Properties of the Household Food Security Survey Module Scale in Young Adults with Diabetes.

BACKGROUND: The Household Food Security Survey Module (HFSSM) was not tailored to people with chronic diseases or young adults (YAs). OBJECTIVES: We aim to evaluate whether the 18-item HFSSM meets assumptions underlying the scale among YAs with diabetes. METHODS: Data from 1887 YAs with youth-onset type 1 diabetes or type 2 diabetes were used from the SEARCH for Diabetes in Youth Study, 2016-2019, and on 925 who returned for the SEARCH Food Security Cohort Study, 2018-2021, all of whom had completed the HFSSM. Guttman scaling properties (affirmation of preceding less severe items) and Rasch model properties (probability to answer an item based on difficulty level) were assessed. RESULTS: Items 3 (balanced meals) and 6 (eating less than one should) were affirmed more frequently than expected (nonmonotonic response pattern). At 1.2%-3.5%, item nonresponse was rare among type 1 diabetes but higher among type 2 diabetes (range: 3.1%-10.6%). Items 9 (not eating the whole day) and 3 did not meet the Guttman scaling properties. Rasch modeling revealed that item 3 had the smallest difficulty parameter. INFIT indices suggested that some responses to item 3 did not match the pattern in the rest of the sample. Classifying household food insecurity (HFI) based on items 1 and 2 compared with other 2-item combinations, including item 3, revealed a substantial undercount of HFI ranging from 5% to 8% points. CONCLUSIONS: Use of the HFSSM among YAs with diabetes could potentially result in biased HFI reporting and affect estimates of HFI prevalence in this population.

Household Food Insecurity and Cognition in Youth and Young Adults with Youth-Onset Diabetes.

Objective: We evaluated the association of household food insecurity (FI) with cognition in youth and young adults with type 1 diabetes (T1D) or type 2 diabetes (T2D). Design: In this cross-sectional study, age-adjusted scores for composite Fluid Cognition, and sub-domain scores for Receptive Language and Inhibitory Control and Attention, were modeled stratified by diabetes-type using linear regression, with FI in the past year as the predictor, controlling for covariates. Tests for processing speed, inhibitory control/attention, working memory, episodic memory, and cognitive flexibility were administered to measure composite Fluid Cognition score. The NIHT-CB Picture Vocabulary Test was used to assess Crystallized Cognition score and rapid identification of congruent versus noncongruent items were used to assess Inhibitory Control and Attention score. Setting: The SEARCH for Diabetes in Youth study, representative of 5 U.S. states. Participants: Included 1574 youth and young adults with T1D or T2D, mean age of 21 years, mean diabetes duration of 11 years, 51% non-Hispanic white, and 47% had higher HbA1c levels (>9% HbA1c). Results: Approximately 18% of the 1,240 participants with T1D and 31% of the 334 with T2D experienced FI. The food-insecure group with T1D had a lower composite Fluid Cognition score (ß= -2.5, 95% confidence interval (CI)= -4.8, -0.1) and a lower Crystallized Cognition score (ß= -3.4, CI= -5.6, -1.3) than food-secure peers. Findings were attenuated to non-significance after adjustment for demographics. Among T2D participants, no associations were observed. In participants with T1D effect modification by glycemic levels were found in the association between FI and composite Fluid Cognition score but adjustment for socioeconomic characteristics attenuated the interaction (p=0.0531). Conclusions: Food-insecure youth and young adults with T1D or T2D did not have different cognition compared to those who were food-secure after adjustment for confounders. Longitudinal research is needed to further understand relations amongst these factors.

How can scope of practice be described and conceptualised in medical and health professions? A systematic review for scoping and content analysis.

BACKGROUND: The term scope of practice (SOP) refers to the limits of a health professional's knowledge, skills and experience and reflects all tasks and activities they undertake within the context of their professional role. Inconsistency in definitions of SOP contributes to uncertainty and confusion regarding professional practice boundaries and potentially impacts societal access to safe, effective and efficient healthcare options. The aim of this paper is to understand the conceptual diversity that may exist in terminology used to describe medical, nursing/midwifery and allied health SOP within an Australian practice context exemplar. METHODS: A systematic review for scoping and content analysis of SOP definitions and concepts, involving inductive thematic analysis and synthesis of published and grey literature. RESULTS: The initial search strategy yielded 11,863 hits, of which 379 were suitable for inclusion. Data coding identified various SOP terms and definitions and the emergence of six, conceptual elements underpinning the theoretical construct. These were subsequently proposed as a preliminary conceptual model ('Solar') to explain how the six conceptual elements may be applied across various professions, clinical settings and jurisdictions to better understand and address current and evolving SOP issues. CONCLUSION: The findings of this study highlight limited consistency in SOP definitions and terminology within a single jurisdiction, and the conceptual complexity of the underlying theoretical construct. Further research is required to build on the proposed 'Solar' conceptual model and create a universal SOP definition across jurisdictions, to enhance understanding of the importance of SOP to workforce policy, clinical governance, service models and patient outcomes.

The SSLepR mutant rat represents a novel model to study obesity-induced renal injury before puberty.

Prepubertal obesity (PPO) has emerged as a major health problem over the past few decades and is a risk factor for the development of proteinuria. The current study investigated whether the development of renal injury in the obese SSLepR mutant strain occurs before puberty. When determining the temporal changes in serum sex hormones in female and male SS and SSLepR mutant rats between 4 and 10 wk of age, we only observed significant increases in estradiol and testosterone levels in female and male SS rats at 10 wk of age than at 4 wk of age. The results suggest that studying both strains between 4 and 8 wk of age is appropriate to study the effects of PPO on renal injury in this model. Proteinuria was significantly higher in SSLepR mutant rats as opposed to the values observed in SS rats at 8 wk of age, and we did not observe any sex differences in proteinuria in either strain. The kidneys from the SSLepR mutant rats displayed significant glomerular and tubular injury and renal fibrosis versus the values measured in SS rats without any sex differences. Overall, we observed increased immune cell infiltration in the kidneys from SSLepR mutant rats compared with SS rats. Interestingly, female SSLepR mutant rats displayed significant increases in not only M1 macrophages (proinflammatory) but also M2 macrophages (anti-inflammatory) versus male SSLepR mutant rats. These results suggest the SSLepR mutant rat may be a useful model to study early progression of obesity-related renal injury before the onset of puberty.

Estimating the impact of work difficulties, work self-efficacy and work psychological safety on MS-related work productivity loss.

BACKGROUND: A comprehensive understanding of factors associated with multiple sclerosis (MS)-related work productivity loss will inform targeted interventions. We have previously shown the strong impact of symptom severity on MS-related work productivity loss. However, the effect of work difficulties, work self-efficacy and work psychological safety is yet to be well evaluated in this context. OBJECTIVES: This study evaluates the association between work difficulties, work self-efficacy and work psychological safety, and MS-related presenteeism, absenteeism and total work productivity loss. METHODS: We analysed data from employed participants of the Australian MS Longitudinal Study (AMSLS) who took part in both the 2015 Medication and Disease Course survey, and 2015 Employment survey (n = 744). Data were analysed using Cragg Hurdle regression models. RESULTS: We found that low workplace self-esteem, interpersonal difficulties at work and work self-efficacy were associated with total work productivity loss. In a multivariable model, a 10-unit decrease in workplace self-esteem, increase in interpersonal difficulties at work and 5-unit increase in work self-efficacy were independently associated with a 3.75% increase, 2.89% increase and 3.36% reduction in total work productivity loss, respectively. When separating total work productivity loss in presenteeism and absenteeism, stronger effects were seen for presenteeism than absenteeism. Surprisingly, work psychological safety was not associated with MS-related work productivity loss. CONCLUSION: Work psychosocial well-being such as self-confidence at work, work self-efficacy and interpersonal difficulties at work are crucial factors governing work productivity in people with MS (PwMS). Multidisciplinary support team assistance of PwMS in symptom self-care, skills around effective communication about MS in the workplace, the psychological impact of work and the modification of work demands may positively influence the employment outcomes.

Measuring atmospheric turbulence along folded paths using a laser-illuminated differential image motion monitor.

A laser-illuminated differential image motion monitor (DIMM) is presented that is able to measure the atmospheric coherence length r 0 along horizontal ground paths. This is accomplished by implementing a mono-static setup in which the transmitter and receiver are co-located and transmit to a retroreflective target. The impact of propagating along a folded path through the same volume of turbulent atmosphere is investigated in detail and the overall impact to angle-of-arrival measurements described. In addition, an outdoor test campaign was conducted to validate the findings by testing two commercial scintillometers and the laser DIMM side by side in both bi-static and mono-static configurations. Both analytical and experimental results show that under certain conditions, folded-path propagation can be treated identically to traditional single-path propagation.

Numerical simulation of a large area scintillometer and laser differential image motion monitor.

Measurements of atmospheric turbulence along a path can be quantified by scintillometers and differential image motion monitors (DIMMs). The two instruments often measure different levels of turbulence, sometimes varying by nearly an order of magnitude. A high-fidelity numerical simulation was leveraged to assess the measurement performance of both a scintillometer and a DIMM system. When a non-ideal detector is combined with range-dependent turbulence, significant differences between the scintillometer and DIMM are observed. The difference in measurements obtained with the numerically simulated scintillometer and DIMM was consistent with those observed in side-by-side measurements with the instruments.

Interferon γ neutralization reduces blood pressure, uterine artery resistance index, and placental oxidative stress in placental ischemic rats.

Preeclampsia (PE) is characterized by maternal hypertension, intrauterine growth restriction, and increased cytolytic natural killer cells (cNKs), which secrete interferon γ (IFNγ). However, the precise role of IFNγ in contributing to PE pathophysiology remains unclear. Using the reduced uterine perfusion pressure (RUPP) rat model of placental ischemia, we tested the hypothesis that neutralization of IFNγ in RUPPs will decrease placental reactive oxygen species (ROS) and improve vascular function resulting in decreased MAP and improved fetal growth. On gestation day (GD) 14, the RUPP procedure was performed and on GDs 15 and 18, a subset of normal pregnant rats (NP) and RUPP rats were injected with 10 µg/kg of an anti-rat IFNγ monoclonal antibody. On GD 18, uterine artery resistance index (UARI) was measured via Doppler ultrasound and on GD 19, mean arterial pressure (MAP) was measured, animals were euthanized, and blood and tissues were collected for analysis. Increased MAP was observed in RUPP rats compared with NP and was reduced in RUPP + anti-IFNγ. Placental ROS was also increased in RUPP rats compared with NP rats and was normalized in RUPP + anti-IFNγ. Fetal and placental weights were reduced in RUPP rats, but were not improved following anti-IFNγ treatment. However, UARI was elevated in RUPP compared with NP rats and was reduced in RUPP + anti-IFNγ. In conclusion, we observed that IFNγ neutralization reduced MAP, UARI, and placental ROS in RUPP recipients. These data suggest that IFNγ is a potential mechanism by which cNKs contribute to PE pathophysiology and may represent a therapeutic target to improve maternal outcomes in PE.

Risk factors for leaving employment due to multiple sclerosis and changes in risk over the past decades: Using competing risk survival analysis.

BACKGROUND: No studies have assessed changes in employment survival in multiple sclerosis (MS) populations over recent decades, including the introduction of disease-modifying therapies (DMTs). OBJECTIVES: To evaluate factors associated with leaving employment due to MS; to assess whether the risk of leaving employment has changed over recent decades in Australia, stratified by MS phenotype. METHODS: We included 1240 participants who were working before MS diagnosis. Information on employment status, reasons for leaving employment and year of leaving were collected. Data were analysed using competing risk survival analysis. RESULTS: Males, progressive MS, lower education level and older age at diagnosis were associated with a higher sub-distribution hazard of leaving employment. Compared to the period before 2010, the sub-distribution hazard during 2010-2016 for relapsing-remitting multiple sclerosis (RRMS) was reduced by 43% (sub-distribution hazard ratio (sHR) 0.67, 95% confidence interval (CI): 0.50 to 0.90), while no significant reduction was seen for primary-progressive multiple sclerosis (PPMS) (sHR 1.25, 95% CI: 0.72 to 2.16) or secondary-progressive multiple sclerosis (SPMS) (sHR 1.37, 95% CI: 0.84 to 2.25). CONCLUSION: Males, people with progressive MS and those of lower education level were at higher risk of leaving employment. The differential changed risk of leaving employment between people with different MS phenotype after 2010 coincides with the increased usage of high-efficacy DMTs for RRMS.

Changes in multiple sclerosis symptoms are associated with changes in work productivity of people living with multiple sclerosis.

BACKGROUND: While employment rates have increased in people with multiple sclerosis (PwMS), little is known about the longitudinal trends of work productivity. OBJECTIVE: To describe the longitudinal patterns of work productivity and examine the factors associated with annual change of work productivity of PwMS. METHODS: Study participants were employed participants of the Australian MS Longitudinal Study (AMSLS) followed from 2015 to 2019 with at least two repeated measures (n = 2121). We used linear mixed models to examine if the within-individual variations in MS symptoms are associated with changes in work productivity. RESULTS: The mean annual change in work productivity between 2015 and 2019 was -0.23% (SD = 18.68%). Not the actual severity of symptoms but rather the changes in severity of symptoms that are associated with change in work productivity in the same year. In a multivariable model, every unit increase in mean annual change in 'pain and sensory symptoms', 'feelings of anxiety and depression', and 'fatigue and cognitive symptoms' were independently associated with 2.43%, 1.55% and 1.01% annual reductions in work productivity, respectively. CONCLUSION: Individual changes in work productivity are largely driven by the changes in symptom severity rather than the absolute severity. Stabilising/improving MS symptoms might improve work productivity.

Childhood Sexual Trauma and Antiretroviral Therapy Adherence: A Mixed-Methods Systematic Review.

Childhood sexual abuse (CSA) has been shown to be more prevalent among populations living with HIV. Antiretroviral therapy (ART) adherence is crucial for populations living with HIV as it significantly increases the likelihood of attaining and maintaining viral suppression. Previous findings on the association between CSA and ART adherence have been mixed. The current mixed-methods systematic review aimed to identify quantitative and qualitative studies from CINAHL, PsycInfo, PubMed, and Web of Science examining the relationship between CSA and ART adherence. Authors were also contacted if relevant data were unpublished. Studies had to be published from January 1, 2000 to April 1, 2019, written in English, and examined CSA as an exposure and ART adherence as an outcome. Four domains were combined: (1) childhood sexual abuse; (2) child; (3) antiretroviral; and (4) adherence. Eight quantitative and two qualitative studies were retained. The results showed that four quantitative studies found no association while the other four found factors such as timing of victimization, mental health and gender influenced the association between CSA and ART adherence. Themes emerging from the qualitative studies included use of ART evoking memories of CSA; CSA impacting mental health; and mental health treatment improving ART adherence. Mixed insights included the intricate links between CSA and ART adherence and the role of external factors on the relationship. ART adherence intervention programs may be needed for people who have experienced CSA. However, future studies are needed that will examine the association between CSA and ART adherence and include subgroup analyses.

RESUMEN: El abuso sexual infantil es más prevalente en personas con VIH. La adherencia a la terapia antirretroviral (TAR) es crucial para personas con VIH porque incrementa la probabilidad de alcanzar y mantener la supresión viral. Resultados previos de la asociación entre el abuso sexual infantil y la adherencia a la TAR han sido variados. El objetivo de esta revisión sistemática utilizando métodos mixtos fue identificar investigaciones cuantitativas y cualitativas en CINAHL, PsycInfo, PubMed y Web of Science que exploran la relación entre el abuso sexual infantil y la adherencia a la TAR. Contactamos a los autores si no se publicaron datos relevantes. Las investigaciones tuvieron que ser publicadas desde enero 1 de 2000 hasta abril 1 de 2019, escritas en inglés, y explorando el abuso sexual infantil como la exposición y la adherencia a la TAR como el resultado. Cuatro ámbitos fueron combinados: 1) el abuso sexual infantil; 2) el niño; 3) el antirretroviral; y 4) la adherencia. Ocho estudios cuantitativos y dos estudios cualitativos fueron retenidos. Los resultados demostraron que cuatro estudios cuantitativos no mostraron asociación mientras los otros cuatros mostraron que los factores como el momento de victimización, la salud mental y el género influyeron en la asociación entre el abuso sexual infantil y la adherencia a la TAR. Los temas emergentes de los estudios cualitativos incluyeron el uso de la TAR que evoca recuerdos del abuso sexual infantil; el abuso sexual infantil tiene un impacto en la salud mental; y el tratamiento de salud mental mejora la adherencia a la TAR. Ideas mixtas incluyeron las relaciones complejas entre el abuso sexual infantil y la adherencia a la TAR, y el papel de los factores externos en la relación. Los programas de intervención para la adherencia a la TAR, tal vez, son necesitados para las personas que tuvieron la experiencia del abuso infantil. Sin embargo, se necesitan investigaciones futuras que examinen la asociación entre el abuso sexual infantil y la adherencia a la TAR incluyendo análisis de subgrupos.

Depletion of macrophages slows the early progression of renal injury in obese Dahl salt-sensitive leptin receptor mutant rats.

Recently, we reported that obese Dahl salt-sensitive (SS) leptin receptor mutant (SSLepRmutant) rats display progressive renal injury. The present study demonstrated that the early development of renal injury in the SSLepRmutant strain is associated with an increase in the renal infiltration of macrophages compared with lean SS rats. We also examined whether depletion of macrophages with clodronate would reduce the early progression of renal injury in the SSLepRmutant strain. Four-week-old SS and SSLepRmutant rats were treated with either vehicle (PBS) or clodronate (50 mg/kg ip, 2 times/wk) for 4 wk. While the administration of clodronate did not reduce renal macrophage infiltration in SS rats, clodronate decreased macrophages in the kidneys of SSLepRmutant rats by >50%. Interestingly, clodronate significantly reduced plasma glucose, insulin, and triglyceride levels and markedly improved glucose tolerance in SSLepRmutant rats. Treatment with clodronate had no effect on the progression of proteinuria or renal histopathology in SS rats. In the SSLepRmutant strain, proteinuria was markedly reduced during the first 2 wk of treatment (159 ± 32 vs. 303 ± 52 mg/day, respectively). However, after 4 wk of treatment, the effect of clodronate was no longer observed in the SSLepRmutant strain (346 ± 195 vs. 399 ± 50 mg/day, respectively). The kidneys from SSLepRmutant rats displayed glomerular injury with increased mesangial expansion and renal fibrosis versus SS rats. Treatment with clodronate significantly decreased glomerular injury and renal fibrosis in the SSLepRmutant strain. Overall, these data indicate that the depletion of macrophages improves metabolic disease and slows the early progression of renal injury in SSLepRmutant rats.

Health inequalities are worsening in the North East of England.

BACKGROUND: The North of England, particularly the North East (NE), has worse health (e.g. 2 years lower life expectancy) and higher health inequalities compared to the rest of England. SOURCES OF DATA: We explore this over time drawing on publicly available data. AREAS OF AGREEMENT AND CONTROVERSY: Whilst overall health is improving, within-regional health inequalities are getting worse and the gap between the NE and other regions (particularly the South of England) is worsening. The gap in life expectancy is widening with substantial variation between deprived and affluent areas within the NE. Those living in the NE are more likely to have a shorter lifespan and to spend a larger proportion of their shorter lives in poor health, as well as being more likely to die prematurely from preventable diseases. GROWING POINTS: We highlight wide, and in some cases increasing, inequalities in health outcomes between the NE and the rest of England. This health disadvantage and the north-south health divide are recognized; despite this, the situation appears to be worsening over the time. AREAS TIMELY FOR DEVELOPING RESEARCH: Research to understand and reduce health inequalities is needed particularly in the NE of England where reductions could have enhanced the impact.

Comorbidities are prevalent and detrimental for employment outcomes in people of working age with multiple sclerosis.

BACKGROUND: More work is needed to understand the burden of comorbidities in people with multiple sclerosis (MS). OBJECTIVE: To assess prevalence of 30 comorbidities and impacts of comorbidities on employment outcomes in a working-aged MS cohort. METHODS: Participants were from the Australian MS Longitudinal Study (n = 929). Information on specific comorbidity was obtained (whether or not each was present, doctor-diagnosed, limited their activities and being treated). RESULTS: Comorbidities most frequently reported to limit activities were osteoarthritis (51%), migraines (40%), anxiety (33%), depression (29%) and allergies (18%). Mean MS-related work productivity loss in past 4 weeks was 1.3 days for those without comorbidities and 2.5 days for those with any comorbidity. The annual population costs of work productivity loss were highest for people with depression, allergies, anxiety, migraines and osteoarthritis. Higher number of comorbidities was associated with more work productivity loss and a higher likelihood of not working. These associations were substantially reduced after adjustment for MS symptom severity. CONCLUSIONS: Comorbidities substantially impact employment outcomes and these effects were mainly mediated through MS symptom severity. This suggests that optimal and simultaneous management of comorbidities may be a viable strategy to reduce MS symptom severity, which in turn could improve employment outcomes.

Estimating MS-related work productivity loss and factors associated with work productivity loss in a representative Australian sample of people with multiple sclerosis.

BACKGROUND: Little is known about the work productivity loss in multiple sclerosis (MS). OBJECTIVES: To quantify the MS-related work productivity loss and to compare factors associated with labour force participation and work productivity loss. METHODS: Participants were from the Australian MS Longitudinal Study. MS-related work productivity loss included absenteeism (time missed from work) and presenteeism (reduced productivity while working). Data were analysed using log-binomial and Cragg hurdle regression. RESULTS: Among 740 MS employees, 56% experienced any work productivity loss due to MS in the past 4 weeks. The mean total work productivity loss was 2.5 days (14.2% lost productive time), absenteeism 0.6 days (3.4%) and presenteeism 1.9 days (10.8%)), leading to AU$6767 (US$4985, EURO€4578) loss per person annually. Multivariable analyses showed that work productivity was determined most strongly by symptoms, particularly 'fatigue and cognitive symptoms' and 'pain and sensory symptoms', while older age, and lower education level were also predictive of not being in the labour force. CONCLUSION: MS-related presenteeism was three times higher than absenteeism, highlighting the importance of presenteeism being included in employment outcomes. The dominance of symptom severity as predictors of both work participation and productivity loss emphasises the need for improved management of symptoms.

Closing the gap: Longitudinal changes in employment for Australians with multiple sclerosis.

BACKGROUND AND OBJECTIVES: Previous studies have documented far lower employment participation rates for people with multiple sclerosis (PwMS) compared to the general population. In a large national sample of PwMS, we examined employment status, longitudinal changes in employment and the provision of modifications to work role/environment from 2010 to 2013. METHODS: Employment data were collected through the Australian MS Longitudinal Study from 2010 to 2013, with 1260 people responding to all four surveys. Employment rates were compared with the Australian general population. The survey included questions on the provision of modifications to employees' work role and work environment. RESULTS: Employment (full- and part-time) increased from 48.8% in 2010 to 57.8% in 2013, mainly due to increases in male full-time employment. The employment gap between PwMS and the general population fell from 14.3% in 2010 to 3.5% in 2013. Male employment rates, however, remain significantly lower than the general population. The majority of PwMS who required adjustments to either their work role or environment received them. CONCLUSION: The gap in employment between PwMS and the general population has substantially reduced from 2010 to 2013, with organisations responding positively to requests for work role/environment adjustments.

Evaluation of community-based continuous distribution of long-lasting insecticide-treated nets in Toamasina II District, Madagascar.

BACKGROUND: Continuous distribution of insecticide-treated nets (ITNs) is thought to be an effective mechanism to maintain ITN ownership and access between or in the absence of mass campaigns, but evidence is limited. A community-based ITN distribution pilot was implemented and evaluated in Toamasina II District, Madagascar, to assess this new channel for continuous ITN distribution. METHODS: Beginning 9 months after the December 2012 mass campaign, a community-based distribution pilot ran for an additional 9 months, from September 2013 to June 2014. Households requested ITN coupons from community agents in their village. After verification by the agents, households exchanged the coupon for an ITN at a distribution point. The evaluation was a two-stage cluster survey with a sample size of 1125 households. Counterfactual ITN ownership and access were calculated by excluding ITNs received through the community pilot. RESULTS: At the end of the pilot, household ownership of any ITN was 96.5%, population access to ITN was 81.5 and 61.5% of households owned at least 1 ITN for every 2 people. Without the ITNs provided through the community channel, household ownership of any ITN was estimated at 74.6%, population access to an ITN at 55.5%, and households that owned at least 1 ITN for 2 people at only 34.7%, 18 months after the 2012 campaign. Ownership of community-distributed ITNs was higher among the poorest wealth quintiles. Over 80% of respondents felt the community scheme was fair and simple to use. CONCLUSIONS: Household ITN ownership and population ITN access exceeded RBM targets after the 9-month community distribution pilot. The pilot successfully provided coupons and ITNs to households requesting them, particularly for the least poor wealth quintiles, and the scheme was well-perceived by communities. Further research is needed to determine whether community-based distribution can sustain ITN ownership and access over the long term, how continuous availability of ITNs affects household net replacement behaviour, and whether community-based distribution is cost-effective when combined with mass campaigns, or if used with other continuous channels instead of mass campaigns.

Lidar measurements of solid rocket propellant fire particle plumes.

This paper presents the first, to our knowledge, direct measurement of aerosol produced by an aluminized solid rocket propellant (SRP) fire on the ground. Such fires produce aluminum oxide particles small enough to loft high into the atmosphere and disperse over a wide area. These results can be applied to spacecraft launchpad accidents that expose spacecraft to such fires; during these fires, there is concern that some of the plutonium from the spacecraft power system will be carried with the aerosols. Accident-related lofting of this material would be the net result of many contributing processes that are currently being evaluated. To resolve the complexity of fire processes, a self-consistent model of the ground-level and upper-level parts of the plume was determined by merging ground-level optical measurements of the fire with lidar measurements of the aerosol plume at height during a series of SRP fire tests that simulated propellant fire accident scenarios. On the basis of the measurements and model results, the Johns Hopkins University Applied Physics Laboratory (JHU/APL) team was able to estimate the amount of aluminum oxide (alumina) lofted into the atmosphere above the fire. The quantification of this ratio is critical for a complete understanding of accident scenarios, because contaminants are transported through the plume. This paper provides an estimate for the mass of alumina lofted into the air.

Elastic behavior and platelet retraction in low- and high-density fibrin gels.

Fibrin is a biopolymer that gives thrombi the mechanical strength to withstand the forces imparted on them by blood flow. Importantly, fibrin is highly extensible, but strain hardens at low deformation rates. The density of fibrin in clots, especially arterial clots, is higher than that in gels made at plasma concentrations of fibrinogen (3-10 mg/mL), where most rheology studies have been conducted. Our objective in this study was to measure and characterize the elastic regimes of low (3-10 mg/mL) and high (30-100 mg/mL) density fibrin gels using shear and extensional rheology. Confocal microscopy of the gels shows that fiber density increases with fibrinogen concentration. At low strains, fibrin gels act as thermal networks independent of fibrinogen concentration. Within the low-strain regime, one can predict the mesh size of fibrin gels by the elastic modulus using semiflexible polymer theory. Significantly, this provides a link between gel mechanics and interstitial fluid flow. At moderate strains, we find that low-density fibrin gels act as nonaffine mechanical networks and transition to affine mechanical networks with increasing strains within the moderate regime, whereas high-density fibrin gels only act as affine mechanical networks. At high strains, the backbone of individual fibrin fibers stretches for all fibrin gels. Platelets can retract low-density gels by >80% of their initial volumes, but retraction is attenuated in high-density fibrin gels and with decreasing platelet density. Taken together, these results show that the nature of fibrin deformation is a strong function of fibrin fiber density, which has ramifications for the growth, embolization, and lysis of thrombi.

Gambling increases self-control strength in problem gamblers.

In two studies it is demonstrated that, in the short-term, slot machine gambling increases self-control strength in problem gamblers. In Study 1 (N = 180), participants were randomly assigned to either play slot machines or engage in a control task (word anagrams) for 15 min. Subsequent self-control strength was measured via persistence on an impossible tracing task. Replicating Bergen et al. (J Gambl Stud, doi: 10.1007/s10899-011-9274-9 , 2011), control condition participants categorized as problem gamblers persisted for less time than did lower gambling risk participants. However, in the slot machine condition, there were no significant differences in persistence amongst participants as a function of their gambling classification. Moreover, problem gambling participants in the slot machine condition persisted at the impossible tracing task longer than did problem gambling participants in the control condition. Study 2 (N = 209) systematically replicated Study 1. All participants initially completed two tasks known to deplete self-control strength and a different control condition (math problems) was used. Study 2 results were highly similar to those of Study 1. The results of the studies have implications for the helping professions. Specifically, helping professionals should be aware that problem gamblers might seek out gambling as a means of increasing self-control strength.