SatTherm: A Thermal Analysis and Design Tool for Small Spacecraft

Small spacecraft have become an attractive alternative for a significant class of space missions. They have the potential to provide valuable science data with shorter development times and at a reduced cost over traditional multi-instrument spacecraft. However, many of the legacy tools used for spacecraft design and analysis have considerable cost and complexity that are not suited to small spacecraft and their associated short development cycles. SatTherm is an alternative thermal analysis tool specifically developed for small spacecraft as a collaborative effort between the Mission Design Center at NASA Ames and San Jose State University. It is intended to be available to the small spacecraft community. SatTherm consists of an easy to use, Microsoft Excel user-interface coupled to a suite of Matlab routines that determine the time dependant temperature solution for spacecraft components. This paper presents a comparison that includes the accuracy of results and the ease of use between SatTherm and the commercially available Thermal Desktop software by Cullimore & Ring Technologies. A benchmark case of a model of the small spacecraft, PharmaSat, is presented. The time-dependant temperatures predicted by the SatTherm model agree with those predicted by the Thermal Desktop model within 4 Degrees Celsius or less. Both models are also validated by the flight data, recorded after the spacecraft was launched in May 2009 . This demonstrates that SatTherm can be a useful tool for the early design stage of a small spacecraft

Human papillomavirus vaccination practices and perceptions among Ghanaian Healthcare Providers: A qualitative study based on multi-theory model.

BackgroundHealthcare providers' (HCPs) recommendations for the Human Papillomavirus (HPV) vaccine are likely to increase the vaccination uptake. However, little is known about Ghanaian HCPs' general practices regarding HPV vaccination. We used Multi-Theory Model (MTM) constructs (i.e. participatory dialogue, behavioral confidence, environment, social and emotional transformation) to examine Ghanaian HCPs' attitudes towards HPV vaccination and their vaccination recommendation practices.MethodsWe conducted three, 60-minute focus group discussions (FGDs) with HCP in the second-largest government hospital in Ghana. Sixteen semi-structured open-ended questions based on MTM constructs were used to guide the FGDs. We explored HCPs' general knowledge about HPV, vaccination recommendation behavior, physical environment, and socio-cultural factors associated with the HPV vaccination. Data from the FGDs were transcribed and thematically coded using NVivo software.ResultsThe sample of (n = 29) HCPs consisting of males (n = 15) and females (n = 14) between the ages of 29 and 42 years participated in the FGDs. Our analyses showed that HCPs (a) rarely offered HPV vaccination recommendations, (b) showed varied understanding about who should be vaccinated regarding age eligibility, gender, and infection status. Perceived barriers to HPV vaccination include (a) low urgency for vaccination education due to competing priorities such as malaria and HIV/AIDS; (b) lack of data on HPV vaccination; (c) lack of awareness about the vaccine safety and efficacy; (c) lack of HPV vaccine accessibility and (d) stigma, misconceptions and religious objections. HCPs expressed that their motivation for counseling their clients about HPV vaccination would be increased by having more knowledge about the vaccine's efficacy and safety, and the involvement of the parents, chiefs, churches, and opinion leaders in the vaccination programs.ConclusionThe study's findings underscore the need for a comprehensive HPV vaccination education for HCPs in Ghana. Future HPV vaccination education programs should include information about the efficacy of the vaccine and effective vaccination messages to help mitigate HPV vaccine-related stigma