Resource Prospector: Evaluating the ISRU Potential of the Lunar Poles

Resource Prospector (RP) is a lunar volatiles prospecting mission being developed for potential flight in CY2021-2022. The mission includes a rover-borne payload that (1) can locate surface and near-subsurface volatiles, (2) excavate and analyze samples of the volatile-bearing regolith, and (3) demonstrate the form, extractability and usefulness of the materials. The primary mission goal for RP is to evaluate the In-Situ Resource Utilization (ISRU) potential of the lunar poles

Robotic Lunar Landers for Science and Exploration

NASA Marshall Space Flight Center (MSFC) and The Johns Hopkins University Applied Physics Laboratory (APL) have been conducting mission studies and performing risk reduction activities for NASA s robotic lunar lander flight projects. This paper describes some of the lunar lander concepts derived from these studies conducted by the MSFC/APL Robotic Lunar Lander Development Project team. In addition, the results to date of the lunar lander development risk reduction efforts including high pressure propulsion system testing, structure and mechanism development and testing, long cycle time battery testing and combined GN&C and avionics testing will be addressed. The most visible elements of the risk reduction program are two autonomous lander flight test vehicles: a compressed air system with limited flight durations and a second version using hydrogen peroxide propellant to achieve significantly longer flight times and the ability to more fully exercise flight sensors and algorithms

Experimental evidence of parametric decay processes in the variable specific impulse magnetoplasma rocket (VASIMR) helicon plasma source

Decay waves have been observed in the megahertz range in the helium plasma generated by the variable specific impulse magnetoplasma rocket magnetoplasma thruster. They are measured using one of the tips of a triple probe connected to a 50 Ω input of a spectrum analyzer via a dc block (a small capacitor). The maximum amplitude of all waves is in the center of the plasma and does not appear correlated to the radial electron density or temperature profiles. The waves seem to be generated close to the helicon antenna that was 91 cm “upstream” from the measuring Langmuir probe. A possible explanation is parametric decay of the large amplitude helicon wave that also generates the plasma.This project was proudly supported by the International Science Linkages programme established under the Australian Government’s innovation statement Backing Australia’s Ability

Toothache and associated factors in Brazilian adults: a cross-sectional population-based study

Extent: 8p.Background: Toothache is a dental public health problem and one of the predictors of dental attendance and it is strongly associated with the life quality of individuals. In spite of this, there are few population-based epidemiological studies on this theme. Objective: To estimate the prevalence of toothache and associated factors in adults of Lages, Southern Brazil. Methods: A cross-sectional population-based study was carried out in a sample of 2,022 adults aged 20 to 59 years living in the urban area of a medium sized city in Southern Brazil. A questionnaire including socioeconomic, demographic, smoking, alcohol, and use of dental service variables was applied at adults household. Toothache occurred six months previous of the interview was considered the outcome. Poisson regression analyses were performed following a theoretical hierarchical framework. All analysis was adjusted by the sample design effect. Results: The response rate was 98.6%. The prevalence of toothache was 18.0% (95% CI 16.0; 20.1). The following variables were associated with toothache after adjustment: female (PR = 1.3 95% CI 1.3; 2.0), black skin colour vs. whites (PR = 1.5 95% CI 1.1, 1.9), low per capita income (PR = 1.7 95% CI 1.2, 2.3), smokers (PR = 1.5 95% CI 1.2, 1.9) and those who reported alcohol problems (PR = 1.4 95% CI 1.1; 1.9). To be 40 years of age (PR = 0.5 95% CI 0.4, 0.7) and use dental service in the last year (RR = 0.5 95% CI 0.4, 0.6) were protective factors for toothache. Conclusion: The prevalence of toothache in adults of Lages can be considered a major problem of dental public health.Mirian Kuhnen, Marco A Peres, Anelise V Masiero and Karen G Pere

Case-case-control study on factors associated with vanB vancomycin-resistant and vancomycin-susceptible enterococcal bacteraemia

BACKGROUND: Enterococci are a major cause of healthcare-associated infection. In Australia, vanB vancomycin-resistant enterococci (VRE) is the predominant genotype. There are limited data on the factors linked to vanB VRE bacteraemia. This study aimed to identify factors associated with vanB VRE bacteraemia, and compare them with those for vancomycin-susceptible enterococci (VSE) bacteraemia. METHODS: A case-case-control study was performed in two tertiary public hospitals in Victoria, Australia. VRE and VSE bacteraemia cases were compared with controls without evidence of enterococcal bacteraemia, but may have had infections due to other pathogens. RESULTS: All VRE isolates had vanB genotype. Factors associated with vanB VRE bacteraemia were urinary catheter use within the last 30 days (OR 2.86, 95% CI 1.09-7.53), an increase in duration of metronidazole therapy (OR 1.65, 95% CI 1.17-2.33), and a higher Chronic Disease Score specific for VRE (OR 1.70, 95% CI 1.05-2.77). Factors linked to VSE bacteraemia were a history of gastrointestinal disease (OR 2.29, 95% CI 1.05-4.99) and an increase in duration of metronidazole therapy (OR 1.23, 95% CI 1.02-1.48). Admission into the haematology/oncology unit was associated with lower odds of VSE bacteraemia (OR 0.08, 95% CI 0.01-0.74). CONCLUSIONS: This is the largest case-case-control study involving vanB VRE bacteraemia. Factors associated with the development of vanB VRE bacteraemia were different to those of VSE bacteraemia

Long-term outcome of chronic dialysis in children

As the prevalence of children on renal replacement therapy (RRT) increases world wide and such therapy comprises at least 2% of any national dialysis or transplant programme, it is essential that paediatric nephrologists are able to advise families on the possible outcome for their child on dialysis. Most children start dialysis with the expectation that successful renal transplantation is an achievable goal and will provide the best survival and quality of life. However, some will require long-term dialysis or may return intermittently to dialysis during the course of their chronic kidney disease (CKD). This article reviews the available outcome data for children on chronic dialysis as well as extrapolating data from the larger adult dialysis experience to inform our paediatric practice. The multiple factors that may influence outcome, and, particularly, those that can potentially be modified, are discussed

Genetic polymorphisms of the RAS-cytokine pathway and chronic kidney disease

Chronic kidney disease (CKD) in children is irreversible. It is associated with renal failure progression and atherosclerotic cardiovascular (CV) abnormalities. Nearly 60% of children with CKD are affected since birth with congenital or inherited kidney disorders. Preliminary evidence primarily from adult CKD studies indicates common genetic risk factors for CKD and atherosclerotic CV disease. Although multiple physiologic pathways share common genes for CKD and CV disease, substantial evidence supports our attention to the renin angiotensin system (RAS) and the interlinked inflammatory cascade because they modulate the progressions of renal and CV disease. Gene polymorphisms in the RAS-cytokine pathway, through altered gene expression of inflammatory cytokines, are potential factors that modulate the rate of CKD progression and CV abnormalities in patients with CKD. For studying such hypotheses, the cooperative efforts among scientific groups and the availability of robust and affordable technologies to genotype thousands of single nucleotide polymorphisms (SNPs) across the genome make genome-wide association studies an attractive paradigm for studying polygenic diseases such as CKD. Although attractive, such studies should be interpreted carefully, with a fundamental understanding of their potential weaknesses. Nevertheless, whole-genome association studies for diabetic nephropathy and future studies pertaining to other types of CKD will offer further insight for the development of targeted interventions to treat CKD and associated atherosclerotic CV abnormalities in the pediatric CKD population