12 research outputs found
Ground Testing of the EMCS Seed Cassette for Biocompatibility with the Cellular Slime Mold, Dictyostelium Discoideum
The European Modular Cultivation System, EMCS, was developed by ESA for plant experiments. To expand the use of flight verified hardware for various model organisms, we performed ground experiments to determine whether ARC EMCS Seed Cassettes could be adapted for use with cellular slime mold for future space flight experiments. Dictyostelium is a cellular slime mold that can exist both as a single-celled independent organism and as a part of a multicellular colony which functions as a unit (pseudoplasmodium). Under certain stress conditions, individual amoebae will aggregate to form multicellular structures. Developmental pathways are very similar to those found in Eukaryotic organisms, making this a uniquely interesting organism for use in genetic studies. Dictyostelium has been used as a genetic model organism for prior space flight experiments. Due to the formation of spores that are resistant to unfavorable conditions such as desiccation, Dictyostelium is also a good candidate for use in the EMCS Seed Cassettes. The growth substratum in the cassettes is a gridded polyether sulfone (PES) membrane. A blotter beneath the PES membranes contains dried growth medium. The goals of this study were to (1) verify that Dictyostelium are capable of normal growth and development on PES membranes, (2) develop a method for dehydration of Dictyostelium spores with successful recovery and development after rehydration, and (3) successful mock rehydration experiments in cassettes. Our results show normal developmental progression in two strains of Dictyostelium discoideum on PES membranes with a bacterial food source. We have successfully performed a mock rehydration of spores with developmental progression from aggregation to slug formation, and production of morphologically normal spores within 9 days of rehydration. Our results indicate that experiments on the ISS using the slime mold, Dictyostelium discoideum could potentially be performed in the flight verified hardware of the EMCS ARC Seed Cassettes
Utilizing ARC EMCS Seedling Cassettes as Highly Versatile Miniature Growth Chambers for Model Organism Experiments
The aim of our ground testing was to demonstrate the capability of safely putting specific model organisms into dehydrated stasis, and to later rehydrate and successfully grow them inside flight proven ARC EMCS seedling cassettes. The ARC EMCS seedling cassettes were originally developed to support seedling growth during space flight. The seeds are attached to a solid substrate, launched dry, and then rehydrated in a small volume of media on orbit to initiate the experiment. We hypothesized that the same seedling cassettes should be capable of acting as culture chambers for a wide range of organisms with minimal or no modification. The ability to safely preserve live organisms in a dehydrated state allows for on orbit experiments to be conducted at the best time for crew operations and more importantly provides a tightly controlled physiologically relevant growth experiment with specific environmental parameters. Thus, we performed a series of ground tests that involved growing the organisms, preparing them for dehydration on gridded Polyether Sulfone (PES) membranes, dry storage at ambient temperatures for varying periods of time, followed by rehydration. Inside the culture cassettes, the PES membranes were mounted above blotters containing dehydrated growth media. These were mounted on stainless steel bases and sealed with plastic covers that have permeable membrane covered ports for gas exchange. The results showed we were able to demonstrate acceptable normal growth of C.elegans (nematodes), E.coli (bacteria), S.cerevisiae (yeast), Polytrichum (moss) spores and protonemata, C.thalictroides (fern), D.discoideum (amoeba), and H.dujardini (tardigrades). All organisms showed acceptable growth and rehydration in both petri dishes and culture cassettes initially, and after various time lengths of dehydration. At the end of on orbit ISS European Modular Cultivation System experiments the cassettes could be frozen at ultra-low temperatures, refrigerated, or chemically preserved before being returned to Earth for analyses. Our results suggest that with protocol modifications and future verification testing we can utilize the versatile EMCS to conduct tightly controlled experiments inside our culture cassettes for a wide variety of organisms. These physiological experiments would be designed to answer questions at the molecular level about the specific stress responses of space flight
Ground Testing of the EMCS Seed Cassette for Biocompatibility with the Tardigrade, Hypsibius dujardini
The European Modular Cultivation System, EMCS, was developed by ESA for plant experiments. We performed ground testing to determine whether ARC EMCS seed cassettes could be adapted for use with tardigrades for future spaceflight experiments. Tardigrades (water bears) are small invertebrates that enter the tun state in response to desiccation or other environmental stresses. Tardigrade tuns have suspended metabolism and have been shown to be survive exposure to space vacuum, high pressure, temperature and other stresses. For spaceflight experiments using the EMCS, the organisms ideally must be able to survive desiccation and storage in the cassette at ambient temperature for several weeks prior to the initiation of the experiment by the infusion of water to the cassette during spaceflight. The ability of tardigrades to survive extremes by entering the tun state make them ideal candidates for growth experiments in the EMCS cassettes. The growth substratum in the cassettes is a gridded polyether sulfone (PES) membrane. A blotter beneath the PES membrane contains dried growth medium. The goals of our study were to (1) determine whether tardigrades survive and reproduce on PES membranes, (2) develop a consistent method for dehydration of the tardigrades with high recovery rates upon rehydration, (3) to determine an appropriate food source for the tardigrades that can also be dehydrated/rehydrated and (4) successful mock rehydration experiment in cassettes with appropriate food source. We present results that show successful multigenerational growth of tardigrades on PES membranes with a variety of wet food sources. We have successfully performed a mock rehydration with tardigrades and at least one candidate food, protonema of the moss Polytrichum, that supports multigenerational growth and whose spores germinate quickly enough to match tardigrade feeding patterns post rehydration. Our results indicate that experiments on the ISS using the tardigrade, Hypsibius dujardini and other similar species could successfully be performed in the flight verified hardware of the EMCS seed cassettes
Evaluation of Rodent Spaceflight in the NASA Animal Enclosure Module for an Extended Operational Period (up to 35 days)
The National Aeronautics and Space Administration Animal Enclosure Module (AEM) was developed as a self-contained rodent habitat for shuttle flight missions that provides inhabitants with living space, food, water, ventilation, and lighting for shuttle flight missions, and this study reports whether, after minimal hardware modification, the AEM could support an extended term up to 35 days for Sprague-Dawley rats and C57BL/6 female mice for use on the International Space Station. Success was evaluated based on comparison of AEM housed animals to that of vivarium housed and to normal biological ranges through various measures of animal health and well-being, including animal health evaluations, animal growth and body masses, organ masses, rodent food bar consumption, water consumption, and analysis of blood contents. The results of this study confirmed that the AEMs could support 12 adult female C57BL/6 mice for up to 35 days with self-contained RFB and water, and the AEMs could also support 5 adult male Sprague-Dawley rats for 35 days with external replenishment of diet and water. This study has demonstrated the capability and flexibility of the AEM to operate for up to 35 days with minor hardware modification. Therefore, with modifications, it is possible to utilize this hardware on the International Space Station or other operational platforms to extend the space life science research use of mice and rats
Dissecting the Shared Genetic Architecture of Suicide Attempt, Psychiatric Disorders, and Known Risk Factors
Background Suicide is a leading cause of death worldwide, and nonfatal suicide attempts, which occur far more frequently, are a major source of disability and social and economic burden. Both have substantial genetic etiology, which is partially shared and partially distinct from that of related psychiatric disorders. Methods We conducted a genome-wide association study (GWAS) of 29,782 suicide attempt (SA) cases and 519,961 controls in the International Suicide Genetics Consortium (ISGC). The GWAS of SA was conditioned on psychiatric disorders using GWAS summary statistics via multitrait-based conditional and joint analysis, to remove genetic effects on SA mediated by psychiatric disorders. We investigated the shared and divergent genetic architectures of SA, psychiatric disorders, and other known risk factors. Results Two loci reached genome-wide significance for SA: the major histocompatibility complex and an intergenic locus on chromosome 7, the latter of which remained associated with SA after conditioning on psychiatric disorders and replicated in an independent cohort from the Million Veteran Program. This locus has been implicated in risk-taking behavior, smoking, and insomnia. SA showed strong genetic correlation with psychiatric disorders, particularly major depression, and also with smoking, pain, risk-taking behavior, sleep disturbances, lower educational attainment, reproductive traits, lower socioeconomic status, and poorer general health. After conditioning on psychiatric disorders, the genetic correlations between SA and psychiatric disorders decreased, whereas those with nonpsychiatric traits remained largely unchanged. Conclusions Our results identify a risk locus that contributes more strongly to SA than other phenotypes and suggest a shared underlying biology between SA and known risk factors that is not mediated by psychiatric disorders.Peer reviewe
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Effect of dairy fat and milk product supplementation on plasma lipids and low-density lipoprotein metabolism in the guinea pig.
Effects of dairy fat composition on LDL metabolism were measured in male guinea pigs fed 15% (w/w) fat diets, either butterfat (BF) or a synthetic butter-like fat mix (SBF). Dietary groups were: whole milk powder (WM), skim milk powder-SBF (SM/S), casein-SBF (C/S), and skim milk powder-BF (SM/B). A hypocholesterolemic effect was observed in guinea pigs fed the WM (plasma cholesterol, 1.5 mmol/L) diet compared to all other diet groups (3. 1 mmol/L). Hepatic LDL receptor B(max) and K(d) values were not different between WM and SM/B diet groups. Animals fed the WM or SM/B diets had higher HMG-CoA reductase activities than animals fed the SM/S or C/S diets. The results demonstrate that butterfat intake results in a hypercholesterolemic response of plasma and liver; however, the predicted hypercholesterolemic effect of miikfat was not observed with the WM diet compared to the SBF and BF fats. These data suggest that some factor(s) in milk, other than the milkfat itself, negates the hypercholesterolemic effect of dairy fat. Additional experiments evaluated the effects of diet supplemented with whole milk and partially reconstituted milk fractions in guinea pigs fed diets containing 15% (w/w) butter-palm oil (1:1) fat, with or without liquid milk products. Dietary groups were: water (WE), non-processed whole milk (NPWM), re-constituted whole milk (RCWM), buttermilk-enriched skim milk (BMSM), butterserum-enriched skim milk (BSSM), and butteroil-skim milk (BOSM). Plasma total cholesterol (3.0 ± 1.4 versus 2.6 ± 0.1 mmol/L) and hepatic cholesterol (8.1 ± 0.6 versus 9.0 ± 1.2 μmol/g) were not different between WE and milk product treated diets. LDL peak densities and calculated diameters, and hepatic LDL receptor B(max) and K(d) were not different among diets. In summary, potential plasma cholesterol lowering factor(s) associated with whole milk may exist in buttermilk or butterserum but can not be identified; however, a diet supplemented with liquid milk products providing up to 46% of the daily energy intake, with higher total fat (1.4-fold) and dietary cholesterol (2.3-fold) did not increase plasma cholesterol and triacylglycerol levels or alter LDL metabolism in the guinea pig
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Water quality of gray water for reuse
This study was designed to evaluate the safety of gray water for reuse purposes. The physical and chemical quality of treated gray water met water reuse standards set by the State of Arizona for surface irrigation purposes. The number of microorganisms in gray water significantly decreased after biological treatment and sand filtration. However, the number of fecal coliform bacteria in treated gray water was still higher than the standard for reuse as set by the State of Arizona for surface irrigation. This is also true for rain water which was stored in a tank. No indigenous Salmonella were isolated from gray water. It was found that both Salmonella typhimurium and Shigella dysenteriae, seeded into gray water, can persist for at least several days. This implied that there may be some risk associated with gray water reuse when the gray water contains these pathogenic bacteria.hydrology collectio
Application of frass from black soldier fly larvae treatment of cattle dung in pulp and papermaking
Abstract Cattle dung treatments in Taiwan have developed a process called Black soldier fly larvae (BSFL) treatment, which can digest cow dung and generate the frass (larvae drops), the residue fiber in cow dung. This study aims to assess frass for its potential in pulp and papermaking, considering its chemical compositions, appearance, and fiber morphology, and also evaluate its suitability for pulping by soda method to create added value. The frass exhibits favorable material properties for pulping and papermaking, including a high holocellulose (67.37%) and α-cellulose (48.00%) content, along with a lower ash content (4.61%); the microstructure and surface mesoporous pores benefit for pulping; and the nonwood-fiber-like fiber morphology. The pulping experiment shows that 7% NaOH and 75 min of pulping conditions result in proper disintegration of fiber, and the highest accepts ratio (34.06%). The NaOH causes fiber disintegration during pulping, resulting in a higher strength property of the handsheet. The frass pulp blended with TOCC can achieve the ring crush index standards required for cardboard products. In summary, the frass from BSFL treatment of cattle dung can be utilized in pulp and papermaking to enhance circular utilization value
BCC skin cancer diagnosis based on texture analysis techniques
In this paper, we present a texture analysis based method for diagnosing the Basal Cell Carcinoma (BCC) skin cancer using optical images taken from the suspicious skin regions. We first extracted the Run Length Matrix and Haralick texture features from the images and used a feature selection algorithm to identify the most effective feature set for the diagnosis. We then utilized a Multi-Layer Perceptron (MLP) classifier to classify the images to BCC or normal cases. Experiments showed that detecting BCC cancer based on optical images is feasible. The best sensitivity and specificity we achieved on our data set were 94% and 95%, respectively
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Microbial Quality of Gray Water for Reuse
From the Proceedings of the 1986 Meetings of the Arizona Section - American Water Resources Association, Hydrology Section - Arizona-Nevada Academy of Science and the Arizona Hydrological Society - April 19, 1986, Glendale Community College, Glendale, ArizonaAs the scarcity of water and the price of municipal water inevitably increase, gray water reuse may become an inexpensive and viable alternative for such purposes as irrigation, lawn maintenance and water closet flushing. However, some problems do exist. The microbial and chemical content of gray water includes agents that may present public health problems. The purpose of this study was to determine the general microbial composition of gray water using standard plate counts and selective media at specific sites (shower/bath, wash cycle and rinse cycle of a clothes washing machine) and the general chemical and physical properties of gray water at these same sites (phosphate, ammonia, chloride, pH, TDS and turbidity). Samples were taken from a diverse group of families with and without children (1 ½ - 9 years). Standard plate count bacteria ranged from 10⁵ to 10¹⁰ colony forming units (CFU)₄/100 ml. Shower and bath water contained an average of 10⁴ to 10⁶ CFU/100 ml of coliforms. Failies with children produced wash cycle gray water containing 10⁶ CFU /100 ml of fecal coliforms. Ammonia concentrations varied proportionally with bacterial concentrations while phosphate varied inversely with bacterial growth. Bacterial numbers increased one order of magnitude during storage of gray water.This article is part of the Hydrology and Water Resources in Arizona and the Southwest collections. Digital access to this material is made possible by the Arizona-Nevada Academy of Science and the University of Arizona Libraries. For more information about items in this collection, contact [email protected]