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"The article deals with the history and the geography of migration in the Hapsburg Empire in the year 1910. It describes the size, the spatial diffusion, and the demographic and social structure of different types of migration: internal migration, emigration, and immigration." (SUMMARY IN ENG)
Tibet, a most beautiful place, locating in southwestern China. She has been called as the third pole of the earth. Unique geological history, complex land surface and climatic zones, various soil types, all different wild vegetations etc., all of these make Tibet a very typical area of vertical agricultural ecosystem. The ecosystem in Tibet may be the most complex in the world, which varies from place to place. Genetic differentiation of 107 accessions of Brassica rapa from Tibet plateau was studied by DNA PAPD analysis using 2210 bp random primers, the genetical distribution in 107 accession of Brassica rapa from Tibet plateau was found. The results are as follows: (1) Total 236 bands were produced from 107 Tibet oilseed accession of B. rapa germaplasm resource in Tibet, of 210 bands amplified from B. rapa germaplasm resource showed polymorphism, with the ratio 88.98%. The result showed that oilseed accession of B. rapa in Tibet has richer genetic diversity; (2) Dendrogram constructed from DNA RAPDs showed that 107 accessions of B. rapa from Tibet plateau were divided into 11 cluster by calculating genetic distance, the cluster analysis showed that the genetic variation among oilseed accessions of B. rapa was closely related with their eco-geographic distribution; extensive variation existed among the accessions from Tibet Province. Based on the analysis of unique geological history, complex land surface and climatic zones, various soil types, complex growing environments, long agricultural history, different cropping systems, and natural and artificial selection as well as plant geography, plant evolution theory, it concludes that Tibet is one of the oil seed gene centers in the word.
Malignant tumours are encountered among all races and in every type of geographical zone, but there are marked differences in different areas in the prevalence of particular forms of tumour-differences that are to a greater or lesser extent dependent on factors such as the climate and geography of the region and the habits, customs and occupations of the people. The study of these factors in relation to the occurrence of malignant tumours is of great importance in reaching an understanding of the etiology of tumours in man.In this paper the author discusses the many problems involved in the study of regional features in the prevalence of malignant tumours, with special reference to the difficulties of ensuring comparability of the data from widely differing regions and population groups. He concludes the paper with a review of some known facts regarding the distribution of malignant tumours at various sites in which he compares data obtained in surveys in the USSR with those obtained in other countries.
Many factors are jointly involved in the changes in the epidemiological and clinical expressions of dengue fever, an arbovirus transmitted by Aedes mosquitoes. In the past forty years, this disease has spread throughout the tropical region, well beyond its original home in Southeast Asia. In some geographic areas, it now appears in a severe haemorrhagic form that requires specialized medical treatment. Many of its mechanisms and features depend on the etiologic agent, human host, and vectors as well as upon bioecologic and socioeconomic factors. Its epidemiological cycles are accordingly quite complex. The threat associated with three current transformations--its geographic extension, epidemiological changes, and aggravation of clinical symptoms--requires an approach that integrates geography and pathology. Such an analysis should provide tools to answer some of the riddles (i.e. specify the epidemiogenic geosystem) by sketching various combinations of factors that reflect the emergence of the disease in specific areas and play a role in its spread from one epidemic area to another. This synthesis about the diverse mutations of the disease calls for a methodical comparison by geographic characteristics and population groups.
The impact of geography on incidence of clinical episodes of malaria was investigated in a cohort of children enrolled in a longitudinal clinical trial of antimalarial therapy in Kampala, Uganda. Participant households and the boundaries of local swamps and streams were mapped and incidence of clinical malaria episodes was measured prospectively using passive surveillance during one year of follow-up. Of 316 cohort participants, 305 from 219 households were followed for at least six weeks and were included in the analysis. Incidence of clinical malaria was highly variable, with no episodes occurring in 131 participants, and 367 new episodes of malaria diagnosed in the remaining 174 children. A gradient in incidence of clinical episodes of malaria was observed with distance of residence from a swamp (0.41 episodes per person year for residence > 100 meters from a swamp increasing to 2.22 episodes per person year for residence within a swamp), or a stream (0.61 episodes per person year for residence > or = 500 meters from a stream versus 1.76 episodes per person year for residence <500 meters from a stream). Multivariate analysis showed that distances of residence from a swamp or from a stream were independent predictors of malaria incidence, controlling for age, use of preventative measures, and primary source of water. Distance from a swamp was the strongest predictor, with an incidence rate ratio of 4.3 (95% confidence interval = 2.6-6.9, P < 0.001) between residence within a swamp and >100 meters from a swamp. In this urban setting, incidence of clinical episodes of malaria was strongly associated with proximity of residence to potential mosquito breeding sites.
OBJECTIVES: This article presents a profile of variations in disability-free life expectancy (DFLE) by health region. DATA SOURCES: Mortality data for 1995 through 1997 are from the Canadian Vital Statistics Database. Estimates of disability (major activity limitations) and sociodemographic characteristics are based on data from the 1996 Census. Supplementary information was provided by the Demography and Geography divisions at Statistics Canada. ANALYTICAL TECHNIQUES: DFLE was calculated using a modified version of Sullivan's method. Linear regression using 4 factors representing socio-demographic profiles was used to explain the variation of DFLE by health region. These 4 synthetic variables were determined using principal component analysis. MAIN RESULTS: In 1996, DFLE for both sexes was estimated to be 68.6 years. Estimates by health region varied considerably. Socio-economic status explains a high proportion of the variation of DFLE by health region.
BACKGROUND: The centralization of health care services has numerous potential benefits but April compromise access for individuals living in remote areas. OBJECTIVES: To examine the association between a patient's place of residence and the likelihood of undergoing a coronary revascularization procedure within one year after cardiac catheterization. METHODS: All Alberta residents undergoing cardiac catheterization between 1995 and 1998 were examined. Geographical distance from patient place of residence to a centralized catheterization facility was calculated. The adjusted odds of undergoing cardiac revascularization within one year of catheterization was determined as a function of distance, controlling for differences in patient age, clinical factors and economic status. RESULTS: Of 21816 residents who underwent cardiac catheterization in the province, 10997 had a revascularization procedure. Graphical examination of distance revealed a change in revascularization rates in patients living more than 450 km from revascularization centres. Further analysis was conducted using this cutpoint. Patients living in these remote areas were more likely to undergo a coronary revascularization procedure within the next year (adjusted odds ratio 1.65, 95% CI 1.05 to 2.59). However, these same residents were also less likely to undergo catheterization in the first place when compared with other Albertans (270 versus 398 procedures per 100000 population). CONCLUSION: Only a small proportion of the population living in Alberta's most remote areas were more likely to undergo a revascularization procedure, indicating a remarkable uniformity of access to revascularization after coronary cardiac catheterization has occurred. This study examines the use of an existing database to gain further insights into the relationship between geography and access to cardiac care, and the distance-access relationship for coronary revascularization in Alberta.
The view of the spatial structure of the geomerida (Earth's life cover) as a continuum that prevails in modern phytocoenology is mostly determined by a physiognomic (landscape-bionomic) discrimination of vegetation components. In this connection, geography of life forms appears as subject of the landscapebionomic biogeography. In zoocoenology there is a tendency of synthesis of alternative concepts based on the assumption that there are no absolute continuum and absolute discontinuum in the organic nature. The problem of continuum and discontinuum of living cover being problem of scale aries from fractal structure of geomerida. This problem arises from fractal nature of the spatial structure of geomerida. The continuum mainly belongs to regularities of topological order. At regional and subregional scale the continuum of biochores is rather rare. The objective evidences of relative discontinuity of the living cover are determined by significant alterations of species diversity at the regional, subregional and even topological scale Alternatively to conventionally discriminated units in physionomically continuous vegetation, the same biotic complexes, represented as operational units of biogeographical and biocenological zoning, are distinguished repeatedly and independently by different researchers. An area occupied by certain flora (fauna, biota) could be considered as elementary unit of biotic diversity (elementary biotic complex).
The following study compares the distribution of surnames in the populations of Western Slovenian municipalities, which were part of the Italian state until the end of the Second World War. The analyses have been carried out firstly by assessing the similarity of different populations to one another so as to verify possible aggregations; secondly, by figuring these relationships of similarity in a representation through unrooted tree (NJ); finally, by applying spatial autocorrelation to the distribution of surnames in the territory so as to highlight possible processes in the diffusion of people in the area under examination. On the whole, it seems likely that the population living in the area is geographically quite stable, although some differences may be noted depending both on the geography of the territory, particularly in the northern part, and on peculiar historical and socioeconomic conditions, which at the same time have characterized and modified the demographic structure of some of these municipalities.
Wild waterfowl and shorebirds are known to be the natural reservoir for influenza A viruses. Surveillance studies in waterfowl and shorebirds in North America show that influenza A viruses are repeatedly recovered from these birds. However, the virus recovery is influenced by geography, season, age and species of birds. In addition to the natural reservoir, the live-bird marketing system (LBMS) in certain regions of the United States has been recognized as a man-made reservoir of influenza viruses and has been linked to several outbreaks of low pathogenicity avian influenza (LPAI) in poultry. Outbreaks of LPAI in commercial poultry is attributed to movement of infected birds, dirty or improperly cleaned crates, and contaminated vehicles from the LBMS to poultry farms. However, in the majority of outbreaks in poultry, the source of infection is suspected to be wild aquatic birds or the source is unknown. Since 2002, three outbreaks of highly pathogenic avian influenza (HPAI) have occurred in the Americas; one each in Chile (H7N3), United States (H5N2), and Canada (H7N3). In each of these outbreaks, a precursor virus of low pathogenicity mutated to become highly pathogenic after circulating in poultry. The HPAI viruses recovered from the three outbreaks had unique molecular and phenotypic characteristics that do not conform to other known HPAI viruses. These findings emphasize the need for monitoring wild and domestic bird species for presence of influenza A viruses.
INTRODUCTION: A recent study has shown that the national-scale difference in immunization coverage between non-Hispanic white (abbreviated "white") and non-Hispanic African-American (abbreviated "African-American") children aged 19-35 months in the United States has increased by about 1 percentage point annually. We examined how this widening gap differs with geography and income. METHODS: We used data from the National Immunization Survey, 1998-2003, a national telephone survey. We examined differences between white and African-American children in immunization coverage within income groups (at or above versus below the federal poverty level) for each census region (northeast, south, midwest and west). We tested the hypothesis of constant disparity over time. RESULTS: Among households at or above the federal poverty level in the northeast census region, disparity is widening (white coverage minus African-American coverage was -0.5 in 1998 but 15.5 in 2003). Among household at or above the federal poverty level in the midwest census region, disparity is narrowing (white coverage minus African-American coverage was 13.9 in 1998 but 2.5 in 2003). We found no significant evidence of a trend in other groups. CONCLUSIONS: Widening national-level disparity in immunization coverage is primarily attributable to trends in the northeast census region. Addressing the widening disparity in coverage requires new strategies that consider current social and economic contexts.
BACKGROUND: Gambling is a risky behaviour that involves uncertain financial outcomes, can be addictive, and has been associated with strongly adverse social and public health outcomes. We wanted to assess whether socio-economic and gambling-related-opportunity environments of neighbourhoods affected the uptake of video lottery terminal (VLT) gambling among Montréal youth. METHODS: Spatial and statistical analyses were conducted to examine geographical patterns of neighbourhood socio-economic conditions, VLT sites (n=407), and high school locations (n=305) within the Montréal Census Metropolitan Area (CMA). VLT concentration within high school neighbourhoods was measured to examine how the number of VLT opportunities varies according to socio-economic status of the school neighbourhood. A student survey was analyzed using logistic regression analysis to explore the role of individual (student) characteristics and environmental (neighbourhood) characteristics in predicting the VLT gambling behaviours reported among a sample (n=1206) of high school students. RESULTS: Video lottery gambling opportunities are more prevalent near schools located in socio-economically deprived neighbourhoods compared with schools located in more affluent neighbourhoods. The principal individual risk factors for VLT gambling were shown to be male sex, peer VLT-use, substance use, as well as the after-school routines of youth. INTERPRETATION: The spatial distribution of VLTs reflects local geographies of socio-economic disadvantage and may have a pronounced impact on students attending schools in lower income neighbourhoods, especially those with individual risk factors. Efforts to reduce gambling-related public health costs may want to take into account the socio-spatial distribution of gambling opportunities, particularly in the local environments that youth frequent.
Anastrepha suspensa (Loew) is an economically important pest, restricted to the Greater Antilles and southern Florida. It infests a wide variety of hosts and is of quarantine importance in citrus, a multi-million dollar industry in Florida. The observed recent increase in citrus infested with A. suspensa in Florida has raised questions regarding host-specificity of certain populations and genetic diversity of the pest throughout its geographical distribution. Cytochrome oxidase I (COI) DNA sequence data was used to characterize the genetic diversity of A. suspensa from Florida and Caribbean populations reared from different host plants. Maximum likelihood and Bayesian phylogenetic methods were used to analyse COI data. Sequence variation among mitochondrial COI genes from 107 A. suspensa samples collected throughout Florida and the Caribbean ranged between 0 and 10% and placed all A. suspensa as a monophyletic group that united all A. suspensa in a clade sister to a Central American group of the A. fraterculus paraphyletic species complex. The most likely tree of the COI locus indicated that COI sequence variation was too low to provide resolution at the subspecies level, therefore monophyletic groups based on host-plant use, geography (Florida, Jamaica, Cayman Islands, Puerto Rico or Dominican Republic) or population sampled are not supported. This result indicates that either no population segregation has occurred based on these biological or geographical distinctions and that this is a generalist, polyphagous invasive genotype. Alternatively, if populations are distinct, the segregation event was more recent than can be distinguished based on COI sequence variation.
Research themes of interest to both clinical and social sciences have been proliferating in recent years. While the personal experiences of individuals who conduct interdisciplinary research probably vary widely, several general models of research and its conduct seem to be quite common. This is illustrated using the author's personal experiences, beginning from his disciplinary roots in medical geography.
The environmental factors including geography, geology and soil have been reviewed in areas of high prevalence of non-filariasis endemic elephantiasis surveyed in tropical Africa. These areas occur at altitudes above 1000 m where rainfall is seasonal and exceeds 1000 mm annually. The soil is a red clay, very slippery when wet and very adhesive if allowed to dry on the skin. These are also areas of past or present alkalic volcanism, the prevalence being highest in proximity to the volcanoes. The derived soils are notable for the high proportion of alumino-silicate particles of colloid size in the clays. The significance of these findings suggests that the number and small size of the clays. The significance of these findings suggests that the number and small size of the particles facilitates entry through the skin into the lymphatic tissues, where they exert the known irritant and fibrosing effects of silica and alumina.
In 1958, a cancer registry was established in Papua New Guinea for a population of 2 million who had remained in near isolation for millenia until recently. This report includes cancer data for 1970 through 1978. During those years, the registrations increased from 200 to 600. The reasons for this increase and the patterns of reporting over the entire 21-year period are examined. The data offered us opportunities to examine changes in case findings according to geography, time, and sex. Genuine differences in cancer incidence and pattern within this diverse country, mainly between the highland and lowland regions, were studied, particularly concerning oral, skin, liver, and penile cancers, and Burkitt's lymphoma. The controversy remains over the relationship of oral cancer and chewing of substances other than tobacco; but in this country, at least, a chew consisting only of areca nut mixed with lime must be held suspect. With the emergence from isolation, profound socioeconomic changes are occurring in this country; the patterns of cancer must change also, and we may be seeing the beginning of this already. Possible fruitful areas for further detailed studies are indicated.
Transformations of computer maps of geographical distribution of gene frequencies using basic mathematical statistical procedures are considered. These transformations are designated as statistical transformation of maps. Two transformation groups are considered: of one map separately and of a group of maps. Transformations possess a value beyond their use as intermediate stages of more complicated cartographical analysis: the resulting maps carry entirely new information on the geography of genes or a gene pool. This article considers three examples of obtaining new genetic profiles using statistical transformation algorithms. These profiles are of: heterozygosity (of HLA-A, B, C loci in northeastern Eurasia); (2) disease risk (Rh-incompatibility of mother and child with simultaneous registration of Rh and ABO blood groups in Eastern Europe); (3) genetic distances (from own mean ethnic values for Belarus' and from mean Russian values for the gene pool of Eastern Europe).
The marshlands of coastal southern and eastern England had unusually high levels of mortality from the sixteenth to the nineteenth century. The unhealthiness of the environment aroused frequent comment during this period and it was attributed to an endemic disease known as "marsh fever" or "ague". Marsh parishes were perceived both as a danger to the local inhabitants and as a deterrent to potential settlers. This paper traces the geography and history of the "marsh fever" in England and shows that the disease was, in fact, malaria transmitted by anopheline mosquitoes. Malaria, once endemic in the coastal marshes of England, had a striking impact on local patterns of disease and death. Yet this study also suggests that the species of malaria endemic in England were vivax and malariae and not the tropical strains of P. falciparum. The paper outlines a number of ways in which "benign" forms of malaria, acting either directly or indirectly, as well as in conjunction with other factors, could have given rise to the unusually high death rates experienced in early modern marshland England. The discussion concludes with an examination of the reasons for the clinical disappearance of malaria during the nineteenth century, its reappearance after the First and Second World Wars and the problem of imported malaria in Britain today.