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The Coupled Model Intercomparison Project (CMIP) is one of the biggest international efforts aimed at better understanding the past, present, and future of climate changes in a multi-model context. A total of 21 model intercomparison projects (MIPs) were endorsed in its sixth phase (CMIP6), which included 190 different experiments that were used to simulate 40 000 years and produced around 40 PB of data in total. This paper presents the main findings obtained from the CPMIP (the Computational Performance Model Intercomparison Project), a collection of a common set of metrics, specifically designed for assessing climate model performance. These metrics were exclusively collected from the production runs of experiments used in CMIP6 and primarily from institutions within the IS-ENES3 consortium. The document presents the full set of CPMIP metrics per institution and experiment, including a detailed analysis and discussion of each of the measurements. During the analysis, we found a positive correlation between the core hours needed, the complexity of the models, and the resolution used. Likewise, we show that between 5 %–15 % of the execution cost is spent in the coupling between independent components, and it only gets worse by increasing the number of resources. From the data, it is clear that queue times have a great impact on the actual speed achieved and have a huge variability across different institutions, ranging from none to up to 78 % execution overhead. Furthermore, our evaluation shows that the estimated carbon footprint of running such big simulations within the IS-ENES3 consortium is 1692 t of CO2 equivalent. As a result of the collection, we contribute to the creation of a comprehensive database for future community reference, establishing a benchmark for evaluation and facilitating the multi-model, multi-platform comparisons crucial for understanding climate modelling performance. Given the diverse range of applications, configurations, and hardware utilised, further work is required for the standardisation and formulation of general rules. The paper concludes with recommendations for future exercises aimed at addressing the encountered challenges which will facilitate more collections of a similar nature.

Aerosol radiative forcing uncertainty affects estimates of climate sensitivity and limits model skill in terms of making climate projections. Efforts to improve the representations of physical processes in climate models, including extensive comparisons with observations, have not significantly constrained the range of possible aerosol forcing values. A far stronger constraint, in particular for the lower (most-negative) bound, can be achieved using global mean energy balance arguments based on observed changes in historical temperature. Here, we show that structural deficiencies in a climate model, revealed as inconsistencies among observationally constrained cloud properties in the model, limit the effectiveness of observational constraint of the uncertain physical processes. We sample the uncertainty in 37 model parameters related to aerosols, clouds, and radiation in a perturbed parameter ensemble of the UK Earth System Model and evaluate 1 million model variants (different parameter settings from Gaussian process emulators) against satellite-derived observations over several cloudy regions. Our analysis of a very large set of model variants exposes model internal inconsistencies that would not be apparent in a small set of model simulations, of an order that may be evaluated during model-tuning efforts. Incorporating observations associated with these inconsistencies weakens any forcing constraint because they require a wider range of parameter values to accommodate conflicting information. We show that, by neglecting variables associated with these inconsistencies, it is possible to reduce the parametric uncertainty in global mean aerosol forcing by more than 50 %, constraining it to a range (around −1.3 to −0.1 W m−2) in close agreement with energy balance constraints. Our estimated aerosol forcing range is the maximum feasible constraint using our structurally imperfect model and the chosen observations. Structural model developments targeted at the identified inconsistencies would enable a larger set of observations to be used for constraint, which would then very likely narrow the uncertainty further and possibly alter the central estimate. Such an approach provides a rigorous pathway to improved model realism and reduced uncertainty that has so far not been achieved through the normal model development approach.

The Martabe gold deposits in Sumatra formed in a shallow crustal epithermal environment associated with intermediate mafic intrusions adjacent to an active right-lateral wrench system. Gas/fluid temperatures reached 200–350 ∘C. The structural geology suggests episodic switches in stress orientations during a Plio-Pleistocene seismotectonic evolution. Different mineralisation events may have been associated with oscillations in this earthquake cycle, so samples containing alunite were collected for 40Ar / 39Ar geochronology to constrain the timing. 39Ar diffusion experiments were performed to constrain variation in argon retentivity. The age spectra were produced by incremental step-heating with heating times chosen so similar percentages of 39Ar gas release occurred during as many steps as possible. This ensured the detail necessary for analysis of the complex morphology of these spectra by applying the method of asymptotes and limits, which enabled recognition of different growth events of alunite in overprinting fluid systems. It was possible to provide estimates as to the frequency of individual events and their duration. The heating schedule also ensured that Arrhenius data populated the inverse temperature axis with sufficient detail to allow modelling. Activation energies were between 370–660 kJ mol−1. Application of Dodson's recursion determined closure temperatures that range from 400–560 ∘C for a cooling rate of 100 ∘C Ma−1. Such estimates are higher than any temperature to be expected in the natural system, giving confidence that the ages represent the timing of growth during periods of active fluid movement and alteration: a hypothesis confirmed by modelling age spectra using the MacArgon program. We conclude that gold in the Purnama pit resulted from overprinting fluid rock interactions during very short mineralisation episodes at ∼2.25 and ∼2.00 Ma.

In this study, we provide 40Ar / 39Ar geochronology data from a suite of variably deformed rocks from a region of low-grade metamorphism within the Cambro–Ordovician Delamerian Orogen, South Australia. Low-grade metamorphic rocks such as these can contain both detrital minerals and minerals newly grown or partly recrystallised during diagenesis and metamorphism. Hence, they typically yield complex 40Ar / 39Ar age spectra that can be difficult to interpret. Therefore, we have undertaken furnace step heating 40Ar / 39Ar geochronology to obtain age spectra with many steps to allow for application of the method of asymptotes and limits and recognition of the effects of mixing. The samples analysed range from siltstone and shale to phyllite and contain muscovite or phengite with minor microcline as determined by hyperspectral mineralogical characterisation. Whole rock 40Ar / 39Ar analyses were undertaken in most samples due to their very fine-grained nature. All samples are dominated by radiogenic 40Ar, and contain minimal evidence for atmospheric Ca- or Cl-derived argon. Chloritisation may have resulted in limited recoil, causing 39Ar argon loss in some samples, which is especially evident within the first few percent of gas released. Most of the age data, however, appear to have some geological significance. Viewed with respect to the known depositional ages of the stratigraphic units, the age spectra from this study do appear to record both detrital mineral ages and ages related to the varying influence of either cooling or deformation-induced recrystallisation. The shape of the age spectra and the degree of deformation in the phyllites suggest the younger ages may record recrystallisation of detrital minerals and/or new mica growth during deformation. Given that the younger limit of deformation recorded in the high-metamorphic-grade regions of the Delamerian Orogen is ca. 490 Ma, the ca. 470 to ca. 458 Ma ages obtained in this study suggest deformation in low-grade shear zones within the Delamerian Orogen may have persisted until ca. 20–32 million years after high-temperature ductile deformation in the high-grade regions of the orogen. We suggest that these younger ages for deformation could reflect reactivation of older structures formed both during rift basin formation and during the main peak of the Delamerian orogeny itself. The younger ca. 470 to ca. 458 Ma deformation may have been facilitated by far-field tectonic processes occurring along the eastern paleo-Pacific margin of Gondwana.

The Late Cretaceous Asteroussia event as recorded in the Cyclades is a potential key to the tectonic evolution of Western Tethys. Microstructural analysis and 40Ar/39Ar geochronology on garnet–mica schists and the underlying granitoid basement terrane on the island of Ios demonstrates evidence of a Late Cretaceous high-pressure, medium-temperature (HP–MT) metamorphic event. This suggests that the Asteroussia crystalline nappe on Crete extended northward to include these Gondwanan tectonic slices. In this case, the northern part of the Asteroussia nappe (on Ios) is overlain by the terrane stack defined by the individual slices of the Cycladic Eclogite–Blueschist Unit, whereas in the south (in Crete) the Asteroussia slices are near the top of a nappe stack defined by the individual tectonic units of the external Hellenides. This geometry implies that accretion of the Ios basement terrane involved a significant leap of the subduction megathrust (250–300 km) southward. Accretion needs to have commenced at or about ∼38 Ma, when the already partially exhumed slices of the Cycladic Eclogite–Blueschist Unit began to thrust over the Ios basement. By ∼35–34 Ma, the subduction jump had been accomplished, and renewed rollback began the extreme extension that led to the exhumation of the Ios metamorphic core complex.

A climate model represents a multitude of processes on a variety of timescales and space scales: a canonical example of multi-physics multi-scale modeling. The underlying climate system is physically characterized by sensitive dependence on initial conditions, and natural stochastic variability, so very long integrations are needed to extract signals of climate change. Algorithms generally possess weak scaling and can be I/O and/or memory-bound. Such weak-scaling, I/O, and memory-bound multi-physics codes present particular challenges to computational performance. Traditional metrics of computational efficiency such as performance counters and scaling curves do not tell us enough about real sustained performance from climate models on different machines. They also do not provide a satisfactory basis for comparative information across models. codes present particular challenges to computational performance. We introduce a set of metrics that can be used for the study of computational performance of climate (and Earth system) models. These measures do not require specialized software or specific hardware counters, and should be accessible to anyone. They are independent of platform and underlying parallel programming models. We show how these metrics can be used to measure actually attained performance of Earth system models on different machines, and identify the most fruitful areas of research and development for performance engineering. codes present particular challenges to computational performance. We present results for these measures for a diverse suite of models from several modeling centers, and propose to use these measures as a basis for a CPMIP, a computational performance model intercomparison project (MIP).

ENGLISH ABSTRACT: Current industrial engineering paradigms aim to improve quality and profits, and emphasise labour-reduction, specialisation, analysis and optimisation. This can be at odds with the needs in a developing country. We suggest that the emphasis of industrial engineering be re-orientated to support employment growth, the identification of new products and services, education, and training. Pedagogical methods and computer usage should satisfy the needs of such environments. It is not argued that uneconomic and non-competitive processes should be tolerated, rather that activities, which protect and increase employment levels, should be emphasised. Experiences in Kenya and South Africa are used to support this hypothesis.AFRIKAANSE OPSOMMING: Huidige Bedryfsingenieursweseparadigmas beoog om kwaliteit en wins te verbeter en plaas die klem op arbeidsvermindering, spesialisasie, analise en optimisasie. Hierdie tendens is waarskynlik strydig met die behoeftes van ontwikkelende lande. Ons voorstel is dat die fokus van Bedryfsingenieurwese verskuif moet word om indiensnemingsgroei te bewerkstellig, te help met die identifisering van nuwe produkte en dienste, onderwys te bevorder en opleiding te verskaf. Pedagogiese metodes en rekenaargebruik behoort die behoeftes van hierdie omgewings te bevredig. Die argument is nie dat onproduktiewe en nie-mededingende prosesse verduur moet word nie, maar dat die aktiwiteite wat indiensnemingsvlakke verhoog en beskerm, beklemtoon moet word. Eksperimente in Kenia en Suid-Afrika sal gebruik word om hierdie hipotese te ondersteun.

Inquiry-based learning (IBL) is a promising educational framework that is understudied in graduate medical education. To determine participant satisfaction and engagement with phases of an IBL postgraduate education program, a mixed-methods study collected data via survey statements and open-ended responses. The authors included participants attending an intensive care medicine (ICM) IBL program from May to November 2020. Quantitative outcomes included participants' satisfaction with the IBL format and impact of engagement with IBL on the learning experience. Qualitative outcomes explored determinants of engagement with IBL phases and the impact on the learning experience. Of 378 attendees, 167 submitted survey responses (44.2%). There was strong agreement relating to overall satisfaction (93.4%). Responses indicated engagement with "orientation" (94.6%), "conceptualization" (97.3%), "discussion" (91.1%), and "conclusion" (91.0%) but limited engagement with the "investigation" phase (48.1%). Greater engagement with IBL phases had positive impacts, with repeat attenders having clearer learning objectives (79.1% vs. 56.6%, P < 0.05) and enhanced learning through collaborative discussion (65.9% vs. 48.7%, P < 0.05). Qualitative analysis showed that ICM learners value active learning principles, clear objectives, and a safe environment to expand their "knowledge base." Sessions facilitated "clinically relevant learning," with application of theoretical knowledge. Learners transformed and "reframed their understanding," using the input of others' experiences. ICM learners were highly satisfied with the IBL format and reported valuable learning. Participants engaged strongly with all IBL phases except the investigation phase during the sessions. IBL facilitated learners' active construction of meaning, facilitating a constructivist approach to learning.

The photometric properties of HgTI high intensity discharge (HID) lamps have been calculated by solving the radiation transport equations in the discharge, using the ray-tracing method. The partial pressures of the various chemical species in the plasma are computed assuming the plasma is in local thermodynamic equilibrium (LTE), using a curve fit to an experimentally measured temperature profile. The plasma is also assumed to be fully mixed, implying a constant mercury/thallium ratio throughout the discharge tube. The spectral line broadening includes neutral Van der Waals and charged particle Stark broadening. The potential influence of 'de-mixing' on the spectra is also considered. [ABSTRACT FROM AUTHOR]

Accurate integral and Lagrangian models of transport in plasmas, in which the models reflect the actual physical behaviour as closely as possible, are presented. These methods are applied to the behaviour of particles and photons in plasmas. First, to show how these types of models arise in a wide range of plasma physics applications, an application to radiation transport in a lighting discharge is given. The radiation transport is solved self-consistently with a model of the discharge to provide what are believed to be very accurate 1D simulations of fluorescent lamps. To extend these integral methods to higher dimensions is computationally very costly. The wide utility of 'treecodes' in solving massive integral problems in plasma physics is discussed, and illustrated in modelling vortex formation in a Penning trap, where a remarkably detailed simulation of vortex formation in the trap is obtained. Extension of treecode methods to other integral problems such as radiation transport is under consideration. [ABSTRACT FROM AUTHOR]

Radiation transport calculations based on the use of propagators (or Green's functions) are presented for the Hg resonance at 254 nm in the complete frequency redistribution regime. This resonance radiation plays a dominant role in the power balance of fluorescent lamps. Recent studies have suggested that transport modes above the fundamental are important in some lamp discharges. The Holstein transmittance function T(R) used to evaluate the probabilities is generated by numerical integration across the line profile at low and medium opacity. Complete hyperfine and isotopic patterns with a Voigt profile for each component are used in the model. A simple analytic expression for T(R) from a pure Lorentzian profile is used at high opacity. The calculation includes radial cataphoresis (a radial-dependent ground state Hg density). Evaluation of propagator matrix elements--probabilities of photons travelling from one cell to another--is done by integrating T(R) with the source points distributed radially across the source cell in cylindrical geometry. A radiation transport matrix or propagator function obtained from direct integration is compared with very detailed Monte Carlo simulations of radiation transport in cylindrical geometry. The probability matrix is then used in a self-consistent fluorescent lamp discharge model. Details of the numerical model are discussed. The trapped decay rates at different discharge currents and temperatures obtained by fluorescent lamp discharge simulations are compared with those calculated from an analytic formula. [ABSTRACT FROM AUTHOR]

Lay health workers have been utilized to deliver health promotion programmes in a variety of settings. However, few studies have sought to determine whether these programmes represent value for money, particularly in a UK context. The present study involved an economic evaluation of Wellbeing for Life, an integrated health and wellbeing service in northern England. The service combined one-to-one interventions delivered by lay health workers (known as health trainers), group wellbeing interventions, volunteering opportunities and other community development activities. Value for money was assessed using an established economic model developed with input from a panel of commissioners and providers, and the main data source was the national health trainer data collection and reporting system. Between June 2015 and January 2017, behaviour change outcomes (i.e. whether client goals in relation to diet, physical activity, smoking or other behaviours, had been achieved) were recorded for 2433 of the 3179 individuals who accessed one-to-one interventions. The level of achievement observed gave an estimated total health gain of 287.7 quality-adjusted life years (QALYs). In addition, there were 4669 health-promoting events, five asset mapping projects and 1595 occurrences of signposting to other services. Combining the value of individual behaviour change with the value of these additional activities gave an overall net cost per QALY gained of £3900 and a total estimated societal value of at least £3.45 for every £1 spent on the service. These results suggest that the Wellbeing for Life service offered good value for money. Further research is needed to systematically and comprehensively determine the societal value of similar holistic, asset-based and lay-led approaches., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Introduction: International health policies recognise patient empowerment, resulting in diverse empowerment models and systems. Research on organisational systems for implementing patient empowerment between countries or from organisational stakeholders' perspective, however, is limited. Aims and methodology: This paper explores and compares organisational systems and structures for patient empowerment implementation in six acute public hospitals in England and Greece (three in each country), their cross-case and cross-national similarities and differences. It uses a comparative, qualitative, explanatory embedded case study design. Semi-structured interviews with a representative sample of stakeholders (n = 33) and documentary sources (n = 79) were analysed with framework., Results: Two main patient empowerment themes were identified: (1) organisational leadership, systems, structures; (2) operational structures, services, mechanisms and activities. Generic organisational systems and structures for patient empowerment varied across-cases, but with common organisation of empowerment roles in England and common leadership in Greece. Operational structures, services and mechanisms supporting empowerment varied across-cases and cross-nationally, but with similarities in the main services., Conclusion: Implementation of patient empowerment was weaker in Greece than in England, attributable to differing approaches to strategic and operational leadership, limited development of strategies and influential organisational structures. Overall, patient empowerment is well-embedded in organisations with a highly visible patient empowerment profile; commitment to policies and strategy implementation at different levels; strategic and operational leadership investing in dedicated roles with clear authority for patient empowerment, influential empowerment structures and mechanisms.

Background: Comparison of patient empowerment (PE) policies in European countries can provide evidence for improvement and reform across different health systems. It may also influence patient and public involvement, patient experience, preference, and adherence., Objective: The objective of this study was to compare PE within national policies, systems, and structures in England and Greece for achieving integrated people-centered health services., Methods: We performed a critical search and review of policy and legislation papers in English and Greek languages. This included 1) general health policy and systems papers, 2) PE, patient and/or public involvement or patients' rights policy and legislation (1990-2015), and 3) comparative or discussion papers for England and/or Greece., Results: A total of 102 papers on PE policies, systems, and structures were identified initially; 80 papers were included, in which 46 were policy, legislative, and discussion papers about England, 21 were policy, legislation, and discussion papers about Greece, and 13 were comparative or discussion papers including both the countries. In England, National Health Service policies emphasized patient-centered services, involvement, and empowerment, with recent focus on patients' rights; while in Greece, they emphasized patients' rights and quality of services, with recent mentions on empowerment. The health ombudsman is a very important organization across countries; however, it may be more powerful in Greece, because of the nonexistence of local mediating bodies. Micro-structures at trusts/hospitals are comparable, but legislation gives more power to the local structures in Greece., Conclusion: PE policies and systems have been developed and expressed differently in these countries. However, PE similarities, comparable dimensions and mechanisms, were identified. For both the countries, comparative research and these findings could be beneficial in building connections and relationships, contributing to wider European and international developments on PE, involvement, and patients' rights and further impact on patient preferences and adherence., Competing Interests: Disclosure The authors report no conflicts of interest in this work.

Over the past 20 years, hospitalists have emerged as a distinct group of pediatric practitioners. In August of 2014, the American Board of Pediatrics (ABP) received a petition to consider recommending that pediatric hospital medicine (PHM) be recognized as a distinct new subspecialty. PHM as a formal subspecialty raises important considerations related to: (1) quality, cost, and access to pediatric health care; (2) current pediatric residency training; (3) the evolving body of knowledge in pediatrics; and (4) the impact on both primary care generalists and existing subspecialists. After a comprehensive and iterative review process, the ABP recommended that the American Board of Medical Specialties approve PHM as a new subspecialty. This article describes the broad array of challenges and certain unique opportunities that were considered by the ABP in supporting PHM as a new pediatric subspecialty., (Copyright © 2017 by the American Academy of Pediatrics.)

Importance: A strong association between infant bed sharing and sudden infant death syndrome or unintentional sleep-related death in infants has been established. Occurrences of unintentional sleep-related deaths among infants appear to be increasing., Objectives: To determine the trends and factors associated with infant bed sharing from 1993 through 2010, including the association of physician advice on bed sharing., Design: National Infant Sleep Position study conducted with annual telephone surveys., Setting: The 48 contiguous states., Participants: Nighttime caregivers of infants born within 7 months of each survey administration. Approximately 1000 interviews were completed annually., Main Outcomes and Measures: Infant bed sharing as a usual practice., Results: Of 18 986 participants, 11.2% reported an infant sharing a bed as a usual practice. Bed sharing increased from 1993 (6.5%) to 2010 (13.5%). Although bed sharing increased significantly among white respondents from 1993 to 2000 (P < .001), the increase from 2001 to 2010 was not significant (P = .48). Black and Hispanic respondents reported an increase in bed sharing throughout the study period, with no difference between the earlier and later periods (P = .63 and P = .77, respectively). After accounting for the study year, factors associated with increase in infant bed sharing as a usual practice included maternal educational level of less than high school compared with college or greater (adjusted odds ratio, 1.42 [95% CI, 1.12-1.79]); black (3.47 [2.97-4.05]), Hispanic (1.33 [1.10-1.61]), and other (2.46 [2.03-2.97]) maternal race or ethnicity compared with white race; household income of less than $20,000 (1.69 [1.44-1.99]) and $20,000 to $50,000 (1.29 [1.14-1.45]) compared with greater than $50,000; living in the West (1.61 [1.38-1.88]) or the South (1.47 [1.30-1.66]) compared with the Midwest; infants younger than 8 weeks (1.45 [1.21-1.73]) or ages 8 to 15 weeks (1.31 [1.17-1.45]) compared with 16 weeks or older; and being born prematurely compared with full-term (1.41 [1.22-1.62]). Almost 46% of the participants reported talking to a physician about bed sharing. Compared with those who did not receive advice from a physician, those who reported their physicians had a negative attitude were less likely to have the infant share a bed (adjusted odds ratio, 0.66 [95% CI, 0.53-0.82]), whereas a neutral attitude was associated with increased bed sharing (1.38 [1.05-1.80])., Conclusions and Relevance: Our finding of a continual increase in bed sharing throughout the study period among black and Hispanic infants suggests that the current American Academy of Pediatrics recommendation about bed sharing is not universally followed. The factors associated with infant bed sharing may be useful in evaluating the impact of a broad intervention to change behavior.

A study of dimethylamine photo-dissociation in the gas phase has been conducted using UV radiation delivered from a KrBr(*) excilamp, driven by a sinusoidal electronic control gear with maximum emission at wavelength of 207 nm. The electrical input power and radiant power of the lamp were measured to determine their effects on the degradation. The influence of flow velocity and initial concentration of dimethylamine were also examined. In order to evaluate the photo-dissociation process comprehensively, several parameters were investigated, including removal efficiency, energy yield, carbon balance and CO₂ selectivity. It is shown that the removal efficiency increases with enhanced input power and decreased gas flow rate. A high removal efficiency of 68% is achieved for lamp power 102W and flow velocity 15 m(3) h(-1). The optimum dimethylamine initial concentration is around 3520 mg m(-3), for which the energy yield reaches up to 442 gk Wh(-1) when the input power is 65W. In addition, two chain compounds (1,3-bis-dimethylamino-2-propanol; 3-penten-2-one, 4-amino) and three ring organic matters (1-azetidinecarboxaldehyde, 2,2,4,4-tetramethyl; N-m-tolyl-succinamic acid; p-acetoacetanisidide), were identified by GC-MS as secondary products, in order to demonstrate the pathways of the dimethylamine degradation., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Objective: To determine whether infants at sleep in the prone side positions are at higher risk for an extreme cardiorespiratory event compared with infants at sleep in the supine position., Study Design: We used a case-control study to compare sleep position, determined with an accelerometer, in 116 infants during an extreme cardiorespiratory event with that in 231 matched control subjects (2 per case) who did not experience any extreme events during monitoring., Results: From calculation of adjusted ORs and 95% CIs, infants placed in the prone or side position were no more likely to experience an extreme cardiorespiratory event compared with infants at sleep in the supine position. We used conditional logistic regression to account for the matched design of the study and to adjust for potential confounders or effect-modifiers., Conclusion: These findings, coupled with our earlier observation that the peak incidence of severe cardiorespiratory events occurred before the peak incidence of sudden infant death syndrome, strongly suggest that the supine sleeping position decreases the risk of sudden infant death syndrome by mechanisms other than by decreasing extreme cardiorespiratory events detected by monitoring., (Published by Mosby, Inc.)

Objective: To report longitudinal home recordings of hemoglobin O(2) saturation by pulse oximetry (Spo(2)) during unperturbed sleep in preterm and term infants., Study Design: We recorded continuous pulse oximetry during the first 3 minutes of each hour of monitor use (nonevent epochs) for 103 preterm infants born at <1750 g and ≤ 34 weeks postmenstrual age (PMA), and 99 healthy term infants., Results: Median baseline Spo(2) was approximately 98% for both the preterm and term groups. Episodes of intermittent hypoxemia occurred in 74% of preterm and 62% of term infants. Among infants with intermittent hypoxemia, the number of seconds/hour of monitoring <90% Spo(2) was initially significantly greater in the preterm than the term group and declined with age at a similar rate in both groups. The 75(th) to 95(th) percentiles for seconds/hour of Spo(2) <90% in preterm infants were highest at 36 weeks PMA and progressively decreased until 44 weeks PMA, after which time they did not differ from term infants., Conclusions: Clinically inapparent intermittent hypoxemia occurs in epochs unperturbed by and temporally unrelated to apnea or bradycardia events, especially in preterm infants at 36 to 44 weeks PMA., (Copyright © 2011 Mosby, Inc. All rights reserved.)

Dr. George Lister delivered the following presentation as the Lee E. Farr Lecturer on May 8, 2011, which served as the culmination of the annual Student Research Day at Yale School of Medicine. He is the Chair of Pediatrics at the University of Texas Southwestern Medical School and Pediatrician-in-Chief at Children's Medical Center of Dallas. In his lecture to the medical students, who had just completed their research theses, Dr. Lister discusses his own work on sudden infant death syndrome (SIDS), demonstrating the complexity of clinical research and proving insight into the traits required of physician scientists. Committed to medical education and recognized by several awards for his mentorship, he ends the talk by imparting valuable advice on future physicians., (Copyright © 2011.)

Objective: The American Academy of Pediatrics (AAP) strongly recommends the supine-only sleep position for infants and issued 2 more sudden infant death syndrome (SIDS) reduction recommendations: avoid bed sharing and use pacifiers during sleep. In this study, we investigated the following: 1) if mothers from at risk populations rate physicians as qualified to give advice about sleep practices and 2) if these ratings were associated with reports of recommended practice., Methods: A cross-sectional survey of mothers (N=2355) of infants aged <8 months was conducted at Women, Infants, and Children (WIC) Program centers in 6 cities from 2006 to 2008. The predictor measures were maternal rating of physician qualification to give advice about 3 recommended sleep practices and reported nature of physician advice. The dependent measures were maternal report of usage of recommended behavior: 1) "infant usually placed supine for sleep," 2) "infant usually does not share a bed with an adult during sleep," and 3) "infant usually uses a pacifier during sleep.", Results: Physician qualification ratings varied by topic: sleep position (80%), bed sharing (69%), and pacifier use (60%). High ratings of physician qualification were associated with maternal reports of recommended behavior: supine sleep (adjusted odds ratio [AOR] 2.1, 95% confidence interval [CI], 1.6-2.6); usually no bed sharing (AOR 1.5, 95% CI, 1.2-1.9), and usually use a pacifier during sleep (AOR 1.2, 95% CI, 1.0-1.5)., Conclusions: High maternal ratings of physician qualification to give advice on 2 of the 3 recommended sleep practices targeted to reduce the risk of SIDS were significantly associated with maternal report of using these behaviors. Lower ratings of physician qualification to give advice about these sleep practices may undermine physician effectiveness in promoting the recommended behavior., (Copyright © 2010 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

Objectives: To determine the relationship between the advice mothers receive about infant sleep position and the actual position they place their infants in to sleep and to understand modifiers of that relationship, especially beliefs about infant comfort and safety., Design: Cross-sectional, face-to-face interviews., Setting: Women, Infants, and Children centers in the United States from 2006 to 2008., Participants: A total of 2299 predominantly African American mothers of infants younger than 8 months., Main Exposure: Advice received and beliefs about infant sleep position., Outcome Measure: Usually supine infant sleep position., Results: Advice for exclusively supine infant sleep position from family (OR, 1.6; 95% CI, 1.17-2.17), doctors (OR, 2.28; 95% CI, 1.77-2.93), nurses (OR, 1.46; 95% CI, 1.15-1.84), or the media (OR, 1.54; 95% CI, 1.22-1.95) was associated with usually placing an infant supine to sleep. Additional sources of advice for exclusively supine position significantly increase the odds that an infant will be placed supine. Mothers who believe an infant is comfortable supine are more likely to place their infants on their backs to sleep (OR, 4.05; 95% CI, 2.51-6.53). Mothers who believe an infant will choke on its back are less likely to place their infants supine (OR, 0.36; 95% CI, 0.24-0.54)., Conclusion: Among predominantly African American mothers, increasing advice for exclusively supine sleep and addressing concerns about infant comfort and choking remain critical to getting more infants on their back to sleep.

An educational improvement audit of general practitioner (GP) training in continuity of patient care with special reference to patients with long-term conditions was commissioned by a postgraduate medical and dental deanery. The audit comprised interviews (n = 13) with GP trainers, trainees and GPs who had recently completed their training. These interviews were thematically analysed and the findings discussed in workshops with stakeholders in GP education. The interviews showed that trainers and trainees found considerable difficulty in reconciling the values of continuity of care with recent changes in policy and practice. It was also found that while training practices could demonstrate aspects of continuity of patient care, it was difficult to give trainees practical experience and responsibilities that could underline and reinforce this. Newly qualified GPs found it particularly difficult to maintain and apply their understanding of continuity of care in the realities of practice after moving on from their training practice and before obtaining a long-term GP post. The workshops formulated proposals for a series of measures to make continuity of care, in all its forms, more explicit in every element of training and in support for professional development. These proposals were analysed to develop a phased action programme and to assess their cost and utility. This showed great potential to improve the value of training in continuity of care for GP practices and trainees, and ultimately for patients.

In the 60 years since the Universal Declaration of Human Rights was promulgated, the promise of achieving respect for the human rights, health and well being of all is becoming an ever more distant prospect. We have not even remotely met the challenge of improving health for a large proportion of the world's population, and the prospects for improving global health seem to be receding in the current deteriorating economic and political climate. As global health remains one of the most pressing problems of our time, we must question the values that direct our actions and current approaches, which proclaim 'human rights to health' but which subsume these rights to a broader paradigm of unregulated global market economics and national politics, rather than working to make these oft-contradictory goals mutually compatible through justifiable and accountable global governance processes. We suggest that a new balance of values and new ways of thinking and acting are needed. These must transcend national and institutional boundaries and recognise that health in the most privileged nations is closely linked to health and disease in impoverished countries. Sustainable development of health and well-being is a necessity for all, and values for health should permeate every area of social and economic activity.

Objective: To determine trends and factors associated with choice of infant sleeping position., Design: Annual nationally representative telephone surveys from 1993 through 2007., Setting: Forty-eight contiguous states of the United States., Participants: Nighttime caregivers of infants born within the last 7 months; approximately 1000 interviews were given each year. Main Outcome Measure Whether infant is usually placed supine to sleep., Results: For the 15-year period, supine sleep increased (P < .001) and prone sleep decreased (P < .001) for all infants, with no significant difference in trend by race. Since 2001, a plateau has been reached for all races. Factors associated with increased supine sleep between 1993 and 2007 included time, maternal race other than African American, higher maternal educational level, not living in Southern states, first-born infant, and full-term infant. The effect of these variables was reduced when variables related to maternal concerns about infant comfort, choking, and advice from physicians were taken into account. Between 2003 and 2007, there was no significant yearly increase in supine sleep. Choice of sleep position could be explained almost entirely by caregiver concern about comfort, choking, and advice. Race no longer was a significant predictor., Conclusions: Since 2001, supine sleep has reached a plateau, and there continue to be racial disparities. There have been changes in factors associated with sleep position, and maternal attitudes about issues such as comfort and choking may account for much of the racial disparity in practice. To decrease sudden infant death syndrome rates, we must ensure that public health measures reach the populations at risk and include messages that address concerns about infant comfort and choking.

In 1,079 infants monitored for >700,000 hr at home for apnea or bradycardia, we found an association between infants having multiple events exceeding conventional or a priori defined more extreme thresholds and less favorable developmental outcome at 1 year of age than infants with few or no events. If it is necessary to prevent such events to minimize risk for developmental morbidity, there is reason to determine whether there are disturbances in advance of the apnea or bradycardia that herald their onset. In the 85 infants with at least 1 extreme event and 1 conventional event, we hypothesized that apnea and bradycardia do not occur de novo but rather are preceded by cardiorespiratory and hemoglobin O2 saturation changes. We compared recorded time intervals preceding these events, and we analyzed three preceding time intervals for each conventional and extreme event, and each non-event recording: Time-2 hr: up to 2 hr before; Time-1 hr: up to 1 hr before; and Time-75 sec: the 75 sec immediately preceding each event. O2 saturation progressively decreased preceding both conventional and extreme events, and progressive increases occurred in heart and breathing rate variability. Duration of respiratory pauses and of periodic breathing progressively increased preceding conventional events, respiratory rate variability increased immediately preceding conventional events and at 1 hr preceding extreme events, and O2 saturation decreased immediately preceding both conventional and extreme events. Thus, conventional and extreme events do not occur de novo but rather are preceded by autonomic instability of the cardiorespiratory system., (Copyright (c) 2007 Wiley-Liss, Inc.)

Objectives: The risk for sudden infant death syndrome in black infants is twice that of white infants, and their parents are less likely to place them in the supine position for sleep. We previously identified barriers for parents to follow recommendations for sleep position. Our objective with this study was to quantify these barriers, particularly among low-income, primarily black mothers., Design/methods: We conducted face-to-face interviews with 671 mothers, 64% of whom were black, who attended Women, Infants, and Children Program centers in Boston, Massachusetts, Dallas, Texas, Los Angeles, California, and New Haven, Connecticut. We used univariate analyses to quantify factors that were associated with choice of sleeping position and multivariate logistic regression to calculate adjusted odds ratios for the 2 outcome variables: "ever" (meaning usually, sometimes, or last night) put infant in the prone position for sleep and "usually" put infant in the supine position to sleep., Results: Fifty-nine percent of mothers reported supine, 25% side, 15% prone, and 1% other as the usual position. Thirty-four percent reported that they ever placed infants in the prone position. Seventy-two percent said that a nurse, 53% a doctor, and 38% a female friend or relative provided source of advice. Only 42% reported that a nurse, only 36% a doctor, and only 15% a female friend or relative recommended the supine position for sleep. When a female friend or relative recommended the prone position, mothers were more likely ever to place their infants in the prone position and less likely usually to choose supine compared with those who received no advice from friends or relatives. When a doctor or a nurse recommended a nonsupine position, the mothers were less likely to choose supine compared with those who received no advice from a doctor or a nurse. Mothers who trusted the opinion of a doctor or a nurse about infant sleeping position were more likely to place their infants in the supine position. Half of the mothers believed that infants were more likely to choke when supine, and they were less likely to place their infants supine. Mothers who believed that infants are more comfortable in the prone position (36%) were more likely to place their infants prone. Twenty-nine percent believed that having their infants sleep with an adult helps prevent sudden infant death syndrome, and only 43% believed that sudden infant death syndrome is related to sleeping position., Conclusions: We identified specific barriers to placing infants in the supine position for sleep (lack of or wrong advice, lack of trust in providers, knowledge and concerns about safety and comfort) in low-income, primarily black mothers that should be considered when designing interventions to get more infants onto their back for sleep.

Background: African American infants have a higher incidence of SIDS and increased risk of being placed in the prone position for sleep., Objective: To determine new barriers and more information about previously identified barriers that interfere with adherence to the Back-to-Sleep recommendations among inner-city, primarily African Americans., Design/methods: We conducted 9 focus groups with caregivers of infants and young children from women, infants, and children centers and clinics in New Haven and Boston. Themes were identified using standard qualitative techniques., Results: Forty-nine caregivers participated, of whom 86% were African American, 6% were Hispanic, 4% were white, and 4% were other. Four themes were identified: 1) SAFETY: Participants chose the position for their infants based on which position they believed to be the safest. Some participants did not choose to put their infants in the supine position for sleep because they feared their infants would choke; 2) Advice: Participants relied on the advice of more experienced female family members. Health care providers were not uniformly a trusted source of advice; 3) Comfort: Participants made choices about their infants sleeping positions based on their perceptions of whether the infants appeared comfortable. Participants thought that their infants appeared more comfortable in the prone position; 4) Knowledge: Some participants had either limited or erroneous knowledge about the Back-to-Sleep recommendations., Conclusions: We identified multiple barriers to adherence to recommendations regarding infant sleep position. Data obtained from these focus groups could be used to design educational interventions aimed at improving communication about and adherence to the Back-to-Sleep recommendations.

Background: As part of the Collaborative Home Infant Monitoring Evaluation, a home monitor was developed to record breathing, heart rate, other physiologic variables, and the time the monitor was used., Objective: To determine the frequency of monitor use, factors that influence use, and validity of a model developed to predict use., Design: We developed a model to predict monitor use using multiple linear regression analysis; we then tested the validity of this model to predict adherence for the first week of monitoring and for the subsequent 4-week period (weeks 2-5)., Setting: Clinical research centers in Chicago, Ill; Cleveland, Ohio; Honolulu, Hawaii; Los Angeles, Calif; and Toledo, Ohio. Patients Preterm infants, infants younger than 1 month with a history of autopsy-confirmed sudden infant death syndrome in a sibling, and infants with an idiopathic apparent life-threatening event were divided into 2 cohorts based on enrollment date. Main Outcome Measure Mean hours of monitor use per week., Results: In cohort 1, the variables available before monitoring were only weakly associated with total hours of monitor use in weeks 2 to 5 (total model r(2) = 0.08). However, when hours of monitor use in week 1 were included as a variable to predict monitor use in weeks 2 to 5, the r(2) increased to 0.64 for hours of monitor use per week., Conclusions: Our data show that monitor use in the first week was the most important variable for predicting subsequent monitor use. The study suggests that a major focus of home monitoring should be adherence in the first week, although it remains to be tested whether this adherence can be altered.