To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
When a container with two distinct fluids is subjected to vibrations in microgravity, the interface may undergo a variety of instabilities and develop towards a complex structure, as seen in recent parabolic flight experiments using both miscible and immiscible liquids. Among other things, the selected pattern depends on the frequency and amplitude of the forcing and, crucially, on its orientation with respect to the initial interface. In a parabolic flight experiment, this initial orientation is largely determined by the stage of the parabolic manoeuvre when the forcing is started and the residual gravity level during the period of microgravity. It plays a key role in the appearance of defects and irregularities during the evolution of the interface triggered by the frozen wave instability. Using numerical simulations, we systematically investigate the effect of initial interface orientation on pattern selection in microgravity for both miscible and immiscible fluids, and compare to available experiments. When the interface and the forcing are nearly aligned, the frozen wave instability is dominant, leading to the development of approximately regular columnar patterns. As the initial angle becomes more oblique, the frozen wave growth becomes more irregular and asymmetric and may involve thin auxiliary columns. Sufficiently large angles suppress the frozen wave instability and, depending on the container aspect ratio, may result in a simple two-column final state.
To describe relationships among baseline characteristics, engagement indicators and outcomes for rural participants enrolled in SIPsmartER, a behavioural intervention targeting sugar-sweetened beverage (SSB) intake.
A secondary data analysis. Bivariate analyses determined relationships among baseline characteristics (e.g. age, gender, race, education, income), engagement indicators (completion of 6-month health screening, class attendance, call completion) and SSB outcomes (SSB ounce reduction (i.e. US fluid ounces; 1 US fl. oz = 29·57 ml), reduced ≥12 ounces, achieved ≤8 ounce intake). Generalized linear models tested for significant effects of baseline characteristics on engagement indicators and of baseline characteristics and engagement indicators on SSB outcomes.
South-west Virginia, USA, a rural, medically underserved region.
Participants’ (n 155) mean age was 41 years; most were female (81 %), White (91 %) and earned ≤$US 20 000 per annum (61 %).
All final models were significant. Engagement models predicted 12–17 % of variance, with age being a significant predictor in all three models. SSB outcome models explained 5–70 % of variance. Number of classes attended was a significant predictor of SSB ounce reduction (β = −6·12, P < 0·01). Baseline SSB intake significantly predicted SSB ounce reduction (β = −0·90, P < 0·001) and achieved ≤8 ounce intake (β = 0·98, P < 0·05).
The study identifies several participant baseline characteristics that may impact engagement in and outcomes from a community-based intervention targeting SSB intake. Findings suggest greater attendance of SIPsmartER classes is associated with greater reduction in overall SSB intake; yet engagement variables did not predict other outcomes. Findings will inform the future implementation of SIPsmartER and research studies of similar design and intent.
Americans are not invulnerable to factual information. They do not 'backfire'; facts do not make them less accurate. Instead, they become more accurate, even when corrections target co-partisans. Corrections of fake news yield similar results. Among Republicans, Trump's misstatements are less susceptible to corrections than identical misstatements attributed to other Republicans. While we do not observe facts affecting attitudes, multiple instances of misinformation can increase approval of the responsible politician - but corrections can reduce approval by similar amounts. While corrections do not eliminate false beliefs, they reduce the share of inaccurate beliefs among subjects in this study nearly in half.
Subcutaneous adipose tissue (scAT) and peripheral blood mononuclear cells (PBMC) play a significant role in obesity-associated systemic low-grade inflammation. High-fat diet (HFD) is known to induce inflammatory changes in both scAT and PBMC. However, the time course of the effect of HFD on these systems is still unknown. The aim of the present study was to determine the time course of the effect of HFD on PBMC and scAT. New Zealand white rabbits were fed HFD for 5 or 10 weeks (i.e. HFD-5 and HFD-10) or regular chow (i.e. control (CNT)-5 and CNT-10). Thereafter, metabolic and inflammatory parameters of PBMC and scAT were quantified. HFD induced hyperfattyacidaemia in HFD-5 and HFD-10 groups, with the development of insulin resistance in HFD-10, while no changes were observed in scAT lipid metabolism and inflammatory status. HFD activated the inflammatory pathways in PBMC of HFD-5 group and induced modified autophagy in that of HFD-10. The rate of fat oxidation in PBMC was directly associated with the expression of inflammatory markers and tended to inversely associate with autophagosome formation markers in PBMC. HFD affected systemic substrate metabolism, and the metabolic, inflammatory and autophagy pathways in PBMC in the absence of metabolic and inflammatory changes in scAT. Dietary approaches or interventions to avert HFD-induced changes in PBMC could be essential to prevent metabolic and inflammatory complications of obesity and promote healthier living.
The purpose of this study was to examine whether vehicle type based on size (car vs. other = truck/van/SUV) had an impact on the speeding, acceleration, and braking patterns of older male and female drivers (70 years and older) from a Canadian longitudinal study. The primary hypothesis was that older adults driving larger vehicles (e.g., trucks, SUVs, or vans) would be more likely to speed than those driving cars. Participants (n = 493) had a device installed in their vehicles that recorded their everyday driving. The findings suggest that the type of vehicle driven had little or no impact on per cent of time speeding or on the braking and accelerating patterns of older drivers. Given that the propensity for exceeding the speed limit was high among these older drivers, regardless of vehicle type, future research should examine what effect this behaviour has on older-driver road safety.
We consider the response to periodic forcing between 5 Hz and 50 Hz of an interface separating immiscible fluids under the microgravity conditions of a parabolic flight. Two pairs of liquids with viscosity ratios differing by one order of magnitude are investigated. By combining experimental data with numerical simulations, we describe a variety of dynamics including harmonic and subharmonic (Faraday) waves, frozen waves and drop ejection, determining their thresholds and scaling properties when possible. Interaction between these various modes is facilitated in microgravity by the relative ease with which the interface can move, altering its orientation with respect to the forcing axis. The effects of key factors controlling pattern selection are analysed, including vibrational forcing, viscosity ratio, finite-size effects and residual gravity. Complex behaviour often arises with features on several spatial scales, such as Faraday waves excited on the interface of a larger columnar structure that develops due to the frozen wave instability – this type of state was previously seen in miscible fluid experiments but is described for the first time here in the immiscible case.
Residential instability, including transience (i.e. unusually frequent mobility), is associated with higher risk for emotional and behavioural problems in children and young adults. However, most studies have not compared the effect of recent v. more distal moves on mental health or on mental health treatment. This study examined associations between recent (past year) and distal (past 2–4 years) residential transience and past year major depressive episode (MDE) and mental health treatment in a nationally representative sample of US adolescents aged 12–17.
Data are from the 2010–2014 National Surveys on Drug Use and Health (n = ~107 300 adolescents). T-tests were used to examine the prevalence of MDE by number of moves in the past 5 years among a nationally representative sample of adolescents. Additionally, multivariable logistic regression models were used to evaluate the adjusted association between recent (⩾2 moves in the past year) and distal (⩾4 moves in the past 5 years, but no recent transience) and (1) past year MDE and (2) past year mental health treatment among adolescents with MDE.
MDE prevalence increased linearly with number of moves in the past 5 years (p < 0.001). The adjusted odds of MDE were greater among youths with distal transience (adjusted odds ratio (AOR) = 1.25, 95% confidence interval (CI) = 1.09–1.44) and among those with proximal transience (AOR = 1.31, 95% CI = 1.17–1.46), compared with those without transience in the past 5 years. The MDE prevalence did not differ between those with distal and proximal transience (p = 0.163). In youths with past year MDE, the prevalence of past year mental health treatment was greater among those with proximal transience compared with those without transience (AOR = 1.40, 95% CI = 1.15–1.70), but there was no significant difference in treatment among those with distal v. no transience.
Distal and recent transience are associated with past year MDE among adolescents. Adolescents with MDE who had recent transience were more likely to receive past year mental health treatment compared with those without transience. However, those with only distal transience were not more likely to receive treatment. Parents, school officials and health care providers should be aware that residential mobility in the past 5 years may indicate increased odds of depression among adolescents even among adolescents whose housing stability has improved in the past year.
To evaluate the secondary impact of a multilevel, child-focused, obesity intervention on food-related behaviours (acquisition, preparation, fruit and vegetable (FV) consumption) on youths’ primary caregivers.
B’More Healthy Communities for Kids (BHCK) group-randomized controlled trial promoted access to healthy foods and food-related behaviours through wholesaler and small store strategies, peer mentor-led nutrition education aimed at youths, and social media and text messaging targeting their adult caregivers. Measures included caregivers’ (n 516) self-reported household food acquisition frequency for FV, snacks and grocery items over 30 d, and usual FV consumption in a sub-sample of 226 caregivers via the NCI FV Screener. Hierarchical models assessed average treatment effects (ATE). Treatment-on-the-treated-effect (TTE) analyses evaluated correlation between behavioural change and exposure to BHCK. Exposure scores at post-assessment were based on self-reported viewing of BHCK materials and participating in activities.
Thirty Baltimore City low-income neighbourhoods, USA.
Adult caregivers of youths aged 9–15 years.
Of caregivers, 90·89 % were female; mean age 39·31 (sd 9·31) years. Baseline mean (sd) intake (servings/d) was 1·30 (1·69) fruits and 1·35 (1·05) vegetables. In ATE, no significant intervention effect was found on caregivers’ food-related behaviours. In TTE, each point increase in BHCK exposure score (range: 0–6·9) increased caregivers’ daily fruit consumption by 0·2 servings (0·24 (se 0·11); 95 % CI 0·04, 0·47). Caregivers reporting greater social media exposure tripled their daily fruit intake (3·16 (se 0·92); 95 % CI 1·33, 4·99) and increased their frequency of unhealthy food purchasing v. baseline.
Child-focused community-based nutrition interventions may also benefit family members’ fruit intake. Child-focused interventions should involve adult caregivers and intervention effects on family members should be assessed. Future multilevel studies should consider using social media to improve reach and engage caregiver participants.
The term ‘mood stabiliser’ is ill-defined and lacks clinical utility. We propose a framework to evaluate medications and effectively communicate their mood stabilising properties – their acute and prophylactic efficacy across the domains of mania and depression. The standardised framework provides a common definition to facilitate research and clinical practice.
Declaration of interest
The Treatment Algorithm Group (TAG) was supported logistically by Servier who provided financial assistance with travel and accommodation for those TAG members travelling interstate or overseas to attend the meeting in Sydney (held on 18 November 2017). None of the committee were paid to participate in this project and Servier have not had any input into the content, format or outputs from this project.
The extensive heterogeneity both between and within the medulloblastoma (MB) subgroups underscores a critical need for variant-specific biomarkers and therapeutic strategies. We previously identified a role for the CD271/p75 neurotrophin receptor (p75NTR) in regulating stem/progenitor cells in the SHH MB subgroup. Here, we demonstrate the utility of CD271 as a novel diagnostic and prognostic marker for SHH MB using immunohistochemical analysis as well as transcriptome data across 763 primary tumors. Characterization of CD271+ and CD271- cells by RNA sequencing revealed that these two subpopulations are molecularly distinct, co-existing cellular subsets both in vitro and in vivo. MAPK/ERK signaling is upregulated in the CD271+ population and inhibiting this pathway reduced CD271 levels, stem/progenitor cell proliferation and cell survival as well as cell migration in vitro. Importantly, the MEK inhibitor selumetinib extends survival and reduces CD271 levels in vivo. Our study demonstrates the clinical utility of CD271 as both a diagnostic and prognostic tool for SHH MB tumors and reveals a novel role for MEK inhibitors in targeting CD271+ SHH MB cells.
Introduction: Patients with chronic diseases are known to benefit from exercise. Such patients often visit the emergency department (ED). There are few studies examining prescribing exercise in the ED. We wished to study if exercise prescription in the ED is feasible and effective. Methods: In this pilot prospective block randomized trial, patients in the control group received routine care, whereas the intervention group received a combined written and verbal prescription for moderate exercise (150 minutes/week). Both groups were followed up by phone at 2 months. The primary outcome was achieving 150 min of exercise per week. Secondary outcomes included change in exercise, and differences in reported median weekly exercise. Comparisons were made by Mann-Whitney and Fishers tests (GraphPad). Results: Follow-up was completed for 22 patients (11 Control; 11 Intervention). Baseline reported median (with IQR) weekly exercise was similar between groups; Control 0(0-0)min; Intervention 0(0-45)min. There was no difference between groups for the primary outcome of 150 min/week at 2 months (Control 3/11; Intervention 4/11, RR 1.33 (95%CI 0.38-4.6;p=1.0). There was a significant increase in median exercise from baseline in both groups, but no difference between the groups (Control 75(10-225)min; Intervention 120(52.5-150)min;NS). 3 control patients actually received exercise prescription as part of routine care. A post-hoc comparison of patients receiving intervention vs. no intervention, revealed an increase in patients meeting the primary target of 150min/week (No intervention 0/8; Intervention 7/14, RR 2.0 (95%CI 1.2-3.4);p=0.023). Conclusion: Recruitment was feasible, however our study was underpowered to quantify an estimated effect size. As a significant proportion of the control group received the intervention (as part of standard care), any potential measurable effect was diluted. The improvement seen in patients receiving intervention and the increase in reported exercise in both groups (possible Hawthorne effect) suggests that exercise prescription for ED patients may be beneficial.
Following the 2016 U.S. election, researchers and policymakers have become intensely concerned about the dissemination of “fake news,” or false news stories in circulation (Lazer et al., 2017). Research indicates that fake news is shared widely and has a pro-Republican tilt (Allcott and Gentzkow, 2017). Facebook now flags dubious stories as disputed and tries to block fake news publishers (Mosseri, 2016). While the typical misstatements of politicians can be corrected (Nyhan et al., 2017), the sheer depth of fake news’s conspiracizing may preclude correction. Can fake news be corrected?
The morphology of englacial drainage networks and their temporal evolution are poorly characterised, particularly within cold ice masses. At present, direct observations of englacial channels are restricted in both spatial and temporal resolution. Through novel use of a terrestrial laser scanning (TLS) system, the interior geometry of an englacial channel in Austre Brøggerbreen, Svalbard, was reconstructed and mapped. Twenty-eight laser scan surveys were conducted in March 2016, capturing the glacier surface around a moulin entrance and the uppermost 122 m reach of the adjoining conduit. The resulting point clouds provide detailed 3-D visualisation of the channel with point accuracy of 6.54 mm, despite low (<60%) overall laser returns as a result of the physical and optical properties of the clean ice, snow, hoar frost and sediment surfaces forming the conduit interior. These point clouds are used to map the conduit morphology, enabling extraction of millimetre-to-centimetre scale geometric measurements. The conduit meanders at a depth of 48 m, with a sinuosity of 2.7, exhibiting teardrop shaped cross-section morphology. This improvement upon traditional surveying techniques demonstrates the potential of TLS as an investigative tool to elucidate the nature of glacier hydrological networks, through reconstruction of channel geometry and wall composition.
Combinatorial auctions enhance our ability to efficiently allocate multiple resources in complex economic environments. They explicitly allow buyers and sellers of goods and services to bid on packages of items with related values or costs. For example, “I bid $10 to buy 1 unit of item A and 2 units of item B, but I won't pay anything unless I get everything.” They also allow buyers, sellers and the auctioneer to impose logical constraints that limit the feasible set of auction allocations. For example, “I bid $12 to buy 2 units of item C OR $15 to buy 3 units of item D, but I don't want both.” Finally, they can handle functional relationships amongst bids or allocations, such as budget constraints or aggregation limits that allow many bids to be connected together. For example, “I won't spend more than a total of $35 on all my bids” or “This auction will allocate no more than a total of 7 units of items F, G and H.”
There are several reasons to prefer to have the bidding message space expanded beyond the simple space used for traditional single commodity auctions. As Bykowsky et al. (2000) point out, when values have strong complementarities, there is a danger of ‘financial exposure’ that results in losses to bidders if combinatorial bidding is not allowed. For example, in the case of complementary items such as airport take-off and landing times, the ability to reduce uncertainty to the bidder by allowing him to precisely declare his object of value, a cycle of slots for an entire daily flight pattern, is obvious: one component slot not acquired ruins the value of the flight cycle. In the same situation substitution possibilities would also be important to consider: if flight cycle A is not won, cycle B may be an appropriate though less valuable substitute for the crew and equipment available. Allocation inefficiencies due to financial exposure in noncombinatorial auctions have been frequently demonstrated in experiments beginning with Rassenti et al. (1982) (see also Porter (1999), Banks et al. (1989), Ledyard et al. (2002) and Kwasnika et al. (1998)).
Background: Dysphagia is a common and devastating complication after acute stroke. Percutaneous endoscopic gastrostomy (PEG) tubes are often placed for persistent dysphagia. However, little is known regarding outcomes after PEG tube placement. Methods: We used a 10-year Ontario Stroke Registry to shed light on the clinical outcomes of patients with PEG tube insertion after ischemic stroke or intracranial hemorrhage compared to patients with only NG tubes, including rate of pneumonia, disability, and mortality. Results: Using propensity score matching, 1,793 patients were successfully matched and had similar baseline characteristics. Compared with NG, patients with PEG had a higher rate of pneumonia (32.6% vs. 20.6%; RR 1.59), higher disability at discharge (modified Rankin Scale Score 3-5; 74.0% vs. 65.4%; RR 1.13), and higher rate of long-term care placement (27.1% vs. 9.3%; RR 2.9). >From stroke onset, there was a lower rate of death in patients with PEG compared to NG at 30 days (15.3% vs. 34.3%; RR 0.45) but no difference at 2 years (52.8% vs. 53.5%; RR 0.99, p=0.71). *All significant p <0.0001. Conclusions: In conclusion, PEG tube placement after stroke may prolong survival in patients with poor outcomes. Our study provides a framework for discussions between physicians, patients, and families with regards to expected prognosis after PEG tube placement.
Background: In patients with acute stroke, nasogastric (NG) tubes are commonly inserted for feeding when dysphagia is identified, and percutaneous endoscopic gastrostomy (PEG) tubes are placed for severe or persistent dysphagia. However, little is known regarding predictors of PEG insertion. Methods: We used the Ontario stroke registry from 2003-2013 to identify baseline characteristics of all patients with NG or PEG tube insertion after stroke. We used multiple logistic regression with backwards selection to determine variables that were independent predictors of PEG tube insertion during admission. Results: 4002 patients with NG and 1903 patients with PEG were included in the analysis. Independent predictors of PEG were: Age (80+ vs. <60; odds ratio [OR] 1.70), past history of stroke (OR 1.17), higher stroke severity (severe vs. mild stroke; OR 1.37), stroke unit admission (OR 1.46), and dysphagia screening (OR 1.52). Factors associated with reduced odds of PEG insertion were: Prior history of peptic ulcer disease (OR 0.70), prior independence (OR 0.78), dementia (OR 0.76), palliative status (OR 0.49), and thrombolysis (OR 0.66). *All p<0.01 Conclusions: The strongest predictors of PEG were older age, higher stroke severity, stroke unit admission and dysphagia screening. Patients with dementia had reduced odds of PEG. Thrombolysis also reduced odds of PEG and may be protective.