首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
During the last decades, farmland habitats in central European countries have changed significantly, seriously affecting populations of many farmland bird species. We compiled available published data on densities of three owl species, Athene noctua, Asio otus and Strix aluco collected in the Polish farmland. All results of censuses based on the playback method conducted between 1980–2005 were included in the analysis. The proportions of grassland, fields, built-up land and forest at each studied plot were estimated and used as predictors in additive models. Proportions of main land use types, extracted with the principal component analysis, explained much of the variation found in owl densities, although some of the relationships were nonlinear. In general, owl densities were found to be affected positively by a high percentage of grasslands and built-up land, and negatively by the amount of fields and forests. Little owl densities showed a significant negative trend over the study period. It seems that high prey availability is an important factor accounting for the positive relationship between grassland proportion and owl density. The significant decrease in grassland areas and increase in forest coverage that were recently recorded in Poland may thus negatively affect populations of the three owl species studied here.  相似文献   

2.
3.
BackgroundThe Hungarian National Cancer Registry (HNCR) was legally established as a population-based cancer registry in 1999, and its operation started in 2000 supporting the planning and development of the Hungarian oncology network as well as informing national cancer control policies. Ensuring comparable, accurate, and complete data on malignant and in situ neoplasms is critical in determining the applicability of the database. The aim of this study was to perform a comprehensive evaluation of the data quality at the HNCR.MethodsBased on qualitative and semiquantitative methods from current international guidelines, we assess the comparability, completeness, validity, and timeliness of the collected data over the diagnostic period 2000–2019, with a focus on the year 2018.ResultsCoding practices and the classification system used at the HNCR are based on the International Classification of Diseases (ICD-10), which differs from the internationally recommended ICD-O. The annual trends in incidence did not indicate major fluctuations, that may have resulted from data collection discrepancies, while comparisons of the mortality-to-incidence ratio (M:I) compared with 1 minus 5-year observed survival indicated some systematic differences requiring further exploration. The age-standardized (European standard) incidence rate per 100 000 measured by the HNCR in 2018 was very high: 647.9 for men and 501.6 for women, 11.6% and 14.6% higher than the International Agency for Research on Cancer (IARC) estimates respectively. Behind the overall differences between the two data sources, we identified that the vast majority were due to ill-defined ICD codes: malignant neoplasm of other and ill-defined sites (C76), and malignant neoplasm without specification of site (C80). Otherwise, there were no major discrepancies by localization. The proportion of morphologically verified cancer cases was 57.8% overall, that of death certificates was 2.3%, and that of unknown primary tumors was 1.4%.ConclusionFurther implementations and interventions are required to ensure that the operations, coding practices, and the classification system used at the national registry are in accordance with international standards, and to increase the completeness and validity of the collected cancer data. In particular, the low morphologically verified proportion questions the overall accuracy of the stated diagnoses within the database. Nevertheless, our examination implies that the data of the HNCR are reasonably comparable, and without doubt fulfill the requirements to support national oncology services and cancer planning. However, most importantly, a review of registry personnel and resource requirements to run the national population-based cancer registry should be an essential part of Hungary’s national cancer strategy.  相似文献   

4.
Abstract

Cumulative fertility is analyzed for four regions of Mexico, based on World Fertility Survey data of 1976–77: the State of Baja California, the Northwest region, the State of Jalisco, and the Northeast region. Based on stepwise regression methodology, the study compares results for twelve subsamples of married respondents, three age categories by four regions. The dependent variables are children ever born and children ever bom in the last five years. Migration, urban, educational, and occupational variables are included as independent variables. Regression results reveal level of education is the major, and negative, influence on fertility. Other results include specific negative effects for prior occupation, size of place of residence, and childhood place of residence. Fertility effects appear different for migration origin and destination regions, but more similar for younger ages. Effects of migration on fertility are small.  相似文献   

5.
BackgroundAnthrax, a global re-emerging zoonotic disease in recent years is enzootic in mainland China. Despite its significance to the public health, spatiotemporal distributions of the disease in human and livestock and its potential driving factors remain poorly understood.Conclusions/SignificanceAnthrax in China was characterized by significant seasonality and spatial clustering. The spatial distribution of human anthrax was largely driven by livestock husbandry, human density, land cover, elevation, topsoil features and climate. Enhanced surveillance and intervention for livestock and human anthrax in the high-risk regions, particularly on the Qinghai-Tibetan Plateau, is the key to the prevention of human infections.  相似文献   

6.
The stability of aptamer–ligand complexes is probed in nanopore-based dynamic force spectroscopy experiments. Specifically, the ATP-binding aptamer is investigated using a backward translocation technique, in which the molecules are initially pulled through an α-hemolysin nanopore from the cis to the trans side of a lipid bilayer membrane, allowed to refold and interact with their target, and then translocated back in the transcis direction. From these experiments, the distribution of bound and unbound complexes is determined, which in turn allows determination of the dissociation constant Kd ≈ 0.1 mM of the aptamer and of voltage-dependent unfolding rates. The experiments also reveal differences in binding of the aptamer to AMP, ADP, or ATP ligands. Investigation of an aptamer variant with a stabilized ATP-binding site indicates fast conformational switching of the original aptamer before ATP binding. Nanopore force spectroscopy is also used to study binding of the thrombin-binding aptamer to its target. To detect aptamer–target interactions in this case, the stability of the ligand-free aptamer—containing G-quadruplexes—is tuned via the potassium content of the buffer. Although the presence of thrombin was detected, limitations of the method for aptamers with strong secondary structures and complexes with nanomolar Kd were identified.  相似文献   

7.
The goal of this study was to compare the richness and endemism patterns of Mexican species of amphibians and reptiles at different spatial scales. We used the best available dataset of distributional ranges generated from ecological niche models and employed geographically weighted regressions (GWRs) to test whether richness and endemism were related. Patterns were found to vary with the scale used for richness and endemism, and these patterns were not coincident. The results showed that: (1) only relatively coarse spatial scales can address latitudinal patterns in amphibians and reptiles, and, in fine scales, they are related to topographic formations; (2) areas of greatest endemism for amphibians and reptiles are located in the highlands of the central or southern part of the country, although not necessarily in the same specific highlands for both groups; (3) there is a strong average correlation between richness and endemism for both groups, indicating that the same factors contribute to both patterns, but these factors act differentially in terms of regions among amphibians and reptiles; and (4) the scale at which the analysis is conducted is important, and we believe that careful consideration of spatial scale must be undertaken to avoid false conclusions. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 305–316.  相似文献   

8.

Background

Sex differences have been reported in the prognosis of certain cancers. In this study, we investigated whether Korean females display better survival rates compared with male patients for solid tumor sites.

Methods

We analyzed data from the Korean National Cancer Incidence Database from 599,288 adult patients diagnosed with solid cancers between 2005 and 2009. Patients were followed until December 2010. We applied a relative excess risk (RER) model adjusting for year of follow-up, age at diagnosis, and stage at diagnosis.

Results

For all solid cancer sites combined, women displayed an 11% lower risk of death compared to men (RER 0.89; 95% CI 0.88–0.90) after adjusting for year of follow-up, age, stage, and case mix. Women showed significantly lower RERs for the following sites: head/neck, esophagus, small intestine, liver, nasal cavities, lung, bone/cartilages, melanoma of skin, soft tissue, brain and CNS, and thyroid. In contrast, women displayed a poorer prognosis than did men for colorectal, laryngeal, kidney and bladder cancer. However, the survival gaps between men and women narrowed by increase in age; female patients over 75 years of age displayed a 3% higher RER of death compared with males in this age group.

Conclusions

Female cancer patients display an improved survival for the majority of solid tumor sites, even after adjustment for age and stage. Age at diagnosis was the major contributor to the women’s survival advantage.  相似文献   

9.
The US government has simultaneously increased efforts to close its border to unauthorized migrants, and opened the border to increasing flows of tourists from Mexico. In this paper I focus on the experiences of Mexican tourists who are able to freely cross the USA–Mexico border with US visas, given that their unique status as tourists from Mexico is an important element to consider because it organizes their daily lives, their moral understandings, and their experiences across the USA–Mexico border. I show how Global South cosmopolitans from Mexico benefit from class privilege in Mexico, but become legally vulnerable in the USA due to their racialization as Mexicans and lack of citizenship rights. This paper draws on ethnographic data and in-depth interviews collected in the border town of Mexicali, Baja California, Mexico between July 2009 and August 2010.  相似文献   

10.
Improved management of carbon storage by terrestrial biomes has significant value for mitigating climate change. The carbon value of such management has the potential to provide additional income to rural communities and provide biodiversity and climate adaptation co-benefits. Here, we quantify the carbon stores in a 49,300-ha landscape centered on the cloud forest–grassland transition of the high Andes in Manu National Park, Peru. Aboveground carbon densities were measured across the landscape by field sampling of 70 sites above and below the treeline. The forest near the treeline contained 63.4 ± 5.2 Mg C ha−1 aboveground, with an additional 13.9 ± 2.8 Mg C ha−1 estimated to be stored in the coarse roots, using a root to shoot ratio of 0.26. Puna grasslands near the treeline were found to store 7.5 ± 0.7 Mg C ha−1 in aboveground biomass. Comparing our result to soil data gathered by Zimmermann and others (Ecosystems 13:62–74, 2010), we found the ratio of belowground:aboveground carbon decreased from 15.8 on the puna to 8.6 in the transition zone and 2.1 in the forest. No significant relationships were found between carbon densities and slope, altitude or fire disturbance history, though grazing (for puna) was found to reduce aboveground carbon densities significantly. We scaled our study sites to the study region with remote sensing observations from Landsat. The carbon sequestration potential of improved grazing management and assisted upslope treeline migration was also estimated. Afforestation of puna at the treeline could generate revenues of US $1,374 per ha over the project lifetime via commercialization of the carbon credits from gains in aboveground carbon stocks. Uncertainties in the fate of the large soil carbon stocks under an afforestation scenario exist.  相似文献   

11.
ObjectiveThe objectives of this study were to describe the epidemiology of HIV in the United States Air Force (USAF) from 1996 through 2011 and to assess whether socio-demographic characteristics and service-related mobility, including military deployments, were associated with HIV infection.MethodsWe conducted a retrospective cohort analysis of USAF personnel who were HIV-infected during the study period January 1, 1996 through December 31, 2011 and a matched case-control study. Cases were USAF personnel newly-diagnosed with HIV during the study period. Five randomly-selected HIV-uninfected controls were matched to each case by age, length of service, sex, race, service, component, and HIV test collection date. Socio-demographic and service-related mobility factors and HIV diagnosis were assessed using conditional logistic regression.ResultsDuring the study period, the USAF had 541 newly diagnosed HIV-infected cases. HIV incidence rate (per 100,000 person-years) among 473 active duty members was highest in 2007 (16.78), among black/ African-American USAF members (26.60) and those aged 25 to 29 years (10.84). In unadjusted analysis restricted to personnel on active duty, 10 characteristics were identified and considered for final multivariate analysis. Of these single (adjusted odds ratio [aOR], 8.15, 95% confidence interval [CI] 5.71–11.6) or other marital status (aOR 4.60, 95% CI 2.72–7.75), communications/ intelligence (aOR 2.57, 95% CI 1.84–3.60) or healthcare (aOR 2.07, 95% CI 1.28–3.35) occupations, and having no deployment in the past 2 years before diagnosis (aOR 2.02, 95% CI 1.47–2.78) conferred higher odds of HIV infection in adjusted analysis.ConclusionThe highest risk of HIV infection in the USAF was among young unmarried deployment-naïve males, especially those in higher risk occupation groups. In an era when worldwide military operations have increased, these analyses identified potential areas where targeted HIV prevention efforts may be beneficial in reducing HIV incidence in the USAF military population.  相似文献   

12.
Howard S. Irwin 《Brittonia》1996,48(3):365-371
Memories of employment at The New York Botanical Garden between 1960 and 1980 are given.  相似文献   

13.
BackgroundIn Taiwan, around 1,500 cases of dengue fever are reported annually and incidence has been increasing over time. A national web-based Notifiable Diseases Surveillance System (NDSS) has been in operation since 1997 to monitor incidence and trends and support case and outbreak management. We present the findings of an evaluation of the NDSS to ascertain the extent to which dengue fever surveillance objectives are being achieved.MethodologyWe extracted the NDSS data on all laboratory-confirmed dengue fever cases reported during 1 January 2010 to 31 December 2012 to assess and describe key system attributes based on the Centers for Disease Control and Prevention surveillance evaluation guidelines. The system’s structure and processes were delineated and operational staff interviewed using a semi-structured questionnaire. Crude and age-adjusted incidence rates were calculated and key demographic variables were summarised to describe reporting activity. Data completeness and validity were described across several variables.Conclusions/SignificanceThe NDSS for dengue fever surveillance is a robust, well maintained and acceptable system that supports the collection of complete and valid data needed to achieve the surveillance objectives. The simplicity of the system engenders compliance leading to timely and accurate reporting. Completeness of hospitalization information could be further improved to allow assessment of severity of illness. To minimize misclassification, an algorithm to accurately classify travel cases should be established.  相似文献   

14.
In earlier studies, we found more economical runners having a more compliant quadriceps femoris (QF) tendon at low force levels, and a higher contractile strength and stiffness at the triceps surae (TS). To better understand how these differences influence force generation economy and energy recovery, we simulated contractions using a Hill-type muscle model and the previously determined muscle properties as input parameters. For eight different activation levels, we simulated isovelocity concentric contractions preceded by an isovelocity stretch. The length changes and contraction velocities imposed to the muscle–tendon units (MTU) corresponded to those happening whilst running. The main results of the simulations were: (a) a more compliant tendon at low force levels (QF) led to an advantage in force-generation due to a decrease in shortening velocity of the CE, (b) a higher contractile strength and higher stiffness at the TS led to a disadvantage in force-generation at high activation levels and to an advantage at low activation levels. In addition at the high economy runners both MTUs showed an advantageous energy release during shortening, which at the QF was mainly due to a higher elongation of the SEE and at the TS mainly to the higher contractile strength. Especially at low activation levels both MTUs showed an advantageous force generation per activation and a higher energy release as compared to the low economy runners.  相似文献   

15.
16.
Trypanosome infections were sought in 46 non-human primates captured principally in Amazonian Brazil. Twenty-two (47.8%) were infected with four Trypanosoma species: T. cruzi, T. minasense, T. devei and T. rangeli. These preliminary results confirmed the high prevalence and diversity of natural infections with trypanosomes in primates from Brazilian Amazon and were the first formal record of simian infections with trypanosomes in the State of Acre. The presence of T. cruzi-like and T. rangeli-like parasites are recorded in four new hosts.  相似文献   

17.
Hunting regulations for grizzly bears (Ursus arctos) in much of Alaska since 1980 increasingly were designed to reduce bear abundance in the expectation such regulations would lead to increased harvests by hunters of moose (Alces alces) and caribou (Rangifer tarandus). Regulations were liberalized during 1980–2010 primarily in the area we termed the Liberal Grizzly Bear Hunting Area (hereafter Liberal Hunt Area) which encompassed 76.2% of Alaska. By 2010, these changes resulted in longer hunting seasons (100% of Liberal Hunt Area had seasons > 100 days, 99.7% > 200 days, and 67.8% > 300 days), more liberal bag limits (99.1% of the Liberal Hunt Area with a bag limit ≥ 1/yr and 10.1% with a bag limit ≥ 2/yr), and widespread waiver of resident tag fees (waived in 95.7% of the Liberal Hunt Area). During 1995–2010, there were 124 changes that made grizzly bear hunting regulations more liberal and two making them more conservative. The 4-year mean for grizzly bear kills by hunters increased 213% between 1976–1980 (387 grizzly bears) and 2005–2008 (823 grizzly bears). Since 2000, long-term research studies on grizzly populations in the Liberal Hunt Area have been terminated without replacement. Management of large predators by the State of Alaska is constrained by a 1994 state statute mandating “intensive management” in areas classified as important for human consumptive use of ungulates. Current grizzly bear management in the Liberal Hunt Area is inconsistent with the recommendations of the National Research Council's 1997 report on predator management in Alaska. Current attitudes, policies and absence of science-based management of grizzly bears in Alaska are increasingly similar to those that resulted in the near extirpation of grizzly bears south of Canada in the 19th and 20th centuries. If current trends continue, they increase risks to portions of the largest and most intact population of grizzly bears in North America. © 2011 The Wildlife Society.  相似文献   

18.
Char Ullman 《Ethnos》2015,80(2):223-247
ABSTRACT

Given the harsh environment for Mexican migrants in the US state of Arizona, migrants must think carefully about instantiating their identities in White public space through clothing, bodily movements, and language. This article explores the ways some unauthorized Mexican migrants in Arizona perform belonging to the USA by performing Chicano. Performing Chicano means passing as a US citizen, and migrants’ well-being can depend upon the recognition of those performances. Other unauthorized migrants perform the Supermexicana, to pass as Mexicans who are shopping in the USA, and need to hide the fact that they clandestinely live there. This article examines how some migrants perform a commitment to the USA in public while privately disavowing it, and how others perform a commitment to Mexico that they simply cannot have. This analysis argues that the experiences of unauthorized migrants in the USA can be productively seen through the lens of national performativity.  相似文献   

19.
This paper discusses the life and scientific work of José Vicente Barbosa du Bocage (1823–1907), a nineteenth-century Portuguese naturalist who carved a new place for zoological research in Portugal and built up a prestigious scientific career by securing appropriate physical and institutional spaces to the discipline. Although he was appointed professor of zoology at the Lisbon Polytechnic School, an institution mainly devoted to the preparatory training of military officers and engineers, he succeeded in creating the conditions that allowed him to develop consistent research in zoology at this institution. Taking advantage of the reconstruction and further improvement of the building of the Lisbon Polytechnic, following a violent fire in 1843, Bocage transferred a natural history museum formerly located at the Academy of Sciences of Lisbon to his institution, where he conquered a more prestigious place for zoology. Although successive governments were unwilling to meet Bocage’s ambitions for the Zoological Section of the newly created National Museum of Lisbon, the collaborators he found in different parts of the Portuguese continental territory and colonial empire supplied him the specimens he needed to make a career as a naturalist. Bocage ultimately became a renowned specialist in Southwestern African fauna thanks to José de Anchieta, his finest collaborator. Travels to foreign museums, and the establishment of links with the international community of zoologists, proved fundamental to build up Bocage’s national and international scientific reputation, as it will be exemplified by the discussion of his discovery of Hyalonema, a specimen with a controversial identity collected off the Portuguese coast.  相似文献   

20.

Background

The health transition theory argues that societal changes produce proportional changes in causes of disability and death. The aim of this study was to identify long-term changes in main causes of hospitalization in working-age population within a nation that has experienced considerable societal change.

Methodology

National trends in all-cause hospitalization and hospitalizations for the five main diagnostic categories were investigated in the data obtained from the Finnish Hospital Discharge Register. The seven-cohort sample covered the period from 1976 to 2010 and consisted of 3,769,356 randomly selected Finnish residents, each cohort representing 25% sample of population aged 18 to 64 years.

Principal Findings

Over the period of 35 years, the risk of hospitalization for cardiovascular diseases and respiratory diseases decreased. Hospitalization for musculoskeletal diseases increased whereas mental and behavioral hospitalizations slightly decreased. The risk of cancer hospitalization decreased marginally in men, whereas in women an upward trend was observed.

Conclusions/Significance

A considerable health transition related to hospitalizations and a shift in the utilization of health care services of working-age men and women took place in Finland between 1976 and 2010.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号