One of the most important problems in communication network design is the stability of network after any disruption of stations or links. Since a network can be modeled by a graph, this concept is examined under the view of vulnerability of graphs. There are many vulnerability measures that were defined in this sense. In recent years, measures have been defined over some vertices or edges having specific properties. These measures can be considered to be a second type of measures. Here we define a new measure of the second type called the total accessibility. This measure is based on accessible sets of a graph. In our study we give the total accessibility number of well known graph models such as Pn, Cn, Km,n, W1,n, K1,n. We also examine this new measure under operations on graphs. A simple algorithm, which calculates the total accessibility number of graphs, is given. We observe that when any two graphs of the same size are compared in stability, it is inferred that the graph of higher total accessibility number is more stable than the other one. All the graphs considered in this paper are undirected, loopless and connected.
The objective of our study was to assess the influence of mechanical ventilation on healthy body organs. Fifteen piglets (aged 6 weeks, 19-27 kg) were anesthetized, instrumented, and divided into three groups: Group A - spontaneously breathing, group B - mechanically ventilated with tidal volume 6 ml/kg, and group C - ventilated with tidal volume 10 ml/kg for 12 hours. The parameters of lung, heart, liver and kidney functions neurohumoral regulation and systemic inflammatory reaction were recorded initially (time-1) and after 12 hours (time-12) of mechanical ventilation. At the onset of experiment (time-1) the levels of soluble adhesive molecules were higher (CAM; P<0.01), glomerular filtration index and free water clearance were lower (P<0.05) in both ventilated groups than in group A. Right ventricle myocardial performance index was higher (RIMP; P<0.05) in group C when compared with group A. Levels of CAM (P<0.05) and creatinine clearance (P<0.01) were higher, free water clearance was lower (P<0.05) in group C when compared to group B. At time-12 the RIMP (P<0.05) and levels of CAM were increased (P<0.01), creatinine clearance was decreased (P<0.05) in both ventilated groups compared to the same parameter at time-1. Ventilation index was higher (P<0.05), and hypoxemic index was lower (P<0.01) in group C when compared to group B. In conclusion, this study showed that mechanical ventilation induced changes compatible with early inflammatory response in healthy animals. Higher tidal volumes had detrimental effect on ventilatory parameters, reduced myocardial performance and potentiated adverse reaction of other organs., J. Kobr ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Total carotenoids assessed spectrophotometrically in crude extracts may be considerably overestimated when high contents of phenolic compounds are co-extracted. In this case, the absorbance tails of phenolics extend well into the blue part of the spectrum, interfering with carotenoid estimation. Extracts of phenolic-rich organs, with a low ratio of photosynthetic to heterotrophic and/or supportive cells (for example, stems or twigs) are vulnerable to such pitfalls and may need chromatographic separation of carotenoids. and E. Levizou, Y. Petropoulou, Y. Manetas.
The aim of this study is to evaluate the results of total hip arthroplasty in patients with Parkinson's disease during a period of five years, focusing on the assessment of the risks and benefits of surgery. During this period we performed total hip arthroplasty in 14 patients (15 hips) with Parkinson's disease. Patients were evaluated by subjective symptoms and objective findings, with a focus on the use of support while walking and walking distance, severity of Parkinson's disease before surgery and at the time of the last follow-up. During the postoperative period, the following parameters were assessed: length of ICU stay, mobilization, complications, the total duration of hospitalization and follow-up care after discharge. Of the 11 patients (12 hips) followed-up 1-5 years with an average of 3 years after operation 8 cases showed progression of neurological disability. 5 patients (6 hips) showed an increased dependence on the use of support when walking and reduced distance that the patient was able to walk. Subjectively, 10 hip joints were completely painless and 2 patients complained of only occasional mild pain in the operated hip. Complications that were encountered were urinary tract infection (5 patients), cognitive impairment (3 patients) and pressure ulcer (2 patients). We did not observe any infection or dislocation of the prosthesis. Three patients fell and fractured the femur and 3 patients in our cohort died during follow up. Implantation of total replacement is possible with judicious indication after careful evaluation of neurological finding in patients with minimal or mild functional impairment of the locomotor system. Prerequisite for a good result is precise surgical technique and optimal implant position with balanced tension of the muscles and other soft tissues around the hip. and PG. Mathew, P. Sponer, T. Kucera, M. Grinac, J. Knízek