Picosecond-precision multichannel autonomous time and frequency counter.

This paper presents the design, implementation, and test results of a multichannel time interval and frequency counter developed as a desktop instrument. The counter contains four main functional modules for (1) performing precise measurements, (2) controlling and fast data processing, (3) low-noise power suppling, and (4) supplying a stable reference clock (optional rubidium standard). A fundamental for the counter, the time interval measurement is based on time stamping combined with a period counting and in-period two-stage time interpolation that allows us to achieve wide measurement range (above 1 h), high precision (even better than 4.5 ps), and high measurement speed (up to 91.2 × 106 timestamps/s). The frequency is measured up to 3.0 GHz with the use of the reciprocal method. Wide functionality of the counter includes also the evaluation of frequency stability of clocks and oscillators (Allan deviation) and phase variation (time interval error, maximum time interval error, time deviation). The 8-channel measurement module is based on a field programmable gate array device, while the control unit involves a microcontroller with a high performance ARM-Cortex core. An efficient and user-friendly control of the counter is provided either locally, through the built-in keypad or/and color touch panel, or remotely, with the aid of USB, Ethernet, RS232C, or RS485 interfaces.

[Piracetam in severe cranio-cerebral injuries]. / Piracetam w ciezkich urazach czaszkowo-mózgowych.

A group of 100 patients treated immediately following a cranio-cerebral injury was analyzed. The patients, administered piracetam either in an intravenous infusion (GCS 3-8) or orally (GCS above 9), were divided into groups depending on the dose and clinical status. Piracetam participates in the activity of the majority of neurotransmitters, increases glucose and oxygen consumption in the ischaemic nervous tissue and increases blood flow through cerebral terminal vessels. In cranio-cerebral injuries, piracetam is employed to achieve cytoprotection and improve cerebral blood flow. In patients with neurological deterioration following the administration of 6-10 mg/day, no good results were obtained. A dose of 24-30 mg/day had a significant positive effect on therapeutic results providing certain conditions were met, such as ensuring proper partial oxygen pressure (oxygen therapy) and proper blood glucose levels. The use of piracetam is justified immediately after an injury; after the discharge oral piracetam therapy is recommended.

[Clinical observations concerning piracetam treatment of patients after craniocerebral injury]. / Spostrzezenia kliniczne leczenia nootropilem chorych po urazach czaszkowo-mózgowych.

Piracetam (Nootropil) is a cytoprotective to brain tissue and improving cerebral blood flow medicine. In the Department of Neurotraumatology we investigated results of piracetam treatment in a group of 100 succeeding patients admitted between 1995-96 due to craniocerebral injury. High doses (24-30 g per day) of this medicine have a positive effect on final result of treatment, when treatment is initiated immediately after the injury and described conditions are abided. We also showed usefulness of piracetam treatment in posthospital management.