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To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jue.2006.05.003 Byline: Siqi Zheng (a), Yuming Fu (b), Hongyu Liu (a) Keywords: Bid-rent gradient; Urban spatial structure; Location choice; Housing markets; Transition economies Abstract: In a monocentric city with a well-functioning residential market, Pareto-efficient spatial equilibrium entails the sorting of residents according to their bid-rent gradient in descending order away from city center. Violation of this sorting condition creates opportunities for Pareto-improving trading of locations and can be sustained only if the market is hindered. We propose a simple ordered-location-choice model using matched location and location-preference data of individual households to examine violations of the Pareto-efficient spatial sorting condition. In so doing we are able to identify population groups facing housing-choice hindrances. We find in a sample of Chinese cities undergoing housing market liberalization that poor marketability of the previously state-provided homes, inadequate provision of housing finance, and spatial mismatch between job-market and housing-market opportunities contribute to a Pareto-inefficient spatial structure. Author Affiliation: (a) Institute of Real Estate Studies, Tsinghua University, Beijing 100084, China (b) Department of Real Estate, National University of Singapore, 4 Architecture Drive, Singapore, 117566 Article History: Received 13 March 2005; Revised 8 May 2006

When a developer acquires land below its market rate, an industry receives abnormally high returns on purchase of the land.

This article evaluates how restrictions on the density of development sites effects land use regulations, by presenting a model which identifies the ratio of building space to lot area. The affects of land prices on redevelopment sites in Shanghai, China's emerging real estate market are measured., This article evaluates how restrictions on the density of development sites effects land use regulations, by presenting a model which identifies the ratio of building space to lot area. The affects of land prices on redevelopment sites in Shanghai, China's emerging real estate market are measured.

Issues regarding the intention to buy commodity housing by Chinese urban workers are discussed. A survey shows this intention to be sensitive to various incentives and the access to publicly subsidized housing is at least as important as the affordability of commodity housing in discouraging private home ownership.

Plants have evolved various strategies for assembling rhizosphere microbiota in response to abiotic stressors. However, our understanding of rhizosphere bacterial community assembly and function under microgravity conditions is limited, especially when soil serves as the growth substrate. Here, using microgravity analogs, we compared the bacterial communities in both the rhizosphere and bulk soil of wheat plants grown in soil under normal gravity and simulated microgravity conditions through 16S rRNA gene amplicon sequencing. Our results revealed a decrease in rhizosphere bacterial diversity and an increase in the relative abundance of plant pathogens under simulated microgravity. Furthermore, simulated microgravity amplifies the contribution of deterministic processes in the assembly of rhizosphere bacterial communities and promotes functional redistribution of rhizosphere bacteria. To validate the roles of rhizosphere-enriched bacteria, we generated a synthetic microbial community (SynCom) of Methylorubrum extorquens NCIMB 9399 , Paracoccus marcusii MH1 , Massilia haematophila CCUG 38318 , and Brevibacillus nitrificans DA2 , four strains isolated from the rhizosphere under simulated microgravity conditions. The SynCom exhibited significant potential in promoting plant growth and enhancing plant defense. Our study not only provides insights into plant-rhizosphere microbial symbiosis under simulated microgravity conditions, but also lays the theoretical foundation for the development of soil-based space plant growth systems and engineered microbial communities. [Display omitted] • Simulated microgravity shifted the composition of rhizosphere bacterial communities of wheat. • Rhizosphere recruited beneficial bacteria for microbial equilibrium under simulated microgravity. • Simulated microgravity promoted the reallocation of potential ecological functions in rhizobacteria. • Beneficial rhizobacteria enhanced wheat growth and defense under simulated microgravity. [ABSTRACT FROM AUTHOR]

Space-enclosed cabins such as space stations provide a suitable living environment for astronauts, meanwhile they also facilitate various microorganisms to breed and corrode the materials' surfaces. To effectively prevent and control the microbial contamination in space-closed cabins and ensure the health of the astronauts, it is necessary to develop effective and safe disinfectants. In this study, organosilicon quaternary ammonium salt(OQAS), sodium dehydroacetate (SD) and polyhexamethylene biguanidine hydrochloride(PHMB) were selected as the target disinfectants and tested on four kinds of corrosive fungi, including Cladosporium cladosporioides , Aspergillus niger , Penicillium aurantiogriseum and Cladosporium herbarum. Firstly, the mycelial growth inhibition effects of these three disinfectants on the four fungi were tested separately, and the effective concentration range of the three disinfectants were determined. Then we combined these three disinfectants to get a new highly effective and safe compound bactericides, consisting of OQAS (0.37 mg/ml), SD (0.7 mg/ml) and PHMB (0.5 mg/ml), in which the total concentrations of bactericides were 1.57 mg/ml. This study provided a new perspective for the development of safe microbial bacteriostatic agents in spacecraft. Image 1 • Elucidate the selection principles of disinfectants for the space-enclosed cabins. • Selecting out three potential ideal disinfectants for the space-enclosed cabins. • Development of a compound disinfectant for the space-enclosed cabins. • Providing a new perspective for the development of disinfectants in spacecraft. [ABSTRACT FROM AUTHOR]

Understanding the microbial communities and antibiotic resistance genes (ARGs) in spacecraft assembly cleanrooms is crucial for spacecraft microbial control and astronaut safety. However, there have been few reports of ARG profiles and their relationship with microbiomes in such environments. In the present study, we assessed the bacterial community and ARGs in the air dust and surface environments of a typical spacecraft assembly cleanroom. Our results show a significant difference in bacterial composition between surfaces and air dust, as they belong to two distinct ecostates. Bacillus and Acinetobacter were significantly enriched in the air samples. Bacterial community network analysis revealed lower topological parameters and robustness of bacterial networks in the air samples. We also observed different distribution patterns of some typical ARGs between surface and air dust samples. Notably, the ermB gene exhibited a relatively high copy number and was enriched in the surface environment, compared to that in the air. Overall, our study provides insight into the complex microbial community and the distribution and transfer of ARGs in spacecraft assembly cleanrooms, and offers important input for developing control strategies against ARGs. [Display omitted] • Genera of Bacillus and Acinetobacter were significantly enriched in air samples. • High levels of antibiotic resistance were observed in spacecraft assembly cleanrooms. • Each ARG and MGE were significantly associated with specific bacteria. • More drug-resistant bacterial strains were found in air-dust environments. [ABSTRACT FROM AUTHOR]

Spectral composition of artificial light is an important environmental factor for plants cultivated in controllable environment, eg., plant factory. In an attempt to explore the influence of different spectral wavebands on leaf lettuce growth and development, a new way of light treatment with turning off the specific narrow-wavebands from the wide spectrum was established. And leaf lettuce was cultivated under different light spectra with the spectral wavebands of green (LG), yellow (LY) and purple (LP) “knockout” respectively in controllable environment. Then changes in biomass, morphological indexes, photosynthetic gas exchange, chlorophyll content and soluble sugar content of lettuce were examined. Our results revealed that, compared with plants grown under wide-spectral LED light (CK), LG treatment showed significantly reduction of fresh shoot weight at 25 days after planting (DAP) comparing to CK. LY and LP obtained obviously higher fresh shoot weight and moisture content at 15 DAP, in contrast, significantly lower ratio of root to shoot than CK. And A/Ci in LG were significantly reduced by about 33.3% and 36.1% at 20 DAP and 25 DAP respectively compared with CK. In addition, LY showed significant increases in soluble sugar content compared to other treatments at three sampling stages, while the lowest values were obtained in CK. These results indicated that green, yellow and purple light had significant regulations on the biomass, photosynthesis and soluble sugar content in lettuce, depending on the different growth period. [ABSTRACT FROM AUTHOR]

Under normal gravity conditions, endophytic bacteria, one of the key bacterial community that inhabit in plant tissues, are well-known in promoting the plant growth and health, which are essential for long-term and long-distance manned microgravity space exploration. Here, we report how the Triticum aestivum endophytic bacterial communities behave differently under the simulated microgravity conditions. We demonstrate that, under simulated microgravity conditions, the microbial diversity in wheat seedling leaf increases while that in root decreases, compared to that cultivated under normal gravity conditions. We found that the dominant bacteria genus such as Pseudomonas , Paenibacillus and Bacillus significantly changes with gravity. The findings of this study provide important insight for space research, especially in terms of the Triticum aestivum cultivation in space. [ABSTRACT FROM AUTHOR]

Plant disease control and prevention in microgravity are critical for space plant cultivation. This study investigated the effects of a biocontrol bacterium Pseudochrobactrum kiredjianiae A4 on growth development and antifungal potential of wheat seedlings under simulated microgravity. The growth, antioxidant status and plant immune hormone of both non-infected and infected wheat seedlings were detected before and after inoculation of A4 strains under simulated microgravity condition (μG) and ground condition (1G). Our results showed that bacteria A4 promoted wheat growth by increasing root length and biomass accumulation and meanwhile enhancing fungal disease resistance through improving the antioxidant enzyme activities and plant hormone secretion. Moreover, A4 exhibited a weaker promotion ability on wheat biomass accumulation and disease resistance under μG condition compared to that under 1G. These results not only expand our understanding of the impact of microgravity on plant-microbe interaction, but also provide valuable insights into using plant beneficial microbes for plant cultivation and crop protection in space. [ABSTRACT FROM AUTHOR]

As a consequence of the importance of crop cultivation in Bioregenerative Life Support System (BLSS), there is a necessity of protecting the plants from pathogenic diseases. Cave soil bacteria can be utilized as a source for isolating biocontrol bacteria that are suitable for plant growth in BLSS. Pseudochrobactrum kiredjianiae strain A4 (GenBank accession KT203923) is a gram-positive, short-rod shaped and whitish bacterium isolated from cave soil, and is culturable at 13 °C. A species-level identification was conducted by 16S rRNA gene sequencing, which showed that this strain had a 98% similarity with sequences of P. kiredjianiae isolated from the public domain. The A4 strain was positive for siderophore, indole-3-acetic acid (IAA) production and 1-aminocyclopropane-1-carboxylate (ACC) deaminase activity. The results of in vitro experiments showed that A4 could inhibit the growth and development of Rhizoctonia cerealis , Fusarium graminearumt , Magnaporthe grisea , Fusarium oxysporum and Botrytis cinerea . Under greenhouse conditions, the bacterium A4 improved the physiological parameters and reduced the defense enzymes activities of wheat ( Triticum aestivum L.) in the presence of R. cerealis . Statistical analysis of measured parameters revealed that A4-inoculated wheat plants were positively alleviating pathogenic stress. These results indicate that the isolate A4 provides a promising solution to control plant pathogenic fungi in BLSS. [ABSTRACT FROM AUTHOR]

Light intensity and nitrogen concentration of nutrient solution are considered crucial for the contents of vitamin C and nitrate in cultivated leaf vegetables. We here investigated the effects of various combinations of light intensity (60, 140 and 220 μmol m −2 s −1 ) and nitrogen concentration (7, 15 and 23 mmol L −1 ) of the solution on the growth, photosynthetic characteristics, vitamin C and nitrate content of lettuce. Our results demonstrate that the lettuce had the largest dry biomass at the high illumination of 220 μmol m −2 s −1 and low nitrogen of 7 mmol L −1 . The higher light and low nitrogen also contributed to the accumulation of vitamin C and decrease of nitrate in lettuce leaves. The effect of nitrogen supply on chlorophyll concentrations was more efficient under low light than high illumination. Our results reveal that there was an obvious interaction between light intensity and nitrogen available for the photosynthesis, yield and quality of lettuce. This study provides valuable insights into the combinational regulation of light intensity and nitrogen supply for improving growth and nutritional quality of vegetables grown in greenhouse and plant factory. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is an important cause of death and disability in young people worldwide without effective treatment. Ferroptosis was recently reported to be related to TBI and provided a potential target for developing new therapeutic strategies, but how it influenced TBI and the underlying mechanism were still unclear. Here, with multimodality of methods, ferroptosis was demonstrated to mainly occur in acute TBI. Further, we found that hyaluronic acid (HA), a natural extracellular matrix (ECM) material, could markedly and specifically inhibit ferroptosis in cells and TBI mice. Preblocking the HA-receptor interaction or CRISPR/Cas9-based gene deletion of HA putative receptors neurocan (NCN) and CD44 abolished the anti-ferroptosis effect of HA. Importantly, it was demonstrated that CD44 was significantly up regulated by tens of folds in the focus area of TBI. Through intravenous injection of Cy5-HA nanoconjugates, it was shown that HA could effectively bind to the TBI site like a targeting nanodrug and then, significantly reduced brain damage and behavioral defects. Collectively, we demonstrated HA as the natural anti-ferroptosis material which acted through receptor-mediated intrinsic signaling pathways, and developed a new therapeutic avenue for acute TBI treatment. Moreover, the new function of HA revealed in the study confirmed the existence of extracellular regulation of ferroptosis, and would largely promote the development of novel nanomaterials or nanodrugs for ferroptosis-related tissue injuries. [Display omitted] • Ferroptosis was a key reason for the acute injury and the short therapeutic window of TBI. • Hyaluronic acid (HA) could markedly and specifically inhibit ferroptosis in cells and acute TBI mice. • Neurocan and CD44 were the key receptors mediating the anti-ferroptosis effect of HA. • Cy5-HA nanoconjugates potently target to TBI site like a targeting nanodrug. • HA could be directly used as a targeting nanodrug to reduce the brain damage and behavioral defects after TBI. [ABSTRACT FROM AUTHOR]

Porous-tube nutrient delivery system (PTNDS) allows high control of the root environment and prevents plant infections in both microgravity and ground conditions. In this paper, six soybean cultivars (‘ZH13’, ‘ZH57’, ‘LD10’, ‘HH35’, ‘HH43’, and ‘ZGDD’) were evaluated in terms of yield, photosynthetic efficiency, insoluble dietary fiber and ions uptake efficiency. Besides proximal composition, the concentrations of mineral and isoflavones were monitored in the seeds. ‘HH35’ and ‘ZH13’ plants showed much higher yield and harvest index, in addition to the lower lignin content of inedible biomass. Data showed that ‘HH35’ had the higher photosynthetic efficiency of soybean leaves with regard to photosynthetic rate and instantaneous carboxylation efficiency, whereas chlorophyll ratio and carotenoids content were no difference with the other cultivars. Both cations and anions except NH 4 + and H 2 PO 4 − , were accumulated excessively compared to controls, especially with anions in PTNDS. [ABSTRACT FROM AUTHOR]

Silkworm ( Bombyx mori L.) larvae were used as an ideal animal protein source for astronauts in bioregenerative life support system (BLSS). Here, we compared the differences in bacterial communities of the silkworm larval gut and cellulase-producing and amylase-producing bacteria between the BLSS rearing way (BRW) and the traditional rearing way (TRW) through Illumina Miseq sequencing, culture-dependent approach, 16S rDNA and ITS sequencing, phylogenetic analysis to find the role of gut bacteria in food digestion. The analysis of Miseq showed that the gut microbiota in the BRW was significantly changed than that in the TRW. Results revealed that the isolates can produce cellulose-degrading and starch-degrading enzymes of gut bacteria of silkworm in the BRW which decreased compared with that of the TRW, but the number of isolates both secrete cellulase and amylase are equal. The isolates that can produce both enzymes in the TRW were Alternaria sp. Preussia sp and Coprinellus radians. Meanwhile, in the BRW we found Enterococcus , Erwinia and Pantoea can produce cellulase and amylase. We could use the dominant populations to make probiotic products for nutrient absorption and disease prevention in BLSS to improve gut microecology, as well as the yield and quality of animal protein. [ABSTRACT FROM AUTHOR]

Hydroponic culture has traditionally been used for Bioregenerative Life Support Systems (BLSS) because the optimal environment for roots supports high growth rates. Recent developments in Porous-tube Nutrient Delivery System (PTNDS) also offer high control of the root environment which is designed to provide a means for accurate environmental control and to allow for two-phase flow separation in microgravity. This study compared the effects of PTNDS and traditional hydroponic cultures on biomass yield, nutritional composition and antioxidant defense system (T-AOC, GSH, H 2 O 2 and MDA) of G. bicolor , and ionic concentration (NH 4 + , K + , Mg 2+ , Ca 2+ , NO 3 − , H 2 PO 4 − , SO 4 2 − ) of nutrient solution during planting period in controlled environment chambers. The results indicated that the biomass production and yield of G. bicolor grown in PTNDS were higher than in hydroponic culture, although Relative water content (RWC), leaf length and shoot height were not significantly different. PTNDS cultivation enhanced calories from 139.5 to 182.3 kJ/100 g dry matter, and carbohydrate from 4.8 to 7.3 g/100 g dry matter and reduced the amount of protein from 7.3 to 4.8 g/100 g dry matter and ash from 1.4 to1.0 g/100 g dry matter, compared with hydroponic culture. PTNDS cultivation accumulated the nutrition elements of Ca, Cu, Fe and Zn, and reduced Na concentration. T-AOC and GSH contents were significantly lower in PTNDS than in hydroponic culture in the first harvest. After the first harvest, the contents of MDA and H 2 O 2 were significantly higher in PTNDS than in hydroponic culture. However, the activity of T-AOC and GSH and H 2 O 2 and MDA contents had no significant differences under both cultures after the second and third harvest. Higher concentrations of K + , Mg 2+ and Ca 2+ were found in nutrient solution of plants grown in hydroponics culture compared to PTNDS, wherein lower concentrations of NO 3 − , H 2 PO 4 − and SO 4 2 − occurred. Our results demonstrate that PTNDS culture has more potential to maintain nutritional quality and the optimal root zone environment for G. bicolor compared with hydroponic culture. And further refinements in PTNDS culture would make it a viable alternative for achieving high productivity in a BLSS. [ABSTRACT FROM AUTHOR]

In this work, the effects of different light sources, including high pressure sodium lamp (HPS), T5 fluorescent lamps (T5) and Red–Blue light-emitting diodes (R–B LEDs), on the antioxidant capacity of Gynura bicolor DC were studied through the analysis on the changes of the antioxidant indicators (phenolic compounds, flavonoids, glutathione) and antioxidant activity (DPPH and FRAP) in G. bicolor . The results showed that the highest contents of phenolic compounds and flavonoids were found in G. bicolor under T5, and the antioxidant potential in G. bicolor evaluated by either DPPH or FRAP assay also increased under T5 than others, while the antioxidant activity in G. bicolor under R–B LEDs with narrower spectrum was the lowest under the equal light intensity. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low-light treatment affects physiological and biochemical changes of wheat. [•] Low-light treatment at seedling stage has no significant effect on crop productivity. [•] Low-light treatment at grain filling stage affects final production significantly. [Copyright &y& Elsevier]

Abstract: Biologically processing rice and wheat straws into soil-like substrate (SLS) and then reusing them in plant cultivation system to achieve waste recycle is very crucially important in Bioregenerative life support system (BLSS). However, rice is a plant with strong allelopathic potential. It is not clear yet that what kinds of raw materials can be processed into proper SLS to grow rice in BLSS. Therefore, in this study, the aqueous extract of SLS made from three different materials including rice straw, wheat straw and rice–wheat straw mixture was utilized to investigate its effects on the seed germination and seedling growth of rice. The gradients of the extract concentrations (soil:water) were 1:3, 1:5, 1:9, and 1:15 with deionized water used as control. The effects of different types of SLS on seed germination and seedling vitality of rice were confirmed by analyzing the germination rate, seedling length, root length, the fresh weight and other indicants. In addition, based on the analysis towards pH, organic matter composition and other factors of the SLS as well as the chlorophyll, hormone content of rice, and the mechanism of the inhibition was speculated in order to explore the preventive methods of the phenomenon. Finally, the feasibility of cultivating rice on SLSs made from the raw materials mentioned above was evaluated and wheat raw was determined as the most appropriate material for growing rice. [Copyright &y& Elsevier]

Abstract: Vegetable cultivation plays a crucial role in dietary supplements and psychosocial benefits of the crew during manned space flight. Here we developed a ground-based prototype of horn-type sequential vegetable production facility, named Horn-type Producer (HTP), which was capable of simulating the microgravity effect and the continuous cultivation of leaf–vegetables on root modules. The growth chamber of the facility had a volume of 0.12m3, characterized by a three-stage space expansion with plant growth. The planting surface of 0.154m2 was comprised of six ring-shaped root modules with a fibrous ion-exchange resin substrate. Root modules were fastened to a central porous tube supplying water, and moved forward with plant growth. The total illuminated crop area of 0.567m2 was provided by a combination of red and white light emitting diodes on the internal surfaces. In tests with a 24-h photoperiod, the productivity of the HTP at 0.3kW for lettuce achieved 254.3g eatable biomass per week. Long-term operation of the HTP did not alter vegetable nutrition composition to any great extent. Furthermore, the efficiency of the HTP, based on the Q-criterion, was 7×10−4 g2 m−3 J−1. These results show that the HTP exhibited high productivity, stable quality, and good efficiency in the process of planting lettuce, indicative of an interesting design for space vegetable production. [Copyright &y& Elsevier]

Abstract: Protection of human subjects from microbial contaminants is an important consideration in confined condition. The aim of this study was to investigate whether cruciferous vegetable cultivation will cause microbial contamination of confined living environment. Three cruciferous vegetables including pakchoi (Brassica rapa var. chinensis), lettuce (Lactuca sativa var. longifolia) and Chinese kale (Brassica oleracea var. alboglabra), were separately hydroponically cultivated in encapsulated systems where Sprague-Dawley (SD) rats were used to mimic human. In the control group, SD rats were fed in a parallel encapsulated apparatus without plant cultivation. Surface microbes in all groups were sampled 20 days after the apparatuses were sealed. Microbial burden and community of the samples were analyzed using culture-dependent and culture-independent methods. The results demonstrated that compared with control group, the cultivation of the three cruciferous vegetables effectively decreased microbial burden in the confined system containing rats, among which lettuce displayed the strongest bacteriostasis. PCR-DGGE analysis showed that the microbial community structure varied with the cultivation of three vegetables in the closed system. Phylogenetic analysis suggested that some microbial species were inhibited by the vegetables, including opportunistic human pathogenic bacteria, namely Staphylococcus epidermi, Gemella haemolysans and Enterobacter aerogenes. Overall, the study indicates that the cultivation of pakchoi, lettuce or Chinese kale is effective to reduce microbial burden, and thus the suitable vegetable cultivation in confined environment would not cause microbial contamination, instead, it would reduce microbial health risk. [Copyright &y& Elsevier]

Abstract: To establish an economical and environmentally friendly technology for ethylene removal from horticultural facilities and industrial point sources, a bench-scale natural zeolite biofiltration system was developed in this study. The system was evaluated for its performance in removing ethylene from an artificially contaminated air stream and characterized for its bacterial diversity under varied ethylene concentrations, and in different spatial stages of the filter. The biofilter enabled to approximately 100% remove ethylene at loading rates of 0.26–3.76gm−3 h−1 when operated with inoculum containing enriched ethylene-degrading bacteria. The bacterial diversity and abundance varied with the height of the biofilter. Moreover, the occurrence and predominance of specific bacterial species varied with the concentrations of ethylene introduced into the biofilter, as observed by PCR-DGGE methods. Phylogenetic analysis indicated that the biofilter system supported a diverse community of ethylene-degrading bacteria, with high similarity to species in the classes Betaproteobacteria, Gammaproteobacteria, Bacilli, and Actinobacteria. [ABSTRACT FROM AUTHOR]

CO 2 concentration [CO 2 ] level in artificial ecosystems such as greenhouse agriculture and space farming can easily exceed 1000 μmol mol −1 (or ppm). In order to understand how the growth and development in crop plants may respond to elevated CO 2 , it is necessary to determine if crop leaves in the closed artificial ecosystem have a fully developed photosynthetic apparatus, and whether or not photosynthesis in these leaves is more responsive to elevated CO 2 concentration. To address this issue, we evaluated the response of photosynthetic characteristics, leaf water status and antioxidant capacity of Chufa ( Cyperus esculentus L.), which is a sedge-like plant with 1–2 cm small sweet tubers in length, under elevated CO 2 concentrations in an artificial closed ecosystem. The results showed that Chufa plants cultivated in the elevated CO 2 environment from the seedling stage to the maturity stage were characterized by more appropriate chlorophyll content and photosynthetic rate. The photosynthetic rate of Chufa plants in the 1000 and 3000 ppm treatments was no significant difference with that in 500 ppm CO 2 condition both at seedling stage and rapid growth stage. All the treatments had a high relative water content (RWC) about 60% at the maturity stage. However, there was no significant difference in membrane stability index (MSI) at the rapid growth stage. The antioxidase enzymes activities experienced a rise and a drop and reached the peak at the rapid growth stage. Elevated CO 2 , especially more than 1000 ppm conditions, may accelerant Chufa plants aging process. [ABSTRACT FROM AUTHOR]

This research analyzes a laminated double-curved panel's free/forced vibrational features and Low-Velocity Impact (LVI) Accordingly, the Hertz contact scheme is introduced to model the contact force between the structure and the impactor. Additionally, Hamilton's principle and four-variable refined quasi-3D logarithmic shear deformation theory (RQ-3DLSDT) are accessible for figuring out a structure's motion and Boundary Condition (BC) equations for the LVI. Moreover, for computing the motion equation in the displacement and time frames, respectively, the Galerkin and Newmark methods are provided. Finally, there are two subsections within the results section. The first examines the influence related to the number of laminated layers, the geometry of doubly curved panels, and the ratio associated with Young's module on the indentation and contact force in the time frame. The second discusses the impact of Young's module proportion, the laminated layers' form, and geometrical attributes related to the structure on the present simulation's free and forced vibration features with the LVI. • Forced vibration, and low velocity impact information of the panel. • Galerkin and Newmark procedure are presented for solving the equations. • For modeling the contact force, Hertz contact theory is presented. • When the pattern changes from vertical to horizontal, the instable area and critical curvature factor decrease. • As the Young's modulus ratio decreases, the indentation of the system increases. [ABSTRACT FROM AUTHOR]

Peanut ( Arachis hypogaea L.) has been selected as one of the crop candidates for BLSS, because its seeds have high nutritional value, being rich in vegetable oil and protein. Porous-Tube Nutrient Delivery System (PTNDS) has been successfully used for crop cultivation in controllable environments. In this paper, four peanut cultivars ('HY25', 'HY28', 'HY31' and 'BS1016') were evaluated in terms of yield, photosynthetic efficiency, insoluble fiber and ions uptake efficiency. Besides protein, total oil content and fatty acid composition were monitored in the seeds. 'HY25' plants showed much higher yield and harvest index, in addition to the lower lignin content of inedible biomass. Data showed that 'HY25' had the higher photosynthetic capacity of peanut leaves with regard to highest photosynthetic rate, qP and Φ PSII , lowest energy dissipation ( qN ) values, whereas instantaneous carboxylation efficiency and water use efficiency carotenoids content were no difference with the other cultivars. ‘BS1016′ showed the lowest photosynthetic capacity contrarily. These suggested that ‘HY25′ could be the most suitable for the cultivation in a closed controlled environment with PTNDS. While, both cations and anions except NH 4 + and H 2 PO 4 − , were accumulated excessively compared to controls, especially with anions in PTNDS. Hence, further studies are needed in order to improve the nutritional quality of seeds and modify the fertilization strategy of this cultivar in the growth environment feasible during a closed environment and space mission. [ABSTRACT FROM AUTHOR]

Elevated atmospheric CO 2 has been shown to rapidly alter plant physiology and ecosystem productivity, but contemporary ecological responses to increased CO 2 have yet to be studied in a controlled closed ecosystem with humans. To test this concept, at an integrated ground-based Bioregenerative Life Support System (BLSS) named Lunar Palace-1, we tested elevated CO 2 effects on gas exchange characteristics in an experiment involving humans. During the whole experimental process, researchers monitored CO 2 and O 2 concentrations in different plant growth and human occupied cabins on a real time basis. By turning off lighting and air ventilation system, elevated CO 2 effects were measured in plant chamber and overall facility during a 1 h period. The results indicated that elevated CO 2 had variable effects on plant photosynthetic and respiration rates. Photosynthesis in most plants is typically not saturated with respect to carbon dioxide at 400 ppm. Elevated CO 2 has inhibitory effects on plant respiration. Photosynthesis is strengthened and respiration is reduced in a closed artificial ecosystem were demonstrated under high levels of CO 2 . Our findings in this closed ecosystem may serve as key baseline design data for larger, long-term and higher degree of closure BLSS integration experiment planned for the near future. [ABSTRACT FROM AUTHOR]

As a consequence of the increasing importance of leaf vegetables in Bioregenerative life support system (BLSS), there is an interest in enhancing both the productivity and quality of Gynura bicolor DC ( G. bicolor ). The effects of super-elevated carbon dioxide concentration (3000 ppm) on G. bicolor in different periods were investigated to reveal plausible underlying mechanisms for the growth, photosynthetic characteristics, antioxidant capacity and biomass yield. Experimental results showed that not only the photosynthetic rate but also the antioxidant capacity were increased in short-term super-elevated CO 2 concentration. However, under long-term super-elevated CO 2 concentrations, photosynthetic rate and pigment contents of G. bicolor significantly decreased due to photo inhibition. Elevated CO 2 can be able to dwarf the G. bicolor plants. The leaves in high CO 2 concentration were curled, which may affect the photosynthetic efficiency. At 3000 ppm level, leaf senescence accelerated but biomass yield had no significant difference. Furthermore, elevated CO 2 controlled transpiration rate and then enhanced water use efficiency. Superoxide dismutase (SOD) activity, peroxide activity (POD) and total antioxidant capacity (T-AOC) in 3000 ppm condition were significantly lower than that in 400 ppm condition. On the contrary, catalase (CAT) activity, glutathione (GSH) content and hydrogen peroxide (H 2 O 2 ) were significantly enhanced under high CO 2 concentration. [ABSTRACT FROM AUTHOR]

Wheat ( Triticum aestivum L.) is one of the most important agricultural crops in both space such as Bioregenerative Life Support Systems (BLSS) and urban agriculture fields, and its cultivation is affected by several environmental factors. The objective of this study was to investigate the influences of different environmental conditions (BLSS, plant factory, green house and field) on the wheat growth, thousand kernel weight (TKW), harvest index (HI), biomass yield and quality during their life cycle. The results showed that plant height partially influenced by the interaction effects with environment, and this influence decreased gradually with the plant development. It was found that there was no significant difference between the BLSS and plant factory treatments on yields per square, but the yield of green house and field treatments were both lower. TKW and HI in BLSS and plant factory were larger than those in the green house and field. However, grain protein concentration can be inversely correlated with grain yield. Grain protein concentrations decreased under elevate CO 2 condition and the magnitude of the reductions depended on the prevailing environmental condition. Conditional interaction effects with environment also influenced the components of straw during the mature stage. It indicated that CO 2 enriched environment to some extent was better for inedible biomass degradation and had a significant effect on “source–sink flow” at grain filling stage, which was more beneficial to recycle substances in the processes of the environment regeneration. [ABSTRACT FROM AUTHOR]

Abstract: To establish bioregenerative life support system (BLSS) on lunar or Mars bases in the future, it is necessary to firstly conduct manned simulation experiments, including several different kinds of creatures on the ground. To provide the basis for establishing the system, a multibiological life support system composed of lettuce, silkworm and algae was set up in this study. Lettuce and silkworms were cultivated in a closed integrated cultivating system (CICS) of integrative experimental system (IES). The conveyor-type cultivation method was implemented, which harvested the largest batch of lettuce and silkworms from the system and carried the smallest batch of them into the system every four days. During this process, the main element contents of lettuce were determined. Biomasses, heights, and crown diameters of lettuce in and out of the system were compared. Biomasses, excrement production rates, and bioconversion rates of silkworms in and out of the system were also studied. Results showed silkworms and lettuce in the IES could grow normally. There were no significant differences of biomass, height, or excrement production rates between creatures (lettuce and silkworms) in the system and those out of the system. [Copyright &y& Elsevier]

Abstract Background Asprosin has been identified as a novel hormone enriched in white adipose tissue and is pathologically increased in insulin-resistant mice and humans. However, information regarding the role of asprosin in type 2 diabetes mellitus (T2DM) remains unavailable. Via conducting a hospital-based study, we purposed to ascertain the potential relationship between circulating asprosin concentrations and T2DM. Methods The study recruited 84 adults with T2DM and 86 controls with normal glucose tolerance. They matched in age, body mass index (BMI), and sex. Serum asprosin concentrations were measured via ELISA method. Results Compared to the controls, serum asprosin concentrations were significantly increased in the T2DM adults (P < 0.001). As asprosin concentrations increased across its tertiles, the percentage of T2DM increased (39.28, 37.50, and 70.68%; P value for trend < 0.001). Multivariate logistic regression models demonstrated that compared with the 1st tertile of asprosin, the odds ratio of T2DM was 3.278(95% CI 1.053–10.200, P = 0.040) for the 3rd tertile after adjustment for potential confounders. Area under ROC curve of asprosin (sex and age adjusted) for predicting the presence of T2DM was 0.707[95% CI 0.628–0.786]. Finally, multiple stepwise regression analysis indicated that fasting glucose and triglyceride were independently associated with serum asprosin in T2DM. Conclusions Asprosin concentrations are increased in adults with T2DM. The results suggest that asprosin might serve as a risk factor associated with the pathogenesis of T2DM, but not an ideal biomarker for predicting T2DM. Highlights • Circulating asprosin levels were significantly higher in patients with newly diagnosed T2DM. • As asprosin levels elevated, the risk of having T2DM increased. • Fasting glucose and triglyceride were independently correlated with circulating asprosin. • Insulin secretion and sensitivity indexes were correlated with asprosin, but not independent factors of asprosin. [ABSTRACT FROM AUTHOR]

Minimizing nitrogen (N) consumption and maximizing crop productivity are major challenges to growing plants in Bioregenerative Life Support System (BLSS) for future long-term space mission. Plants cultivated in the controlled environments are sensitive to the low recyclable N (such as from the urine). The purpose of this study is to investigate the effects of nitrogen fertilizer (NH 4 + -N and NO 3 − -N) disturbance on growth, photosynthetic efficiency, antioxidant defence systems and biomass yield and quality of wheat ( Triticum aestivum L.) cultivars during ontogenesis. Experiments were divided into 4 controlled groups,Ⅰ: NO 3 − -N: NH 4 + -N = 7:1 mmol L −1 ; Ⅱ: NO 3 − -N: NH 4 + -N = 14:0.5 mmol L −1 ; Ⅲ: NO 3 − -N: NH 4 + -N = 7:0.5 mmol L −1 and CK: NO 3 − -N: NH 4 + -N = 14:1 mmol L −1 , and other salt concentrations were the same. The results showed that heading and flowering stages in spring wheat are sensitive to low N concentration, especially NO 3 − -N in group Ⅰ and Ⅲ. NO 3 − is better to root growth than to shoot growth. The plants were spindling and the output was lower 21.3% when spring wheat was in low N concentration solution. Meanwhile, photosynthetic rate of low N concentrations is worse than that of CK. The soluble sugar content of the edible part of wheat plants is influenced with NO 3 − : NH 4 + ratio. In addition, when N concentration was lowest in group Ⅲ, the lignin content decreased to 2.58%, which was more beneficial to recycle substances in the processes of the environment regeneration. [ABSTRACT FROM AUTHOR]

A bioregenerative life support system (BLSS) is an artificial closed ecosystem which provides basic human life support for long-duration and far-distance space activities such as lunar bases. “Lunar Palace 1”, an experimental facility, was constructed by our team for the integration research of the key technologies in BLSS, and then a continuous 105-day closed integrative BLSS experiment was carried out in “Lunar Palace 1”(Stage I) successfully last year. In such a system, O 2 produced by higher plants is supplied for the breathing of the crew, as well as the respiration of microorganisms which decompose the solid wastes such as inedible plant biomass and human wastes, while CO 2 produced by the crew and microorganisms is provided for plants to grow. In the system, an excessively high CO 2 level can affect plant growth and may harm human health, however, if the CO 2 level is too low, plant growth may also be inhibited. Thus, keeping the balance between CO 2 and O 2 levels is essential to the gas regulation in the system, and is one of the key points for the operation stability of the system. In this study, an efficient and controllable solid waste bio-convertor was built based on the microbial fermentation in “Lunar Palace 1”, and the CO 2 generation of the bio-convertor under the optimum fermentation conditions in the 105-day airtight experiment was monitored. Moreover, the changes of CO 2 production along with increasing or reducing the temperature of the bio-convertor from 33 to 45 °C (or from 45 to 33 °C) were also investigated, and a positive correlation between the CO 2 output and the fermentation temperature was obtained accordingly. Therefore, the CO 2 production can be adjusted effectively by changing the temperature of the bio-convertor, which implies that it is feasible to regulate the balance between the CO 2 and O 2 concentrations in BLSS by controlling the fermentation conditions of the solid waste treatment unit. The results of this study could lay a foundation for the following researches conducted in “Lunar Palace 1”. [ABSTRACT FROM AUTHOR]

Microbes play a significant role in achieving substance circulation and regeneration in closed artificial ecosystems (CAES) such as bioregenerative life support system (BLSS), greenhouses, and aquaria. In order to understand the pattern of microbial development inside such closed systems, a ground-based closed comprehensive BLSS experimental system named “Lunar Palace 1 (LP1)” was established and a 105-day manned BLSS experiment was carried out in LP1 by our team. During this closed experiment, airborne microbes in the closed cabins of LP1 were sampled and the development and succession law of microorganisms were analyzed using both plate cultivation and molecular biology methods. The results indicated that the dominant bacteria in the air of LP1 were Cupriavidus , Afipia , Delftia , Cyanobacteria and Enterococcus and the dominant fungi were Penicillium , Alternaria , Aspergillus and Cochliobolus , which included not only ubiquitous environmental microorganisms but also opportunistic pathogens. And the succession of dominant microbes’ composition also provided an important experience for solving the problem of microbial contamination in CAES and set a solid foundation for establishing more targeted microbial prevention and control measures in long-term multi-crew closed BLSS experiments in the future. [ABSTRACT FROM AUTHOR]

Rearing of yellow mealworm ( Tenebrio molitor L.) will provide good animal nutrition for astronauts in a bioregenerative life support system. In this study, growth and biomass conversion data of T. molitor larvae were tested for calculating the stoichiometric equation of its growth. Result of a respiratory quotient test proved the validity of the equation. Fiber had the most reduction in mass during T. molitor ′s consumption, and thus it is speculated that fiber is an important factor affecting larval growth of T. molitor . In order to further confirm this hypothesis and find out a proper feed fiber content, T. molitor larvae were fed on diets with 4 levels of fiber. Larval growth, development and respiration in each group were compared and analyzed. Results showed that crude-fiber content of 5% had a significant promoting effect on larvae in early instars, and is beneficial for pupa eclosion. When fed on feed of 5–10% crude-fiber, larvae in later instars reached optimal levels in growth, development and respiration. Therefore, we suggest that crude fiber content in feed can be controlled within 5–10%, and with the consideration of food palatability, a crude fiber of 5% is advisable. [ABSTRACT FROM AUTHOR]

It remains a mystery why the growth rate of bacteria is higher in low-dose ionizing radiation (LDIR) environment than that in normal environment. In this study, a hypothesis composed of environmental selection and competitive exclusion was firstly proposed from observed phenomena, experimental data and microbial ecology. Then a LDIR environment simulator (LDIRES) was built to cultivate a model organism of bacteria, Escherichia coli ( E. coli ) DH5α, the accurate response of bacterial population to ionizing radiation intensity variation was measured experimentally, and then the precise relative dosage of ionizing radiation E. coli DH5α population received was calculated by finite element analysis based on drift-diffusion equations of plasma. Finally, a highly valid mathematical model expressing the relationship between E. coli DH5α population and LDIR intensity was developed by system dynamics based on hypotheses, experimental data and microbial ecology. Both experiment and simulation results clearly showed that the E. coli DH5α individuals with greater specific growth rate and lower substrate consumption coefficient would adapt and survive in LDIR environment and those without such adaptability were finally eliminated under the combined effects of ionizing radiation selection and competitive exclusion. [ABSTRACT FROM AUTHOR]

Plant cultivation plays an important part in deep space manned mission, and the techniques could be used in ground facility agriculture. The screening of strawberry cultivars and a complete cultivation technique for strawberry are necessary in space life support system. In this work, two strawberry cultivars ‘Benihoppe’ and ‘Frandy’ were cultivated under high CO 2 concentration in a closed ecosystem to establish key techniques for strawberry planting for space life support. The main objective of the study is to analyze and evaluate of growth, photosynthetic characteristics, biomass yield and quality of strawberry in a closed ecosystem. Our result showed that the two strawberry cultivars grew well during the 105-day-closed experiment, providing 37.4 g fresh berries every day for the crew in the closed system. The yield, harvest index and sugar content of ‘Frandy’ were comparatively higher than those of ‘Benihoppe’, among which the daily dietary allowance of trace elements and amino acids (18 kinds) in the fruits stood out. This study provided experimental support for the cultivation techniques of berry plants both for life support system and ground facility agriculture, and afforded a new perspective and sufficient information about strawberry cultivation and selection under the special condition of closed ecosystem. [ABSTRACT FROM AUTHOR]

Energy consumption and output are two very important standards for evaluating the reliability of electric light sources when plants are grown in a controlled environment. As a primary source of energy, light is one of the most important environmental factors for wheat growth. The objective of this study was to investigate the influences of light/dark cycle operation with millisecond-scale period on the growth of wheat, photosynthetic characteristics, antioxidant capacity and biomass yield and quality during their life cycle. Four types of intermittent lighting with the same intensity were employed: a light/dark (0.5/0.5 ms) light (50%), a light/dark (0.7/0.3 ms) light (70%), a light/dark (0.8/0.2 ms) light (80%) and a continuous light (100%). The results showed that the wheat cultivated in the 80% light was characterized by highest photosynthetic rate and lowest lignin in inedible biomass, which was more beneficial to recycle substances in the processes of the environment regeneration. The data were comparable to those under continuous light condition in terms of chlorophyll concentration, antioxidant capacity, harvest index (HI) and thousand kernel weight (TKW). Wheat was sensitive to intermittent illumination which significantly affected those indices of growth and physiology, especially at heading and flowering stages. [ABSTRACT FROM AUTHOR]