Seeing the Wood for the Trees: A Critical Evaluation of Methods to Estimate the Parameters of Stochastic Differential Equations. Working paper #2

Maximum-likelihood estimates of the parameters of stochastic differential equations are consistent and asymptotically efficient, but unfortunately difficult to obtain if a closed form expression for the transitional probability density function of the process is not available. As a result, a large number of competing estimation procedures have been proposed. This paper provides a critical evaluation of the various estimation techniques. Special attention is given to the ease of implementation and comparative performance of the procedures when estimating the parameters of the Cox-Ingersoll-Ross and Ornstein-Uhlenbeck equations respectively.stochastic differential equations, parameter estimation, maximum likelihood, simulation, moments

Measuring Iron Bioavailability in Peas via Cell Culture Assay, Chicken (Gallus gallus) Feeding Study, and Athlete Trials

Non-Peer ReviewedField pea is a valuable crop for delivery of high protein content, slowly digested carbohydrates, fiber, and a high density of vitamins and minerals, including iron. High iron levels are of particular importance in human diets, as anemia is an ongoing challenge for many individuals. Iron levels in seeds at harvest are mitigated by nutrient levels in the soil and crop genetics. However, although high iron levels may be measured in some pea varieties, there may be limited absorption during digestion due to presence of the naturally occurring plant molecule phytate, which chelates with iron, zinc, and other cations. The Warkentin team, at the University of Saskatchewan, have bred agronomically viable pea lines that are low in phytate. Collaborating with scientists at Cornell University, Ithaca, NY, these lines were tested for iron bioavailability by the Caco-2 cell culture assay and a chicken feeding study. This talk will summarize the research to date and share plans for upcoming human trials involving endurance-trained women and Paralympic athletes, two groups particularly prone to anemia. Link to Video Presentation: https://youtu.be/Y__lg9K3a3

Health-related quality of life and its determinants during and after treatment for paediatric acute lymphoblastic leukaemia:a national, prospective, longitudinal study in the Netherlands

OBJECTIVES: Health-related quality of life (HRQoL) is impaired in paediatric patients with acute lymphoblastic leukaemia (ALL). Over the past decades, ALL treatment has successfully been adjusted to the risk of relapse, which is now reflected by the stratification of patients into three risk groups who receive treatment of differing intensities. This study is the first to evaluate the longitudinal course of HRQoL in light of these adjustments and identify determinants of HRQoL. DESIGN: Two prospective, national cohort studies (add-on studies within the two most recent treatment protocols for children with ALL (ALL-10 and ALL-11)). SETTING: Dutch paediatric oncology hospitals between October 2006 and October 2009 (ALL-10) and between August 2013 and July 2017 (ALL-11).PARTICIPANTS: Patients with ALL (2-18 years) are treated according to the ALL-10 or ALL-11 treatment protocol. Patients treated according to the ALL-10 protocol only completed a cancer-specific QoL measure and patients treated according to the ALL-11 protocol completed both a cancer-specific and generic QoL measure (see below). OUTCOME MEASURES: HRQoL, assessed with parent-proxy questionnaires (PedsQL Generic and Cancer module) within the first 5 months (T0), at 1 year (T1), 2 years (T2) and 3 years (T3) after diagnosis. The proportion of patients with clinically relevant generic HRQoL impairment was compared with healthy norm values. Multivariable mixed model analyses were used to evaluate the development of HRQoL over time and its medical and sociodemographic determinants (collected on enrolment). RESULTS: Of the ALL-10 cohort, 132 families participated and of the ALL-11 cohort, 136 families participated (268 total). Thus, cancer-specific HRQoL assessments were available for 268 patients (median age 5.3 years (IQR 6.15), 56.0% boys, 69.0% medium-risk ALL), and generic HRQoL assessments for 136 patients (median age 4.8 years (IQR 6.13), 60.3% boys, 75.0% medium-risk ALL). Generic HRQoL improved between timepoints T0 and T3 (total score B 16.1, 95% CI 12.2 to 20.1, p&lt;0.001), but did not restore to normal 1 year after the end of treatment: 28.0% of children remained impaired compared with 16% in the general population (p=0.003). Cancer-specific HRQoL generally improved from T0 to T2 (Pain B 11.3, 95% CI 7.1 to 15.5; Nausea B 11.7, 8.4 to 15.1; Procedural Anxiety B 19.1, 14.8 to 23.4; Treatment Anxiety B 12.8, 9.5 to 16.0; Worry B 3.5, 0.6 to 6.3; Communication B 8.5, 5.0 to 11.9; all p&lt;0.001 except for Worry (p=0.02)), while Physical Appearance and Cognitive Functioning remained stable. Higher treatment intensity and experiencing pain or simultaneous chronic illness were associated with lower HRQoL over time for multiple subscales. CONCLUSIONS: HRQoL impairment is prevalent during and after ALL treatment. Patients with standard-risk ALL and reduced treatment intensity have better HRQoL than patients in higher risk groups. Systematic monitoring of HRQoL is of utmost importance in order to provide timely psychosocial interventions and supportive care.</p

Parental functioning during maintenance treatment for childhood acute lymphoblastic leukemia: Effects of treatment intensity and dexamethasone pulses

Background: During maintenance treatment, Dutch pediatric patients with medium-risk (MR) acute lymphoblastic leukemia (ALL) receive intravenous chemotherapy and cyclic dexamethasone. Dexamethasone affects child's sleep and behavior. Standard-risk (SR) patients only receive oral chemotherapy, without dexamethasone. Effects of stratified therapy on parents are not well known. This study compares parental sleep, distress and quality of life (QoL) with the general population, between MR and SR groups, and on- and off-dexamethasone (MR group). Procedure: One year after diagnosis, parents of MR patients completed the Medical Outcomes Study (MOS) sleep, distress thermometer for parents and Short Form-12 (SF-12) twice; once on-dexamethasone and once off-dexamethasone. SR parents completed one measurement. Sleep problems, distress and QoL scores (off-dexamethasone) were compared to reference values and between MR and SR. Score differences on- and off-dexamethasone were assessed by multilevel regression analysis. Results: Parents (80% mothers) of 121 patients (57% males; 75% MR, 25% SR) completed 191 measurements. Compared to reference values, parents reported more sleep disturbances, higher distress, and lower mental QoL. Additionally, MR parents reported clinical distress (score ≥ 4), whereas SR parents (on average) did not (mean 4.8 ± 2.4 vs 3.5 ± 2.4, P =.02). Within the MR group, outcomes did not significantly differ on- and off-dexamethasone. Conclusions: Parents of ALL patients report sleep problems, high distress, and QoL impairment. Within the MR group, parental functioning did not differ on- and off-dexamethasone. However, MR parents reported clinical distress more often than SR parents, possibly reflecting differences in prognostic estimates and treatment burden. This perhaps includes the overall strain of cyclic dexamethasone. This study highlights the need for psychosocial support throughout treatment, regardless of risk stratification

Recovered memories, satanic abuse, Dissociative Identity Disorder and false memories in the UK: a survey of Clinical Psychologists and Hypnotherapists

An online survey was conducted to examine psychological therapists’ experiences of, and beliefs about, cases of recovered memory, satanic / ritualistic abuse, Multiple Personality Disorder / Dissociative Identity Disorder, and false memory. Chartered Clinical Psychologists (n=183) and Hypnotherapists (n=119) responded. In terms of their experiences, Chartered Clinical Psychologists reported seeing more cases of satanic / ritualistic abuse compared to Hypnotherapists who, in turn, reported encountering more cases of childhood sexual abuse recovered for the first time in therapy, and more cases of suspected false memory. Chartered Clinical Psychologists were more likely to rate the essential accuracy of reports of satanic / ritualistic abuse as higher than Hypnotherapists. Belief in the accuracy of satanic / ritualistic abuse and Multiple Personality Disorder / Dissociative Identity Disorder reports correlated negatively with the belief that false memories were possible

Perspectives in visual imaging for marine biology and ecology: from acquisition to understanding

Durden J, Schoening T, Althaus F, et al. Perspectives in Visual Imaging for Marine Biology and Ecology: From Acquisition to Understanding. In: Hughes RN, Hughes DJ, Smith IP, Dale AC, eds. Oceanography and Marine Biology: An Annual Review. 54. Boca Raton: CRC Press; 2016: 1-72

Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study

A41 Use of SMS texts for facilitating access to online alcohol interventions: a feasibility study In: Addiction Science & Clinical Practice 2017, 12(Suppl 1): A4