The PCsat Mission and Cubesat Design Notes

There are growing opportunities for Universities to gain educational access to Space. The Naval Academy has used the Department of Defense Space Test Program for its PCsat and Sapphire projects and the Stanford Cubesat program offers a unique opportunity to get numerous small student satellite payloads into space. As a spin-off of our PCsat project, we have investigated several off-the-shelf solutions to the Telemetry, Command and control portion of small satellites that can greatly simplify small satellite and CubeSat designs. This permits students to concentrate on the various payloads and other aspects of the project without starting from scratch with a comm. system. This simple comm. System based on AX.25 packet radio is being flown this summer in the Naval Academy’s Personal Communications Satellite (PCsat) which will demonstrate downlinks receivable on Hand Held Transceivers (HT’s) with only a whip antenna. Further these simple downlinks can be easily fed into the Internet for live worldwide distribution of data. These designs are all based on the amateur radio standard on-air AX.25 packet network protocol that is implemented in a number of off-the-shelf modems (called Terminal Node Controllers or TNC’s). The following paragraphs describe three such hardware devices and the remainder of this paper describes how TNC’s and the AX.25 protocol were used on PCsat

Microbial Metropolis: Understanding how legume pasture systems interact with soil microbial communities, and subsequent greenhouse gas emissions

Non-Peer ReviewedCattle producers may graze animals on mixed pastures of non-bloat legumes and grasses. This approach can increase dietary protein uptake, improve animal value, and reduce cattle methane emissions by decreasing pasture bloat. The introduction of legumes to a grass pasture can also affect greenhouse gas (GHG) fluxes from the soil by shifting the structure of the microbial communities responsible for nitrous oxide (N2O) emissions and methane consumption, and by altering mineralization rates and soil nutrient content. Two novel forage legume-grass mixes and a grass-alfalfa control were sampled throughout the 2017 and 2018 grazing seasons and analyzed for microbial community structure, nutrient cycling rates, as well as for N2O and methane GHG fluxes. Results suggest microbial community structure, rather than microbial abundance, as one factor regulating GHG emissions. Reduced phosphorous and nitrogen supply rates were key factors limiting microbial abundance, and communities experiencing these environmental stressors were correlated with reduced N2O fluxes. Increasing microbial abundance in response to substrate availability results in depletion of soil phosphorous and nitrogen. This in turn upregulates the carbon and nitrogen cycling activities of communities. Nitrogen and soil moisture content were correlated with increasing nitrous oxide emissions, suggesting that denitrification processes are the major contributor to pasture N2O emissions. In addition, decreasing moisture increased methane consumption, providing a partial sink for cattle-derived methane emissions. Sainfoin treatments had lower cumulative methane consumption when compared to cicer milkvetch and control treatments. Further analysis suggests that different interactions between environmental factors may be involved in shaping microbial communities within each legume treatment, and that local environmental conditions at each sampling point were more important than plant cover treatments in determining daily GHG fluxes. Understanding the microbial processes at play when considering net GHG emissions within a pasture system will contribute to the future sustainability of beef production systems

Availability of specialized healthcare facilities for deaf and hard of hearing individuals.

Context: To allow a medical consultation to proceed successfully, it is essential that physicians are aware of the linguistic and cultural backgrounds of deaf and hard of hearing individuals (DHH) and related communication aspects. Some specialised healthcare facilities have emerged to respond to the specific needs of people who are DHH. Objective: This study aims to provide insight into the various types of general healthcare facilities available for DHH individuals. By sharing and comparing experiences and results improvements can be made. Design, Data Sources and Study selection: A systematic review of the literature on specialised healthcare for DHH people was performed. The following databases were searched: PubMed, Web of Science, PsycINFO, Academic Search Premier, CINAHL and Embase. After independent extraction per article by two readers, fifteen articles were included in the systematic review. As it appeared that not all existing locations of facilities of which we were aware were described in the literature, we expanded the data collection with internet searches, specific literature searches and unstructured interviews. Results: Some countries have developed facilities to meet the needs DHH people Experts and patients’ groups report that the perceived quality of healthcare and health education in specialised healthcare settings is higher compared to regular healthcare settings. Two projects undertaken to improve the health related knowledge level of DHH people, proved to be effective. Conclusion: Some facilities or combinations of facilities are used in different countries to attempt to meet the needs of DHH patients. These facilities are rarely described in the scientific literature. Further development of specialised healthcare facilities for DHH patients, which should include high quality studies on their effectiveness, is imperative to comply with medical ethical standards and respect the human rights of DHH people

Catching Kordbolbok: From Frog Survey to Closing the Gap in Arnhem Land

This working paper introduces the first frog survey of the Arnhem Plateau, as far as we know, which was conducted by the Warddeken Indigenous Rangers and a western scientist employed by CAEPR. The survey methodology and outcomes are presented in conjunction with some comment on the socioeconomic benefits of such surveys in remote outstations of the Northern Territory. Thirteen native frog species known to western science were found, including one species that as far as we know is previously undescribed—as well as the exotic cane toad (Bufo marinus). This exercise highlighted the significant role already played by traditional owners in the management of Indigenous-owned Arnhem Land. A greater monitoring role—for example, through frog surveys—could be pursued given the right tools and training