14 research outputs found
Comparison of the Low-Cost Sun Sensors of the SOURCE and EIVE CubeSats
Sun sensors are commonly used attitude determination equipment which measure a spacecraft’s attitude relative to the sun. Multiple types of low-cost sun sensors were developed for the SOURCE and EIVE CubeSats. The SOURCE sun sensors consist of single photodiodes which are placed in a one-sensor-per-face as well as a pyramid arrangement. EIVE employs digital vector sun sensors based on quad-pin photodiodes. The SOURCE sun sensors in the one-sensor-per-face arrangement archive an accuracy of \u3c10° while the pyramid arrangement accomplishes an accuracy of \u3c7.5° without and \u3c5° with calibration. EIVE’s vector sun sensors offer an raw accuracy of 3°±5°. Multiple calibration approaches are presented with the best results leading to an accuracy of 0.7±3°. A direct comparison between the SOURCE and EIVE sensor types and configurations can be drawn since the same test bench was used to measure all sensors. The objective of this paper is to present and compare the different sun sensor concepts and their results
Finger creases lend a hand in Kabuki syndrome.
International audienceKabuki syndrome (KS) is a rare syndrome associating malformations with intellectual deficiency and numerous visceral, orthopedic, endocrinological, immune and autoimmune complications. The early establishment of a diagnostic of KS leads to better care of the patients and therefore prevents complications such as perception deafness, severe complications of auto-immune diseases or obesity. However, the diagnosis of KS remains difficult because based on the appreciation of facial features combined with other highly variable features. We describe a novel sign, namely the attenuation and/or congenital absence of the IPD crease of the third and fourth fingers associated with limitation of flexion of the corresponding joints, which seems to be specific of KS and could help the clinician to diagnose KS
Commissioning of the OPG1 plasma wind tunnel
This work presents the commissioning of the new Osney Plasma Generator 1
(OPG1) plasma wind tunnel at the University of Oxford. The OPG1 facility is equipped
with a thermal arc-jet plasma generator to supply high-enthalpy flows, replicating atmospheric re-entry environments. The small-scale and low operating cost of the arc-jet make
it ideal for preliminary screening of material samples, testing new plasma diagnostics, and
utilising it as a model pre-heating device. The paper outlines an overview of the facility
and summarises the experimental results obtained during the facility commissioning,
particularly regarding flow condition characterisation
Development of small scale arc-jet facility OPG1
A small-scale thermal arc-jet facility based on a 21.5 kW tungsten inert gas welding power supply has been developed. The design and simulations are presented here. The plasma generator is situated inside a vacuum vessel forming an Argon plasma with a mass flow rate of approximately 0.2 g/s. The vessel is evacuated by a series of pumps providing sufficient suction to keep the vessel below 125 Pa during continuous operation. The system is designed with regards to heat transfer and vacuum performance with the goal of keeping component temperatures pressures below critical values to prevent material failure and enable adequate vacuum. The thermal design of the plasma generator includes a water cooling circuit which keeps the copper anode below melting temperatures. A viscous reacting 2D axisymmetric simulation is carried out using Eilmer4 simulating the nozzle flow including the stagnation chamber and the free jet impinging onto a 40mm diameter sphere-cone model. The simulations predict a maximum heat flux on the model surface of approximately 800 kW/m2 when a plasma total temperature of 7400 K is assumed
Lessons Learned From a Food Environment Intervention Study: Recruitment and Retention of Participants in Disadvantaged Urban Inner-City Neighborhoods
Identifying superusers of health services with mental health and addiction problems: Putting the Canadian Institutes of Health Research Strategy for Patient Oriented Research into action
ABSTRACT
Objective
We were funded by Canadian Institutes of Health Research Strategy for Patient Oriented Research (CIHR-SPOR) to use administrative data to identify people with mental health and/or addiction (MHA) problems, and determine characteristics that lead to them becoming a superuser of health services. The aim of the CIHR-SPOR is to ensure that research improves healthcare systems and practices. Their approach is to fundamentally change the ivory tower nature of research to make it more inclusive, user friendly, and timely. An essential component of the CIHR-SPOR is engaging patients as partners at all stages of the research. In this presentation we will describe the challenges, successes, and failures of engaging patients as part of the research team.
Approach
In Saskatchewan, Canada, we engaged with community programs to determine the ‘on-the-ground’ reality of people living with MHA problems. Our discussions revealed that First Nations and Métis People are highly overrepresented in the MHA patient population. For example, they comprise 15% of the Saskatchewan population yet 70% of patients receiving treatment at a local methadone clinic. For this reason, we are focusing our efforts on engaging with this specific patient population.
Results
We encountered a number of barriers to finding patient advisors. First, patient advisors available through institutional programs are not representative of our target population, being more affluent, well-educated, and Caucasian. There are currently no formal avenues to identify and invite members of the target population to join the research team and so we are using personal connections and team building to identify patients advisors. Second, complicated institutional policies on reimbursement for patient advisors impede participation by low income individuals. Third, we are concerned the socioeconomic disparities common in this vulnerable population may impede their full and honest participation as a patient advisor.
Conclusions
Patients and their family members are invaluable members of the research team. However, a power differential often exists between team members and patients due to socioeconomic differences, including race and education. Stigmatized health conditions such as MHA problems can exacerbate the feelings of a power differential. All of these things can prevent genuine involvement by patients. The most important step in successfully involving these untraditional team members is building trust through unconditional acceptance and respect for each individual’s lived experience. Building trust takes time and so patient engagement cannot be expected to follow a rigid schedule
Identifying superusers of health services with mental health and addiction problems
ABSTRACT
Objective
The objective of this research is to identify people with mental health and/or addiction (MHA) problems and determine characteristics that led to them becoming a superuser of health services (i.e., the most expensive 10% of all health service users).
Approach
In Saskatchewan, Canada, we used hospital and physician administrative data spanning 2005 to 2014 to identify the MHA cohort. We will calculate total health care costs for each individual and assign them to one of three groups: low cost users (<50th percentile), moderate cost users (50-<90th percentile), and superusers (90th percentile and above). For each group, we will describe sociodemographic characteristics, disease characteristics, and use of health services, and describe their trajectory towards becoming a superuser. Predictors of becoming a superuser will be identified. A novel aspect of this research is the inclusion of sociobehavioural risk factors by linking 4 population and public health administrative datasets obtained from the Saskatoon Health Region to the provincial administrative health services data. Sociobehavioral factors are widely accepted as strongly influencing health. Each database was selected because it captures data on a sociobehavioral factor. The Oral Health Database contains data on early childhood development, including early childhood tooth decay, dental health status, and tobacco use in elementary school-aged children. The Integrated Public Health Information System contains data on self-reported ethnicity, the occurrence of an infectious notifiable disease, and behavioural and social risk factors for the notifiable disease. The Sexually Transmitted Infection (STI) Clinic Data contains data on exposure to and contraction of STIs, as well as referrals given for mental health and/or addiction services. Finally, the Street Outreach Program provides services to individuals living a high-risk lifestyle on the street. Their database contains information on self-reported ethnicity, hypodermic needle exchange, and homelessness.
Results
In a province of approximately 1.1 million people, we identified 417,724 people as having at least 1 MHA diagnosis, of which two-thirds were depression and/or anxiety. Substance abuse was found in 9.4%, and schizotypal and psychotic disorders were found in 7.9%, of the MHA cohort,
Conclusion
Individuals with severe MHA problems account for a disproportionate amount of health care costs. Identifying predictors of becoming an MHA superuser may afford an opportunity to intervene, possibly years in the future, to prevent a person from becoming a superuser. If true, this has significant implications for health care costs, wait times to access health services, and quality of life for this vulnerable population
Parental attitudes and behaviours concerning helmet use in childhood activities: Rural focus group interviews
Spectrum of steroid-resistant and congenital nephrotic syndrome in children: The podoNet registry cohort
Background and objectives Steroid-resistant nephrotic syndrome is a rare kidney disease involving either immune-mediated or genetic alterations of podocyte structure and function. The rare nature, heterogeneity, and slow evolution of the disorder are major obstacles to systematic genotype-phenotype, intervention, and outcome studies, hampering the development of evidence-based diagnostic and therapeutic concepts. To overcome these limitations, the PodoNet Consortium has created an international registry for congenital nephrotic syndrome and childhood-onset steroid-resistant nephrotic syndrome. Design, setting, participants, & measurements Since August of 2009, clinical, biochemical, genetic, and histopathologic information was collected both retrospectively and prospectively from 1655 patients with childhood-onset steroid-resistant nephrotic syndrome, congenital nephrotic syndrome, or persistent subnephrotic proteinuria of likely genetic origin at 67 centers in 21 countries through an online portal. Results Steroid-resistant nephrotic syndrome manifested in the first 5 years of life in 64% of the patients. Congenital nephrotic syndrome accounted for 6% of all patients. Extrarenal abnormalities were reported in 17% of patients. The most common histopathologic diagnoses were FSGS (56%), minimal change nephropathy (21%), and mesangioproliferative GN (12%). Mutation screening was performed in 1174 patients, and a genetic disease cause was identified in 23.6% of the screened patients. Among 14 genes with reported mutations, abnormalities in NPHS2 (n=138), WT1 (n=48), and NPHS1 (n=41) were most commonly identified. The proportion of patients with a genetic disease cause decreased with increasing manifestation age: from 66% in congenital nephrotic syndrome to 15%-16% in schoolchildren and adolescents. Among various intensified immunosuppressive therapy protocols, calcineurin inhibitors and rituximab yielded consistently high response rates, with 40%-45% of patients achieving complete remission. Confirmation of a genetic diagnosis but not the histopathologic disease type was strongly predictive of intensified immunosuppressive therapy responsiveness. Post-transplant disease recurrence was noted in 25.8% of patients without compared with 4.5% (n=4) of patients with a genetic diagnosis. Conclusions The PodoNet cohort may serve as a source of reference for future clinical and genetic research in this rare but significant kidney disease. © 2015 by the American Society of Nephrology
Diagnostic strategy in segmentation defect of the vertebrae: a retrospective study of 73 patients
International audienceBackground Segmentation defects of the vertebrae (SDV) are non-specific features found in various syndromes. The molecular bases of SDV are not fully elucidated due to the wide range of phenotypes and classification issues. The genes involved are in the Notch signalling pathway, which is a key system in somitogenesis. Here we report on mutations identified in a diagnosis cohort of SDV. We focused on spondylocostal dysostosis (SCD) and the phenotype of these patients in order to establish a diagnostic strategy when confronted with SDV.Patients and methods We used DNA samples from a cohort of 73 patients and performed targeted sequencing of the five known SCD-causing genes (DLL3, MESP2, LFNG, HES7 and TBX6) in the first 48 patients and whole-exome sequencing (WES) in 28 relevant patients.Results Ten diagnoses, including four biallelic variants in TBX6, two biallelic variants in LFNG and DLL3, and one in MESP2 and HES7, were made with the gene panel, and two diagnoses, including biallelic variants in FLNB and one variant in MEOX1, were made by WES. The diagnostic yield of the gene panel was 10/73 (13.7%) in the global cohort but 8/10 (80%) in the subgroup meeting the SCD criteria; the diagnostic yield of WES was 2/28 (8%).Conclusion After negative array CGH, targeted sequencing of the five known SCD genes should only be performed in patients who meet the diagnostic criteria of SCD. The low proportion of candidate genes identified by WES in our cohort suggests the need to consider more complex genetic architectures in cases of SDV