Implantable Drainage After Major Abdominal Surgery in Compromised Patients

The risk of superinfection following routine abdominal drainage after major surgery is debated. Especially in patients with malignant diseases and a compromised host defense, this might be a factor increasing morbidity and mortality. During a 3-year period (1986–1988) 41 patients operated on for malignant abdominal conditions received a peritoneal catheter connected to a subcutaneous portal inserted in order to participate in a trial on postoperative intraperitoneal chemotherapy using 5- Fluorouracil. No abdominal drains were inserted. In 15 patients, the subcutaneous portal was used for evacuation of postoperative fluid accumulation within the abdomen. The mean age was 53 (range 41–70) years. Inserted catheters were used for drainage up to 14 days postoperatively. The daily amount of fluid drained varied from 20 to 2 000 ml with a mean of 610 ml/patient and day. One patient required removal of the catheter due to infection around the subcutaneous chamber. Otherwise, the catheter system was not associated with any other complications or complaints. One patient developed a postoperative left subphrenic abscess drained percutaneously by the guidance of ultrasonography, a complication that could not be attributed to the catheter system but merely to the major operation per se. An implantable device for peritoneal access thus also seem useful for drainage of postoperative fluid collection, as evaluated in this preliminary report

Anticipatory Modeling and Simulation for Inter Regional Security

Peer reviewe

Gender differences in the physiological responses and kinematic behaviour of elite sprint cross-country skiers

Gender differences in performance by elite endurance athletes, including runners, track cyclists and speed skaters, have been shown to be approximately 12%. The present study was designed to examine gender differences in physiological responses and kinematics associated with sprint cross-country skiing. Eight male and eight female elite sprint cross-country skiers, matched for performance, carried out a submaximal test, a test of maximal aerobic capacity (VO2max) and a shorter test of maximal treadmill speed (Vmax) during treadmill roller skiing utilizing the G3 skating technique. The men attained 17% higher speeds during both the VO2max and the Vmax tests (P < 0.05 in both cases), differences that were reduced to 9% upon normalization for fat-free body mass. Furthermore, the men exhibited 14 and 7% higher VO2max relative to total and fat-free body mass, respectively (P < 0.05 in both cases). The gross efficiency was similar for both gender groups. At the same absolute speed, men employed 11% longer cycles at lower rates, and at peak speed, 21% longer cycle lengths (P < 0.05 in all cases). The current study documents approximately 5% larger gender differences in performance and VO2max than those reported for comparable endurance sports. These differences reflect primarily the higher VO2max and lower percentage of body fat in men, since no gender differences in the ability to convert metabolic rate into work rate and speed were observed. With regards to kinematics, the gender difference in performance was explained by cycle length, not by cycle rate

Analysis of a sprint ski race and associated laboratory determinants of world-class performance

This investigation was designed to analyze the time-trial (STT) in an international cross-country skiing sprint skating competition for (1) overall STT performance and relative contributions of time spent in different sections of terrain, (2) work rate and kinematics on uphill terrain, and (3) relationships to physiological and kinematic parameters while treadmill roller ski skating. Total time and times in nine different sections of terrain by 12 world-class male sprint skiers were determined, along with work rate and kinematics for one specific uphill section. In addition, peak oxygen uptake (VO2peak), gross efficiency (GE), peak speed (Vpeak), and kinematics in skating were measured. Times on the last two uphill and two final flat sections were correlated to overall STT performance (r = ~−0.80, P < 0.001). For the selected uphill section, speed was correlated to cycle length (r = −0.75, P < 0.01) and the estimated work rate was approximately 160% of peak aerobic power. VO2peak, GE, Vpeak, and peak cycle length were all correlated to STT performance (r = ~−0.85, P < 0.001). More specifically, VO2peak and GE were correlated to the last two uphill and two final flat section times, whereas Vpeak and peak cycle length were correlated to times in all uphill, flat, and curved sections except for the initial section (r = ~−0.80, P < 0.01). Performances on uphill and flat terrain in the latter part were the most significant determinants of overall STT performance. Peak oxygen uptake, efficiency, peak speed, and peak cycle length were strongly correlated to overall STT performance, as well as to performance in different sections of the race

Self-Adapting Parameters in Simulation of Management Systems

peer reviewedThis paper deals with a new version of a web-based software simulation tool MLD-STAR (Management Learning and Decision making – Simulation Tool with Anticipation and Retardation), for the numerical simulation of mathematical models of management systems. A new algorithm is presented to automatically compute the numerical values of the parameters of models to be simulated. The main idea consists in generating successive sets of values of the parameters of the model with a random number generator, and to use a selection criterion for accepting or rejecting the sets of values. This self-adapting parameters method is so based on a Darwinian process of selection. Results of simulations with such self-adapting parameters are given in using the mathematical model given in Dubois and Holmberg (2006)

Anticipatory Artificial Autopoiesis

peer reviewedIn examining relationships between autopoiesis and anticipation in artificial life (Alife) systems it is demonstrated that anticipation may increase efficiency and viability in artificial autopoietic living systems. This paper, firstly, gives a review of the Varela et al [1974] automata algorithm of an autopoietic living cell. Some problems in this algorithm must be corrected. Secondly, a new and original anticipatory artificial autopoiesis algorithm for automata is presented. In our automata system, the asymmetric membrane of the self-creating living cell plays a central role. The simulation confirms the validity of our algorithm in showing its autopoietic properties

Dewatering and Drying of Bark

Technical solutions for a number of Swedish industrial installations for dewatering and drying of bark are compiled and discussed. Further, lab-scale experiments with a heated bark pressing process have been performed to investigate to what extent parameters such as temperature and pressure will influence the dewatering process. Pressing with a heated press at 150 °C was shown to increase the dewatering by over 20 % and more efficient dewatering is expected if the bark is more evenly heated before the press. In the drying area rotary and superheated steam dryers are replaced with bed dryers mainly due to the fact that the drying air can be heated with low-grade energy sources and that the maintenance costs are lower. The economy for such a process will to a very large extent depend on using waste energy sources at the mill which can be considered at no or very low cost