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Special Device (special + device)
Selected AbstractsPhysical model of the interference immunity of electronic devices and conclusions concerning their testing and operating characteristicsEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 3 2000H. Bauer Switching and fault processes in power-supply systems cause pulse-shaped disturbances which may stress electronic devices of protection and control systems. For test purposes such disturbances can be simulated. But despite of the constant test conditions the reaction of the device on the disturbance can vary in a certain range. Assuming similar internal structures of protection and control devices the coupling path and the effects of the disturbance are described. The variation in device reaction due to the disturbance is explained on the basis of different models which imitate the impact of the disturbances especially on the logical part of the circuit. By applying sensors with constant threshold the effectiveness (function) of several EMC measures can be evaluated independently from the reaction of the special device. [source] Unravelling the microbial role in ooid formation , results of an in situ experiment in modern freshwater Lake Geneva in SwitzerlandGEOBIOLOGY, Issue 4 2008K. PLEE ABSTRACT The microbial role in the formation of the cortex of low-Mg calcite freshwater ooids in western part of Lake Geneva in Switzerland has been suggested previously, but not demonstrated conclusively. Early work mostly concentrated in hypersaline milieus, and hence little is known about their genesis in freshwater environments. We designed an in situ experiment to mimic the natural process of low-Mg calcite precipitation. A special device was placed in the ooid-rich bank of the lake. It contained frosted glass (SiO2) slides, while quartz (SiO2) is the most abundant mineral composition of ooid nuclei that acted as artificial substrates to favour microbial colonization. Microscopic inspection of the slides revealed a clear seasonal pattern of carbonate precipitates, which were always closely associated with biofilms that developed on the surface of the frosted slides containing extracellular polymeric substance, coccoid and filamentous cyanobacteria, diatoms and heterotrophic bacteria. Carbonate precipitation peaks during early spring and late summer, and low-Mg calcite crystals mostly occur in close association with filamentous and coccoid cyanobacteria (e.g. Tolypothrix, Oscillatoria and Synechococcus, Anacystis, respectively). Further scanning electron microscope inspection of the samples revealed low-Mg calcite with crystal forms varying from anhedral to euhedral rhombohedra, depending on the seasons. Liquid cultures corroborate the in situ observations and demonstrate that under the same physicochemical conditions the absence of biofilms prevents the precipitation of low-Mg calcite crystals. These results illustrate that biofilms play a substantial role in low-Mg calcite ooid cortex formation. It further demonstrates the involvement of microbes in the early stages of ooid development. Combined with ongoing microbial cultures under laboratory-controlled conditions, the outcome of our investigation favoured the hypothesis of external microbial precipitation of low-Mg calcite as the main mechanism involved in the early stage of ooid formation in freshwater Lake Geneva. [source] The effects of exercise during hemodialysis on adequacyHEMODIALYSIS INTERNATIONAL, Issue 1 2005C. Caner Pedalling during hemodialysis (HD) has been shown to increase solute clearance in a previous study. In the present study, we aimed to test whether an easy to perform exercise program, not requiring a special device, could yield similar outcomes. Fifteen HD patients with the mean age of 48.4 ± 3.8 years were enrolled into the study. Patients with significant access recirculation (>10%), moderate to severe coronary artery disease, moderate to severe heart failure, severe chronic obstructive lung disease, and history of lower extremity surgery during last three month period were excluded. All patients were studied on two consecutive HD sessions with identical prescriptions. At the first session, standard HD was applied without exercise, whereas in the second session lower extremity exercise of 30 minutes duration was added. Reduction rates and rebound for urea, creatinine, and potassium and Kt/V were calculated. Wilcoxon signed rank test was applied in analysis and p < 0.05 was accepted as significance level. All patients completed the study. When both sessions were compared, mean arterial blood pressure (97 ± 3 mmHg vs 120 ± 4 mmHg, p < 0.001) and heart rate (77 ± 1 beats/min vs 92 ± 3 beats/min, p < 0.001) were higher in the exercise group. On the other hand, urea reduction rates, rebound values of urea, creatinine, and potassium were similar in both groups. Conclusion:,In the study, we did not observe any changes in solute rebound and clearance with the exercise. Shorter duration of the exercise may be the explanation of failure to achieve desired outcomes. Increasing patients' tolerance and fitness levels by means of steadily increasing exercise programs may be of help. Additionally, mode of exercise may also be responsible for different outcomes. [source] Prognosis of stage I pressure ulcers and related factorsINTERNATIONAL WOUND JOURNAL, Issue 4 2006Miwa Sato Abstract The prognosis of stage I pressure ulcers cannot be predicted; therefore, nursing interventions for preventing their deterioration have not been clearly established. This study describes the clinical course of stage I pressure ulcers and prospectively investigates the factors related to their deterioration. Thirty-one stage I pressure ulcers in 30 patients in a long-term care facility were studied, and morphological changes were assessed every day until the ulcers healed or deteriorated. The physiological changes were assessed by ultrasonography and thermography. Twenty ulcers healed, and 11 deteriorated. The characteristics of deterioration were as follows: (1) double erythema; (2) non blanchable erythema across the whole area determined by glass plate compression; (3) erythema away from the tip of the bony prominence; and (4) expanding erythema on the following day. We analysed the sensitivity, specificity, positive predictive value, negative predictive value and positive likelihood ratio for the diagnostic utility of the indicators of deterioration double erythema and distance from the tip of bony prominence, which can be instantly assessed without the use of any special device. The values were 36·4%, 95·0%, 80·0%, 73·1% and 7·28, respectively. These results suggest that clinicians can predict the prognosis of stage I pressure ulcers by initial assessment and provide appropriate care based on the assessment. [source] Transumbilical laparoscopic urological surgery: are special devices strictly necessary?BJU INTERNATIONAL, Issue 8 2009Anibal W. Branco OBJECTIVE To evaluate the safety and feasibility of transumbilical laparoscopic surgery using conventional laparoscopic instruments and ports. PATIENTS AND METHODS Since January 2008 we have been using laparoscopic transumbilical procedures. Patient selection was determined by any situation, pathological or not, for which laparoscopy was deemed appropriate as the standard of care in our practice. Exclusion criteria included patients who had undergone multiple abdominal procedures. The Veress needle was placed through the umbilicus, to allow insufflation with carbon dioxide. A 10-mm trocar was placed in the peri-umbilical site for the laparoscope, followed by placing two additional 5-mm peri-umbilical trocars. The entire procedure was done using conventional laparoscopic instruments. At the end of surgery the trocars were removed and all three peri-umbilical skin incisions were united for specimen retrieval. Patients undergoing surgery using this approach were evaluated prospectively and data were collected during and after surgery for analysis. RESULTS Six procedures were performed using this technique (three nephrectomies, one adrenalectomy, one ureterolithotomy and one retroperitoneal mass resection). The mean operative duration and blood loss were 70.5 min and 108.3 mL, respectively. There were no complications during surgery and no patients needed a blood transfusion. Analgesia comprised metamizole (1 g intravenous every 6 h) and ketoprofen (100 mg intravenous every 12 h). The time to first oral intake was 8 h and the mean hospital stay was 28 h. CONCLUSION Laparoscopic transumbilical surgery seems to be feasible and safe even using conventional laparoscopic instruments, and can be considered a potential alternative for traditional laparoscopic urological procedures. [source] | ||||||||||