Uncertainty Analysis of a Multifunctional Tribometer

In response to the high cost and limited instrumentation available on commercial tribometers a student designed tribometer was conceived, built, and tested. This tribometer combines multiple tribology testing configurations into a single compact and reconfiguration tribometer, dubbed the multifunctional tribometer. This tribometer is also capable of operating in expanded experimental spaces not covered within the limited scope of industry standardized tribological tests. Specifically, this tribometer is able to conduct rotary tests in a reciprocating fashion; this capability is unavailable on any other tribometer published so far in literature or available commercially. Following an overview of the industry standards and the tribometer’s capability is an uncertainty analysis for the reciprocating block on ring testing regime of the multifunctional tribometer. As this test method is totally unique to this machine it is necessary to prove its validity and accuracy. This is done through the use of an uncertainty analysis which is then expanded across all experimental spaces covered by the testing configuration. Additionally, an uncertainty budget has been made which shows what aspects of the machine would be most worthwhile to upgrade to improve performance. Finally, a case study is included which involves an experiment testing the lubrication properties of WD40 in this reciprocating block on ring configuration of the multifunctional tribometer

Is Elective Vulvar Plastic Surgery Ever Warranted, and What Screening Should Be Conducted Preoperatively?

Introduction.  Elective vulvar plastic surgery was the topic of a heated discussion on the list-serve of the International Society for the Study of Women's Sexual Medicine. At the suggestion of a board member, it was determined that this discussion might of interest to journal readers in the form of a published controversy. Methods.  Six people with expertise and/or strong opinions in the area of vulvar health, several of whom had been involved in the earlier online discussion, were invited to submit evidence-based opinions on the topic. Main Outcome Measure.  To provide food for thought, discussion, and possible further research in a poorly discussed area of sexual medicine. Results.  Goodman believes that patients should make their own decisions. Bachmann further states that, while that is a woman's right, she should be counseled first, because variations in looks of the vulvar region are normal. Johnson furthers this thought, discussing the requirement for counseling before performing reinfibulation surgery on victims of female genital cutting. Fourcroy emphasizes the need to base surgical procedures on safety and efficacy in the long term, and not merely opportunity at the moment. Goldstein and Goldstein state that, based on the four principles of ethical practice of medicine, vulvar plastic surgery is not always ethical, but not always unethical. Sklar pursues this thought further, pointing out specific examples in regard to the principles of ethics. Conclusion.  Vulvar plastic surgery may be warranted only after counseling if it is still the patient's preference, provided that it is conducted in a safe manner and not solely for the purpose of performing surgery. Goodman MP, Bachmann G, Johnson C, Fourcroy JL, Goldstein A, Goldstein G, and Sklar S. Is elective vulvar plastic surgery ever warranted, and what screening should be done preoperatively? J Sex Med 2007;4:269–276.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72245/1/j.1743-6109.2007.00431.x.pd

Fatigue states after cancer treatment occur both in association with, and independent of, mood disorder: a longitudinal study

BACKGROUND: Persistent fatigue is recognised as one of the most common, ongoing symptoms reported by patients following cancer treatment and may have profound effects on the quality of life. However, recent cross-sectional studies also highlight the close relationship between cancer related fatigue (CRF) and diagnoses of depression or anxiety disorder. There is currently limited information about the relationships between these conditions over time. We sought to examine the longitudinal relationships between fatigue and mood disorder in women treated with adjuvant therapy for early stage breast cancer. METHODS: Women who had recently completed adjuvant therapy for Stage I or II breast cancer (n = 212) were sent a questionnaire with established case thresholds for clinically-significant fatigue and psychological disorder, as well as a questionnaire assessing disability. Potentially relevant variables linked to fatigue states, including age, treatment modality, menopausal status, and hematological indices were recorded. The illness outcomes were assessed over 48 months of follow-up. RESULTS: The 176 women who responded to the questionnaire (84%) had a mean age of 55 (range 24–83) years and had completed adjuvant treatment on average 10 (range 4.7 – 16.3) months previously. Radiotherapy had been administered, either alone (50% of women) or in combination with chemotherapy (36%). Responses from 87 women (48%) indicated a significant fatigue state (termed here post-cancer fatigue; PCF), and from 59 women (33%) responses indicated significant psychological distress. Thirty-four women (19%) were cases of fatigue alone (i.e. unaccompanied by psychological disorder), whereas 52 (30%) were cases of both disorders. Multivariate analysis did not reveal any association between demographic, clinical or laboratory variables, and caseness for PCF. Self-reported functional disability was significantly associated with fatigue. Follow-up at 24, 36 and 48 months revealed high rates of ongoing PCF in conjunction with psychological distress, despite falling rates of psychological distress alone and fatigue alone. CONCLUSION: Post-cancer fatigue was prevalent and sustained on follow-up. Concurrent psychological disorder was evident in the majority, but not all, cases of PCF and tended to be sustained over time. Further prospective cohort studies to define the longitudinal co-morbid relationships between fatigue, mood disorder, and ongoing disability after cancer treatment are indicated

A genome-wide linkage scan for body mass index on Framingham Heart Study families

BACKGROUND: Genome-wide scan data from a community-based sample was used to identify the genetic factors that affect body mass index (BMI). BMI was defined as weight (kg) over the square of height (m), where weight and height were obtained from the first measurement available between the ages of 40 and 50 years. RESULTS: Significant familial correlations were observed in mother:father (spouse) relative pairs and in all relative pairs examined except parent:daughter pairs. Single-point sib-pair regression analysis provided nominal evidence for linkage (p < 0.05) of loci to BMI at 23 markers. Multi-point sib-pair regression analysis provided nominal evidence for linkage to BMI at 42 loci on 12 chromosomes. Empirical p-values showed results consistent with the multi-point results; all but three of the loci identified by multi-point analysis were also significant. CONCLUSION: The largest regions of nominally significant linkage were found on chromosomes 2, 3, and 11. The most significant evidence for linkage was obtained with markers D2S1788, D2S1356, D2S1352, D3S1744, and D11S912 from multi-point sib-pair single-trait regression analysis. Our results are in agreement with some of the recently published reports on BMI using various data sets including the Framingham Heart Study data

Thermal receptivity of free convective flow from a heated vertical surface: linear waves

Numerical techniques are used to study the receptivity to small-amplitude thermal disturbances of the boundary layer flow of air which is induced by a heated vertical flat plate. The fully elliptic nonlinear, time-dependent Navier–Stokes and energy equations are first solved to determine the steady state boundary-layer flow, while a linearised version of the same code is used to determine the stability characteristics. In particular we investigate (i) the ultimate fate of a localised thermal disturbance placed in the region near the leading edge and (ii) the effect of small-scale surface temperature oscillations as means of understanding the stability characteristics of the boundary layer. We show that there is a favoured frequency of excitation for the time-periodic disturbance which maximises the local response in terms of the local rate of heat transfer. However the magnitude of the favoured frequency depends on precisely how far from the leading edge the local response is measured. We also find that the instability is advective in nature and that the response of the boundary layer consists of a starting transient which eventually leaves the computational domain, leaving behind the large-time time-periodic asymptotic state. Our detailed numerical results are compared with those obtained using parallel flow theory

Emulation and History Matching using the hmer Package

Modelling complex real-world situations such as infectious diseases, geological phenomena, and biological processes can present a dilemma: the computer model (referred to as a simulator) needs to be complex enough to capture the dynamics of the system, but each increase in complexity increases the evaluation time of such a simulation, making it difficult to obtain an informative description of parameter choices that would be consistent with observed reality. While methods for identifying acceptable matches to real-world observations exist, for example optimisation or Markov chain Monte Carlo methods, they may result in non-robust inferences or may be infeasible for computationally intensive simulators. The techniques of emulation and history matching can make such determinations feasible, efficiently identifying regions of parameter space that produce acceptable matches to data while also providing valuable information about the simulator's structure, but the mathematical considerations required to perform emulation can present a barrier for makers and users of such simulators compared to other methods. The hmer package provides an accessible framework for using history matching and emulation on simulator data, leveraging the computational efficiency of the approach while enabling users to easily match to, visualise, and robustly predict from their complex simulators.Comment: 40 pages, 11 figures; submitted to Journal of Statistical Software: author order correcte

Genomic regions linked to alcohol consumption in the Framingham Heart Study

BACKGROUND: Pedigree, demographic, square-root transformed maximum alcohol (SRMAXAPD) and maximum cigarette (MAXCPD) consumption, and genome-wide scan data from the Framingham Heart Study (FHS) were used to investigate genetic factors that may affect alcohol and cigarette consumption in this population-based sample. RESULTS: A significant sister:sister correlation greater than spouse correlation was observed for MAXCPD only. Single-point sib-pair regression analysis provided nominal evidence for linkage of loci to both SRMAXAPD and MAXCPD consumption traits, with more significant evidence of linkage to SRMAXAPD than to MAXCPD. One genomic region, chr9q21.11, exhibits significant multi-point sib-pair regression to SRMAXAPD. CONCLUSION: SRMAXAPD exhibits greater evidence for genetic linkage than does MAXCPD in the FHS sample. Four regions of the genome exhibiting nominal evidence for linkage to SRMAXAPD in the FHS sample correspond to regions of the genome previously identified as linked to alcoholism or related traits in the family data set ascertained on individuals affected with alcohol dependence known as COGA

The SAMI Galaxy Survey: energy sources of the turbulent velocity dispersion in spatially-resolved local star-forming galaxies

We investigate the energy sources of random turbulent motions of ionised gas from H$\alpha$ emission in eight local star-forming galaxies from the Sydney-AAO Multi-object Integral field spectrograph (SAMI) Galaxy Survey. These galaxies satisfy strict pure star-forming selection criteria to avoid contamination from active galactic nuclei (AGN) or strong shocks/outflows. Using the relatively high spatial and spectral resolution of SAMI, we find that -- on sub-kpc scales our galaxies display a flat distribution of ionised gas velocity dispersion as a function of star formation rate (SFR) surface density. A major fraction of our SAMI galaxies shows higher velocity dispersion than predictions by feedback-driven models, especially at the low SFR surface density end. Our results suggest that additional sources beyond star formation feedback contribute to driving random motions of the interstellar medium (ISM) in star-forming galaxies. We speculate that gravity, galactic shear, and/or magnetorotational instability (MRI) may be additional driving sources of turbulence in these galaxies.Comment: 11 pages, 5 figures, 3 tables. Accepted by MNRA