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In this paper, point estimation problem of two unknown parameters of the unit log-log distribution is examined. For point estimation, six methods of estimate such as maximum likelihood, maximum product spacing, Anderson-Darling, least squares, weighted least squares, and Cramer-von Mises are examined in detail. Extensive simulation experiments are conducted to compare the effectiveness of these estimators based on bias and mean squared errors. According to the simulation results, it is seen that all estimators performed well in terms of two criteria and take close values in case of large sample. Moreover, practical data applications are performed for all estimators. Results of the Kolmogorov-Smirnov statistics are reported for all estimators in practical applications.

Tarım sektörü; istihdama, gayrisafi yurtiçi hasılaya, dış ticarete ve özellikle kırsal kalkınmaya yaptığı önemli katkılardan dolayı hem gelişmiş hem de gelişmekte olan ülkelerin ekonomisinde önemli bir yere sahiptir. Bu nedenle sektörün ekonomik performansını yakından izlemek ileriye dönük iktisadi büyüme hedefi için oldukça ehemmiyetlidir. Bu doğrultuda çalışmada OECD içerisinde en yüksek tarım sektörü dış ticaret hacmine sahip 10 ülkenin (ABD, Almanya, Hollanda, Fransa, İngiltere, İtalya, Japonya, Kanada, İspanya, Belçika) söz konusu sektördeki ekonomik performansını analiz etmek amaçlanmaktadır. Çalışmada çok kriterli karar verme yöntemlerinden Bulanık Analitik Hiyerarşi (AHP) Buckley yöntemi ile ülkelerin tarım sektörüne ait ekonomik performansları tespit edilirken ülkelerin sıralanması için TOPSIS yöntemi tercih edilmiştir. Ülkelerin 2000-2019 yıllarına ait yıllık verilerinin kullanıldığı çalışmanın değişkenleri gıda TÜFE, büyüme oranı, tarımda enerji kullanımı, tarım istihdam oranı, kent nüfus oranı, net ihracat, tarım net ihracatı ve tarımsal hammadde ithalat ve ihracatıdır. Araştırma sonucuna göre İtalya 2000-2018 yıllarında en yüksek performansı sergileyen ülkedir. Seçilen ülkeler arasında İtalya tarım sektörü dış ticaret hacminde altıncı sırada yer almasına rağmen, diğer ilgili değişkenler dikkate alındığında tarım sektöründe göreceli olarak diğer ülkelerden daha iyi bir performans sergilediği görülmektedir. 2019 yılında ise birinci sırada yer alan ülke ABD’dir.

We optimized ultrasound-assisted alcohol-based deep eutectic solvent dispersive liquid-phase microextraction for separation and preconcentration of quercetin in wine and food samples by experimental design based on central composite design. Five different alcohol-based deep eutectic solvents were prepared and tested for quercetin extraction. The effect of important parameters and matrix components were optimized. After optimization, the determination of quercetin was performed at 385 nm using spectrophotometry. Analytical data such as detection limit, working range and preconcentration factor were found as 6.1 μg/L, 20-850 μg/L, and 120, respectively. The selectivity of the optimized extraction conditions for quercetin was investigated in the presence of different matrices. The validation of the method was investigated by reproducibility, repeatability and recovery studies, as well as by comparing the analytical results obtained from real samples with the reference method. Lastly, the recommended procedure was successfully applied for the extraction and quantification of quercetin in wine and food samples.

Objectives: To assess differential effects of different materials combined with allograft on bone-to-implant contact and newly formed bone formation in dental implants with coronal defects histomorphometrically. Materials and Methods: The study was conducted on 24 male New Zealand white rabbits. Dental implants (3.0 × 10 mm) were placed at the center of defects (9 mm diameter, 4 mm depth) created in the tibial bones of the rabbits. Graft (GF, n=8), graft + rifamycin (GR, n=8), and graft + black cumin oil via orogastric route (GB, n=8) were applied on the coronal aspects of the implants for 28 days. Undecalcified histomorphometric analyses were conducted on slides stained with toluidine blue. Results: Bone-to-implant contact was 46.57% ± 3.59% in the graft, 67.12% ± 3.64% in the graft+rifamycin, and 55.62% ± 4.37% in the graft+black cumin oil groups. The percentage of new bone formation at the defect area was 34.71% ± 4.11% in the graft, 55.37% ± 4.89% in the graft + rifamycin, and 45.75% ± 3.69% in the graft + black cumin oil groups. In terms of new bone formation and bone-to-implant contact, graft + rifamycin and graft + black cumin oil groups were significantly different from the graft group. The differences between the graft + rifamycin and graft + black cumin oil groups were also statistically significant. Conclusion: Allogreft + rifamycin and orogastric black cumin oil were found to have positive effects on bone healing at sites with coronal defects. Rifamycin showed significantly greater favorable effects on bone-to-implant contact and new bone formation compared to black cumin oil.

Pathologic halitosis has been classified into 5 types: oral, airway, gastroesophageal, blood-borne and subjective, respectively. Type 1 (oral) halitosis mostly takes origin from anaerobic bacterial activities on oral surfaces. The role of anaerobic bacterial activities is clearly demonstrated, but despite the large number of anectodal claims, the role of Candida in patients with halitosis has not been adequately investigated. The aim of this study was to confirm the relationship between Candida and halitosis. A total of 136 subjects were enrolled and divided into two groups. The study group comprised of 69 patients with halitosis who had over 0.7 ppm H2S concentration in their oral cavity and the control group comprised of 67 healthly subjects. Self assesment scores for halitosis, Candida colony counts in saliva samples, oral NH3, SO2, H2S, H2 and volatile organic gas concentrations were recorded. H2S producing capacity of subjects was quantified by applying cysteine challenge test. Candida samples were taken from the mouths of the patients with and without halitosis, and Candida albicans isolates were inoculated into broth medium. After 3 days of incubation at 37oC, gas concentrations of the headspace of the flasks were read by a portable multigas detector. The rate of Candida positivity was 44.9% in the study group while it was 46.3% in the control group. There was no statistical significant difference between the groups according to the Candida growth (p= 0.561). The oral gas concentrations were comparable in both groups (p< 0.05). Oral H2S concentration increased 9.65 fold with 20 mM cysteine rinse in patients with halitosis while it was increased 5.8 fold in controls. Self assesment for halitosis were well correlated with clinical signs (p= 0.001, r= 0.8). Concentrations of hidrogen and organic gases were found to be increased in all Candida culture media. In this study, no relationship between the presence of Candida and oral halitosis was detected. As a result, there is no need for diets similar to Candida diet in the treatment of halitosis. On the other hand, cysteine challenge can be a useful diagnostic tool. In addition, portable gas detectors can be used as a convenient and practical halitometer to quantify halitosis.

In this study, a new life testing method called “progressive type-I interval censoring with part time operator” is introduced. We obtained the maximum likelihood estimators for parameters of Weibull distribution. A simulation study is conducted to investigate the mean biases, mean variances and MSE (Mean Squared Error)'s of estimates. The results are compared for sampling progressive type-I interval censored data, part-time operator and complete data.

Purpose - This study investigates whether size of 112 publicly listed firms in manufacturing sector affects their profitability in Turkey during the period 2005-2013. Methodology - Dynamic panel data approach (i.e. two-step system GMM estimator) taking into account potential endogeneity of firm-level variables is employed to estimate the effect of alternative firm size indicators on firm profitability. Findings- Estimation results suggest that after controlling for financial risk, liquidity level, growth opportunities, unsystematic risk, firm age, and the other factors, the indicators of firm size measured by firm’s assets, sales and number of employees tend to have a positive influence on the profitability of firm measured by operating return on assets. Conclusion- There is enough statistical evidence to support a linear relation between firm size measures and profitability of firms in the period analyzed. However, our empirical results do not support the quadratic or cubic association between size measures and profitability.

In this research article, a novel and green deep eutectic solvent-based microextraction (DES-ME) procedure based on chemometric-assisted (CA) optimization was developed for the extraction of caffeine in foods and beverages prior to its spectrophotometric determination. Ultrasound was used to accelerate the extraction of caffeine. Deep eutectic solvents (DES), prepared in an ultrasonic bath at 20–60 min for 60–80°C, were used as extraction solvents. The important experimental variables (pH, DES amount, temperature, sonication time and metal concentration) were modelled and optimized using response surface methodology (RSM) based on central composite design (CCD). Under the optimum conditions, the proposed method allowed the determination of caffeine with limits of detection (LOD, 3sblank/m) and quantification (LOQ, 3sblank/m) of 7.5 and 25.0 µg L?1, respectively. For 40 µg L?1 and 100 µg L?1 of caffeine (n = 5), relative standard deviations (RSDs%) and recoveries% were 1.2–1.6% and 96.7–98.2%, respectively. Validation studies (accuracy, precision, trueness, reliability and selectivity) of the method were performed before the analysis of real samples. The results showed that the combination of the CCD with the DES-ME can be considered as a new perspective for the extraction and determination of caffeine in foods and beverages. © 2019, © 2019 Taylor & Francis Group, LLC.

Pathologic halitosis has been classified into 5 types: oral, airway, gastroesophageal, blood-borne and subjective, respectively. Type 1 (oral) halitosis mostly takes origin from anaerobic bacterial activities on oral surfaces. The role of anaerobic bacterial activities is clearly demonstrated, but despite the large number of anectodal claims, the role of Candida in patients with halitosis has not been adequately investigated. The aim of this study was to confirm the relationship between Candida and halitosis. A total of 136 subjects were enrolled and divided into two groups. The study group comprised of 69 patients with halitosis who had over 0.7 ppm H2S concentration in their oral cavity and the control group comprised of 67 healthly subjects. Self assesment scores for halitosis, Candida colony counts in saliva samples, oral NH3, SO2, H2S, H2 and volatile organic gas concentrations were recorded. H2S producing capacity of subjects was quantified by applying cysteine challenge test. Candida samples were taken from the mouths of the patients with and without halitosis, and Candida albicans isolates were inoculated into broth medium. After 3 days of incubation at 37oC, gas concentrations of the headspace of the flasks were read by a portable multigas detector. The rate of Candida positivity was 44.9% in the study group while it was 46.3% in the control group. There was no statistical significant difference between the groups according to the Candida growth (p= 0.561). The oral gas concentrations were comparable in both groups (p0.05). Oral H2S concentration increased 9.65 fold with 20 mM cysteine rinse in patients with halitosis while it was increased 5.8 fold in controls. Self assesment for halitosis were well correlated with clinical signs (p= 0.001, r= 0.8). Concentrations of hidrogen and organic gases were found to be increased in all Candida culture media. In this study, no relationship between the presence of Candida and oral halitosis was detected. As a result, there is no need for diets similar to Candida diet in the treatment of halitosis. On the other hand, cysteine challenge can be a useful diagnostic tool. In addition, portable gas detectors can be used as a convenient and practical halitometer to quantify halitosis.

Vibrational scale factors were determined for the M06-2X method. The calculated scale factors were supported statistically. The main objective is to determine the concordance between frequencies. Descriptive statistics of the experimental and corrected frequencies are given. The relationship between corrected and experimental frequencies is formed by a simple linear regression method. The Concordance Correlation Coefficient determines the consistency between the two variables. It evaluates the direct relationship between X and Y variables measured under constraints. Also, the difference between the mean of the two variables was tested. All results are interpreted and presented with their graphs.

Amac: Bu calismanin amaci farkli egitim disiplinlerinde ogrenim goren universite ogrencilerinde, egitimin sigara aliskanligi ve muhtemel uyku bruksizmi egilimine olan etkisini ve varsa sigara ve muhtemel uyku bruksizminin iliskisini degerlendirmektir. Gerec ve Yontemler: Calisma, Cumhuriyet Universitesi Dis Hekimligi Fakultesi Agiz, Dis ve Cene Radyolojisi Anabilim Dali’na 2012- 2014 tarihleri arasinda basvuran, 17-34 yas araliginda 262’si kiz (%57) ve 195’i (%43) erkek olmak uzere 457 universite ogrencisinin doldurdugu formlar uzerinden retrospektif olarak yurutuldu. Bu formlarda ogrencilerin, sosyodemografik bilgileri, okuduklari bolum, sigara aliskanligi ve muhtemel uyku bruksizm varligina yonelik sorulara verdikleri cevaplar kaydedildi. Bulgularin istatistiksel degerlendirilmesi SPSS. 20 programinda ki-kare analizi kullanilarak yapildi. Bulgularin istatistiksel degerlendirilmesi SPSS. 20 programinda ki-kare analizi kullanilarak yapildi. Bulgular: Sigara aliskanligi muhendislik bolumu ogrencilerinde ve erkeklerde anlamli derecede yuksek bulundu (p 0.05). Cinsiyet ve egitim disiplinlerinin muhtemel uyku bruksizmiyle arasinda anlamli bir iliski yoktu (p>0.05). Sonuclar: Egitim disiplinlerinin sigara aliskanliginda etkisi bulunurken, muhtemel uyku bruksizmi uzerinde bu etki gorulmemistir. Anahtar Kelimeler: bruksizm, fakulte, sigara aliskanligi, universite ogrencisi.

Bu çalışmada yeni bir yaşam testi metodu olan yarı-zamanlı operatörlü ilerleyen tür tip-I aralık sansürleme tanıtılmıştır. Weibull dağılımı parametreleri için en çok olabilirlik tahminleri elde edilmiştir. Tahminlere ait ortalama yan değerlerini, ortalama varyanslarını ve hata kareler ortalamasını (MSE) araştırmak için simülasyon çalışması yapıldı. Elde edilen sonuçlar, ilerleyen tür tip-I aralık sansürlü örneklem, part-time operatörlü sansürlü örneklem ve tam örneklem durumları için karşılaştırılmıştır, In this study, a new life testing method called “progressive type-I interval censoring with part time operator” is introduced. We obtained the maximum likelihood estimators for parameters of Weibull distribution. A simulation study is conducted to investigate the mean biases, mean variances and MSE (Mean Squared Error)'s of estimates. The results are compared for sampling progressive type-I interval censored data, part-time operator and complete data