pittsburgh Uyku Kalitesi Anketi, değerlendirmede ise Pittsburgh Uyku Kalitesi İndeksi kullanılmıştır. PUKI skor ortalama ve standart sapması, bağımsız değişkenlerle PUKI skor ortalamaları arasında student t testi, ki-kare testi kullanılmıştır.Bulgular: Katılımcıların % 73,0’ünün PUKİ skorları 5 ve daha büyük olup kötü uyku kalitesine sahiptirler. Araştırmaya katılan tıp fakültesi öğrencilerinin % 30,2’si sigara kullanmaktadır. PUKİ skor ortalaması, sigara kullananlarda 7,18 ( ± 2,46 ), kullanmayanlarda 5,80 ( ± 2,68 )’dir ve gruplar arasında istatistiksel olarak anlamlı fark vardır ( t = 2,736 – p < 0,05 ). Gece saat 24.00’den sonra yatanlar, 15 dakikadan fazla sürede uykuya dalanlar ve gece uykusu 7 saatten az sürenlerde olanların uyku kalitesi anlamlı düzeyde düşük bulunmuştur. Sonuç: Maltepe Üniversitesi Tıp Fakültesi 1. Ve 6. Dönem öğrencilerinde genel olarak uyku kalitesi düşük bulunmuştur. Sigara kullanımı, kötü uyku kalitesinin nedenlerinden biridir. Öğrencilerin yaşadıkları metabolik ve psikososyal sorunlar uyku bütünlüğünü ve uyku süresini olumsuz etkilemekte ve kötü uykuya sebep olmaktadır. Sağlıklı ve düzenli yaşam tarzına sahip olarak uyku kalitesini etkileyen sorunlar ortadan kaldırılmalıdır., Aim: This study was carried out to investigate the sleep quality and affecting factors in Medical Faculty 1st and 6th grade students. Material and Methods: In the research, a questionnaire was applied to 126 students who continued in the 1st and 6th terms. Following the descritive questions, the Pittsburgh Sleep Quality Questionnaire was used, and the Pittsburgh Sleep Quality Index was used in the evaluation. PSQI score mean and standart deviation, Student t test, chi-square test were used between independent variables and PSQI score averages. Results: PSQI scores of 73,00% of the participants are 5 and above and they have poor sleep quality. 30,2% of medical students who participated in the study smoke. PSQI score average is 7,18 (± 2,46) for smokers and 5,80 ( ± 2,68 ) for non-smokers and there is statistically significant difference between groups ( t = 2,736 – p < 0,05 ). The quality of sleep was found to be significantly lower in those who sleep after 24.00 at night, fell asleep for more than 15 minutes, and those whose night sleep is less than 7 hours. Conclusions: The quality of sleep was generally low in Maltepe University Medical Faculty 1st and 6th term students. Smoking is one of the reasons for poor sleep quality. Metabolic and psychosocial problems experienced by students affect sleep integrity and sleep time negatively and cause bed sleep. Having a healthy and regular lifestyle, problems affecting sleep quality should be eliminated.

Due to copyright restrictions, the access to the full text of this article is only available via subscription. Percutaneous needle procedures are mostly carried out with the guidance of 2D ultrasound (US) imaging. US images are inherently noisy and their resolutions are low. Hence, target tracking can be challenging. Image based tracking methods can be used to track the needle and the target. This paper proposes visual tracking of multiple moving points, such as biopsy needles and targets, in 2D US images using normalized cross correlation and mutual information similarity functions. Both moving and deformable targets can be tracked. An affine motion model is used for small and moving target tracking and a thin plate spline motion model is used for deformable target tracking. During the tracking, needle and target template images are updated with a template update strategy. Also, tracking outputs of normalized cross correlation and mutual information are fused using the Kalman filter to reduce the tracking error. During the experiments, needle is inserted using a needle insertion robot. 2D US probe is attached to a robotic arm's end effector to servo the probe along the needle insertion path. Proposed needle and target tracking methods were tested with phantoms. Accuracies of the needle tip and moving target tracking methods were measured using an optical tracking system. Experimental results showed that the proposed tracking method could be used to simultaneously track the needle tip and the targets in real-time in 2D US guided percutaneous needle procedures. TÜBİTAK

Due to copyright restrictions, the access to the full text of this article is only available via subscription. Ultrasound (US) is one the most commonly used medical imaging techniques in percutaneous needle procedures. However, US images are inherently noisy and contain excessive number of artifacts. Hence, it is not easy to track the needle tip in the US images during the needle insertions. At this point, image based visual tracking techniques can be used for needle tip tracking. This paper presents a method for visual tracking of biopsy needles in 2D US images using sum of squared differences and sum of conditional variances. Second order Gauss-Newton optimization is used to decrease processing time and make the tracking more robust. The needle template images used in the method are updated with a strategy to prevent needle loss and detection failures during tracking. The paper also explains how to identify needle losses during tracking and how to recover the needle position without using a needle localization algorithm. We demonstrate the precision of the visual needle tip tracking method with experiments under challenging tracking conditions. TÜBİTAK

Due to copyright restrictions, the access to the full text of this article is only available via subscription. In this paper, real-time needle tip tracking method using 2D ultrasound (US) images for robotic biopsies is presented. In this method, the needle tip is estimated with the Gabor filter based image processing algorithm, and the estimation noise is reduced with the Kalman filter. This paper also presents the needle tip tracking simulation to test accuracy of the Kalman filter under position misalignments and tissue deformations. In order to execute proposed method in real-time, the bin packing method is used and the processing time is reduced by 56%, without a GPU. The proposed method was tested in four different phantoms and water medium. The accuracy of the needle tip estimation was measured with optical tracking system, and root mean square error (RMS) of the tip position is found to be 1.17 mm. The experiments showed that the algorithm could track the needle tip in real-time. TÜBİTAK

Due to copyright restrictions, the access to the full text of this article is only available via subscription. In the percutaneous needle procedures using ultrasound (US) imaging, the needle should be detected precisely to avoid damage to the tissue and to get the samples from the appropriate site. Excessive artifacts and low resolution of the US images make it difficult to detect the needle and its tip. It is possible to enhance the needle image using image processing; and this work proposes a novel needle detection method in 2D US images based on the Gabor filter. This method enhances the needle outline while suppressing the other structures in the image. First, the needle insertion angle is estimated and then the needle trajectory is found with the RANSAC line estimator. The experiments with three different phantoms showed that the algorithm is robust and could work in percutaneous needle procedures using US images. TÜBİTAK