The 2016 Revision of ISO 1 - Standard Reference Temperature for the Specification of Geometrical and Dimensional Properties.

This paper discusses the changes in the 2016 (third edition) of International Standard ISO 1. While the value of the standard reference temperature remains unchanged at 20 °C, the important definitions for the "reference temperature" and "standard reference temperature," absent in prior editions, are now defined, with the latter exclusively reserved for the assignment of the internationally agreed upon temperature of 20 °C. The scope of the revised Standard has been carefully refined and made more explicit. This, together with other clarifications and improvements, has eliminated the ambiguities associated with specifications at non-standard reference temperatures and allows, if needed, different reference temperatures to be associated with different properties of a workpiece. The relationship between ISO 1 and dimensional measurements is also discussed and clarified. In this paper, we discuss the motivation for these changes and present several issues debated during the revision process for the benefit of future standards committees that might study this topic.

Microbubbles are detected prior to larger bubbles following decompression.

Using dual-frequency ultrasound (DFU), microbubbles (<10 µm diameter) have been detected in tissue following decompression. It is not known if these microbubbles are the precursors for B-mode ultrasound-detectable venous gas emboli (bmdVGE). The purpose of this study was to determine if microbubbles could be detected intravascularly postdecompression and to investigate the temporal relationship between microbubbles and larger bmdVGE. Anesthetized swine (n = 15) were exposed to 4.0-4.5 ATA for 2 h, followed by decompression to 0.98 ATA. Microbubble presence and VGE grade were measured using DFU and B-mode ultrasound, respectively, before and for 1 h postdecompression, approximately every 4-5 min. Microbubbles appeared in the bloodstream postdecompression, both in the presence and absence of bmdVGE. In swine without bmdVGE, microbubbles remained elevated for the entire 60-min postdecompression period. In swine with bmdVGE, microbubble signals were detected initially but then returned to baseline. Microbubbles were not detected with the sham dive. Mean bmdVGE grade increased over the length of the postdecompression data collection period. Comparison of the two response curves revealed significant differences at 5 and 10 min postdecompression, indicating that microbubbles preceded bmdVGE. These findings indicate that decompression-induced microbubbles can 1) be detected intravascularly at multiple sites, 2) appear in the presence and absence of bmdVGE, and 3) occur before bmdVGE. This supports the hypothesis that microbubbles precede larger VGE bubbles. Microbubble presence may be an early marker of decompression stress. Since DFU is a low-power ultrasonic method, it may be useful for operational diving applications.

Microbubble detection following hyperbaric chamber dives using dual-frequency ultrasound.

Venous gas emboli (VGE) can be readily detected in the bloodstream using existing ultrasound methods. No method currently exists to detect decompression-induced microbubbles in tissue. We hypothesized that dual-frequency ultrasound (DFU) could detect these microbubbles. With DFU, microbubbles are driven with two frequencies: a lower "pump" (set to the resonant frequency of the desired bubble size) and a higher "image" frequency. A bubble of the resonant size emits the sum and difference of the two transmitted frequencies. For this study we used a pump frequency of 2.25 MHz and an image frequency of 5.0 MHz, which detects bubbles of roughly 1-10 µm in diameter in a water tank. Four anesthetized swine were pressurized at 4.5 ATA for 2 h and decompressed over 5 min, inducing moderate to very severe VGE scores. Four sites on the thigh of each swine were monitored with DFU before and after the dives. A single mock dive was also performed. The number of sites returning signals consistent with microbubbles increased dramatically after the chamber dive (P < 0.01), but did not change with the mock dive. The increase in DFU signal after the chamber dive was sustained and present at multiple sites in multiple swine. This research shows for the first time that decompression-induced tissue microbubbles can be detected using DFU and that DFU could be used to monitor decompression-induced microbubbles at multiple sites on the body. Additionally, DFU could be used to track the time course of microbubble formation and growth during decompression stress.

Signals consistent with microbubbles detected in legs of normal human subjects after exercise.

Exercise may produce micronuclei (presumably gas-filled bubbles) in tissue, which could serve as nucleation sites for bubbles during subsequent decompression stress. These micronuclei have never been directly detected in humans. Dual-frequency ultrasound (DFU) is a resonance-based, ultrasound technique capable of detecting and sizing small stationary bubbles. We surveyed for bubbles in the legs of six normal human subjects (ages 28-52 yr) after exercise using DFU. Eleven marked sites on the left thigh and calf were imaged using standard imaging ultrasound. Subjects then rested in a reclining chair for 2 h before exercise. For the hour before exercise, a series of baseline measurements was taken at each site using DFU. At least six baseline measurements were taken at each site. Subjects exercised at 80% of their age-adjusted maximal heart rate for 30 min on an upright bicycle ergometer. After exercise, the subjects returned to the chair, and multiple postexercise measurements were taken at the marked sites. Measurements continued until no further signals consistent with bubbles were returned or 1 h had elapsed. All subjects showed signals consistent with bubbles after exercise at at least one site. The percentage of sites in a given subject showing signals significantly greater than baseline (P < 0.01) at first measurement ranged from 9.1 to 100%. Overall, 58% of sites showed signals consistent with bubbles at the first postexercise measurement. Signals decreased over time after exercise. These data strongly suggest that exercise produces bubbles detectable using DFU.

Dual-frequency ultrasound detection of stationary microbubbles in tissue.

Indirect evidence suggests that microbubbles that exist normally in tissue may play a key role in decompression sickness (DCS). Their sizes and locations are unknown. Dual-frequency ultrasound (DFU) exploits bubble resonance to detect bubbles over a wide size range and could potentially detect stationary tissue microbubbles. To test this capability, DFU was used to detect stationary microbubbles of known size (2-3 microm mean diameter) over a range of ultrasound pressures and microbubble concentrations. In gelatin phantoms doped with microbubbles and in ex vivo porcine tissue, signals indicative of bubbles were detected for microbubble concentrations of 5x10(5) per mL and greater. Signals were not returned from solid particle microspheres of similar size to the microbubbles or from saline controls. In the thigh of an anesthetized swine, signals were detected for concentrations of 5x10(7) per mL and greater. Because of its ability to detect bubbles over a wide range of sizes, this technique could potentially detect naturally-existing microbubbles in tissue and lead to (a) an improved understanding of the mechanics of bubble formation during decompression and (b) a new metric for evaluating DCS.

Uncertainty Due to Finite Resolution Measurements.

We investigate the influence of finite resolution on measurement uncertainty from the perspective of the Guide to the Expression of Uncertainty in Measurement (GUM). Finite resolution in a measurement that is perturbed by Gaussian noise yields a distribution of results that strongly depends on the location of the true value relative to the resolution increment. We show that there is no simple expression relating the standard deviation of the distribution of measurement results to the associated uncertainty at a specified level of confidence. There is, however, an analytic relation between the mean value and the standard deviation of the measurement distribution. We further investigate the conflict between the GUM and ISO 14253-2 regarding the method of evaluating the standard uncertainty due to finite resolution and show that, on average, the GUM method is superior, but still approximate.

Acupuncture for the alleviation of lateral epicondyle pain: a systematic review.

OBJECTIVES: Lateral epicondyle pain is a common complaint in North America. In the past 10 yr acupuncture has become increasingly recognized as an alternative treatment for pain, including epicondyle pain. This review evaluates the effectiveness of acupuncture as a treatment for lateral epicondylitis using the appropriate analysis. METHODS: Online bibliographic database searches in any language from Medline, PsychINFO, CINAHL, Healthstar, PMID, CAM, EMBASE, Cochrane Database of Systematic Review (3rd quarter 2003), articles listed in reference lists of key articles and the author's personal files were performed. Randomized and quasi-randomized controlled trials examining the effects of acupuncture on lateral epicondyle pain were selected. From the six studies that met inclusion criteria, the first author, year of publication, population studied, dropout rate, treatment plan, assessment scale and outcome measures were extracted. Study quality was determined by using the Jadad scale, in which all studies were rated as high quality. A best evidence synthesis approach was used to analyse the data presented in the six studies. RESULTS: All the studies suggested that acupuncture was effective in the short-term relief of lateral epicondyle pain. Five of six studies indicated that acupuncture treatment was more effective compared to a control treatment. CONCLUSIONS: There is strong evidence suggesting that acupuncture is effective in the short-term relief of lateral epicondyle pain.

Low back pain at presentation in a newly diagnosed diabetic.

Insulin dependent diabetes mellitus predisposes to a range of different and unusual infections, including epidural and psoas abscesses. However, they occur mainly in adults with longstanding diabetes. We report the case of a 12 year old boy who presented with diabetic ketoacidosis and low back pain, and was subsequently diagnosed with both a left psoas abscess and an extensive thoracolumbar spinal epidural abscess measuring 20 cm in length. This case report highlights the need to maintain a high index of suspicion for epidural abscesses in children presenting with fever and localised back pain. Early diagnosis with appropriate imaging and aggressive management can prevent development of permanent neurological damage as was the case in our patient.

Moving assertive community treatment into standard practice.

This article describes the assertive community treatment model of comprehensive community-based psychiatric care for persons with severe mental illness and discusses issues pertaining to implementation of the model. The assertive community treatment model has been the subject of more than 25 randomized controlled trials. Research has shown that this type of program is effective in reducing hospitalization, is no more expensive than traditional care, and is more satisfactory to consumers and their families than standard care. Despite evidence of the efficacy of assertive community treatment, it is not uniformly available to the individuals who might benefit from it.

Measuring outcomes of care for adolescents with emotional and behavioral problems.

OBJECTIVES: To validate the prototype Adolescent Treatment Outcomes Module (ATOM), examine its sensitivity to clinical change, and determine its feasibility for administration in routine clinical settings. METHOD: A sample of 67 adolescents, aged 11 through 18, was selected from new patients at two inpatient and two outpatient mental health programs. Adolescents and parents completed the ATOM and validating instruments at intake, 1 week postintake, and again at 6 months. RESULTS: Nine self-report symptoms predicted positive diagnoses of oppositional defiant, conduct, anxiety, and depressive disorders on the basis of structured diagnoses, with sensitivities of 0.7 to 0.8. Test-retest correlations for outcome scales were largely excellent (>0.70). Scales that measured functioning at home, in school, and in the community were moderately correlated in the expected direction with global functioning. Decreases in symptom severity and functional impairment were generally associated with decreases in validating instruments. Administration time averaged 25 minutes for adolescents and 28 minutes for parents. CONCLUSIONS: Both parents and adolescents readily completed the ATOM. Module scales demonstrated excellent reliability and good to fair concurrent validity. The ATOM was able to detect change and its absence.

A Careful Consideration of the Calibration Concept.

This paper presents a detailed discussion of the technical aspects of the calibration process with emphasis on the definition of the measurand, the conditions under which the calibration results are valid, and the subsequent use of the calibration results in measurement uncertainty statements. The concepts of measurement uncertainty, error, systematic error, and reproducibility are also addressed as they pertain to the calibration process.

Toward a level playing field: predictive factors for the outcomes of mental health treatment for adolescents.

OBJECTIVE: To understand better the effectiveness of routine treatment for emotional and behavioral problems experienced by adolescents, methods are needed to control for between-provider differences in the distribution of factors that adversely affect treatment success. Such methods are necessary to fairly compare providers' outcomes and to aid clinicians in identifying adolescents for whom routine care may need to be altered. As a preliminary step toward developing a model to adjust treatment outcomes to account for predictive factors, findings from studies of treated samples of adolescents were reviewed to identify the factors that influence the likelihood of treatment success for this population. METHOD: Medline and PSYCInfo databases were searched for studies of treated adolescents that reported the association between expert-nominated predictive factors and outcomes. Thirty-four studies met inclusion criteria. RESULTS: Significant predictors identified in these studies include diagnosis, baseline severity of symptoms and functional impairment, family dysfunction, and previous treatment. Several expert-nominated factors have not been adequately studied in treated samples. CONCLUSIONS: Much basic work is needed before a convincing body of empirical evidence can explain predictive factors for adolescent mental health treatment outcomes. Future efforts should determine a reduced set of predictive factors that can be measured with minimal burden to providers.

Theoretical analysis of a dripping faucet.

While previous studies of continuous emission of drops from a faucet have shown the richness of the system's nonlinear response, a theory of dripping has heretofore been lacking. Long-time behavior of dripping is simulated computationally by tracking the formation of up to several hundred drops in a sequence, rather than the usual single drop, at a given flow rate Q and verified by experiments. As Q increases, the system evolves from a period-1 system through a number of period doubling (halving) bifurcations as dripping ultimately gives way to jetting. That hysteresis can occur is also demonstrated.

An investigation into the risk of air embolus during veno-venous bypass in orthotopic liver transplantation.

After observing micro-bubble activity in the venovenous bypass system during liver transplantation, an experiment was designed to investigate the origin of these bubbles and to define the conditions under which they occurred. Using a Biomedicus constrained vortex pump and a customized circuit design, microbubble activity was measured in saline and blood media during varying pre- and post-head pressures. The data show that air emboli can be generated from this pump and the rate at which they develop is directly related to the pre- and post-head pressure and hematocrit.

Calculation of Measurement Uncertainty Using Prior Information.

We describe the use of Bayesian inference to include prior information about the value of the measurand in the calculation of measurement uncertainty. Typical examples show this can, in effect, reduce the expanded uncertainty by up to 85 %. The application of the Bayesian approach to proving workpiece conformance to specification (as given by international standard ISO 14253-1) is presented and a procedure for increasing the conformance zone by modifying the expanded uncertainty guard bands is discussed.

Women and career development: a decade of research.

This chapter reviews the vocational experiences of women as they have been revealed in the literature during the past decade. The review considers primarily empirical literature; findings are sampled relative to women's self-concept development, readiness for vocational choices, actual choices made, work-force entry, experiences at work, and retirement. Suggestions are made regarding the next generation of research on women and career development.