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1.
Life Sci Space Res (Amst) ; 22: 68-75, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31421850

RESUMO

The nutrient delivery system is one of the most important hardware components in tomato (Lycopersicon esculentum Mill.) production in Bio-regenerative Life Support Systems (BLSS) for future long-term space mission. The objective of this study was to investigate the influences of different nutrient delivery systems (aeroponics, hydroponics and porous tube-vermiculite) on the growth, photosynthetic characteristics, antioxidant capacity, biomass yield and quality of tomato during its life cycle. The results showed that the dry weight of aeroponics and porous tube-vermiculite treatment group was 1.95 and 1.93 g/fruit, but the value of hydroponics treatment group was only 1.56 g/fruit. Both tomato photosynthesis and stomatal conductance maximized at the development stage and then decreased later in senescent leaves. At the initial stage and the development stage, POD activities in the aeroponics treatment were higher than other two treatments, reached 3.6 U/mg prot and 4.6 U/mg prot, respectively. The fresh yield 431.3 g/plant of hydroponics treatment group was lower. At the same time, there were no significant differences among nutrient delivery systems in the per fruit fresh mass, which was 14.2-17.5 g/fruit.


Assuntos
Sistemas Ecológicos Fechados , Lycopersicon esculentum/crescimento & desenvolvimento , Biomassa , Hidroponia , Lycopersicon esculentum/química , Fotossíntese , Astronave
3.
Life Sci Space Res (Amst) ; 21: 22-24, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31101152

RESUMO

The present study discusses physicochemical methods of organic waste processing in closed biotechnical life support systems (BTLSS). Sanitary and household cotton wastes were processed by the method of wet combustion in hydrogen peroxide using an alternating current electric field - a promising physicochemical method for organic waste processing in the BTLSS. The highest efficiency of the process (in terms of power consumption, duration of the process, and oxidation rate) was achieved in experiments with oxidation of a combination of cotton fabrics and urea-containing wastes such as human urine and feces. The reason for this must be that urea is a reactive aqueous solvent of cellulose.


Assuntos
Sistemas Ecológicos Fechados , Produtos Domésticos/análise , Sistemas de Manutenção da Vida , Gerenciamento de Resíduos/métodos , Resíduos/análise , Humanos , Oxirredução , Têxteis
4.
Life Sci Space Res (Amst) ; 21: 40-48, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31101154

RESUMO

Light emitting diode (LED) lighting technology for crop production is advancing at a rapid pace, both in terms of the technology itself (e.g., spectral composition and efficiency), and the research that the technological advances have enabled. The application of LED technology for crop production was first explored as a tool for improving the safety and reliability of plant-based bioregenerative life-support systems for long duration human space exploration. Developing and optimizing the lighting environment (spectral quality and quantity) for bioregenerative life-support applications and other controlled environment plant production applications, such as microgreens and sprout production, continues to be an active area of research and LED technology development. This study examines the influence of monochromatic and dichromatic red and blue light on the early development of six food crop species; Cucumis sativa, Solanum lycopersicum, Glycine max, Raphanus sativus, Pisum sativum, and Capsicum annum. Results support previous findings that light responses are often species specific. The results also support the assertion that monochromatic light can interfere with the normal interaction of various photoreceptors (co-action disruption) resulting in intermediate and sometimes unpredictable responses to a given light environment. The nature of the responses reported inform both bioregenerative life-support designs as well as light quality selection for the production of controlled environment crops.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Produtos Agrícolas/efeitos da radiação , Sistemas de Manutenção da Vida , Luz , Plântula/crescimento & desenvolvimento , Plântula/efeitos da radiação , Capsicum/crescimento & desenvolvimento , Capsicum/efeitos da radiação , Produção Agrícola , Cucumis sativus/crescimento & desenvolvimento , Cucumis sativus/efeitos da radiação , Sistemas Ecológicos Fechados , Ervilhas/crescimento & desenvolvimento , Ervilhas/efeitos da radiação , Raphanus/crescimento & desenvolvimento , Raphanus/efeitos da radiação , Solanum tuberosum/crescimento & desenvolvimento , Solanum tuberosum/efeitos da radiação , Soja/crescimento & desenvolvimento , Soja/efeitos da radiação
5.
Prensa méd. argent ; 105(2): 47-52, apr 2019. fig
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1025584

RESUMO

Trichobezoars are an unusual pathology that appears generally in young adolescents associated with psychiatric disorders. The clinical presentation is very varied. The diagnosis is suspected by the clinical records of teen agers with trichophagia and trichotillomania and the digestive disorders are confirmed by the results of the endoscopy, the same as with images toward the therapeutic management. Undowbtly the treatment is surgical, and continuation with the psychiatric treatment is essential to avoid a recidival of the disease. Bezoar is a concretion formed in the alimentary tract, and according to the substances forming the ball, we find trichobezoar (foodball). The Rapunzel syndrome is an unusual complication of individual bezoar. When the trichobezoar located in the stomach extends through the pylorus into the small intestine and the right colon, is known as Rapunzel syndrome, that is an extremely rare gastric condition in humans. It is a rare form of trichobezoar, occurring in psychiatric patients with the trichobezoar (hairball) located in the stomach. The syndrome is named after the long haired girl Rapunzel in the fairy tale of the brothers Grimm. Most bezoars in teen agers are trichobezoars from swallowed hair. A 28-year-old patient is presented, with abdominal pain and vomiting, on the general physical examination the patient revealed a severe weight loss. Later on, through a gastrostomy, appeared the trichobezoar, being removed with good postsurgical resullts


Assuntos
Humanos , Feminino , Adulto , Estômago , Tricotilomania/patologia , Bezoares/cirurgia , Bezoares/diagnóstico , Bezoares/patologia , Bezoares/psicologia , Sistemas Ecológicos Fechados
6.
Life Sci Space Res (Amst) ; 20: 30-34, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30797432

RESUMO

Closure from the earth's atmosphere is a critical test of an ecosystem's ability to function. In our earlier testing of autotrophic Closed Ecological Systems (CESs), a C:N ratio of 26.4 (3.3 mM NaHCO3 and 0.125 mM NaNO3) supported algal and Daphnia populations for months, but developed extreme pH values (∼11 ungrazed, >10, grazed), suggesting that the systems were carbon-limited. Only approximately half the HCO3- (bicarbonate) would be expected to be available to green algae, the other portion becoming CO3-2 (carbonate). In an experiment described here, CESs were developed to explore a greater range of C:N ratios. To keep the medium from becoming too osmotically concentrated, NaNO3 was reduced to 0.0312 mM and NaHCO3 tested at 3.3, 13.2, and 26.4 mM, resulting in nominal C:N ratios of 105, 422, and 845. However, additional carbon was not beneficial to long-term survival of the organisms. The algal abundance was relatively insensitive to C:N ratio; greater concentrations of C were not beneficial. Daphnia populations were sensitive to C:N ratio and persisted longer at the lowest C:N ratio of 105. All of the C:N ratios tested in these CESs are outside of the expected range suggested from ecological studies, which is based on the Redfield Ratio of 6.625 C:N, the expected chemical composition of algae. Two potential explanations for the apparent high C demand in our CESs are suggested by the literature. The first is production of fatty algal cells, e.g., one of the algal species, Scenedesmus obliquus, is reported to produce high-lipid cells that could have a higher C:N ratio than the Redfield Ratio. The second is "carbon overconsumption," which has been suggested for N-limited marine phytoplankton communities dominated by diatoms or nutrient deficient algal communities dominated by small cells that are under-represented by chlorophyll a measurements. The unexpected C dynamics found in our CES tests could be relevant to the design of biological life support systems that must be provisioned with adequate elements for long-term ecosystem functionality. If the actual demand for C is underestimated, its storage may be inadequate.


Assuntos
Carbono/metabolismo , Daphnia/fisiologia , Sistemas Ecológicos Fechados , Sistemas de Manutenção da Vida , Fitoplâncton/fisiologia , Animais , Daphnia/metabolismo , Nitrogênio/metabolismo , Fitoplâncton/metabolismo
7.
Life Sci Space Res (Amst) ; 20: 35-52, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30797433

RESUMO

Bioregenerative technologies, in particular algae photobioreactors, have the potential to provide closed-loop environmental control and life support for human space flight, if robust enough for long-duration deep space missions. This paper reviews the failure modes, causes, and effects of an algal photobioreactor system for use in space flight environmental control and life support applications. The likelihood and severity for each failure is estimated, and associated mitigation or contingency plans are described. Failure modes can stem from either the algae cellular physiology or the engineered system needed for the application and are grouped in this paper accordingly.


Assuntos
Sistemas Ecológicos Fechados , Sistemas de Manutenção da Vida/instrumentação , Microalgas/fisiologia , Fotobiorreatores , Astronave/instrumentação , Humanos , Hidrodinâmica
8.
Life Sci Space Res (Amst) ; 20: 53-61, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30797434

RESUMO

The present study deals with the development of the principles and conditions of fish waste mineralization using the method of wet combustion with hydrogen peroxide in alternating electromagnetic field and describes testing mineralized human waste and fish waste as sources of nutrients for plants in the biotechnical human life support system (BTLSS). The study shows that mineralization of fish waste in the wet combustion reactor should be performed in the presence of readily oxidized organic matter, represented by human waste, as an activator of oxidation. Re-mineralization of the sediment in the mixture of hydrogen peroxide and nitric acid in the wet combustion reactor converts mineral elements bound in the sediment into the form available to plants. Using mineralized fish waste as an additional source of mineral elements in the nutrient solutions for growing plants based on mineralized human waste is a way to reduce the amounts of mineral elements added to the solution to replenish it, enabling fuller closure of material loops in the BTLSS.


Assuntos
Biomassa , Sistemas Ecológicos Fechados , Peixes/fisiologia , Sistemas de Manutenção da Vida , Minerais/metabolismo , Plantas/metabolismo , Gerenciamento de Resíduos/métodos , Animais , Humanos , Estado Nutricional , Oxirredução
9.
Life Sci Space Res (Amst) ; 20: 62-71, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30797435

RESUMO

Extended human spaceflight missions require not only the processing, but also the recycling of human waste streams in bio-regenerative life support systems, which are rich in valuable resources. The Combined Regenerative Organic food Production® project of the German Aerospace Center aims for recycling human metabolic waste products to produce useful resources. A biofiltration process based on natural communities of microorganisms has been developed and tested. The processed aqueous solution is, among others, rich in nitrogen present as nitrate. Nitrate is one of the main nutrients required for plant cultivation, resulting in strong synergies between the developed recycling process and plant cultivation. The latter is envisaged as the basis of future bio-regenerative life support systems, because plants do consume carbon dioxide, water and nutrients in order to produce oxygen, water, food and inedible biomass. This paper describes a series of plant cultivation experiments performed with synthetic urine processed in a bioreactor. The aim of the experiments was to investigate the feasibility of growing tomato plants with this solution. The results of the experiments show that such cultivation of tomato plants is generally feasible, but that the plants are less productive. The fruit fresh weight per plant is less compared to plants grown with the half-strength Hoagland reference solution. This lack in production is caused by imbalances of sodium, chloride, potassium, magnesium and ammonium in the solution gained from recycling the synthetic urine. An attempt on adjusting the produced bioreactor solution with additional mineral fertilizers did not show a significant improvement in crop yield.


Assuntos
Materiais Biomiméticos/química , Sistemas Ecológicos Fechados , Lycopersicon esculentum/crescimento & desenvolvimento , Nutrientes/farmacologia , Desenvolvimento Vegetal , Urina/química , Gerenciamento de Resíduos/métodos , Humanos , Lycopersicon esculentum/efeitos dos fármacos , Voo Espacial
10.
Life Sci Space Res (Amst) ; 19: 63-67, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30482284

RESUMO

The study describes a small closed ecosystem used to test technologies to be further employed in full-scale manned closed ecosystems. The experimental ecosystem is designed to use a certain portion of human metabolism, which is included in the gas, water, and organic waste loops of the system. In this experimental ecosystem, gas and water loops are fully closed, and the model enables processing of human waste and plant inedible biomass. A physicochemical method is used to remove pollutants from the air in the system. A human takes part in the gas exchange of the system through its respiration loop. This experimental ecosystem can be used for testing and improving new technologies to be further used in the future space stations.


Assuntos
Sistemas Ecológicos Fechados , Sistemas de Manutenção da Vida , Fotossíntese , Plantas/metabolismo , Água/metabolismo , Biodegradação Ambiental , Biomassa , Dióxido de Carbono/metabolismo , Fezes/química , Humanos , Esterco/análise , Oxigênio/metabolismo , Urina/química
11.
J R Soc Interface ; 15(147)2018 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-30333242

RESUMO

One of the biggest perceived challenges in building megastructures, such as the space elevator, is the unavailability of materials with sufficient tensile strength. The presumed necessity of very strong materials stems from a design paradigm which requires structures to operate at a small fraction of their maximum tensile strength (usually, 50% or less). This criterion limits the probability of failure by giving structures sufficient leeway in handling stochastic components, such as variability in material strength and/or external forces. While reasonable for typical engineering structures, low working stress ratios-defined as operating stress as a fraction of ultimate tensile strength-in the case of megastructures are both too stringent and unable to adequately control the failure probability. We draw inspiration from natural biological structures, such as bones, tendons and ligaments, which are made up of smaller substructures and exhibit self-repair, and suggest a design that requires structures to operate at significantly higher stress ratios, while maintaining reliability through a continuous repair mechanism. We outline a mathematical framework for analysing the reliability of structures with components exhibiting probabilistic rupture and repair that depend on their time-in-use (age). Further, we predict time-to-failure distributions for the overall structure. We then apply this framework to the space elevator and find that a high degree of reliability is achievable using currently existing materials, provided it operates at sufficiently high working stress ratios, sustained through an autonomous repair mechanism, implemented via, e.g. robots.


Assuntos
Sistemas Ecológicos Fechados , Elevadores e Escadas Rolantes , Meio Ambiente Extraterreno , Arquitetura de Instituições de Saúde , Resistência à Tração , Fenômenos Biomecânicos , Gravidade Alterada , Humanos , Sistemas de Manutenção da Vida
12.
Life Sci Space Res (Amst) ; 18: 29-34, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30100145

RESUMO

The present study addresses the ways to increase the closure of biotechnical life support systems (BTLSS) for space applications. A promising method of organic waste processing based on "wet combustion" in hydrogen peroxide developed at the IBP SB RAS to produce fertilizers for higher plants is discussed. The method is relatively compact, energy efficient, productive, and eco-friendly. However, about 4-6 g/L of recalcitrant sediment containing such essential nutrients as Ca, Mg, P, Fe, Cu, Mn, and Zn precipitates after the initial process. These elements are unavailable to plants grown hydroponically and, thus, drop out of the cycling as dead-end products. Possible methods of dissolving that sediment have been studied. Results of experiments show that the most promising method is additional oxidation of the sediment in HNO3 + H2O2. By using the new technological process, which only involves substances synthesized inside the BTLSS material flows, more than 90% of each nutrient can be converted into the form available to plants in irrigation solutions, thus returning them into the material cycling. The results obtained in this study show the efficacy of supplementing the irrigation solutions with the mineral nutrients after sediment dissolution. Lettuce plants grown as the test object on the newly prepared irrigation solutions produced the yield that was more than twice higher than the yield produced on the nutrient solutions prepared without the sediment conversion into a soluble form. Composition of the gases emitted during this process has been analyzed. Dynamics of oxidation of the small fractions of a wax-like sediment remaining after the initial sediment dissolution in HNO3 + H2O2 in the BTLSS soil-like substrate has been studied. The entire technological scheme aimed at the full inclusion of all human wastes into the BTLSS cycling has been suggested and discussed. A process scheme of including products of human waste processing in the biotic cycle of the BTLSS is discussed in the conclusion.


Assuntos
Sistemas de Manutenção da Vida , Reciclagem/métodos , Voo Espacial , Gerenciamento de Resíduos , Resíduos/análise , Sistemas Ecológicos Fechados , Estudos de Viabilidade , Humanos , Peróxido de Hidrogênio/química , Nitratos/química , Oxirredução
13.
Curr Protoc Plant Biol ; 3(2): e20069, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29927120

RESUMO

In vivo isotopic labeling empowers proteomic and metabolomic analyses to resolve relationships between the molecular composition, environment, and phenotype of an organism. Carbon-13 is particularly useful for plant labeling as it can be introduced via 13 CO2 gas and readily assimilated into plant metabolic systems through natural carbon fixation. While short-term labeling experiments can be performed within a simple sealed enclosure, long-term growth in an isolated environment raises many challenges beyond nutrient availability and buildup of metabolic waste. Viable growth conditions must be maintained by means that do not compromise the integrity of the carbon-13 enrichment. To address these issues, an automated growth chamber equipped with countermeasures to neutralize stresses and ensure high isotopic enrichment throughout the life cycle of the plant has been developed. The following describes this growth chamber and its use in an example 130-day growth of ten soybean plants to full maturity, achieving 100% carbon-13 enrichment of new seed tissue. © 2018 by John Wiley & Sons, Inc.


Assuntos
Isótopos de Carbono , Sistemas Ecológicos Fechados , Marcação por Isótopo , Soja/crescimento & desenvolvimento , Dióxido de Carbono/metabolismo , Sementes , Soja/metabolismo
14.
Sci Rep ; 8(1): 8264, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844534

RESUMO

Detecting the influence of psychological stress is particularly important in prolonged space missions. In this study, we determined potential markers of psychological stress in a confined environment. We examined 23 Japanese subjects staying for 2 weeks in a confined facility at Tsukuba Space Center, measuring salivary, skin, and facial image parameters. Saliva was collected at four points in a single day to detect diurnal variation. Increases in salivary cortisol were detected after waking up on the 4th and 11th days, and at 15:30 on the 1st and in the second half of the stay. Transepidermal water loss (TEWL) and sebum content of the skin were higher compared with outside the facility on the 4th and 1st days respectively. Increased IL-1ß in the stripped stratum corneum was observed on the 14th day, and 7 days after leaving. Differences in facial expression symmetry at the time of facial expression changes were observed on 11th and 14th days. Thus, we detected a transition of psychological stress using salivary cortisol profiles and skin physiological parameters. The results also suggested that IL-1ß in the stripped stratum corneum and facial expression symmetry are possible novel markers for conveniently detecting psychological stress.


Assuntos
Biomarcadores/metabolismo , Sistemas Ecológicos Fechados , Hidrocortisona/metabolismo , Interleucina-1beta/metabolismo , Saliva/metabolismo , Sebo/metabolismo , Estresse Psicológico/diagnóstico , Adulto , Ritmo Circadiano , Expressão Facial , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Pele , Voo Espacial , Fatores de Tempo , Perda Insensível de Água , Adulto Jovem
15.
Life Sci Space Res (Amst) ; 16: 8-17, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29475523

RESUMO

An Environmental Control and Life Support System (ECLSS) is necessary for humans to survive in the hostile environment of space. As future missions move beyond Earth orbit for extended durations, reclaiming human metabolic waste streams for recycled use becomes increasingly important. Historically, these functions have been accomplished using a variety of physical and chemical processes with limited recycling capabilities. In contrast, biological systems can also be incorporated into a spacecraft to essentially mimic the balance of photosynthesis and respiration that occurs in Earth's ecosystem, along with increasing the reuse of biomass throughout the food chain. In particular, algal photobioreactors that use Chlorella vulgaris have been identified as potential multifunctional components for use as part of such a bioregenerative life support system (BLSS). However, a connection between the biological research examining C. vulgaris behavior and the engineered spacecraft cabin environmental conditions has not yet been thoroughly established. This review article characterizes the ranges of prior and expected cabin parameters (e.g. temperature, lighting, carbon dioxide, pH, oxygen, pressure, growth media, contamination, gravity, and radiation) and reviews algal metabolic response (e.g. growth rate, composition, carbon dioxide fixation rates, and oxygen evolution rates) to changes in those parameters that have been reported in prior space research and from related Earth-based experimental observations. Based on our findings, it appears that C. vulgaris offers many promising advantages for use in a BLSS. Typical atmospheric conditions found in spacecraft such as elevated carbon dioxide levels are, in fact, beneficial for algal cultivation. Other spacecraft cabin parameters, however, introduce unique environmental factors, such as reduced total pressure with elevated oxygen concentration, increased radiation, and altered gravity, whose effects on the biological responses of C. vulgaris are not yet well understood. A summary of optimum growth parameter ranges for C. vulgaris is presented in this article as a guideline for designing and integrating an algal photobioreactor into a spacecraft life support system. Additional research challenges for evaluating as of yet uncharacterized parameters are also identified in this article that have the potential for improving spaceflight applications as well as terrestrial aquatic algal cultivation systems.


Assuntos
Chlorella vulgaris/crescimento & desenvolvimento , Sistemas Ecológicos Fechados , Sistemas de Manutenção da Vida , Astronave/instrumentação , Humanos
16.
Microbiome ; 5(1): 129, 2017 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-28974259

RESUMO

BACKGROUND: The Mars500 project was conceived as the first full duration simulation of a crewed return flight to Mars. For 520 days, six crew members lived confined in a specifically designed spacecraft mock-up. The herein described "MIcrobial ecology of Confined Habitats and humAn health" (MICHA) experiment was implemented to acquire comprehensive microbiota data from this unique, confined manned habitat, to retrieve important information on the occurring microbiota dynamics, the microbial load and diversity in the air and on various surfaces. In total, 360 samples from 20 (9 air, 11 surface) locations were taken at 18 time-points and processed by extensive cultivation, PhyloChip and next generation sequencing (NGS) of 16S rRNA gene amplicons. RESULTS: Cultivation assays revealed a Staphylococcus and Bacillus-dominated microbial community on various surfaces, with an average microbial load that did not exceed the allowed limits for ISS in-flight requirements indicating adequate maintenance of the facility. Areas with high human activity were identified as hotspots for microbial accumulation. Despite substantial fluctuation with respect to microbial diversity and abundance throughout the experiment, the location within the facility and the confinement duration were identified as factors significantly shaping the microbial diversity and composition, with the crew representing the main source for microbial dispersal. Opportunistic pathogens, stress-tolerant or potentially mobile element-bearing microorganisms were predicted to be prevalent throughout the confinement, while the overall microbial diversity dropped significantly over time. CONCLUSIONS: Our findings clearly indicate that under confined conditions, the community structure remains a highly dynamic system which adapts to the prevailing habitat and micro-conditions. Since a sterile environment is not achievable, these dynamics need to be monitored to avoid spreading of highly resistant or potentially pathogenic microorganisms and a potentially harmful decrease of microbial diversity. If necessary, countermeasures are required, to maintain a healthy, diverse balance of beneficial, neutral and opportunistic pathogenic microorganisms. Our results serve as an important data collection for (i) future risk estimations of crewed space flight, (ii) an optimized design and planning of a spacecraft mission and (iii) for the selection of appropriate microbial monitoring approaches and potential countermeasures, to ensure a microbiologically safe space-flight environment.


Assuntos
Espaços Confinados , Sistemas Ecológicos Fechados , Marte , Microbiota , Voo Espacial , Simulação de Ambiente Espacial , Astronave , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Microbiota/genética , Microbiota/fisiologia , RNA Ribossômico 16S
17.
Dev Dyn ; 246(11): 802-806, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28493325

RESUMO

Populations of annual killifishes persist in temporary water bodies over the dry season through the expression of diapause in their drought-resistant embryos. Environmental cues may influence expression of the diapause phenotype during embryonic incubation. Millerichthys robustus is the only annual killifish distributed in North America. The aim of this review is to analyze the ecology of M. robustus development and contrast this with that of annual killifishes in austral locations. The temporary water bodies inhabited by M. robustus present the following environmental conditions: flood, drought, and humidity. During the flooding period, the environment presents the lowest temperatures, shortest photoperiod, and highest precipitation, and embryos were found in diapause I. The drought period features the highest temperatures and lowest precipitation, and embryos were found in diapause II. In contrast, during the humid period at the beginning of the rainy season, embryos were found in diapause I, II, and III, associated with the longer photoperiod and high temperatures. These dynamics of the diapause phenotypes can be explained by a combination of the strategies of phenotypic plasticity during flood and drought periods, and bet-hedging during the humid period. Moreover, the microenvironmental conditions in which embryos were buried could influence developmental trajectories. Developmental Dynamics 246:802-806, 2017. © 2017 Wiley Periodicals, Inc.


Assuntos
Adaptação Fisiológica , Ciprinodontiformes/fisiologia , Diapausa/fisiologia , Sistemas Ecológicos Fechados , Animais , Secas , Embrião não Mamífero , Inundações , Umidade , Peixes Listrados
18.
Astrobiology ; 16(12): 925-936, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27912029

RESUMO

To conduct crewed simulation experiments of bioregenerative life support systems on the ground is a critical step for human life support in deep-space exploration. An artificial closed ecosystem named Lunar Palace 1 was built through integrating efficient higher plant cultivation, animal protein production, urine nitrogen recycling, and bioconversion of solid waste. Subsequently, a 105-day, multicrew, closed integrative bioregenerative life support systems experiment in Lunar Palace 1 was carried out from February through May 2014. The results show that environmental conditions as well as the gas balance between O2 and CO2 in the system were well maintained during the 105-day experiment. A total of 21 plant species in this system kept a harmonious coexistent relationship, and 20.5% nitrogen recovery from urine, 41% solid waste degradation, and a small amount of insect in situ production were achieved. During the 105-day experiment, oxygen and water were recycled, and 55% of the food was regenerated. Key Words: Bioregenerative life support systems (BLSS)-Space agriculture-Space life support-Waste recycle-Water recycle. Astrobiology 16, 925-936.


Assuntos
Sistemas de Manutenção da Vida , Marte , Lua , Voo Espacial , Animais , Atmosfera , Biomassa , Produtos Agrícolas/crescimento & desenvolvimento , Sistemas Ecológicos Fechados , Metabolismo Energético , Alimentos , Humanos , Umidade , Oxigênio/análise , Resíduos Sólidos , Temperatura , Fatores de Tempo , Água
19.
Dokl Biochem Biophys ; 470(1): 316-318, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27817031

RESUMO

Methods of physicochemical further oxidation of hardly soluble sediment obtained from "wet combustion" of human exometabolites applied to space-purpose Bio Technological Life Support Systems (BTLLS) were studied. Most hardly dissoluble sediment containing Ca, P, Mg, and other essential plant nutrition elements were shown to dissolve in H2O2 and HNO3 aqueous media activated by alternating electric current. Dissolved additional mineral elements allowed (as demonstrated for lettuce) to increase the productivity of BTLLS phototrophic unit plants more than twice, which is comparable to their productivity on standard Knop solution with balanced chemical composition. Thus, dissolved mineral elements can be involved into BTLLS turnover process and increase its closure degree.


Assuntos
Sistemas Ecológicos Fechados , Eletricidade , Elementos , Engenharia Sanitária/métodos , Humanos , Peróxido de Hidrogênio/química , Concentração de Íons de Hidrogênio , Alface/crescimento & desenvolvimento , Ácido Nítrico/química , Oxirredução , Solubilidade , Ureia/química , Água/química
20.
Life Sci Space Res (Amst) ; 10: 1-16, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27662782

RESUMO

The cultivation of higher plants occupies an essential role within bio-regenerative life support systems. It contributes to all major functional aspects by closing the different loops in a habitat like food production, CO2 reduction, O2 production, waste recycling and water management. Fresh crops are also expected to have a positive impact on crew psychological health. Plant material was first launched into orbit on unmanned vehicles as early as the 1960s. Since then, more than a dozen different plant cultivation experiments have been flown on crewed vehicles beginning with the launch of Oasis 1, in 1971. Continuous subsystem improvements and increasing knowledge of plant response to the spaceflight environment has led to the design of Veggie and the Advanced Plant Habitat, the latest in the series of plant growth systems. The paper reviews the different designs and technological solutions implemented in higher plant flight experiments. Using these analyses a comprehensive comparison is compiled to illustrate the development trends of controlled environment agriculture technologies in bio-regenerative life support systems, enabling future human long-duration missions into the solar system.


Assuntos
Sistemas Ecológicos Fechados , Ambiente Controlado , Desenvolvimento Vegetal , Voo Espacial , Humanos
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