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Objective Acute appendicitis (AA) is the most common abdominal surgical emergency worldwide. Several infection and inflammation imaging methods have been used in a limited number of cases. Gallium-68 ( 68 Ga) has recently been investigated as an infection and inflammation imaging agent. The aim of our study was to produce 68 Ga-citrate in an automated synthesis unit and perform 68 Ga-citrate PET/CT imaging in rabbits with experimentally induced AA. Furthermore, this study aimed to investigate and correlate PET/CT findings with those of histopathological and biochemical examinations. Methods 68 Ga-citrate was synthesized using the cationic method in an automatic synthesis unit. Twelve rabbits of the New Zealand strain ( Oryctolagus cuniculus ) were divided into two groups. In the AA group (n = 6), the appendices of the rabbits were surgically ligated. In the sham group (n = 6), the abdomen was surgically opened and closed. All rabbits were imaged using 68 Ga-citrate PET/CT at 12, 24 and 36 h following the establishment of the experimental models, and at 36 h, all rabbits were appendectomised. Appendices were examined histopathologically and blood samples were drawn from all rabbits at the beginning and end of the experimental process. Interleukin-6 (IL-6) and procalcitonin (Pct) levels were measured. PET/CT results were compared statistically with histopathological and biochemical references. Results The labelling efficiency of 68 Ga-citrate was more than 98%. The sensitivity, specificity and accuracy of 68 Ga-citrate PET/CT in AA were 100%, 83.3% and 81.7%, respectively. IL-6 and Pct levels at 36 h in the AA group were significantly higher than those in the sham group and at baseline (p < 0.05). Conclusions 68 Ga-citrate was synthesized in an automatic synthesis unit for the first time, and 68 Ga-citrate uptake was shown using PET/CT in a histopathologically and biochemically confirmed experimental AA rabbit model.

The applicability of surface-enhanced Raman scattering (SERS) on silver nanoparticles for characterization of interaction between the phthalocyanine molecule and amyloid fibril was studied using the axially coordinated Hf phthalocyanine dichloride and fibrils of amyloidogenic protein insulin. The SERS spectra of the phthalocyanine were obtained; the analytical enhancement factor was estimated to be in the range from 4 to 6 ×104. An intensity enhancement in its SERS spectra caused by the presence of fibrillar insulin was observed. Deviation of this enhancement with the change of fibrillar insulin concentration was manifested. © 2018 Taylor & Francis. 114Z464 This work was supported by NASU-TUBITAK joint project 114Z464.

Background: direct immunofluorescence (DIF) panels are usually ordered for clinically suspected cutaneous vasculitis, but their positivity rate is variable, and their prognostic significance is not clear to date. Objective: the study aims to investigate the systemic involvement rate in leukocytoclastic vasculitis (LCV) patients and the potential clinical and laboratory associations with systemic involvement, including DIF findings. Methods: a retrospective study of patients with histopathologically proven cutaneous LCV examined in the dermatology department between 2013 and 2017 was performed. Results: Of the 81 patients (mean age, 50.6 years), 42 (52%) were male. The mean time between the appearance of skin lesions and biopsy was 23.1 days, ranging from 2 to 180 days. DIF showed overall positivity of 90.1%, and C3 was the most frequent immunoreactant (82.7%). Any kind of extracutaneous involvement was present in 47 (58%) of patients, with renal involvement being the most frequent (53.1%), followed by articular (18.5%) and gastrointestinal (11.1%) involvement. The presence of renal disease was associated with the detection of IgG in the lesional skin (p = 0.017), and with the absence of IgM in the lesional skin (p = 0.032). There was a significant association between C3 deposition and joint involvement (p = 0.05). Study limitations: this is a single-center study with a retrospective design. Conclusion: DIF seems to be a useful ancillary diagnostic tool in the evaluation of cutaneous vasculitis, but the relationship between DIF findings and systemic involvement needs to be further elucidated due to contradictory data in the current literature., NA

This study analyzes cash-cash flow sensitivity by comparing financially constrained and unconstrained firms in eight markets. 486 manufacturing firms are examined between 2005 and 2018 using the Generalized Method of Moments. These firms are categorized based on size, age, and Size-Age, Sales-Age, and Kaplan and Zingales indices. We find that both constrained and unconstrained firms evince positive cash-cash flow sensitivity. Although unconstrained firms obtain external financing easily, they prefer to first use internally generated funds in accordance with the pecking order theory. The results also reveal that cash-cash flow sensitivity cannot be used to test financial constraints in emerging markets., Bu çalışma sekiz gelişmekte olan ülkede yer alan finansal açıdan kısıtlı ve kısıtlı olmayan firmaları karşılaştırarak nakit-nakit akışı duyarlılığını analiz etmektedir. 486 üretim firması 2005-2018 yılları arasında Genelleştirilmiş Momentler Metodu tahmincileri uygulanarak analiz edilmiştir. Bu firmalar büyüklük, yaş ve Size-Age (SA1), Sales-Age (SA2), ve Kaplan-Zingales (KZ) endekslerine göre kategorilere ayrılmıştır. Analiz sonuçlarına göre hem kısıtlanmış hem de kısıtlanmamış firmaların pozitif nakit-nakit akışı duyarlılığı gösterdiği bulunmuştur. Kısıtlanmamış firmalar dış finansmanı kolaylıkla temin edebilirken, finansal hiyerarşi teorisine dayalı olarak öncelikle kendi iç fonlarını kullanmayı tercih etmektedirler. Sonuçlar ayrıca nakit-nakit akışı duyarlılığının gelişmekte olan ülkelerde finansal kısıtlamaları test etmek için kullanılamayacağını da göstermektedir.

Bu çalışmanın amacı farklı hedge fonu stratejilerinin performanslarını karşılaştırmak ve hedge fonları ile çeşitlendirme olasılıklarını değerlendirmektir. Bu çalışmada 2001-2020 zaman periyodunda farklı hedge fon stratejilerinin (endeks bazında) performansları analiz edilmiştir. Alternatif risk ölçütleri kullanılarak hedge fonları performansları ölçülmüştür. Bunlardan 4 varlık fiyatlama modeline (CAPM, Fama-French 3 Faktör, Carhart ve Fama-French 5 Faktör modelleri) dayanan Alpha, diğeri ise Sharpe rasyosudur. Çalışmanın bulguları, hemen hemen tüm hedge fon stratejilerinin kıyas alınan getiriden (MSCI Dünya Endeksi) daha iyi performans gösterdiğini ve risk/getiri ölçütleri açısından üstün olduğunu ortaya koymuştur. Riske göre ayarlanmış performansların hesaplanmasında kullanılan alternatif risk ölçütleri, hedge fon stratejilerinin performans sıralamasında önemli bir değişikliğe neden olmamıştır. This study aimed at comparing the performances of distinct hedge fund strategies and assessing the diversification opportunities using hedge funds. This paper analyses the overall performance of distinct hedge fund strategies (as indices) for the period of 2001-2020. Hedge fund performances are compared using alternative risk adjusted performance metrics; first, alpha based on four asset-pricing models (CAPM, Fama-French 3 factor, Carhart and FamaFrench 5 factor models); then, the Sharpe ratio. The findings of the study revealed that almost all hedge fund strategies outperform the benchmark return (MSCI World Index) and are superior in terms of risk/return measures. The alternative risk metrics used in the calculation of risk-adjusted performances did not cause a dramatic change in the rank ordering of the hedge fund strategies.