Oxygen transport during extracorporeal oxygenation for the treatment of adult respiratory distress syndrome

An inventory of hemodynamic and respiratory measurements was obtained in two patients with acute respiratory failure syndrome prior to and during venoarterial extracorporeal membrane oxygenation for study of oxygen transport. As the inspired oxygen concentration fraction was reduced from 1.0 to 0.5 and paO2 was increased from less than 50 to physiologic ranges during extracorporeal membrane oxygenation, tachycardia and pulmonary hypertension were reversed. Total oxygen transport was reduced rather than increased. Oxygen consumption and oxygen extraction were not altered during extracorporeal membrane oxygenation. However, a striking reduction was observed in cardiac output. After reversal of anoxemia, the total of the cardiac output of the patient and the extracorporeal membrane oxygenation flow were less than the cardiac output of the patient prior to extracorporeal membrane oxygenation. These observations provide evidence that the beneficial effects of extracorporeal membrane oxygenation stem, at least in part, from a reduction of the work load on the heart. Since high cardiac output failure is observed during progression of adult respiratory distress syndrome, mechanical support of circulation during extracorporeal membrane oxygenation may be of primary therapeutic benefit.     

Analysis of donor versus nondonor demographics

A retrospective analysis of the demographic features of all potential organ donors over a 3-year period (1994-1996) at one organ procurement organization was conducted. The potential donor pool of 495 people was 42% female and 58% male, with a slight difference in consent by gender. The mean income difference between donors and nondonors was less than $3000 per year (obtained from zip code census data). Educational achievement affected donation at the lowest educational levels. Cause of death influenced donation, with motor vehicle crash victims donating more often. The strongest factor in consent for donation was ethnicity; whites were more likely to donate than were other ethnic groups. The combination of gender, ethnicity, and cause of death improved the probability of determining a positive outcome to 63%. Demographic information on donors and nondonors can increase public and professional understanding as well as influence decision making to improve donation.     

Temporal inferences by young children.

48 4–5 yr olds were taught to perform temporal operations with pairs of toys chosen from a set and tested with novel pairs of toys from the same set. For example, they might be taught to place Toy A through a trap door followed by Toy B, and Toy B followed by Toy C. Then they might be given the novel pair of Toys A and C to determine whether or not they make the transitive inference of placing A in the box before C. Results of 6 experiments show that Ss with little initial training made transitive temporal inferences of greater complexity than the transitive inference described above. Inferential strategies other than temporal transitivity, which were used by preoperational Ss when logical transitive inferences were impossible, were identified. These are discussed as the use of internal vs external serial boundaries. It is demonstrated how the methodology used in this study can be transformed into a test of children's linguistic competence. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term follow-up of ventriculoureteral shunts for treatment of hydrocephalus

We report on an 18-week fetus with cyclopia, alobar holoprosencephaly, complex congenital heart defect, anal atresia, oligosyndactyly, cystic hygroma, and skeletal abnormalities with trisomy 4. Structural anomalies were detected on routine ultrasound of the pregnancy of a 17-year-old G3 P1 TAB1 woman with sickle cell trait. Trisomy 4 conceptuses usually miscarry in the first trimester. We are aware of no other reports of a fetus with trisomy 4 and cyclopia. Causal association of chromosome abnormalities and holoprosencephaly sequence may be more apparent in embryos and early fetuses than term fetuses because of poor viability of affected conceptuses.     

Computer-aided manufacture of three-dimensional objects by laser space-resolved photopolymerization

The local absorption of the light of suitable energy can lead to the polymerization of a liquid monomer. By moving the incident laser beam, one can create objects of very fine quality. This idea is the basis for the computer-aided manufacture of three-dimensional objects.     

Performance of a two-junction array SIS-mixer operating around 345GHz

The authors have made a detailed study of the gain and noise of a SIS (superconductor-insulator-superconductor) heterodyne receiver at 345 GHz. An array of two Nb-Al₂O₃-Nb SIS junctions in series are used as the mixing element. The array is operated in a waveguide mount with a backshort and an E-plane tuner. The best receiver noise temperature achieved is 140 K DSB (double sideband). The embedding impedances were determined by fitting theory to the measured pumped curves. High-quality fits were obtained, providing the first detailed test of the Tucker-theory at frequencies above 300 GHz. The impedances found by this method are in very good agreement with impedances measured in a scale model at 3.3 GHz. From these embedding impedances, the gain and noise of the mixer were calculated over a full bias range using the Tucker theory in the three-port low-IF approximation. The measured dependence of mixer gain and noise on bias voltage, pump power and embedding impedance is in good agreement with theory. However the absolute values show discrepancies that appear to be independent of the bias parameters of the mixer     

Cognitive training in alcoholic men.

Three groups of alcoholic Ss (n?=?76) and one group of community nonalcoholic control subjects (n?=?36) were tested using a baseline battery of three clusters of neuropsychological tests measuring learning and memory, problem-solving, and perceptual-motor functioning. Alcoholics were divided into 3 groups: One group (n?=?25) received 12 hrs of memory training over the subsequent 2-wk period; a 2nd group (n?=?26) received a similar period of training in problem-solving techniques; and a 3rd group (n?=?25) received no training during the 2-wk period. Approximately 3 wks after the baseline testing, the same tests were readministered to the 3 groups. All 3 alcoholic groups performed significantly poorer than the control group on all 3 clusters of baseline tests but did not differ from each other on those clusters. At retest, the problem-solving group improved significantly more on the problem-solving tests than did the no-training group and manifested a trend to differ from the memory group but did not improve more than the other groups on memory or perceptual-motor tests. Although there was no overall differential improvement on memory tests by the memory-training group, younger Ss in that group improved significantly more than older Ss. This relation was not present in the other groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Implementation and evaluation of global and partitioned scheduling in a real-time OS

In this work, we provide an experimental comparison between Global-EDF and Partitioned-EDF, considering the run-time overhead of a real-time operating system (RTOS). Recent works have confirmed that OS implementation aspects, such as the choice of scheduling data structures and interrupt handling mechanisms, impact real-time schedulability as much as scheduling theoretic aspects. However, these studies used real-time patches applied into a general-purpose OS. By measuring the run-time overhead of an RTOS designed from scratch, we show how close the schedulability ratio of task sets is to the theoretical hard real-time schedulability tests. Moreover, we show how a well-designed object-oriented RTOS allows code reuse of scheduling components (e.g., thread, scheduling criteria, and schedulers) and easy real-time scheduling extensions. We compare our RTOS to a real-time patch for Linux in terms of the task set schedulability ratio of several generated task sets. In some cases, Global-EDF considering the overhead of the RTOS is superior to Partitioned-EDF considering the overhead of the patched Linux, which clearly shows how different OSs impact hard real-time schedulers.