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Aircraft measurements reveal ice supersaturation statistics in cirrus (ISSs) with broad maxima around ice saturation and pronounced variance. In this study, processes shaping ISSs in midlatitude and tropical upper tropospheric conditions are systematically investigated. Water vapor deposition and sublimation of size‐resolved ice crystal populations are simulated in an air parcel framework. Mesoscale temperature fluctuations (MTFs) due to gravity waves force the temporal evolution of supersaturation. Various levels of background wave forcing and cirrus thickness are distinguished in stochastic ensemble simulations. Kinetic limitations to ice mass growth are brought about by supersaturation‐dependent deposition coefficients that represent efficient and inefficient growth modes as a function of ice crystal size. The simulations identify a wide range of deposition coefficients in cirrus, but most values stay above 0.01 such that kinetic limitations to water uptake remain moderate. Supersaturation quenching times are long, typically 0.5–2 hr. The wave forcing thus causes a remarkably large variability in ISSs and cirrus microphysical properties except in the thickest cirrus, producing ensemble‐mean ISSs in line with in‐situ measurements. ISS variance is controlled by MTFs and increases with decreasing cirrus integral radii. In comparison, the impact of ice crystal growth rates on ISSs is small. These results contribute to efforts directed at identifying and solving issues associated with ice‐supersaturated areas and non‐equilibrium cirrus physics in global models. Plain Language Summary: Measurements show that cold, high cirrus clouds evolve in ice‐supersaturated states away from equilibrium, which sets them apart from low‐level liquid water clouds. Such cloud states are brought about by rapidly displacing cloudy air parcels in the vertical wind field. The resulting temperature changes cause ice crystals to either grow or shrink in size by uptake or release of water molecules, which, in turn, tends to restore equilibrium. We carefully examine how ice supersaturation and cirrus properties respond to changes in vertical wind speeds for various ice growth models. We show that cloud‐scale wave motions determine to a large extent the frequency of occurrence of ice‐supersaturated states. The sensitivity to cloud ice growth is much weaker. Our results help interpret atmospheric observations and may improve the representation of cirrus in global models. Key Points: This study presents a process‐based, systematic investigation of key factors controlling ice supersaturation statistics within cirrusGravity wave‐induced mesoscale temperature fluctuations cause a remarkably large variability in ice supersaturationIce supersaturation statistics are not strongly modified by depositional growth with supersaturation‐dependent deposition coefficients [ABSTRACT FROM AUTHOR]

Cirrus ice crystals are produced heterogeneously on ice‐nucleating particles (INPs) and homogeneously in supercooled liquid solution droplets. They grow by uptake of water molecules from the ice‐supersaturated vapor. The precursor particles, characterized by disparate ice nucleation abilities and number concentrations, compete for available vapor during ice formation events. We investigate cirrus formation events systematically in different temperature and updraft regimes, and for different INP number concentrations and time‐independent nucleation efficiencies. We consider vertical air motion variability due to mesoscale gravity waves and effects of supersaturation‐dependent deposition coefficients for water molecules on ice surfaces. We analyze ice crystal properties to better understand the dynamics of competing nucleation processes. We study the reduction of ice crystal numbers produced by homogeneous freezing due to INPs in both, individual simulations assuming constant updraft speeds and in ensemble simulations based on a stochastic representation of vertical wind speed fluctuations. We simulate and interpret probability distributions of total nucleated ice crystal number concentrations, showing signatures of homogeneous and heterogeneous nucleation. At typically observed, mean updraft speeds (≈15 cm s−1) competing nucleation should occur frequently, even at rather low INP number concentrations (<10 L−1). INPs increase cirrus occurrence and may alter cirrus microphysical properties without entirely suppressing homogeneous freezing events. We suggest to improve ice growth models, especially for low cirrus temperatures (<220 K) and low ice supersaturation (<0.3). Plain Language Summary: Despite decades of research the role of ice‐nucleating particles (INPs) in cirrus formation remains poorly quantified. Our study synthesizes and re‐interprets current knowledge on cirrus formation pathways. We study the competition between liquid particles and INPs in cirrus formation and suggest that competing ice nucleation tends to be more the rule than an exception, except in very clean atmospheric conditions. Despite their low number concentrations, INPs exert a disproportionate influence on microphysical properties of cirrus in the formation stage, for which we provide quantitative evidence. Our work confirms that cirrus formation and vertical air motion variability cannot be considered separately from each other. Deposition of water vapor on ice crystal surfaces constitutes the major growth process for small ice crystals following nucleation. We critically discuss molecular‐level processes controlling cloud ice growth and suggest that current model representation is incomplete, especially in the case of very cold cirrus. Our results and insights aim at improving cirrus parameterization schemes employed in global models and guiding in situ observations and laboratory measurements. Key Points: Competing ice nucleation involving liquid solution droplets and INPs occurs frequently in cirrus formationEven poor INPs influence cirrus formation for moderately high mean updraft speeds and low number concentrationsGrowth of ice crystals by water vapor deposition in low‐temperature cirrus clouds needs further study [ABSTRACT FROM AUTHOR]

Scientific and clinical evidence on the health effects of probiotics has expanded rapidly in recent years and points towards benefits for a number of specific health conditions, particularly those related to the gut. Healthcare professionals are important conduits in the transfer of evidence‐based messages on probiotics, but research indicates many do not consider themselves to have good knowledge in this area. To identify potential solutions to support healthcare professionals, the British Nutrition Foundation held a one‐day roundtable event on 7 February 2019 to gather expert views on the content of, and best delivery mode for, evidence‐based resources to guide healthcare professional advice about the use of probiotics. This report describes the main themes emerging from the discussions and the group's recommendation for the development of a UK‐focused online toolkit for healthcare professionals, which assimilates, appraises and translates current scientific knowledge of probiotics to promote evidence‐based practice for the benefit of patients. [ABSTRACT FROM AUTHOR]

Compacted bentonite is proposed as an engineered barrier material within facilities for the geological disposal of radioactive waste. Barrier performance and its interaction with a free gas phase must be considered as part of sound repository design. This study involved the long-term experimental examination of gas flow in precompacted bentonite, with particular consideration of gas network stability. Results demonstrate that the stress field experienced by the clay is strongly coupled with gas flow. For the first time, three controls on this behaviour are considered: (i) injection flow rate, (ii) constant vs. variable gas pressure, and (iii) stimulation of the microfracture network. A detailed stress analysis is used to examine changes in the gas flow network. The results indicate a degree of metastability despite these changes, except in the case of stimulation of the microfracture network by removal of the primary drainage route. In this case, a rapid redevelopment of the gas flow network was observed. As such, availability of drainage pathways will represent a key control on the generation of peak gas pressures and distribution of gas within the engineered barrier. The cessation of gas flow is shown to result in crack closure and self-sealing. Observations from this study highlight that characterisation of the gas network distribution is of fundamental importance in predicting gas dissipation rates and understanding the long-term fate of gas in radioactive waste repositories. [ABSTRACT FROM AUTHOR]

Summary: Consumption of larger portion sizes is associated with higher energy intake and weight status in children. As parents play a pivotal role in child feeding, we synthesized literature on 'parental portioning practices' using a mixed methods systematic design to inform future strategies addressing portion sizes served to children. Electronic databases PubMed, EMBASE, SCOPUS, PsycINFO and CINAHL Plus were searched. Two reviewers independently screened 385 abstracts and assessed 71 full‐text articles against eligibility criteria: studies assessing portioning of foods or beverages by parent(s) with ≥1 child aged 2–12 years. Narrative synthesis of 14 quantitative studies found that portion sizes parents serve vary substantially and are influenced by amounts parents serve themselves, perceived child hunger and parent and child body size. Thematic synthesis of 14 qualitative studies found that parents serve the portion sizes they learn to be appropriate for their child to be fed. Portioning is influenced by parents' desires for a healthy child with a balanced diet. Future guidance on appropriate portion sizes for children would ideally present recommended portion sizes for first serving, incremental with age. Future research is however needed to assess the adoption and efficacy of providing such guidance to families. [ABSTRACT FROM AUTHOR]

The determination of effective diffusion coefficients of gases or solutes in the water‐saturated pore space of mudrocks is time consuming and technically challenging. Yet reliable values of effective diffusion coefficients are important to predict migration of hydrocarbon gases in unconventional reservoirs, dissipation of (explosive) gases through clay barriers in radioactive waste repositories, mineral alteration of seals to geological CO2 storage reservoirs, and contaminant migration through acquitards. In this study, small‐angle and very small angle neutron scattering techniques have been utilized to determine a range of transport properties in mudrocks, including porosity, pore size distributions, and surface and volume fractal dimensions of pores and grains, from which diffusive transport parameters can be estimated. Using a fractal model derived from Archie's law, we calculate effective diffusion coefficients from these parameters and compare them to laboratory‐derived effective diffusion coefficients for CO2, H2, CH4, and HTO on either the same or related mudrock samples. The samples include Opalinus Shale from the underground laboratory in Mont Terri, Switzerland, Boom Clay from a core drilled in Mol, Belgium, and a marine claystone cored in Utah, USA. The predicted values were compared to laboratory diffusion measurements. The measured and modeled diffusion coefficients show good agreement, differing generally by less than factor 5. Neutron or X‐ray scattering analysis is therefore proposed as a novel method for fast, accurate estimation of effective diffusion coefficients in mudrocks, together with simultaneous measurement of multiple transport parameters including porosity, pore size distributions, and surface areas, important for (reactive) transport modeling. Key Points: Effective diffusion coefficients are important to assess mineral reaction rates or transport in low‐permeability rocksEffective diffusion coefficients can be predicted using fractal dimensionsFractal dimensions can be obtained using small‐angle neutron scattering data [ABSTRACT FROM AUTHOR]

Objective: To assess the feasibility and efficacy of implementing a treat-to-target approach versus usual care in a US-based cohort of rheumatoid arthritis patients.Methods: In this behavioral intervention trial, rheumatology practices were cluster-randomized to provide treat-to-target care or usual care. Eligible patients with moderate/high disease activity (Clinical Disease Activity Index [CDAI] score >10) were followed for 12 months. Both treat-to-target and usual care patients were seen every 3 months. Treat-to-target providers were to have monthly visits with treatment acceleration at a minimum of every 3 months in patients with CDAI score >10; additional visits and treatment acceleration were at the discretion of usual care providers and patients. Coprimary end points were feasibility, assessed by rate of treatment acceleration conditional on CDAI score >10, and achievement of low disease activity (LDA; CDAI score ≤10) by an intent-to-treat analysis.Results: A total of 14 practice sites per study arm were included (246 patients receiving treat-to-target and 286 receiving usual care). The groups had similar baseline demographic and clinical characteristics. Rates of treatment acceleration (treat-to-target 47% versus usual care 50%; odds ratio [OR] 0.92 [95% confidence interval (95% CI) 0.64, 1.34]) and achievement of LDA (treat-to-target 57% versus usual care 55%; OR 1.05 [95% CI 0.60, 1.84]) were similar between groups. Treat-to-target providers reported patient reluctance and medication lag time as common barriers to treatment acceleration.Conclusion: This study is the first to examine the feasibility and efficacy of a treat-to-target approach in typical US rheumatology practice. Treat-to-target care was not associated with increased likelihood of treatment acceleration or achievement of LDA, and barriers to treatment acceleration were identified. [ABSTRACT FROM AUTHOR]

The success of childhood weight management programmes relies on family engagement. While attendance offers many benefits including the support to make positive lifestyle changes, the majority of families referred to treatment decline. Moreover, for those who do attend, benefits are often compromised by high programme attrition. This systematic review investigated factors influencing attendance at community-based lifestyle programmes among families of overweight or obese children. A narrative synthesis approach was used to allow for the inclusion of quantitative, qualitative and mixed-method study designs. Thirteen studies met the inclusion criteria. Results suggest that parents provided the impetus for programme initiation, and this was driven largely by a concern for their child's psychological health and wellbeing. More often than not, children went along without any real reason or interest in attending. Over the course of the programme, however, children's positive social experiences such as having fun and making friends fostered the desire to continue. The stigma surrounding excess weight and the denial of the issue amongst some parents presented barriers to enrolment and warrant further study. This study provides practical recommendations to guide future policy makers, programme delivery teams and researchers in developing strategies to boost recruitment and minimise attrition. [ABSTRACT FROM AUTHOR]

The flow of water along discontinuities, such as fractures or faults, is of paramount importance in understanding the hydrogeology of many geological settings. An experimental study was undertaken comprising two experiments on a 30° slip-plane filled with kaolinite or Ball Clay gouge using a bespoke Angled Shear Rig ( ASR). The gouge was initially loaded in equal step changes in vertical stress, followed by unloading of the sample in similar equal steps. This was followed by reloading to a new maximum stress, followed by unloading; the test history was therefore load-unload-reload-unload ( LURU). The transmissivity of the kaolinite and Ball Clay gouge showed a power-law relationship with vertical stress. The LURU history showed considerable hysteresis, with flow effectively unchanged during unloading, even when vertical stress was close to zero. Reloading resulted in flow similar to that seen during unloading suggesting that the unloading-reloading path is similar to the rebound-reconsolidation line in classic soil mechanics. These observations show the importance of stress history on fracture flow; consideration of just the current stress acting upon a fracture may result in inaccuracies of predicted hydraulic flow. Once a new stress maximum was achieved the transmissivity of the fracture continued to reduce. No significant variation was seen in the flow response of kaolinite and Ball Clay gouge suggesting that the inclusion of illite and quartz did not have a significant influence on the form of the relationship between stress and flow, i.e. both described by a power-law. [ABSTRACT FROM AUTHOR]

Objective Growth hormone deficiency is a common feature of Prader-Willi syndrome; however, biochemical deficiency is not uniformly demonstrated. Criteria for GH treatment in paediatric PWS vary with some countries requiring documentation of biochemical GH deficiency. Data regarding the significance of age in the interpretation of GH stimulation test results, particularly in infants, are lacking. We aimed to assess age-related trends in the prevalence of biochemical GH deficiency in infants and children with PWS. Design A retrospective chart review was conducted. Data from children with Prader-Willi syndrome that had GH stimulation tests performed at the Hospital for Sick Children in Toronto between the years 2000 and 2012 were collected. Patient Charts of 47 children 0·4-15·5 years of age with PWS that had GH stimulation tests were reviewed. Measurements Biochemical GH status in relation to age and body mass index. Results Thirty-two of 47 patients (68%) were biochemically GH deficient. GH deficiency was significantly associated with older age ( r = 0·45, P = 0·02) and higher body-mass-index z-score ( r = 0·45, P = 0·02). Biochemical GH deficiency was less prevalent up to 18 months of age (3/11 27%) compared with older children (29/36 [81%]; P = 0·001). A higher prevalence of GH deficiency was also detected in obese patients (14/16 [88%]) compared with nonobese patients (18/31 [58%]; P = 0·04). Conclusions The utility of performing GH stimulation tests as an indication of GH status under 18 months of age in Prader-Willi syndrome is questionable. If performed, results should be carefully interpreted in the context of age. [ABSTRACT FROM AUTHOR]

Most previous research on indoor environments and health has studied school children or occupants in non-school settings. This investigation assessed building-related health symptoms and classroom characteristics via telephone survey of New York State school teachers. Participants were asked about 14 building-related symptoms and 23 classroom characteristics potentially related to poor indoor air quality ( IAQ). Poisson regression analysis was used to assess the relationship between these symptoms and each classroom characteristic, controlling for potential confounders. About 500 teachers completed the survey. The most frequently reported classroom characteristics included open shelving (70.7%), food eaten in class (65.5%), dust (59.1%), and carpeting (46.9%). The most commonly reported symptoms included sinus problems (16.8%), headache (15.0%), allergies/congestion (14.8%), and throat irritation (14.6%). Experiencing one or more symptoms was associated most strongly with reported dust (relative risk ( RR) = 3.67; 95% confidence interval ( CI): 2.62-5.13), dust reservoirs ( RR = 2.13; 95% CI: 1.72-2.65), paint odors ( RR = 1.73; 95% CI: 1.40-2.13), mold ( RR = 1.71; 95% CI: 1.39-2.11), and moldy odors ( RR = 1.65 95% CI: 1.30-2.10). Stronger associations were found with increasing numbers of reported IAQ-related classroom characteristics. Similar results were found with having any building-related allergic/respiratory symptom. This research adds to the body of evidence underscoring the importance to occupant health of school IAQ. [ABSTRACT FROM AUTHOR]

Objectives Pre-diabetes is an important indicator of future diabetes burden and many countries are reporting prevalence estimates of pre-diabetes. To date in Ireland, estimates of the prevalence of pre-diabetes were unavailable. Our objectives were to estimate the prevalence of pre-diabetes in a nationally representative sample of Irish adults and to explore determinants of pre-diabetes. Methods The Survey of Lifestyle Attitudes and Nutrition 2007 was a cross-sectional survey on health and lifestyle in a nationally representative sample of Irish adults. Analysis was performed on a subsample of 1132 participants ≥ 45 years who provided blood samples. Determination of pre-diabetes was based on American Diabetes Association HbA1c cut points of 39-46 mmol/mol (5.7-6.4%). To explore determinants, we modelled pre-diabetes prevalence as a function of a set of health system and socio-demographic variables using logistic regression. Results The overall weighted prevalence estimate of pre-diabetes in participants ≥ 45 years was 19.8% (95% CI 16.4-23.9). There was no significant difference between age or gender-specific prevalence rates. Obesity was significantly associated with pre-diabetes on univariate and multivariate analysis. Population attributable fraction estimates for excess BMI, physical inactivity and poor diet as causes of pre-diabetes were 31.3% (95% CI -3.9 to 54.5), 10.0% (95% CI -2.7 to 21.3) and 6.1% (95% CI -4.9 to 15.9), respectively. Conclusions The high levels of pre-diabetes detected in this study are worrying. Population level interventions to address diet and lifestyle factors are needed urgently to prevent progression to diabetes in high-risk individuals. [ABSTRACT FROM AUTHOR]

Objective To examine prescribing practices in the use of biologic and nonbiologic disease-modifying antirheumatic drugs (DMARDs) to treat patients with rheumatoid arthritis (RA), before and after publication of the American College of Rheumatology (ACR) treatment recommendations. Methods Biologics-naive RA patients under the care of a rheumatologist in the US were identified from the Consortium of Rheumatology Researchers of North America registry. Patients were included if their visits occurred prior to and/or at least 6 months after publication of the ACR treatment recommendations (time periods of February 2002-June 2008 versus December 2008-December 2009). The population was divided into 2 mutually exclusive cohorts: 1) methotrexate (MTX) monotherapy users, and 2) multiple nonbiologic DMARD users. Initiation or dose escalation of biologic and nonbiologic DMARDs in response to active disease was assessed cross-sectionally and longitudinally in comparison to the ACR recommendations. The impact of the publication of the ACR recommendations on treatment practices was assessed using logistic regression, stratified by disease activity and adjusted for clustering of physicians and geographic region. Results After 1 visit, 24-37% of patients receiving MTX monotherapy who had moderate disease activity and a poor prognosis or high disease activity received care consistent with the ACR recommendations; after 2 visits, 34-56% of the MTX monotherapy group received care consistent with the recommendations. In the patients receiving multiple nonbiologic DMARDs, 31-47% of those with moderate or high disease activity received care consistent with the recommendations after 1 visit, and 43-51% received such care after 2 visits. Publication of the recommendations did not significantly change treatment patterns for those with active disease. Conclusion Substantial numbers of RA patients with active disease did not receive care consistent with the current ACR treatment recommendations. Innovative approaches to improve care are necessary. [ABSTRACT FROM AUTHOR]

Summary [ABSTRACT FROM AUTHOR]

All biological tissues are three dimensional and contain structures that span a range of length scales from nanometres through to hundreds of millimetres. These are not ideally suited to current three-dimensional characterization techniques such as X-ray or transmission electron tomography. Such detailed morphological analysis is critical to understanding the structural features relevant to tissue function and designing therapeutic strategies intended to address structural deficiencies encountered in pathological states. We show that use of focused ion beam milling combined with scanning electron microscopy can provide three-dimensional information at nanometre resolution from biologically relevant volumes of material, in this case dentine. [ABSTRACT FROM AUTHOR]