Human Physiological Responses to the G-Load Accompanying the Orbiting and Descent of Soyuz Spacecraft

Data accumulated over 25 years (from 1975 to 2000) on cosmonaut physiological reactions, subjective sensations, and general resistance to G-loads accompanying the orbiting, descent, and landing of Soyuz spacecraft during actual spaceflights are summarized. Materials on short-term (shorter than one month) and long-term (longer than one month) missions in which cosmonauts used or did not use means of preventing microgravity effects during the flight and an anti-G suit (AGS) during descent are analyzed. The physiological reactions of cosmonauts during real spaceflights and terrestrial studies using a centrifuge are compared taking into account cosmonaut ages (from 31 to 55 years). The strain on physiological systems and the reserves of the body upon exposure to +Gxregimens is estimated. A distinct trend toward a lower resistance to descent G-load (without an AGS) with an increase in the time spent in microgravity is found even in the cases when means of prevention of microgravity effects were used. The necessity of using an AGS during descent, irrespective of the flight duration, is demonstrated. The results obtained enable the resistance of cosmonauts to standard G-load conditions during real spaceflights to be predicted.     

An isoenzyme marker linked to the incompatibility locus in cherry

Analysis of two cherry progenies from semi-compatible crosses for the esterase enzyme system showed extremely distorted segregation ratios for Est-5. Analysis of two progenies from compatible crosses for esterase and for stylar ribonuclease proved that Est-5 is linked with the incompatibility locus S. The recombination fraction is 4%. About a fifth of some 50 cultivars or selections genotyped for Est-5 were heterozygous. The various heterozygotes could provide ’testers’ for the presence in cultivars of unknown genotype of 8 of the 11 known S alleles. A seedling suitable for testing S ₉ has been identified and crosses have been made to raise testers for S ₁₀ and S ₁₁ . Isoenzyme analysis of the four progenies for glutamate oxaloacetate transaminase, and of one of them for isocitrate dehydrogenase, showed no evidence for the linkage of Got-1 or Idh-2 with S, contrary to a previous report. Estimation of linkage with S in semi-compatible crosses is discussed. Received: 16 April 1999 / Accepted: 22 June 1999     

Synopsis of scientific results of the sarec sponsored project on the ecology of Lake Kariba

A summary of current research on Lake Kariba is given. Lake Kariba is now a phosphorus limited oligotrophic lake, dependent on annual nutrient input for the maintenance of production. Nitrogen fixation by cyanobacteria has become an important source of nitrogen in the dry season and that fish harvesting is an important phosphorus sink. An up to date plankton composition list has been produced and plankton biomass determined. Diving studies indicate large biomass of bivalves. The aquatic vegetation displays both longitudinal as well as depth gradients, related to light regimes. Only preliminary data are available on mud/water interactions, but the available data indicate considerable fluxes in the river mouth stations and shallow protected littoral areas. The role of predatory birds and crocodiles in the fishery economy of the lake is evaluated and indicates no major conflict between these predators and human fishing interests. The research also draws attention to pesticides in Lake Kariba as indicated by work on fish eating birds and crocodile research. Since the publication of ‘Lake Kariba’ by Balon & Coche (1975) the research project, THE ECOLOGY OF LAKE KARIBA, being undertaken by the University Lake Kariba Research Station constitutes the first multidisciplinary study of the lake, 30 years after the Zambezi river was impounded at Kariba Gorge. It could have offered a unique opportunity of comparing the lake now with what it was soon after impoundment.     

An experiment with a 105-day isolation simulating some conditions of a space flight to mars: the goals, scope, and structure of the research

The article deals with the main goals, objectives, and features of a 105-day experiment simulating some conditions of a manned space flight to Mars. It contains the scope and time patterns of the research program of the 105-day experiment, as well as methodological and organizational recommendations for the preparation for a 520-day experiment based on the analysis of the results of a 105-day experiment.     

Ten years after medaka fish mated and laid eggs in space and further preparation for the life-cycle experiment on ISS.

In the second International Microgravity Laboratory (IML-2/STS-65) mission in 1994, medaka fish (Oryzias latipes) performed their successful mating behavior in space for the first time among vertebrate animals. The eggs the fish laid in space developed normally, and hatched as fry (baby fish) in space. Those fry born in space had the same number of germ cells as the ground control fish, and these germ cells later developed to produce the offspring on the ground. Fry hatched in space did not exhibit any looping behavior regardless of their strain, visual acuity, etc. For fish, one of the most exciting experiments to be done abroad the International Space Station (ISS) is a realization of fish life cycles in microgravity. At present, fish are the most likely candidates to be the first vertebrate to live their life cycle in space. Research done in our laboratory for realizing the life-cycle experiment of medaka fish are also introduced.     

An experiment illustrating the effect of immobilisation on enzyme properties

The experiment described in this paper introduce to students to immobilisation of β-glucosidase, induced in Aspergillus niger cultures, by entrapment method in calcium alginate gel. Additionally, the determination of apparent kinetic parameters, the pH/enzyme activity curves and the study of the thermal stability permits students to check and understand the effect of the immobilisation on the properties of the enzyme.     

Comparison of the performance of Cicadulina leafhoppers on flight mills with that to be expected in free flight

Flight mills are commonly used to assess the relative flight performance of migratory insects, but uncertainties about the rate of energy expenditure on the mill mean that absolute estimates of flight endurance are not usually attempted. In this paper we describe how we measured the power delivered to a lightweight flight mill by tethered Cicadulina storeyi China leafhoppers (Homoptera: Cicadellidae), and compared this to estimates of the power they use to maintain free flight. Our results showed that the leafhoppers were generating more than 0.90 W of mechanical power when on the mill, and that they probably have 3–4 W available for free flight. We conclude that whilst flying on the mill, the insects were generating at least 20–30% of the mechanical power needed for free flight, and that this percentage may have been significantly higher.     

An introduction to the Freshwater Animal Diversity Assessment (FADA) project

The Freshwater Animal Diversity Assessment (FADA) project aims at compiling an overview of genus- and species-level diversity of animals in the continental, aquatic ecosystems of the world. It is a collective effort of 163 experts, and presents 59 articles treating the diversity and endemism of different animal taxa, ranging from microscopic worms to mammals, at global and regional scales. Given their structural importance, an article on macrophytes is also added. Here, we give an overview of the project’s history, and outline the common framework of the various articles, as well as the conventions the experts agreed to adhere to in their treatises. Furthermore, we briefly introduce future prospects.

对“果酒和果醋的制作”实验的改进

按照课程标准的要求．组织学生实施了人教版普通高中课程标准实验教科书生物选修1专题1课题1实验“果酒和果醋的制作”,实验过程中,对如何搞好该实验进行了探究和改进．取得良好的效果。     

The influence of flight on the phospholipid metabolism in insect flight muscle

Males of the American cockroach, Periplaneta americana, received an injection of 32P-orthophosphates and the specific activity of phosphatidylcholine (PC), phosphatidylethanolamine (PE) and phosphatidylinositol (PI) was determined after 120 min of in vivo incorporation. If the insects were forced to fly for 10 min immediately before the end of the experiment, the specific activity (S.A.) of PC and PE was lowered by 34.3 and 31.0%, respectively, that of PI by 17.5%. If the animals were allowed to rest for 10 min after cessation of flight, the S.A. of PC and PE did not differ significantly from the controls, whereas that of PI rose by 91.0% above the control value. These effects cannot be due to changes in precursor labelling (glycerophosphate and phosphoarginine were measured) and reflect changes in the rate of phospholipid biosynthesis. The possibility is discussed that mechanisms regulating the rate of phospholipid biosynthesis are involved.     

An economic experiment reveals that humans prefer pool punishment to maintain the commons

Punishment can stabilize costly cooperation and ensure the success of a common project that is threatened by free-riders. Punishment mechanisms can be classified into pool punishment, where the punishment act is carried out by a paid third party, (e.g. a police system or a sheriff), and peer punishment, where the punishment act is carried out by peers. Which punishment mechanism is preferred when both are concurrently available within a society? In an economic experiment, we show that the majority of subjects choose pool punishment, despite being costly even in the absence of defectors, when second-order free-riders, cooperators that do not punish, are also punished. Pool punishers are mutually enforcing their support for the punishment organization, stably trapping each other. Our experimental results show how organized punishment could have displaced individual punishment in human societies.