Increase In Proportion Of Time Research Articles

Investigating the developmental timing of self-regulation in early childhood

Self-regulation often refers to the executive influence of cognitive resources to alter prepotent responses. The ability to engage cognitive resources as a form of executive process emerges and improves in the preschool-age years while the dominance of prepotent responses, such as emotional reactions, begins to decline from toddlerhood onward. However, little direct empirical evidence addresses the timing of an age-related increase in executive processes and a decrease in age-related prepotent responses over the course of early childhood. To address this gap, we examined children’s individual trajectories of change in prepotent responses and executive processes over time. At four age points (24 months, 36 months, 48 months, and 5 years), we observed children (46% female) during a procedure in which mothers were busy with work and told their children they had to wait to open a gift. Prepotent responses included children’s interest in and desire for the gift and their anger about the wait. Executive processes included children’s use of focused distraction, which is the strategy considered optimal for self-regulation in a waiting task. We examined individual differences in the timing of age-related changes in the proportion of time spent expressing a prepotent response and engaging executive processes using a series of nonlinear (generalized logistic) growth models. As hypothesized, the average proportion of time children expressed prepotent responses decreased with age, and the average proportion of time engaged in executive processes increased with age. Individual differences in the developmental timing of changes in prepotent responses and executive process were correlated r = .35 such that the timing of decrease in proportion of time expressing prepotent responses was coupled with the timing of increase in proportion of time engaging executive processes.

Multicenter Retrospective Review of Ketamine Use in the ICU.

IMPORTANCE:The response of ICU patients to continuously infused ketamine when it is used for analgesia and/or sedation remains poorly established.OBJECTIVES:To describe continuous infusion (CI) ketamine use in critically ill patients, including indications, dose and duration, adverse effects, patient outcomes, time in goal pain/sedation score range, exposure to analgesics/sedatives, and delirium.DESIGN, SETTING, AND PARTICIPANTS:Multicenter, retrospective, observational study from twenty-five diverse institutions in the United States. Patients receiving CI ketamine between January 2014 and December 2017.MAIN OUTCOMES AND MEASURES:Chart review evaluating institutional and patient demographics, ketamine indication, dose, administration, and adverse effects. Pain/sedation scores, cumulative doses of sedatives and analgesics, and delirium screenings in the 24 hours prior to ketamine were compared with those at 0–24 hours and 25–48 hours after.RESULTS:A total of 390 patients were included (median age, 54.5 yr; interquartile range, 39–65 yr; 61% males). Primary ICU types were medical (35.3%), surgical (23.3%), and trauma (17.7%). Most common indications were analgesia/sedation (n = 357, 91.5%). Starting doses were 0.2 mg/kg/hr (0.1–0.5 mg/kg/hr) and continued for 1.6 days (0.6–2.9 d). Hemodynamics in the first 4 hours after ketamine were variable (hypertension 24.0%, hypotension 23.5%, tachycardia 19.5%, bradycardia 2.3%); other adverse effects were minimal. Compared with 24 hours prior, there was a significant increase in proportion of time spent within goal pain score after ketamine initiation (24 hr prior: 68.9% [66.7–72.6%], 0–24 hr: 78.6% [74.3–82.5%], 25–48 hr: 80.3% [74.6–84.3%]; p < 0.001) and time spent within goal sedation score (24 hr prior: 57.1% [52.5–60.0%], 0–24 hr: 64.1% [60.7–67.2%], 25–48 hr: 68.9% [65.5–79.5%]; p < 0.001). There was also a significant reduction in IV morphine (mg) equivalents (24 hr prior: 120 [25–400], 0–24 hr: 118 [10–363], 25–48 hr: 80 [5–328]; p < 0.005), midazolam (mg) equivalents (24 hr prior: 11 [4–67], 0–24 hr: 6 [0–68], 25–48 hr: 3 [0–57]; p < 0.001), propofol (mg) (24 hr prior: 942 [223–4,018], 0–24 hr: 160 [0–2,776], 25–48 hr: 0 [0–1,859]; p < 0.001), and dexmedetomidine (µg) (24 hr prior: 1,025 [276–1,925], 0–24 hr: 285 [0–1,283], 25–48 hr: 0 [0–826]; p < 0.001). There was no difference in proportion of time spent positive for delirium (24 hr prior: 43.0% [17.0–47.0%], 0–24 hr: 39.5% [27.0–43.8%], 25–48 hr: 0% [0–43.7%]; p = 0.233). Limitations to these data include lack of a comparator group, potential for confounders and selection bias, and varying pain and sedation practices that may have changed since completion of the study.CONCLUSIONS AND RELEVANCE:There is variability in the use of CI ketamine. Hemodynamic instability was the most common adverse effect. In the 48 hours after ketamine initiation compared with the 24 hours prior, proportion of time spent in goal pain/sedation score range increased and exposure to other analgesics/sedatives decreased.

Pattern Analysis of Sedentary Behavior Change after a Walking Intervention.

We examined the pattern of change in sedentary behavior (SB) resulting from a physical activity (PA) intervention in older adults, and the influence of sex on changes in SB. One hundred twenty (N = 120) inactive older adults from 2 12-week step/day-target interventions were included in this pooled reanalysis. Participants were randomly assigned to an intervention (STEP) or control group (CON). A Hip-worn accelerometer (Actigraph) was used to assess SB and PA. Significant decreases in SB (-25 minutes) were largely accounted for by the increase in moderate- to vigorous-intensity PA (MVPA; +17.3 minutes). More broadly, data showed that for every 1% increase in proportion of time spent in MVPA, SB decreased by 1.21%. Results of the pattern analysis showed significant pre-post decreases in the number of daily sedentary bouts lasting 10, 20, and 30 minutes and the number of sit-to-stand transitions in the STEP group. Males tended to decrease time spent in longer bouts and females tended to decrease the number of sit-to-stand transitions to achieve lower SB. Decreases in SB were accomplished through reductions in shorter bouts of SB and likely through a variety of small changes that differed between individual participants and sexes.

Seasonal variation of depressive symptoms in unipolar major depressive disorder

ObjectivesRetrospective and cross-sectional studies of seasonal variation of depressive symptoms in unipolar major depression have yielded conflicting results. We examined seasonal variation of mood symptoms in a long-term prospective cohort – the Collaborative Depression Study (CDS). MethodsThe sample included 298 CDS participants from five academic centers with a prospectively derived diagnosis of unipolar major depression who were followed for at least ten years of annual or semi-annual assessments. Generalized linear mixed models were utilized to investigate the presence of seasonal patterns. In a subset of 271 participants followed for at least 20years, the stability of a winter depressive pattern was assessed across the first two decades of follow-up. ResultsA small increase in proportion of time depressed was found in the months surrounding the winter solstice, although the greatest symptom burden was seen in December through April with a peak in March. The relative burden of winter depressive symptoms in the first decade demonstrated no relationship to that of the second decade. The onset of new episodes was highest October through January, peaking in January. ConclusionsThere exists a small but statistically significant peak in depressive symptoms from the month of the winter solstice to the month of the spring equinox. However, the predominance of winter depressive symptoms did not appear stable over the long-term course of illness.

Prescribing Trends in Bipolar Disorder: Cohort Study in the United Kingdom THIN Primary Care Database 1995–2009

ObjectivesTo determine changes in prescribing patterns in primary care of antipsychotic and mood stabiliser medication in a representative sample of patients with bipolar disorder in the United Kingdom over a fifteen year period and association with socio-demographic factors.MethodsWe identified 4700 patients in the Health Improvement Network (THIN) primary care database, who had received treatment for bipolar disorder between 1995 and 2009. The proportion of time for which each individual was prescribed a particular medication was studied, along with variation by sex, age and social depravation status (quintiles of Townsend scores). The number of drugs an individual was taking within a particular year was also examined.ResultsIn 1995, 40.6% of patients with bipolar disorder were prescribed a psychotropic medication at least twice. By 2009 this had increased to 78.5% of patients. Valproate registered with the greatest increase in use (22.7%) followed by olanzapine (15.7%) and quetiapine (9.9%). There were differences by age and sex; with young (18–30 year old) women having the biggest increase in proportion of time on medication. There were no differences by social deprivation status. By 2009, 34.2% of women of childbearing age were treated with valproate.ConclusionsLithium use overall remained relatively constant, whilst second generation antipsychotic and valproate use increased dramatically. Changes in prescribing practice preceded published trial evidence, especially with the use of second generation antipsychotics, perhaps with inferences being made from treatment of schizophrenia and use of first generation antipsychotics. Women of childbearing age were prescribed valproate frequently, against best advice.

The gradual vocal responses to human-provoked discomfort in farmed silver foxes

Vocal indicators of welfare have proven their use for many farmed and zoo animals and may be applied to farmed silver foxes as these animals display high vocal activity toward humans. Farmed silver foxes were selected mainly for fur, size, and litter sizes, but not for attitudes to people, so they are fearful of humans and have short-term welfare problems in their proximity. With a human approach test, we designed here the steady increase and decrease of fox-human distance and registered vocal responses of 25 farmed silver foxes. We analyzed the features of vocalizations produced by the foxes at different fox-human distances, assuming that changes in vocal responses reflect the degrees of human-related discomfort. For revealing the discomfort-related vocal traits in farmed silver foxes, we proposed and tested the algorithm of "joint calls," equally applicable for analysis of all calls independently on their structure, either tonal or noisy. We discuss that the increase in proportion of time spent vocalizing and the shift of call energy toward higher frequencies may be integral vocal characteristics of short-term welfare problems in farmed silver foxes and probably in other captive mammals.

Changes in surrogate outcomes can be translated into clinical outcomes using a Monte Carlo model

Objective To meaningfully interpret trials using surrogate outcomes, one must translate changes in the surrogate outcome to changes in the clinical outcome. Formulae to do this are uncommon because they require primary data from multiple randomized trials that measure both the surrogate and clinical outcome. Study Design and Setting We developed a model to translate changes in anticoagulation control (the surrogate outcome) into hemorrhagic and thromboembolic event rates (the clinical outcome). The model used Monte Carlo simulation and association measures between the surrogate and the clinical outcome from a meta-analysis. In randomized trials having interventions that improved anticoagulation control, we used the model to predict and statistically compare event rates between the study groups. Results Seven randomized trials found significantly improved anticoagulation control (mean increase in proportion of time in therapeutic range: 8.4%; range: 1.8–18%). These improvements in anticoagulation control translated to small decreases in hemorrhagic and thromboembolic events (mean: 0.66%/yr; range: 0.13–1.42%). These changes were never statistically significant. Conclusion Monte Carlo modeling can be used to translate surrogate outcomes into clinical outcomes. Statistically significant changes in anticoagulation control did not translate to significant differences in clinical outcomes. This methodology could be applied to other areas in medicine to assess surrogate outcomes.

DEVELOPMENT OF DIVING BY HARBOR SEAL PUPS IN TWO REGIONS OF ALASKA: USE OF THE WATER COLUMN

AbstractSatellite‐linked dive recorders were attached to 53 harbor seal pups in Prince William Sound (PWS) and at Tugidak Island, Alaska, during 1997–1999. We used generalized additive models and bootstrap techniques to describe pup diving behavior during their first year of life. Pups increased their ability to dive during the first 3–6 mo, as indicated by increases in proportion of time in the water (time wet) and maximum dive depth achieved by a pup each day (max‐depth) values. Time wet and/or max‐depth later decreased, suggesting a seasonal component to diving behavior. Monthly time wet varied from an overall minimum of 0.68 at tagging in July to a maximum of 0.89 in November. Pups spent half of their time wet swimming in water &lt;25 m deep, the shallowest 30% of the available water column. They spent only 5% of their time swimming in the deepest 30% of the available water column, at depths &gt;60–70 m. This strongly suggests they were not feeding on or near bottom during their first year. Average max‐depths and deepest actual dives were similar for PWS and Tugidak pups. PWS pups dove deeper sooner and spent less time wet than Tugidak pups during the first few months after tagging, probably as a result of regional bathymetric differences. Diving behavior and body condition suggest that food availability was not likely a major factor in the population decline in PWS during the period of this study.

A Component Analysis of the Room Manager Role

A component analysis of the room manager role (Porterfield et al., 1980) was performed in a series of four experiments. The subjects were one nursing staff and 13 severely and profoundly mentally handicapped young adults. The experiments took place in a hospital adult training unit. Five components (presence of toys in the room, providing a toy, replacing toys, prompting, and the full room manager role) were compared. Increases in the proportion of time on task were associated with the antecedents; praising had no effect. For residents with high Vineland Social Age regularly replacing toys was associated with the greatest increase in the proportion of time on task. For residents with low Vineland Social Age prompting was associated with the greatest increase in proportion of time on task. Implications for modification of the room manager role are considered and limitations to the present study discussed.