Aquatic invertebrate protein sources for long-duration space travel.

During the summer of 2020, NASA returned to launching astronauts to the International Space Station (ISS) from American soil. By 2024, NASA's mission is to return to the Moon, and by 2028 create a sustainable presence. Long duration missions come with obstacles, especially when trying to create a sustainable environment in a location where "living off the land" is impossible. Some resources on the Moon can be recovered or resupplied; however, many resources such as those needed for sustaining life must be recycled or grown to support humans. To achieve sustainability, food and water must be grown and recycled using elements found within the habitat. NASA's current work focuses on food resupply and growing plants as supplemental nutrient content. This paper examines the possibility for using aquaculture systems to purify water while growing nutrient-rich species as food sources, which aquatic food sources would be ideal for a habitat environment, and which species might provide an ideal test case for future studies aboard ISS. The aquatic species should be rapidly grown with high protein content and low launch mass requirements. Although there are numerous challenges and unknown technology gaps for maintaining aquaculture systems in reduced gravity environments, the benefit of employing such systems would be of great advantage towards creating a sustainable presence beyond Earth's orbit for sustainable aquaculture.

Low concentration of zeolite to enhance microalgal growth and ammonium removal efficiency in a membrane photobioreactor.

The aim of this work was to study the growth and nutrient removal efficiency of a mixed microalgal culture with and without the addition of low concentrations (0.5, 1, and 5 g L-1 of total liquid volume in the reactor) of natural zeolite. A control test in which only zeolite was added into a similar membrane photobioreactor was also conducted. The addition of 0.5 g L-1 zeolite to a continuously-fed membrane photobioreactor increased the microalgal biomass concentration from 0.50 to 0.90-1.17 g particulate organic carbon per L while the average ammonium removal efficiency increased from 14% to 30%. Upon microscopic inspection, microalgal cells were observed growing on the surface of zeolite particles, which indicates that zeolite can support attached microalgal growth. With higher zeolite doses (1 and 5 g L-1) inside the reactor, however, the breaking apart of added zeolite particles into finer particles dramatically increased solution turbidity, which likely was not beneficial for microalgal growth and ammonium removal due to reduced light penetration. This work shows that low doses of zeolite can be used as microcarriers to enhance microalgal biomass concentration and ammonium removal efficiency, while minimizing zeolite dose would likely reduce the turbidity effects.

Regenerative water purification for space applications: Needs, challenges, and technologies towards 'closing the loop'.

Human missions to establish surface habitats on the Moon and Mars are planned in the coming decades. Extraplanetary surface habitat life support systems (LSS) will require new capabilities to withstand anticipated unique, harsh conditions. In order to provide safe, habitable environments for the crew, water purification systems that are robust and reliable must be in place. These water purification systems will be required to treat all sources of water in order to achieve the necessary levels of recovery needed to sustain life over the long-duration missions. Current water recovery and purification systems aboard the International Space Station (ISS) are only partially closed, requiring external inputs and resupply. Furthermore, organic wastes, such as fecal and food wastes, are currently discarded and not recycled. For long-duration missions and habitats, this is not a viable approach. The inability to recycle organic wastes represents a lost opportunity to recover critical elements (e.g., C, H, O, N, P) for subsequent food production, water purification, and atmospheric regeneration. On Earth, a variety of technologies are available to meet terrestrial wastewater treatment needs; however, these systems are rarely completely closed-loop, due to lack of economic drivers, legacy infrastructure, and the (perceived) abundance of resources on Earth. Extraplanetary LSS provides a game-changing opportunity to incentivize the development of completely closed-loop systems. Candidate technologies may be biological, physical, or chemical, with associated advantages and disadvantages. This paper presents a survey of potential technologies, along with their inputs, outputs and requirements, which may be suitable for next-generation regenerative water purification in space. With this information, particular technologies can be down-selected for subsystem integration testing and optimization. In order for future space colonies to have closed-loop systems which minimize consumable inputs and maximize recovery, strategic implementation of a variety of complementary subsystems is needed.

A case of leukocytoclastic vasculitis caused by novel anticoagulant rivaroxaban.

Cutaneous leukocytoclastic vasculitis (LCV) is type of small vessel vasculitis that commonly presents as palpable purpura involving the lower extremities and buttocks. Approximately half of cases are idiopathic, but the disease may be triggered by infection, drug reaction, inflammatory disease, or other causes. We report a case of leukocytoclastic vasculitis secondary to the novel anticoagulant rivaroxaban (Xarelto®).

Scrotal Buschke-Lowenstein tumor in an AIDS patient.

Giant condyloma acuminatum, also known as Buschke-Lowenstein tumor, is a slow-growing neoplasm notable for its size and presentation in the anogenital region. A viral etiology suggests it should be more common in the immunocompromised; however, few reports exist in the literature. The evaluation, treatment, and role of preventative measures are reviewed.

Repeatability of retrobulbar blood flow velocity measured using color Doppler imaging in the Indianapolis Glaucoma Progression Study.

PURPOSE: Determine the repeatability of color Doppler imaging (CDI) measurements in patients with open-angle glaucoma (OAG). PATIENTS AND METHODS: We performed a cross-sectional, observational study of OAG patients participating in the Indianapolis Glaucoma Progression Study. Retrobulbar blood flow velocities and Pourcelot's vascular resistance index (RI) measured with CDI were examined. Two baseline measurements were obtained 1 to 2 weeks apart at the same time of day for all participants. Peak systolic and end diastolic blood flow velocities (PSV/EDV) were measured in the ophthalmic (OA), central retinal (CRA), and nasal and temporal short posterior ciliary arteries (N/TPCA) and RI was calculated. Intraclass correlation coefficient (ICC) between the 2 baselines was calculated. RESULTS: One hundred and sixteen patients with OAG [mean age 65.9 y (SD 10.9 y), 60% female] were examined in both baseline visits. In the OA, the intraobserver ICC for the PSV, EDV, and RI were all above 0.82. In the CRA, the intraobserver ICC for the PSV and RI were both above 0.8, whereas the EDV was 0.64. The intraobserver ICC in the N/TPCA for the PSV, EDV, and RI ranged from 0.71 to 0.88. The interobserver ICC was similar to the intraobserver ICC for the OA and the CRA but was lower than 0.7 in the EDV and RI of the T/NPCA. CONCLUSIONS: Blood flow velocities and calculated vascular resistance of the OA, CRA, and PCAs conducted within 2 weeks in patients with OAG are repeatable. Intraobserver CDI measurements were found more reproducible than interobserver CDI analysis.

Smoke-free laws and secondhand smoke exposure in US non-smoking adults, 1999-2002.

OBJECTIVES: To investigate the relationship between smoke-free law coverage and secondhand smoke (SHS) exposure in the United States non-smoking adult population. DESIGN: We used data from the 1999-2002 National Health and Nutrition Examination Survey, a cross-sectional survey designed to monitor the health and nutritional status of the US population. Serum cotinine levels were available for 5866 non-smoking adults from 57 survey locations. Each location was categorised into one of three groups indicating extensive, limited, and no coverage by a smoke-free law. MAIN OUTCOME MEASURES: The proportion of adults with SHS exposure, defined as having serum cotinine levels > or = 0.05 ng/ml. RESULTS: Among non-smoking adults living in counties with extensive smoke-free law coverage, 12.5% were exposed to SHS, compared with 35.1% with limited coverage, and 45.9% with no law. Adjusting for confounders, men and women residing in counties with extensive coverage had 0.10 (95% confidence interval (CI) 0.06 to 0.16) and 0.19 (95% CI 0.11 to 0.34) times the odds of SHS exposure compared to those residing in counties without a smoke-free law. CONCLUSIONS: These results support the scientific evidence suggesting that smoke-free laws are an effective strategy for reducing SHS exposure.