How About the Real Responders\u27 Perceptions? A Comparative Case Study on School Principals\u27 Perceptions of School Administration Through Metaphors in USA and Turkey

Expectations of school administration changed dramatically over the course of the 20th century. Today, the roles and responsibilities of school administrators must be re-defined for success in the 21st century. The current research aimed at revealing the perception of school leadership by school administrators who were expected to cope with problems and enable students to succeed in the U.S. and Turkey. Comparative case study design was used to analyze and compare the U.S. and Turkey school administrators’ perceptions of school leadership through metaphors. The study sample consisted of 47 school administrators employed in K-12 schools in Turkey and the U.S. The data collection tool was a semi-structured interview form. Data obtained were analyzed through content analysis. As a result, 47 participants defined school administration through 43 different metaphors. Participants used 23 positive, 13 negative, and 11 neutral metaphors to define school administration. Within these three categories, five themes emerged: porter (13 metaphors), firefighter (11 metaphors), father (10 metaphors), captain (7 metaphors), and maestro (6 metaphors). Although participants from two countries used mostly different metaphors, school administration was perceived similarly in Turkey and the US. This showed that in both countries, school administrators take on similar responsibilities and roles. The most distinct difference between the school administrators in the two countries was that school administrators from Turkey more unfavorably approach the job they take on, while school administrators from the U.S. defined their job as being more complicated

Effects of dietary supplementation of L-carnitine on performance, carcass and meat characteristics of quails

The present study was conducted to determine the effects of feeding diets containing two levels of metabolizable energy (12.13 or 11.72 MJ ME/kg) and two different fat sources (sunflower- and fish-oil) with or without supplemental L-carnitine (0 or 50 mg/kg diet) on growth performance and carcass and meat characteristics of Japanese quails. Two hundred and forty day-old male quail chicks were randomly assigned to eight treatment groups, each subdivided into three replicates of 10 chicks. The chicks were raised from hatch until 5 wks of age. Feeding the diet containing 12.13 MJ ME/kg increases body weight and body weight gain significantly, and improved the feed conversion ratio above that of the lower energy diet. Feed intakes of the birds were unaffected by treatments. The cold carcass yield of quails fed the diet containing sunflower oil was significantly higher than those receiving the diets containing fish oil. After 35 days of feeding the diet containing the standard energy level (12.13 MJ ME/kg) the thigh yield of the birds was significantly higher than that of the chicks on the lower energy diet. Dietary treatments did not affect pH values of edible meat in the quails. Feeding diets containing sunflower oil and L-carnitine significantly decreased malonaldehyde (MA) amounts in the edible meat. The crude protein content of the edible meat fraction was significantly higher when the dietary energy level was decreased from 12.13 to 11.72 MJ ME/kg diet. Decreasing dietary energy levels significantly decreased the “L” (lightness) and “b” values (less yellow) of the meat, while dietary L-carnitine supplementation resulted in a significant increase in “L” value. The total edible meat of the quails on the diets containing fish oil had a higher “a” value (more red) than the quails receiving sunflower oil in their diets. It was concluded that additional studies are required to clarify the role of dietary L-carnitine in the oxidation of long-chain fatty acids, its antioxidant properties and its importance in energy metabolism in Japanese quails. Keywords: L-carnitine; metabolizable energy; fat sources; carcass quality; shelflife of edible meat South African Journal of Animal Science Vol. 37 (3) 2007: pp.189-20

Absolute dimensions of eclipsing binaries. XXVIII. BK Pegasi and other F-type binaries: Prospects for calibration of convective core overshoot

We present a detailed study of the F-type detached eclipsing binary BK Peg, based on new photometric and spectroscopic observations. The two components, which have evolved to the upper half of the main-sequence band, are quite different with masses and radii of (1.414 +/- 0.007 Msun, 1.988 +/- 0.008 Rsun) and (1.257 +/- 0.005 Msun, 1.474 +/- 0.017 Rsun), respectively. The 5.49 day period orbit of BK Peg is slightly eccentric (e = 0.053). The measured rotational velocities are 16.6 +/- 0.2 (primary) and 13.4 +/- 0.2 (secondary) km/s. For the secondary component this corresponds to (pseudo)synchronous rotation, whereas the primary component seems to rotate at a slightly lower rate. We derive an iron abundance of [Fe/H] =-0.12 +/- 0.07 and similar abundances for Si, Ca, Sc, Ti, Cr and Ni. Yonsei-Yale and Victoria-Regina evolutionary models for the observed metal abundance reproduce BK Peg at ages of 2.75 and 2.50 Gyr, respectively, but tend to predict a lower age for the more massive primary component than for the secondary. We find the same age trend for three other upper main-sequence systems in a sample of well studied eclipsing binaries with components in the 1.15-1.70 Msun range, where convective core overshoot is gradually ramped up in the models. We also find that the Yonsei-Yale models systematically predict higher ages than the Victoria-Regina models. The sample includes BW Aqr, and as a supplement we have determined a [Fe/H] abundance of -0.07 +/- 0.11 for this late F-type binary. We propose to use BK Peg, BW Aqr, and other well-studied 1.15-1.70 Msun eclipsing binaries to fine-tune convective core overshoot, diffusion, and possibly other ingredients of modern theoretical evolutionary models.Comment: Accepted for publication in Astronomy and Astrophysic

MnOx-Promoted PdAg Alloy Nanoparticles for the Additive-Free Dehydrogenation of Formic Acid at Room Temperature

Formic acid (HCOOH) has a great potential as a safe and a convenient hydrogen carrier for fuel cell applications. However, efficient and CO-free hydrogen production through the decomposition of formic acid at low temperatures (<363 K) in the absence of additives constitutes a major challenge. Herein, we present a new heterogeneous catalyst system composed of bimetallic PdAg alloy and MnOx nanoparticles supported on amine-grafted silica facilitating the liberation of hydrogen at room temperature through the dehydrogenation of formic acid in the absence of any additives with remarkable activity (330 mol H2·mol catalyst-1·h-1) and selectivity (>99%) at complete conversion (>99%). Moreover this new catalytic system enables facile catalyst recovery and very high stability against agglomeration, leaching, and CO poisoning. Through a comprehensive set of structural and functional characterization experiments, mechanistic origins of the unusually high catalytic activity, selectivity, and stability of this unique catalytic system are elucidated. Current heterogeneous catalytic architecture presents itself as an excellent contender for clean hydrogen production via room-temperature additive-free dehydrogenation of formic acid for on-board hydrogen fuel cell applications. © 2015 American Chemical Society

Transumbilical Totally Laparoscopic Single-Port Nissen Fundoplication: A New Method of Liver Retraction: The Istanbul Technique

Mustafa Kemal Ataturk, founder of the Turkish Republic, had guarded many German scientists of a Jewish descent before the Second World War. Dr. Rudolf Nissen was one of the outstanding surgeons who had served in the Turkish university hospitals. He had created an antireflux procedure which is named after his own name while he was working in our clinic, the CerrahpaAYa Hospital. From a laparoscopic approach, the Nissen fundoplication was the gold standard intervention for the surgical treatment of gastroesophageal reflux disease (GERD). Currently, video laparoscopic surgery is evolving quickly with the guidance of new technology. Single-port (SP) laparoscopic transumbilical surgery is one of the newest branches of advanced laparoscopy

Intracellular modulation of excited-state dynamics in a chromophore dyad: Differential enhancement of photocytotoxicity targeting cancer cells

The photosensitized generation of reactive oxygen species, and particularly of singlet oxygen [O2(a1Δg)], is the essence of photodynamic action exploited in photodynamic therapy. The ability to switch singlet oxygen generation on/off would be highly valuable, especially when it is linked to a cancer-related cellular parameter. Building on recent findings related to intersystem crossing efficiency, we designed a dimeric BODIPY dye with reduced symmetry, which is ineffective as a photosensitizer unless it is activated by a reaction with intracellular glutathione (GSH). The reaction alters the properties of both the ground and excited states, consequently enabling the efficient generation of singlet oxygen. Remarkably, the designed photosensitizer can discriminate between different concentrations of GSH in normal and cancer cells and thus remains inefficient as a photosensitizer inside a normal cell while being transformed into a lethal singlet oxygen source in cancer cells. This is the first demonstration of such a difference in the intracellular activity of a photosensitizer. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Increased Risk of Vascular Events in Emergency Room Patients Discharged Home with Diagnosis of Dizziness or Vertigo: A 3-Year Follow-Up Study

BACKGROUND: Dizziness and vertigo symptoms are commonly seen in emergency room (ER). However, these patients are often discharged without a definite diagnosis. Conflicting data regarding the vascular event risk among the dizziness or vertigo patients have been reported. This study aims to determine the risk of developing stroke or cardiovascular events in ER patients discharged home with a diagnosis of dizziness or vertigo. METHODOLOGY: A total of 25,757 subjects with at least one ER visit in 2004 were identified. Of those, 1,118 patients were discharged home with a diagnosis of vertigo or dizziness. A Cox proportional hazard model was performed to compare the three-year vascular event-free survival rates between the dizziness/vertigo patients and those without dizziness/vertigo after adjusting for confounding and risk factors. RESULTS: We identified 52 (4.7%) vascular events in patients with dizziness/vertigo and 454 (1.8%) vascular events in patients without dizziness/vertigo. ER patients discharged home with a diagnosis of vertigo or dizziness had 2-fold (95% confidence interval [CI], 1.35-2.96; p<0.001) higher risk of stroke or cardiovascular events after adjusting for patient characteristics, co-morbidities, urbanization level of residence, individual socio-economic status, and initially taking medications after the onset of dizziness or vertigo during the first year. CONCLUSIONS: ER patients discharged home with a diagnosis of dizziness or vertigo were at a increased risk of developing subsequent vascular events than those without dizziness/vertigo after the onset of dizziness or vertigo. Further studies are warranted for developing better diagnostic and follow-up strategies in increased risk patients

Recent Advancements in the LC- and GC-Based Analysis of Malondialdehyde (MDA): A Brief Overview

Malondialdehyde (MDA) is an end-product of lipid peroxidation and a side product of thromboxane A2 synthesis. Moreover, it is not only a frequently measured biomarker of oxidative stress, but its high reactivity and toxicity underline the fact that this molecule is more than “just” a biomarker. Additionally, MDA was proven to be a mutagenic substance. Having said this, it is evident that there is a major interest in the highly selective and sensitive analysis of this molecule in various matrices. In this review, we will provide a brief overview of the most recent developments and techniques for the liquid chromatography (LC) and gas chromatography (GC)-based analysis of MDA in different matrices. While the 2-thiobarbituric acid assay still is the most prominent methodology for determining MDA, several advanced techniques have evolved, including GC–MS(MS), LC–MS(MS) as well as several derivatization-based strategies