Is FLT3 internal tandem duplication an unfavorable risk factor for high risk children with acute myeloid leukemia? : Polish experience

According to the AML-BFM 2004 Interim, a treatment protocol used in Poland since 2005, presence of FLT3 internal tandem duplication (FLT3/ITD) qualifies a patient with acute myeloid leukemia (AML) to a high-risk group (HRG). The present study was aimed to identify the prevalence of FLT3/ITD in children with AML in Poland and to evaluate its prognostic significance in the HRG patients. Out of 291 children with de novo AML treated in 14 Polish centers between January 2006 and December 2012, samples from 174 patients were available for FLT3/ITD analysis. Among study patients 108 children (61.7%) were qualified to HRG. Genomic DNA samples from bone marrow were tested for identification of FLT3/ITD mutation by PCR amplification of exon 14 and 15 of FLT3 gene. Clinical features and treatment outcome in patients with and without FLT3/ITD were analyzed in the study. The FLT3/ITD was found in 14 (12.9%) of 108 HRG children. There were no significant differences between children with and without FLT3/ITD in age and FAB distribution. The white blood cells count in peripheral blood at diagnosis was significantly higher (p <0.01) in the children with FLT3/ITD. Over 5-year overall survival rate for FLT3/ITD positive children was worse (42.4%) comparing to FLT3/ITD negative children (58.9%), but the statistical difference was not significant. However, over 5-year survivals free from treatment failures were similar. The FLT3/ITD rate (12.9%) observed in the study corresponded to the published data. There was no significant impact of FLT3/ITD mutation on survival rates, although further studies are needed on this subject

Semi-Empirical Topological Method for Prediction of the Relative Retention Time of Polychlorinated Biphenyl Congeners on 18 Different HR GC Columns

High resolution gas chromatographic relative retention time (HRGC-RRT) models were developed to predict relative retention times of the 209 individual polychlorinated biphenyls (PCBs) congeners. To estimate and predict the HRGC-RRT values of all PCBs on 18 different stationary phases, a multiple linear regression equation of the form RRT = ao + a1 (no. o-Cl) + a2 (no. m-Cl) + a3 (no. p-Cl) + a4 (VM or SM) was used. Molecular descriptors in the models included the number of ortho-, meta-, and para-chlorine substituents (no. o-Cl, m-Cl and p-Cl, respectively), the semi-empirically calculated molecular volume (VM), and the molecular surface area (SM). By means of the final variable selection method, four optimal semi-empirical descriptors were selected to develop a QSRR model for the prediction of RRT in PCBs with a correlation coefficient between 0.9272 and 0.9928 and a leave-one-out cross-validation correlation coefficient between 0.9230 and 0.9924 on each stationary phase. The root mean squares errors over different 18 stationary phases are within the range of 0.0108–0.0335. The accuracy of all the developed models were investigated using cross-validation leave-one-out (LOO), Y-randomization, external validation through an odd–even number and division of the entire data set into training and test sets

A Novel Methodology Using Simplified Approaches for Identification of Cracks in Beams

Abstract In this paper, natural frequency based forward and inverse methods are proposed for identifying multiple cracks in beams. Forward methods include simplified definition of the natural frequency drops caused by the cracks. The ratios between natural frequencies obtained from multi-cracked and un-cracked beams are determined by an approach that uses the local flexibility model of cracks. This approach does not consider nonlinear crack effects that can be easily neglected when the number of cracks is not excessive. In addition, an expression, which removes the necessity of repeating natural frequency analyses, is given for identifying the connection between the crack depths and natural frequency drops. These simplified approaches play crucial role in solving inverse problem using constituted crack detection methodology. Solution needs a number of measured modal frequency knowledge two times more than the number of cracks to be detected. Efficiencies of the methods are verified using the natural frequency ratios obtained by the finite element package. The crack detection methodology is also validated using some experimental natural frequency ratios given in current literature. Results show that the locations and depths ratios of cracks are successfully predicted by using the methods presented

Diagnostic Value of Lysozyme Activity Estimation in the Feces of Infants with Acute Diarrhoea

Peer Reviewe

Test losowości mechanicznych systemów transakcyjnych

Wielu inwestorów używa mechanicznych systemów transakcyjnych. Systemy takie testowane są na danych historycznych, gdzie osiągają dobre wyniki. W artykule tym opisano metodę testowania systemów transakcyjnych opartą na hipotezie, iż system podejmuje decyzje losowo. Przy założeniu prawdziwości hipotezy konstruowany jest odpowiedni system losowy, który z takimi samymi prawdopodobieństwami generuje sygnały zajęcia pozycji. Opisywany system zajmuje pozycję długą (zakłada wzrost cen) bądź krótką (zakłada spadek cen) na kontraktach futures na indeks S&P500 (system zawsze posiada pozycję, nigdy nie jest poza rynkiem). Obliczenia dla systemu losowego wykonywane są wiele razy i tworzony jest rozkład prawdopodobieństwa wyników systemu. W oparciu o uzyskany rozkład weryfikowana jest hipoteza o losowości testowanego systemu.Many traders use mechanical systems to trade. Such trading systems usually are tested on historical data. It shows good performance in the past. This paper describes the method for evaluating such trading systems based on the hypothesis that the tested system is trading randomly [1]. Under this null hypothesis we build a random system of the same characteristics as the tested one. The random system presents the same probabilities of taking a long position (betting on the price going up) and taking a short position (betting on the price going down) as tested system. The only distinguishing factor is the performance of the system. Simulations of the random system are run many times to create a performance distribution that is used to verify the null hypothesis. The test system in this paper trades the S&P500 futures from January 2003 until September 2008, taking always either long or short positions (always in the market) and reinvesting the profits