63 research outputs found

    Determining of the University Freshmen Students’ Misconceptions and Alternative Conceptions about Mitosis and Meiosis

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    AbstractThe purpose of our study is to determine the misconceptions and inadequate information which the university freshmen students’ held about mitosis and meiosis. We majored mostly on the numbers of chromosome potential and the DNA amount in our questions. In addition we wanted our students to interpret their past information about the subject. The results of our qualitative analyses show that students reword interphase as preparatory period but they don’t recognize what happens in this period, precisely. Also, they don’t explain DNA, chromosome and gene concepts. And they don’t precisely recognize the importance of mitosis and meiosis for life

    Identifiying and Comparing the Degree of Difficulties Biology Subjects by Adjusting it is Reasons in Elemantary and Secondary Education

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    AbstractThe purpose of this study was to determine elementary school eighth grade students’ and secondary school 12th grade students’ perceptions of having difficulties with respect to understanding Biology subjects, and whether they still had difficulties in this hardly learnt subjects when they came to high school after the elementary school. The results revealed that “Controller and Organizer Systems”, a biology subject in elementary school and “Photosyntesis”, a biology subject at secondary school in Turkey were more difficult to understand than other biology subjects for the participants in our study

    T2\mathbb{T}^{2}- inflation: Sourced by energy-momentum squared gravity

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    In this paper, we examine chaotic inflation within the context of the energy-momentum squared gravity (EMSG) focusing on the energy-momentum powered gravity (EMPG) that incorporates the functional f(T2)∝(T2)βf(\mathbb{T}^2)\propto (\mathbb{T}^2)^{\beta} in the Einstein-Hilbert action, in which β\beta is a constant and T2≡TμνTμν\mathbb{T}^2\equiv T_{\mu \nu}T^{\mu \nu} where TμνT_{\mu \nu} is the energy-momentum tensor, which we consider to represent a single scalar field with a power-law potential. We demonstrate that the presence of EMSG terms allows the single-field monomial chaotic inflationary models to fall within current observational constraints, which are otherwise disfavored by Planck and BICEP/Keck findings. We show that the use of a non-canonical Lagrangian with chaotic potential in EMSG can lead to significantly larger values of the non-Gaussianity parameter, fNlequif_{\rm Nl}^{\rm equi} whereas EMSG framework with canonical Lagrangian gives rise to results similar to those of the standard single-field model.Comment: 25 pages, 4 figures, and 2 tables, added discussion, accepted by Physics of the Dark Univers

    ANTINEPHROLITHIATIC ACTIVITY OF PERSEA AMERICANA (AVOCADO) AND VIBURNUM OPULUS (GUELDER ROSE) AGAINST ETHYLENE GLYCOL-INDUCED NEPHROLITHIASIS IN RATS

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    Background: Nephrolithiasis is a severe health problem causing morbidity. Chemolisis, extracorporeal shock wave lithotripsy (SWL), percutaneous nephrolithotomy (PNL), retrograde ureterorenoscopy (URS), and open and laparoscopic surgery are used for treatment with various success rates. Medical treatments with fewer complications were investigated thoroughly. Materials and Methods: In this study, we evaluated the effects of Persea americana (avocado) leaves and Viburnum opulus (guelder rose) fruits on nephrolithiasis in an animal model and used 42 rats. The groups received both low and high doses of Persea americana leaves and Viburnum opulus fruit ethanol extracts orally for 28 days. These two plants have been used for years in Turkey for their nephrolithiatic effect. Results: Avocado and guelder rose increased the urine volume and urine citrate levels, decreased urine cystine and oxalate levels, and lowered the crystal deposits in kidney tissue. Avocado and guelder rose also prevented oxidant damage and crystal formation in kidney tissue samples. Conclusion: The two plants that have been used for years for nephrolithiasis treatment in Turkey can safely be used for kidney stones

    Comparison of different bronchial closure techniques following pneumonectomy in dogs

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    The comparison of the histologic healing and bronchopleural fistula (BPF) complications encountered with three different BS closure techniques (manual suture, stapler and manual suture plus tissue flab) after pneumonectomy in dogs was investigated for a one-month period. The dogs were separated into two groups: group I (GI) (n = 9) and group II (GII) (n = 9). Right and left pneumonectomies were performed on the animals in GI and GII, respectively. Each group was further divided into three subgroups according to BS closure technique: subgroup I (SGI) (n = 3), manual suture; subgroup II (SGII) (n = 3), stapler; and subgroup III (SGIII) (n = 3), manual suture plus tissue flab. The dogs were sacrificed after one month of observation, and the bronchial stumps were removed for histological examination. The complications observed during a one-month period following pneumonectomy in nine dogs (n = 9) were: BPF (n = 5), peri-operative cardiac arrest (n = 1), post-operative respiratory arrest (n = 1), post-operative cardiac failure (n = 1) and cardio-pulmonary failure (n = 1). Histological healing was classified as complete or incomplete healing. Histological healing and BPF complications in the subgroups were analyzed statistically. There was no significant difference in histological healing between SGI and SGIII (p = 1.00; p > 0.05), nor between SGII and SGIII (p = 1.00; p > 0.05). Similarly, no significant difference was observed between the subgroups in terms of BPF (p = 0.945; p > 0.05). The results of the statistical analysis indicated that manual suture, stapler or manual suture plus tissue flab could be alternative methods for BS closure following pneumonectomy in dogs

    Mosaic: A Satellite Constellation to Enable Groundbreaking Mars Climate System Science and Prepare for Human Exploration

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    The Martian climate system has been revealed to rival the complexity of Earth\u27s. Over the last 20 yr, a fragmented and incomplete picture has emerged of its structure and variability; we remain largely ignorant of many of the physical processes driving matter and energy flow between and within Mars\u27 diverse climate domains. Mars Orbiters for Surface, Atmosphere, and Ionosphere Connections (MOSAIC) is a constellation of ten platforms focused on understanding these climate connections, with orbits and instruments tailored to observe the Martian climate system from three complementary perspectives. First, low-circular near-polar Sun-synchronous orbits (a large mothership and three smallsats spaced in local time) enable vertical profiling of wind, aerosols, water, and temperature, as well as mapping of surface and subsurface ice. Second, elliptical orbits sampling all of Mars\u27 plasma regions enable multipoint measurements necessary to understand mass/energy transport and ion-driven escape, also enabling, with the polar orbiters, dense radio occultation coverage. Last, longitudinally spaced areostationary orbits enable synoptic views of the lower atmosphere necessary to understand global and mesoscale dynamics, global views of the hydrogen and oxygen exospheres, and upstream measurements of space weather conditions. MOSAIC will characterize climate system variability diurnally and seasonally, on meso-, regional, and global scales, targeting the shallow subsurface all the way out to the solar wind, making many first-of-their-kind measurements. Importantly, these measurements will also prepare for human exploration and habitation of Mars by providing water resource prospecting, operational forecasting of dust and radiation hazards, and ionospheric communication/positioning disruptions

    Femoral lengthening and deformity correction using the Fitbone motorized lengthening nail

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    WOS: 000348307300019PubMed ID: 25326815This study reports our results with retrograde Fitbone insertion in patients with femoral shortening and deformity. We also present our experience regarding the benefits, complications, and factors associated with complications of the Fitbone technique. Twelve males and ten females had femoral shortening and deformities treated using the retrograde Fitbone technique between 2009 and 2012. The etiologies were post-traumatic in 12 patients, poliomyelitis in four, cosmetic in two, congenital hypoplasia in two, achondroplasia in one, and Perthes sequela in one. The follow-up time was 30.8 months. The mean lengthening was 5.8 (range 2-14) cm. The degree of acute angular correction was 9A degrees (5-22A degrees) in nine cases. The time to full weight-bearing was 5.9 months. The consolidation index was 1.07 (0.75-1.62) months/cm. Complete consolidation was obtained in all cases except two. Running back was observed in two cases. The Fitbone technique allows accurate deformity correction. The rigid reamers allow the surgeon to use the Fitbone even in patients with a narrow medullary canal. As this might result in poor bone regeneration, thinner lengthening nails should be considered

    Our Septoplasty Results: Evaluation with the Nose Scale

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    Objective: The aim of this study was to evaluate the effectiveness of septoplasty and septoplasty + bilateral radio frequency ablation of inferior turbinate (b-RFAIT) according to the type of operation, age groups, gender of patients, and the duration of control period by using Nasal Obstruction Symptom Evaluation (NOSE) Scale. Materials and Methods: Prospective observational study was undertaken in the otolaryngology department of a training hospital. Using the NOSE scale, the study prospectively compared the results of septoplasty only and septoplasty with b-RFAIT in the treatment of nasal obstruction caused by the combination of septal deviation and turbinate hypertrophy. Patients were divided into 2 groups. The first group had only septoplasty and the second group had septoplasty with b-RFAIT. General and local anesthesia were applied in both groups. To review clinical success, all patients were controlled at the 1st week, 1st month, and 3rd month. Results: One hundred seventy-eight adult patients (male/female: 127/51) with chronic nasal obstruction complaint were enrolled in this prospective study. Our data demonstrated significant improvement from baseline after 24 months for the NOSE scores in both the septoplasty and septoplasty + b-RFAIT groups. No statistical difference was noted in the amount of postoperative improvement between the 2 treatment groups (P = 0.306). No significant difference was observed between general and local anesthesia with respect to patients'(TM) preop and postop mean scores (P > 0.05). There was a significant difference between the age of patients'(TM) postoperative mean (P < 0.001). There were 4 postoperative means with respect to control time. There was an 82.29% decrease in the complaints of patients at 0 to 6 months, 80.51% decrease at 7 to 12 months, 76.1% decrease at 13 to 18 months, and 59.67% decrease at 19 to 24 months. Only the last group had a significant difference regarding mean change in scores (P < 0.001). Conclusions: This study shows that septoplasty + bilateral turbinate radiofrequency should be applied to patients who suffer from septum deviation with concha hypertrophy. Postoperative NOSE scale shows that the success of operation does not depend on the gender of patients and operation types (general or local anesthesia). We conclude that younger patients (18-40 age) who have obstruction with septal deviation and septum deviation with concha hypertrophy benefit more from operation than older patients do
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