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PubMedDate not supplied

Microcratering within the lunar regolith--a theory and observation.

Since the Apollo 11 mission to the moon, there has been substantial analysis of the lunar rocks and soil grains, utilizing more recent advances in electron probe technologies. It is the objective of this research to revisit the theories concerning the microcratering within the lunar regolith. Recent theories have included the idea that the microcratering phenomenon was caused by meteoric impacting onto the lunar surface during early lunar history. Other theories have suggested that the microcratering was a result of secondary ejector associated with micrometeoric and meteoric impact. This research team suggests that microcratering may have been associated with primordial dust during and before the formation of our solar system.

Microscopy, Atomic Force↗
PubMed1990

Early diagnosis of Bardet-Biedl syndrome.

A 3-year-old boy presented with decreased renal function, hypertension, obesity and developmental delay. Evaluation of his kidneys revealed blunting of the calyces and multiple renal cortical cysts. Ophthalmologic evaluation showed no abnormalities on examination but electroretinography showed reduced retinal function suggesting a diffuse retinal disorder. Based on the clinical presentation with the associated abnormalities, the diagnosis of Bardet-Biedl syndrome, a form of the Laurence-Moon-Biedl syndrome was made. This syndrome should be considered and specific diagnostic efforts should be made in pediatric patients who present with renal failure and obesity.

Child, Preschool↗
PubMed1990

Impact constraints on the environment for chemical evolution and the continuity of life.

The Moon and the Earth were bombarded heavily by planetesimals and asteroids that were capable of interfering with chemical evolution and the origin of life. In this paper, we explore the frequency of giant terrestrial impacts able to stop prebiotic chemistry in the probable regions of chemical evolution. The limited time available between impacts disruptive to prebiotic chemistry at the time of the oldest evidence of life suggests the need for a rapid process for chemical evolution of life. The classical hypothesis for the origin of life through the slow accumulation of prebiotic reactants in the primordial soup in the entire ocean may not be consistent with constraints imposed by the impact history of Earth. On the other hand, rapid chemical evolution in cloud systems and lakes or other shallow evaporating water bodies would have been possible because reactants could have been concentrated and polymerized rapidly in this environment. Thus, life probably could have originated near the surface between frequent surface sterilizing impacts. There may not have been continuity of life depending on sunlight because there is evidence that life, existing as early as 3.8 Gyr ago, may have been destroyed by giant impacts. The first such organisms on Earth were probably not the ancestors of present life.

Earth, Planet↗
PubMed1990

A patient with features of both Bardet-Biedl and Alström syndromes.

We describe a 30-year-old patient with acanthosis nigricans, diabetes mellitus with insulin resistance, hypogonadotropic hypogonadism, pigmentary degeneration of the retina and cerebellar, pyramidal and posterior columnar involvement. He had normal mental function, normal hearing and no hexadactyly. The patient had symptoms of both Bardet-Biedl and Alström syndromes, but did not manifest all the main features of either syndrome. This suggests either that the Bardet-Biedl, Alström, Laurence-Moon syndromes (including the variant described by Edwards) have a highly variable expression or that our case is a new variant within this group of syndromes.

Acanthosis Nigricans↗
PubMed2003

Appointments at a thyroid outpatient clinic and the lunar cycle.

INTRODUCTION: Several variables of health-related human behaviour have been analysed with regard to a possible association with lunar phases. The aim of this study was to evaluate a possible relation between the lunar cycle and the number of requests for appointments at an outpatient clinic. This variable has not been studied hitherto. METHODS: We analysed a total number of 11,413 requests for appointments at our thyroid outpatient clinic during one year. Access to this clinic is not restricted, and all patients with known or suspected thyroid disease living in the area of Vienna may ask for an appointment. During the study period, 8,852 patients requested a follow-up appointment, and 2561 patients asked for a new appointment. We analysed a possible cyclic pattern in these requests using a nonlinear regression model based on both groups of patients. RESULTS: A cosinus curve with a period of 29.531 days (the mean length of a lunar cycle) was significantly associated with the number of requests for both follow-up appointments (p = 0.007) and new appointments (p = 0.001). Requests for follow-up appointments had their highest peaks three days after the full moon, whereas requests for new appointments were most frequent five days afterwards. CONCLUSION: Our findings suggest that lunar phases may affect patients' requests for appointments at a thyroid outpatient clinic. To the best of our knowledge, this is the first study reporting a possible association between health-related behaviour and lunar phases using requests for appointments as a relevant variable. There is a need for more research into the mechanism underpinning this behaviour.

Appointments and Schedules↗
PubMed1997

An abscisic-acid- and salt-stress-responsive rice cDNA from a novel plant gene family.

A novel cDNA clone osr40cl, encoding a abscisic acid (ABA)-responsive 40-kDa protein previously associated with salt tolerance (Moons et al. '1995' Plant Physiol 107: 177-186), was isolated from roots of rice seedlings (Oryza sativa L.). Exogenously applied ABA and salt shock induced a marked increase of the osr40cl transcript level in roots of seedlings whereas constant osr40cl mRNA levels were found in the shoot. The root-specific salinity-induced osr40cl mRNA accumulation was rapid and gradually declined upon prolonged salt shock. Plant growth regulators, signalling the wounding and the pathogen response, did not enhance osr40cl expression, indicating a salt- and osmotic-stress-specific response. The encoded OSR40cl protein was found to be hydrophilic, rich in histidine residues (6%) constituting putative metal-binding domains, and to consist of a duplicated domain of 151 amino acids (75% identical), that can form amphiphilic alpha-helical structures. The gene osr40cl belongs to a multigene family. Two osr40 genes were isolated, osr40g2 and osr40g3, tandemly arranged in an 8-kb region of the rice genome. Antisera raised against a conserved OSR40 peptide recognized different OSR40 proteins that accumulated in roots upon exposure to salt stress. The OSR40 protein family included 29-KDa proteins and two 40-kDa proteins, the latter most probably corresponding to OSR40cl and OSR40g2 with duplicated domain structures. The osr40g3 transcript encoded a single copy of the OSR40 domain and exhibited a shoot-specific expression. Results indicate that OSR40cl plays a role in the adaptive response of roots to an hyper-osmotic environment and belongs to a novel plant protein family that most probably has structural functions.

Abscisic Acid↗
PubMed2005

Do lunar phases affect conception rates in assisted reproduction?

OBJECTIVES: To assess the effect of the phases of the moon on pregnancy rates in humans following in-vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment. DESIGN: Retrospective, observational study. SETTING: Reproductive Medicine Unit, Liverpool Women's Hospital. PATIENT: Complete data for all women undergoing assisted conception procedures over a period of 13 years (1995-2002). INTERVENTION: Assisted conception procedures--IVF and ICSI. MAIN OUTCOME MEASURES: Biochemical pregnancy that is positive pregnancy test result following embryo transfer. RESULTS: There was no significant effect of any lunar phase on the incidence of biochemical pregnancy (p-value 0.71). Age of the woman significantly affects the chances of pregnancy, (OR 0.95, 95% CI 0.91, 0.998, and p-value 0.04). The chances of pregnancy rises significantly with increase in the number of embryos replaced from 1 to 2 (OR 2.97, CI 1.36, 6.48, and p-value 0.01). CONCLUSION: Pregnancy rates in humans, following assisted conception, appears to be independent of the effect of the lunar phase during which embryo transfer is carried out.

Adult↗
PubMed1976

A new familial syndrome characterized by pigmentary retinopathy, hypogonadism, mental retardation, nerve deafness and glucose intolerance.

Three siblings with retinitis pigmentosa, deafness and mental retardation were studied. Physical abnormalities included nystagmus, acanthosis nigricans and multiple keloids. The two male siblings had gynecomastia, small testes and mild subvirilization whereas the only indication of hypogonadism in the female sibling was oligomenorrhea. Testosterone levels in the males, which were in the low to low normal range, were increased by the administration of large doses of chorionic gonadotropin. The two affected males had elevated plasma luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels which were decreased by the administration of testosterone and increased by the administration of clomiphene. One sibling had mild obesity and diabetes mellitus, one had moderate obesity, normal glucose tolerance and hyperinsulinism and the third had abnormal glucose tolerance and hyperinsulinism. This familial syndrome is distinct from either the Laurence-Moon, Bardet-Biedl or Alström disorders and provides further evidence of genetic heterogeneity in this group of autosomal recessive traits.

Adolescent↗
PubMed1996

A reexamination of amino acids in lunar soils: implications for the survival of exogenous organic material during impact delivery.

Using a sensitive high performance liquid chromatography technique, we have analyzed both the hot water extract and the acid hydrolyzed hot water extract of lunar soil collected during the Apollo 17 mission. Both free amino acids and those derived from acid labile precursors are present at a level of roughly 15 ppb. Based on the D/L amino acid ratios, the free alanine and aspartic acid observed in the hot water extract can be entirely attributed to terrestrial biogenic contamination. However, in the acid labile fraction, precursors which yield amino acids are apparently present in the lunar soil. The amino acid distribution suggests that the precursor is probably solar wind implanted HCN. We have evaluated our results with regard to the meteoritic input of intact organic compounds to the moon based on an upper limit of < or = 0.3 ppb for alpha-aminoisobutyric acid, a non-protein amino acid which does not generally occur in terrestrial organisms and which is not a major amino acid produced from HCN, but which is a predominant amino acid in many carbonaceous chondrites. We find that the survival of exogenous organic compounds during lunar impact is < or = 0.8%. This result represents an example of minimum organic impact survivability. This is an important first step toward a better understanding of similar processes on Earth and on Mars, and their possible contribution to the budget of prebiotic organic compounds on the primitive Earth.

Amino Acids↗
PubMed1991

Lunar base extension program and closed loop life support systems.

Much of papers describing the Lunar Base Construction have been already published. Lunar Base has been considered to be one of the very useful facilities to conduct the excellent scientific program in near future and also to develop the lunar resources such as 3He and oxygen in order to expand the human activities in space. The scale of lunar base and the construction methods to be adopted should be determined based upon the utilization program to be conducted after the initiation of outpost habitation. In order to construct lunar base, it needs to transport lunar base elements such as habitat modules, experiment modules and so on having 20-30 tons weight and to install, connect and activate on lunar surface. The development of transportation system such as OTV enabling to transport over 30 ton payload weight from earth to moon seems to be very difficult in near future, and it seems reasonable to transport three elements per year as described in many papers already published. Therefore, the initial habitat outpost would not have enough volume to produce foods and has to have ECLS system similar to that of space station already going to be developed. After 2-3 years from the initiation of habitation, the addition of food production facilities could be started to expand the habitability of lunar base and finally the complete closed loop life support system could be installed after spending 6-7 years. This paper describes ECLS technologies to be used in the initial habitat outpost and design philosophy of the closed loop technologies to be utilized in the final stage.

Carbon Dioxide↗
PubMed1991

Regenerative life-support system development problems for the Mars mission.

An analysis of expediency of using physicochemical and biotechnological complexes of life-support systems has been performed with reference to the most likely trends of manned cosmonautics development for the nearest decades--orbital stations in the Earth orbit, Moon base, and Mars mission. The analysis results have shown that the physicochemical complex is much more advantageous than the biotechnological one for all cases considered. This conclusion is based on significant difference in power utilization factor: 70-90% for the physicochemical complex and 5-10% for the biotechnological one as far as the photosynthesis efficiency is concerned. The selection of the physicochemical complex systems is considered; particular attention is payed to operating reliability and performance.

Biotechnology↗
PubMed1992

Some challenges in designing a lunar, Martian, or microgravity CELSS.

The design of a bioregenerative life-support system (a Controlled Ecological Life-Support System or CELSS) for long-duration stays on the moon, Mars, or in a space craft poses formidable problems in engineering and in theory. Technological (hardware) problems include: (1) Creation and control of gas composition and pressure, temperature, light, humidity, and air circulation, especially in microgravity to 1/3 xg and in the vacuum of space. Light (energy demanding), CO2 levels, and the rooting media are special problems for plants. (2) Developing specialized equipment for food preparation. (3) Equipment development for waste recycling. (4) Development of computer systems for environmental monitoring and control as well as several other functions. Problems of theory (software) include: (1) Determining crop species and cultivars (some bred especially for CELSS). (2) Optimum environments and growing and harvesting techniques for each crop. (3) Best and most efficient food-preparation techniques and required equipment. (4) Best and most efficient waste-recycling techniques and equipment. This topic includes questions about the extent of closure, resupply, and waste storage. (5) How to achieve long-term stability. (6) How to avoid catastrophic failures--and how to recover from near-catastrophic failures (for example, plant diseases). Many problems must be solved.

Biomass↗
PubMed1992

A study of biohazard protection for farming modules of lunar base CELSS.

For the Closed Ecological Life Support System (CELSS) of a manned lunar base which is planned to be built on the moon early in the 21st century, several proposed programs exist to grow vegetables inside a farming module. At the 40th IAF (Malaga, 1989) the author et al presented a proposal for supplying food and nutrients to a crew of eight members, a basic concept which is based on growing four kinds of vegetables. This paper describes measures for biohazard protection in farming modules. In this study, biohazard protection means prevention of the dispersion of plant diseases to other plant species or other portions of farming beds.

Agriculture↗
PubMed1992

Temperature and humidity control system in a lunar base.

An increasing number of lunar base construction programs are in the process of developing lunar resources such as helium 3. The objective of the present work is to evaluate the temperature and humidity control system, which will allow man to live and work on the moon while developing lunar resources. The results of thermal load calculation show that the load of electric lighting is a 80 to 90% of the cooling load in the habitat module and that only the cooling function is required for temperature control. Due to this, a fluorocarbon refrigerant heat pump system was selected to satisfy reliability, energy consumption, size and weight requirements for the lunar base equipment. According to the load calculation, occupants will feel discomfort due to radiant heat from lighting fixtures. To resolve this problem, an air conditioning system, used in combination with forced convective cooling and panel cooling on the ceiling, was adopted in the living space. Moreover, the experiment on the ground was carried out to evaluate the effects of panel cooling.

Air Conditioning↗
PubMed1992

The cometary contribution to prebiotic chemistry.

Different estimates based on dynamical considerations, lunar cratering rates, Solar System chemical abundances, and the single-impact theory on the origin of the Earth-Moon system suggest that comets and other related small, volatile-rich primitive minor bodies captured by the Earth during the early Archean must have been a major source of volatiles on our planet. It is likely that a substantial fraction of the organic molecules present in the colliding cometary nuclei, which may have included nitrogen bases and the precursors of amino acids, were destroyed due to the high temperatures and shock wave energy associated with the collision. However, the presence of H2O, CN, CH, CO, CO2 and other carbon-bearing molecules and radicals in the atmosphere of the Sun and in circumstellar shells around carbon-rich stars suggests that at least simple carbon species could have survived the cometary collisions. Under the anoxic conditions thought to prevail in the prebiotic terrestrial paleoatmosphere, the post-collisional formation of a large number of excited molecules and radicals, and the rapid quenching of the expanding gaseous ball may have led, upon rapid cooling, to the formation of molecules of biogenic elements and to their eventual deposition in localized environments where complex organic compounds of biochemical significance may have been produced and accumulated.

Carbon↗
PubMed1994

Regenerative life support systems--why do we need them?

Human exploration of the solar system will include missions lasting years at a time. Such missions mandate extensive regeneration of life support consumables with efficient utilization of local planetary resources. As mission durations extend beyond one or two years, regenerable human life support systems which supply food and recycle air, water, and wastes become feasible; resupply of large volumes and masses of food, water, and atmospheric gases become unrealistic. Additionally, reduced dependency on resupply or self sufficiency can be an added benefit to human crews in hostile environments far from the security of Earth. Comparisons of resupply and regeneration will be discussed along with possible scenarios for developing and implementing human life support systems on the Moon and Mars.

Air Conditioning↗
PubMed1994

Heavy-ion induced genetic changes and evolution processes.

On Moon and Mars, there will be more galactic cosmic rays and higher radiation doses than on earth. Our experimental studies showed that heavy ion radiation can effectively cause mutation and chromosome aberrations and that high-LET heavy-ion induced mutants can be irreversible. Chromosome translocations and deletions are common in cells irradiated by heavy particles, and ionizing radiations are effective in causing hyperploidy. The importance of the genetic changes in the evolution of life is an interesting question. Through evolution, there is an increase of DNA content in cells from lower forms of life to higher organisms. The DNA content, however, reached a plateau in vertebrates. By increasing DNA content, there can be an increase of information in the cell. For a given DNA content, the quality of information can be changed by rearranging the DNA. Because radiation can cause hyperploidy, an increase of DNA content in cells, and can induce DNA rearrangement, it is likely that the evolution of life on Mars will be effected by its radiation environment. A simple analysis shows that the radiation level on Mars may cause a mutation frequency comparable to that of the spontaneous mutation rate on Earth. To the extent that mutation plays a role in adaptation, radiation alone on Mars may thus provide sufficient mutation for the evolution of life.

Animals↗
PubMed1987

A constant daylength during the Precambrian era?

The semidiurnal atmospheric thermal tide would have been resonant with free oscillations of the atmosphere when the day was approximately 21 h long, c. 600 Ma ago. Very large atmospheric tides would have resulted, with associated surface pressure oscillations in excess of 10 mbar in the tropics. Near resonance the Sun's gravitational torque on the atmospheric tide--accelerating Earth's rotation--would have been comparable in magnitude to the decelerating lunar torque upon the oceanic tides. The balance of the opposing torques may have long maintained a resonant approximately 21 h day, perhaps for much of the Precambrian. Because the timescale of lunar orbital evolution is not directly affected, a constant daylength would result in fewer days/month. The hypothesis is shown not to conflict with the available (stromatolitic) evidence. Escape from the resonance could have followed a relatively abrupt global warming, such as that occurring at the end of the Precambrian. Alternatively, escape may simply have followed a major increase in the rate of oceanic tidal dissipation, brought about by the changing topography of the world's oceans. We integrate the history of the lunar orbit with and without a sustained resonance, finding that the impact of a sustained resonance on the other orbital parameters of the Earth-Moon system would have not been large.

Atmosphere↗