The New Horizons spacecraft's encounter with the cold classical Kuiper Belt object (486958) Arrokoth (provisional designation 2014 MU
) revealed a contact-binary planetesimal. We investigated how ...Arrokoth formed and found that it is the product of a gentle, low-speed merger in the early Solar System. Its two lenticular lobes suggest low-velocity accumulation of numerous smaller planetesimals within a gravitationally collapsing cloud of solid particles. The geometric alignment of the lobes indicates that they were a co-orbiting binary that experienced angular momentum loss and subsequent merger, possibly because of dynamical friction and collisions within the cloud or later gas drag. Arrokoth's contact-binary shape was preserved by the benign dynamical and collisional environment of the cold classical Kuiper Belt and therefore informs the accretion processes that operated in the early Solar System.
Introduction Direct-to-consumer m Health devices are a potential asset to behavioral research but rarely tested as intervention tools. This trial examined the accelerometer-based Fitbit tracker and ...website as a low-touch physical activity intervention. The purpose of this study is to evaluate, within an RCT, the feasibility and preliminary efficacy of integrating the Fitbit tracker and website into a physical activity intervention for postmenopausal women. Methods Fifty-one inactive, postmenopausal women with BMI ≥25.0 were randomized to a 16-week web-based self-monitoring intervention ( n =25) or comparison group ( n =26). The Web-Based Tracking Group received a Fitbit, instructional session, and follow-up call at 4 weeks. The comparison group received a standard pedometer. All were asked to perform 150 minutes/week of moderate to vigorous physical activity (MVPA). Physical activity outcomes were measured by the ActiGraph GT3X+ accelerometer. Results Data were collected and analyzed in 2013–2014. Participants were aged 60 (SD=7) years with BMI of 29.2 (3.5) kg/m2 . Relative to baseline, the Web-Based Tracking Group increased MVPA by 62 (108) minutes/week ( p <0.01); 10-minute MVPA bouts by 38 (83) minutes/week ( p =0.008); and steps by 789 (1,979) ( p =0.01), compared to non-significant increases in the Pedometer Group (between-group p =0.11, 0.28, and 0.30, respectively). The Web-Based Tracking Group wore the tracker on 95% of intervention days; 96% reported liking the website and 100% liked the tracker. Conclusions The Fitbit was well accepted in this sample of women and associated with increased physical activity at 16 weeks. Leveraging direct-to-consumer m Health technologies aligned with behavior change theories can strengthen physical activity interventions.
Background
This is the second update of a Cochrane Review (Issue 4, 2006). Pain and distress from needle‐related procedures are common during childhood and can be reduced through use of psychological ...interventions (cognitive or behavioral strategies, or both). Our first review update (Issue 10, 2013) showed efficacy of distraction and hypnosis for needle‐related pain and distress in children and adolescents.
Objectives
To assess the efficacy of psychological interventions for needle‐related procedural pain and distress in children and adolescents.
Search methods
We searched six electronic databases for relevant trials: Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE; PsycINFO; Embase; Web of Science (ISI Web of Knowledge); and Cumulative Index to Nursing and Allied Health Literature (CINAHL). We sent requests for additional studies to pediatric pain and child health electronic listservs. We also searched registries for relevant completed trials: clinicaltrials.gov; and World Health Organization International Clinical Trials Registry Platform (www.who.int.trialsearch). We conducted searches up to September 2017 to identify records published since the last review update in 2013.
Selection criteria
We included peer‐reviewed published randomized controlled trials (RCTs) with at least five participants per study arm, comparing a psychological intervention with a control or comparison group. Trials involved children aged two to 19 years undergoing any needle‐related medical procedure.
Data collection and analysis
Two review authors extracted data and assessed risks of bias using the Cochrane 'Risk of bias' tool. We examined pain and distress assessed by child self‐report, observer global report, and behavioral measurement (primary outcomes). We also examined any reported physiological outcomes and adverse events (secondary outcomes). We used meta‐analysis to assess the efficacy of identified psychological interventions relative to a comparator (i.e. no treatment, other active treatment, treatment as usual, or waitlist) for each outcome separately. We used Review Manager 5 software to compute standardized mean differences (SMDs) with 95% confidence intervals (CIs), and GRADE to assess the quality of the evidence.
Main results
We included 59 trials (20 new for this update) with 5550 participants. Needle procedures primarily included venipuncture, intravenous insertion, and vaccine injections. Studies included children aged two to 19 years, with few trials focused on adolescents. The most common psychological interventions were distraction (n = 32), combined cognitive behavioral therapy (CBT; n = 18), and hypnosis (n = 8). Preparation/information (n = 4), breathing (n = 4), suggestion (n = 3), and memory alteration (n = 1) were also included. Control groups were often 'standard care', which varied across studies. Across all studies, 'Risk of bias' scores indicated several domains at high or unclear risk, most notably allocation concealment, blinding of participants and outcome assessment, and selective reporting. We downgraded the quality of evidence largely due to serious study limitations, inconsistency, and imprecision.
Very low‐ to low‐quality evidence supported the efficacy of distraction for self‐reported pain (n = 30, 2802 participants; SMD −0.56, 95% CI −0.78 to −0.33) and distress (n = 4, 426 participants; SMD −0.82, 95% CI −1.45 to −0.18), observer‐reported pain (n = 11, 1512 participants; SMD −0.62, 95% CI −1.00 to −0.23) and distress (n = 5, 1067 participants; SMD −0.72, 95% CI −1.41 to −0.03), and behavioral distress (n = 7, 500 participants; SMD −0.44, 95% CI −0.84 to −0.04). Distraction was not efficacious for behavioral pain (n = 4, 309 participants; SMD −0.33, 95% CI −0.69 to 0.03). Very low‐quality evidence indicated hypnosis was efficacious for reducing self‐reported pain (n = 5, 176 participants; SMD −1.40, 95% CI −2.32 to −0.48) and distress (n = 5, 176 participants; SMD −2.53, 95% CI −3.93 to −1.12), and behavioral distress (n = 6, 193 participants; SMD −1.15, 95% CI −1.76 to −0.53), but not behavioral pain (n = 2, 69 participants; SMD −0.38, 95% CI −1.57 to 0.81). No studies assessed hypnosis for observer‐reported pain and only one study assessed observer‐reported distress. Very low‐ to low‐quality evidence supported the efficacy of combined CBT for observer‐reported pain (n = 4, 385 participants; SMD −0.52, 95% CI −0.73 to −0.30) and behavioral distress (n = 11, 1105 participants; SMD −0.40, 95% CI −0.67 to −0.14), but not self‐reported pain (n = 14, 1359 participants; SMD −0.27, 95% CI −0.58 to 0.03), self‐reported distress (n = 6, 234 participants; SMD −0.26, 95% CI −0.56 to 0.04), observer‐reported distress (n = 6, 765 participants; SMD 0.08, 95% CI −0.34 to 0.50), or behavioral pain (n = 2, 95 participants; SMD −0.65, 95% CI −2.36 to 1.06). Very low‐quality evidence showed efficacy of breathing interventions for self‐reported pain (n = 4, 298 participants; SMD −1.04, 95% CI −1.86 to −0.22), but there were too few studies for meta‐analysis of other outcomes. Very low‐quality evidence revealed no effect for preparation/information (n = 4, 313 participants) or suggestion (n = 3, 218 participants) for any pain or distress outcome. Given only a single trial, we could draw no conclusions about memory alteration. Adverse events of respiratory difficulties were only reported in one breathing intervention.
Authors' conclusions
We identified evidence supporting the efficacy of distraction, hypnosis, combined CBT, and breathing interventions for reducing children’s needle‐related pain or distress, or both. Support for the efficacy of combined CBT and breathing interventions is new from our last review update due to the availability of new evidence. The quality of trials and overall evidence remains low to very low, underscoring the need for improved methodological rigor and trial reporting. Despite low‐quality evidence, the potential benefits of reduced pain or distress or both support the evidence in favor of using these interventions in clinical practice.
We measure the change in household spending caused by receipt of the economic stimulus payments of 2008, using questions added to the Consumer Expenditure Survey and variation from the randomized ...timing of disbursement. Households spent 12–30 percent (depending on specification) of their payments on nondurable goods during the three-month period of payment receipt, and a significant amount more on durable goods, primarily vehicles, bringing the total response to 50–90 percent of the payments. The responses are substantial and significant for older, lower-income, and home-owning households. Spending does not vary significantly with the method of disbursement (check versus electronic transfer). (JEL D12, D14, E21, E62)
When compared to meniscectomy, meniscus allograft transplantation (MAT) may provide superior long-term benefits to young, active patient populations who have lost meniscal function because of ...irreparable damage, such as, an avascular tear, previous repair failure, and unsalvageable tear types. Positive outcomes are most likely to be achieved when meniscus allograft transplantation is performed in appropriately selected patients. Indications include patients younger than 50 years of age, with a history of subtotal or total meniscectomy without concomitant articular cartilage defects, uncorrectable joint malalignment, and/or knee instability. Outcomes for meniscal allograft transplantation are promising with studies reporting long-term graft survivorship as high as 89% at 10 years and significant improvements in multiple patient reported outcome measures.
Level of evidence
Level V.
Polyandry: the history of a revolution Parker, Geoff A.; Birkhead, Tim R.
Philosophical transactions of the Royal Society of London. Series B. Biological sciences,
03/2013, Letnik:
368, Številka:
1613
Journal Article
Recenzirano
Odprti dostop
We give a historic overview and critical perspective of polyandry in the context of sexual selection. Early approaches tended to obfuscate the fact that the total matings (copulations) by the two ...sexes is equal, neglecting female interests and that females often mate with (or receive ejaculates from) more than one male (polyandry). In recent years, we have gained much more insight into adaptive reasons for polyandry, particularly from the female perspective. However, costs and benefits of multiple mating are unlikely to be equal for males and females. These must be assessed for each partner at each potential mating between male i and female j, and will often be highly asymmetric. Interests of i and j may be in conflict, with (typically, ultimately because of primordial sex differences) i benefitting and j losing from mating, although theoretically the reverse can also obtain. Polyandry reduces the sex difference in Bateman gradients, and the probability of sexual conflict over mating by: (i) reducing the potential expected value of each mating to males in inverse proportion to the number of mates per female per clutch, and also often by (ii) increasing ejaculate costs through increased sperm allocation. It can nevertheless create conflict over fertilization and increase conflict over parental investment. The observed mean mating frequency for the population (and hence the degree of polyandry) is likely, at least in part, to reflect a resolution of sexual conflict. Immense diversity exists across and within taxa in the extent of polyandry, and views on its significance have changed radically, as we illustrate using avian polyandry as a case study. Despite recent criticisms, the contribution of the early pioneers of sexual selection, Darwin and Bateman, remains generally valid, and should not, therefore, be negated; as with much in science, pioneering advances are more often amplified and refined, rather than replaced with entirely new paradigms.
Abstract Background Preventing relapse is an essential element of early intervention in psychosis, but relevant risk factors and precise relapse rates remain to be clarified. The aim of this study ...was to systematically compile and analyse risk factors for and rates of relapse in the early course of psychosis. Methods Systematic review and meta-analysis of English and non-English language, peer-reviewed, longitudinal studies, with a minimum 12-month follow-up and at least 80% of participants diagnosed with a first episode of psychosis (FEP) that reported risk factors for relapse. Results Of 153 potentially relevant articles, 29 were included in the study. Pooled prevalence of relapse of positive symptoms was 28% (range = 12–47%), 43% (35–54%), 54% (40–63%) at 1, 1.5–2, and 3 years follow-up, in that order. A total of 109 predictors were analysed, with 24 being assessed in at least 3 studies. Of those, 20 predictors could be extracted for meta-analysis. Medication non-adherence, persistent substance use disorder, carers' critical comments (but not overall expressed emotion) and poorer premorbid adjustment, increased the risk for relapse 4-fold, 3-fold, 2.3-fold and 2.2-fold, respectively. Conclusions Clinical variables and general demographic variables have little impact on relapse rates. Conversely, non-adherence with medication, persistent substance use disorder, carers' criticism and poorer premorbid adjustment significantly increase the risk for relapse in FEP. Future studies need to address the methodological limitations of the extant research (e.g. definition of relapse), focus on the identification of protective factors and evaluate theoretically derived models of relapse.
Though the first attempts to introduce game theory into evolutionary biology failed, new formalism by Maynard Smith and Price in 1973 had almost instant success. We use information supplied by early ...workers to analyse how and why evolutionary game theory (EGT) spread so rapidly in its earliest years. EGT was a major tool for the rapidly expanding discipline of behavioural ecology in the 1970s; each catalysed the other. The first models were applied to animal contests, and early workers sought to improve their biological reality to compare predictions with observations. Furthermore, it was quickly realized that EGT provided a general evolutionary modelling method; not only was it swiftly applied to diverse phenotypic adaptations in evolutionary biology, it also attracted researchers from other disciplines such as mathematics and economics, for which game theory was first devised. Lastly, we pay attention to exchanges with population geneticists, considering tensions between the two modelling methods, as well as efforts to bring them closer. This article is part of the theme issue 'Half a century of evolutionary games: a synthesis of theory, application and future directions'.
Although the study of nonradiating anapoles has long been part of fundamental physics, the dynamic anapole at optical frequencies was only recently experimentally demonstrated in a specialized ...silicon nanodisk structure. We report excitation of the electrodynamic anapole state in isotropic silicon nanospheres using radially polarized beam illumination. The superposition of equal and out-of-phase amplitudes of the Cartesian electric and toroidal dipoles produces a pronounced dip in the scattering spectra with the scattering intensity almost reaching zero-a signature of anapole excitation. The total scattering intensity associated with the anapole excitation is found to be more than 10 times weaker for illumination with radially vs linearly polarized beams. Our approach provides a simple, straightforward alternative path to realizing nonradiating anapole states at the optical frequencies.
Recently, the Blinding of Trial Statisticians research team, Iflaifel and colleagues, have produced detailed guidance regarding the blinding or unblinding of statisticians in clinical trials, based ...on substantial mixed-methods work. I wish to comment on the research findings. In particular, I argue that open-label trials, non-drug trials, or non-inferiority trials should not be treated any differently from blinded superiority trials with regards to the risk of bias assessment. Prevention of bias should be the priority for definitive randomised controlled trials, regardless of the precise study design.
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