The effects of microlearning-supported flipped classroom on pre-service teachers' learning performance, motivation and engagement.

Flipped classroom (FC) has recently attracted researchers' interest in teacher education thanks to its potential for promoting pre-service teachers' (PTs) professional development. However, some of major issues are the lack of interactivity, disengagement, and amotivation of PTs for pre-class activities due to poor online instruction design. This explanatory sequential mixed study explores the effects of the microlearning-supported FC on PTs' learning performance for professional development, motivation, and engagement. A total of 128 PTs participated in this study from a university in Turkey. In the quantitative phase, a quasi-experimental pretest-posttest design was conducted and the treatment lasted for 14 weeks. The PTs were divided into two experimental groups and one control groups using random sampling technique. In first experimental group (m-FC, n = 43), the participants learned with microlearning-supported (by using a-bit sized learning chunks outside the classroom) FC model. In the second experimental group (t-FC, n = 39), the participants learned with traditional FC model. A control group (non-FC, n = 46) was not taught using FC model and teacher-centered approach was adopted in this group. The findings indicated that FC model (in both experimental groups) increased learning performance, intrinsic motivation, emotional, and behavioral engagement compared to a group that was not used to FC. Moreover, m-FC group had better intrinsic motivation and engagement than both t-FC and non-FC groups. Semi-structured interviews showed that two major themes emerged regarding benefits and challenges of microlearning-supported FC. Most of PTs had positive perceptions that it enhances the willingness to participate in pre-class activities. The implications for teacher education, recommendations and directions for further studies were also discussed.

The effects of prenatal and neonatal exposure to electromagnetic fields on infant rat myocardium.

INTRODUCTION: Electromagnetic fields (EMF) have adverse effects as a result of widespread use of electromagnetic energy on biological systems. The aim of this study was to investigate the effects of prenatal exposure to EMF on rat myocardium by biochemical and histopathological evaluations. MATERIAL AND METHODS: In this study, 10 pregnant Wistar rats were used. Half of the pregnant rats were exposed to EMF of 3 mT, and the other half to sham conditions during gestation. After parturition, rat pups in the 5 EMF-exposed litters from birth until postnatal day 20 were exposed to EMF of 3 mT for 4 h/day (EMF-exposed group, n = 30). Rat pups in sham litters from birth until postnatal day 20 were exposed to sham conditions (sham group, n= 20). RESULTS: In the EMF-exposed group, lipid peroxidation levels significantly increased compared to sham. Superoxide dismutase activities decreased significantly in the EMF-exposed group compared to sham. TUNEL staining showed that the number of TUNEL-positive cells increased significantly in EMF-exposed rats compared with sham. Under electron microscopy, there were mitochondrial degeneration, reduction in myofibrils, dilated sarcoplasmic reticulum and perinuclear vacuolization in EMF-exposed rats. CONCLUSIONS: In conclusion, the results show that prenatal exposure to EMF causes oxidative stress, apoptosis and morphological pathology in myocardium of rat pups. The results of our study indicate a probable role of free radicals in the adverse effects of prenatal exposure to EMF. Further studies are needed to demonstrate whether the EMF exposure can induce adverse effects on the myocardium.

Effects of human amniotic fluid and membrane in the treatment of Achilles tendon ruptures in locally corticosteroid-induced Achilles tendinosis: an experimental study on rats.

BACKGROUND: To determine the effects of human amniotic fluid and membrane in the treatment of Achilles tendon ruptures, 72 tendons of 36 Wistar rats were injected with betamethasone sodium phosphate. METHODS: By the end of fourth week, both tendons were tenotomized and repaired, then the samples were divided into three groups. The first group was left untreated after suturing. Human amniotic fluid was injected to the second and amniotic fluid and membrane were both administered to the third group. Twenty-four tendons were scored at the end of the first week, and 24 at the end of the second week histopathologically, and 24 biomechanically at the end of the third week. RESULTS: There was a significant statistical difference only between the histopathological results of Groups 2 and 3 at the first week. CONCLUSIONS: Human amniotic membrane and fluid do not add anything to the healing process of Achilles tendon ruptures in the early phase.

A new device to produce a standardized experimental fracture in the rat tibia.

OBJECTIVE: To develop and introduce a new device to produce a standardized closed experimental fracture in the rat tibia. METHODS: This study took place in the Research Laboratory, Medical Faculty, Dokuz Eylul University, in the year 2003. We include 20 healthy male white Wistar rats. After pinning both tibia of the rat intramedullary with the needle of a sterile injector without any incision, we tried to produce a fracture with the pendulum of the device, which was dropped in different angles in 9 rats. The tibial diaphysis of 14 rats in the main study were fractured at 60 degrees. After the fractures were confirmed radiologically, 4 tibia underwent pathological analysis to determine the degree of soft tissue damage and 24 tibia were examined in terms of histological fracture healing. RESULTS: Radiologically, this technique resulted in a transverse or short oblique bicortical fracture in the middle of the tibial diaphysis. The healing process was well adjusted with the classification of Allen. No noticeable soft tissue damage in the fracture region was demonstrated. CONCLUSION: This method of producing an easy and reproducible fracture in a standard fashion without displacement and minimal soft tissue trauma in laboratory animals with this simple apparatus make it a useful technique for bone healing studies.