Pre-Service Teachers\u27 Understanding of Geometric Reflections in Terms of Motion and Mapping View

In this manuscript, I describe a study of pre-service secondary mathematics teachers’ (PTs) understanding of geometric reflection in terms of a motion and a mapping views. PTs often have a motion view of geometric reflection based on their understanding of reflection line, domain, and plane. A motion view is a preliminary perspective developed prior to the construction of a mapping view. PTs need a mapping view of geometric reflection, and to be conscious of sub-concepts of a mapping view involved reflection line, domain, and plane. However, there is no clear evidence documenting how a learner’s motion view evolves to produce a mapping view. A clinical interview methodology was used to describe how mental structures occur in the movement between PTs’ motion view and the mapping view. Also, factors critical to the transition from a motion view to a mapping view were explored. Four case studies were constructed from transcript audio records, videos, and written works. Ongoing and retrospective analyses using Dubinsky’s action, process, object and schema (APOS) framework were used to examine PTs’ mental structures. The results indicated that the motion view transforms into the mapping view through the development of mental structures associated with three important sub-concepts of geometric reflection. These three sub-concepts are reflection line, domain, and plane. The results further indicated that there are series of factors that impact the development from the motion view to the mapping view. These factors are perpendicularity and equidistance properties, the role of reflection line, type of figures (circle, semicircle, interior and exterior points of the figures), the operational definition of the plane, and relations between figure and plane

Geometrik yansımayı anlama: John'un geometrik yansıma için öğrenme yolu

This study explores the development of a pre-service teacher’s mental structure from a motion view to a mapping view of geometric reflection. Many pre-service secondary mathematics teachers’ (PTs) understand geometric reflection as a motion rather than a mapping of a domain containing points in a plane relative to a reflection line, which is an essential understanding needed for teaching mathematics. Dubinsky’s action, process, object and schema (APOS) framework to document the transition of the PT’s (John’s) mental structures from a motion to a mapping view. Data from interview transcripts, videos, and written artifacts were analyzed using. Results indicated that John’s initial motion view of geometric reflection informed his evolving mapping view by developing sub-concepts of the reflection line, domain and plane. It is argued that the mapping view evolves from the motion view as the sub-concepts develop through successive challenges using figures and questioning. The study is a part of a larger study and was conducted with six PTs. However, it focuses on one of the PTs, John, who reached the mapping view of geometric reflection. The other PTs also demonstrated a similar mental structure.Bu çalışma, bir öğretmen adayının geometrik yansımayı anlamada ki zihinsel yapısının, hareket perspektifinden eşleştirme perspektifine gelişiminin araştırılması amacıyla yapılmıştır. Birçok ortaöğretim matematik öğretmeni adayı, geometrik yansımayı anlamada önemli olan yansıma ekseni, yansımanın etki alanı ve düzlem alt konseptlerine göre eşleştirme perspektifi yerine hareket perspektifine sahiptirler. Dubinsky'nin eylem, süreç, nesne ve sema (APOS) teorik çerçevesi kullanılarak bir öğretmen adayının (John) geometrik yansımayıanlamada ki zihinsel yapılarının hareket perspektifinden eşleştirme perspektifine gelişimleri incelenmiştir. Veri toplama araçları olarak mülakat transkriptleri, videolar ve çalışma kağıtları analiz edilmiştir. Bulgulara göre, John’un geometrik yansımayı anlamada sahip olduğu yansıma ekseni, yansımanın etki alanı ve düzlem hareket perspektifinden eşleştirme perspektifine geçişini hazırlanan mülakat soruları ve mülakat sürecinde sorulan açık-uçlu sorular kolaylaştırmıştır. Çalışma daha büyük bir çalışmanın parçasıdır ve altı öğretmen adayı ile yürütülmüştür. Diğer katılımcılarda hareket perspektifinden eşleştirme perspektifine benzer zihinsel yapı gelişimleri gösterdikleri için, çalışmada bir katılımcının zihinsel yapı gelişimleri detaylarıyla anlatılmıştır

İlk Dönem İslam Tarihinde Yargının Kurumsallaşmasında Dört Halifenin Rolü

Toplumda adaletin gerçekleşmesi hukuk kurallarına bağlıdır. Hukuk kurallarının uygulamaya dönüşmesi için yasama yetkisini elinde bulunduran erk tarafından yürürlüğe konularak kanun haline getirilmesi gerekmektedir. Kur’ân’ın emirlerinin bir gereği olarak Medine döneminde hukuk kuralları oluşturulmaya başlanmış ve bu kurallar ehil sahabeler aracılığı ile uygulamaya geçirilmiştir.Hz. Ebubekir Rasululullah döneminde uygulamaya konulan düzenlemeler devam ederken Hz. Ömer dönemi, yargının gelişimi ve kurumsallaşması yönünde en önemli dönüm noktasıdır. Halife Ömer adalete verdiği değerin bir parçası olarak yargının gelişmesi yönünde önemli çabalar sarfetmiş, genişleyen sınırlara bağlı olarak kurulan şehirler başta olmak üzere özel kadılar tayin etmeğe başlamıştır. Hz. Ömer başta yargı teşkilatı olmak üzere, tüm idari görevlileri dikkatle takip etmiş, onlara adaletin tam olarak gerçekleşmesi yönünde sürekli olarak bilgilendirici tavsiyeler göndermiştir. Onun bu tavsiye mektupları hala yargı tarihinde önemli bir konuma sahiptir. Hz. Ömer sonrası Hz. Osman dönemi ise mekansal anlamda yargının kurum kimliğini gösterdiği yıllardır. Bu anlamda Hz. Ali de yargının gelişimi yönünde önemli katkılar yapmıştır.Dört halife dönemi yargının yürütme ve yasamadan tam olarak ayrıldığı, yargı bağımsızlığının gerçekleştiği bir dönemdir. Bu dönem de halifeler bile bağımsız kâdılar tarafından yargılanmış, kararlar kendi aleyhlerine verilmiştir. Buna rağmen kâdıların bağımsızlığına bir zarar gelmemiş aksine ödüllendirilmiştir

Heat-resistant hydrophobic-oleophobic coatings

Thermally and chemically durable hydrophobic oleophobic coatings, containing different ceramic particles such as SiO2, SiC, Al 2O3, which can be alternative instead of Teflon, have been developed and applied on the aluminum substrates by spin-coating method. Polyimides, which are high-thermal resistant heteroaromatic polymers, were synthesized, and fluor oligomers were added to these polymers to obtain hydrophobic-oleophobic properties. After coating, Al surface was subjected to Taber-abrasion, adhesion, corrosion, and thermal tests. The effects of the particle size of ceramic powders, organic matrix, and heat on the coating material were investigated. Coating material was characterized by FTIR spectrophotometer. Surface properties and thermal resistance of the coating materials were investigated by SEM and TGA analyses. After thermal curing, contact angles of these coatings with H2O and n-hexadecane were measured. It was observed that coatings like ceramic particles are more resistant against scratch and abrasion than the other coatings. Also, they are harder than coatings, which do not include ceramic particles. It was seen that coatings, containing Fluorolink D10H, have high-contact angles with water and n-hexadecane

The formation of gradients in wet deposited coatings with photocatalytically active nanoparticles

A total of 81 doped and undoped anatase nano-particles were synthesised by a precipitation/co-precipitation process followed by a hydrothermal treatment to obtain increased visible light photocatalytic activity. The screening process was performed utilising a high throughput analysis system based on the photometric monitoring of the photocatalytic degradation of organic dyes (Rhodamine B, Malachite Green, Acid Blue 29). Photocatalytically active coatings were prepared with selected catalysts with high and low rankings from the screening. Degradation experiments with stearic acid could confirm the varying grades of visible light activity as seen in the screening process

Application of spray techniques for new photocatalytic gradient coatings on plastics

Transparent coating systems applicable on plastics surfaces by a spray technique are presented. The coatings are based on highly photocatalytically active nanoscaled titania powders, surface modified with silanes containing organic or fluoro-organic side chains. The modification allows for the introduction of the particles in organic inorganic hybrid NANOMER® coating systems. In the wet film—due to the evaporation of the solvents—a decompatibilisation of the coated particles to the matrix results in a self-organising gradient layer formation with an up-concentration of the active particles at the interface layer between coating and air. After activation by irradiation with artificial or natural UV-light, highly active transparent photocatalytic coatings for a great variety of materials are obtained

Exploring International Educators\u27 Learning About Local and Global Social Justice in a Virtual Community of Practice

In this chapter, the authors report themes that emerged when a cross-cultural team of researchers involved in a virtual international community of practice (Global Social Justice in Education-GSJE) investigated reflections on activities focused on social justice in local and global contexts. The findings suggested that the activities elicited GSJE community members\u27 understandings of the complexities of social justice associated with naming practices, privilege, and the arts within their own and across contexts. The authors discuss implications of the activities to advance diverse educators\u27 understanding of social justice in global and local contexts. They also unpack the opportunities and challenges that resulted from the collaborative research process and the writing of this chapter completed by the international author team comprised of 11 education scholars from seven countries

Maternal serum preptin levels in the pathogenesis and diagnosis of Gestational diabetes mellitus

Background: Gestational diabetes mellitus (GDM) is a metabolic disorder that occurs during pregnancy that increases both maternal and fetal mortality and morbidity. It was investigated whether there is a change in circulating levels of preptin, a new peptide secreted from pancreatic beta cells, due to GDM in pregnant women. The relationship between serum preptin levels with insulin and other metabolic parameters was also evaluated in these subjects. Methods: Eighty-five patients diagnosed as GDM and 89 healthy pregnant women with 75 mg oral glucose tolerance test (OGTT) was assessed in terms of serum preptin levels. Results: The serum preptin levels of the GDM group were significantly higher than those of the control group (p=0.001; p < 0.01). For the cutoff value of preptin measurement of 335.3 ng/L, the sensitivity was 97.65%, specificity was 87.64%, positive predictive value was 88.3% and negative predictive value was 97.5%. The risk of developing the disease is 294.273 times higher in patients with preptin level of 335.3 and above. Conclusions: We think that the reason for the increase in serum preptin levels in GDM is probably the response to glucose. The current results indicate that preptin plays an important role in elucidating the pathology of GDM. In addition, the search for a practical marker for the diagnosis of GDM suggests that the measurement of preptin level is promising

Real-world efficacy and safety of Ledipasvir plus Sofosbuvir and Ombitasvir/Paritaprevir/Ritonavir +/- Dasabuvir combination therapies for chronic hepatitis C: A Turkish experience

Background/Aims: This study aimed to evaluate the real-life efficacy and tolerability of direct-acting antiviral treatments for patients with chronic hepatitis C (CHC) with/without cirrhosis in the Turkish population.Material and Methods: A total of 4,352 patients with CHC from 36 different institutions in Turkey were enrolled. They received ledipasvir (LDV) and sofosbuvir (SOF)+/- ribavirin (RBV) ombitasvir/paritaprevir/ritonavir +/- dasabuvir (PrOD)+/- RBV for 12 or 24 weeks. Sustained virologic response (SVR) rates, factors affecting SVR, safety profile, and hepatocellular cancer (HCC) occurrence were analyzed.Results: SVR12 was achieved in 92.8% of the patients (4,040/4,352) according to intention-to-treat and in 98.3% of the patients (4,040/4,108) according to per-protocol analysis. The SVR12 rates were similar between the treatment regimens (97.2%-100%) and genotypes (95.6%-100%). Patients achieving SVR showed a significant decrease in the mean serum alanine transaminase (ALT) levels (50.90 +/- 54.60 U/L to 17.00 +/- 14.50 U/L) and model for end-stage liver disease (MELD) scores (7.51 +/- 4.54 to 7.32 +/- 3.40) (p<0.05). Of the patients, 2 were diagnosed with HCC during the treatment and 14 were diagnosed with HCC 37.0 +/- 16.0 weeks post-treatment. Higher initial MELD score (odds ratio [OR]: 1.92, 95% confidence interval [CI]: 1.22-2.38; p=0.023]), higher hepatitis C virus (HCV) RNA levels (OR: 1.44, 95% CI: 1.31-2.28; p=0.038), and higher serum ALT levels (OR: 1.38, 95% CI: 1.21-1.83; p=0.042) were associated with poor SVR12. The most common adverse events were fatigue (12.6%), pruritis (7.3%), increased serum ALT (4.7%) and bilirubin (3.8%) levels, and anemia (3.1%).Conclusion: LDV/SOF or PrOD +/- RBV were effective and tolerable treatments for patients with CHC and with or without advanced liver disease before and after liver transplantation. Although HCV eradication improves the liver function, there is a risk of developing HCC.Turkish Association for the Study of The Liver (TASL

Production of undoped and doped TiO2-particles and investigation of their photocatalytic activity

Im Rahmen dieser Arbeit wurden nano-TiO2-Partikel unter Rückfluss und durch Autoklavbehandlung hergestellt. Diese nano-TiO2-Partikel bestehen aus agglomeratfreien Anatas. Sie können ohne zusätzliche Dispergierhilfsmittel in unpolaren Lösungsmitteln wie Toluol und auch im Wasser dispergiert werden. Dotierungen des TiO2 sind durch Autolavbehandlung mit unterschiedlichen Dotiermitteln und Dotiermittelmengen durchgeführt worden. Die photokatalytischen Aktivitäten der dotierten nano-TiO2-Partikel sind durch Photodegradationen der vier unterschiedlichen Farbstoffe Rhodamin B, Acid Blue 29, Methylenblau und Malachitgrün unter Belichtung mit einem Sonnensimulator mit/ohne Kantenfilter ermittelt worden. Ein Hochdurchsatzverfahren zur schnellen Ermittlung der photokatalytischen Aktivitäten der hergestellten undotierten und dotierten nano-TiO2-Partikel wurde entwickelt. Die verwendeten Farbstoffe wurden meistens durch dotierte nano-TiO2-Partikel schneller photodegradiert als durch undotierte nano-TiO2-Partikel. Die Photodegradationsraten der Farbstoffe durch Nd(OEthOMe)3-, SnCl4-, MoCl4- und Ce(OEthOMe)4-dotierte nano-TiO2-Partikel wurden, besonders unter Belichtung mit sichtbarem Licht, erheblich verbessert. Wurden die unter Rückfluss hergestellten nano-TiO2-Partikel mit unterschiedlichen Substanzen 1-H,1-H,2-H,2-H-Perfluorooctyltriethoxysilan (FTS), Hexadecyltrimethoxysilan (HDTMS) und Palmitinsäure) Oberflächen modifiziert und die modifizierten nano-TiO2-Partikel anschließend in verschiedene NANOMER®-Systeme eingebaut, so sind TiO2-Gradienten innerhalb einer Schicht entstanden. Diese Gradientenbildung modifizierter TiO2-Partikel in den Schichten aus FTS-modifizierten nano-TiO2-Partikeln und verschiedenen Lacksystemen sind mittels SIMS-Tiefenprofil- und EDX/TEM-Analysen nachgewiesen worden. Wenn eine Schicht mit TiO2-Gradient belichtet wird, zeigt sie Superhydrophilie bzw. Selbstreinigungsfähigkeit.In this study firstly the TiO2-nanoparticles were synthesized by reflux and autoclave treatment. These nanoparticles were composed of agglomerate-free anatase. They could be dispersed in nonpolar solvent such toluene and also in water without any dispersion additive. In order to enhance the photoactivity of the TiO2 the particles of TiO2 were doped with various metalions by means of hydrothermal process. A high-throughput activity testing for the redispersed photocatalyst samples based on photometric monitoring of the photodegradation of three different organic dyes (Rhodamine B, Malachite Green, Acid Blue 29, Methylene Blue) after illumination by sun-tester light and cut-off filter (400 nm and 420 nm) restricted light was established. The photoactivity of the TiO2 under UV-illumination was enhanced by most of the used doping metalions. A greatest enhancements of the daylight photocatalytic activity were found for the samples doped with Nd(OEthOMe)3, SnCl4, MoCl4 and Ce(OEthOMe)4. The surface of highly dispersed TiO2 nanoparticles by the reflux treatment has been modified with 1-H,1-H,2-H, 2-H-Perfluorooctyltriethoxysilan, Hexadecyltrimethoxysilan und Palmitic acid. The surface-modified TiO2 nanoparticles have been suspended in the various NANOMER® systems. After applications of the suspensions on substrate by dip coating and subsequent curing the layer, the photocatalytically active layers were obtained. The analytical and microscopical investigations — SIMS-analysis and direct TEM imaging, supplemented by EDX have offered the formation of TiO2 gradients by modification of TiO2 nanoparticles within the composites during layer growth and curing. After the illumination of the layers with the TiO2-gradient were superhydrophilic respectively self-cleaning