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1.
We analyzed the evolution of height in Colombia of cohorts born in the period 1965–1990 by ethnic groups. We found that Afro-Colombian men and women were the tallest: 6 cm taller than indigenous people and 2 cm taller than the rest of the population. We also found that the height gap between Afro-Colombians and others decreased during the period under study by 0.7 cm for both men and women. While improvements were noticeable among the Afro-Colombians and those who chose not to be classified by ethnicity, in the case of the indigenous population only female cohorts registered an average-height increase of 1.5 cm. Moreover, we found that indigenous Colombians were more likely than other ethnic groups to experience an increase in biological well-being as a consequence of an improvement in their socio-economic status, thereby reducing the average-stature gap between them and the rest of the population by 2.1 and 3.6 cm for men and women, respectively.  相似文献   

2.
Abstract

Both breastfeeding initiation and duration increased in Peru during 1977–86. Although one would have expected that the average incidence and duration of breastfeeding would have declined as a result of changes in population characteristics, the potential for an overall decline was more than overcome by changes in behavior. A net increase in initiation and duration is shown for all subgroups of interest. The largest absolute increases are documented for children who, in 1977, were the least likely to be breastfed and who were breastfed for the shortest durations.  相似文献   

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Understanding the current epidemiologic dynamic of tuberculosis (TB) in any society requires a holistic approach. In the current paper, the history and behavior of the TB is summarized for Bogotá, Colombia. In prehispanic periods the occurrence of TB was low. During the Conquest and the Colony periods, a moderate increase of pulmonary and abdominal TB was observed. In the 1870s, a great increase in cases of pulmonary TB was associated with the accelerated urbanization process. Since the 1920s, the occurrence of pulmonary TB shifted to the status of an endemic disease. After 1920, its occurrence was relatively steady until the 1970s, when its occurence greatly decreased. More recently, however, an increase in case numbers has been observed. The occurrence of TB in each period is associated with clearly defined social and environmental phenomena.  相似文献   

5.
In Peru, it was hypothesized that epidemic cholera in 1991 was linked to El Niño, the warm phase of El Niño–Southern Oscillation. While previous studies demonstrated an association in 1997–1998, using cross-sectional data, they did not assess the consistency of this relationship across the decade. Thus, how strong or variable an El Niño–cholera relationship was in Peru or whether El Niño triggered epidemic cholera early in the decade remains unknown. In this study, wavelet and mediation analyses were used to characterize temporal patterns among El Niño, local climate variables (rainfall, river discharge, and air temperature), and cholera incidence in Piura, Peru from 1991 to 2001 and to estimate the mediating effects of local climate on El Niño–cholera relationships. The study hypothesis is that El Niño-related connections with cholera in Piura were transient and interconnected via local climate pathways. Overall, our findings provide evidence that a strong El Niño–cholera link, mediated by local hydrology, existed in the latter part of the 1990s but found no evidence of an El Niño association in the earlier part of the decade, suggesting that El Niño may not have precipitated cholera emergence in Piura. Further examinations of cholera epicenters in Peru are recommended to support these results in Piura. For public health planning, the results may improve existing efforts that utilize El Niño monitoring for preparedness during future climate-related extremes in the region.  相似文献   

6.
Urban growth reduces open space in and around cities, impacting biodiversity and ecosystem services. Using land-cover and population data, we examined land consumption and open space loss between 1990 and 2000 for all 274 metropolitan areas in the contiguous United States. Nationally, 1.4 million ha of open space was lost, and the amount lost in a given city was correlated with population growth (r(272) = 0.85, P<0.001). In 2000, cities varied in per capita land consumption by an order of magnitude, from 459 m2/person in New York to 5393 m2/person in Grand Forks, ND. The per capita land consumption (m2/person) of most cities decreased on average over the decade from 1,564 to 1,454 m 2/person, but there was substantial regional variation and some cities even increased. Cities with greater conservation funding or more reform-minded zoning tended to decrease in per capita land consumption more than other cities. The majority of developed area in cities is in low-density neighborhoods housing a small proportion of urban residents, with Gini coefficients that quantify this developed land inequality averaging 0.63. Our results suggest conservation funding and reform-minded zoning decrease per capita open space loss.  相似文献   

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8.
The Alyki wetland in northern Greece is a site of notable herpetological and ornithological importance. A large population of the tortoise Testudo hermanni began to recover slowly (r = 0.016) between 1990 and 1999, following catastrophic habitat destruction in 1980 and slow decline from 1980–1990. Heathland vegetation showed signs of desiccation, probably due to increased drainage by the salt works, including deterioration of Crataegus, Ruscus and Asphodelus, and loss of formerly important food plants of tortoises. Activity and body mass condition of tortoises were reduced in summer in grassy heath habitats. Predation of artificial (chicken egg) tortoise nests increased, and the relative frequency of juveniles (about 1 % of samples) was lower than after severe habitat destruction or pesticide damage. These changes were attributed to an increasing population of badgers, Meles meles. Population levels of waders were lower in 1998/1999 than in 1988/1989, especially avocets (Recurvirostra avosetta) for which the site was internationally important. Breeding populations of most waders and larids also declined. Mediterranean gulls, for which Alyki was formerly the most important breeding area outside Russia, did not nest from 1990 to 1998, and nests were unsuccessful in 1999. Changes in breeding populations were due to falling lagoon levels, exposure to predators and vegetation encroachment on islet breeding sites. Midwinter waterfowl populations remained high or increased, however, as alternative feeding areas were available in the lagoon. Preservation of the habitats against development of the salt works and increasing desiccation are necessary to maintain the long-term conservation value of the Alyki site.  相似文献   

9.
Changes in climate and land use, caused by socio-economic changes, greenhouse gas emissions, agricultural policies and other factors, are known to affect both natural and managed ecosystems, and will likely impact on the European terrestrial carbon balance during the coming decades. This study presents a comprehensive European Union wide (EU15 plus Norway and Switzerland, EU*) assessment of potential future changes in terrestrial carbon storage considering these effects based on four illustrative IPCC-SRES storylines (A1FI, A2, B1, B2). A process-based land vegetation model (LPJ-DGVM), adapted to include a generic representation of managed ecosystems, is forced with changing fields of land-use patterns from 1901 to 2100 to assess the effect of land-use and cover changes on the terrestrial carbon balance of Europe. The uncertainty in the future carbon balance associated with the choice of a climate change scenario is assessed by forcing LPJ-DGVM with output from four different climate models (GCMs: CGCM2, CSIRO2, HadCM3, PCM2) for the same SRES storyline. Decrease in agricultural areas and afforestation leads to simulated carbon sequestration for all land-use change scenarios with an average net uptake of 17–38 Tg C/year between 1990 and 2100, corresponding to 1.9–2.9% of the EU*s CO2 emissions over the same period. Soil carbon losses resulting from climate warming reduce or even offset carbon sequestration resulting from growth enhancement induced by climate change and increasing atmospheric CO2 concentrations in the second half of the twenty-first century. Differences in future climate change projections among GCMs are the main cause for uncertainty in the cumulative European terrestrial carbon uptake of 4.4–10.1 Pg C between 1990 and 2100.  相似文献   

10.

Background

Cysticercosis is caused by the invasion of human or pig tissues by the metacestode larval stage of Taenia solium. In Europe, the disease was endemic in the past but the autochthonous natural life cycle of the parasite is currently completed very rarely. Recently, imported cases have increased in parallel to the increased number of migrations and international travels. The lack of specific surveillance systems for cysticercosis leads to underestimation of the epidemiological and clinical impacts.

Objectives

To review the available data on epidemiology and management of cysticercosis in Europe.

Methods

A review of literature on human cysticercosis and T. solium taeniasis in Europe published between 1990–2011 was conducted.

Results

Out of 846 cysticercosis cases described in the literature, 522 cases were autochthonous and 324 cases were imported. The majority (70.1%) of the autochthonous cases were diagnosed in Portugal from 1983 and 1994. Imported cases of which 242 (74.7%) diagnosed in migrants and 57 (17.6%) in European travellers, showed an increasing trend. Most of imported cases were acquired in Latin America (69.8% of migrants and 44.0% of travellers). The majority of imported cases were diagnosed in Spain (47.5%), France (16.7%) and Italy (8.3%). One third of neurosurgical procedures were performed because the suspected diagnosis was cerebral neoplasm. Sixty eight autochthonous and 5 imported T. solium taeniasis cases were reported.

Conclusions

Cysticercosis remains a challenge for European care providers, since they are often poorly aware of this infection and have little familiarity in managing this disease. Cysticercosis should be included among mandatory reportable diseases, in order to improve the accuracy of epidemiological information. European health care providers might benefit from a transfer of knowledge from colleagues working in endemic areas and the development of shared diagnostic and therapeutic processes would have impact on the quality of the European health systems.Key words: cysticercosis, neurocysticercosis, Taenia solium, taeniasis, Europe, travellers, migrants.  相似文献   

11.
Atmospheric pollen was collected with a Burkard spore trap in Ankara, Turkey, from January 1990 to January 1993. A total of 135.787 grains/m3 belonging to 47 taxa were observed. The local pollen season started in February in 1990 and 1991 and in March in 1992. Relatively low pollen concentrations were recorded in 1990 and 1992, probably because of precipitation and low wind speed in the spring. A relatively high pollen concentration was recorded in 1991 which could be caused by higher wind speed in the spring and more precipitation during the winter. Cupressaceae/Taxaceae, Pinaceae, Gramineae, Betula, Moraceae, Platanus, Populus, Acer, Quercus, Chenopodiaceae/Amaranthaceae, Plantago, Rumex are found to be the dominant pollen types in the atmosphere in Ankara. The pollen composition generally reflects the vegetation of gardens, parks and roadsides, while the natural steppe vegetation of the area around Ankara is not properly represented.  相似文献   

12.
Aim To estimate relative contribution and time trends of HPV types in cervical cancer in Cali, Colombia over a 50 years’ period.MethodsParaffin blocks of 736 cervical cancer histological confirmed cases were retrieved from the pathology laboratory at Hospital Universitario del Valle (Cali, Colombia) and HPV genotyped using SPF10-PCR/DEIA/LiPA25 (version 1) assay. Marginal effect of age and year of diagnosis in secular trends of HPV type prevalence among HPV+ cases were assessed by robust Poisson regression analysis.Results64.7% (95%CI: 59.9–69.2) of squamous cell carcinomas (SCCs) were attributed to HPV 16 and 18, 78.2% (95%CI: 74–82) to HPV 16, 18, 31, 33 and 45 and 84.8% (95%CI: 81–88.1) to HPV 16, 18, 31, 33, 45, 52 and 58 while ninety-three percent of adenocarcinomas (ADCs) were attributed to HPV 16, 18 and 45 only. The prevalence of specific HPV types did not change over the 50-year period. A significant downward trend of prevalence ratios of HPV16 (​P = 0.017) and α7 but HPV 18 (i.e., HPV 39, 45, 68, 70, ​P = 0.024) with increasing age at diagnosis was observed. In contrast, the prevalence ratio to other HPV genotypes of α9 but HPV 16 genotypes (i.e., HPV 31, 33, 35, 52, 58, 67, ​P = 0.002) increased with increasing age at diagnosis.ConclusionNo changes were observed in the relative contribution of HPV types in cervical cancer in Cali, Colombia during the 50 years. In this population, an HPV vaccine including the HPV 16, 18, 31, 33, 45, 52 and 58 genotypes may have the potential to prevent ∼85% and 93% of SCC and ADC cases respectively.  相似文献   

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14.
Linusson  A.-C.  Berlin  G. A. I.  Olsson  E. G. A. 《Plant Ecology》1998,136(1):77-94
Two data sets, one from the 1960s and one from 1990, from continuously managed semi-natural meadows (semi-natural grasslands used for hay-cutting) in Småland, southern Sweden, were analysed to describe the vegetation and in an attempt to characterise changes that have occurred in the vegetation. Based on a classification of the data set, nine plant communities were recognised. The main vegetational differences, as revealed by an ordination, were due to variation in soil moisture, which ranged from wet to dry.During the investigation period, the amount of hay meadow area decreased, particularly the area of wet-moist meadows. In addition, the total variation in the vegetation diminished, and three plant communities more or less disappeared. The turnover index of species in the data set was 36%, and most of the species that were lost had initially been uncommon. Lost species included rare taxa, such as Gentianella campestris and Linum catharticum, while the new species tended to be common in the region. Annual and biennial species accounted for a greater proportion of the lost taxa than did perennial species. The mean cover of species per plot and the relative abundance of graminoids per plot increased.The recorded changes in the vegetation may be related to the increased loads of nitrogen pollutants as well as to a decrease in management intensity. The diminished area is related to changes in land-use. The meadow sites in Småland have been part of a landscape rich in grasslands, but today they have a more or less relict status. They differ from grasslands found elsewhere in Sweden and Scandinavia. In Sweden, the majority (68%) of endangered vascular plants belong to the agricultural landscape. To ensure the survival of individual species it is important to preserve all types of meadows, not only a few selected ones, since no two meadows are alike.  相似文献   

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Malaria is still a primary health problem in Colombia. The locality of Tierradentro is situated in the municipality of Montelíbano, Córdoba, in the northwest of Colombia, and has one of the highest annual parasite index of malaria nationwide. However, the vectors involved in malaria transmission in this locality have not yet been identified. In this study, the local anthropophilic Anopheles composition and natural infectivity with Plasmodium were investigated. In August 2009, 927 female Anopheles mosquitoes were collected in eight localities using the human landing catch method and identified based on their morphology. Cryptic species were determined by restriction fragment length polymorphism-internal transcribed spacer (ITS)2 molecular analysis. Eight species [Anopheles nuneztovari s.l. (92.8%), Anopheles darlingi (5.1%), Anopheles triannulatus s.l. (1.8%), Anopheles pseudopunctipennis s.l. (0.2%), Anopheles punctimacula s.l. (0.2%), Anopheles apicimacula (0.1%), Anopheles albimanus (0.1%) and Anopheles rangeli (0.1%)] were identified and species identity was confirmed by ITS2 sequencing. This is the first report of An. albimanus, An. rangeli and An. apicimacula in Tierradentro. Natural infectivity with Plasmodium was determined by ELISA. None of the mosquitoes was infectious for Plasmodium. An. nuneztovari s.l. was the predominant species and is considered the primary malaria vector; An. darlingi and An. triannulatus s.l. could serve as secondary vectors.  相似文献   

18.
Papers given at the Symposium on Mammalian Radiation Genetics are summarized and discussed under three headings: (i) those helping to bridge the gap between what we know about genetic damage in the mouse and what we need to know in man; (ii) analytical studies on mice; (iii) assessment of genetic hazards from various sources.  相似文献   

19.

Background

India, with a population of more than 1.21 billion, has the highest maternal mortality in the world (estimated to be 56000 in 2010); and adolescent (aged 15–19) mortality shares 9% of total maternal deaths. Addressing the maternity care needs of adolescents may have considerable ramifications for achieving the Millennium Development Goal (MDG)–5. This paper assesses the socioeconomic differentials in accessing full antenatal care and professional attendance at delivery by adolescent mothers (aged 15–19) in India during 1990–2006.

Methods and Findings

Data from three rounds of the National Family Health Survey of India conducted during 1992–93, 1998–99, and 2005–06 were analyzed. The Cochran-Armitage and Chi-squared test for linear and non-linear time trends were applied, respectively, to understand the trend in the proportion of adolescent mothers utilizing select maternity care services during 1990–2006. Using pooled multivariate logistic regression models, the probability of select maternal healthcare utilization among women by key socioeconomic characteristics was appraised. After adjusting for potential socio-demographic and economic characteristics, the likelihood of adolescents accessing full antenatal care increased by only 4% from 1990 to 2006. However, the probability of adolescent women availing themselves of professional attendance at delivery increased by 79% during the same period. The study also highlights the desolate disparities in maternity care services among adolescents across the most and the least favoured groups.

Conclusion

Maternal care interventions in India need focused programs for rural, uneducated, poor adolescent women so that they can avail themselves of measures to delay child bearing, and for better antenatal consultation and delivery care in case of pregnancy. This study strongly advocates the promotion of a comprehensive ‘adolescent scheme’ along the lines of ‘Continuum of Maternal, Newborn and Child health Care’ to address the unmet need of reproductive and maternal healthcare services among adolescent women in India.  相似文献   

20.
In the period 1875–1920, a debate about the generality and applicability of evolutionary theory to all organisms was motivated by work on unicellular ciliates like Paramecium because of their peculiar nuclear dualism and life cycles. The French cytologist Emile Maupas and the German zoologist August Weismann argued in the 1880s about the evolutionary origins and functions of sex (which in the ciliates is not linked to reproduction), and death (which appeared to be the inevitable fate of lineages denied sexual conjugation), an argument rooted in the question of whether the ciliates and their processes where homologous to other cellular organisms. In the beginning of the twentieth century, this question of homology came to be less important as the ciliates were used by the British protozoologist Clifford Dobell and the American zoologist Herbert Spencer Jennings to study evolutionary processes in general rather than problems of development and cytology. For them, homology mattered less than analogy. This story illustrates two partially distinct problems in evolutionary biology: first, the question of whether all living things have common features and origins; and second, whether their history and current nature can be described by identical mechanisms. Where Maupas (contra Weismann) made the ciliates qualitatively the same as all other organisms in order to create a cohesive evolutionary theory for biology, Jennings and Dobell made them qualitatively different in order to achieve the same end. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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