Damage Mechanisms in Medium-Voltage Insulating Polymers under Hemispherical-Plane Electrodes

International audienceControlling the lifetime of insulating materials is required to insure reliability of insulation systems for Medium Voltage (MV) and High Voltage (HV) cables. The aging behavior of Low Density (LDPE) and Cross-Linked Polyethylene (XLPE) under MV-AC thermo-electric stress is studied in the sphereplane geometry in air to identify degradation mechanisms associated to Corona Discharges (CDs) and their impact on insulation lifetime. Times to breakdown values are measured under different applied electric fields. Additionally, XLPE samples are aged to different ageing steps. Then, the samples are analyzed by scanning electron microscopy and infrared spectroscopy to monitor progressive damage during ageing

Limits of early diagnosis of herpes simplex encephalitis in children: a retrospective study of 38 cases.

The prognosis of herpes simplex encephalitis (HSE) depends on the early and appropriate administration of specific antiviral therapy. We retrospectively reviewed 38 cases of children with proven HSE, to evaluate the reliability of polymerase chain reaction results, according to the time of cerebrospinal fluid (CSF) sampling. Initial negative results were observed in 8 of 33 CSF samples drawn before day 3 of the disease and were significantly associated with a low level of protein and <10 leukocytes/mm3 in the CSF.Journal Articleinfo:eu-repo/semantics/publishe