Phthalazine derivatives attached to amino acid derivatives were synthesized with high yields. The reaction of phthalazine derivatives with different phthalyl and tosylamino acids such as glycine, alanine, phenylalanine, valine, serine, and threonine in the presence of N,N-dicyclo hexylcarbodiimide (DCC) as a dehydrating agent reagent yielded high yields of the afforded compounds.Phthalylamino acids derivatives were obtained by deprotection of phthalazine derivatives, with the latter heating with hydrazine hydrate. The chemical structures of all phthalazine derivatives were affirmed by elemental analysis and spectral data (IR, MS, 1 HNMR, and 13 C NMR). Screening out and estimation of the synthesized derivatives for their cytotoxic and antioxidant activity were done, and most of them showed powerful activity in comparison with standard drugs.We got all chemical reagents from Sigma-Aldrich. Solvents were purchased from El-Nasr Chemicals in analytical grade. Also, we did thin-layer chromatography (TLC) on all products by using silica gel polyester sheets (Kieselgel 60 F254, 0.20 mm, Merck). All melting points are in degree centigrade (uncorrected). We recorded IR spectra (KBr) at the Microanalytical Center (Faculty of S C H E M E 1 Synthesis of phthalazinone derivative 2 S C H E M E 2 Synthesis of phthalazines derivative (4,5) WASFY ET AL.

Finite mixture models have been used in many fields of statistical analysis such as pattern recognition, clustering and survival analysis, and have been extensively applied in different scientific areas such as marketing, economics, medicine, genetics and social sciences. Introducing mixtures of new generalized lifetime distributions that exhibit important hazard shapes is a major field of research aiming at fitting and analyzing a wider variety of data sets. The main objective of this article is to present a full mathematical study of the properties of the new finite mixture of the three-parameter Weibull extension model, considered as a generalization of the standard Weibull distribution. The new proposed mixture model exhibits a bathtub-shaped hazard rate among other important shapes in reliability applications. We analytically prove the identifiability of the new mixture and investigate its mathematical properties and hazard rate function. Maximum likelihood estimation of the model parameters is considered. The Kolmogrov-Smirnov test statistic is used to fit two famous data sets from mechanical engineering to the proposed model, the Aarset data and the Meeker and Escobar datasets. Results show that the two-component version of the proposed mixture is a superior fit compared to various lifetime distributions, either one-component or two-component lifetime distributions. The new proposed mixture is a significant statistical tool to study lifetime data sets in numerous fields of study.

Context: Post-dural headache puncture (PDPH) is a frequent consequence after lumbar puncture. PDPH usually has frontal/occipital, postural headaches that are worse while they are standing and better when they are resting. Symptoms associated with stiff neck, loss of hearing, tinnitus, photophobia and nausea. The prevalence of PDPH in pregnant women is greater. This research seeks to examine the latest update on the prevention of post-dural headache puncture for pregnant women in the caesarean section. Methods: The search in MEDLINE, Embase, Pubmed and CINAHL Plus was conducted in the same periodical with the following mediacl terms: "post-dural; cramp; headache; caesarean section," encompassing articles 2000-2020, 2012; Articles other than English are excluded from the review. Results and findings: Headache treatment after accidental hard puncture varies. This diversity extends to the literature with various PDPHA definitions and epidural blood patch indications. More importantly, the absence of follow-up of the patients following accidental dural puncture was a survey addressed to members of the Society for Obstetric Anesthesia and Perinatology. Due to contradictory facts and views, a documented procedure is essential and all departmental members have to be followed.