4,952 research outputs found
Evaluation of an In-service Training Program for Primary-school Language Teachers in Turkey
Despite the critical importance of in-service education programs (INSETs) for teachers’ on-going professional development, educators often report problems concerning many INSETs. However, due to lack of systematic evaluation studies of INSETs in especially language education field, specific problems in these courses cannot be diagnosed, and they are left unresolved. The present study, therefore, evaluates a one-week INSET offered by the Turkish Ministry of Education to explore its sustained impact on language teachers’ attitudes, knowledge-base, and classroom practices. The program is first evaluated against the criteria for effective INSETs suggested by previous literature. Then, data are gathered through course materials analysis, interviews with trainers and teachers, and through a questionnaire distributed to 72 teachers 18 months after the course ended. Findings indicate that although the teachers’ attitudes are positive towards the course in general, the program has limitations especially in terms of its planning and evaluation phases, and its impact on teachers’ practices. Implications for future INSETs will be provided based on the findings
Regression on feature projections
Cataloged from PDF version of article.This paper describes a machine learning method, called Regression on Feature Projections (RFP), for predicting a real-valued target
feature, given the values of multiple predictive features. In RFP training is based on simply storing the projections of the training instances on
each feature separately. Prediction of the target value for a query point is obtained through two averaging procedures executed sequentially.
The ®rst averaging process is to ®nd the individual predictions of features by using the K-Nearest Neighbor (KNN) algorithm. The second
averaging process combines the predictions of all features. During the ®rst averaging step, each feature is associated with a weight in order to
determine the prediction ability of the feature at the local query point. The weights, found for each local query point, are used in the second
prediction step and enforce the method to have an adaptive or context-sensitive nature. We have compared RFP with KNN and the rule
based-regression algorithms. Results on real data sets show that RFP achieves better or comparable accuracy and is faster than both KNN and
Rule-based regression algorithms. (C)2000 Elsevier Science B.V. All rights reserved
A Retrospective Evaluation of Crown-fractured Permanent Teeth Treated in a Pediatric Dentistry Clinic
A retrospective study was carried out on the dental trauma records of 93 patients (55 boys, 38 girls) with 129 crown-fractured teeth. The patients’ average age was 9.57 years (SD 1.57), ranging between 7 and 15 years. Uncomplicated crown facture (comprising enamel–dentin) was the most observed type of injury (n = 107, 83%). Only 15 patients (16.13%) sought treatment in less than 24 h following the injury. Of 41 injured teeth (31.79%) the apices were open at the time of presentation at the clinic. The initial treatment of these injured teeth were interim restoration with acid-etch and composite (69%), Cvek amputation (2.33%), fragment reattachment (1.55%), apexification (APX, 10.07%), and root-canal treatment (RCT, 17.05%). Out of 94 teeth, which were diagnosed as vital on admittance, 23 (24.46%) later developed pulp necrosis and required APX or RCT depending on their apical status. In 66 teeth (51.16%) definitive treatment was provided with only esthetic restoration (ER), while in 15.50% and 26.68% of injured teeth ER was carried out following APX and RCT, and RCT, respectively. Definitive treatment was provided in 3–6 months for 29.45% of the injured teeth, while 27.13% and 20.16% of teeth received definitive treatment within 1–3 months and 6 months to 1 year, respectively. Type of crown-fracture, elapsed time following injury, and vitality of the tooth on admittance and pulp necrosis observed were significantly related to the total time spent for definitive treatment (P \u3c 0.05)
Eruption Delay and Sequelae in Permanent Incisors Following Intrusive Luxation in Primary Dentition: A Case Report
With respect to its consequences, intrusive luxation is one of the most severe form of dental traumatic injuries in primary dentition. This case report presents crown and root deformation of a permanent incisor together with its delayed eruption which have resulted from a traumatic injury to its predecessor
MIMO free-space optical communication employing subcarrier intensity modulation in atmospheric turbulence channels
In this paper, we analyse the error performance of transmitter/receiver array free-space optical (FSO) communication system employing binary phase shift keying (BPSK) subcarrier intensity modulation (SIM) in clear but turbulent atmospheric channel. Subcarrier modulation is employed to eliminate the need for adaptive threshold detector. Direct detection is employed at the receiver and each subcarrier is subsequently demodulated coherently. The effect of irradiance fading is mitigated with an array of lasers and photodetectors. The received signals are linearly combined using the optimal maximum ratio combining (MRC), the equal gain combining (EGC) and the selection combining (SelC). The bit error rate (BER) equations are derived considering additive white Gaussian noise and log normal intensity fluctuations. This work is part of the EU COST actions and EU projects
First report of Barley Yellow Dwarf Viruses (BYDVs) on dicotyledonous weed hosts in Turkey
Yellow dwarf viruses (YDVs) are economically destructive viral diseases of cereal crops, which cause the reduction of harvested yield and quality of grains. Up to now the identification of such viruses was limited to monocotyledonous Poaceae weed hosts, and was not investigated in dicotyledons. In this study, using DAS-ELISA and RT-PCR methods, 6 dicotyledonous weed species, collected from Trakya, Turkey, were examined for the presence of the YDVs pathogens BYDV-PAV, BYDV-MAV, BYDV-RMV, BYDV-SGV and CYDV-RPV. The screening tests revealed certain samples of Geranium dissectum L. and Juncus compressus Jacq. were infected with BYDV-PAV, while other samples of the same species were positive for BYDV-MAV. Additionally, RT-PCR tests of both weed species revealed cases of mixed infection by BYDV-PAV and BYDV-MAV. Transmission experiments using the aphid species Rhopalosiphum padi L. showed that BYDV-PAV was transmitted persistently from Geranium dissectum to barley cv. Barbaros seedlings. To our knowledge, this is the first report of Geranium dissectum and Juncus compressus as possible plant hosts of BYDV-PAV and BYDV-MAV in Turkey
Comparison of the temporal properties of medium latency responses induced by cortical and peripheral stimulation
Sudden foot dorsiflexion lengthens soleus muscle and activates stretch-based spinal reflexes. Dorsiflexion can be triggered by activating tibialis anterior (TA) muscle through peroneal nerve stimulation or transcranial magnetic stimulation (TMS) which evokes a response in the soleus muscle referred to as Medium Latency Reflex (MLR) or motor-evoked potential-80 (Soleus MEP80), respectively. This study aimed to examine the relationship between these responses in humans. Therefore, latency characteristics and correlation of responses between soleus MEP80 and MLR were investigated. We have also calculated the latencies from the onset of tibialis activity, i.e., subtracting of TA-MEP from MEP80 and TA direct motor response from MLR. We referred to these calculations as Stretch Loop Latency Central (SLLc) for MEP80 and Stretch Loop Latency Peripheral (SLLp) for MLR. The latency of SLLc was found to be 61.4 ± 5.6 ms which was significantly shorter (P = 0.0259) than SLLp (64.0 ± 4.2 ms) and these latencies were correlated (P = 0.0045, r = 0.689). The latency of both responses was also found to be inversely related to the response amplitude (P = 0.0121, r = 0.451) probably due to the activation of large motor units. When amplitude differences were corrected, i.e. investigating the responses with similar amplitudes, SLLp, and SLLc latencies found to be similar (P = 0.1317). Due to the identical features of the soleus MEP80 and MLR, we propose that they may both have spinal origins
Primary Molar Pulpotomies with Different Hemorrhage Control Agents and Base Materials: A Randomized Clinical Trial
Objective: To evaluate the clinical and radiographical success of primary molar pulpotomies which used 15.5% ferric sulfate (FS) or 1.25% sodium hypochlorite (NaOCl) for hemostasis and zinc oxide-eugenol (ZOE) and calcium hydroxide (CH) pastes as base materials.
Methods: In 29 healthy children, 80 primary molars were randomly allocated to one of the study groups: Group 1: FS-ZOE, Group 2: FS-CH, Group 3: NaOCl-ZOE, and Group 4: NaOCl-CH. After hemostasis with the respective solutions, pulp stumps and floor of the pulp chambers were covered with either ZOE or CH pastes. All teeth were restored with stainless steel crowns. Follow-up examinations were carried out at 1, 3, 6, and 12 months.
Results: One tooth in Group 1 and two teeth in Group 4 were extracted because of pain and periapial pathosis at sixth month. After 12 months, clinical success rates of pulpotomies in Groups 1-4 were 95%, 100%, 100%, and 89.5%, respectively. The differences were not significant (P = 0.548). Radiographic success rates for Groups 1-4 were 80%, 88.9%, 78.9%, and 84.2%, respectively. No statistically significant difference was found (P = 0.968). Pain on percussion was the most observed clinical finding. However, internal root resorption was the most common radiological finding and it was observed significantly more in mandibular primary molars (P \u3c 0.05).
Conclusion: Both ZOE and CH can be preferred as base materials after hemostasis achieved by the use of 15.5% FS or 1.25% NaOCl in primary tooth pulpotomy
Impact of receive diversity on the performance of amplify-and-forward relaying under APS and IPS power constraints
Laminar Forced Convection and Entropy Generation of ZnO-Ethylene Glycol Nanofluid Flow through Square Microchannel with using Two-Phase Eulerian-Eulerian Model
In this paper, convective heat transfer and entropy generation of ZnO-EG nanofluid flow through a square microchannel are numerically investigated. Flow is modelled by using Eulerian-Eulerian two phase flow model. Nanoparticle volume fraction of ZnO-EG nanofluid ranged between %1.0 and %4.0. As a result, it is found that the convective heat transfer coefficient of flow increased from 9718.15 W/m2K to 23010.79 W/m2K when 4.0% ZnO nanoparticle addition to pure EG at Re=100. Total entropy generation of ZnO-EG nanofluid decreases with increase in nanoparticle volume fraction of ZnO-EG nanofluid. It is also observed that the Bejan number decreases with increase in nanoparticle volume fraction of ZnO-EG nanofluid
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