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At least 19 recordsLinked to original sources
PubMed1993

Photoperiod, temperature, and regional patterns of conceptions in the USA.

Twenty-two years of monthly values of birth data for the USA, 1967 through 1988, were analyzed by visual inspection. The data were transformed to remove the influence of length of month and of linear trend, and the values were lagged 9 months to approximate the time of conception. Then, 11-year monthly averages were obtained and plotted as standard scores. Thus two 11-year sets of data were independently analyzed, providing the opportunity of replication. Four distinct temporal patterns were found, differing in month of occurrence of the initial trough and peak and the relative sizes of the two troughs; these characteristics of the temporal pattern change systematically with latitude in the eastern and midwestern states. Data from two other continents, the United Kingdom and Australia, also were analyzed using the same method and found to exhibit a temporal pattern during the year similar to the northern states of the USA. Two biologically relevant variables, temperature and photoperiod, were considered as possible controllers and regulators of the annual rhythmicity. Comparisons of the trends in conceptions with these environmental variables, and inspections of the temperatures and photoperiods at which peaks and troughs in conceptions were found, indicated that these environmental variables could not account for the annual rhythmicity in conceptions.

Birth Rate↗
PubMed1991

An eleven-year cycle in human births.

The prominent endogenous cycle of the sun, with a period of approximately 11 years, is correlated with human conceptions. Time series methods (periodograms and periodic regression analyses) established that an approximate 11-year period exists in the data on births in the 20th century (1909-1985) in the United States and in New Zealand. Statistical comparisons indicated a reliable and direct relationship of conceptions with the approximately 11-year sunspot cycle. These findings were discussed in terms of the possible mediating role of geomagnetic disturbances and other factors that have been suggested in the literature to mediate human conception.

Birth Rate↗
PubMed1990

[Health-related and pathogenetic aspects of vascular diseases of the nervous system].

A concept of the dynamic patho- and sanogenesis of vascular diseases of the nervous system was developed on the basis of clinico-physiological studies. The concept is based on the data on the philo- and ontogenesis, reactivity and adaptability+, complexity and dynamism, stages and phases of the process. The concept suggested may serve the basis for elaborating the program of preventing cerebrovascular diseases.

Adaptation, Physiological↗
PubMed1990

The solar wind and human birth rate: a possible relationship due to magnetic disturbances.

Data obtained from the literature on the annual pattern of human conceptions and plasma melatonin at high latitudes indicated that simple annual rhythms do not exist. Instead, prominent semiannual rhythms are found, with equinoctial troughs and solsticial peaks. A prominent semiannual environmental event is the magnetic disturbance induced by the solar wind. The semiannual magnetic disturbances are worldwide, but most pronounced in the auroral zones where the corpuscular radiation enters the atmosphere. Magnetic indices that predominantly reflect these events were obtained from the literature and correlated with the melatonin and conception data. Significant and inverse correlations were found for Inuit conceptions and the melatonin data. The correlations obtained for 48 contiguous states of the United States indicated that only the extreme northern states exhibited this relationship. These data were compared with a previous correlational study in the United States which established that sunshine was correlated with conceptions in the middle latitude and southern states. An hypothesis of dual control by electromagnetic and magnetic energies is proposed: melatonin is a progonadal hormone in humans controlled by both factors, depending on their relative strength. Other studies are reviewed regarding the possible factors involved in determining the annual pattern of human conceptions. Demographic studies of geographic variation in temporal patterns of conceptions, with particular regard to variations of the magnetic fields on the earth's surface, may provide some insight into the efficacy of these different factors.

Birth Rate↗
PubMed1995

The human bioclimates of Western and South Pacific islands and climate change.

The current bioclimates of equatorial Western and tropical South Pacific have been assessed, using the concepts of effective temperature and relative strain as a basis for evaluating likely changes in human comfort regimes as a consequence of global warming. Current bioclimates may be considered marginally stressful for indigenous populations. Global warming will result in changes in the frequency, duration and intensity of physioclimatically stressful conditions.

Greenhouse Effect↗
PubMedDate not supplied

A sophisticated lander for scientific exploration of Mars: scientific objectives and implementation of the Mars-96 Small Station.

A mission to Mars including two Small Stations, two Penetrators and an Orbiter was launched at Baikonur, Kazakhstan, on 16 November 1996. This was called the Mars-96 mission. The Small Stations were expected to land in September 1997 (Ls approximately 178 degrees), nominally to Amazonis-Arcadia region on locations (33 N, 169.4 W) and (37.6 N, 161.9 W). The fourth stage of the Mars-96 launcher malfunctioned and hence the mission was lost. However, the state of the art concept of the Small Station can be applied to future Martian lander missions. Also, from the manufacturing and performance point of view, the Mars-96 Small Station could be built as such at low cost, and be fairly easily accommodated on almost any forthcoming Martian mission. This is primarily due to the very simple interface between the Small Station and the spacecraft. The Small Station is a sophisticated piece of equipment. With the total available power of approximately 400 mW the Station successfully supports an ambitious scientific program. The Station accommodates a panoramic camera, an alpha-proton-x-ray spectrometer, a seismometer, a magnetometer, an oxidant instrument, equipment for meteorological observations, and sensors for atmospheric measurement during the descent phase, including images taken by a descent phase camera. The total mass of the Small Station with payload on the Martian surface, including the airbags, is only 32 kg. Lander observations on the surface of Mars combined with data from Orbiter instruments will shed light on the contemporary Mars and its evolution. As in the Mars-96 mission, specific science goals could be exploration of the interior and surface of Mars, investigation of the structure and dynamics of the atmosphere, the role of water and other materials containing volatiles and in situ studies of the atmospheric boundary layer processes. To achieve the scientific goals of the mission the lander should carry a versatile set of instruments. The Small Station accommodates devices for atmospheric measurements, geophysical and geochemical studies of the Martian surface and interior, and cameras for descent phase and panoramic views. These instruments would be able to contribute remarkably to the process of solving some of the scientific puzzles of Mars.

Atmosphere↗
PubMed1994

Correlation between meteorological conditions and mutagenicity of airborne particulate samples in a tropical monsoon climate area from Kaohsiung City, Taiwan.

Kaohsiung is a city of 1.5 million located in the southern part of Taiwan. It has a serious air pollution problem mainly attributable to much industrial and commercial activity. In order to estimate the effects of traffic, season, and meteorological conditions on the mutagenicity of Kaohsiung City's urban ambient particulate matter, 624 airborne particulate samples were collected on a weekly basis from 12 locations for an entire year. The mutagenic potential of acetone extracts of air samples was evaluated by the Salmonella/microsomal test with S. typhimurium TA98 in the presence and absence of S9 mixtures. The air samples from November 1990 showed the highest direct and indirect mutagenicity among the 12 months, whereas those from June and July 1991 had the lowest direct and indirect mutagenic activity, respectively. The mutagenicity showed a good correlation with amounts of the acetone extractable matter of airborne particulates. The meteorological conditions, monthly mean precipitation, and wind speed also showed a good correspondence with mutagenicity. Wind direction and temperature had a moderate relationship. The major mutagenic fractions of air samples that had the highest mutagenic activity in a month were purified using Sephadex LH-20 column chromatography, and the contents of PAHs, 1-NP, and DNPs were analyzed by HPLC. The characteristic concentration ratios of PAHs indicated that, for the main pollution sources of airborne particulates from Kaohsiung city, the mobile sources were more important than the stationary ones. The total amounts of 1-NP and DNPs in airborne particulates seemed to correspond to their mutagenicity. Although the total amounts of 1-NP and DNPs in the air samples correlated with their mutagenicity, the major mutagenic chemicals in the airborne particulate samples from Kaohsiung City need further investigation.

Air Pollutants↗
PubMed1994

Reproductive interactions between two Australian reptile tick species.

In South Australia the two tick species Amblyomma limbatum and Aponomma hydrosauri share the same common reptile host species, but have allopatric distributions which abut along a narrow parapatric boundary. Reproductive interference is a mechanism that has previously been suggested could contribute to maintaining the boundary. Populations of each species were established in pens within the range of Aponomma hydrosauri. Pens held either each species alone, or the two species together. The performance of females in those pens was monitored over 28 months. There was no indication that the proportion of attached females which mated and engorged was reduced by the presence of heterospecifics. There was no indication that the time taken to mate, engorge and detach was any longer in the presence of heterospecifics. The experiment did not support the hypothesis that reproductive interference contributes to maintaining the parapatric boundary. However, Amblyomma limbatum in the pens had a shorter season of reproductive activity, and achieved much smaller numbers of reproductive females. This may inhibit successful colonization of cooler habitats to the south of its distribution.

Animals↗
PubMed1994

Comparative reproduction and nonparasitic development of Boophilus microplus and hybridized Boophilus ticks (Acari: Ixodidae) under natural field conditions in subtropical south Texas.

The reproductive biology and nonparasitic development of Boophilus microplus (Canestrini) and hybridized Boophilus ticks (B. annulatus (Say) male x B. microplus female) held under natural field conditions in south Texas throughout the year were compared. Comparisons between the two types of ticks indicated that the ovipositional biology (percentage of ovipositing females and number of eggs laid) of the females favored hybrid ticks during some months and B. microplus ticks during other months. However, on a year long basis, there was virtually no difference in the percentage of ovipositing females or in the number of eggs deposited by hybrid females as compared to B. microplus. The duration of each nonparasitic development period (preoviposition period, incubation period of eggs, and larval longevity) showed that both types of ticks had very similar developmental and survival rates during the year. Generally the difference in duration of each of the nonparasitic parameters was < 8 days, leading to a high degree of synchrony of the nonparasitic developmental rates between the two types of ticks. On the other hand, egg hatchability of hybrid ticks was consistently lower than pure-strain B. microplus throughout the year with significantly lower hatch rates occurring in April, July, August, October, and November. Thus, results obtained on percentage of ovipositing females, number of eggs laid, preoviposition period, incubation period of eggs, and larval longevity provide encouragement for the possible use of sterile hybrid males as a means of eliminating a native B. microplus population. In contrast, results of the egg hatchability of the two types of ticks indicate that the selective advantage afforded to B. microplus could have an adverse affect on the success of a sterile hybrid male program by making the number of hybrid ticks necessary to eliminate a native population prohibitively high.

Animals↗
PubMed1993

Effect of climatic elements on the frequency of secretory otitis media.

A relationship between the number of children hospitalized for secretory otitis media and climatic elements was observed during a 10-year period (1981-1990). The highest correlation was obtained between the number of secretory otitis media cases and the number of sunny hours in a month, followed by that between the number of secretory otitis media cases and the mean monthly temperature and relative air humidity. The largest number of children were hospitalized for secretory otitis media toward the end of winter, and the lowest toward the end of summer (in August and September).

Child↗
PubMed1991

Hospital cardiovascular deaths and total distribution of deaths in 180 consecutive months with different cosmic physical activity: a correlative study (1974-1988).

The dynamics of total hospital deaths from different kinds of cardiovascular diseases in one 1000-bed hospital were compared with 10 monthly cosmic/solar and geomagnetic physical activity parameters. Data used were of 180 consecutive months; 15,601 deaths including 5667 from cardiovascular diseases were included in this study. It was concluded that the number of monthly hospital deaths shows a highly significant correlation with monthly solar physical activity.

Cardiovascular Diseases↗
PubMed1989

An introduction to the theory of NON-uniformity of hygrothermal constituent of the environment.

Non-uniformity of the hygrothermal constituent of the environment (NUN) causes problems not only of hot workplaces in industry, but also in lightweight buildings, and air-conditioned and even ventilated buildings. It is almost impossible to avoid cold draughts, unilateral thermal radiation etc. in such situations. The theory and definition of NUN in space and in time, and NUN climatic (convective, radiant, perspiratory) and NUN conductive are described.

Body Temperature Regulation↗
PubMed1989

Record performances at the Boston Marathon: biometeorological factors.

Air temperature and relative humidity have long been suspected of affecting the performance of marathon runners. Though these factors are important in their extremes, we show that other factors are even more indicative of race performances. Performances of the top 3 finishers in the last 30 Boston Marathons were correlated with hourly meteorological data for each race day. These 90 individual performances were classified as: record breaking performances (31), average performances (35), and unusually slow performances (24). The factors that help predict record breaking and unusually slow performances are: (i) wet bulb temperature, (ii) percent sky cover, and (iii) presence or absence of a light precipitation. Record breaking performances are characterized by a wet bulb temperature of less than 7.8 degrees C, and 100% sky cover. A light drizzle is also conducive to better performances. On the other hand, unusually low performances are accompanied by a wet bulb temperature of greater than 7.8 degrees C, and a sky cover of 50% or less. No light precipitation was recorded on any of the unusually slow race days. A graphic analysis clearly shows these relationships to exist. In addition, a multiple regression analysis confirms the importance of these variables. The authors advise that these are reliable predictors; however, when considering marathon races held in various geographical regions and differing climatic regimes, the exact numerical thresholds used here may not apply.

Boston↗
PubMed1990

Forecasting spore concentrations: a time series approach.

Fungal basidiospores and Cladosporium spores are the two most numerous spore types in the air of Dublin and its surroundings. They are known to have allergenic components, and the aim of the study described here is to develop a predictive model for these spores. A very simple model, which combines an estimated diurnal rhythm with a simple, one-parameter time series model, provided good short-term forecasts. The one-step prediction error variance was reduced by 88% for Cladosporium spores and by 98% for basidiospores.

Air Microbiology↗
PubMed1990

Too hot for comfort: the heatwaves in Greece in 1987 and 1988.

The heatwaves that affected Greece in July 1987 and July 1988 are considered in terms of (i) the relative strain index. For different types of activity, and (ii) the discomfort index. Hourly values of air temperature and humidity for Thessaloniki and Athens were used as the data base. Both indices show that in terms of physiological strain and general discomfort, Thessaloniki suffered a little more and a little longer than Athens. We conclude that the relative strain index is probably a useful tool in studies of the adverse effects of humid heatwaves on different sections of a population.

Greece↗