Abundance analyses of helium-rich subluminous B stars

The connection between helium-rich hot subdwarfs of spectral types O and B (He-sdB) has been relatively unexplored since the latter were found in significant numbers in the 1980's. In order to explore this connection further, we have analysed the surface composition of six He-sdB stars, including LB 1766, LB 3229, SB 21 (= Ton-S 137 = BPS 29503-0009), BPS 22940-0009, BPS 29496-0010, and BPS 22956-0094. Opacity-sampled line-blanketed model atmospheres have been used to derive atmospheric properties and elemental abundances. All the stars are moderately metal-poor compared with the Sun ([Fe/H] ~ -0.5). Four stars are nitrogen-rich, two of these are carbon-rich, and at least four appear to be neon-rich. The data are insufficient to rule out binarity in any of the sample. The surface composition and locus of the N-rich He-sdBs are currently best explained by the merger of two helium white dwarfs, or possibly by the merger of a helium white dwarf with a post-sdB white dwarf. C-rich He-sdBs require further investigation.Comment: Accepted 2010 July

Preconditioning and Dynamic Stimuli

Westerhoff, H.V. [Promotor]Plant, N.J. [Copromotor

Anomalous organic magnetoresistance from competing carrier-spin-dependent interactions with localized electronic and nuclear spins

We describe a new regime for low-field magnetoresistance in organic semiconductors, in which the spin-relaxing effects of localized nuclear spins and electronic spins interfere. The regime is studied by the controlled addition of localized electronic spins to a material that exhibits substantial room-temperature magnetoresistance ($\sim 20$\%). Although initially the magnetoresistance is suppressed by the doping, at intermediate doping there is a regime where the magnetoresistance is insensitive to the doping level. For much greater doping concentrations the magnetoresistance is fully suppressed. The behavior is described within a theoretical model describing the effect of carrier spin dynamics on the current

An Industrial Heritage Case Study in Ayvalık: Ertem Olive Oil Factory

Ayvalık is a pioneer settlement in the West Anatolia with an olive-based industry since its establishment. However, due to fast technological developments and changes in production systems, there is a large stock of derelict industrial buildings within the city center. In addition, few of them are restored under poor conditions as a result of financial profits. This situation puts Ayvalık’s olive industrial heritage which constitutes the identity of the town at critical risk of extinction. Ertem Olive Oil Factory is one of the industrial heritage buildings in Ayvalık dating back to 1910 which is a typical well preserved-medium scale 19th-century olive oil factory including both olive oil and soap productions. The aim of this paper is to discuss a conservation approach for the industrial settlement of Ayvalık by assessing the factory and its close environment through values, problems and potentials. The paper thus begins with brief history of Ayvalık and the effects of industrialization on the city. It continues with theoretical principles of adaptive re-use through contemporary literature and general evaluation of adaptive re-use examples in Ayvalık according to these principles. The third part focuses on the general characteristics of Ertem Olive Oil Factory and its close environment. The final part discusses the conservation approach for the adaptive re-use through values, problems and potentials of the building and Ayvalık

Fungal contaminants observed during micropropagation of Lilium candidum L. and the effect of chemotherapeutic substances applied after sterilization

Lilium candidum L. is a species which grows in the South West Anatolia region of Turkey. It is a bulbous plant with beautifully scented flowers and is used in the floral industry. The bulbs are produced by using traditional propagation and in vitro techniques. Micropropagation is a rapid propagation technique, but the greatest problem is contamination with fungi and bacteria. Antibiotic and fungicide treatments were done after sterilization for micropropagation of L. candidum. Fungal contaminants formed during the culture were determined. Bulb scales were used as explants (5 - 10 mm width) and were cultured in photoperiodic conditions (16 h light, 8 h dark) or complete darkness. Bulb scales rinsed in water were surface sterilized, then solutions containing chemotherapeutic substances (Benomyl, Nystatin, Streptomycin, Penicillin) in different combinations were applied for 30 min and subsequently were cultured in MS medium with supplement 0.1 mg dm-3 NAA + 0.01 mg dm-3 BA. During the experiment, fungal contaminants were observed in full treatments. Determined contaminants were identified according to their morphological and cultural characteristics by cultivation and were comprised of: Fusarium, Penicillium, Alternaria, Rhizopus, Cylindrocarpon and Aspergillus species. The most effective treatment against fungal contaminations was achieved by utilizing a Benomyl (100 mg dm-3) + Nystatin (100 mg dm-3) treatment combination

Day of the week effect on foreign exchange market volatility: Evidence from Turkey

Cataloged from PDF version of article.This paper assesses the day of the week effect of the daily depreciation of the Turkish lira (TL) against the US dollar (USD) and its volatility. The empirical evidence from Turkey presented here suggests that Thursdays are associated with higher and Mondays with lower depreciation rates compared to those of Wednesdays. Moreover, Mondays and Tuesdays are associated with higher volatility than Wednesdays. © 2006 Elsevier B.V. All rights reserved

Exploring the sociotropy-autonomy dimensions in a sample of Turkish psychiatric inpatients

The present study explored the constructs of sociotropy and autonomy with a group of Turkish depressed inpatients, who were administered the Beck Depression Inventory, the Dysfunctional Attitudes Scale, the Automatic Thoughts Questionnaire, and the Sociotropy-Autonomy Scale. A comparison group of students from three SES levels also were included in the study. Comparisons were made on the scale scores among the non-dysphoric students, the dysphoric students, and the depressed patients. The results seem to support the relationship of sociotropy with other depression measures in both samples. However, several problems were encountered with the construct autonomy as it is conceptualized in the Sociotropy-Autonomy Scale

How dysfunctional are the dysfunctional attitudes in another culture?

The Dysfunctional Attitude Scale (DAS-A) has been used in many studies to measure depressogenic attitudes, vulnerability to depression and to assess the effectiveness of cognitive therapy. Despite its frequent use in research, no data have yet been reported on its item validity. The purpose of the present study was to investigate the item validity and psychometric properties of the DAS-A in the Turkish cultural context. The subjects were 345 university students. The locally adapted versions of the Beck Depression Inventory and the Automatic Thoughts Questionnaire were also administered. The reliability coefficients and the factor structure of the DAS-A were found to be similar to those reported in the West. However, the total mean was found to be unusually, high. The reason for this elevated mean score was as found to reside in the response patterns of the subjects to the reverse items. None of these 10 reverse items discriminated the dysphoric and non-dysphoric groups. A closer examination revealed these 10 items to reflect autonomous attitudes. It seems that these 10 reverse items do nothing but distort the mean scores and render cross-cultural comparisons difficult. Recent research on depression shows that, while autonomy may or may not be related to depression, sociotropy has consistent association with it. Researchers in other cultures and those working with minority and immigrant groups are warned against this bias inherent in the DAS-A