Prediction of extractives and lignin contents of Anatolian black pine (Pinus nigra Arnold. var pallasiana) and Turkish pine (Pnus brutia Ten.) trees using infrared spectroscopy and multivariate calibration

Thesis (Master)--İzmir Institute of Technology, Chemistry, İzmir, 2008Includes bibliographical references (leaves: 61-64)Text in English; Abstract: Turkish and Englishxi, 64 leavesDetermination of quality parameters such as extractives and lignin contents of wood by wet chemistry analyses takes long time. Near-infrared (NIR) and mid-infrared (MIR) spectroscopy coupled with multivariate calibration offer fast and nondestructive alternative to obtain reliable results. However, due to complexity of multi-wavelength spectra, wavelength selection is generally required. Turkish pine and Anatolian black pine are the most growing pine species in Turkey. Forest products industry has widely accepted use of these trees because of their ability to grow on a wide range of sites and their suitability to produce desirable products. Determination of extractives and lignin contents of wood provides information to tree breeders when to cut and on how much chemical is needed in pulping and bleaching process. In this study, 58 samples of Turkish pine and 51 samples of Anatolian black pine were collected to investigate the correlation between NIR and MIR spectra of these samples and their extractives and lignin contents which were determined with reference methods. Genetic inverse least squares (GILS) was used for multivariate calibration. Standard error of calibration (SEC) values were less than 1.86% (w/w) for lignin and 1.19% (w/w) for extractives whereas standard error of prediction (SEP) values were less than 3.81% (w/w) for lignin and 2.04% (w/w) for extractives. Resulting R2 values for calibrations were larger than 0.8. Classification for Turkish pine and Anatolian black pine samples was performed by genetic algorithm based principal component analysis (GAPCA) and these two pine species were classified by using NIR and MIR spectra

ANALYSIS OF THE RELATIONSHIP BETWEEN UNDERGRADUATE STUDENTS’ PHYSICS SUCCESSES AND THEIR ABILITIES

The purpose of this study was to identify the effects of student abilities on their learning processes and to determine what kind of students in terms of their abilities were more successful during physics teaching. In this direction, 156 students who took basic physics course in Atatürk University, Faculty of Education, in Departments of Physics, Science, Computer, and Mathematics teaching were included to the research scope. “Self-assessment inventory” that was developed by Kuzgun in 1988 was used to measure students’ abilities. The letter grades and raw scores that were received by students at the end of academic year were considered to determine students’ academic successes. Students’ academic successes were consisted of two exams. First one was a midterm exam that was organized in the middle of the terms and the other was final exam that was organized at the end of the term. The questions that were used in exams were prepared by researcher and reliability of tests was found as α=0,69. Descriptive analysis and correlation test were used for data analysis. As a result, it was found that student abilities affected academic successes and students who had numerical abilities had higher levels of physics successes.  Article visualizations

Problems related to voiding pattern in patients with hypospadias repair: i̇s the problem related to only operation?

Background: Problems related to the urine flow are rather common in hypospadias patients. As these problems are detected during follow-up of urine flow in the post-operative period, it is difficult to determine whether it is a problem emerging secondary to the surgery or it is a congenital condition. Objective: The objective of this study was to evaluate the lower urinary tract functions in hypospadias patients with pre-operative and post-operative uroflowmetric examinations and to determine whether it is a complication of the surgery or a congenital condition. Materials and Methods: A total of 63 patients who underwent hypospadias surgery and were monitored postoperatively between January 2012 and January 2013 were enrolled in the study. Data about the pre- and post-operative uroflowmetry parameters were collected and compared. Results: Of total 83 patients, only 63 (76.8%) patients, whose parent’s provided the written consent, were studied. The mean age was 6.9±2.4 years (3–14 years). The mean bladder volume estimated according to the age of the patients was 266.5±71.7 ml. The mean bladder volume before and after the surgery was 179±56 ml and 189±53 ml, respectively, and the bladder volumes were 67% and 71% of the estimated bladder volume, respectively. There was no significant difference between the bladder volumes measured before and after the surgery (p=0.159). Furthermore, no significant change in the measurements regarding the maximum flow rate, time to maximum flow rate, total time of the urine flow, mean flow rate, voided volume, voiding time, and post-void residual volume was observed. Conclusion: The uroflowmetry is an easy-to-use, non-invasive, and objective method, which can be used for the early diagnosis of the urethral stricture following the hypospadias surgery and the evaluation of the obstructions in the lower urinary trac

Direct Measure of Giant Magnetocaloric Entropy Contributions in Ni-Mn-In

Off-stoichiometric alloys based on Ni 2 MnIn have drawn attention due to the coupled first order magnetic and structural transformations, and the large magnetocaloric entropy associated with the transformations. Here we describe calorimetric and magnetic studies of four compositions. The results provide a direct measure of entropy changes contributions including at the first-order phase transitions, and thereby a determination of the maximum field-induced entropy change corresponding to the giant magnetocaloric effect. We find a large excess entropy change, attributed to magneto-elastic coupling, but only in compositions with no ferromagnetic order in the high-temperature austenite phase. Furthermore, a molecular field model corresponding to antiferromagnetism of the low-temperature phases is in good agreement, and nearly independent of composition, despite significant differences in overall magnetic response of these materials

Life balance and traumatic txperiences in undergraduate students living near conflict zones

This study aimed to examine the prevalence of PTSD among undergraduate students and how PTSD affected life balance of undergraduate students who live close to conflict zones. The participants of the study were 253 undergraduate students who lived close to conflict zone and witnessed or experienced bombing or war conflicts. Data collection instruments were Juhnke-Balkin Life Balance Inventory- Turkish Form and Turkish Version of the PTSD Checklist for Diagnostic and Statistical Manual of Mental Disorders Fifth Edition. The data were collected in paper-pencil format one month after bombing by terrorists across the border. Structural equation modeling was used in data analysis. The results indicated that PTSD symptomatology positively affects the students’ depression and sleep disturbance levels. However, PTSD symptomatology negatively affects global health and positive orientation. All effect sizes were in small to large range. We suggest that administrators should invest counseling services and have practioners providing help especially for undergraduate students in conflict zones; and to make families familiar with PTSD symptoms. © 2020, Springer Science+Business Media, LLC, part of Springer Nature

Calorimetric and magnetic study for Ni50_{50}Mn36_{36}In14_{14} and relative cooling power in paramagnetic inverse magnetocaloric systems

The non-stoichiometric Heusler alloy Ni$_{50}$Mn$_{36}$In$_{14}$ undergoes a martensitic phase transformation in the vicinity of 345 K, with the high temperature austenite phase exhibiting paramagnetic rather than ferromagnetic behavior, as shown in similar alloys with lower-temperature transformations. Suitably prepared samples are shown to exhibit a sharp transformation, a relatively small thermal hysteresis, and a large field-induced entropy change. We analyzed the magnetocaloric behavior both through magnetization and direct field-dependent calorimetry measurements. For measurements passing through the first-order transformation, an improved method for heat-pulse relaxation calorimetry was designed. The results provide a firm basis for the analytic evaluation of field-induced entropy changes in related materials. An analysis of the relative cooling power (RCP), based on the integrated field-induced entropy change and magnetizing behavior of the Mn spin system with ferromagnetic correlations, shows that a significant RCP may be obtained in these materials by tuning the magnetic and structural transformation temperatures through minor compositional changes or local order changes

Role of thermally-stable deformation twins on the high-temperature mechanical response of an austenitic stainless steel

In the present study, a two-step thermo-mechanical processing consisting of cold work and heat treatment steps was performed to increase the operating temperature of 316 austenitic stainless steels. A hierarchical microstructure of thermally-stable, nano twin bands was achieved forming into bundles in elongated grains. The mechanical response of the samples with this microstructure was evaluated through uniaxial tension tests at temperatures ranging from 20 °C to 500 °C and compared with those from the fully annealed samples. The results demonstrate that such hierarchical microstructure leads to a significant increase in the elevated temperature yield strengths due to the presence of nano-twin boundaries and resulting decrease in dislocation mean free path and increase in dislocation storage capacity. In fact, the yield strength ratio of the twinned and annealed samples increases with increasing temperature up to 500 °C, indicating the effectiveness of pre-existing thermally-stable twin boundaries as the strengthening source at temperatures as high as 0.46 homologous temperature. The hierarchical microstructure also led to irregular serrations through dynamic strain aging in the stress-strain response at 500 °C, which is attributed to the bi-modal microstructural length-scales present in the structure affecting the diffusion distances during dynamic strain aging. This structure also increases the tensile strength, and without a total loss in ductility, even though the flow stress of the twinned samples surpasses the tensile strength of the annealed samples, especially at elevated temperatures. Total hardening rate is consistently higher in the twinned samples as compared to the annealed samples, indicating the positive role of nano-twin boundaries in the dislocation storage capacity at elevated temperatures. Overall, the present study clearly demonstrate the positive role of thermally stable nano-twins on the elevated temperature mechanical response of austenitic stainless steels

Düşük Sosyoekonomik Düzeydeki Mahallede Bulunan Bir İlköğretim Okulunda Akademik Başarıyı Düşüren Faktörler Nelerdir?

This research was conducted in order to determine the factors negatively affecting academic achievement in a primary school located in a neighborhood consisting of families with low socioeconomic status in the city center of Erzurum, by a teacher working in that school and an academic of Ataturk University in 2011-2012 academic year. Case study was used as a research method, and interview technique as a data collection tool. The research was conducted with the participation of two administrators, eight teachers, five parents and five students from the school. As a result of the study, it was determined that the leading factor that negatively affected the academic achievement in a school located in a neighborhood with low socio-economic status was the socio-economic conditions of the families; which was followed by the settlement of the school, students, parents, teachers, school facilities and some characteristics of school administrators; respectively.Bu araştırma, Erzurum il merkezinde düşük sosyoekonomik düzeyli ailelerden oluşan bir mahallede bulunan ilköğretim okulunda, akademik başarıyı olumsuz yönde etkileyen unsurları tespit etmek amacıyla, o okulda çalışan bir öğretmen ve Atatürk Üniversitesinden bir öğretim üyesi tarafından, 2011-2012 öğretim yılında yapılmıştır. Araştırma yöntemi olarak örnek olay, veri toplama aracı olarak görüşme tekniği kullanılmıştır. Araştırma, çalışmanın yapıldığı okuldan iki idareci, sekiz öğretmen, beş veli ve beş öğrencinin katılımıyla gerçekleştirilmiştir. Araştırma sonucunda, düşük sosyoekonomik düzeydeki bir mahallede bulunan okulda, akademik başarıyı olumsuz yönde etkileyen unsurların başında ailelerin sosyoekonomik koşullarının geldiği; daha sonra sırasıyla okulun bulunduğu yerleşim biriminin, öğrencilerin, velilerin, öğretmenlerin, okulun fiziki olanaklarının ve okul idarecilerinin bazı özelliklerinin olduğu belirlenmiştir

Analysis of Factors Affecting Use of Bumble Bees for the Pollination in Glasshouse Tomatoes Growing

Bu çalışmada, Antalya ili Serik ve Merkez ilçede cam sera tek ürün domates yetiştiriciliğinde üreticilerin bombus arısı kullanımı üzerine etki eden faktörleri belirlemek için logistik regresyon kullanılmıştır. Modele açıklayıcı değişkenler olarak domates verimi, üreticinin; eğitim düzeyi, deneyimi, bombus arısı kullanımı konusundaki bilgi düzeyi, yeni teknolojileri kullanma düzeyi, işletmede uzmanlaşma yani serada çeşitli ürünlerin yetiştirilip yetiştirilmemesi ve yabancı işçilik masraf düzeyi dahil edilmiştir. Analiz sonucunda, domates verimi, üreticinin bombus arısı kullanımı konusundaki bilgi düzeyi, yeni teknolojileri kullanma düzeyi değişkenleri istatistiksel olarak önemli iken diğer değişkenler önemli bulunmamıştır. Modelde, sadece yabancı işçilik masraf düzeyi değişkeni negatif etkiye sahip olup diğerleri pozitif etkiye sahiptir.In the study, a binary logit model was employed to determine factors affecting the use of bumble bees for the pollination in glasshouse tomatoes production in Antalya province of Turkey. Tomatoes yield, education level of farmer, experience in greenhouse vegetable production, knowledge level of farmers about bumble bee using, adoption level of new other production technologies, specialization and level of hired labor cost were fitted in the model as explanatory variables. The results indicated that yield, knowledge level of farmers about bumble bee using, adoption level of new production technologies are statistically significant, while other variables are not. In the model, only level of hired labor cost variable is negatively and other variables are positively associated with the probability of bumble bee adoption