Sampling a branching tree

AbstractA Galton-Watson branching tree is sampled, yielding a derived vector process of family sizes. Exact and asymptotic distributions for this process are derived, rates of convergence given, and the probability of selecting different families is shown to converge rapidly to one. Consistent, asymptotically normal nonparametric estimates of the underlying offspring distribution are obtained and for power series distributions approximate MLE's are shown to be asymptotically normal and efficient

The Life and Times of Joseph Beuys

Program for the seventh annual RISD Cabaret held in the Waterman Building. Graphic design: Mark Snyder; program editor: Margaret Lewis; program photography: Marcin Gizycki.https://digitalcommons.risd.edu/liberalarts_cabaret_programs/1006/thumbnail.jp

Time courses of improvement and symptom remission in children treated with atomoxetine for attention-deficit/hyperactivity disorder: analysis of Canadian open-label studies

<p>Abstract</p> <p>Background</p> <p>The relatively short durations of the initial pivotal randomized placebo-controlled trials involving atomoxetine HCl for the treatment of attention-deficit/hyperactivity disorder (ADHD) provided limited insight into the time courses of ADHD core symptom responses to this nonstimulant, selective norepinephrine reuptake inhibitor. The aim of this analysis was to evaluate time courses of treatment responses or remission, as assessed by attainment of prespecified scores on the ADHD Rating Scale-IV-Parent Version: Investigator Administered and Scored (ADHDRS-IV-PI) and the Clinical Global Impressions-ADHD-Severity (CGI-ADHD-S) scales, during up to 1 year of atomoxetine treatment in children with ADHD.</p> <p>Methods</p> <p>Using pooled data from three Canadian open-label studies involving 338 children ages 6-11 years with ADHD who were treated with atomoxetine for 3, 6 and 12 months, and survival analysis methods for interval-censored data, we estimated the time to: 1) improvement and robust improvement defined by ≥25% and ≥40% reductions from baseline ADHDRS-IV-PI total scores, respectively; and 2) remission using two definitions: a final score of ADHDRS-IV-PI ≤18 or a final score of CGI-ADHD-S ≤2.</p> <p>Results</p> <p>The median time to improvement was 3.7 weeks (~1 month), but remission of symptoms did not occur until a median of 14.3 weeks (~3.5 months) using the most stringent CGI-ADHD-S threshold. Probabilities of robust improvement were 47% at or before 4 weeks of treatment; 76% at 12 weeks; 85% at 26 weeks; and 96% at 52 weeks. Probabilities of remission at these corresponding time points were 30%, 59%, 77%, and 85% (using the ADHDRS-IV scale) and 8%, 47%, 67%, and 75% (using the CGI-ADHD-S scale). The change from atomoxetine treatment month 5 to month 12 of -1.01 (1.03) was not statistically significant (<it>p </it>= .33).</p> <p>Conclusions</p> <p>Reductions in core ADHD symptoms during atomoxetine treatment are gradual. Although approximately one-half of study participants showed improvement at 1 month of atomoxetine treatment, remission criteria were not met until about 3 months. Understanding the time course of children's responses to atomoxetine treatment may inform clinical decision making and also influence the durations of trials comparing the effects of this medication with other ADHD treatments.</p> <p>Trial Registrations</p> <p>clinicaltrials.gov: <a href="http://www.clinicaltrials.gov/ct2/show/NCT00191633">NCT00191633</a>, <a href="http://www.clinicaltrials.gov/ct2/show/NCT00216918">NCT00216918</a>, <a href="http://www.clinicaltrials.gov/ct2/show/NCT00191880">NCT00191880</a>.</p

Consumption of a soy drink has no effect on cognitive function but may alleviate vasomotor symptoms in post-menopausal women; a randomised trial

Purpose: Cognitive decline is commonly reported during the menopausal transition, with memory and attention being particularly affected. The aim of this study was to investigate the effects of a commercially available soy drink on cognitive function and menopausal symptoms in post-menopausal women. Methods: 101 post-menopausal women, aged 44–63 years, were randomly assigned to consume a volume of soy drink providing a low (10 mg/day; control group), medium (35 mg/day), or high (60 mg/day) dose of isoflavones for 12 weeks. Cognitive function (spatial working memory, spatial span, pattern recognition memory, 5-choice reaction time, and match to sample visual search) was assessed using CANTAB pre- and post-the 12 week intervention. Menopausal symptoms were assessed using Greene’s Climacteric Scale. Results: No significant differences were observed between the groups for any of the cognitive function outcomes measured. Soy drink consumption had no effect on menopausal symptoms overall; however, when women were stratified according to the severity of vasomotor symptoms (VMS) at baseline, women with more severe symptoms at baseline in the medium group had a significant reduction (P = 0.001) in VMS post-intervention (mean change from baseline score: − 2.15 ± 1.73) in comparison to those with less severe VMS (mean change from baseline score: 0.06 ± 1.21). Conclusions: Soy drink consumption had no effect on cognitive function in post-menopausal women. Consumption of ~ 350 ml/day (35 mg IFs) for 12 weeks significantly reduced VMS in those with more severe symptoms at baseline. This finding is clinically relevant as soy drinks may provide an alternative, natural, treatment for alleviating VMS, highly prevalent among western women

Micropollutants in Water Recycling: A Case Study of N-Nitrosodimethylamine (NDMA) Exposure from Water versus Food

One of the most concerning xenobiotics currently under discussion by regulators and treatment experts is N-Nitrosodimethylamine (NDMA). NDMA is a carcinogen known to induce cancer in a variety of animals, causing DNA damage at low doses. Human exposure occurs through cigarettes, food, personal care products and drinking water, in addition to endogenous formation in the stomach. The daily tolerable limit for intake has been identified to be 4.0 - 9.3 ng/kg.day (Fitzgerald and Robinson 2007). Water at the WHO proposed guideline value of 100 ng/L would contribute about 2.9 ng/kg.day of this intake, while intake from food varies from 5.7 – 44.2 ng/kg.day. Smoking and workplace are additional exposure routes. This outlines that the exposure is often higher than tolerable limits. In the food and drinks industry this has in recent decades resulted in improved manufacturing processes. Awareness of NDMA in drinking water is a relatively recent issue. NDMA stems from precursors in raw water and can be generated during treatment. Generally removal of precursors is more achievable than the removal of NDMA itself. For example, the potent NDMA precursor dimethylamine is rapidly removed in biological pre-treatment, while many other precursor amines are more persistent. These precursor amines include some ion exchange resins and coagulants, used in water treatment processes, which have been shown to generate NDMA during chlorination. Ozonation has also been shown to produce NDMA in treatment. UV oxidation is the preferred method for removal of NDMA in water treatment, although reverse osmosis membranes are possible alternatives if effective retention can be achieved

31st Annual Meeting and Associated Programs of the Society for Immunotherapy of Cancer (SITC 2016) : part two

Background The immunological escape of tumors represents one of the main ob- stacles to the treatment of malignancies. The blockade of PD-1 or CTLA-4 receptors represented a milestone in the history of immunotherapy. However, immune checkpoint inhibitors seem to be effective in specific cohorts of patients. It has been proposed that their efficacy relies on the presence of an immunological response. Thus, we hypothesized that disruption of the PD-L1/PD-1 axis would synergize with our oncolytic vaccine platform PeptiCRAd. Methods We used murine B16OVA in vivo tumor models and flow cytometry analysis to investigate the immunological background. Results First, we found that high-burden B16OVA tumors were refractory to combination immunotherapy. However, with a more aggressive schedule, tumors with a lower burden were more susceptible to the combination of PeptiCRAd and PD-L1 blockade. The therapy signifi- cantly increased the median survival of mice (Fig. 7). Interestingly, the reduced growth of contralaterally injected B16F10 cells sug- gested the presence of a long lasting immunological memory also against non-targeted antigens. Concerning the functional state of tumor infiltrating lymphocytes (TILs), we found that all the immune therapies would enhance the percentage of activated (PD-1pos TIM- 3neg) T lymphocytes and reduce the amount of exhausted (PD-1pos TIM-3pos) cells compared to placebo. As expected, we found that PeptiCRAd monotherapy could increase the number of antigen spe- cific CD8+ T cells compared to other treatments. However, only the combination with PD-L1 blockade could significantly increase the ra- tio between activated and exhausted pentamer positive cells (p= 0.0058), suggesting that by disrupting the PD-1/PD-L1 axis we could decrease the amount of dysfunctional antigen specific T cells. We ob- served that the anatomical location deeply influenced the state of CD4+ and CD8+ T lymphocytes. In fact, TIM-3 expression was in- creased by 2 fold on TILs compared to splenic and lymphoid T cells. In the CD8+ compartment, the expression of PD-1 on the surface seemed to be restricted to the tumor micro-environment, while CD4 + T cells had a high expression of PD-1 also in lymphoid organs. Interestingly, we found that the levels of PD-1 were significantly higher on CD8+ T cells than on CD4+ T cells into the tumor micro- environment (p < 0.0001). Conclusions In conclusion, we demonstrated that the efficacy of immune check- point inhibitors might be strongly enhanced by their combination with cancer vaccines. PeptiCRAd was able to increase the number of antigen-specific T cells and PD-L1 blockade prevented their exhaus- tion, resulting in long-lasting immunological memory and increased median survival

What can or can't be estimated in branching and related processes?

AbstractEstimation of the underlying distribution is considered for the incompletely observed random walk and the incompletely observed Galton—Watson branching tree. Based on infrequent observation of a random walk, parameters not completely determined by the first few moments of the underlying distribution cannot be consistently estimated. A similar result is given for the branching tree when observations are sums of family sizes. When the offspring distribution belongs to the power series family MLE's are obtained from an approximate likelihood

What can or can't be estimated in branching and related processes?

Estimation of the underlying distribution is considered for the incompletely observed random walk and the incompletely observed Galton--Watson branching tree. Based on infrequent observation of a random walk, parameters not completely determined by the first few moments of the underlying distribution cannot be consistently estimated. A similar result is given for the branching tree when observations are sums of family sizes. When the offspring distribution belongs to the power series family MLE's are obtained from an approximate likelihood.random walk Galton-Watson branching tree consistent estimation