In this paper, we analyze the incentives of an incumbent and an entrant to migrate from an "old" technology to a "new" technology, and discuss how the terms of wholesale access affect this migration. We show that a higher access charge on the legacy network pushes the entrant firm to invest more, but has an ambiguous effect on the incumbent's investments, due to two conflicting effects: the wholesale revenue effect, and the business migration effect. If both the old and the new infrastructures are subject to ex-ante access regulation, we also find that the two access charges are positively correlated.

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The nature of competition in local access telecommunications networks is shaped by the "build-or-buy" decisions of the competitive local exchange carriers (CLECs). Facility-based competition takes place when a CLEC "builds" its own infrastructure (e.g., wireless local loop, cable network, fiber-optic network, satellite network), whereas service-based competition takes place when a CLEC "buys" some network elements from the incumbent local exchange carrier (ILEC). Two main ways to achieve servicebased competition are resale and local-loop unbundling. 1 A serious concern with mandatory local-loop unbundling is that it may undermine incentives for facility-based competition. 2 In order to achieve transition to facility-based competition, Jerry A. Hausman and J. Gregory Sidak (2004) suggest that regulators allow the prices for fixed unbundled elements to increase over time, while Thomas Jorde et al. (2000) suggest that mandatory unbundling should sunset after the passage of two years or upon the entry of a facility-based competitor.In this paper, we challenge the implicit assumption behind sunset clauses, 3 namely that the ILEC would either deny unbundling or charge too high a price for its network elements in the absence of regulation. We do this by analyzing an unregulated ILEC's decision regarding unbundling in an unregulated environment. 4 We make the realistic assumption that the cost of building the facility declines over time. In a dynamic setting we show that an unregulated incumbent sets a rental path for its local loop, which delays facility-based entry, compared to the case in which there is no unbundling. The equilibrium rental path set by the unregulated incumbent is prohibitively high at the initial phases when there is no effective threat of facility-based entry, and it is decreasing over time during later phases following the rise of the entrant's opportunity cost of leasing lines. We argue that neither allowing higher prices for unbundled elements over time nor setting a sunset clause would suffice to induce facility-based competition. The ILECs that initially resist unbundling requirements will tend to charge attractive access prices (relative to the CLECs' alternatives) for their infrastructure, which become less essential over time. Therefore, the appropriate policy for regulators is to commit to ban unbundled access when facilitybased entry becomes feasible and socially desirable.

Currently, coronary artery disease (CAD) is considered a major ailment in humans with widespread prevalence. CAD also accounts for high mortality rates around the world that involves several known risk factors. Chemerin is a novel adipokinine that is associated with inflammation and adipogenesis. Furthermore, experimental and clinical data indicate that localized as well as circulating chemerin expression and activation are elevated in numerous metabolic and inflammatory diseases including psoriasis, obesity, type 2 diabetes, metabolic syndrome and cardiovascular disease. Chemerin is accepted as being a strong marker because the serum chemerin levels are increased in a CAD condition. However, the chimeric characteristics of chemerin have not been fully investigated. Although chemerin is known to be responsible for CAD development among other factors, authors still investigate it at the marker level. This review focuses on chemerin expression, processing, biological function and relevance to human diseases, and on the role of chemerin in the maintenance of a cardiovascular disease.

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Hemşirelik eğitiminde simülasyon kullanımına ilişkin çalışmaların sistematik incelemesi, bilgi-beceri ve eleştirel düşünme-klinik karar vermeyi değerlendiren araştırmalar olarak iki grup altında gerçekleştirilmiştir. Çalışmaya dahil edilen makalelerde deneysel, yarı deneysel ve tanımlayıcı-ilişki arayıcı araştırma tasarımlarının kullanıldığı saptanmıştır. Araştırmaların 7'sinde, hemşirelik bilgi ve becerilerinin kazandırılmasında simülasyon ile eğitimin etkili olduğu belirlenmiştir. Ayrıca 10 araştırmada da simülasyon ile eğitimden sonra öğrencilerin, eleştirel düşünme, öz etkililik ve öz güven düzeylerinde artma saptanmıştır. Sonuç: Hemşirelik eğitiminde simülasyonun, öğrenciye bilgi ve beceri kazandırmasının yanı sıra eleştirel düşünme, öz etkililik ve öz güvenin de gelişmesine katkı sağlayan bir öğrenme yöntemi olduğu görülmektedir.

Objective: In this study, we aimed to identify the factors influencing the use of ambulance among patients admitted to two Turkish hospitals with acute coronary syndrome (ACS). Methods: Overall, 330 with a mean age of 55±13 years, hospitalized patients with ACS at 2 different hospitals were included in this prospective cohort study. The factors influencing the use of ambulance hospital were investigated through a questionnaire. The comparisons were made between two groups regarding use of ambulance. The predictors of the use of ambulance were determined using multiple logistic regression analysis. Results: Despite the high rate of knowing the emergency service number of "112", of the 330 patents, only 96 (29%) used ambulance. Ambulance users had shorter arrival duration with median of 60 min vs 120 min (p=0.03). Presenting with ST elevation myocardial infarction (OR=3.127, 95% CI: 1.555-6.2877, p<0.001), severity of chest pain (OR=2.665, 95% CI: 1.938-3.665, p<0.001), presence of accompanying symptoms such as dyspnea (OR= 5.510, 95% CI: 2.614-11.614, p<0.001), dizziness (OR=4.172, 95% CI: 1.901-9.154, p<0.001) and vomiting (OR=3.756, 95% CI: 1.521-9.272, p=0.004), knowledge of cardiac risk factors (OR=10.512, 95% CI: 4.497-24.572, p<0.001) or chest pain related to heart attack and the importance of quickly seeking for medical care by calling ambulance (OR= 4.184, 95% CI: 2.528-6.926, p<0.001) are the factors associated with ambulance use. Conclusion: Using ambulance was in a very low rate among our study patients with ACS. Severity of symptoms, type of ACS and knowledge are seemed to be related with increased ambulance use. Informative health educational programs can be organized to achieve a behavioral change in using of ambulance. (Anadolu Kardiyol Derg 2013; 13: 516-22) Key words: Ambulance use, acute coronary syndrome, regression analysis Original Investigation Özgün Araşt›rma 516ÖZET Amaç: Ambulans kullanılması akut koroner sendromlu (AKS) hastaların hastaneye nakli sırasında sadece hızlı değil, aynı zamanda güvenilir ulaşım şeklidir. Bu çalışma AKS tanısı ile iki ayrı merkeze başvuran hastalarda ambulans kullanımını etkileyen faktörlerin belirlenmesi amaçlanmıştır. Yöntemler: Türkiye'de 2 ayrı hastanede AKS tanısı ile hastaneye yatırılan ve yaş ortalaması 55±13 olan toplam 330 hasta bu prospektif kohort çalışmaya dahil edilmiştir. Hastaların hastaneye ulaşım şeklini etkileyen faktörler bir anket formu aracılığıyla araştırılmıştır. Hastalar ambulans kullanıp kullanmadıklarına göre iki gruba ayrılarak karşılaştırmalar yapılmıştır. Ambulans kullanımını belirleyen faktörler çoklu lojistik regresyon analizi ile değerlendirilmiştir. Bulgular: Acil servis numarası "112"nin yüksek oranda biliniyor olmasına rağmen, 330 hastanın sadece 96'sı (%29) ambulans kullanırken, geri kalan 234 (%71) hasta kendi ulaşımını sağlamıştır. Ambulans kullananların hastaneye ulaşım süreleri (ortanca 120 dakikaya karşılık 60 dakika olarak) daha kısa olmuştur (p=0,03). ST yükselmeli miyokart enfarktüsü ile başvurma (OR=3,127, %9...