Factors causing stress in patients in intensive care units

Intensive care units have been considered stress generating areas. Knowing the causes why this happens will allow us to take specific measures to prevent or minimize it. This study has been performed with the aim to identify stress raising factors, as they are perceived by intensive care patients. The study has been performed in 49 patients most of whom were being attended in postoperatory control. The valuation of the degree of stress was performed using the "Scale of Environmental Stressors in Intensive Care" by Ballard in 1981, modified and adapted to our environment, with a result of 43 items distributed in six groups; Immobilization, Isolation, Deprivation of sleep, Time-spacial disorientation, Sensorial deprivation and overestimulation, and depersonalization and loss of autocontrol. The level of stress perceived by patients was low. The factors considered as most stressing were those related to physical aspects; presence of tubes in nose and mouth, impossibility to sleep and presence of noise, whereas those less stressing referred to Nursing attention. We conclude that patients perceive ICU as a little stressing place in spite of the excessive noise, remark the presence of invasive tubes and the difficulty to sleep as the most stressing factors, and in the same way, express a high degree of satisfaction about the attention received.     

Innovative techniques in pediatric liver transplantation: reduced-, split- and living-donor related liver transplantation

BACKGROUND: Biological systems that show threshold phenomena are candidates for stochastic resonance as a mechanism to explain what appears to be biovariability. Stochastic resonance is the amplification of weak signals by "noise." OBJECTIVE: This review discusses the areas of contact dermatitis in which threshold events have been documented. The purpose is to point out the mechanism by which stochastic resonance may affect patch test results. METHODS: A literature review technique was used. RESULTS: The recent finding of a neurological influence on contract dermatitis provides a mechanism for stochastic resonance to affect patch test results. CONCLUSION: Stochastic resonance is likely to affect patch test results when more than one patch test result is positive.     

The lactulose breath hydrogen test and small intestinal bacterial overgrowth

OBJECTIVES: To i) document the sensitivity and specificity of a combined scintigraphic/lactulose breath hydrogen test for small intestinal bacterial overgrowth and ii) investigate the validity of currently accepted definitions of an abnormal lactulose breath hydrogen test based on "double peaks" in breath hydrogen concentrations. METHODS: Twenty-eight subjects were investigated with culture of proximal small intestinal aspirate and a 10-g lactulose breath hydrogen test combined with scintigraphy. Gastroduodenal pH, the presence or absence of gastric bacterial overgrowth, and the in vitro capability of overgrowth flora to ferment lactulose were determined. RESULTS: Sensitivity (16.7%) and specificity (70.0%) of the lactulose breath hydrogen test alone for small intestinal bacterial overgrowth were poor. Combination with scintigraphy resulted in 100% specificity, because double peaks in serial breath hydrogen concentrations may occur as a result of lactulose fermentation by cecal bacteria. Sensitivity increased to 38.9% with scintigraphy, because a single rise in breath hydrogen concentrations, commencing before the test meal reaches the cecum, may occur in this disorder. Sensitivity remained suboptimal irrespective of the definition of small intestinal bacterial overgrowth used, the nature of the overgrowth flora, favorable luminal pH, the presence of concurrent gastric bacterial overgrowth, or the in vitro ability of the overgrowth flora to ferment lactulose. CONCLUSIONS: Definitions of an abnormal lactulose breath hydrogen test based on the occurrence of double peaks in breath hydrogen concentrations are inappropriate. Not even the addition of scintigraphy renders this test a clinically useful alternative to culture of aspirate for diagnosing small intestinal bacterial overgrowth.     

An Experimental Economics Investigation of Shipper-carrier Interactions in the Choice of Mode and Shipment Size in Freight Transport

The paper discusses the theoretical and empirical evidence on the subject and concludes that freight mode choice can be best understood as the outcome of interactions between shippers and carriers, and that mode choice depends to a large extent on the shipment size that results from shipper-carrier interactions. These conclusions are supported by economic experiments designed to test the hypothesis of cooperative behavior. This was accomplished by conducting two sets of experiments (ones with the shipper playing the lead role in selecting the shipment size; and others in which the shipment size decision was left to the carriers), and by comparing their results to the ones obtained numerically under the assumption of perfect cooperation. The comparison of results indicated that the experiments converged to the perfect cooperation case. This is in line with the conclusion from game theory that indicates that under typical market conditions the shipper and carrier would cooperate. These results also imply that it really does not matter who “makes” the decision about the shipment size and mode to be used at a given time period, as over time the shipper—that is the customer—ends up selecting the bids more consistent with its own interest. In other words, these results do not support the assumption that freight mode choice is solely made by the carriers.     

Initial high beta operation of the HBT-EP Tokamak

HBT-EP is a new research tokamak designed and built to investigate passive and active feedback techniques to control MHD instabilities. In particular, HBT-EP will be able to test techniques to control fast MHD instabilities occurring at high Troyon-normalized beta, _N Ba/I_p [Tm/MA], since it is equipped with a thick, close-fitting, and adjustable conducting shell. The major goals of the initial operation of HBT-EP have been the achievement of high beta operation (_N 3) using only ohmic heating and the observation of MHD instabilities. By using a unique fast startup technique, we have successfully achieved these goals. A variety of MHD phenomena were observed during the high beta operation of HBT-EP. At modest beta (_N 2), discharges have been maintained for more than 10 msec, and these discharges exhibit saturated resistive instabilities. When _N approaches 3, major disruptions occur preceded by oscillating, growing precursors. During start-up, one or more minor disruptions are usually observed. A 1-D transport code has been used to simulate the evolution of the current profile, and these early minor instabilities are predicted to be double tearing modes. The simulation also reproduces the observed high beta operation when saturated neo-Alcator energy confinement scaling is assumed.     

Efficient worst-case data structures for range searching

In this paper we investigate the worst-case complexity of range searching: preprocess N points in k-space such that range queries can be answered quickly. A range query asks for all points with each coordinate in some range of values, and arises in many problems in statistics and data bases. We develop three different structures for range searching in this paper. The first structure has absolutely optimal query time (which we prove), but has very high preprocessing and storage costs. The second structure we present has logarithmic query time and O(N ¹⁺²) preprocessing and storage costs, for any fixed >0. Finally we give a structure with linear storage, O(N ln N) preprocessing and O(N ) query time.Research in this paper has been supported partially under Office of Naval Research contract N000014-76-C-0373, USA, and by the Austrian Federal Ministry for Science and Research     

On generators and generative capacity of EOL forms

Summary In this paper we study the generative capacity of EOL forms from two different points of view. On the one hand, we consider the generative capacity of special EOL forms which one could call linear like and context free like, establishing the existence of a rich variety of non-regular sub-EOL language families. On the other hand, we propose the notion of a generator L of a language family We mean by this that any synchronized EOL system generating L generates — if understood as an EOL form — all languages of . We characterize the generators of the family of regular languages, and prove that other well known language families do not have generators.Partially supported under NSE Research Council of Canada, grant No. A-7700     

Infant feeding practices in St. Vincent and factors which affect them

A survey was conducted in the summer of 1975 in 2 towns in St. Vincent--Layou and Georgetown--in the effort to obtain information regarding infant feeding practices and some of the factors which may influence them. Mothers of children from 1-2 years of age were interviewed in their homes. Complete data sets were obtained on 192 of the 216 eligible children in the 2 towns. For most children the period of exclusive breastfeeding (no other milk product given) was very short. About 1/2 of the children had received milk by 2 weeks of age, and 75% by 1 month. This was followed by a much longer period of "mixed" feeding--both breast and bottle--until breastfeeding was stopped at a median age of 6.8 months. Many types of milk were used for infant feeding. For 73% of the infants, infant formula was the 1st type of milk given. This was commonly replaced by a "heavier" full cream powdered milk at a few months of age. Prelacteal feeds were very common, predominantly glucose water. "Tonics," often consisting of vitamin preparations, were another common supplement during the early months of life. Among solid foods, arrowroot, "custard," and commercial infant cereals were the first to be introduced. Relatively inexpensive locally bagged staple foods and milk powders were available in both towns, but most mothers relied heavily on packaged brand name products for infant feeding even though the cost was 2-10 times higher. It was not possible to pinpoint the exact causes for the high levels of bottle feeding, nor for the possible recent decline in breastfeeding, but several important factors were identified. Part of the problem appeared to be due to poor health and nutritional status of the mothers. In addition, in several cases the mothers reported that they had wanted to continue breastfeeding but had received no support from health professionals, and in a few instances had been ordered to stop for seemingly trivial medical reasons.