Anemia increases gastric blood flow in noncirrhotic and cirrhotic patients

BACKGROUND: Previous studies in rats have demonstrated that anemia induces a significant increment in gastric mucosal blood flow. In the present study, we investigated whether chronic anemia induces similar changes in gastric blood perfusion in humans, and if this effect is also present in cirrhotic patients in whom gastric blood flow is usually increased in basal conditions. METHODS: Gastric mucosal blood perfusion was assessed by means of laser-Doppler flowmetry and reflectance spectrophotometry applied through the endoscope. RESULTS: Anemia significantly increases laser-Doppler signal in cirrhotic (2.3 +/- 0.11 vs 2.9 +/- 0.22 volts, p < 0.05) and noncirrhotic patients (1.71 +/- 0.15 vs 2.24 +/- 0.17, p < 0.05). In anemic patients the index of hemoglobin concentration of the gastric mucosa, assessed by reflectance spectrophotometry, was significantly decreased in cirrhotic patients (107.6 +/- 4.7 vs 95.5 +/- 3.3, p < 0.05) and noncirrhotic patients (93.9 +/- 4.1 vs 76.1 +/- 4.2, p < 0.01), whereas the index of oxygen saturation was increased (36.7 +/- 0.7 vs 40.4 +/- 1.4, p = 0.05; and 36.4 +/- 1.1 vs 43.2 +/- 1.9, p < 0.01, respectively). CONCLUSIONS: In conclusion, chronic anemia is associated with an enhanced gastric blood perfusion reflected by an increased laser-doppler signal and gastric mucosal oxygen index despite a decrease in gastric hemoglobin concentration. In cirrhotic patients, anemia promotes a further increment in its basal gastric hyperemia.     

Quantifying the role of risk-taking behaviour in causation of serious road crash-related injury

This study was designed to quantify the increased risk of road crash-related injury, which can be attributed to risk-taking behaviour. A case-control study was conducted to compare motor vehicle drivers (car and bike) who had been hospitalised for injuries following crashes with population-based controls. Cases were recruited prospectively over 12 months and controls were randomly selected from license holders (car and bike) living in the same geographical location as cases. A self-administered questionnaire was used to ascertain participants' driving behaviour, general risk-taking behaviour and selected demographic characteristics. After adjusting for demographic variables, number of years of driving and total distance driven per week, logistic regression analysis showed that a high risk acceptance was associated with an eight-fold increased risk of having a crash that resulted in serious injury (OR 7.8, 95% CI 4.2-15.8). The findings of this study support the suggestion that certain host factors increase the risk of crash-related serious injury. There would appear to be a reasonable argument for persisting with injury prevention programmes, which concentrate on host as well as environment risk factor reduction.     

Characterizing user navigation through complex data structures

As part of the general study of user navigation through interactive databases, a set of indices is proposed to characterise users' search sequences. These indices are presented as an attempt to capture some of the psychologically significant aspects of the movement of users within interactive data-bases. An example of the use of the indices is given in reference to an experiment to compare front-ends to a data-base program. Their strengths and weaknesses are discussed in the light of this experiment. Their potential as a basis for the precise definition of search strategies such as browsing and scanning is also considered.     

A longitudinal examination of computer self-efficacy change trajectories during training

Computer self-efficacy (CSE) is known to enhance individual competence and performance in learning and using technology as well as improve technology attitudes and beliefs. Using longitudinal studies, CSE increases over time during organizational technology training. While these studies have been instrumental in our understanding of how self-efficacy operates in organizations, some critical questions remain unanswered. In particular these studies cannot answer how long it takes for one’s CSE to increase during training, nor can it describe the shape of the change trajectory (linear? some other shape?). The answers to these questions will provide organizations a much clearer perspective on training expectations, understanding when benefits from training through enhanced CSE might be expected, and when to start and ramp up/down training efforts. This study examines these issues by collecting repeated waves of data from 230 respondents in a technology lab training setting and using a relatively new structural equation modeling technique, latent growth modeling. Findings suggest that it takes about 2 months of training for individuals to display significant increases in CSE, and that the growth trajectory for CSE in non-linear. In the proposed model, anxiety is a significant predictor of CSE change, while CSE change significantly predicted software-specific self-efficacies.     

Quantitation of Lamb Content in Mixtures with Raw Minced Beef Using Visible, Near and Mid-Infrared Spectroscopy

Samples of beef (32), lamb (33) and 5%, 10% and 20% (w/w) lamb-in-beef mixtures (33 each) were minced and reflectance scanned in the visible, near and mid-infrared spectral regions. Partial least squares (PLS) regression models were developed to predict percentage lamb content using each spectral region alone and combinations of all three. The most accurate models combined mid-IR (800-2000 cm^-1) and near IR (1100-2498 nm) spectral data following 2^nd derivatization; standard errors of prediction of 0.91% (0–20% range in lamb content) and 4.1% (0–100% range in lamb) were obtained. This technique may be useful for screening such meat mixtures.     

Lockout energy control placarding for power distribution equipment

The use of lockout techniques is required in most facilities, including power distribution facilities, but is often established in many different ways. Often times flags, tags, the instructions of a system operator, or other means are utilized in power distribution facilities to approximate the same level of safety is afforded by use of actual physical locks. Extensive training is required to maintain the integrity of these alternate systems, but the chance of error is greater than in the systems where locks are used. Use of personal locks also squarely places the responsibility of achieving the electrically safe condition of the equipment upon the worker or employee. The tool discussed in this article, called a placard, has been used in some industrial facilities to enhance the federal requirements of a lockout energy control program. This tool has been applied to power distribution equipment. This article discusses the development and implementation of placards along with the advantages and difficulties encountered during the process     

Christopher Strachey—Understanding Programming Languages

Higher-Order and Symbolic Computation -     

The feasibility of a mixed reality surgical training environment

The Sheffield knee arthroscopy training system (SKATS) was originally a visual-based virtual environment without haptic feedback, but has been further developed as a mixed reality-training environment through the use of tactile augmentation (or passive haptics). The design of the new system is outlined and then tested. In the first experiment described, the effect of tactile augmentation on performance is considered by comparing novice performance using the original and mixed reality system. In the second experiment the mixed reality system is assessed in terms of construct validity by comparing the performance of users with differing levels of surgical expertise. The results are discussed in terms of the validity of a mixed reality environment for training knee arthroscopy.     

天钢高线厂加热炉控制系统的升级改造

介绍了天钢高线厂采用SIEMENS公司SIMATIC WINCC、S7-300监控系统代替L&N公司的MICROMAXII系统对加热炉进行控制,解决了由于L&N公司倒闭而带来的备件问题。目前系统运行良好。