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In a crossover trial, a gown designed to increase skin coverage at the hands and wrists significantly reduced contamination of personnel during personal protective equipment (PPE) removal, and education on donning and doffing technique further reduced contamination. Simple modifications of PPE and education can reduce contamination during PPE removal.
Introduction: Intravenous insertion (IVI) is identified by children as extremely painful and the resultant distress can have lasting negative consequences. There is an urgent need to effectively manage such procedures. Our primary objective was to compare the pain and distress of IVI with the addition of humanoid robot-based distraction to standard care, versus standard care alone. Methods: This two-armed randomized controlled trial (RCT) was conducted from April 2017 to May 2018 at the Stollery Children's Hospital emergency department (ED). Children aged 6 to 11 years who required IVI were included. Exclusion criteria included hearing or visual impairments, neurocognitive delays, sensory impairment to pain, previous enrolment, and discretion of the ED clinical staff. Primary outcomes were measured using the Observational Scale of Behavioural Distress-Revised (OSBD-R) (distress) and the Faces Pain Scale-Revised (FPS-R) (pain). A total of 426 pediatric patients were screened and 340 were excluded. Results: We recruited 86 children, of which 55% (47/86) were male; 9% (7/82) were premature at birth; 82% (67/82) had a previous ED visit; 30% (25/82) required previous hospitalization; 78% (64/82) had previous IV placement and 96% (78/81) received topical anesthesia. The mean total OSBD-R score was 1.49 ± 2.36 (standard care) compared to 0.78 ± 1.32 (robot group) (p = 0.047). The median FPS-R during the IV procedure was 4 (IQR 2,6) in the standard care group alone, compared to 2 (IQR 0,4) with the addition of humanoid robot-based distraction (p = 0.10). Change in parental state anxiety pre-procedure versus post-procedure was not significantly different between groups (p = 0.49). Parental satisfaction with the IV start was 93% (39/42) in the robot arm compared to 74% (29/39) in the standard care arm (p = 0.03). Parents were also more satisfied with management of their child's pain in the robot group (95% very satisfied) compared with standard care (72% very satisfied) (p = 0.002). Conclusion: A statistically significant reduction in distress was observed with the addition of robot-based distraction to standard care. Humanoid robot-based distraction therapy reduces distress and to a lesser extent, pain, in children undergoing IVI in the ED. Further trials are required to confirm utility in other age groups and settings.
We describe the production of photovoltaic modules with high-quality large-grain copper indium gallium selenide (CIGS) thin films obtained with the unique combination of low-cost ink-based precursors and a reactive transfer printing method. The proprietary metal-organic inks contain a variety of soluble Cu-, In- and Ga- multinary selenide materials; they are called metal-organic decomposition (MOD) precursors, as they are designed to decompose into the desired precursors. Reactive transfer is a two-stage process that produces CIGS through the chemical reaction between two separate precursor films, one deposited on the substrate and the other on a printing plate in the first stage. In the second stage, these precursors are rapidly reacted together under pressure in the presence of heat. The use of two independent thin films provides the benefits of independent composition and flexible deposition technique optimization, and eliminates pre-reaction prior to the synthesis of CIGS. In a few minutes, the process produces high quality CIGS films, with large grains on the order of several microns, and preferred crystallographic orientation, as confirmed by compositional and structural analysis by XRF, SIMS, SEM and XRD. Cell efficiencies of 14% and module efficiencies of 12% were achieved using this method. The atmospheric deposition processes include slot die extrusion coating, ultrasonic atomization spraying, pneumatic atomization spraying, inkjet printing, direct writing, and screen printing, and provide low capital equipment cost, low thermal budget, and high throughput.
Schizophrenia and anorexia nervosa were recently added to the list of conditions for which whole genome sequencing might be indicated as part of the 100 000 Genomes Project, reflecting the remarkable recent progress in findings emerging from psychiatric genetics research. Genetic testing methods may offer increased opportunities for diagnosis and estimation of familial risk and could have implications for management and treatment options. They also present ethical and philosophical questions about the role of testing and storage of genetic information. Mental health professionals will need to have a good understanding of this area in order for patients to fully realise the benefits of these advances.
Declaration of Interest
K.S.B. is Editor of the British Journal of Psychiatry.
Problematic alcohol use is associated with detrimental cognitive, physiological and social consequences. In the emergency department (ED), Screening, Brief Intervention, and Referral to Treatment (SBIRT) is the recommended approach to identify and treat adolescent alcohol-related concerns, but is underused by physicians.
This study examined pediatric emergency physicians’ perceptions of adolescent drinking and treatment, and their current self-reported SBIRT practices.
Physicians in the Pediatric Emergency Research Canada database (n=245) received a 35-item questionnaire that was administered through a web-based platform and paper-based mail-outs. Recruitment followed a modified Dillman four-contact approach.
From October 2016 to January 2017, 166 pediatric emergency physicians (46.4% males; mean age=43.6 years) completed the questionnaire. The response rate was 67.8%. Physicians recognized the need (65%) and responsibility (86%) to address adolescent alcohol problems. However, confidence in knowledge and abilities for SBIRT execution was low. Twenty-five percent of physicians reported never having practiced all, or part of, SBIRT while 1.3% reported consistent SBIRT delivery for adolescents with alcohol-related visits. More alcohol education and counselling experience was associated with higher SBIRT use; however, physicians generally reported to have received minimal alcohol training. SBIRT practices were also associated with physician perceptions of problematic alcohol use and its treatability.
Pediatric emergency physicians acknowledge the need to address problematic adolescent alcohol use, but routine SBIRT use is lacking. Strategies to educate physicians about SBIRT and enhance perceived self-competency may improve SBIRT use. Effectiveness trials to establish SBIRT impact on patient outcomes are also needed.
Introduction: Intravenous (IV) cannulation is commonly performed in emergency departments (ED), often causing substantial pain and distress. Distraction has been shown to reduce child-reported pain, but there is currently little published about the effects of using iPad technology as a distraction tool. Our primary objective was to compare the reduction of pain and distress using iPad distraction (games, movies, books of the child’s choice) in addition to standard care, versus standard care alone. Methods: This randomized clinical trial, conducted at the Stollery Childrens Hospital ED, recruited children between ages 6 to 11 years requiring IV cannulation. Study arm assignment was performed using REDCaps randomization feature. Due to the nature of the intervention, blinding was not possible for the children, parents or research and ED staff, but the data analyst was blinded to intervention assignment until completion of analysis. Pain, distress, and parental anxiety were measured using the Faces Pain Scale-Revised, the Observed Scale of Behavioural Distress-Revised, and the State Trait Anxiety Inventory, respectively. The pain scores and observed behavioural distress scores were compared using the Mann-Whitney U test. Other co-variates were analyzed using a linear regression analysis. Results: A total of 85 children were enrolled, with 42 receiving iPad distraction and 43 standard care, of which 40 (95%) and 35 (81%) children received topical anesthesia, respectively (p=0.09). There were 40 girls (47.1%) with a mean age of 8.32 +/− 1.61 years. The pain scores during IV cannulation (p=0.35) and the change in pain score during the procedure compared to baseline (p=0.79) were not significantly different between the groups, nor were the observed distress scores during IV cannulation (p=0.09), or the change in observed distress during the procedure compared to baseline (p=0.44). A regression analysis showed children in both groups had greater total behavioural stress if it was their first ED visit (p=0.01), had prior hospitalization experience (p=0.04) or were admitted to hospital during this visit (p=0.007). A previous ED visit, however, was predictive of a greater increase in parental anxiety from baseline (p=0.02). When parents were asked whether they would use the same methods to manage pain for their child, parents of the iPad group were more likely to say yes than were parents of the standard care group (p=0.03). Conclusion: iPad distraction during IV cannulation in school-aged children was not found to decrease pain or distress more than standard care alone, but parents preferred its use. The effects of iPad distraction may have been over-shadowed by potent topical anesthetic effect. Future directions include exploring iPad distraction for other age groups, and studying novel technology such as virtual reality and interactive humanoid robots.
The aim of this study was to investigate the association between maternal sensitivity and offspring intelligence in late childhood and adolescence. Secondary data (N=117) from the Block and Block (2006a, b) 30-year longitudinal study of Californian children, which began in the late 1960s, was used to test the hypothesis that maternal sensitivity in childhood would be predictive of late childhood and adolescent intelligence. Correlational analyses revealed that maternal sensitivity, as judged by raters viewing mother’s interactions with their children in a set of four joint structured cognitive tasks when the child was 5 years of age, was associated with verbal and performance IQ test scores when the children were ages 11 and 18. Using hierarchical regression to control for child sex, socioeconomic status, child temperament, child baseline IQ (as measured at age 4), mother’s level of education and mother’s emotional nurturance, it was found that the maternal sensitivity and child and adolescent IQ association held for verbal, but not performance IQ. Furthermore, a pattern emerged in which the association between maternal sensitivity and verbal IQ was stronger for adolescents with a lower baseline IQ. The results suggest that maternal sensitivity is associated with offspring verbal intelligence and that this association holds when numerous variables are accounted for. Additionally, this association may be stronger for children with lower IQs.
In a randomized trial, a gown designed to allow easy removal at the neck and with increased skin coverage and snugness of fit at the wrist significantly reduced contamination of personnel during personal protective equipment (PPE) removal. Our results suggest that simple modifications of PPE can reduce contamination of personnel.
At weaning, piglets must adapt to considerable changes in their environmental, immunological, and nutritional status. This period of adaptation is accompanied by a reduction in piglet growth rate that has been associated with the shift from sow’s milk to a solid dry diet. Consequently, feeding management strategies that result in increased feed intake may increase piglet growth rate postweaning. This study evaluated the effects of providing feed as a gruel and feeding on floor mats on piglet performance for three weeks after weaning
When emptying finishing barns, it is common practice on U.S. operations to dispatch pigs over a two- to three-week period with the heaviest animals being selected first. However, there has been little research carried out under commercial conditions on the effect of removing pigs from a pen at slaughter weight on the performance of the remaining animals. This study was carried out to investigate the effect of removing the heaviest 30% of animals from a pen on the subsequent growth performance of the remaining pigs.
Wean-to-finish production, which involves taking pigs from weaning to slaughter in the same building, is becoming widely adopted in the US swine industry. This production system is being advocated largely because of claims of improved animal performance and a decrease in labor needed for animal movement compared to conventional multiple-stage systems. One of the potential disadvantages of this system is the considerable underutilization of floor space during the early growth period if pigs are penned in the group sizes that are appropriate for finishing pigs. However, increasing the stocking rate initially at weaning, with some of these pigs subsequently being moved to another finishing facility, may increase output from the system. Therefore, the objective of this research was to investigate effects of initial stocking rate and of feeder-trough space in commercial wean-to-finish facilities on pig performance from weaning to slaughter.
Three-dimensional (3D) printing has expanded beyond the mere patterned deposition of melted solids, moving into areas requiring spatially structured soft matter—typically materials composed of polymers, colloids, surfactants, or living cells. The tunable and dynamically variable rheological properties of soft matter enable the high-resolution manufacture of soft structures. These rheological properties are leveraged in 3D printing techniques that employ sacrificial inks and sacrificial support materials, which go through reversible solid–fluid transitions under modest forces or other small perturbations. Thus, a sacrificial material can be used to shape a second material into a complex 3D structure, and then discarded. Here, we review the sacrificial materials and related methods used to print soft structures. We analyze data from the literature to establish manufacturing principles of soft matter printing, and we explore printing performance within the context of instabilities controlled by the rheology of soft matter materials.
Transcending reviewed proximate theories, Van Lange et al.'s CLASH model attempts to ultimately explain the poleward declension of aggression and violence. Seasonal cold is causal, but, we contend, principally as an ecologically relevant evolutionary pressure. We further argue that futurity and restraint are life history variables, and that Life History Theory evolutionarily explains the biogeography of aggression and violence as strategic adaptation.
The problem of orthogonal penetration of a blade into the core of a vortex with non-zero axial flow was studied using a combination of scaling theory, a heuristic plug-flow model and full Navier–Stokes simulations. The particular focus of this paper was to understand the mechanics of the transient lift force that occurs during the initial penetration of the blade leading edge into the vortex core, and the relationship of this transient force to the steady-state lift force that develops due to the difference in vortex core radius over the blade surface. The three modelling approaches all lead to the conclusion that the maximum value of the lift coefficient for the transient blade penetration force is proportional to the impact parameter and inversely proportional to the axial flow parameter. This observation is used to develop a simple expression that collapses the predictions of the full Navier–Stokes simulations for lift coefficient over a wide range of parameter values.
We demonstrate that the expected value and variance commonly given for a well-known probability distribution are incorrect. We also provide corrected versions and report changes in a computer program to account for the known practical uses of this distribution.
The probability distribution in question, named the continuous parameter binomial (CPB) by King (1989a), has been known for at least six decades. The publications that reported the moments incorrectly, or were at least unclear about them, include a dated article (Guldberg 1931), a dissertation and several resulting published articles (Katz 1945, 1965), a popular reference book (Johnson and Kotz 1969),' work in political science on event count regression models (King 1989a), and extensions of these event count models in econometrics (Winkelmann and Zimmermann 1991). Event count regression models have become increasingly common in empirical political science research; some recent examples include Wang et al. (1993) and Krause (1994).
Since Beck, Katz, and Tucker (1998), the standard method for modeling time dependence in binary data has been to incorporate time dummies or splined time in logistic regressions. Although we agree with the need for modeling time dependence, we demonstrate that time dummies can induce estimation problems due to separation. Splines do not suffer from these problems. However, the complexity of splines has led substantive researchers (1) to use knot values that may be inappropriate for their data and (2) to ignore any substantive discussion concerning temporal dependence. We propose a relatively simple alternative: including t, t2, and t3 in the regression. This cubic polynomial approximation is trivial to implement—and, therefore, interpret—and it avoids problems such as quasi-complete separation. Monte Carlo analysis demonstrates that, for the types of hazards one often sees in substantive research, the polynomial approximation always outperforms time dummies and generally performs as well as splines or even more flexible autosmoothing procedures. Due to its simplicity, this method also accommodates nonproportional hazards in a straightforward way. We reanalyze Crowley and Skocpol (2001) using nonproportional hazards and find new empirical support for the historical-institutionalist perspective.
Binary, count, and duration data all code discrete events occurring at points in time. Although a single data generation process can produce all of these three data types, the statistical literature is not very helpful in providing methods to estimate parameters of the same process from each. In fact, only a single theoretical process exists for which known statistical methods can estimate the same parameters—and it is generally used only for count and duration data. The result is that seemingly trivial decisions about which level of data to use can have important consequences for substantive interpretations. We describe the theoretical event process for which results exist, based on time independence. We also derive a set of models for a time-dependent process and compare their predictions to those of a commonly used model. Any hope of understanding and avoiding the more serious problems of aggregation bias in events data is contingent on first deriving a much wider arsenal of statistical models and theoretical processes that are not constrained by the particular forms of data that happen to be available. We discuss these issues and suggest an agenda for political methodologists interested in this very large class of aggregation problems.
We thank Neal Beck for his comments. In general, there is little difference in our theoretical and practical positions. We all agree that in some applications, time dummies can be problematic; controlling for temporal dependence is important for less-biased estimation of the coefficients on our substantive regressors; a smoothed function of time (whether via a cubic polynomial or spline) is a useful way to model temporal dependence in grouped binary data; and viewing the graph of the hazard can be informative.
Social scientists are often confronted with theories in which one or more actors make choices over a discrete set of options. In this article, I generalize a broad class of statistical discrete choice models, with both well-known and new nonstrategic and strategic special cases. I demonstrate how to derive statistical models from theoretical discrete choice models and, in doing so, I address the statistical implications of three sources of uncertainty: agent error, private information about payoffs, and regressor error. For strategic and some nonstrategic choice models, the three types of uncertainty produce different statistical models. In these cases, misspecifying the type of uncertainty leads to biased and inconsistent estimates, and to incorrect inferences based on estimated probabilities.