space sciences and exploration
Fateme Mousavi
Volume 16, Issue 4 , December 2023, , Pages 83-89
Abstract
Seed aging is a process that can lead to a complete loss of seed viability. This process occurs when seeds are exposed to long-term storage or controlled deterioration treatments such as excessive dryness, lack of oxygen, and temperature fluctuations on Earth or in outer space. Proteomic changes can ...
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Seed aging is a process that can lead to a complete loss of seed viability. This process occurs when seeds are exposed to long-term storage or controlled deterioration treatments such as excessive dryness, lack of oxygen, and temperature fluctuations on Earth or in outer space. Proteomic changes can occur in the dry state of seeds. Extreme temperature fluctuations in outer space, especially on the moon and Mars, are one of the most important challenges for space scientists to transfer plant seeds and grow them in outer space outside the atmosphere. The present study studied the effects of simulated space temperature fluctuations on the quantitative and qualitative content of dry tomato seed proteins. The results showed 13 protein bands in the molecular weight range of 8.89 to 91.82 kilodaltons. A double or more significant decrease in the intensity of protein bands with high molecular weight was also observed in the treated group compared to the control. Finally, the two-dimensional electrophoresis technique followed by mass spectrometry is suggested for better resolution of tomato seed proteins and their better separation, as well as identification of unknown protein bands in future studies.
physiology and space medicine (astrobiology)
Fateme Mousavi
Volume 16, English Special Issue , November 2023, , Pages 65-71
Abstract
The extreme temperature fluctuations and the vacuum of the space environment make growing plants in outer space challenging. To simulate the temperature fluctuations and vacuum conditions associated with space environments, dry tomato seeds were placed in a thermal cycle simulator and vacuum simulator ...
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The extreme temperature fluctuations and the vacuum of the space environment make growing plants in outer space challenging. To simulate the temperature fluctuations and vacuum conditions associated with space environments, dry tomato seeds were placed in a thermal cycle simulator and vacuum simulator chamber of space systems, respectively. A Bradford method was used to determine the total protein content of each group of seeds. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis was used to separate proteins. The seed of the thermal cycle group had the highest protein content (26 to 31 mg/ml), followed by control seeds (8-10 mg/ml) and the vacuum seeds (4-5.6 mg/ml). The molecular weights of the peptides ranged from 8 to 42 kDa. The intensity of the protein bands was significantly different in the thermal cycle group from the other two groups, and vacuum group had the lowest intensity. Water and oil released from seeds in the vacuum environment resulted in a reduction of protein content. In the thermal cycle group, the total protein content and the intensity of the bands were significantly higher than those treated with the control group, which can be attributed to the degradation of storage proteins involved in seed germination in the control group.
Space New Technologies
Hassan Naseh; Mostafa Jafarpanah
Volume 15, Issue 3 , September 2022, , Pages 79-92
Abstract
The purpose of this paper is to present the cost estimation and optimization of space propulsion systems. Thus, choosing optimal propulsion system (from fuel and oxidizer aspect) is done in order to increase the efficiency and decrease the cost. Also, human resource cost and technology development time ...
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The purpose of this paper is to present the cost estimation and optimization of space propulsion systems. Thus, choosing optimal propulsion system (from fuel and oxidizer aspect) is done in order to increase the efficiency and decrease the cost. Also, human resource cost and technology development time based on the consideration of labor cost effect on the personals motivation have been optimized. To this end, cost estimation and optimization algorithm has been drawn and suggested. The suggested algorithm has two steps. The first step in the algorithm is concern to cost estimation for seven fuel and oxidizer components. In the second step, labor cost and project implementation time is estimated and optimized based on the optimal space propulsion system derived from the previous step. Here, the objective functions are propulsion system technology development cost and time. On the other hand, the purpose is to consider the salary enhancement and consequently efficiency enhancement, time decrease and cost decrease.