Caries inhibition with a CO2 9.3 μm laser: An in vitro study.

Background And Objectives: The caries preventive effects of different laser wavelengths have been studied in the laboratory as well as in pilot clinical trials. The objective of this in vitro study was to evaluate whether irradiation with a new 9.3 μm microsecond short-pulsed CO2 -laser could enhance enamel caries resistance with and without additional fluoride applications.

Professional practice skills for nurses.

Nurses work in a healthcare system in which different partners in care have different expectations of them. Demands to provide compassionate care that is patient-centred and responsive while adhering to budget constraints are contributing to 'compassion fatigue' and adversely affecting nurses' mood and effectiveness. This article discusses how an understanding of professional practice skills, communication skills and teamwork can help nurses to cope with these conflicting demands and compassion fatigue while performing their professional roles and responsibilities.

Effects of covered solid sorbent tube sample holders on organic vapor measurements.

A study was conducted to examine whether there are significant differences between organic vapor concentrations measured using charcoal tubes with three different configurations: uncovered sample holder (open tube), SKC, and Buck brand covered sample holders. A fractional factorial experimental design was used with the following factors and levels: vapor (n-hexane vs. m-xylene), pump type (pulsating vs.

Comparison of artificial neural network (ANN) and partial least squares (PLS) regression models for predicting respiratory ventilation: an exploratory study.

The objective of this study was to assess the potential for using artificial neural networks (ANN) to predict inspired minute ventilation (V(I)) during exercise activities. Six physiological/kinematic measurements obtained from a portable ambulatory monitoring system, along with individual's anthropometric and demographic characteristics, were employed as input variables to develop and optimize the ANN configuration with respect to reference values simultaneously measured using a pneumotachograph (PT). The generalization ability of the resulting two-hidden-layer ANN model was compared with a linear predictive model developed through partial least squares (PLS) regression, as well as other V(I) predictive models proposed in the literature.

Laboratory evaluation of a physiologic sampling pump (PSP).

Recently, physiologic sampling pumps (PSPs), which can adjust their sampling rates in proportion to wearers' minute ventilation (V[combining dot above](E)), have been proposed to better estimate exposure to airborne contaminants in the workplace. A laboratory evaluation was conducted to compare the performance of a new PSP with a traditional sampling pump (TSP) in an exposure chamber. Fifteen subjects (aged 19-36 years) performed two replicate sessions of step-tests for correlated and uncorrelated exposure scenarios on four separate days.

A novel physiologic sampling pump capable of rapid response to breathing.

The merits of using physiologic sampling pumps (PSPs) instead of using constant-flow sampling pumps, i.e., "traditional sampling pumps" (TSPs), are discussed.

Exposure assessment by physiologic sampling pump--prediction of minute ventilation using a portable respiratory inductive plethysmograph system.

A study was conducted to evaluate a portable respiratory inductive plethysmograph (RIP) as a means to estimate minute ventilation (V(E)) for use in controlling the flow rate of a physiologic sampling pump (PSP). Specific aims were to: (1) evaluate the ability of the portable RIP system to measure V(E) using a direct (individual) fixed-volume calibration method (Direct RIP model), (2) develop and evaluate the performance of indirect (group) regression models for V(E) prediction using output data from the portable RIP and subject demographic characteristics (Indirect RIP model), and (3) compare V(E) estimates from indirect and direct portable RIP calibration with indirect estimation models published previously. Nine subjects (19-44 years) were divided into calibration (n = 6) and test (n = 3) datasets and performed step-tests on three different days while wearing the portable RIP and breathing through a pneumotachometer (reference).

Risk assessment for loader- and dozer-related fatal incidents in U.S. mining.

The paper presents the results of research aimed at developing a risk assessment process that can be used to more thoroughly characterise risks associated with loader- and dozer-related fatal incidents in US mining. The assessment is based on historical data obtained from the US Mine Safety and Health Administration investigation reports, which includes 77 fatal incidents that occurred from 1995 to 2006. The Preliminary Hazard Assessment method is used in identifying and quantifying risks.

Analysis of fatalities and injuries involving mining equipment.

Introduction: Despite significant reductions, the number of injuries and fatalities in mining remains high. A persistent area of concern continues to be equipment-related incidents.

Method: Mine Safety and Health Administration (MSHA) and Current Population Survey (CPS) data were used to examine equipment-related injuries over the period 1995-2004.

Surface acoustic wave (SAW) microsensor array for measuring VOCs in drinking water.

Exposure to volatile organic chemicals (VOCs) in drinking water has been linked to a number of adverse health effects including cancer, liver, and kidney damage. However, the large number of potential contaminants and the cost and complexity of existing analytical methods limits the extent to which water quality is routinely characterized. This project focused on the laboratory development and evaluation of an instrument for field analysis of VOCs in drinking water.

Laboratory and field evaluation of a SAW microsensor array for measuring perchloroethylene in breath.

This article describes the laboratory and field performance evaluation of a small prototype instrument employing an array of six polymer-coated surface acoustic wave (SAW) sensors and a thermal desorption preconcentration unit for rapid analysis of perchloroethylene in breath. Laboratory calibrations were performed using breath samples spiked with perchloroethylene to prepare calibration standards spanning a concentration range of 0.1-10 ppm.

Evaluation of a fluorometric method for measuring low concentrations of ammonia in ambient air.

A fluorometric method developed for measuring low concentrations of ammonium in marine and freshwater ecosystems was adapted for the analysis of ammonia in ambient air. The modified method entails collection of samples on an acid-treated solid adsorbent followed by analysis using a fluorometer. Optimal results were obtained using a commercially available sorbent tube containing 100 mg of acid-treated silica gel for sample collection, and an analytical protocol consisting of sample desorption in DI water, addition of orthopthaldialdehyde (OPA) working reagent, and room temperature incubation.

Prototype sampling system for measuring workplace protection factors for gases and vapors.

A prototype sampling system for measuring respirator workplace protection factors (WPFs) was developed. Methods for measuring the concentration of contaminants inside respirators have previously been described; however, these studies have typically involved continuous sampling of aerosols. Our work focuses on developing an intermittent sampling system designed to measure the concentration of gases and vapors during inspiration.

Analysis of solvent vapors in breath and ambient air with a surface acoustic wave sensor array.

This article describes the development and evaluation of a small prototype instrument employing an array of four polymer-coated surface acoustic wave (SAW) sensors for rapid analysis of organic solvent vapors in exhaled breath and ambient air. A thermally desorbed adsorbent preconcentrator within the instrument is used to increase sensitivity and compensate for background water vapor. Calibrations were performed for breath and dry nitrogen samples in Tedlar bags spiked with 16 individual solvents and selected binary mixtures.

Vascular dementia and Alzheimer's disease: is there a difference? A comparison of symptoms by disease duration.

This study examined differences between vascular dementia (VaD) by the NINDS/AIRENS criteria and Alzheimer's disease (AD) on clinical grounds. A consecutive series of 517 patients with probable and possible VaD or AD were evaluated for cognitive, functional, and behavioral symptoms and separated into three subgroups by duration of dementia. These AD and VaD subgroups were then compared on a series of standardized clinical measures.

Effectiveness of roll-over protective structures in reducing farm tractor fatalities.

Objective: The purpose of this systematic review was to evaluate the effectiveness of roll-over protection structures (ROPS) as an engineering control for prevention of fatalities from farm tractor roll-overs.

Methods: Using a systematic approach to literature searching, relevant studies from peer-reviewed journals, technical and government reports, and unpublished reports were retrieved. Studies meeting initial criteria for possible inclusion were screened to determine whether they addressed the review topic (ROPS), included comparison data and included outcomes data such as injury or fatality.

Vapor recognition with small arrays of polymer-coated microsensors. A comprehensive analysis.

A comprehensive analysis of vapor recognition as a function of the number of sensors in a vapor-sensor array is presented. Responses to 16 organic vapors collected from six polymer-coated surface acoustic wave (SAW) sensors were used in Monte Carlo simulations coupled with pattern recognition analyses to derive statistical estimates of vapor recognition rates as a function of the number of sensors in the array (< or = 6), the polymer sensor coatings employed, and the number and concentration of vapors being analyzed. Results indicate that as few as two sensors can recognize individual vapors from a set of 16 possibilities with < 6% average recognition error, as long as the vapor concentrations are > 5 x LOD for the array.

Establishing a limit of recognition for a vapor sensor array.

Organic vapor analysis with microsensor arrays relies principally on two output parameters: the response pattern, which provides qualitative information, and the response sensitivity, which determines the limit of detection (LOD). The latter is used to define the operating limit in the low-concentration range, under the implicit assumption that, if a vapor can be detected, it can be identified and differentiated from other vapors on the basis of its response pattern. In this study, the performance of an array of four polymer-coated surface acoustic wave vapor sensors was explored using calibrated response data from 16 solvent vapors in Monte Carlo simulations coupled with pattern recognition analysis.

Prototype instrument employing a microsensor array for the analysis of organic vapors in exhaled breath.

A prototype portable instrument capable of selectively measuring organic vapors in breath at low- and sub-ppm concentrations was tested. The instrument employs an array of four polymer-coated surface-acoustic-wave (SAW) resonators and microprocessor-controlled pumps, valves, and heating elements for preconcentration and thermal desorption of breath samples. Response data are passed to an external personal computer for processing.

Investigation of organic vapor losses to condensed water vapor in Tedlar bags used for exhaled-breath sampling.

This study evaluated the potential loss of organic vapors to condensed water in bags used for breath sampling. "Wet" test atmospheres were prepared by transferring nitrogen into 1-L Tedlar bags and spiking with water and each of several organic solvents (methanol, acetone, 2-butanone,m-xylene, 1,1,1 trichloroethane, and perchloroethylene) to yield atmospheres representative of a 500-mL breath sample collected at 37 degrees C and cooled to 25 degrees C. Vapor concentrations were compared with those in bags prepared without water.

A computerized system for rapid retrieval and compilation of critical or interesting patient data.

The timely availability and presentation of critical and interesting patient data is essential to ensure quality patient care as well as ease of recognition and, secondarily, to provide material for teaching and research. The ability to accomplish these goals expeditiously in a complex and busy clinical laboratory may be difficult to acquire. An on-line, computerized system has been developed which automatically searches each patient record for up to 600 different laboratory tests, compares each result against individually established limits, and then formats pertinent test results for maximum discrimination.

Computerized system for a nutritional support service.

The development of a computerized system for the assistance of a nutritional support service (NSS) is described. A cooperative program exists between the NSS and the Department of Laboratory Medicine, whose computer system is used to support the activities of the NSS. A record is maintained on each patient followed by the NSS (15-20 patients per day).

A computerized system for the identification of alloimmune neutropenia in neonates.

In an attempt to determine the incidence of alloimmune neonatal neutropenia, a systematic study was initiated during a period of six months. Complete blood count, differential and absolute neutrophil count of all the newborns were determined to identify the newborns with neutropenia and those with persistent neutropenia were evaluated for the presence of maternal neutrophil antibodies. This resulted in the design and use of a computerized system which was successfully employed to identify several neonates born with this disorder.