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1.
The clinical and bacteriologic efficacy of topically applied ciprofloxacin was studied in 60 patients with chronic suppurative otitis media. Two hundred fifty and 125 microg/ml concentrations of ciprofloxacin solutions were given to two groups of patients. The duration of therapy was determined according to the clinical cure at follow-up. More than 21 days of therapy was not needed in any patient. The clinical cure rate with 250 microg/ml ciprofloxacin was 78.1% at 14 days and with 125 microg/ml it was 83.3%. However, a 100% clinical cure rate and complete bacteriologic eradication was obtained in 21 days in both groups. In each group only one patient had otomycosis by the fourteenth day of therapy, although ear discharge had ceased. It was concluded that 125 microg/ml ciprofloxacin could be applied as successfully as 250 microg/ml, and the duration of therapy had to be at least 14 days. This new dosage regimen can be adopted as an optimal dosage for ototopical application of ciprofloxacin in chronic suppurative otitis media. It will also obviously decrease the expense of therapy. 相似文献
2.
Can an electronic portfolio that is both a multimedia container for student work and a tool to support key learning processes have a positive impact on the literacy practices and self-regulated learning skills of students? This article presents the findings of a yearlong study conducted in three Canadian provinces during the 2007–2008 school year initially involving 32 teachers and 388 students. Due to varying levels of implementation our final data set included 14 teachers and 296 students. Using a non-equivalent pre-test/post-test design, we found that grade 4–6 students who were in classrooms where the teacher provided regular and appropriate use of the electronic portfolio tool ePEARL (i.e., medium–high implementation condition, n = 7 classrooms and 121 students), compared to control students (n = 7 classrooms and 175 students) who did not use ePEARL, showed significant improvements (p < .05) in their writing skills on a standardized literacy measure (i.e., the constructed response subtest of the Canadian Achievement Test-4th ed.) and certain metacognitive skills measured via student self-report. The results of this study indicate that teaching with ePEARL has positive impacts on students’ literacy and self-regulated learning skills when the tool is used regularly and integrated into classroom instruction. 相似文献
3.
Bug fixing has a key role in software quality evaluation. Bug fixing starts with the bug localization step, in which developers use textual bug information to find location of source codes which have the bug. Bug localization is a tedious and time consuming process. Information retrieval requires understanding the programme's goal, coding structure, programming logic and the relevant attributes of bug. Information retrieval (IR) based bug localization is a retrieval task, where bug reports and source files represent the queries and documents, respectively. In this paper, we propose BugCatcher, a newly developed bug localization method based on multi‐level re‐ranking IR technique. We evaluate BugCatcher on three open source projects with approximately 3400 bugs. Our experiments show that multi‐level reranking approach to bug localization is promising. Retrieval performance and accuracy of BugCatcher are better than current bug localization tools, and BugCatcher has the best Top N, Mean Average Precision (MAP) and Mean Reciprocal Rank (MRR) values for all datasets. 相似文献
4.
Mustafa Turan Ferhat Gunay Adil Aslan 《Journal of Intelligent and Robotic Systems》2012,65(1-4):73-91
Unmanned Aircraft (UA) have become an integral part of the present-day joint air operations. UA have potential to be employed across the full spectrum of Air Force functions. On the other hand, UA technology could be a subject of an asymmetric use by state actors in high or low density conflict, and/or by non-state actors in many ways including terrorism, drug smuggling, and limited attack with unconventional payloads i.e. biological or chemical agents. Therefore countering the threat associated with the hostile UA use could be necessary in the future. First part of the research revealed that UA can be a threat in the future. In the second part of the research, the SWOT (Strengths-Weaknesses-Opportunities-Threats) analysis supplemented with the Tree analysis (SWOT+Tree) provided a broader look for investigating the factors related to hostile UA use analytically. In literature, there is little information about the concepts for CUAOPS. The final goal of the paper is to find possible solutions and means for a better understanding of the nature of CUAOPS. 相似文献
5.
Ertugrul Yildirim Alper Aslan Ilhan Ozturk 《Renewable & Sustainable Energy Reviews》2012,16(8):6123-6127
The paper investigates the causality relationships among industrial production index, coal consumption and employment in industrial sector for the period of 1973:1–2011:10 in USA. After noticing that there are breaks in the regression model, the Hatemi-J test for cointegration is employed to the cases that take into account two possible regime shifts. It is concluded that there is a long run relationship between industrial production and industrial coal consumption with the breaks at 1983:4 and 1998:4. We found a negative relationship between coal consumption and industrial production for the period of 1973:1–1983:4 and positive relationship for 1983:5–1998:4 period. For the last period that covers 1983:5–2011:10, the cointegration relationship turned to negative. In addition, the results show that causal relationship between coal consumption and industrial production changes over time. 相似文献
6.
Irina V. Nefedova Alexander G. Martynov Alexey A. Averin Gayane A. Kirakosyan Aslan Yu. Tsivadze Yulia G. Gorbunova 《Israel journal of chemistry》2016,56(2-3):181-187
Octopus-like zinc and magnesium phthalocyaninates bearing eight flexible benzylated diethylene glycol chains were synthesized and their interaction with fullerenes C60 and C70 was investigated by UV-Vis spectrophotometric titration, as well as by steady-state and time-resolved fluorescence spectroscopy in chloroform and toluene media. These measurements revealed a high affinity of receptors for C60 and C70, with selectivity to C70: binding constants for C70 are almost two times higher than for C60. These results are interpreted by means of quantum-chemical calculations using the PM6-DH2 Hamiltonian. The binding constants also depend on both the nature of the metal ion in the receptor and the solvent. It is expected that the obtained molecules and supramolecular complexes can be used for further elaboration of optoelectronic donor-acceptor materials. 相似文献
7.
8.
Mustafa Aslan 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(14):2072-2078
Hydrogen gas is an ideal alternative fuel and produces no greenhouse gases. The dark fermentation is considered the most attractive for production of biohydrogen gas. Duckweed is an aquatic plant that has treatment properties and can be used as biomass for the fermentation to produce eventually bio-hydrogen production. This study investigated the impact of different temperature, pH, and substrate concentration on bio-hydrogen production by fermentation. Experimental tests were run flask studies in serum bottles by aim of determing the optimal operating conditions to maximize bio-hydrogen production. According to the results, concentration loading in the range 30–40 g DW/L was determined as suitable for efficient bio-hydrogen production. Different temperatures on bio-hydrogen production were compared, and 35°C was observed to be more effective than others. Moreover, pH 5.5 was determined as the optimal pH value. 相似文献
9.
Mustafa Aslan Gary Chinga-Carrasco Bent F. S?rensen Bo Madsen 《Journal of Materials Science》2011,46(19):6344-6354
Due to the typical large variability in the measured mechanical properties of flax fibres, they are often employed only in
low grade composite applications. The present study aims to investigate the reasons for the variability in tensile properties
of flax fibres. It is found that an inaccuracy in the determination of the cross-sectional area of the fibres is one major
reason for the variability in properties. By applying a typical circular fibre area assumption, a considerable error is introduced
into the calculated mechanical properties. Experimental data, together with a simple analytical model, are presented to show
that the error is increased when the aspect ratio of the fibre cross-sectional shape is increased. A variability in properties
due to the flax fibres themselves is found to originate from the distribution of defects along the fibres. Two distinctive
types of stress–strain behaviours (linear and nonlinear) of the fibres are found to be correlated with the amount of defects.
The linear stress–strain curves tend to show a higher tensile strength, a higher Young’s modulus, and a lower strain to failure
than the nonlinear curves. Finally, the fibres are found to fracture by a complex microscale failure mechanism. Large fracture
zones are governed by both surface and internal defects; and these cause cracks to propagate in the transverse and longitudinal
directions. 相似文献
10.
A promising line of research for radar systems attempts to optimize the detector thresholds so as to maximize the overall performance of a radar detector–tracker pair. In the present work, we attempt to move in a direction to fulfill this promise by considering a particular dynamic optimization scheme which relies on a non-simulation performance prediction (NSPP) methodology for the probabilistic data association filter (PDAF), namely, the modified Riccati equation (MRE). By using a suitable functional approximation, we propose a closed-form solution for the special case of a Neyman–Pearson (NP) detector. The proposed solution replaces previously proposed iterative solution formulations and results in dramatic improvement in computational complexity without sacrificed system performance. Moreover, it provides a theoretical lower bound on the detection signal-to-noise ratio (SNR) concerning when the whole tracking system should be switched to the track before detect (TBD) mode. 相似文献