Survey of management of first-ever seizures in a hospital based community.

Epidemiological studies focusing on first-ever seizures have been carried out mainly on community based populations. However, since hospital populations may display varying clinical features, we prospectively analysed patients with first-ever seizure in a hospital based community to evaluate prognosis and the role of complementary investigations in the decision to administer antiepileptic drugs (AED). Over one year, we recruited 177 consecutive adult patients with a first seizure acutely evaluated in our hospital. During six months' follow-up data relating to AED treatment, recurrence of seizures and death were collected for each patient. Neurological examination was abnormal in 72.3%, neuroimaging in 54.8% and biochemical tests in 57.1%. Electroencephalogram (EEG) showed epileptiform features in 33.9%. Toxicity represented the most common aetiology. AED was prescribed in 51% of patients. Seizure recurrence at six months involved 31.6% of patients completing the follow-up; mortality was 17.8%. Statistical analysis showed that brain CT, EEG and neurological examination are independent predictive factors for AED administration, but only CT scan is associated with outcome. Patients evaluated acutely for first-ever seizure in a hospital setting have severe underlying clinical conditions apparently related to their relatively poor prognosis. Neuroimaging represents the most important paraclinical test in predicting both treatment administration and outcome

Start-up of a Varspeed Group in Pump Mode, Practical Implementations and Tests

The present paper addresses the practical implementation in a test bench of different control strategies for the start-up of a varspeed group in pump mode. In varspeed groups using a double-fed induction machine supplied by back to back voltage source inverters (VSI), the possibility exists of using the rotor side VSI to start up the group. The current paper focuses on the start-up strategy and its implementation in a test bench of 3.3 kVA. After presenting the hardware composing the test bench, two different start-up strategies are detailed, which are the field oriented control and critical torque. Those two strategies are then implemented in practice, tested, measured and compared

A stator flux oriented vector control for induction motor drives

The present paper describes a stator flux oriented control strategy using state space controllers. The optimal determination of different controllers'parameters (suitable placement of poles, continuous adapation of coefficients to the operating point of the drive) leads to an independent control of the stator flux and the torque in different operating conditions, and consequently to good dynamic performances of the drive. The effectiveness of the proposed system is verified by computer simulation. The control implementation on a Motorola DSP 56002 is in progress

Mixed signal simulation applied to modern adjustable speed drives.

The paper deals with the main problems to solve in order to simulate precisely the behavior of complex power systems with mixed elements (power components and digital regulation devices). A simulation tool developed at the Swiss Federal Institute of Technology is shortly described. Finally, an industrial application of an induction motor fed by a three-level inverter tuned with a DTC (Direct Torque Control) is presented

Mixed signal simulation in the field of adjustable speed drives.

The paper deals with the main problems to solve in order to simulate precisely the behavior of complex power systems with mixed elements (power components and digital regulation devices). The main features of an efficient simulation tool are described. They are focused on modern adjustable speed drives. Finally, the simulation of an industrial application of an induction motor fed by a three-level inverter tuned with a DTC (Direct Torque Control) is presented in details

Vector Control of an Induction Machine in a Stator Flux Reference Frame.

This paper describes a stator flux oriented control strategy using state space controllers. The optimal determination of the different controllers parameters leads to an independent control of the stator flux and the torque. The effects of undesired offsets on the calculated stator flux are discussed and a solution for eliminating these offset is presented Verification by computer simulation and results of the control implementation on a Motorola DSP 56002 are presente

Increasing Wind Power Penetration in Autonomous Power Systems through No-Flow Operation of Pelton Turbines

The integration of wind power in power systems results in a reduction in greenhouse gas emissions. Thus, it has a positive environmental impact. However, the operation of these power systems becomes increasingly complex, owing mainly to random behaviour of the wind

The Four Different Types of Internal Hernia Occurring After Laparascopic Roux-en-Y Gastric Bypass Performed for Morbid Obesity: Are There Any Multidetector Computed Tomography (MDCT) Features Permitting Their Distinction?

BACKGROUND: Four different types of internal hernias (IH) are known to occur after laparoscopic Roux-en-Y gastric bypass (LRYGBP) performed for morbid obesity. We evaluate multidetector row helical computed tomography (MDCT) features for their differentiation. METHODS: From a prospectively collected database including 349 patients with LRYGBP, 34 acutely symptomatic patients (28 women, mean age 32.6), operated on for IH immediately after undergoing MDCT, were selected. Surgery confirmed 4 (11.6%) patients with transmesocolic, 10 (29.4%) with Petersen's, 15 (44.2%) with mesojejunal, and 5 (14.8%) with jejunojejunal IH. In consensus, 2 radiologists analyzed 13 MDCT features to distinguish the four types of IH. Statistical significance was calculated (p < 0.05, Fisher's exact test, chi-square test). RESULTS: MDCT features of small bowel obstruction (SBO) (n = 25, 73.5%), volvulus (n = 22, 64.7%), or a cluster of small bowel loops (SBL) (n = 27, 79.4%) were inconsistently present and overlapped between the four IH. The following features allowed for IH differentiation: left upper quadrant clustered small bowel loops (p < 0.0001) and a mesocolic hernial orifice (p = 0.0003) suggested transmesocolic IH. SBL abutting onto the left abdominal wall (p = 0.0021) and left abdominal shift of the superior mesenteric vessels (SMV) (p = 0.0045) suggested Petersen's hernia. The SMV predominantly shifted towards the right anterior abdominal wall in mesojejunal hernia (p = 0.0033). Location of the hernial orifice near the distal anastomosis (p = 0.0431) and jejunojejunal suture widening (p = 0.0005) indicated jejunojejunal hernia. CONCLUSIONS: None of the four IH seems associated with a higher risk of SBO. Certain MDCT features, such as the position of clustered SBL and hernial orifice, help distinguish between the four IH and may permit straightforward surgery

Survey of management of first-ever seizures in a hospital based community

BACKGROUND: Epidemiological studies focusing on first-ever seizures have been carried out mainly on community based populations. However, since hospital populations may display varying clinical features, we prospectively analysed patients with first-ever seizure in a hospital based community to evaluate prognosis and the role of complementary investigations in the decision to administer antiepileptic drugs (AED). METHODS: Over one year, we recruited 177 consecutive adult patients with a first seizure acutely evaluated in our hospital. During six months' follow-up data relating to AED treatment, recurrence of seizures and death were collected for each patient. RESULTS: Neurological examination was abnormal in 72.3%, neuroimaging in 54.8% and biochemical tests in 57.1%. Electroencephalogram (EEG) showed epileptiform features in 33.9%. Toxicity represented the most common aetiology. AED was prescribed in 51% of patients. Seizure recurrence at six months involved 31.6% of patients completing the follow-up; mortality was 17.8%. Statistical analysis showed that brain CT, EEG and neurological examination are independent predictive factors for AED administration, but only CT scan is associated with outcome. CONCLUSIONS: Patients evaluated acutely for first-ever seizure in a hospital setting have severe underlying clinical conditions apparently related to their relatively poor prognosis. Neuroimaging represents the most important paraclinical test in predicting both treatment administration and outcome