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1.
Hans de Beer 《Economics & Human Biology》2004,2(1):45-55
In the late-Middle Ages and at the onset of the early modern period, the Dutch population was taller than in the first half of the 19th century. This inference is partially based on skeletal evidence, mainly collected by the Dutch physical anthropologist George Maat and his co-workers. A spectacular increase in Dutch heights began in the second half of the 19th century and accelerated in the second half of the 20th century. At the end of the 20th century, the Dutch became tallest in the world. 相似文献
2.
Zariņa G 《Anthropologischer Anzeiger; Bericht über die biologisch-anthropologische Literatur》2006,64(2):189-202
The study represents palaeodemographic research of osteological material of 3304 individuals from the funds of the Anthropological Laboratory of the Institute of History of the University of Latvia in Riga, dating from the 7th to the 18th century AD. Compensated life expectancy at birth is varying between 20.3 and 22.2 years during the research period. Crude mortality has changed between 49.3 and 45% per hundred. In the early period (7th-13th century) there is a significant male prevalence (2.2-1.4); female life expectancy at the age of 20 is on average 6.6 years less than for males. This difference decreases to 5.4 years in the 13th-18th century. According to historical demography, female life span exceeded male only in the 2nd half of 19th century. The palaeodemographic data indicate that in the 7th-18th century, women in Latvia gave birth to a mean of 4-5 children (the figure includes childless women), of whom half, at most 2-2.5, reached reproductive age, on account of high child mortality. The net reproductive rate R0 (the number of descendants per individual of the parents' generation) varies between 1 and 1.25 in the study period. Concerning the completely excavated cemeteries of Lejasbiteni (7th-10h century) and Daudziesi (16th-17th century), it was possible to calculate the size and structure of the populations that had used these cemeteries. They were similar, having 45.3-49.9% of children up to an age of 14 and 24-28% individuals over the age of 30. According to historical demography, radical improvement of the demographic situation in Latvia began in the second half of the 19th century, when the process of demographic transition in Latvia started. 相似文献
3.
Barbara P Yawn George E Fryer Robert L Phillips Susan M Dovey David Lanier Larry A Green 《BMC pulmonary medicine》2005,5(1):1-7
Background
The recent increase in childhood asthma has been a puzzling one. Recent views focus on the role of infection in the education of the immune system of young children. However, this so called hygiene hypothesis fails to answer some important questions about the current trends in asthma or to account for environmental influences that bear little relation to infection.Discussion
The multi-factorial nature of asthma, reflecting the different ways we tend to interact with our environment, mandates that we look at the asthma epidemic from a broader perspective. Seemingly modern affluent lifestyles are placing us increasingly in static, artificial, microenvironments very different from the conditions prevailed for most part of our evolution and shaped our organisms. Changes that occurred during the second half of the 20th century in industrialized nations with the spread of central heating/conditioning, building insulation, hygiene, TV/PC/games, manufactured food, indoor entertainment, cars, medical care, and sedentary lifestyles all seem to be depriving our children from the essential inputs needed to develop normal airway function (resistance). Asthma according to this view is a manifestation of our respiratory maladaptation to modern lifestyles, or in other words to our increasingly artificial habitats. The basis of the artificial habitat notion may lie in reduced exposure of innate immunity to a variety of environmental stimuli, infectious and non-infectious, leading to reduced formulation of regulatory cells/cytokines as well as inscribed regulatory pathways. This could contribute to a faulty checking mechanism of non-functional Th2 (and likely Th1) responses, resulting in asthma and other immuno-dysregulation disorders.Summary
In this piece I discuss the artificial habitat concept, its correspondence with epidemiological data of asthma and allergy, and provide possible immunological underpinning for it from an evolutionary perspective of health and disease. 相似文献4.
The link between phosphoinositide turnover and Ca2+-regulated cell processes goes back half a century, but only began to be understood in the 1970s. This article briefly outlines how the roles of these minority membrane lipids in Ca2+ signalling and then in multifarious other biological processes were recognised during the latter half of the 20th century. 相似文献
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6.
L. V. Kapitonova S. M. Smirenskii D. S. Selivanova V. V. Fedorov N. A. Formozov 《Biology Bulletin》2011,38(9):912-926
The history of ranges of the great tit (Parus major) and Japanese tit (P. minor) in the Amur River basin is described on the basis of original data collected between 1970 and 2010 and published data. The
main factor accounting for the expansion of the great and Japanese tits to the Amur basin and neighboring territories in the
19th to 21st centuries is economic activity, primarily agriculture and timber harvesting. The approximate range boundaries
and the sympatry zone of these two species have been determined for the second half of the 19th century; the beginning, middle,
and third quarter of the 20th century; and the turn of the 21st century. Three different ecological channels consecutively
played the main role in the eastward expansion of the great tit: the Amur River valley (from the mid-19th to the early 20th
century), the Trans-Siberian Railroad (since the early 20th century), and the Baikal-Amur Railroad (since the 1970s). It is
shown that the concept concerning the finding of great tits in Udskii Ostrog by Middendorff’s expedition is erroneous: according
to dates on the labels, the corresponding two specimens were in fact collected in a different geographic locality. It has
been found that Komsomolsk-on-Amur is a new locality jointly inhabited by both species, independent of the main zone of their
sympatry. It has appeared very recently, at the turn of the 21st century. 相似文献
7.
Alexander Y. Karatayev Sergey E. Mastitsky Lyubov E. Burlakova Sergej Olenin 《Biological invasions》2008,10(2):215-232
We analyzed the role of the waterways of Belarus in the spread of aquatic exotic invertebrates through the central European
invasion corridor. Present day Belarus became critically important when in the end of the 18th—beginning of the 19th century
three interbasin canals connecting rivers from the Black and Baltic seas basins were constructed for international trade.
These canals became important pathways facilitating the spread of aquatic alien species. For more than a hundred years, only
Ponto-Caspian species colonized Belarus using ships and especially timber in rafts exported by Russia into Western Europe.
In the second half of the 20th century, new vectors of spread appeared in Belarus, such as stocking of economically important
invertebrates and accidental introductions. This paper is the first comprehensive review of aquatic exotic invertebrates in
Belarus. Currently, 19 exotic aquatic invertebrates are known in Belarus, including 14 species of Ponto-Caspian origin. The
rate of spread of aquatic invasive species in the second half of the 20th century increased 7-fold compared to the 19th—beginning
of the 20th century. We found a significant positive correlation between the time since initial invasion and number of waterbodies
colonized. We predict a further increase in the rate of colonization of Belarus by exotic invertebrates as well as an increase
in the diversity of vectors of spread and donor areas of alien species, especially when the ongoing reconstruction of the
interbasin canals will be completed and the hydrological connection between Black Sea and Baltic Sea basins will be reestablished
after an interruption that has lasted for almost a century. 相似文献
8.
Nutrient-poor freshwater wetlands 总被引:1,自引:1,他引:0
L. W. G. Higler 《Hydrobiologia》1993,265(1-3):195-201
Until the introduction of fertilizers in the 19th century nutrient-poor conditions prevailed in the larger part of The Netherlands.
Freshwater wetlands consequently were of nutrient-poor nature. During the first half of the 20th century many surface waters
gradually eutrophied, but most waters in the Pleistocene area and even some polders in the Holocene area kept their nutrient-poor
conditions. Only during the last decades virtually all waters became eutrophied or polluted. The main sources of nutrients
are agriculture, precipitation and water from the large rivers. 相似文献
9.
Prof. Ernst Mayr 《BioEssays : news and reviews in molecular, cellular and developmental biology》1997,19(2):175-179
Dr Ernst Mayr has been one of the seminal figures of 20th century biology. His essential contributions were in the development of the Modern Synthesis in evolutionary biology. His landmark book Systematics and the Origin of Species, was published in 1942 and has long been acknowledged as one of the key foundations of 20th century evolutionary biology. In many subsequent articles and books on evolution and the history and philosophy of biology during the past half century, he has continued to be a key contributor of ideas and inspiration to successive generations of evolutionary biologists. In the first of two ‘Roots’ articles, he describes the early stages of his career and the serendipitous events that furthered it. This article was first presented as a talk, on October 27, 1993, at the 50 year Jubilee celebration of the founding of the Whitney wing, the ornithological section, of the American Museum of Natural History in New York City. In next month's ‘Roots’ article, Dr Mayr will describe the events that led to the founding of the Society for the Study of Evolution in 1946, in St Louis, Missouri. 相似文献
10.
As a result of mining activities, two related graveyards dating from the last decade of the 19th century and first half of the 20th century had to be relocated. This provided the opportunity to study 47 skeletons of black South Africans, with the aim of obtaining information on the health status and life style of people from a rural area in a mostly pre-antibiotic era. Although the sample is too small to do a proper palaeodemographic analysis, the age spread of the individuals indicates a high infant mortality rate and generally low life expectancy. Medical services were available, as could be seen from the surgically treated forearm fracture of one individual. One individual had signs of a possible treponemal infection, while subperiosteal bone growth on the ribs of another may indicate tuberculosis. High incidences of arthritic disease and joint degeneration probably indicate a high work load. Enlarged fontanelles with delayed closure were noted in some of the infants. Data on long bone lengths also indicate that the growth of the children may have been retarded in comparison to other similarly aged children. It thus seems as though this was a community under considerable stress. A surprising find was the unusually high incidence of individuals with dental abnormalities and variations. 相似文献
11.
In the 20th century geneticists began to unravel some of the simpler aspects of the etiology of inherited diseases in humans. The theory of linkage analysis was developed and applied long before the advent of molecular biology, but only the technological advances of the second half of the 20th century made large-scale gene mapping with a dense genome-spanning set of markers a reality. More recently, the primary topic of interest has shifted from simple Mendelian diseases, for which genotypes of some gene are the cause of disease, to more complex diseases, for which genotypes of some set of genes together with environmental factors merely alter the probability that an individual gets the disease, although individual factors are typically insufficient to cause the disease outright. To this end, a great deal of dogma has evolved about the best way to skin this cat, although to date success has been minimal with any approach. We postulate that the main reason for this is a lack of attention to experimental design. Once the data have been ascertained, the most powerful statistical methods will not be able to salvage an inappropriately designed study (Andersen 1990). Each phenotype and/or population mandates its own individually tailored study design to maximize the chances of successful gene mapping. We suggest that careful consideration of the available data from real genotype-phenotype correlation studies (as opposed to oversimplified theoretically tractable models), and the practical feasibility of different ascertainment schemes dictate how one should proceed. In this review we review the theory and practice of gene mapping at the close of the 20th century, showing that most methods of linkage and linkage disequilibrium analysis are similar in a fundamental sense, with the differences being related more to study design and ascertainment than to technical details of the underlying statistical analysis. To this end, we propose a new focus in the field of statistical genetics that more explicitly highlights the primacy of study design as the means to increase power for gene mapping. 相似文献
12.
Vasil'eva LI 《Genetika》2002,38(4):546-553
Marriage records from parish books of the second half of the 19th century and marriage records of 1967-1970 and 1993-1995 obtained from registry offices were used to analyze the dynamics of genetically significant parameters of migration and marriage structure with respect to spouses' birthplaces in populations of different hierarchical levels in the Kursk oblast. It was found that, among the persons contracting marriage (both males and females), the proportions of those who were born in the same population and those who were born in any population of the Kursk oblast decreased by about one third and one fifth, respectively, for the 130-year period. In rural and small urban populations, the coefficients of marriage migration in the 19th century were an order of magnitude lower than in the 20th century. The immigration to urban populations was maximum in the late 1960s (m = 0.745 in small towns and m = 0.680 in Kursk), and that to rural populations, in the 1990s (m = 0.344). In both urban and rural populations, the mean distance between the spouses' birthplaces has increased by several times for the period studied. The endogamy level has decreased approximately twofold: from 0.797 to 0.380 in Kursk, from 0.897 to 0.419 in small towns, and from 0.958 to 0.440 in rural districts. The marriage assortativeness with respect to birthplace was maximum in the late 19th century (K = 0.393-0.491) and minimum in the 1960s (K = 0.155-0.246). The increase in genetic diversity of the urban population of the Kursk oblast due to migration has been slowing down since the late 20th century, whereas the outbreeding level is still increasing in rural populations. 相似文献
13.
Australasian contributions to an understanding of the epidemiology and control of hydatid disease caused by Echinococcus granulosus--past, present and future 总被引:13,自引:0,他引:13
M A Gemmell 《International journal for parasitology》1990,20(4):431-456
For several years after Echinococcus granulosus was introduced into Australasia from Europe, its life cycle was unknown. Before the end of the 19th century, however, Cystic Hydatid Disease (CHD) was recognized in humans as an important cause of death, although its magnitude was not quantified. During the first 50 years of the 20th century, the urban component declined, but CHD remained a serious source of ill-health. During the second half of the 20th century major research contributions have included: (i) differentiation of pastoral from wildlife Echinococcus and (ii) breaking the 'epidemiological code' of the family Taeniidae, thereby defining the conditions under which transmission occurs. Based on this research and concurrent surveys, it is concluded that the present geographical distribution of E. granulosus in domestic animals and CHD in the rural population is determined by climate; being uncommon where hot dry seasons continue beyond a few months. The parasite's range may be extended in its wildlife cycle through a highly susceptible definitive host--the dingo. The ease with which blowflies transfer taeniid eggs from dog faeces to animal and human foodstuffs implies that in Australasia, CHD can sometimes be regarded as foodborne. A perceived decline in autochthonus cases in the rural community during the second half of the 20th century may be accounted for by increased standards of living generated by economic advancement. Where a decline has not occurred or incidence is unusually high, CHD may be acting as an indicator of social disadvantage. Field trials and control programmes demonstrated that pastoral echinococcosis readily responded to intervention. Indeed, in both New Zealand and Tasmania, using different administrative structures and methods of funding, E. granulosus was driven from endemic towards extinction status. The really convincing result was the rapid decline in CHD in all age groups. The problem still to be solved is to identify methods for eliminating foci where high levels of CHD still exist but, continent- or even state-wide intervention may not be considered to be cost-effective using current tools. Here, mathematical modelling and cost-benefit analysis can be regarded as powerful methods to assist the decision-making process. 相似文献
14.
Ricardo A. Godoy Elizabeth Goodman Richard Levins Mariana Caram Craig Seyfried 《Economics & Human Biology》2007,5(1):82-99
The links between adult height and socioeconomic-political marginality are controversial. We test hypotheses by comparing secular trends between two groups of USA adult male citizens born during 1886-1930: (a) 9805 men surveyed in Puerto Rico during 1965 and (b) 3064 non-Hispanic Whites surveyed on the mainland during 1971-1975. Puerto Rico provides an apt case study because it is the oldest colony in the world and was the poorest region of the USA during the 20th century. During the period considered the average adult man in Puerto Rico was 164.8 cm tall, 8.3 cm shorter than the average adult man on the mainland (173.1cm). Both groups experienced secular improvements in height, with men on the mainland having higher rates than men in Puerto Rico. In neither case were results statistically significant. The modest changes in Puerto Rico likely reflect the offsetting role of improved health and a stagnant rural economy during the first half of the 20th century. 相似文献
15.
G. I. El’chinova I. M. Hidiyatova I. G. Terechovskaia E. K. Khusnutdinova R. A. Zinchenko 《Russian Journal of Genetics》2007,43(8):954-956
Data on several populations of Russia have been used to demonstrate that the change in the endogamy index detected in the second half of the 20th century is not global. Migration activity remains high in populations with relatively low endogamy indices, and their endogamy does not change with time. In regions with medium and high endogamy indices, these values also tend to remain stable. The endogamy indices of urban populations are increasing, and those of rural populations are decreasing. 相似文献
16.
El'chinova GI Khidiiatova IM Terekhovskaia IG Khusnutdinova EK Zinchenko RA 《Genetika》2007,43(8):1146-1148
Data on several populations of Russia have been used to demonstrate that the change in the endogamy index detected in the second half of the 20th century is not global. Migration activity remains high in populations with relatively low endogamy indices, and their endogamy does not change with time. In regions with medium and high endogamy indices, these values also tend to remain stable. The endogamy indices of urban populations are increasing, and those of rural populations are decreasing. 相似文献
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