N-(Dibenzylcarbamothioyl)-3-methylbutanamide: Crystal structure, Hirshfeld surfaces and antimicrobial activity

The compound N-(dibenzylcarbamothioyl)-3-methylbutanamide as a thiourea derivative was synthesized and structurally characterized by NMR and FT-IR spectroscopic techniques. The molecular structure of compound was also characterized by single crystal X-ray diffraction method. Crystal data for title compound C20H24N2OS: monoclinic, space group C2/c (no. 15), a = 19.6882(9) Å, b = 9.4045(4) Å, c = 19.5012(8) Å, β = 98.433(2)°, V = 3571.8(3) Å3, Z = 8, μ(CuKα) = 1.665 mm-1, 25057 reflections measured (9.168° ≤ 2Θ ≤ 144.196°), 3500 unique (Rint = 0.0322, Rsigma = 0.0200) which were used in all calculations. The final R1 was 0.0363 (I>2σ(I)) and wR2 was 0.0910 (all data). Intermolecular contacts obtained from X-ray single crystal diffraction study were also explored using both Hirshfeld surfaces and fingerprint plots. Hirshfeld surface analysis showed the occurrence of S···H, O···H and H···H contacts that display an important role to crystal packing stabilization of the thiourea derivative compound. In addition, the compound was evaluated for both their in-vitro antibacterial and antifungal activity

Carotid endarterectomy compared with carotid artery stenting for extracranial carotid artery stenosis: a retrospective single-centre study

Aim: One of the main risk factors for an ischemic stroke is significant carotid artery stenosis, and extracranial severe carotid artery stenosis accounts for 20% of ischemic strokes. Prior to the development of carotid artery stenting (CAS), the only effective and reliable treatment for carotid artery stenosis was carotid endarterectomy (CEA). This study compares the results of CAS and CEA in patients with significant carotid artery stenosis. Methods: Between 2018 and 2022, hospital records of all patients who underwent carotid artery revascularization at the institution were retrospectively analyzed. Patients were divided into two groups depending on whether CEA or CAS was performed for carotid revascularization. Propensity score matching was performed to reduce bias by equating the baseline clinical characteristics of the groups. To compare 30-day, 1-year, and long-term outcomes, rates of transient ischemic attack (TIA), myocardial infarction, stroke, all-cause mortality, and composite endpoints were analyzed. Results: After PSM, 76 patients each in the CEA and CAS groups were compared. The mean age was 69.80 years ± 11.35 years and 121 (80%) were male. The patients were followed up for a mean of 33 months ± 6 months. The incidence of TIA in the perioperative period [9 (12%) vs. 4 (5%); P < 0.05], TIA and composite endpoint at 1-year period [11 (15%) vs. 2 (3%); P < 0.05 and 27 (36%) vs. 16 (21%); P < 0.05, respectively] were significantly higher in the CAS group than in the CEA group. No difference was observed between the groups in the long-term. Conclusions: There was no noticeable difference between the CEA and CAS groups in the examination of cases with severe carotid artery stenosis in terms of 1-month, and 1-year results (apart from TIA and composite endpoints), or long-term outcomes. Extracranial carotid artery stenosis can be treated safely and effectively also by CAS

ÇİFT TARAFLI TİP II SANSÜRLENMİŞ ÖRNEKLEMLER İÇİN JONES VE FADDY’ NİN ÇARPIK t DAĞILIMININ KONUM VE ÖLÇEK PARAMETRELERİNİN TAHMİNİ

Bu çalışmada, çift taraflı Tip II sansürlenmiş (doubly Type II censored) örneklemler için Jones ve Faddy’ nin çarpık t (Jones and Faddy’ s Skew t - JFST) dağılımının konum ve ölçek parametrelerinin en çok olabilirlik (maximum likelihood - ML) ve uyarlanmış en çok olabilirlik (modified maximum likelihood - MML) tahmin edicileri elde edilmiştir. Monte Carlo (MC) simülasyon çalışması kullanılarak ML ve MML tahmin edicilerinin etkinlikleri karşılaştırılmıştır. MC simülasyon çalışması, MML tahmin edicilerinin ML tahmin edicileri ile hemen hemen aynı etkinliğe sahip olduğunu göstermiştir. Çalışma sonucunda, odaklanılan nokta tahmin edicilerin etkinlikleri ise ML tahmin edicilerinin, etkinlikle beraber hesaplama zorlukları ele alındığında ise MML tahmin edicilerinin tercih edilmesi gerektiği belirlenmiştir

Estimation and Testing in One-Way ANOVA when the Errors are Skew-Normal

We consider one-way analysis of variance (ANOVA) model when the error terms have skew- normal distribution. We obtain the estimators of the model parameters by using the maximum likelihood (ML) and the modified maximum likelihood (MML) methodologies (see, Tiku 1967). In the ML method, iteratively reweighting algorithm (IRA) is used to solve the likelihood equations. The MML approach is a non-iterative method used to obtain the explicit estimators of model parameters. We also propose new test statistics based on these estimators for testing the equality of treatment effects. Simulation results show that the proposed estimators and the tests based on them are more efficient and robust than the corresponding normal theory solutions. Also, real data is analysed to show the performance of the proposed estimators and the tests.Se considera el modelo de análisis de varianza a una vía (ANOVA) cuando los términos de error siguen una distribución normal sesgada. Se obtienen estimadores de los parámetros desconocidos mediante el uso de la metodología de máxima verosimilitud (ML). Se proponen nuevos estadísticos de prueba basados en estos estimadores. Los resultados de la simulación muestran que los estimadores propuestos y los tests basados en ellos son más eficientes y robustos que los correspondientes a las soluciones de la teoría normal. Un conjunto de datos real es analizado con el fin de mostrar el desempeño de los estimadores propuestos y sus tests relacionados

Estimation of the location and scale parameters of moyal distribution

In this study, we estimate the parameters of the Moyal distribution by using well-known and widely-used maximum likelihood (ML) and method of moments (MoM) methodologies. The ML estimators of the location and scale parameters of the Moyal distribution cannot be obtained in closed forms therefore iterative methods should be utilized. To make the study complete, modifed ML (MML) estimators for the location and the scale parameters of the Moyal distribution are also derived. The MML estimators are in closed forms and asymptotically equivalent to the ML estimators. Efficiencies of the MML estimators are compared with their ML and MoM counterparts using Monte-Carlo (MC) simulation study. Results of the simulation study show that the ML estimators are more efficient than the MML and MoM estimators for small sample sizes. However when the sample size increases performances of the ML and MML estimators are almost same in terms of the Defficiency (Def) criterion as expected. At the end of the study, a real data set is used to show the implementation of the methodology developed in this paper.Publisher's Versio

Alpha-Skew Generalized t Distribution

The alpha-skew normal (ASN) distribution has been proposed recently in the literature by using standard normal distribution and a skewing approach. Although ASN distribution is able to model both skew and bimodal data, it is shortcoming when data has thinner or thicker tails than normal. Therefore, we propose an alpha-skew generalized t (ASGT) by using the generalized t (GT) distribution and a new skewing procedure. From this point of view, ASGT can be seen as an alternative skew version of GT distribution. However, ASGT differs from the previous skew versions of GT distribution since it is able to model bimodal data sest as well as it nests most commonly used density functions. In this paper, moments and maximum likelihood estimation of the parameters of ASGT distribution are given. Skewness and kurtosis measures are derived based on the first four noncentral moments. The cumulative distribution function (cdf) of ASGT distribution is also obtained. In the application part of the study, two real life problems taken from the literature are modeled by using ASGT distribution.La distribución normal alfa-sesgada (ASN por sus siglas en inglés) ha sido propuesta recientemente en la literatura mediante el uso de una distribución normal estándar y procedimientos de sesgo. Aunque la distribución ASN es capaz de modelar tanto datos sesgados y bimodales, no es recomendada cuando los datos tienen colas más livianas o pesadas que la distribución normal. Por lo tanto, se propone una distribución t alfa-sesgada generalizada (ASGT por sus siglas en inglés) mediante el uso de la distribución t generalizada (GT por sus siglas en inglés) y un nuevo procedimiento de sesgo. Bajo este punto de vista, la distribución ASGT se puede ver como una alternativa sesgada de la distribución GT. Sin embargo, ASGT difiere de previas versiones sesgadas de la distribución GT puesto que es capaz de modelar datos bimodales y agrupa funciones de densidad más comúnmente usadas. En este artículo, los momentos y la estimación máximo verosímil de los parámetros de la distribución ASGT son derivadas. Medidas del sesgo y la curtosis son derivadas con base a los primeros cuatro momentos no centrales. La función de distribución acumulada (cdf por sus siglas en inglés) de la distribución ASGT es también obtenida. En la parte de aplicación del estudio, dos problemas reales tomados de la literatura son modelados usando la distribución ASGT

An alternative distribution to Weibull for modeling the wind speed data: Inverse Weibull distribution

Weibull distribution is widely used for modeling the wind speed data in literature. However, in real life, the wind speed data may not always be modeled by using the Weibull distribution. In other words, it may not represent all wind speed characteristic encountered in nature. Therefore, the alternative distributions are used in such cases. In this study, the Inverse Weibull (IW) distribution is used to model the wind speed. First, the modified maximum likelihood (MML) estimators of the parameters of IW distribution are obtained. Then the efficiencies of the MML estimators are compared with the well-known maximum likelihood (ML) and the least squares (LS) estimators via Monte-Carlo simulation study. Simulation results show that the LS estimators are the least efficient among the others. Finally, Weibull and IW distributions are used for modeling the seasonal wind speed data sets obtained from the Turkish State Meteorological Service. It is shown that IW distribution based on the ML and the MML estimates of the parameters provides better modeling than the Weibull distribution based on the corresponding estimates in most of the cases. The suitability of these distributions is compared with respect to root mean square error (RMSE) and coefficient of determination (R-2) criteria

N-(Dibenzylcarbamothioyl)-3-methylbutanamide: Crystal structure, Hirshfeld surfaces and antimicrobial activity

The compound N-(dibenzylcarbamothioyl)-3-methylbutanamide as a thiourea derivative was synthesized and structurally characterized by NMR and FT-IR spectroscopic techniques. The molecular structure of compound was also characterized by single crystal X-ray diffraction method. Crystal data for title compound C20H24N2OS: monoclinic, space group C2/c (no. 15), a = 19.6882(9) Å, b = 9.4045(4) Å, c = 19.5012(8) Å, β = 98.433(2)°, V = 3571.8(3) Å3, Z = 8, μ(CuKα) = 1.665 mm-1, 25057 reflections measured (9.168° ≤ 2Θ ≤ 144.196°), 3500 unique (Rint = 0.0322, Rsigma = 0.0200) which were used in all calculations. The final R1 was 0.0363 (I>2σ(I)) and wR2 was 0.0910 (all data). Intermolecular contacts obtained from X-ray single crystal diffraction study were also explored using both Hirshfeld surfaces and fingerprint plots. Hirshfeld surface analysis showed the occurrence of S···H, O···H and H···H contacts that display an important role to crystal packing stabilization of the thiourea derivative compound. In addition, the compound was evaluated for both their in-vitro antibacterial and antifungal activity

The value of NT-pro-brain natriuretic peptide and left ventricular ejection fraction for prediction of premature ventricular complexes burden

OBJECTIVE: We aimed to investigate the relation of NT-pro BNP level and left ventricular ejection fraction with premature ventricular complex burden. PATIENTS AND METHODS: A total of 94 patients with PVC burden > 5% (age 45.9+12.9 years, 53 males, 41 females) were included in the study. The primary outcome was PVC burden % and main prognostic factors were LVEF% and NT-Pro BNP level. Gender, age, DM, HTN, presence of symptoms, symptom duration and heart rate were used as adjustment predictor variables. We created four different linear multivariable models to compare performance measures of prognostic factors: Model-1 has gender, age, DM, HTN, symptoms and heart rate, while LVEF has been added in addition to model-1 in model-2. Model-3 included NT-Pro-BNP alongside model-1 variables, while model-4 included both LVEF and NT-Pro-BNP variables in addition to model-1 variables. Accordingly, we compare the performance (R2, likelihood ratio X2) of models. RESULTS: The median PVC burden was 18% (IQR; 11-27). When model-1 consisting of gender, age, DM, HTN, presence of symptoms, symptomS duration and heart rate and model-2 consisting of LVEF in addition to variables of model-1 were compared, it was observed that both LRX2 and R2 values improved (likelihood ratio test p-value=0.013). Model-1 compared with model-3 which consisting of NT-pro BNP in addition to variables of model-1, and it was observed that both LRX2 and R2 values improved (likelihood ratio test p-value=0.008). However, when compared to model-1, the most significant improvement was observed in both LRX2 and R2 values in model-4 consisting of model-1 plus NT-Pro-BNP and LVEF (likelihood ratio test p-value <0.001). CONCLUSIONS: We determined that NT-pro-BNP levels and LVEF could predict PVC burden in patients. Higher levels of NT-pro-BNP and lower LVEF values were associated with increased PVC burden