Sparse interleaved sampling for high resolution focal construct geometry X-ray tomography

We demonstrate interleaved sampling by multiplexing conical subshells within the tomosynthesis and raster scanning a phantom through a 150 kV shell X-ray beam. Each view comprises pixels sampled on a regular 1 mm grid, which is then upscaled by padding with null pixels before tomosynthesis. We show that upscaled views comprising 1% sample pixels and 99% null pixels increase the contrast transfer function (CTF) computed from constructed optical sections from approximately 0.6 line pairs/mm to 3 line pairs/mm. The driver of our method is to complement work concerning the application of conical shell beams to the measurement of diffracted photons for materials identification. Our approach is relevant to time-critical, and dose-sensitive analytical scanning applications in security screening, process control and medical imaging.

POS1314 VALIDATION OF A PEDIATRIC-SPECIFIC ULTRASOUND SCORING SYSTEM FOR THE EVALUATION OF WRIST, FINGER, AND ANKLE SYNOVITIS

Background

Juvenile Idiopathic Arthritis (JIA) is the most common chronic rheumatic disease in children. Clinical evaluation of arthritis is a subjective measurement. Musculoskeletal ultrasound (MSUS) is increasingly being utilized in children. In order to provide objective assessments of arthritis, reliable and validated MSUS scoring systems are needed. Recently, a joint-specific scoring system for the assessment of arthritis of the pediatric ankle, wrist and finger joints were proposed[1, 2].

Objectives

This study aims to further validate the MSUS scoring system for the assessment of finger, wrist, and ankle arthritis

Methods

JIA patients with finger, wrist, and ankle arthritis as per expert clinician evaluation are eligible for this study. A comprehensive wrist, ankle, and finger (2-5th metacarpal and 2-5th proximal interphalangeal joints) MSUS examination by an American College of Rheumatology MSUS certified pediatric rheumatologist is performed an all enroll subjects. MSUS are scored using the semiquantitative (grade 0 to 3) scoring systems previously proposed. A subset of participants receives an MRI with contrast of the targeted joint immediately after MSUS performance. MRI findings are read for presence of synovitis, tendonitis and enthesitis by a pediatric radiologist with expertise on musculoskeletal imaging. For the analysis of the current report, MRIs were classified as having presence or absence of findings of JIA disease based on the pediatric radiologist expert opinion. MSUS were classified as normal (grade 0 and 1) or abnormal (grade 2 and 3). Cohen’s Kappa Coefficient was used to assess the level of agreement between MSUS (normal and abnormal) and MRI with contrast (absence or presence of disease) for each targeted joint. Tetrachoric Correlation was used to assess the strength of the association. Fisher’s Exact test was used to determine statistical significance at p < 0.05 level.

Results

A total of 52 children aged 2 – 18 years old have been enrolled in this study. To date 20 MSUS of the finger(s), 33 MSUS of the wrist, and 43 MSUS of the ankle joints have been collected. Three MRI of the 2-5 fingers (12 fingers total), 6 MRI of the wrist, and 5 MRI of ankle have been obtained through the study. Preliminary results of this effort reveal that for the ankle joint there is moderate agreement (Kappa coefficient 0.53 (confidence interval (CI)=0.14-0.92)) between MRI and US and a strong positive tetrachoric correlation (0.79) (p = 0.03). While the Kappa coefficient for comparing MRI and US finding on wrist joint indicated moderate agreement (Kappa 0.62 [0.15-1.00]) with a strong tetrachoric correlation (0.83) the Fisher’s exact test indicated a trend rather than statistically significant results (p = 0.07). The Kappa coefficient for MCPs and PIPs joints indicated strong agreement between MRI and US (Kappa 0.83 [CI=0.52-1.00] and 0.80 [CI=0.43-1.00] respectively) and were supported by an almost perfect Tetrachoric Correlation of 0.99 (p < 0.01). We anticipate to complete enrollment of subjects by the summer of 2022. Analysis of collected data is underway.

Conclusion

The strong to moderate association of MSUS with contrast-enhanced MRI, suggest that MSUS can provide an objective and accurate assessment of ankle, wrist and finger arthritis at the bedside. Further refinement and validation of these pediatric-specific MSUS scoring systems may support the use of MSUS as a clinical tool and outcome measure in JIA.

References

[1]Vega-Fernandez P, D.R.D., Oberle E, Bukulmez H, Lin C, Shenoi S, Thatayatikom A, Woolnough L, Corbin K, Benham H, Brunner E, Henrickson M, Ballenger L, Haro S, Schutt C, Proulx-Gauthier J, Janow G, Altaye M, Cassedy A, Roth J, Ting T., Novel Ultrasound Image Acquisition Protocol and Scoring System for the Pediatric Ankle [abstract]. Arthritis Rheumatol, 2020. 72.

[2]Vega-Fernandez, P., et al., The MUSICAL pediatric ultrasound examination - a comprehensive, reliable, time efficient assessment of synovitis. Arthritis Care Res (Hoboken), 2021.

Acknowledgements

Project supported by the Center for Clinical & Translational Science & Training (CCTST) at the University of Cincinnati funded by the National Institutes of Health (NIH) Clinical and Translational Science Award (CTSA) program, grant 2UL1TR001425-05A1 and KL2 (2KL2TR001426-05A); and a Diversity and Health Disparities Award from the Cincinnati Children’s Hospital Medical Center.

Disclosure of Interests

None declared

Organic synthesis associated with serpentinization and carbonation on early Mars

Water-rock interactions are relevant to planetary habitability, influencing mineralogical diversity and the production of organic molecules. We examine carbonates and silicates in the martian meteorite Allan Hills 84001 (ALH 84001), using colocated nanoscale analyses, to characterize the nature of water-rock reactions on early Mars. We find complex refractory organic material associated with mineral assemblages that formed by mineral carbonation and serpentinization reactions. The organic molecules are colocated with nanophase magnetite; both formed in situ during water-rock interactions on Mars. Two potentially distinct mechanisms of abiotic organic synthesis operated on early Mars during the late Noachian period (3.9 to 4.1 billion years ago).

Coastal flood risk within a peri-urban area: Sussex Inlet district, SE Australia

The peri-urban interface (PUI) exhibits characteristic qualities of both urban and rural regions, and this complexity has meant that risk assessments and long-term planning for PUI are lagging, despite these areas representing new developing settlement frontiers. This study aims to address this knowledge gap by modifying an existing approach to quantify and assess flood risk. The risk triangle framework was used to map exposure, vulnerability and biophysical variables; however, in a novel application, the risk triangle framework was adapted by presuming that there is a variation in the degree of exposure, vulnerability and biophysical variables. Within Australia and globally, PUIs are often coastal, and flood risk associated with rainfall and coastal inundation poses considerable risk to communities in the PUI; these risks will be further exacerbated should projections of increasing frequency of extreme rainfall events and accelerating sea-level rise eventuate. An indicator-based approach using the risk triangle framework that maps flood hazard, exposure and vulnerability was used to integrate the biophysical and socio-economic flooding risk for communities in PUI of the St Georges Basin and Sussex Inlet catchments of south-eastern Australia. Integrating the flood risk triangle with future scenarios of demographic and climate change, and considering factors that contribute to PUI flood risk, facilitated the identification of planning strategies that would reduce the future rate of increase in flood risk. These planning strategies are useful for natural resource managers and land use planners across Australia and globally, who are tasked with balancing socio-economic prosperity for a changing population, whilst maintaining and enhancing ecosystem services and values. The indicator-based approach used in this study provides a cost-effective first-pass risk assessment and is a valuable tool for decision makers planning for flood risk across PUIs in NSW and globally.

Mangrove sinkholes (cenotes) of the Yucatan Peninsula, a global hotspot of carbon sequestration

Mangroves are among the most carbon-dense ecosystems on the planet. The capacity of mangroves to store and accumulate carbon has been assessed and reported at regional, national and global scales. However, small-scale sampling is still revealing 'hot spots' of carbon accumulation. This study reports one of these hotspots, with one of the largest-recorded carbon stocks in mangroves associated with sinkholes (cenotes) in the Yucatan Peninsula, Mexico. We assessed soil organic carbon (SOC) stocks, sequestration rates and carbon origin of deep peat soils (1 to 6 m). We found massive amounts of SOC up to 2792 Mg C ha-1, the highest value reported in the literature so far. This SOC is primarily derived from highly preserved mangrove roots and has changed little since its deposition, which started over 3220 years ago (±30 BP). Most cenotes are owned by Mayan communities and are threatened by increased tourism and the resulting extraction and pollution of groundwater. These hot spots of carbon sequestration, albeit small in area, require adequate protection and could provide valuable financial opportunities through carbon-offsetting mechanisms and other payments for ecosystem services.

Locally Identified Priorities for Continuous Quality Improvement (CQI) During Early Implementation of an Evidence-Based Early Childhood Home Visiting Program

The 2010 Affordable Care Act provided for evidence-based home visiting and an accompanying continuous quality improvement (CQI) process in all states and territories. This is an organizational-level study of one state's qualitative approach to CQI during early implementation, when data system infrastructure and local agency capacity were still developing. We examined the CQI topics created by local agencies and operationalized through a qualitative, strength-based CQI process. During the first 18 months, state and local site teams (n = 21) participated in 150 CQI teleconferences. We used qualitative content analysis of teleconference notes to identify issues important to sites and that could be addressed through a qualitative CQI process. Seven categories of CQI topics emerged: participant enrollment and retention; administrative infrastructure and capacity; programmatic resources and practices; community advisory boards; home visitor skill development; systems integration and strategic partnerships; and hiring home visiting staff. Sites added local nuances to frame and address CQI topics. When local sites identify their own CQI topics in early implementation, they addressed program need at multiple levels of influence. A few sites addressed individually focused topics traditional to CQI. Most often, sites engaged with institution- or community-focused topics atypical for CQI but nonetheless essential to launching a program: building skills and capacity for administrative and program implementation, and engaging with the local system of services. Oversight agencies should be prepared to address program, organization, partner or system level issues through CQI to foster program establishment. A site-centered, strength-based approach can support programs even when quantitative data are limited.

P1943Ambient temperature and seasonal effects on blood pressure in 2.6 million Australians

Background

There is evidence that blood pressure (BP) levels vary considerably from season to season, due principally to variation in ambient temperature. This gives the potential for both under- and over-treatment if BP lowering medications are not varied seasonally, but is not acknowledged in clinical guidelines. We will describe the seasonal variation in BP and assess the association between systolic blood pressure (SBP) and outdoor maximum ambient temperature in Australia.

Methods

The primary care data is an extract from MedicineInsight, a national general practice data program developed and managed by NPS MedicineWise, which extracts deidentified data from almost 10% of all Australian general practices. We included patients aged 30–90 years with at least one BP measure recorded from 1 Jan 2010 to 1 Aug 2017. Australian Bureau of Meteorology daily max temperature is linked by matching observation dates and location to nearest weather station. Decomposition of the mean will determine seasonal variation. Multiple linear regression was used to estimate the associations between max temperature and SBP with adjustment for age, sex, socioeconomic index, current smoking, comorbidities, BP lowering medication use, lipid lowering medication use and year of BP measurement.

Results

The study population includes 2.6 million people, mean age 55 years (standard deviation [SD] 16.3). Fifty-five percent are female, over a third of the cohort reside in New South Wales, and 62.4% reside in major Australian cities. The mean (SD) temperature was 23°C (6.6).

There was a mean (SD) of 7 (11.4) BP measurements per person over the study period, median 3 measures (interquartile range 1–8). A quarter had a history of hypertension, 8% had a history of cardiovascular disease, and 8% had a history of diabetes. Twenty-six percent had at least one prescription for BP lowering therapy.

The average monthly SBP for the cohort demonstrated strong seasonal variation with higher values in winter. The population mean varies by 3mmHg SBP between seasons across Australia, ranging from 1.7mmHg in the Northern Territory to 3.5mmHg in South Australia (range of mean maximum temperature 3°C [30–33] and 14°C [15–29] for the capital cities respectively). Each 10°C increase in max outdoor temperature was associated with a 1.8mmHg [95% CI 1.80–1.83] lower mean SBP. The proportion of people with SBP>140mmHg varied by season, irrespective of age, sex and use of BP lowering treatment. For example, among those treated control rates varied between 70 and 81%, and among those not treated between 78 and 85% (Figure).

Blood pressure seasonality in Australia

Conclusions

BP control rates vary considerably by season. These findings have implications for the reliable diagnosis of hypertension, and suggest seasonal adjustments in treatment should be considered for some patients. The clinical and public health relevance of this phenomenon is expected to increase with increasing climate variability.

Acknowledgement/Funding

National Health and Medical Research Council Australia, National Heart Foundation Australia

Organic synthesis on Mars by electrochemical reduction of CO2

The sources and nature of organic carbon on Mars have been a subject of intense research. Steele et al. (2012) showed that 10 martian meteorites contain macromolecular carbon phases contained within pyroxene- and olivine-hosted melt inclusions. Here, we show that martian meteorites Tissint, Nakhla, and NWA 1950 have an inventory of organic carbon species associated with fluid-mineral reactions that are remarkably consistent with those detected by the Mars Science Laboratory (MSL) mission. We advance the hypothesis that interactions among spinel-group minerals, sulfides, and a brine enable the electrochemical reduction of aqueous CO₂ to organic molecules. Although documented here in martian samples, a similar process likely occurs wherever igneous rocks containing spinel-group minerals and/or sulfides encounter brines.

Converse Smith-Martin cell cycle kinetics by transformed B lymphocytes

Recent studies using direct live cell imaging have reported that individual B lymphocytes have correlated transit times between their G1 and S/G2/M phases. This finding is in contradiction with the influential model of Smith and Martin that assumed the bulk of the total cell cycle time variation arises in the G1 phase of the cell cycle with little contributed by the S/G2/M phase. Here we extend these studies to examine the relation between cell cycle phase lengths in two B lymphoma cell lines. We report that transformed B lymphoma cells undergo a short G1 period that displays little correlation with the time taken for the subsequent S/G2/M phase. Consequently, the bulk of the variation noted for total division times within a population is found in the S/G2/M phases and not the G1 phase. Models that reverse the expected source of variation and assume a single deterministic time in G1 followed by a lag + exponential distribution for S/G2/M fit the data well. These models can be improved further by adopting two sequential distributions or by using the stretched lognormal model developed for primary lymphocytes. We propose that shortening of G1 transit times and uncoupling from other cell cycle phases may be a hallmark of lymphocyte transformation that could serve as an observable phenotypic marker of cancer evolution.

Global patterns of care in advanced stage mycosis fungoides/Sezary syndrome: a multicenter retrospective follow-up study from the Cutaneous Lymphoma International Consortium

BACKGROUND

Advanced-stage mycosis fungoides (MF)/Sézary syndrome (SS) patients are weighted by an unfavorable prognosis and share an unmet clinical need of effective treatments. International guidelines are available detailing treatment options for the different stages but without recommending treatments in any particular order due to lack of comparative trials. The aims of this second CLIC study were to retrospectively analyze the pattern of care worldwide for advanced-stage MF/SS patients, the distribution of treatments according to geographical areas (USA versus non-USA), and whether the heterogeneity of approaches has potential impact on survival.

PATIENTS AND METHODS

This study included 853 patients from 21 specialist centers (14 European, 4 USA, 1 each Australian, Brazilian, and Japanese).

RESULTS

Heterogeneity of treatment approaches was found, with up to 24 different modalities or combinations used as first-line and 36% of patients receiving four or more treatments. Stage IIB disease was most frequently treated by total-skin-electron-beam radiotherapy, bexarotene and gemcitabine; erythrodermic and SS patients by extracorporeal photochemotherapy, and stage IVA2 by polychemotherapy. Significant differences were found between USA and non-USA centers, with bexarotene, photopheresis and histone deacetylase inhibitors most frequently prescribed for first-line treatment in USA while phototherapy, interferon, chlorambucil and gemcitabine in non-USA centers. These differences did not significantly impact on survival. However, when considering death and therapy change as competing risk events and the impact of first treatment line on both events, both monochemotherapy (SHR = 2.07) and polychemotherapy (SHR = 1.69) showed elevated relative risks.

CONCLUSION

This large multicenter retrospective study shows that there exist a large treatment heterogeneity in advanced MF/SS and differences between USA and non-USA centers but these were not related to survival, while our data reveal that chemotherapy as first treatment is associated with a higher risk of death and/or change of therapy and thus other therapeutic options should be preferable as first treatment approach.

Realizing the promise of The Partnership for Maternal, Newborn and Child Health

Reflecting on Storeng and Béhague ("Lives in the balance": the politics of integration in the Partnership for Maternal, Newborn and Child Health. Health Policy and Planning Storeng and Béhague (2016).) historical ethnography of the Partnership for Maternal, Newborn and Child Health (PMNCH), this commentary provides a more current account of PMNCH's trajectory since its inception in 2005. It highlights PMNCH's distinct characteristics and how it is positioned to play an instrumental role in the current global health landscape.

Predictors of older drivers' involvement in rapid deceleration events

Rapid deceleration occurs when substantial force slows the speed of a vehicle. Rapid deceleration events (RDEs) have been proposed as a surrogate safety measure. As there is concern about crash involvement of older drivers and the effect of age-related declining visual and cognitive function on driving performance, we examined the relationship between RDEs and older driver's vision, cognitive function and driving confidence, using naturalistic driving measures. Participants aged 75 to 94 years had their vehicle instrumented for 12 months. To minimise the chance of identifying false positives, accelerometer data was processed to identify RDEs with a substantial deceleration of >750 milli-g (7.35m/s²). We examined the incidence of RDEs amongst older drivers, and how this behaviour is affected by differences in age; sex; visual function, cognitive function; driving confidence; and declines over the 12 months. Almost two-thirds (64%) of participants were involved in at least one RDE, and 22% of these participants experienced a meaningful decline in contrast sensitivity during the 12 months. We conducted regression modelling to examine associations between RDEs and predictive measures adjusted for (i) duration of monitoring and (ii) distance driven. We found the rate of RDEs per distance increased with age; although, this did not remain in the multivariate model. In the multivariate model, we found older drivers who experienced a decline in contrast sensitivity over the 12 months and those with lower baseline driving confidence were at increased risk of involvement in RDEs adjusted for distance driven. In other studies, contrast sensitivity has been associated with increased crash involvement for older drivers. These findings lend support for the use of RDEs as a surrogate safety measure, and demonstrate an association between a surrogate safety measure and a decline in contrast sensitivity of older drivers.

Towards new material biomarkers for fracture risk

Osteoporosis is a prevalent bone condition, characterised by low bone mass and increased fracture risk. Currently, the gold standard for identifying osteoporosis and increased fracture risk is through quantification of bone mineral density (BMD) using dual energy X-ray absorption (DEXA). However, the risk of osteoporotic fracture is determined collectively by bone mass, architecture and physicochemistry of the mineral composite building blocks. Thus DEXA scans alone inevitably fail to fully discriminate individuals who will suffer a fragility fracture. This study examines trabecular bone at both ultrastructure and microarchitectural levels to provide a detailed material view of bone, and therefore provides a more comprehensive explanation of osteoporotic fracture risk. Physicochemical characterisation obtained through X-ray diffraction and infrared analysis indicated significant differences in apatite crystal chemistry and nanostructure between fracture and non-fracture groups. Further, this study, through considering the potential correlations between the chemical biomarkers and microarchitectural properties of trabecular bone, has investigated the relationship between bone mechanical properties (e.g. fragility) and physicochemical material features.