Yukselici, MH | Ince, R | Ince, AT

Article | 2004 | OPTICS AND LASERS IN ENGINEERING42 ( 3 ) , pp.277 - 287

A 90degrees geometry two-beam coupling configuration was used to investigate the storage properties of 0.03 mol% iron-doped lithium niobate. Photographs of the real image and the subsequently stored images showed partial spatial fading. The maximum diffracted light intensity against recording time rapidly increased, reaching a maximum before gradually decaying. Decay time constants against recording time, t(rec) varied in the same way as the diffracted intensity. Both plots reached a maximum at the same recording time of 3 min (I approximate to 0.8 W cm(-2)) and 12 min (I approximate to 0.4 W cm(-2)). Erasure decay times were found . . .to vary with recording time; the best value found in this work was 8.5 min. Erasure curves all displayed an initial oscillatory nature, which may result from oscillation of the diffraction grating via a slow damped oscillation of the constituent electrons. (C) 2004 Elsevier Ltd. All rights reserved Daha fazlası Daha az

Guner, ES | Watanabe, M | Hashimoto, N | Kadosaka, T | Kawamura, Y | Ezaki, T | Masuzawa, T

Article | 2004 | INTERNATIONAL JOURNAL OF SYSTEMATIC AND EVOLUTIONARY MICROBIOLOGY54 , pp.1649 - 1652

Previously, a novel, fast-growing spirochaete was isolated from the hard tick Hyalomma aegyptium, which infests tortoises (Testudo graeca), by using Barbour-Stoenner-Kelly (BSK) II medium; the tick samples were taken from the Istanbul area in northwestern Turkey [Goner et al. (2003). Microbiology 149, 2539-2544]. Here is presented a detailed characterization of the spirochaete. Electron microscopy revealed that strain IST7(T) is morphologically similar to other spirochaetes of the genus Borrelia and possesses 15 to 16 flagellae that emerge from both polar regions. PFGE analysis revealed the genome to comprise a linear chromosome of . . .approximately 1 Mb; two large linear plasmids of approximately 145 and 140 kb, and several small plasmids ranging from 50 to 20 kb in size were also found. The 16S rRNA gene sequence of this Borrelia isolate exhibited 99.4 to 99(.)8% identity with other strains isolated from H. aegyptium and less than 99 similarity with those of other Borrelia species. A phylogenetic tree, generated from 16S rRNA gene sequences, demonstrated that the spirochaete isolates from H. aegyptium clustered together and branched off from both Lyme-disease-related and relapsing-fever-associated Borrelia species. A single copy of the rrs gene was detected in the genome of strain IST7(T) by Southern hybridization. DNA-DNA hybridization results showed that strain IST7(T) was distinct from Lyme-disease-related Borrelia, Borrelia burgdorferi and the relapsing-fever-associated species Borrelia hermsii. The G+C content of strain IST7(T) is 30.0 mol%. From these genetic features, a novel Borrelia species, Borrelia turcica sp. nov., is proposed; the type strain is IST7(T) (=JCM 11958(T)=DSM 16138(T)) Daha fazlası Daha az

Balanli, A. | Ozturk, A.

Article | 2004 | Architectural Science Review47 ( 2 ) , pp.97 - 102

Examining buildings in terms of building biology might help to improve the environmental conditions within the buildings and to prevent the health problems caused by buildings. A conceptual model to examine buildings for this purpose is introduced in this work. After the determination of the building and its users the steps of the model are as follows: To examine the buildings • Identification of the indoor and outdoor environmental characteristics of the building. • Determination of the negative features of indoor and outdoor environments of the building. • Identification of the negative conditions due to those negative environment . . .al features. • Determination of the hazardous effects on health due to those negative conditions. • Identification of the negative characteristics of the user. • Determination of the health problem. To determine aspects of the building related sources of health problems • Identification of the health problem. • Identification of the negative characteristics of the user. • Determination of the hazardous effects on health. • Determination of the negative conditions which result in those hazardous effects. Determination of the negative characteristics of indoor and outdoor environment of the building which cause those negative conditions. © 2004 Taylor & Francis Group, LLC Daha fazlası Daha az

Yahyagil, Mehmet Y.

Article | 2004 | Yönetim Dergisi:İstanbul Üniversitesi İşletme Fakültesi İşletme İktisadı Enstitüsü15 ( 47 ) , pp.53 - 76

Bu çalışmanın amacı, Denison örgüt kültürü ölçme aracının geçerlik ve güvenirlik testlerinin yapılarak, Türkiye'de işletmelerin kültürel profillerinin analizi için kullanılıp, kullanılamayacağının belirlenmesidir. Ampirik bir çalışma olan bu uygulamanın birinci bölümü, örgüt kültürü kavramının gelişimine ilişkin bir alanyazın taramasıdır. İkinci bölümde inceleme konusunu oluşturan ölçme aracının 1995 yılında Daniel Denison ve Aniel Mishra tarafından geliştirilen teorik modeli ve kavramsal özellikleri açıklanmaktadır. Bu bölümde ayrıca özgün kavramsal modele ilişkin 4 temel ve 12 altboyutun özellikleri ve ölçme aracının Türkçe'ye uya . . .rlanma aşamaları hakkında bilgi verilmektedir. Üçüncü bölümde uygulamaya ilişkin teknik hususlar, son bölümde de, ölçme aracının güvenirlik ve geçerlik analizlerinin sonuçlan değerlendirilmektedir. Çeşitli aşamalardan oluşan bu analizlere göre, Denison örgüt kültürü ölçme aracının Türkçe'ye uyarlanmış, 36 maddeden oluşan 5'li Likert tipi soru formunun geçerli ve güvenilir bir araç olduğu kanıtlanmıştır. Güvenirlik katsayısı 0.89 olarak bulunan soru formu, örgüt kültürünün kavramsal boyutları ile gerçek yaşam arasında tutarlılık taşımakta ve içerik, yapı ve sınırlı ölçüde, eş-zamanlı geçerlik testleri açısından istatistiksel anlamda sağlıklı bir sonuca işaret etmektedir. Denison ölçme aracının ülkemizde kullanılabilmesi, bu alanda yapılacak teorik ve uygulamalı çalışmalara kolaylık getirecektir. The aim of this empirical study is to test validity and reliability of Denison organizational culture questionnaire for understanding whether this measurement instrument can be used to assess the cultural profiles of organizations in Turkey. The first section-reviews the relevant literature. The second section explains the 4 basic and 12 sub-conceptual dimensions of original theoretical model as developed by Daniel Denison and Aneil Mishra in 1995. This section also explains the steps involved in its adaption process into Turkish. Third section is about the technical procedures, and the last section presents the outcomes of the study. The questionnaire covers 36 items designed as 5 point Likert type instrument. The results of the analyses confirm that Turkish version of Denison questionnaire is both a valid and a reliable device. The instrument has a reliability coefficient value of 0.89, and the analyses indicate content, construct, and in certain extent, concurrent validity. The use of Denison questionnaire will be of help for carrying out research projects on organizational culture in Turkey Daha fazlası Daha az

Köse, G.T. | Hasirci, V.

Conference Object | 2004 | Advances in Experimental Medicine and Biology553 , pp.317 - 329

[No abstract available]

Sinmazişik, G. | Tirakyali, G. | Gülmez, T. | Akesi, S.

Conference Object | 2004 | Key Engineering Materials264-268 ( III ) , pp.2067 - 2070

For the In-Ceram™ system, the core needs to be sintered on a special plaster model and fired two times, first for 6 hours and then 2 more hours. In the fabrication of single piece jacket crowns with VITA In-Ceram™ sprint system, this time is reduced to 40 minutes. In this study by using the VITA In-Ceram™ sprint system, the pontic and crowns were prepared separately and these were connected to each other by a second sintering and glass infiltration procedure in order to decrease the firing time. The effects of this procedure on the fracture strength of the bridge prosthesis were investigated by 4-point bending tests on standard samp . . .les representing the pontic and crowns of a bridge prosthesis. Three different sample groups were prepared for the 4-point bending tests : a control group consisting of monolithic samples, a second group comprising separate samples with a connect distance of 1.5 mm and a third one having a connect distance of 1 mm. Whereas the control group had better bending strength values,there were no statistically significant differences between the strength values of the specimens of the other two groups. Scanning Electron Microscopy investigations were carried out to examine the fracture surfaces of the bending specimens Daha fazlası Daha az

Budak, Yasemin | Işıtmangil, Gülbu | İnal, Şebnem

Article | 2004 | İstanbul Üniversitesi İstanbul Tıp Fakültesi Mecmuası67 ( 3 ) , pp.149 - 152

Bu çalışmanın amacı preeklamptik gebelerde kan lipid peroksidasyon ürünlerinin artması ve antioksidan düzeylerinin azalması ile ilgili hipotezi araştırmaktır. Bu amaçla normal gebe (n16) ve preeklamptik gebelerden (n16) açlık venöz kanı alındı. Plazma total antioksidan aktivite ve tiyobarbitürik asitle reaksiyona giren maddelerin (TBARS) düzeyleri kolorimetrik yöntemle ölçüldü. Çalışmanın bulgularına göre normal ve preeklamptik hamilelerin plazma total antioksidan aktivite değerleri ve TBARS değerleri arasında istatistiksel olarak anlamlı bir fark bulunamadı. Ayrıca sağlıklı gebe kadınlardan oluşan grupta total antioksidan aktivite . . .ve TBARS değerleri arasında negatif yönde, orta güçte bir korelasyon tespit edildi (r-0.60, p0.05). Buna karşılık, preeklampsili gebe kadınlardan oluşan grupta herhangi bir bağıntı tespit edilemedi (r0.05, p0.05). Bu bulgular ışığında preeklamptik hastalarda antioksidan savunma sistemleri ve lipid peroksidasyonu arasında bir dengesizlik olduğu ileri sürülebilir. Evaluation of the imbalance between antioxidant activity and lipid peroxidation in preec-lamptic patients. The objective of this study is to test the hypothesis that maternal plasma lipid peroxidation products are increased and antioxidants are decreased in women with mild pre-eclampsia. Fasting venous plasma were collected from normal pregnant (n16) and mild pre-eclamptic women (n16). Plasma total antioxidant status and thiobarbituric acid reactive substances (TBARS) were measured by colorimetric assay. Plasma maternal concentrations of total antioxidant status and thiobarbituric acid reactive substances (TBARS) were not significantly different in pre-eclampsia as compared with normal pregnancy (p> 0.05). When the variables in the same groups were measured, we found a negative correlation between total antioxidant status and TBARS in the normal group (r -0.60, p<0.05). In the mild preeclamptic women we could not find a correlation between total antioxidant status and TBARS (r0.05, p>0.05). The findings in this study show that there is an imbalance between antioxidant defences and lipid peroxidation in preeclamptic patients Daha fazlası Daha az

Vickers, E.R. | Kasza, A. | Kurnaz, I.A. | Seifert, A. | Zeef, L.A.H. | O'Donnell, A. | Sharrocks, A.D.

Article | 2004 | Molecular and Cellular Biology24 ( 23 ) , pp.10340 - 10351

Members of the ternary complex factor (TCF) subfamily of the ETS-domain transcription factors are activated through phosphorylation by mitogen-activated protein kinases (MAPKs) in response to a variety of mitogenic and stress stimuli. The TCFs bind and activate serum response elements (SREs) in the promoters of target genes in a ternary complex with a second transcription factor, serum response factor (SRF). The association of TCFs with SREs within immediate-early gene promoters is suggestive of a role for the ternary TCF-SRF complex in promoting cell cycle entry and proliferation in response to mitogenic signaling. Here we have inv . . .estigated the downstream gene regulatory and phenotypic effects of inhibiting the activity of genes regulated by TCFs by expressing a dominantly acting repressive form of the TCF, Elk-1. Inhibition of ternary complex activity leads to the downregulation of several immediate-early genes. Furthermore, blocking TCF-mediated gene expression leads to growth arrest and triggers apoptosis. By using mutant Elk-1 alleles, we demonstrated that these effects are via an SRF-dependent mechanism. The antiapoptotic gene Mcl-1 is identified as a key target for the TCF-SRF complex in this system. Thus, our data confirm a role for TCF-SRF-regulated gene activity in regulating proliferation and provide further evidence to indicate a role in protecting cells from apoptotic cell death Daha fazlası Daha az

Gençay, K. | Seymen, F. | Selvi, S. | Kiziltan, B.

Article | 2004 | Quintessence International35 ( 7 ) , pp.560 - 562

Objectives: Since the highly alkaline pH of calcium hydroxide is considered by many to be responsible for its biologic activity, the possible variations of pH induced by the different calcium hydroxide liners are accepted as a major concern. The aim of the present study was to determine the pH changes of five different calcium hydroxide liners and variations of pH levels at different time intervals. Method and materials: The materials tested were Dycal, Life, CaNc, Dycal VLC, and Calcident 450. Samples were prepared according to manufacturer instructions and by using plastic molds; five standard samples from each material were prepa . . .red. The samples were then placed in separate vials, containing 10 mL deionized water (pH 7.0), and stored at room temperature (20°C). The pH measurements were taken 1 hour, 24 hours, 3 days, and 7 days after mixing. The pH variations of each material at the given time intervals were recorded, and the means were calculated. Results: Statistical analysis showed significantly high differences between the mean pH values induced by each material at all time intervals. The highest value for the first-hour measurement was for Dycal VLC, and the highest values for the other time intervals were for Calcident 450. The pH values of the materials exhibited statistically significant differences among all the time intervals. Conclusion: All materials changed the pH of deionized water toward alkaline Daha fazlası Daha az

Parmaksizoglu, F. | Beyzadeoglu, T.

Article | 2004 | Acta orthopaedica et traumatologica turcica38 ( 1 ) , pp.60 - 66

OBJECTIVES: We evaluated the results of lengthening of the phalanges by callus distraction in traumatic amputations of the fingers. METHODS: We treated traumatic amputations of 16 fingers of 13 male patients (mean age 27.7 years; range 12 to 43 years) by callotasis of the phalanges. Callus distraction was performed with a rate of 1 mm/day using a unilateral dynamic external fixation device. The mean follow-up period was 42 months (range 12 to 80 months). RESULTS: The mean lengthening was 24 mm (range 18 to 26 mm) and 21 mm (range 18 to 26 mm) for the thumbs and the other fingers, respectively. The achieved thumb length provided adeq . . .uate depth and width of the first web space and enabled functional improvement in the ability of gripping, and pulp-to-pulp and pulp-to-side pinching. In the absence of flexor pollicis longus, the mean strength of the thumbs was 7 kg (range 5 to 9 kg), amounting to 65% of the normal side. Lengthening of the other fingers resulted in improved functioning of the hand. The mean healing index (number of months per centimetre of lengthening) was 1.7 months/cm (range 1.6 to 2.1 months/cm) and 1.6 months/cm (range 1.4 to 1.9 months/cm) in the thumbs and the other fingers, respectively. Pin tract infections were observed in four phalanges. CONCLUSION: Callotasis of the proximal phalanx of the thumb is an effective reconstruction method to compensate for the loss of distal phalanx and to alleviate functional problems due to shortness. It may also be applied to the phalanges of the other fingers in patients who do not accept ray resection with or without transposition Daha fazlası Daha az

Ülgentürk, S. | Çanaki¸oglu, H.

Article | 2004 | Journal of Pest Science77 ( 2 ) , pp.79 - 84

Ornamental plants play an increasingly important role in urban habitats in Turkey. Scale insects are a serious pest group that attack ornamental plants. In this study, a total of 67 species of Coccoidea belonging to 7 families, which are harmful to ornamental plants, are given in Tables 1, 2, and 3. These tables are based on the author's data and on bibliographic sources. The most numerous families are Diaspididae (31), Coccidae (23), Pseudococcidae (7), Eriococcidae (3), and the Margarodidae, Kermesidae and Astereolecaniidae (1). Twenty-one of these species are harmful to flowering fruit and deciduous trees, 5 species are harmful t . . .o conifers, while 15 species are important orchard pests. Their hosts and distributions are also taken into consideration. © Springer-Verlag 2004 Daha fazlası Daha az

Şuhubi, E.S.

Article | 2004 | International Journal of Engineering Science42 ( 15-16 ) , pp.1729 - 1751

The groups of equivalence transformations for a family of balance equations of arbitrary order involving arbitrary number of independent and dependent variables are investigated. Equivalence groups are essentially much more general than symmetry groups in the sense that they map equations containing arbitrary functions or parameters onto equations of the same structure but with different functions or parameters. We attack the problem of determination of group structure of a system of arbitrary balance equations through exterior calculus. The analysis is reduced to determine isovector fields of a closed ideal of an exterior algebra o . . .ver an appropriate differentiable manifold dictated by the structure of the differential equations by employing almost solely algebraic operations. The isovector fields induce point transformations, which are none other than the desired equivalence transformations, generated by their orbits which leave that particular ideal invariant. The determining equations are fully obtained. It is shown that symmetry transformations can also be deduced directly from equivalence transformations. © 2004 Elsevier Ltd. All rights reserved Daha fazlası Daha az