Correlation of biophysical parameters of biologically active points and variations of heliogeophysical factors

The correlation between the parameters of biologically active points and the dynamics of solar activity was studied. Statistically significant correlations between electroconductivity of biologically active points and solar activity indices (sunspot number, Ap-index, solar radiowave flux) were revealed. The spectral analysis of the temporal organization of biologically active points revealed a set of periods present in the dynamics of solar activity. It was concluded that bioelectric system of the human organism is a complicated multilevel time-structure, which effectively reacts to changes in heliogeophysical dynamics. The bioelectric system of biologically active points is considered to be one of general information channels of electromagnetic nature, which realize the connection of organism with environment.     

Intraocular pressure (IOP) in relation to four levels of daily geomagnetic and extreme yearly solar activity

The link between geomagnetic field activity (GMA), solar activity and intraocular pressure (IOP) in healthy individuals was investigated. The IOP of 485 patients (970 eyes) was recorded over three nonconsecutive years (1979, 1986, 1989) which were characterized by maximal solar activity (1979, 1989) or minimal solar activity (1986). The measurements were also correlated with four categories of GMA activity: quiet (level I⁰), unsettled (II⁰), active (III⁰), and stormy (IV⁰). Participants were also differentiated by age and sex. We found that IOP was lowest on days of level IV⁰ (stormy) GMA. The drop in IOP concomitant with a decrease in GMA level was more significant during periods of low solar activity and in persons over 65 years of age. There was a trend towards higher IOP values on days of levels II⁰ and IV⁰ GMA in years of high solar activity. Differences between the sexes and among individuals younger than 65 years were not significant. Our results show an interesting aspect of environmental influence on the healthy population.     

Three dimensional visualisation of human facial exposure to solar ultraviolet.

A three dimensional computer model of the human face has been developed to represent solar ultraviolet exposures recorded by dosimeter measurements on a manikin headform under low cloud conditions and various solar zenith angles. Additionally, polysulfone dosimeters have been successfully miniaturised to provide the detailed measurements required across the face. The headform used in this research was scanned at 709 individual locations to make a wireframe mesh consisting of 18 vertical contours and 49 horizontal contours covering half the manikin's frontal facial topography. Additionally, the back of the headform and neck have also been scanned at 576 locations. Each scanned location has been used as a viable dosimeter position on the headform and represents a grid intersection point on the developed computer wireframe. A series of exposures recorded by dosimeters have been translated into three dimensional exposure ratio maps, representing ambient solar ultraviolet exposure. High dosimeter density has allowed for the development of individual topographic contour models which take into account complex variation in the face and improve upon previously employed techniques which utilise fewer dosimeters to interpolate exposure across facial contours. Exposure ratios for solar zenith angle ranges of 0 degrees -30 degrees, 30 degrees -50 degrees, and 50 degrees -80 degrees have been developed.     

A possible biophysical mechanism of the solar activity effect on the central nervous system in man

A biophysical mechanism of interaction between the man and environment is proposed, which treats these components as two correlated oscillation contours with discrete resonance frequencies. The coincidence of biocurrent frequencies of the human brain with the resonance frequencies of the cavity formed by the Earth surface and the lower ionosphere boundary allows one to consider the influence of solar flares on the human organism in terms of variations of the cavity frequencies due to changes in the parameters of its upper wall.     

Survival of microorganisms in a simulated Martian environment

Studies were conducted to determine the effects of a simulated Martian environment on the survival of terrestrial microorganisms. Mariner IV data were utilized to establish the Martian model. Day/night cycling, temperature, humidity, pressure, atmospheric constituents and solar irradiation were controlled in a 3600 ft³ simulation chamber at the Boeing Kent Space Simulation Laboratory.Microorganisms used in this study included suspensions of:Bacillus subtilis var.niger spores, a psychrophilic sporeformer, and the organisms contained in a soil emulsion prepared from several soils. Aliquots of each suspension were placed on separate sterile stainless steel planchets, air dried, and positioned in 4 layers in sterile limonite. One-half of the samples placed on the surface received the total solar spectrum (0.44 earth solar constants); the remainder of the surface samples received the above treatment minus the ultraviolet (UV) portion of the spectrum. Subsurface samples were placed in limonite at depths of 0.5, 1.5 and 3 in.Survival data were obtained for chamber exposure periods of 2, 4, and 8 days. These data indicate that: (1) organisms exposed to the total solar spectrum did not survive, (2) a time dependent, 1 to 3 log, reduction in numbers occurred in the surface samples that received the solar spectrum minus UV, and (3) subsurface survival varied with depth and type or organism.     

Modern non-drug approaches to human sleep regulation

Existing approaches to non-drug regulation and induction of human sleep are analyzed with an attempt of their classification. The main attention is paid to the methods that utilize modern computer technologies of registration and analysis of various characteristics of human organism functioning, basically to the electroencephalogram (EEG). Normal human sleep EEG correlates and their changes during different sleep stages are reviewed. Modern opportunities to regulate and induce human sleep via utilization of different EEG characteristics are analyzed.     

Cardiorespiratory characteristics and adaptation to high altitudes

The lowered partial pressure of oxygen at high altitude is one of the severest and most pervasive environmental stresses affecting human populations. Virtually all organ systems and physiological functions are affected by hypoxia, and only elaborate modern technology can temporarily ameliorate the hypoxic stress of altitude exposure. The biological and behavioral responses of newcomers, sojourners, and native residents at higher elevations could provide a paradigm of the study of man's adaptation to the physical environment. Cardiorespiratory characteristics are closely related to altitude exposure, and certain alterations in these characteristics constitute the principal adaptive responses of the organism to hypoxia. However, not all altitude-related characteristics are beneficial to the organism; some peculiar characteristics occurring at high altitude may be without benefits, or may even be pathological and maladaptive. The roles of age, sex, race, physical condition, nutrition, and intensity and frequency of exposure during growth and development of altitude-related characteristics are not entirely understood. Moreover the influence of even large circulatory and respiratory alterations, on tissue oxygen tension may be small, and their adaptive significance difficult to evaluate. An equivalent level of functional adaptation might be achieved through differing combinations of structural, functional, and behavioral characteristics. It is concluded that more rigorous evaluations of adaptation to the environment are needed.     

Functional state of various physiological systems of the human body during respiration of neon-oxygen mixture at depth up to 400 meters]

Hyperbaric neon-oxygen mixture has been studied for the effect of its high density under pressure of 41 ata on basic physiological functions of human organism. Typical changes of the cardiorespiratory system and tissue respiration parameters are revealed. Changes in physical working capacity are shown. Exposure to gaseous medium of high pressure and density is accompanied by the development of some compensatory-adaptive reactions. The possibility to perform mid-hard physical work is attained with overstrain of respiration and circulation function.     

Hemagglutinating activity of Mycoplasma salivarium and its attachment to sheep red blood cells

Mycoplasma salivarium (ATCC 23064) and 10 other strains isolated from human saliva agglutinated red blood cells of rabbits and human types A and O weakly, and those of sheep (SRBC) and human type B strongly. Glycoproteins on the surface of the organism cells and N-acetylneuraminic acid residues and some sugars on SRBC were suggested to be involved in agglutination of SRBC. Protein A-like activity was detected in the organism cells. The organism cells were also shown to attach to SRBC in PPLO broth (Difco) supplemented with 10% horse serum, and bivalent metal ions were suggested to be involved in the attachment. The organism cells attaching to SRBC activated complement through the alternative pathway and lyzed the SRBC.     

The human adaptations to meat eating: a reappraisal

In this paper we discuss the hypothesis, proposed by some authors, that man is a habitual meat-eater. Gut measurements of primate species do not support the contention that human digestive tract is specialized for meat-eating, especially when taking into account allometric factors and their variations between folivores, frugivores and meat-eaters. The dietary status of the human species is that of an unspecialised frugivore, having a flexible diet that includes seeds and meat (omnivorous diet). Throughout the various time periods, our human ancestors could have mostly consumed either vegetable, or large amounts of animal matter (with fat and/or carbohydrates as a supplement), depending on the availability and nutrient content of food resources. Some formerly adaptive traits (e.g. the “thrifty genotype”) could have resulted from selective pressure during transitory variations of feeding behaviour linked to environmental constraints existing in the past.     

Errors associated with using Archimedes' principle to determine mass and volume of small aquatic organisms

Archimedes' principle can be effectively applied to measure the mass and volume of small aquatic organisms by weighing the organism in waters of two densities, and then comparing those values with the weights of a plummet weighed in the same waters. However, the weight-in-water measurements are subject to error, and this work outlines how to calculate the standard errors of organism mass and volume, and a straightforward approach to calculating organism mass and volume itself. Guidance for the design of a plummet and setting a water density difference that minimizes the standard errors of the measurements is also presented.     

Predicted inactivation of viruses of relevance to biodefense by solar radiation

UV radiation from the sun is the primary germicide in the environment. The goal of this study was to estimate inactivation of viruses by solar exposure. We reviewed published reports on 254-nm UV inactivation and tabulated the sensitivities of a wide variety of viruses, including those with double-stranded DNA, single-stranded DNA, double-stranded RNA, or single-stranded RNA genomes. We calculated D(37) values (fluence producing on average one lethal hit per virion and reducing viable virus to 37%) from all available data. We defined "size-normalized sensitivity" (SnS) by multiplying UV(254) sensitivities (D(37) values) by the genome size, and SnS values were relatively constant for viruses with similar genetic composition. In addition, SnS values were similar for complete virions and their defective particles, even when the corresponding D(37) values were significantly different. We used SnS to estimate the UV(254) sensitivities of viruses for which the genome composition and size were known but no UV inactivation data were available, including smallpox virus, Ebola, Marburg, Crimean-Congo, Junin, and other hemorrhagic viruses, and Venezuelan equine encephalitis and other encephalitis viruses. We compiled available data on virus inactivation as a function of wavelength and calculated a composite action spectrum that allowed extrapolation from the 254-nm data to solar UV. We combined our estimates of virus sensitivity with solar measurements at different geographical locations to predict virus inactivation. Our predictions agreed with the available experimental data. This work should be a useful step to understanding and eventually predicting the survival of viruses after their release in the environment.     

Migration of smolts of Atlantic salmon (Salmo salar L.) and sea trout (Salmo trutta L.) in a chalkstream

Synopsis Migration of smolts in the River Piddle, Dorset, was studied over three years in relation to factors that could influence downstream movement. The river originates mostly from groundwater springs, resulting in stable flows and low turbidity except in very rainy weither. Fish were intercepted at the tidal limit in a fixed trap-net, and measurements of water temperature, discharge, turbidity, barometric pressure, rainfall and solar radiation taken nearby. Slightly increased turbidity and discharge following heavy rain initiated major movements during two nights of the total of 55 days studied. At other times large-scale movements rock place during sunny warm afternoons. Both solar radiation and water temperature were correlated with intensity and timing of movement. The pattern of migration is different from that reported on other rivers, reflecting the relatively stable flow regime of the chalkstream.     

The Intelligent Egg, and How It Got That Way: from Genes to Genius in a Few Easy Lessons

A seed has no flowers or leaves, and an egg no fingers or lungs. Yet plants and animals not only have these things but they resemble their parents in detail throughout their bodies. Something is inherited, but what is it? Life is based on the activities of cells. An organism has large numbers of them—a human has trillions! Cells live as separate units, which enables them each to do its own thing within its particular organ, but to be an organism they must work together. A cell can only detect its immediate local environment, but that includes various kinds of signals or information from nearby or far away within the body—or even from the external environment. It is by being local but responding globally in this way that an egg becomes an organism, an organism manages its way through life, and organisms make up species and ecosystems that interact with each other. The evolution of these abilities has produced the glorious array of living forms that populate the world. In these ways, an egg may have no thoughts but is a highly intelligent being.     

Ultraviolet irradiation and repair--possible factors determining the evolution of DNA structure

It is suggested that DNA in first organisms on the Earth was enriched by GC-pairs due to intensive solar UV-irradiation. In the course of progressive evolution, nucleotide composition of DNA shifted to the favour of AT-pairs. This shift to higher photosensitivity became possible because of the development of reparation systems and screening of DNA in cells. The latter phenomenon is better revealed in higher organisms, accounting their stable TA-type of DNA. In lower forms, peculiarities of their habitats provided some conditions for variability of nucleotide composition. High content of GC-pairs remained in those of them which are subjected to the influence of solar irradiation. Parasitic microorganisms and those safely protected from solar radiation developed towards the AT-type of DNA. Both in higher and lower organisms, AT-pairs are richer in those zoms of DNA which are presented by several copies and in which mutations are less significant for the organism therefore being permissible. Structural genes exhibit heterogeneous nucleotide composition which provides for higher variability of the synthesized proteins.     

Evolutionary divergence of the nuclear pore complex from fungi to metazoans

Nuclear pore complex (NPC) is the largest multimeric protein assembly of the eukaryotic cell, which mediates the nucleocytoplasmic transport. The constituent proteins of this assembly (nucleoporins) are present in varying copy numbers to give a size from ~ 60 MDa (yeast) to 112 MDa (human) and share common ancestry with other membrane‐associated complexes such as COPI/COPII and thus share the same structural folds. However, the nucleoporins across species exhibit very low percentage sequence similarity and this reflects in their distinct secondary structure and domain organization. We employed thorough sequence and phylogenetic analysis guided from structure‐based alignments of all the nucleoporins from fungi to metazoans to understand the evolution of NPC. Through evolutionary pressure analysis on various nucleoporins, we deduced that these proteins are under differential selection pressure and hence the homologous interacting partners do not complement each other in the in vitro pull‐down assay. The super tree analysis of all nucleoporins taken together illustrates divergent evolution of nucleoporins and notably, the degree of divergence is more apparent in higher order organisms as compared to lower species. Overall, our results support the hypothesis that the protein–protein interactions in such large multimeric assemblies are species specific in nature and hence their structure and function should also be studied in an organism‐specific manner.     

Rationalizing the Molecular Design of Hole‐Selective Contacts to Improve Charge Extraction in Perovskite Solar Cells

Two new hole selective materials (HSMs) based on dangling methylsulfanyl groups connected to the C‐9 position of the fluorene core are synthesized and applied in perovskite solar cells. Being structurally similar to a half of Spiro‐OMeTAD molecule, these HSMs (referred as FS and DFS) share similar redox potentials but are endowed with slightly higher hole mobility, due to the planarity and large extension of their structure. Competitive power conversion efficiency (up to 18.6%) is achieved by using the new HSMs in suitable perovskite solar cells. Time‐resolved photoluminescence decay measurements and electrochemical impedance spectroscopy show more efficient charge extraction at the HSM/perovskite interface with respect to Spiro‐OMeTAD, which is reflected in higher photocurrents exhibited by DFS/FS‐integrated perovskite solar cells. Density functional theory simulations reveal that the interactions of methylammonium with methylsulfanyl groups in DFS/FS strengthen their electrostatic attraction with the perovskite surface, providing an additional path for hole extraction compared to the sole presence of methoxy groups in Spiro‐OMeTAD. Importantly, the low‐cost synthesis of FS makes it significantly attractive for the future commercialization of perovskite solar cells.     

Transpiration flow rate in a full-grown tree ofPrunus avium L. estimated by the method of heat balance in connection with some meteorological factors

The course of the transpiration flow rate (Q_w), of transpiration flow acceleration (Q_w/dt) and of the integrated transpiration flow was determined during an average summer day by repeated measurements according to the method of heat balance and the free water capacity of the tree trunk was estimated. The relations between the transpiration flow rate and the temperature and relative humidity of the air and the vapour pressure deficit measured at the same time in their diurnal course, as well as at the single diurnal terms during the whole time at which measurements were carried out were determined by correlation analysis. The problems linked with the effect of various meteorological conditions during different times of the day, of rain showers, solar radiation and soil water content are discussed. The possibilities of explaining the midday depression of transpiration on the basis of repeated measurements of the transpiration flow rate are evaluated.     

On the role of flavonoids in the integrated mechanisms of response of Ligustrum vulgare and Phillyrea latifolia to high solar radiation

The role of flavonoids in mechanisms of acclimation to high solar radiation was analysed in Ligustrum vulgare and Phillyrea latifolia, two Mediterranean shrubs that have the same flavonoid composition but differ strikingly in their leaf morpho-anatomical traits. In plants exposed to 12 or 100% solar radiation, measurements were made for surface morphology and leaf anatomy; optical properties, photosynthetic pigments, and photosystem II efficiency; antioxidant enzymes, lipid peroxidation and phenylalanine ammonia lyase; synthesis of hydroxycinnamates and flavonoids; and the tissue-specific distribution of flavonoid aglycones and ortho-dihydroxylated B-ring flavonoid glycosides. A denser indumentum of glandular trichomes, coupled with both a thicker cuticle and a larger amount of cuticular flavonoids, allowed P. latifolia to prevent highly damaging solar wavelengths from reaching sensitive targets to a greater degree than L. vulgare. Antioxidant enzymes in P. latifolia were also more effective in countering light-induced oxidative load than those in L. vulgare. Consistently, light-induced accumulation of flavonoids in L. vulgare, particularly ortho-dihydroxylated flavonoids in the leaf mesophyll, greatly exceeded that in P. latifolia. We conclude that the accumulation of flavonoid glycosides associated with high solar radiation-induced oxidative stress and, hence, biosynthesis of flavonoids appear to be unrelated to 'tolerance' to high solar radiation in the species examined.     

Ambulatory blood pressure monitoring: assessing the diurnal variation of blood pressure

The purposes of this paper are to examine the effects of activity, situation of measurement, mood, and occupation on the daily variation of blood pressure and to discuss the potential utility of ambulatory blood pressure monitoring in physical anthropological studies. The subjects of the blood pressure variability study are 125 men who were referred to the Hypertension Center at New York Hospital--Cornell Medical Center for evaluation of hypertension. There were 1,386 blood pressure measurements from these subjects available for study, which were taken using noninvasive ambulatory blood pressure monitoring techniques. Pressures were transformed to z scores using the subject's daily mean pressure and standard deviation to assess the relative elevation during the experience of the various factors. The results show that activity and mood are the most significant sources of blood pressure variation (P less than .005) and are additive. Occupation, which may be an indicator of social class in this population, also modified the mood effects. Because ambulatory blood pressure monitors obtain many readings over a day under a variety of circumstances, their use can improve epidemiological and human biological studies of the inheritance and variability of blood pressure. Ambulatory blood pressure monitoring is an important new tool in the study of human biological variation.