Image-Current Mediated Sympathetic Laser Cooling of a Single Proton in a Penning Trap Down to 170 mK Axial Temperature.

We demonstrate a new temperature record for image-current mediated sympathetic cooling of a single proton in a cryogenic Penning trap by laser-cooled ^{9}Be^{+}. An axial mode temperature of 170 mK is reached, which is a 15-fold improvement compared to the previous best value. Our cooling technique is applicable to any charged particle, so that the measurements presented here constitute a milestone toward the next generation of high-precision Penning-trap measurements with exotic particles.

Massive clonal expansion of medulloblastoma-specific T cells during adoptive cellular therapy.

In both human and murine systems, we have developed an adoptive cellular therapy platform against medulloblastoma and glioblastoma that uses dendritic cells pulsed with a tumor RNA transcriptome to expand polyclonal tumor-reactive T cells against a plurality of antigens within heterogeneous brain tumors. We demonstrate that peripheral TCR Vß repertoire analysis after adoptive cellular therapy reveals that effective response to adoptive cellular therapy is concordant with massive in vivo expansion and persistence of tumor-specific T cell clones within the peripheral blood. In preclinical models of medulloblastoma and glioblastoma, and in a patient with relapsed medulloblastoma receiving adoptive cellular therapy, an early and massive expansion of tumor-reactive lymphocytes, coupled with prolonged persistence in the peripheral blood, is observed during effective therapeutic response to immunotherapy treatment.

Future hospital service utilisation in older adults living in long-term residential aged care or the community hospitalised with a fall-related injury.

This study identified group-based trajectories of hospitalisation for older adults who were living in residential aged care facilities (RACF) or the community for up to 4 years after an index fall injury hospitalisation. Greater than 3 subsequent fall injury hospitalisations and time until move to a RACF were key predictors of RACF and community-living trajectory group memberships, respectively. INTRODUCTION: To examine hospital service use trajectories of people aged ≥ 65 years who had a fall injury hospitalisation and were either living in a residential aged care facility (RACF) or the community at the time of the index fall and to identify factors predictive of their trajectory group membership. METHOD: A group-based trajectory analysis of hospitalisations of people aged ≥ 65 years who had a fall injury hospitalisation during 2008-2009 in New South Wales, Australia, was conducted. Linked hospitalisation and RACF data were examined for a 5-year period. Group-based trajectory models were derived based on number of subsequent hospital admissions following the index fall injury hospitalisation. Multinominal logistic regression examined predictors of trajectory group membership. RESULTS: There were 24,729 fall injury hospitalisations; 78.8% of fallers were living in the community and 21.2% in a RACF. Five distinct trajectory groups were identified for community-living and four trajectory groups for RACF residents. Key predictors of trajectory group membership for both community-living and RACF residents were age group, number of comorbidities and dementia status. For RACF residents, depression, assistance with activities of daily living and number of subsequent fall injury admissions were also predictors of group membership, with time to move to a RACF a predictor of group membership for community living. CONCLUSIONS: Identifying trajectories of ongoing hospital use informs targeting of strategies to reduce hospital admissions and design of services to allow community-living individuals to remain as long as possible within their own residence.

Impact of cellular microenvironment and mechanical perturbation on calcium signalling in meniscus fibrochondrocytes.

Mechanical signals regulate a multitude of cell functions and ultimately govern fibrous tissue growth, maintenance and repair. Such mechanotransduction processes often involve modulation of intracellular calcium concentration ([Ca2+]i). However, most studies interrogate these responses in cells in simplified culture systems, thereby removing potentially important inputs from the native extracellular microenvironment. The objective of this study was to test the hypothesis that the intracellular calcium response of meniscus fibrochondrocytes (MFCs) is dependent on both the microenvironmental context in which this perturbation is applied and on the tensile deformation. Using a custom micro-mechanical tester mounted on a confocal microscope, intracellular calcium activity in MFCs in response to incremental tissue strains (0, 3, 6 and 9 %) was monitored in situ (i.e., in the native tissues) on MFC-seeded aligned scaffolds and MFC-seeded silicone membranes. The [Ca2+]i regulation by MFCs within the native meniscus tissue microenvironment was considerably different from [Ca2+]i regulation by MFCs on either aligned nanofibrous scaffolds or flat silicone membranes. Additionally, increasing levels of tensile deformation resulted in a greater number of responding cells, both in situ and in vitro, while having no effects on temporal characteristics of [Ca2+]i signalling. Collectively, these findings have significant implications for mechanobiology of load-bearing fibrous tissues and their responses to injury and degeneration. In addition, from a tissue engineering perspective, the findings establish cellular benchmarks for maturing engineered constructs, where native tissue-like calcium mechano-regulation may be an important outcome parameter to achieve mechanical functionality comparable to native tissue.

The global burden of occupationally related low back pain: estimates from the Global Burden of Disease 2010 study.

OBJECTIVES: The study was part of the Global Burden of Disease 2010 study and aimed to quantify the burden arising from low back pain (LBP) due to occupational exposure to ergonomic risk factors. METHODS: Exposure prevalence was based on occupation distribution; estimates of relative risk came from a meta-analysis of relevant published literature. The work-related burden was estimated as disability-adjusted life years (DALYs). Estimates were made for each of 21 world regions and 187 countries, separately for 1990 and 2010 using consistent methods. RESULTS: Worldwide, LBP arising from ergonomic exposures at work was estimated to cause 21.7 million DALYs in 2010. The overall population attributable fraction was 26%, varying considerably with age, sex and region. 62% of LBP DALYs were in males-the largest numbers were in persons aged 35-55 years. The highest relative risk (3.7) was in the agricultural sector. The largest number of DALYs occurred in East Asia and South Asia, but on a per capita basis the biggest burden was in Oceania. There was a 22% increase in overall LBP DALYs arising from occupational exposures between 1990 and 2010 due to population growth; rates dropped by 14% over the same period. CONCLUSIONS: LBP arising from ergonomic exposures at work is an important cause of disability. There is a need for improved information on exposure distributions and relative risks, particularly in developing countries.

Exercise DVD effect on musculoskeletal disorders in professional orchestral musicians.

BACKGROUND: Professional musicians report a high prevalence of performance-related musculoskeletal disorders (PRMDs). Excessive muscle tension and fatigue have been reported as important factors contributing to PRMDs. AIMS: To evaluate feasibility and effectiveness of a specific exercise programme delivered via a digital video disc (DVD) targeting PRMDs and associated risk factors. METHODS: Volunteers from eight Australian symphony orchestras undertook two or more sessions per week over 12 weeks. Questionnaires were administered pre- and post-intervention with items including the frequency and severity of PRMDs, perceived exertion during different playing situations, per formance effects of the DVD and satisfaction rates. Musicians who had also participated in an equivalent face-to-face programme prior to this DVD trial compared the two interventions. RESULTS: One hundred and forty-four out of 576 musicians volunteered (25% uptake), and 50 participants completed a mean 2.1 (SD 0.42) sessions over the 12 week period (41% compliance). PRMD frequency and severity were significantly reduced post-intervention (P < 0.01). Participants reported benefits of the DVD on strengthening muscles, increasing ease of movement and improving flexibility related to playing. Despite this, perceived exertion levels during private practice, rehearsal and performance remained the same (not significant). Seventy-eight per cent of participants scored their overall experience of the use of the DVD as good or excellent. Owing to its convenience and detailed exercise demonstrations, the DVD was rated as better or much better overall than the face-to-face classes by 55% of participants who had experienced both. CONCLUSIONS: An exercise DVD was well received and appeared to be effective, convenient and safe in managing occupational-specific musculoskeletal disorders in musicians.

A MODEL FOR THE TEAR FILM AND OCULAR SURFACE TEMPERATURE FOR PARTIAL BLINKS.

In this paper, we investigate the dynamics of tear film and the associated temperature variation for partial blinks. We investigate the mechanism of fluid supply during partial blink cycles, and compare the film thickness with observation in vivo. We find that varying the thickness of the fluid layer beneath the moving upper lid improves the agreement for the in vivo measurement of tear film thickness after a half blink. By examining the flux of the fluid, we provide an explanation of this assumption. We also investigate the temperature dynamics both at the ocular surface and inside the simulated anterior chamber. Our simulation results suggest that the ocular surface temperature readjusts rapidly to normal temperature distribution after partial blinks.

High incidence and costs for anterior cruciate ligament reconstructions performed in Australia from 2003-2004 to 2007-2008: time for an anterior cruciate ligament register by Scandinavian model?

The aim of this paper was to provide a descriptive epidemiology of anterior cruciate ligament (ACL) reconstructions in Australia. Data on all ACL reconstructions were collected from July 1, 2003 till June 30, 2008. Main outcome measures were the incidence of ACL reconstructions for Australia, per age group, sex and sport, including estimates of direct costs. There were 50 187 ACL reconstructions over the 5-year period studied. The population-based incidence of ACL reconstructions per 100 000 person-years was 52.0 [95% confidence intervals (CI): 51.6; 52.5], higher than previously published incidences from other western countries (Scandinavia 32-38). The population incidence rose rapidly through adolescence and early adulthood and then gradually declined. Males had a higher population incidence than females. Skiing had the highest incidence of ACL reconstructions per 100 000 person-years, followed by Australian rules football, rugby, netball and soccer. The total estimated hospital costs associated with ACL reconstruction surgery were over A$75 million (€45 million) per year. Further research is necessary to examine the causes for the higher population incidence of ACL reconstructions in Australia compared with other countries. The establishment of a national register of ACL injuries, similar to those developed in Scandinavia should be considered.

Prevalence of velopharyngeal insufficiency in woodwind and brass students.

BACKGROUND: Velopharyngeal insufficiency (VPI) is a disorder in which air leaks out through the nose, reducing performance quality and capacity in wind and brass players. There have been limited studies on the prevalence of this potentially career-threatening disorder. AIMS: To identify the prevalence of VPI in a sample of conservatorium level woodwind and brass student instrumentalists in Australia. METHODS: Wind and brass students from four music institutions were recruited by email invitation to complete an online survey. Results from 77 musicians were analysed for their knowledge and experience of VPI. Musicians who had experienced VPI provided information on the characteristics, symptoms and treatment or advice sought for the disorder. RESULTS: Of the 77 musicians included in the analysis, 44% had heard of VPI, 30% were aware of other musicians who had experienced VPI and 39% had personally experienced VPI. CONCLUSIONS: The results suggest that VPI may be a common occurrence in wind and brass players. Informal discussions with colleagues and music teachers also suggest that VPI is a frequent phenomenon. This group of musicians represents the largest sample surveyed about VPI to date.

Memory metamaterials.

The resonant elements that grant metamaterials their distinct properties have the fundamental limitation of restricting their useable frequency bandwidth. The development of frequency-agile metamaterials has helped to alleviate these bandwidth restrictions by allowing real-time tuning of the metamaterial frequency response. We demonstrate electrically controlled persistent frequency tuning of a metamaterial, which allows the lasting modification of its response by using a transient stimulus. This work demonstrates a form of memory capacitance that interfaces metamaterials with a class of devices known collectively as memory devices.

Rural and remote obstetric care close to home: program description, evaluation and discussion of Sioux Lookout Meno Ya Win Health Centre obstetrics.

PROBLEM BEING ADDRESSED: Aboriginal and non-Aboriginal women in rural and remote settings struggle to access obstetric care close to home. Objective of the program: To deliver a full range of modern and safe obstetric care to 28 remote Aboriginal communities served by rural-based health care. PROGRAM DESCRIPTION: Rural family physicians provide intrapartum, cesarean delivery and anesthesia services to 350 rural, primarily Aboriginal women in a collegial, supportive environment. CONCLUSION: Rural and remote obstetric services need support before they fail. Patient volume, remote location and organizational culture are key elements. Evidence teaches us that outcomes are best when women deliver closer to home.

An overset grid method for the study of reflex tearing.

We present an overset grid method to simulate the evolution of human tear film thickness subject to reflex tearing. The free-surface evolution is governed by a single fourth-order non-linear equation derived from lubrication theory with specified film thickness and volume flux at each end. The model arises from considering the limiting case where the surfactant is strongly affecting the surface tension. In numerical simulations, the overset grid is composed of fine boundary grids near the upper and lower eyelids to capture localized capillary thinning referred to as 'black lines' and a Cartesian grid covers the remaining domain. Numerical studies are performed on a non-linear test problem to confirm the accuracy and convergence of the scheme. The computations on the tear film model show qualitative agreement with in vivo tear film thickness measurements. Furthermore, the role of the black lines in the presence of tear supply from the lid margins, reflex tearing, was found to be more subtle than a barrier to tear fluid flow between the anterior of the eye and the meniscus at the lid margin. During reflex tearing, tears may flow through the region normally containing the black line and drift down over the cornea under the influence of gravity.

Single-equation models for the tear film in a blink cycle: realistic lid motion.

We consider model problems for the tear film over multiple blink cycles that utilize a single equation for the tear film; the single non-linear partial differential equation that governs the film thickness arises from lubrication theory. The two models that we consider arise from considering the absence of naturally occurring surfactant and the case when the surfactant is strongly affecting the surface tension. The film is considered on a time-varying domain length with specified film thickness and volume flux at each end; only one end of the domain is moving, which is analogous to the upper eyelid moving with each blink. Realistic lid motion from observed blinks is included in the model with end fluxes specified to more closely match the blink cycle than those previously reported. Numerical computations show quantitative agreement with in vivo tear film thickness measurements under partial blink conditions. A transition between periodic and non-periodic solutions has been estimated as a function of closure fraction and this may be a criterion for what is effectively a full blink according to fluid dynamics.

The contribution of occupational risks to the global burden of disease: summary and next steps.

BACKGROUND: The Comparative Risk Assessment (CRA) project of the World Health Organization (WHO) assessed worldwide mortality and morbidity in the year 2000 resulting from exposures to selected occupational hazards. This article summarizes findings of the WHO CRA project, presents the estimates of the International Labor Organization (ILO) for total deaths due to workplace risks, and calls for action. OBJECTIVES: Global burden estimates and counts of deaths assist ministers and other decision and policy makers to make informed decisions and to take action regarding risk reduction. METHODS: The WHO CRA methodology combined the proportions of the population exposed to five occupational hazards (excluding numerous risks due to inadequate global data) with relative risk measures to estimate attributable fractions of the selected health outcomes for both morbidity and mortality. ILO estimates of total numbers of global work-related injury deaths apply national fatality rates to employment data for the particular country; for disease deaths ILO uses an attributable risk approach. RESULTS: In 2000, the selected occupational risk factors were responsible worldwide for 37% of back pain, 16% of hearing loss, 13% of chronic obstructive pulmonary disease (COPD), 11% of asthma, 8% of injuries, 9% of lung cancer and 2% of leukemia, and about 100% of pneumoconioses and mesothelioma. These selected risks at work resulted in the loss of about 24 million years of healthy life and caused 850,000 deaths worldwide, about 40% of the ILO estimate of 2.2 million total deaths. CONCLUSIONS: These global and regional analyses have identified areas where specific preventive actions are required.

Comparison of fatalities from work related motor vehicle traffic incidents in Australia, New Zealand, and the United States.

OBJECTIVE: To compare the extent and characteristics of motor vehicle traffic incidents on public roads resulting in fatal occupational injuries in Australia, New Zealand (NZ), and the United States (US). DESIGN AND SETTING: Information came from separate data sources in Australia (1989--92), NZ (1985--98), and the US (1989--92). METHODS: Using data systems based on vital records, distributions and rates of fatal injuries resulting from motor vehicle traffic incidents were compared for the three countries. Common inclusion criteria and occupation and industry classifications were used to maximize comparability. RESULTS: Motor vehicle traffic incident related deaths accounted for 16% (NZ), 22% (US), and 31% (Australia) of all work related deaths during the years covered by the studies. Australia had a considerably higher crude rate (1.69 deaths/100,000 person years; 95% confidence interval (95% CI) 1.54 to 1.83) compared with both NZ (0.99; 95% CI 0.85 to 1.12) and the US (0.92; 95% CI 0.89 to 0.94). Industry distribution differences accounted for only a small proportion of this variation in rates. Case selection issues may have accounted for some of the remainder, particularly in NZ. In all three countries, male workers, older workers, and truck drivers were at higher risk. CONCLUSIONS: Motor vehicle traffic incidents are an important cause of work related death of workers in Australia, NZ, and the US. The absolute rates appear to differ between the three countries, but most of the incident characteristics were similar. Lack of detailed data and inconsistencies between the data sets limit the extent to which more in-depth comparisons could be made.

Resistance exercise as a countermeasure to disuse-induced bone loss.

During spaceflight, skeletal unloading results in loss of bone mineral density (BMD). This occurs primarily in the spine and lower body regions. This loss of skeletal mass could prove hazardous to astronauts on flights of long duration. In this study, intense resistance exercise was used to test whether a training regimen would prevent the loss of BMD that accompanies disuse. Nine subjects (5 men, 4 women) participated in a supine maximal resistance exercise training program during 17 wk of horizontal bed rest. These subjects were compared with 18 control subjects (13 men, 5 women) who followed the same bed rest protocol without exercise. Determination of treatment effect was based on measures of BMD, bone metabolism markers, and calcium balance obtained before, during, and after bed rest. Exercisers and controls had significantly (P < 0.05) different means, represented by the respective following percent changes: lumbar spine BMD, +3% vs. -1%; total hip BMD, +1% vs. -3%; calcaneus BMD, +1% vs. -9%; pelvis BMD, -0.5% vs. -3%; total body BMD, 0% vs. -1%; bone-specific alkaline phosphatase, +64% vs. 0%; alkaline phosphatase, +31% vs. +5%; osteocalcin, +43% vs. +10%; 1,25 dihydroxyvitamin D, +12% vs. -15%; parathyroid hormone intact molecule, +18% vs. -25%; and serum and ionized calcium, -1% vs. +1%. The difference in net calcium balance was also significant (+21 mg/day vs. -199 mg/day, exercise vs. control). The gastrocnemius and soleus muscle volumes decreased significantly in the exercise group, but the loss was significantly less than observed in the control group. The results indicate that resistance exercise had a positive treatment effect and thus might be useful as a countermeasure to prevent the deleterious skeletal changes associated with long-duration spaceflight.

Review of the role of alcohol in drowning associated with recreational aquatic activity.

OBJECTIVE AND DESIGN: To assess the role of alcohol in drowning associated with recreational aquatic activity by reviewing the English language literature published up to October 2003. RESULTS: Alcohol is widely used in association with recreational aquatic activity in the United States, but there is minimal information regarding the extent of use elsewhere. A priori and anecdotal evidence suggests that alcohol is an important risk factor for drowning associated with recreational aquatic activity. Specific studies provide good evidence supporting this, but the extent of increased risk associated with alcohol use, and the attributable risk due to alcohol use, is not well characterised. Drowning appears to be the overwhelming cause of death associated with recreational aquatic activity with alcohol detected in the blood in 30%-70% of persons who drown while involved in this activity. The few relevant studies on degree of increased risk suggest persons with a blood alcohol level of 0.10 g/100 ml have about 10 times the risk of death associated with recreational boating compared with persons who have not been drinking, but that even small amounts of alcohol can increase this risk. The population attributable risk seems to be in the range of about 10%-30%. CONCLUSIONS: Alcohol consumption significantly increases the likelihood of immersions resulting in drowning during aquatic activities. However, more information is required if appropriate prevention activities are to be planned, initiated, and evaluated. This includes better information on alcohol use, and attitudes to alcohol use, in association with recreational aquatic activity, and the nature and extent of increased risk associated with alcohol use. Evaluation of interventions is also needed.

Monitoring sweat calcium using skin patches.

The purpose of this study was to determine whether a simple noninvasive sweat collection method using skin patches would be useful in monitoring sweat Ca and to determine changes in dermal Ca loss during a bed rest study testing a resistive exercise countermeasure. The study showed that the technique was highly reproducible: the mean intra-subject variation approached zero and the inter-individual variability (%CV) varied from 18% to 32% for the three anatomical regions (arm, chest, and back) tested. There was less than 10% difference in sweat Ca excretion from different skin regions within the same individual at a given time point. A calculated estimate of total body sweat excretion for 12 bed rest subjects was 35 +/- 4 mg/day (mean +/- SE), close to published whole body measurements. Bed rest testing showed no significant differences with or without exercise when conducted in a temperature-controlled environment. We conclude that the skin patch technique is useful for monitoring changes in sweat Ca.

Isospectral shapes with Neumann and alternating boundary conditions.

The isospectrality of a well-known pair of shapes constructed from two arrangements of seven congruent right isosceles triangles with the Neumann boundary condition is verified numerically to high precision. Equally strong numerical evidence for isospectrality is presented for the eigenvalues of this standard pair in new boundary configurations with alternating Dirichlet and Neumann boundary conditions along successive edges. Good agreement with theory is obtained for the corresponding spectral staircase functions. Strong numerical evidence is also presented for isospectrality in an example of a different pair of shapes whose basic building-block triangle is not isosceles. Some possible confirmatory experiments involving fluids are suggested.