Mineral catalysis of the formation of the phosphodiester bond in aqueous solution: the possible role of montmorillonite clays.

The binding of adenosine to Na(+)-montmorillonite 22A is greater than 5'-AMP, at neutral pH. Adenine derivatives bind more strongly to the clay than the corresponding uracil derivatives. These data are consistent with the protonation of the adenine by the acidic clay surface and a cationic binding of the protonated ring to the anionic clay surface. Other forces must be operative in the binding of uracil derivatives to the clay since the uracil ring system is not basic. The reaction of the 5'-AMP with water soluble carbodiimide in the presence of Na(+)-montmorillonite results in the formation of 2',5'-pApA (18.9%), 3',5'-pApA (11%), and AppA (4.8%). When poly(U) is used in place of the clay the product yields are 2',5'-pApA (15.5%), 3',5'-pApA (3.7%) and AppA (14.9%). The cyclic nucleotide, c(pA)2 is also formed when poly(U) is used. AppA is the principal reaction product when neither clay nor poly(U) is present in the reaction mixture. When 2'-deoxy-5'-AMP reacts with carbodiimide in the presence of Na(+)-montmorillonite 22A the products are dpApA (4.8%), dAppApA (4.5%) and dAppA (17.4%). Cyclic 3',5'-dAMP is the main product (14%) of the reaction of 2'-deoxy-3'-AMP.     

Chemical evolution of RNA under hydrothermal conditions and the role of thermal copolymers of amino acids for the prebiotic degradation and formation of RNA.

The roles of thermal copolymers of amino acids (TCAA) were studied for the prebiotic degradation of RNA. A weak catalytic ability of TCAA consisted of Glu, L-Ala, L-Val, L-Glu, L-Asp, and optionally L-His was detected for the cleavage of the ribose phosphodiester bond of a tetranucleotide (5'-dCrCdGdG) in aqueous solution at 80 degees C. The rate constants of the disappearance of 5'-dCrCdGdG were determined in aqueous solutions using different pH buffer and TCAA. The degradation rates were enhanced 1.3-3.0 times in the presence of TCAA at pH 7.5 and 8.0 at 80 degrees C, while the hydrolysis of oligoguanylate (oligo(G)) was accelerated about 1.6 times at pH 8.0. A weak inhibitory activity for the cleavage of oligo(G) was detected in the presence of 0.055 M TCAA-Std. On the other hand, our recent study on the influences of TCAA for the template-directed reaction of oligo(G) on a polycytidylic acid template showed that TCAA has an acceleration activity for the degradation of the activated nucleotide monomer and an acceleration activity for the formation of G5' ppG capped oligo(G). This series of studies suggest that efficient and selective catalytic or inhibitory activities for either the degradation or formation of RNA under hydrothermal conditions could have hardly emerged from the simple thermal condensation products of amino acids. A scenario is going to be deduced on the chemical evolution of enzymatic activities and RNA molecules concerning hydrothermal earth conditions.     

Evidence for large organic molecules in the diffuse medium using optical high resolution spectroscopy.

The Diffuse Interstellar Bands (DIBs) are absorption lines observed in the line of sight toward reddened OB stars. Their ubiquitous detection in space indicates chemically stable and abundant carriers. High resolution spectroscopy led to the detection of substructures in the line profiles of a few DIBs, indicating a gas phase molecular origin of the carriers. Line profile studies are useful tools to derive information on the band carriers nature. In this paper we compared the velocity structure of the lambda 6613 angstroms DIB line profile to the NaD1 and CaII profiles toward 6 targets of the Perseus OB2 association.     

Quenched Carbonaceous Composite: a laboratory analog for carbonaceous material in the interstellar medium.

We review the properties of Quenched Carbonaceous Composite (QCC), a residue produced from a hydrocarbon plasma, and the properties of its derivatives. A. Sakata and his colleagues have shown that QCC has a 220 nm absorption band, visible fluorescence matching the extended red emission seen in reflection nebulae, and infrared absorption bands that correspond to the infrared emission features in reflection nebulae, HII regions, and planetary nebulae. These properties make QCC a strong candidate material as a laboratory analog to the carbonaceous material in the interstellar medium. QCC is distinguished from the PAH hypothesis in that (1) it is a condensate composed of aromatic and aliphatic molecules, as well as radicals; (2) it exhibits a 220 nm absorption that is very similar in wavelength to the 217 nm absorption in the interstellar medium; (3) it exhibits visible fluorescence consistent with that seen in reflection nebulae; and (4) the bands at 7.7 and 8.6 microns are caused by ketone bands in oxidized QCC. The aromatic component in QCC is thought to be typically 1-4 rings, with the majority being about 1-2 rings.     

A direct approach to the study of the effect of gravity on axis formation in birds.

A system has been developed to enable the normal development of aborted very early uterine avian embryos, outside the female's uterus. The shell-less aborted egg was put into a foster shell of a sister egg, previously laid by the same female. The empty space between the shell and aborted egg was filled with artificial uterine fluid. The reconstructed eggs were incubated at 42 degrees C for 30 hours in a vertical position. The atmosphere contained a high concentration of CO2 (8-10%). At the termination of the 30 h the eggs were transferred to incubation at 37 degrees C in normal atmospheric conditions. Normal development has been recorded for a certain percentage of eggs incubated up to 12 days. In other cases abnormalities, arrested development or development of extraembryonic membranes only, without a sign of an embryonic axis, have been observed. The three important conclusions from the above experiments were: 1. It is possible to develop a closed, self-contained system, disconnected from the female's body, that would support the development of early uterine embryos. 2. The incidence of embryo-less extraembryonic membranes in such a system, is correlated with the degree of detachment of the "yolk" from the outer envelopes. 3. Such a system can be further developed into an experiment suited for microgravity conditions which will be an alternative to an experiment with live birds. The experiment will be aimed at testing the importance of gravity in changing the radially symmetrical avian blastoderm into a bilaterally symmetrical blastoderm.     

Origins of amino acids in the early solar system.

Synthesis of meteoritic amino acids probably took place in the aqueous sub-surface regions of one or more asteroid-sized parent bodies. Starting material for those reactions apparently consisted of a population of more simple compounds including a suite of aliphatic precursors characterised by (1) complete structural diversity, (2) prevalence of branched- over straight-chain species, (3) exponential decrease in abundance with increasing C number, (4) large enrichment in D, and, probably, (5) systematic decrease in 13C/12C with increasing C number. Those properties were apparently acquired during synthesis of the precursors by ion-molecule reactions in a presolar molecular cloud.     

A mathematical model of plants-microorganisms interaction on complete mineral medium and under nitrogen limitation.

A mathematical model concerning the interaction of plants and rhizospheric microorganisms on complete mineral medium and under nitrogen limitation has been constructed. The model takes into account the closeness of plants and microorganisms in terms of the matter released by the plant and consumed by the microorganisms. The effect of rhizospheric microorganisms on plant growth with normal carbon dioxide and complete mineral medium has been demonstrated. Plants interacting with microorganisms have a greater biomass than plants growing without microorganisms. Wheat growth stimulation by metabolites of rhizospheric microorganisms under laboratory conditions on artificial soil has been experimentally demonstrated (Pechurkin, 1997). Under nitrogen limitation, the biomass of plants, with or without microorganisms, is identical, and is substantially reduced as compared with the medium with standard nitrogen.     

Creation of biological module for self-regulating ecological system by the way of polymerization of composite materials in free space.

The large-size frame of space ship and space station can be created with the use of the technology of the polymerization of fiber-filled composites and a liquid reactionable matrix applied in free space or on the other space body when the space ship or space station will be used during a long period of time. For the polymerization of the station frame the fabric impregnated with a long-life polymer matrix (prepreg) is prepared in terrestrial conditions and, after folding, can be shipped in a compact container to orbit and kept folded on board the station. In due time the prepreg is carried out into free space and unfolded. Then a reaction of matrix polymerization starts. After reaction of polymerization the durable frame is ready for exploitation. After that, the frame can be filled out with air, the apparatus and life support systems. The technology can be used for creation of biological frame as element of self regulating ecological system, and for creation of technological frame which can be used for a production of new materials on Earth orbit in microgravity conditions and on other space bodies (Mars, Moon, asteroids) for unique high price mineral extraction. Based on such technology a future space base on Earth orbit with volume of 10(6) m3 and a crew of 100 astronauts is considered.     

Modelling of the new formation structures in the near space.

Complex numerical model of young meteor stream formation taking into account reactive deceleration of cometary nucleus and its form change in the process of stream formation is discussed. The model made it possible to predict the existence of fine and superfine structures for young meteor streams, the characteristics of which agree with the observational data on the Draconid and Leonid meteor showers.     

Methods for measurement and control of leakage in CELSS and their application and performance in the Biosphere 2 facility.

Atmospheric leakage between a CELSS and its surround is driven by the differential pressure between the two. In an earth-based CELSS, both negative and positive differential pressures of atmosphere are created as the resultant of three influences: thermal expansion/contraction, transition of water between liquid and vapor phases, and external barometric pressure variations. The resultant may typically be on the order of 5000 pascals. By providing a flexible expansion chamber, the differential pressure range can be reduced two, or even three, orders of magnitude, which correspondingly reduces the leakage. The expansion chamber itself can also be used to measure the leak rate. Independent confirmation is possible by measurement of the progressive dilution of a trace gas. These methods as employed at the Biosphere 2 facility have resulted in an estimated atmospheric leak rate of less than 10 percent per year.     

A role of cytoskeletal structure of cortical cells in the gravity-regulated formation of a peg in cucumber seedlings.

Seedlings of cucurbitaceous plants develop a protuberant tissue, or peg, on the lower side of the transition region between root and hypocotyl when germinated in a horizontal position. Peg develops due to a change in growth polarity of the cortical cells. We have examined the role of the cytoskeletal structure in peg formation of cucumber seedlings. We observed that in both peg and normal cortical cells of 36 h-old seedlings the microtubules (MTs) were arranged perpendicular to the longitudinal axis of the elongating cells. Application of colchicine perturbed the MTs structure and inhibited the formation of pegs. In 20 h-old seedlings, MTs in cortical cells destined to be a peg tissue had no preferential organization, whereas MTs in normal cortical cells were transversely oriented. After 24 h, the MTs in future peg cells were arranged similar to those of 36 h-old seedlings, although the initiation of peg tissue was not yet visible. These results suggest that reorganization of MTs is required for peg formation and causes the change in growth polarity of the cortical cells.     

Propagation of normal and faster CMEs in the interplanetary medium

We have analyzed 101 Coronal Mass Ejection (CME) events and their associated interplanetary CMEs (ICMEs) and interplanetary (IP) shocks observed during the period 1997–2005 from the list given by Mujiber Rahman et al. (2012). The aim of the present work is to correlate the interplanetary parameters such as, the speeds of IP shocks and ICMEs, CME transit time and their relation with CME parameters near the Sun. Mainly, a group of 10 faster CME events (V_INT > 2200 km/s) are compared with a list of 91 normal events of Manoharan et al. (2004). From the distribution diagrams of CME, ICME and IP shock speeds, we note that a large number of events tends to narrow towards the ambient (i.e., background) solar wind speed (∼500 km/s) in agreement with the literature. Also, we found that the IP shock speed and the average ICME speed measured at 1 AU are well correlated. In addition, the IP shock speed is found to be slightly higher than the ICME speed. While the normal events show CME travel time in the range of ∼40–80 h with a mean value of 65 h, the faster events have lower transit time with a mean value of 40 h. The effect of solar wind drag is studied using the correlation of CME acceleration with interplanetary (IP) acceleration and with other parameters of ICMEs. While the mean acceleration values of normal and faster CMEs in the LASCO FOV are 1 m/s², 18 m/s², they are −1.5 m/s² and −14 m/s² in the interplanetary medium, respectively. The relation between CME speed and IP acceleration for normal and faster events are found to agree with that of  and  except slight deviations for the faster events. It is also seen that the faster events with less travel time face higher negative acceleration (>−10 m/s²) in the interplanetary medium up to 1 AU.     

Optimization of moisture content for wheat seedling germination in a cellulose acetate medium for a space flight experiment.

The Porous Tube Plant Nutrient Delivery System (PTPNDS), a hydrophilic, microporous ceramic tube hydroponic system designed for microgravity, will be tested in a middeck locker of the Space Shuttle. The flight experiment will focus on hardware operation and assess its ability to support seed germination and early seedling growth in microgravity. The water controlling system of the PTPNDS hardware has been successfully tested during the parabolic flight of the KC-135. One challenge to the development of the space flight experiment was to devise a method of holding seeds to the cylindrical porous tube. The seed-holder must provide water and air to the seed, absorb water from the porous tube, withstand sterilization, provide a clear path for shoots and roots to emerge, and be composed of flight qualified materials. In preparation for the flight experiment, a wheat seed-holder has been designed that utilizes a cellulose acetate plug to facilitate imbibition and to hold the wheat seeds in contact with the porous tube in the correct orientation during the vibration of launch and the microgravity environment of orbit. Germination and growth studies with wheat at a range of temperatures showed that optimal moisture was 78% (by weight) in the cellulose acetate seed holders. These and other design considerations are discussed.     

Direct interaction between amino acids and nucleotides as a possible physicochemical basis for the origin of the genetic code.

A study of the association of homocodonic amino acids and selected heterocodonic amino acids with selected nucleotides in aqueous solution was undertaken to examine a possible physical basis for the origin of codon assignments. These interactions were studied using 1H nuclear magnetic resonance spectroscopy (NMR). Association constants for the various interactions were determined by fitting the changes in the chemical shifts of the anomeric and ring protons of the nucleoside moieties as a function of amino acid concentration to an isotherm which described the binding interaction. The strongest association of all homocodonic amino acids were with their respective anticodonic nucleotide sequences. The strength of association was seen to increase with increase in the chain length of the anticodonic nucleotide. The association of these amino acids with different phosphate esters of nucleotides suggests that a definite isomeric structure is required for association with a specified amino acid; the 5'-mononucleotides and (3'-5')-linked dinucleotides are the favored geometries for strong associations. Use of heterocodonic amino acids and nonprotein amino acids supports these findings. We conclude that there is at least a physicochemical, anticodonic contribution to the origin of the genetic code.     

Simultaneous dual wavelength observations of an impulsive microwave burst using the V.L.A.

Simultaneous observations of a microwave burst at 2 and 6 cm wavelengths were carried out with the Very Large Array (VLA). The 6 cm burst source is located close to a magnetic neutral line, presumably near the top of a flaring loop, while the 2 cm emission originates from the footpoints of the loop. It is concluded that the 6 cm emission is dominated by gyrosynchrotron radiation of the thermal electrons in the bulk heated plasma at a temperature of ～ 4 × 10⁷ K, while the 2 cm emission is due to nonthermal particles released and accelerated during the flare process. From the observed low degree of polarization and the lack of the 2 cm source cospatiality with the 6 cm source a magnetic field of 200–350 G and δ ? 4 are estimated in the flare energy release site. A DC electric field flare model is invoked to explain the long delay between the peaks at the two wavelengths. From the delay, the strength of the electric field is estimated to be 0.2–4 μ statvolt cm^?1 in the flaring region.     

Development of space-fertilized eggs and formation of primordial germ cells in the embryos of Medaka fish.

In the second International Microgravity Laboratory (IML-2) mission in 1994, four small Japanese killifish (Medaka, Oryzias latipes) made a space travel of 15 days aboard a space shuttle. These four adult Medaka fish successfully mated in space for the first time among vertebrate animals. Moreover, the eggs they laid developed normally, at least in their external appearance, hatching as fry (baby fish) in space. Fish mated and laid eggs every day during the first week. Near the end of the mission most of the eggs had a well-developed body with two pigmented eyes. In total, 43 eggs were laid (detected), out of which 8 fry hatched in space, as truly 'space-originated' babies. A further 30 fry hatched within 3 days after landing. This is the normal hatching rate, compared with the ground-based data. Among the 8 space-originated fry, four were killed for histological sections, and germ cells at the gonadal region were counted for each fry. Their numbers were in the range of the germ cells of the normal control fry (ground-kept samples). Thus, as embryos developed normally in their external appearance, inside the embryos the formation of primordial germ cells took place normally in space, and their migration to the genital ridges was not hindered by microgravity. The two of the remaining space-originated fry have grown up and been creating their offspring in the laboratory. This proved that the primordial germ cells formed in space were also normal from a functional point of view. The four space-travelled adult fish re-started mating and laying eggs on the 7th day after landing and continued to do so every day afterward. Fertilization rate and hatchability of these eggs were as high as the eggs laid by the laboratory-kept fish. This fact implies that in gametogenesis of adult fish, there are no specific stages of germ cells extremely susceptible to microgravity.     

Structure of high-molecular carbonaceous compound in carbonaceous chondrites and formation of IR-spectroscopically similar compounds in the laboratory.

Main components of carbonaceous matter in carbonaceous chondrites are high molecular organic matter. Examinations of the compounds using pyrolysis GC/MS and FT-IR indicated the structural resemblance of major part of the molecule for all of the compounds from different types of carbonaceous chondrites (8 Antarctic and 2 none-Antarctic meteorites). A carbonaceous matter derived from graphite on a shock experiment using a rail gun (1g projectile at 7 km/s) showed similar IR spectrum to those of the meteoritic high-molecular organic matter. C-60 fullerene also gave a similar compound (with minor differences in IR spectra) on a shock experiment under the same conditions. A shock experiment using coronene also examined.     

The magnetospheres of Jupiter and Saturn and their lessons for the Earth

The study of planetary magnetospheres allows us to understand processes occurring in the Earth’s magnetosphere by showing us how these processes respond under different conditions. We illustrate lessons learned about the control of the size of the magnetosphere by the dynamic pressure of the solar wind; how cold plasma is lost from magnetospheres; how free energy is generated to produce ion cyclotron waves; the role of fast neutrals in a planetary magnetosphere; the interchange instability; and reconnection in a magnetodisk. Not all information flow is from Jupiter and Saturn to Earth; some flows the other way.     

Overwintering in the Antarctica as an analog for long term manned spaceflight.

As a part of Polar Psychological Project planned by SCAR group on Antarctic-Space-Related-Human-Factors-Research, a series of psychological tests were conducted on the Japanese wintering-over personnel. The main purpose of the research was to study the behavioral characteristics, such as depression, insomnia, anxiety, and hostility, which might develop during the course of wintering-over period, and it involves a detailed study of the individuals and interpersonal relationship.     

Bone metabolism and formation of mice bred in a 2 G environment.

The purpose of this study is to reveal the effect of chronic hypergravity exposure on the bone formation and the bone metabolism when mammals produce offspring in a 2 G environment. We measured the length and width of the thighbone, the length of the pelvis, the width of the pelvic cavity and the width of the fourth cervical vertebra on the second (F2) and the third (F3) generation mice bred in a 2 G environment every ten days from 20 days old to 60 days old in an experiment on bone formation. In an experiment on bone metabolism, we measured calcium and phosphorus in the bones of the F3 in the 2 G group. Ratios of the thighbone length, pelvis length, pelvic cavity width, and fourth cervical vertebra width versus the body length were calculated. These ratios were higher in the 2 G group than the control group during all measuring periods. Calcium and phosphorus concentrations in the thighbone and the lumbar vertebra were lower in the 2 G group than in the control group. However, the calcium and phosphorus concentrations in the cervical vertebrae of the 2G group were higher. These results suggest that the influence of gravity load may vary in the bones.