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Rock slope stability is almost controlled by the behaviour of the interface between rock layers. The presence of shale layers between limestone layers complicates this behaviour. As the shale layer undergoes swelling with moisture, it causes the shear interface properties to change with a specific behaviour different from the dry state. The behaviour will depend on the shale’s degree of saturation, swelling percentage, and stress level over shale. An experimental program was carried out to determine the shear interface behaviour parameters of shale-limestone during swelling phenomena to guide stability checks. The interface cohesion and friction angle results are reported along the swelling process and compared with the dry state condition. These results help engineers assign adequate and accurate values for joint shear and normal stiffness in jointed rock slopes, including swelling layers., Stabilnost stijenskih kosina uglavnom je uvjetovana interakcijom kontaktne površine između slojeva stijenske mase. Prisutnost slojeva šejla između slojeva vapnenca usložnjava tu situaciju. Kako sloj šejla bubri zbog vlage, dolazi do promjene svojstava kontaktne površine koja se specifično razlikuje od suhoga stanja. Ponašanje će ovisiti o stupnju zasićenosti šejla, postotku bubrenja i veličini naprezanja u materijalu iznad šejla. Provedeno je eksperimentalno ispitivanje za određivanje parametara ponašanja smicanja kontaktne površine šejla i vapnenca tijekom pojave bubrenja te je provedena provjera stabilnosti. Vrijednosti kohezije i kuta unutarnjega trenja na kontaktnim površinama opažane su tijekom procesa bubrenja i uspoređivane su s vrijednostima suhoga stanja. Ti rezultati pomažu inženjerima odabrati odgovarajuće i pouzdane vrijednosti smične i normalne krutosti za diskontinuirane stijenske kosine na kojima se pojavljuju slojevi koji bubre.

Pediatric stroke is relatively uncommon, with often subtle clinical presentations. Numerous predisposing risk factors can be both inherited and acquired, including cardiac disease, vascular abnormalities, infectious diseases, collagen tissue diseases, inborn errors of metabolism, anticardiolipin antibody, lupus anticoagulant, deficiencies of protein C, protein S, antithrombin, or plasminogen, and prothrombotic mutations. We explored risk factors, clinical features, and neuroimaging among Egyptian children with ischemic stroke, and estimated the prevalence of inherited thrombophilia. We included 20 children with ischemic stroke, recruited from the Pediatric Neurology Outpatient Clinic (Ain Shams University). Basic clinical evaluations for stroke and genotyping for factor V 1691 G-A (factor V Leiden), prothrombin 20210 G-A mutations, and methylenetetrahydrofolate reductase 677 C-T polymorphisms were performed using real-time polymerase chain reaction, with fluorescent melting curve detection analysis. Ten patients (50%) manifested methylenetetrahydrofolate reductase polymorphisms (six homozygotes and four heterozygotes). Heterozygous factor V Leiden was present in five (25%), whereas prothrombin mutation was present in only one (5%). Five patients (25%) manifested combined prothrombotic abnormalities. Thirteen demonstrated evidence of inherited thrombophilic disorder; 25% manifested more than one mutation. For appropriate risk assessment, even in the presence of overt acquired thrombotic risk factors, physicians should request complete thrombophilia screening for patients with stroke. (C) 2012 Elsevier Inc. All rights reserved.

Pediatric stroke is relatively uncommon, with often subtle clinical presentations. Numerous predisposing risk factors can be both inherited and acquired, including cardiac disease, vascular abnormalities, infectious diseases, collagen tissue diseases, inborn errors of metabolism, anticardiolipin antibody, lupus anticoagulant, deficiencies of protein C, protein S, antithrombin, or plasminogen, and prothrombotic mutations. We explored risk factors, clinical features, and neuroimaging among Egyptian children with ischemic stroke, and estimated the prevalence of inherited thrombophilia. We included 20 children with ischemic stroke, recruited from the Pediatric Neurology Outpatient Clinic (Ain Shams University). Basic clinical evaluations for stroke and genotyping for factor V 1691 G-A (factor V Leiden), prothrombin 20210 G-A mutations, and methylenetetrahydrofolate reductase 677 C-T polymorphisms were performed using real-time polymerase chain reaction, with fluorescent melting curve detection analysis. Ten patients (50%) manifested methylenetetrahydrofolate reductase polymorphisms (six homozygotes and four heterozygotes). Heterozygous factor V Leiden was present in five (25%), whereas prothrombin mutation was present in only one (5%). Five patients (25%) manifested combined prothrombotic abnormalities. Thirteen demonstrated evidence of inherited thrombophilic disorder; 25% manifested more than one mutation. For appropriate risk assessment, even in the presence of overt acquired thrombotic risk factors, physicians should request complete thrombophilia screening for patients with stroke. (C) 2012 Elsevier Inc. All rights reserved.