61 research outputs found
Project Dawdler: a Proposal in Response to a Low Reynolds Number Station Keeping Mission
In direct response to Request for Proposals: Flight at very low Reynolds numbers - a station keeping mission, the members of Design Squad E present Project Dawdler: a remotely-piloted airplane supported by an independently controlled take-off cart. A brief introduction to Project Dawdler's overall mission and design, is given. The Dawdler is a remotely-piloted airplane designed to fly in an environmentally-controlled closed course at a Reynolds number of 10(exp 5) and at a cruise velocity of 25 ft/s. The two primary goals were to minimize the flight Reynolds number and to maximize the loiter time. With this in mind, the general design of the airplane was guided by the belief that a relatively light aircraft producing a fairly large amount of lift would be the best approach. For this reason the Dawdler utilizes a canard rather than a conventional tail for longitudinal control, primarily because the canard contributes a positive lift component. The Dawdler also has a single vertical tail mounted behind the wing for lateral stability, half of which is used as a rudder for yaw control. Due to the fact that the power required to take-off and climb to altitude is much greater than that required for cruise flight and simple turning maneuvers, it was decided that a take-off cart be used. Based on the current design, there are two unknowns which could possibly threaten the success of Project Dawdler. First, the effect of the fully-movable canard with its large appropriation of total lift on the performance of the plane, and secondly, the ability of the take-off procedure to go as planned are examined. These are questions which can only be answered by a prototype
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Research Review: In a rush to permanency: preventing adoption disruption
Since the late 1990s, US, UK and Canadian policy have increasingly focused on improving permanency outcomes for looked-after children. Although the ideal permanency outcome of reunification is attained for about half of the children entering out-of-home care, an increasing number of children are adopted each year. The vast majority of adoptions are stable and secure, but concerns about adoption disruption haunt child welfare workers when making this important permanency decision. Despite a variety of definitions employed in the literature, adoption disruption is a general term used to describe the failure or breakdown of an adoptive child's placement. Studies dating back to the 1970s have reported adoption disruption rates and the characteristics associated with those involved in such cases. This paper reviews available research, principally from the United States, and offers possible explanations for the wide range of reported disruption rates in the literature. After reviewing the research, practice implications for improving adoption outcomes and suggestions for future research are presented. © 2007 Blackwell Publishing Ltd
Multiorgan MRI findings after hospitalisation with COVID-19 in the UK (C-MORE): a prospective, multicentre, observational cohort study
Introduction:
The multiorgan impact of moderate to severe coronavirus infections in the post-acute phase is still poorly understood. We aimed to evaluate the excess burden of multiorgan abnormalities after hospitalisation with COVID-19, evaluate their determinants, and explore associations with patient-related outcome measures.
Methods:
In a prospective, UK-wide, multicentre MRI follow-up study (C-MORE), adults (aged ≥18 years) discharged from hospital following COVID-19 who were included in Tier 2 of the Post-hospitalisation COVID-19 study (PHOSP-COVID) and contemporary controls with no evidence of previous COVID-19 (SARS-CoV-2 nucleocapsid antibody negative) underwent multiorgan MRI (lungs, heart, brain, liver, and kidneys) with quantitative and qualitative assessment of images and clinical adjudication when relevant. Individuals with end-stage renal failure or contraindications to MRI were excluded. Participants also underwent detailed recording of symptoms, and physiological and biochemical tests. The primary outcome was the excess burden of multiorgan abnormalities (two or more organs) relative to controls, with further adjustments for potential confounders. The C-MORE study is ongoing and is registered with ClinicalTrials.gov, NCT04510025.
Findings:
Of 2710 participants in Tier 2 of PHOSP-COVID, 531 were recruited across 13 UK-wide C-MORE sites. After exclusions, 259 C-MORE patients (mean age 57 years [SD 12]; 158 [61%] male and 101 [39%] female) who were discharged from hospital with PCR-confirmed or clinically diagnosed COVID-19 between March 1, 2020, and Nov 1, 2021, and 52 non-COVID-19 controls from the community (mean age 49 years [SD 14]; 30 [58%] male and 22 [42%] female) were included in the analysis. Patients were assessed at a median of 5·0 months (IQR 4·2–6·3) after hospital discharge. Compared with non-COVID-19 controls, patients were older, living with more obesity, and had more comorbidities. Multiorgan abnormalities on MRI were more frequent in patients than in controls (157 [61%] of 259 vs 14 [27%] of 52; p<0·0001) and independently associated with COVID-19 status (odds ratio [OR] 2·9 [95% CI 1·5–5·8]; padjusted=0·0023) after adjusting for relevant confounders. Compared with controls, patients were more likely to have MRI evidence of lung abnormalities (p=0·0001; parenchymal abnormalities), brain abnormalities (p<0·0001; more white matter hyperintensities and regional brain volume reduction), and kidney abnormalities (p=0·014; lower medullary T1 and loss of corticomedullary differentiation), whereas cardiac and liver MRI abnormalities were similar between patients and controls. Patients with multiorgan abnormalities were older (difference in mean age 7 years [95% CI 4–10]; mean age of 59·8 years [SD 11·7] with multiorgan abnormalities vs mean age of 52·8 years [11·9] without multiorgan abnormalities; p<0·0001), more likely to have three or more comorbidities (OR 2·47 [1·32–4·82]; padjusted=0·0059), and more likely to have a more severe acute infection (acute CRP >5mg/L, OR 3·55 [1·23–11·88]; padjusted=0·025) than those without multiorgan abnormalities. Presence of lung MRI abnormalities was associated with a two-fold higher risk of chest tightness, and multiorgan MRI abnormalities were associated with severe and very severe persistent physical and mental health impairment (PHOSP-COVID symptom clusters) after hospitalisation.
Interpretation:
After hospitalisation for COVID-19, people are at risk of multiorgan abnormalities in the medium term. Our findings emphasise the need for proactive multidisciplinary care pathways, with the potential for imaging to guide surveillance frequency and therapeutic stratification
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Prevalence and predictors of HIV screening in invasive cervical cancer: a 10 year cohort study
BackgroundInvasive cervical carcinoma is associated with a human immunodeficiency virus (HIV) prevalence of >0.1%, and screening is recommended and cost-effective for cancer populations exceeding this threshold. HIV status is also prognostic for cancer-specific survival, but compliance with HIV screening is poor in the USA and abroad.ObjectivesThis study aims to describe HIV screening practices in a US comprehensive cancer center. To guide quality improvement, we identify characteristics which may predict compliance with screening.Study designWomen treated for invasive cervical cancer from January 2007 to December 2017 were identified by local cancer registry and billing data. We assessed age, race, ethnicity, insurance status, histology, stage, pregnancy, drug use, and HIV testing status. Univariate logistical regression was performed to assess predictors of completed HIV screening.ResultsOf 492 eligible women, the cumulative screening rate was 7.6%. Race, ethnicity, histology, and funding source were not predictive of screening. Every 5 year increase in age was associated with a lower chance of screening (OR 0.86, p=0.015), as was earlier stage at diagnosis (OR 0.43, p=0.017). Pregnancy during, or antecedent to, invasive cervical cancer diagnosis was significantly more predictive of screening compliance (OR 10.57, p=0.0007). Only 8/492 (1.6%) women in the cohort were active or former drug users, but within this group HIV screening was performed more frequently (OR 22.7, p<0.0001).ConclusionDespite US and international recommendations for HIV screening in AIDS-defining cancers, compliance remains low. In our centers, factors including earlier age, advanced stage, active pregnancy at diagnosis, and any drug use history were predictive of greater compliance with screening. These data will inform a tailored intervention to improve compliance with HIV screening in our population
Prevalence and predictors of HIV screening in invasive cervical cancer: a 10 year cohort study
BackgroundInvasive cervical carcinoma is associated with a human immunodeficiency virus (HIV) prevalence of >0.1%, and screening is recommended and cost-effective for cancer populations exceeding this threshold. HIV status is also prognostic for cancer-specific survival, but compliance with HIV screening is poor in the USA and abroad.ObjectivesThis study aims to describe HIV screening practices in a US comprehensive cancer center. To guide quality improvement, we identify characteristics which may predict compliance with screening.Study designWomen treated for invasive cervical cancer from January 2007 to December 2017 were identified by local cancer registry and billing data. We assessed age, race, ethnicity, insurance status, histology, stage, pregnancy, drug use, and HIV testing status. Univariate logistical regression was performed to assess predictors of completed HIV screening.ResultsOf 492 eligible women, the cumulative screening rate was 7.6%. Race, ethnicity, histology, and funding source were not predictive of screening. Every 5 year increase in age was associated with a lower chance of screening (OR 0.86, p=0.015), as was earlier stage at diagnosis (OR 0.43, p=0.017). Pregnancy during, or antecedent to, invasive cervical cancer diagnosis was significantly more predictive of screening compliance (OR 10.57, p=0.0007). Only 8/492 (1.6%) women in the cohort were active or former drug users, but within this group HIV screening was performed more frequently (OR 22.7, p<0.0001).ConclusionDespite US and international recommendations for HIV screening in AIDS-defining cancers, compliance remains low. In our centers, factors including earlier age, advanced stage, active pregnancy at diagnosis, and any drug use history were predictive of greater compliance with screening. These data will inform a tailored intervention to improve compliance with HIV screening in our population.</jats:sec
"Did You See What I Saw?" Gender Differences in Perceptions of Avenues to Prestige among Adolescents
Predicting family reunification, adoption, and subsidized guardianship among adolescents in foster care.
Strategies addressing barriers to clinical trial enrollment of underrepresented populations: A systematic review
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IRF2BPL Is Associated with Neurological Phenotypes
Interferon regulatory factor 2 binding protein-like (IRF2BPL) encodes a member of the IRF2BP family of transcriptional regulators. Currently the biological function of this gene is obscure, and the gene has not been associated with a Mendelian disease. Here we describe seven individuals who carry damaging heterozygous variants in IRF2BPL and are affected with neurological symptoms. Five individuals who carry IRF2BPL nonsense variants resulting in a premature stop codon display severe neurodevelopmental regression, hypotonia, progressive ataxia, seizures, and a lack of coordination. Two additional individuals, both with missense variants, display global developmental delay and seizures and a relatively milder phenotype than those with nonsense alleles. The IRF2BPL bioinformatics signature based on population genomics is consistent with a gene that is intolerant to variation. We show that the fruit-fly IRF2BPL ortholog, called pits (protein interacting with Ttk69 and Sin3A), is broadly detected, including in the nervous system. Complete loss of pits is lethal early in development, whereas partial knockdown with RNA interference in neurons leads to neurodegeneration, revealing a requirement for this gene in proper neuronal function and maintenance. The identified IRF2BPL nonsense variants behave as severe loss-of-function alleles in this model organism, and ectopic expression of the missense variants leads to a range of phenotypes. Taken together, our results show that IRF2BPL and pits are required in the nervous system in humans and flies, and their loss leads to a range of neurological phenotypes in both species
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De novo variants in RYBP are associated with a severe neurodevelopmental disorder and congenital anomalies
Purpose: Polycomb group proteins are key epigenetic transcriptional regulators. Multiple neurodevelopmental disorders are associated with pathogenic variants of the genes encoding Polycomb group proteins. RYBP is a core component of the noncanonical Polycomb Repressor Complex 1; however, its role in disease is unclear. Methods: Functional consequences of RYBP variants were assessed using in vitro cellular and in vivo Drosophila melanogaster studies. Results: We described 7 individuals with heterozygous de novo variants of RYBP and their clinical findings, including severe developmental delay, dysmorphisms, and multiple congenital anomalies. We showed that all single-nucleotide variants in RYBP localize to the N-terminal domain of the gene, which encodes the zinc-finger domain and ubiquitin-binding moiety. In vitro studies have demonstrated that the RYBP c.132C>G p.(Cys44Trp) variant causes reduced protein expression but does not affect the binding of YY1, RING1B, or ubiquitin. In vivo overexpression studies in Drosophila melanogaster showed a dramatic functional difference between human RYBP and its variant forms, affecting the C44 amino acid residue. DNA methylation studies suggested a possible episignature associated with RYBP-related disorder. Conclusion: Heterozygous de novo variants in RYBP are associated with an identifiable syndromic neurodevelopmental disorder with multiple congenital anomalies
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