Strategic failure in social interaction: Evidence for expectancy disconfirmation processes.

Two experiments were conducted to test the idea that individuals may fail strategically in order to lower the expectations that others hold for their performances. In a pilot study, participants reported that, when lacking confidence, they would be particularly uncomfortable and anxious with high expectations and would attempt to lower them strategically. In Experiment 1, socially anxious and nonanxious participants were led to believe that an interviewer's high or low expectations were due to a prodigious amount of effort or to very little effort. Socially anxious individuals tended to fail strategically when confronted with high as opposed to low expectations presumably based on a prodigious amount of previous effort. In Experiment 2, individuals high or low in social anxiety were led to believe that an interviewer held either high or low expectations for them. High-anxiety participants, led to believe their initial performance would affect high expections, showed much poorer initial performance relative to all other groups. These findings show that individuals who are particularly doubtful about their ability to perform up to par will sometimes fail strategically at the outset of social interaction as a means to create lower and safer standards. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Performance of advanced resuscitation skills by pediatric housestaff

OBJECTIVE: To describe pediatric housestaff resuscitation experience and their ability to perform key resuscitation skills. DESIGN: Cohort study of 63 pediatric residents in a university-based training program. PARTICIPANTS AND METHODS: Investigators observed, scored, and timed resident performance on 4 key resuscitation skills. Cognitive ability was tested with 4 written scenarios. Housestaff provided self-reports of the number of months since their last American Heart Association Pediatric Advanced Life Support course, number of mock and actual codes attended, number of times skills were performed, and self-confidence with respect to resuscitation. RESULTS: A total of 45 pediatric residents (71%) participated. Median cognitive score was 5 (range, 1-5). Of all residents, 44 (97%) successfully bag mask-ventilated the mannequin; 24 (53%) and 36 (80%) used the correct bag and mask size, respectively. Thirty-nine residents (87%) placed a tube in the mannequin trachea, 12 (27%) checked that suction was working prior to intubation, and 30 (67%) chose the correct endotracheal tube size. Forty residents (89%) discharged the defibrillator, and 25 (56%) and 32 (71%) correctly chose asynchronous mode and infant paddles, respectively. Thirty-eight residents (84%) inserted an intraosseous line; 35 (78%) had correct placement. Median times for successful skill completion were 83 seconds for bag mask ventilation, 136 seconds for intubation, 149 seconds for defibrillation, and 68 seconds for intraosseous line placement. CONCLUSION: Pediatric housestaff previously trained in pediatric advanced life support were generally able to reach the end point of 4 key resuscitation skills but less frequently performed the specific subcomponents of each skill. This poor performance and the prolonged time to skill completion suggest the need for greater attention to detail during training.     

Symptomatic hamartoma of the spinal cord associated with neurofibromatosis type 1. Case report

The authors present a case in which a symptomatic hamartoma was found in the spinal cord of a patient with neurofibromatosis type 1 (NF-1). This 52-year-old woman presented with painful urinary incontinence. Magnetic resonance (MR) imaging revealed an intramedullary lesion within the lower thoracic spinal cord and conus medullaris, which was surgically removed. Pathological investigation showed a hamartomatous lesion consisting of glial cells, ganglion cells, abundant disoriented axons, and thin-walled vessels. This case provides a pathological correlate to the hamartomatous lesions demonstrated on MR imaging in patients with NF-1 and illustrates that these benign lesions may become symptomatic and require neurosurgical intervention.     

Varietal Differentiation of Grape Juice Based on the Analysis of Near- and Mid-infrared Spectral Data

The aim of this study was to evaluate the usefulness of visible (VIS), near-infrared reflectance (NIR) and mid-infrared (MIR) spectroscopy combined with pattern recognition methods as tools to differentiate grape juice samples from commercial Australian Chardonnay (n = 121) and Riesling (n = 91) varieties. Principal component analysis (PCA), partial least squares discriminant analysis and linear discriminant analysis (LDA) were applied to classified grape juice samples according to variety based on both NIR and MIR spectra using full cross-validation (leave-one-out) as a validation method. Overall, LDA models correctly classify 86% and 80% of the grape juice samples according to variety using MIR and VIS-NIR, respectively. The results from this study demonstrated that spectral differences exist between the juice samples from different varietal origins and confirmed that the infrared (IR) spectrum contains information able to discriminate among samples. Furthermore, analysis and interpretation of the eigenvectors from the PCA models developed verified that the IR spectrum of the grape juice has enough information to allow the prediction of the variety. These results also suggested that IR spectroscopy coupled with pattern recognition methods holds the necessary information for a successful classification of juice samples of different varieties.     

A method for defining competency in Pediatrics

In 1972 the American Board of Pediatrics (ABP) initiated studies leading to a report which identifies the important components of competency needed in the practice of pediatrics. The development of the report involved a group process engaging ABP board members and examiners. The outcome has been (a) the delineation of a process for establishing definitions of competency in a medical discipline; (b) the development of a framework for specifying the abilities needed to perform the tasks required of pediatricians; (c) an elaboration of samples of pediatric subjects to which these abilities and tasks are relevant; and (d) the development of a basis for choice of methods to use for purposes of certification.     

Advances in ventricular synchronous demand cardiac pacemakers

New ventricular synchronous demand (VVT) pacemaker functions have been developed that provide improved performance in electromagnetic interference (EMI) environments and improved sensing of ventricular premature contractions. All previous ventricular synchronous pacemakers had an inherent design conflict between choosing the optimal (relatively long) input refractory interval needed for limiting the maximum pulse delivery rate and choosing the optimal (relatively short) input refractory interval (sensing dead time) following either a sensed or paced cardiac contraction. The necessary compromise resulted in a device that in the presence of EMI, stimulated at a rate (approximately 150 ppm) which was dangerously fast for certain patients, yet was insensitive to early poststimulation (400 to 500 msec) premature ventricular contractions, resulting in a risk of T-wave stimulation. Partly because of these deficiencies, the VVT function has not been widely employed by the medical profession: instead, the ventricular inhibited (VVI) pacemaker has evolved as the treatment of choice for the cardiac patient with intermittent heart block, even though total inhibition by certain EMI radiators is a potentially serious problem. New VVT structures have been developed that allow control separation of the maximum EMI discharge rate and the sensing refractory interval by employing independent input and output refractory intervals. New low-power digital devices provide building blocks applicable to the developed architectures.     

Prospects for gene therapy of haemophilia A and B

Haemophilia A and B are relatively rare, X-linked inherited bleeding disorders which are life-threatening to patients unless treated by regular injections of factors VIII or IX, respectively. Gene therapy offers the prospect of a cure for the disease, thus potentially freeing patients from the existing regimens of regular intravenous injection of proteins and the risks of infection by contaminating viruses. Although, in theory, gene therapy is very attractive to patients and clinicians, in practice, preclinical experiments in animal models suggests that it may be difficult to obtain adequate therapeutic levels of either factors VIII or IX for long periods of time in patients unless improved methods can be devised. Progress in the preclinical studies is more encouraging with haemophilia B than with haemophilia A. Clinical trials for haemophilia B patients have started in China.     

Rechargeable silver-modified mercuric oxide-zinc cell for cardiac pacemakers

Tests were conducted on rechargeable mercury-zinc pacemaker batteries under simulated and actual biologic conditions, using a variety of discharge rates and charging schedules. In tests on 96 cells at a 6.4 milliampere (ma) discharge, recharging once every 15 months of simulated pacing at a 25 microampere (mua) drain, the earliest cell failure occurred after an equivalent of 50 years of pacing. The mean pacing equivalent for all 96 cells was more than 140 years. In 6.4 ma discharge tests on 24 cells, recharging once every 8 days of simulated pacing, only 1 cell in 24 failed after an equivalent of more than 500 years of pacing (actual time 2 years). In tests on 13 cells pacing at a 200 mua drain without recharging, the simulated mean duration of pacing before total discharge was 4.8 years. Seven other cells at a 200 mua drain with periodic recharging continue to function normally after more than 7 years of actual time, simulating 56 years of pacing at a 25 mua drain. Cardiac pacemakers using the rechargeable mercury-zinc cell have been implanted in animals for more than 2 1/2 years and in patients for more than 1 year with all units continuing to function satisfactorily. It has been demonstrated unequivocally that a rechargeable mercury-zinc pacemaker will function continuously for more than 4 years without recharging and that periodic recharging will extend pacing life far beyond that predicted for lithium and nuclear primary power sources.     

New Interference Sensing Demand Pacemaker Functions

Demand cardiac pacemaker functions are under study that provide new methods to distinguish between cardiac activity and pulsatile electromagnetic interference (PEMI). All known forms of currently marketed ventricular inhibited demand pacemaker (VVI) functions can be inhibited by high level pulsatile electromagnetic interference. The recent introduction of shielded circuitry to protect against disruptive (inhibiting) EMI has reduced pacemaker sensitivity to interference. However, EMI received via the cardiac lead/electrode can still mimic cardiac activity. This mimicing occurs as a consequence of detection by defribrillator protection structures or by amplifier saturation from RF artifacts insufficiently suppressed by input QRS bandpass filters. The new functions under development employ a separate EMI detection receiver for controlling the pacemaker mode to minimize inhibition by PEMI.