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Boron nitride (BN) reinforced Al6061 aluminum-based composites are synthesized by conventional stir casting method followed by exposure to hot extrusion. The optical images confirmed the distribution of BN nanoparticles in the aluminum alloy matrix. The concentration of BN is varied from (0.5, 1.5, 3, 4.5, 6, 7.5, and 9 wt%) in the composites and its effect on the tensile strength was investigated. The results revealed that both extruded and heat-treated composites specimens showed enhanced toughness an tensile strength by increasing BN nanoparticle concentration. The heat-treated composite samples showed lower flexibility of up to 40%, and further, it exhibited 37% greater hardness and 32% enhancement in tensile strength over the extruded sample. The tensile properties of Al6061-BN composites were evaluated by temperature-dependent internal friction (TDIF) analysis and the results showed that the as-prepared composite's strength increased with temperature.. [ABSTRACT FROM AUTHOR]

Purpose: To compute diagnostic test properties of C-reactive protein (CRP) and serum procalcitonin (PCT) levels in bloodstream infections in children with cancer and suspected sepsis, in comparison with blood culture as the gold standard., Methodology: Consecutive paediatric cancer patients, aged ≤14 years, with clinically suspected bloodstream infections were evaluated with blood culture and assay of PCT and CRP levels. Blood culture was taken as the gold standard for comparison. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), likelihood ratio (LR) and receiver operating characteristic (ROC) with area under ROC curve (AUC) were calculated to assess the diagnostic test performance for PCT and CRP.Results/Key findings. The ROC curve for PCT was better than that for CRP, with an AUC of 0.751 for PCT at a cut-off of 2.25 ng ml-1. The AUC for CRP was 0.638 at a cut-off of 8.0 mg dl-1. Among the three cut-off values of PCT selected from the ROC curve applicable to the patients under study, the cut-off value of ≥0.49 ng ml-1 had the maximum sensitivity of 81.4 % and an NPV of 94.67 %; ≥2.25 ng ml-1 had a sensitivity and specificity of 65.12 and 71.6 %, respectively, and ≥6.47 ng ml-1 had a maximum specificity of 82.10 %. For CRP, the cut-off value of ≥5.3 mg dl-1 had the maximum sensitivity of 72.09 %; ≥8.0 mg dl-1 had a sensitivity and specificity of 58.14 and 68.09 %, respectively, and ≥8.4 mg dl-1 had the maximum specificity of 70.04 %., Conclusion: PCT is a better serological marker for excluding bloodstream infections than CRP. The cut-off value of 0.49 ng ml-1 with a negative predictive value of 94.67 % will be ideal in a clinical setting of immune-compromised children with suspected sepsis.

A case of paratesticular papillary serous cystadenocarcinoma in a six year old child is presented. The occurrence of these epithelial tumours of the ovarian type, in the paratesticular region is extremely rare and only six cases have been reported so far. They are thought to arise from Mullerian metaplasia of the peritoneal lining of the tunica vaginalis, appendix testis or mullerian remnants between the testis and spermatic cord.