Modelling the effect of sublethal injury on the distribution of the lag times of individual cells of Lactobacillus plantarum

The effect of heat stress on subsequent duration of the lag time of individual cells of Lactobacillus plantarum was analysed by flow cytometry. The results show clearly that both the mean and the standard deviation of the distribution of the lag time increased after sublethal heat treatment. The distributions of the lag times or the log lag times of untreated and treated cells, respectively, could be described as extreme value distributions. From these distributions, the distribution of the minimum lag times could be calculated and thus the effect of inoculum size on the apparent lag could be deduced. The results show clearly that the apparent lag time is dependent on the size of the inoculum, especially when the inoculum is sublethally injured.     

Self-sacrificial leadership and follower self-esteem: When collective identification matters.

In the present research, we examine whether leader's self-sacrifice positively influences followers' self-esteem and whether followers' identification with the collective plays a role in this process. It was predicted that leader self-sacrifice would influence followers' self-esteem, but particularly so when followers exhibited strong (vs. weak) collective identification. Results from an organizational survey showed that leader self-sacrifice and collective identification interacted in predicting follower self-esteem, such that followers' self-esteem was higher when they identified strongly with the collective and when the leader was self-sacrificial (vs. self-benefiting). An experimental scenario study replicated this interactive effect between collective identification and leader's self-sacrifice on followers' self-esteem and also showed that this effect was (at least partly) mediated by followers' perceptions of whether the leader respected and valued the group. Implications with respect to the relationship between self-sacrifice and self-esteem are outlined, and possible integrations of leader self-sacrifice, identity, and empowerment are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Traffic accident reduction by monitoring driver behaviour with in-car data recorders

People who are aware of being observed tend to modify their behaviour. This phenomenon could potentially be used to encourage individuals to behave more safely when driving if there were means of providing feedback to the drivers about their behaviour on the road. So-called 'vehicle data recorders' offer such a means of providing behavioural feedback by confronting drivers with their recorded driving actions. A field trial of a 'matched experimental/control group design with intervention' was planned with the objective of investigating whether this feedback mechanism would reduce the number of road traffic accidents in everyday driving conditions. In the study, seven experimental vehicle fleets were involved, which varied widely in terms of the kind of transport sector concerned, the type of vehicles used, and the traffic circumstances in which the vehicles are operated. Each fleet was matched with at least one control vehicle fleet, taking into account those relevant traffic safety characteristics. In total, accident and exposure data were collected for 840 vehicles of which 270 equipped with a recorder. During an observation period representing a total of about 3,100 vehicle years, these vehicles were involved in 1,836 road accidents. Analysis of the effects of the use of data recorders in these fleets resulted in an average estimated accident reduction of some 20%. The analysis shows that the actual savings vary depending on the transport sector involved and on the prior level of the fleet's safety record. Further studies are needed to identify the more promising application of such a use of traffic data recorders as a means of reducing road accidents.     

Laboratory investigation of the mass stability of sampling cassettes from inhalable aerosol samplers

A study was conducted to evaluate the mass stability of the materials used in the construction of samplers with internal cassettes for the gravimetric measurement of inhalable aerosol exposures. The internal cassettes from IOM samplers were studied. Results indicate that the mass stability of filters is uniform, but the mass stability of the cassette material may dramatically affect the results of the measurement. Cassettes constructed from plastic exhibited drastic shifts in mass depending on the environmental conditions of their storage. Under room humidity, the plastic cassettes absorbed 1 to 2 mg of water over several days. When these cassettes were placed in a desiccator, they lost mass consistently but did not approach a stable mass. Studies repeated with cassettes made of stainless steel showed negligible mass variability. Based on this study, the use of stainless steel cassettes is recommended for gravimetric determinations of aerosol exposure, although field blanks may in some cases be used for correction of data from plastic cassettes. This study shows the need to evaluate the mass stability of the cassette material of any sampling device where an internal cassette is weighed together with the filter.     

Discordance of databases designed for claims payment versus clinical information systems. Implications for outcomes research

OBJECTIVE: To determine the suitability of insurance claims information for use in clinical outcomes research in ischemic heart disease. DESIGN: Concordance study of two databases. SETTING: Tertiary care referral center. PATIENTS: A total of 12,937 consecutive patients hospitalized for cardiac catheterization for suspected ischemic heart disease between July 1985 and May 1990. INTERVENTIONS: Two-by-two tables were used to compute overall and kappa measures of agreement comparing clinical versus claims data for 12 important predictors of prognosis in patients with ischemic heart disease. MEASUREMENTS: Kappa statistics (agreement adjusted for chance agreement) were used to quantify agreement rates. RESULTS: Agreement rates between the clinical and claims databases ranged from 0.83 for the diagnosis of diabetes to 0.09 for the diagnosis of unstable angina (kappa values). Claims data failed to identify more than one half of the patients with prognostically important conditions, including mitral insufficiency, congestive heart failure, peripheral vascular disease, old myocardial infarction, hyperlipidemia, cerebrovascular disease, tobacco use, angina, and unstable angina, when compared with the clinical information system. CONCLUSIONS: Our results suggest that insurance claims data lack important diagnostic and prognostic information when compared with concurrently collected clinical data in the study of ischemic heart disease. Thus, insurance claims data are not as useful as clinical data for identifying clinically relevant patient groups and for adjusting for risk in outcome studies, such as analyses of hospital mortality.     

National surveillance of dialysis associated diseases in the United States, 1995

Many fundamental and hot band absorption lines of 28Si35Cl+, 28Si37Cl+, 29Si35Cl+, and 30Si35Cl+ have been detectedbetween 630 and 700 cm-1 in a SiCl4/He discharge using diode laser velocity modulation spectroscopy. The datahave been fitted to give seven mass independent coefficients Ukl. The derived spectroscopic constants for 28Si35Cl+ include omegae = 678.24316(18) cm-1 and Be = 0.2870288(14) cm-1. The equilibrium internuclear distance is re =1.9439105(46) ?. The equilibrium dissociation energy calculated from Dunham's expanded Morse potential is De =49 431(57) cm-1. Copyright 1998 Academic Press.     

Pediatric hepatic trauma: does clinical course support intensive care unit stay?

PURPOSE: The objective of this study is to determine if grade of liver injury predicts outcome after blunt hepatic trauma in children and to initiate analysis of current management practices to optimize resource utilization without compromising patient care. METHODS: A retrospective review of 36 children who had blunt hepatic trauma treated at a pediatric trauma center from 1989 to present was performed. Hepatic injuries graded (AAST Organ Injury Scaling) ranged from grade I to IV. Injury Severity Score (ISS), Glasgow Coma Score (GCS), transfusion requirements, liver transaminase levels, associated injuries, intensive care unit (ICU) length of stay, and survival were analyzed. RESULTS: Mean (+/-SEM) age was 6.6+/-0.8 years, mean grade of hepatic injury was 2.4+/-0.2, mean ISS was 17+/-2.6, mean GCS was 13+/-1, and mean transfusion was 15.4 mL/kg of packed red blood cells (PRBC). There were three deaths with a mean ISS of 59+/-9 and a mean GCS of 3+/-0. Death was not associated with a high-grade liver injury, survivors versus nonsurvivors, 2.3+/-0.2 versus 2.7+/-0.3, but was associated with ISS, 13+/-1.4 versus 59+/-9 (P = .005) and GCS, 14+/-1 versus 3+/-0 (P = .005). Only one patient (grade III, ISS = 43) underwent surgery. There were no differences in mean ISS or GCS between grades I to IV patients. The hepatic injury grades of patients requiring transfusion versus no transfusion were significantly different, 3.4+/-0.2 versus 2.2+/-0.2 (P = 0.04). Abused patients had high-grade hepatic injuries and significant laboratory and clinical findings. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were significantly higher in grade III and IV injuries than in grades I and II, 1,157+/-320 versus 333+/-61 (P= .02) and 1,176+/-299 versus 516+/-86 (P= .04), respectively. No children with grade I or II injury had a transfusion requirement or surgical intervention. There were no liver-related complications. CONCLUSIONS: Mortality and morbidity rates in pediatric liver injuries, grades I to IV, correlate with associated injuries not the degree of hepatic damage. ALT, AST, and transfusion requirements are significantly related to degree of liver injury. Low-grade and isolated high-grade liver injuries seldom require transfusion. Blunt liver trauma rarely requires surgical intervention. In retrospect, the need for expensive ICU observation for low-grade and isolated high-grade hepatic injuries is questionably warranted.     

Steady-state cerebral glucose concentrations and transport in the human brain

Understanding the mechanism of brain glucose transport across the blood-brain barrier is of importance to understanding brain energy metabolism. The specific kinetics of glucose transport have been generally described using standard Michaelis-Menten kinetics. These models predict that the steady-state glucose concentration approaches an upper limit in the human brain when the plasma glucose level is well above the Michaelis-Menten constant for half-maximal transport, Kt. In experiments where steady-state plasma glucose content was varied from 4 to 30 mM, the brain glucose level was a linear function of plasma glucose concentration. At plasma concentrations nearing 30 mM, the brain glucose level approached 9 mM, which was significantly higher than predicted from the previously reported Kt of approximately 4 mM (p < 0.05). The high brain glucose concentration measured in the human brain suggests that ablumenal brain glucose may compete with lumenal glucose for transport. We developed a model based on a reversible Michaelis-Menten kinetic formulation of unidirectional transport rates. Fitting this model to brain glucose level as a function of plasma glucose level gave a substantially lower Kt of 0.6 +/- 2.0 mM, which was consistent with the previously reported millimolar Km of GLUT-1 in erythrocyte model systems. Previously reported and reanalyzed quantification provided consistent kinetic parameters. We conclude that cerebral glucose transport is most consistently described when using reversible Michaelis-Menten kinetics.     

Synthesis and biological evaluation of certain new thiazolopyrimidines

A series of 5-methyl-3-phenyl thiazolo[5,4-e][1,2,4]triazolo[1,5-c] pyrimidin-2-thiones and 5-methyl-3-phenyl thiazolo[5,4-e]pyrimidino[3,4-b][1,2,4]triazin-2-thiones were prepared as potential antimicrobial and antitumor agents. Some of the tested compounds showed promising activity. The detailed synthesis, spectroscopic and biological data are reported.