Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 11 de 11
Filter
Add more filters










Publication year range
1.
Sci Rep ; 9(1): 8573, 2019 06 12.
Article in English | MEDLINE | ID: mdl-31189927

ABSTRACT

The increasing trend of large carnivore attacks on humans not only raises human safety concerns but may also undermine large carnivore conservation efforts. Although rare, attacks by brown bears Ursus arctos are also on the rise and, although several studies have addressed this issue at local scales, information is lacking on a worldwide scale. Here, we investigated brown bear attacks (n = 664) on humans between 2000 and 2015 across most of the range inhabited by the species: North America (n = 183), Europe (n = 291), and East (n = 190). When the attacks occurred, half of the people were engaged in leisure activities and the main scenario was an encounter with a female with cubs. Attacks have increased significantly over time and were more frequent at high bear and low human population densities. There was no significant difference in the number of attacks between continents or between countries with different hunting practices. Understanding global patterns of bear attacks can help reduce dangerous encounters and, consequently, is crucial for informing wildlife managers and the public about appropriate measures to reduce this kind of conflicts in bear country.


Subject(s)
Animals, Wild/physiology , Conservation of Natural Resources , Ursidae/physiology , Animals , Female , Humans , Male
2.
Front Zool ; 15: 41, 2018.
Article in English | MEDLINE | ID: mdl-30410564

ABSTRACT

BACKGROUND: For brown bears (Ursus arctos), hibernation is a critical part of the annual life cycle because energy savings during hibernation can be crucial for overwintering, and females give birth to cubs at that time. For hibernation to be a useful strategy, timing is critical. However, environmental conditions vary greatly, which might have a negative effect on the functionality of the evolved biological time-keeping. Here, we used a long-term dataset (69 years) on brown bear denning phenology recorded in 12 Russian protected areas and quantified the phenological responses to variation in temperature and snow depth. Previous studies analyzing the relationship between climate and denning behavior did not consider that the brown bear response to variation in climatic factors might vary through a period preceding den entry and exit. We hypothesized that there is a seasonal sensitivity pattern of bear denning phenology in response to variation in climatic conditions, such that the effect of climatic variability will be pronounced only when it occurs close to den exit and entry dates. RESULTS: We found that brown bears are most sensitive to climatic variations around the observed first den exit and last entry dates, such that an increase/decrease in temperature in the periods closer to the first den exit and last entry dates have a greater influence on the denning dates than in other periods. CONCLUSIONS: Our study shows that climatic factors are modulating brown bear hibernation phenology and provide a further structuring of this modulation. The sensitivity of brown bears to changes in climatic factors during hibernation might affect their ability to cope with global climate change. Therefore, understanding these processes will be essential for informed management of biodiversity in a changing world.

3.
Fiziol Cheloveka ; 37(1): 105-17, 2011.
Article in Russian | MEDLINE | ID: mdl-21469360

ABSTRACT

On the basis of longitudinal studies in children of older preschool and early school-age boys and girls with low, medium and high habitual physical activity (NAPA, SPDA, VPDA) identified the basic characteristics of the cardiovascular system, physical capacity and the degree of tension of regulatory mechanisms at rest and during functional loading. Analysis of the statistical distribution of the trait given chi2 and lambda criteria and average data of various functional indicators in the total sample identified a fairly wide area and the divergent levels of physiological individuality in a healthy population and the desirability of allocating the three typological groups--functional types (FT-1 - NAPA, the FT-2 - SPDA, FT-3 - VPDA). Model parameters are allocated first and second order for each CFT, as well as performance tests of the third order, describing the current functional status. Determination of the physiological features of the FT-1 FT-2 FT-3 with the establishment of their functional reserves and adaptive capacity makes it possible to identify the different strategies of interaction with the environment, evaluate their advantages and disadvantages and a more grounded approach to the problem of optimization of physical condition and prenosological diagnosis.


Subject(s)
Child Development/physiology , Models, Biological , Motor Activity/physiology , Rest/physiology , Child , Child, Preschool , Female , Humans , Male
4.
Fiziol Cheloveka ; 37(6): 111-24, 2011.
Article in Russian | MEDLINE | ID: mdl-22332436

ABSTRACT

Analysis of the statistical distribution of feature based chi2 and lambda criteria and average data somatometric, functional and psycho-physiological indices in the total sample of individuals with low, medium and high habitual physical activity (LHPA, M H PA and HHP A) at different stages of ontogenesis (the older preschool and early school children, boys and girls) has identified a fairly wide area of different quality and physiological individuality in a healthy population and the feasibility of allocating the three typological groups--functional constitution types (FTC-1 - LHPA, FTC-2 - MHPA, FTC-3 - HHPA). Set model parameters of the first and second order for each FTC, as well as performance tests of the third order, describing the current functional state. For the full specifications of the constitutional membership (synthetic constitution) of individuals with low, medium and high-held PDA integral assessment of their properties by using the principles polythetic (multidimensional) classification. Obtained by means of multivariate statistical methods results confirmed the postulate of the concept of typological variability of physiological individuality real different quality of healthy human population on the morphofunctional and psycho-physiological grounds and conducted a comprehensive physiological and statistical analysis of results allowed us to scientifically justify the selection of three functional types of constitution (PTC-1, FTC-2, FTC-3), corresponding to three types of synthetic constitutive (K 0-1, K 00, K 01). The data obtained show that the system (constitutional) approach to the evaluation of individual-typological characteristics of the organism confirms the high information private constitution(PTC-1, FTC-2, FTC-3) in human biological organization, and the selected feature set can adequately differentiate the synthetic constitutional types in a formal basis.


Subject(s)
Body Constitution/physiology , Individuality , Motor Activity/physiology , Adolescent , Attention/physiology , Body Weights and Measures , Child , Cognition/physiology , Female , Humans , Male , Young Adult
8.
Klin Lab Diagn ; (11): 44, 2003 Nov.
Article in Russian | MEDLINE | ID: mdl-14708372

ABSTRACT

The purpose of the case study was to evaluate the diagnostic efficiency of radioimmunoassay (RIA) and of immune-enzyme assay (IEA) in indicating the HBsAg in the blood of children with viral hepatitis. The study was based on a simultaneous indication of HBsAg by RIA and IEA in 98 samples of blood serum (plasma). It was shown that both assays are practically univocal in as far as the HBsAg indication within the mentioned circumstances is concerned.


Subject(s)
Hepatitis B Antigens/blood , Hepatitis, Viral, Human/diagnosis , Adolescent , Child , Child, Preschool , Female , Hepatitis A/diagnosis , Hepatitis A Antibodies/blood , Hepatitis B/diagnosis , Humans , Immunoenzyme Techniques , Male , Radioimmunoassay , Reference Values , Reproducibility of Results
10.
Prikl Biokhim Mikrobiol ; 11(4): 539-45, 1975.
Article in Russian | MEDLINE | ID: mdl-1737

ABSTRACT

The effect of low pH values on the activity and stability of the quaternary structure of asparaginase from Escherichia coli was investigated at early stages of purification of the enzyme. Acidification of the E. coli extract was most effective before the biomass separation. This procedure helped to separate biomass together with coagulated ballast proteins and not to reduce the activity. Upon storage of the acidified solution at 5 degrees C reversible dissociation of the tetrametric structure into dimers and monomers occurred. Stability of L-asparaginase in the storage of acetone powders and during extraction was studied. It is suggested that asparaginase in bacterial cells in unlikely to have the quaternary structure which normally occurs in the solution at neutral pH.


Subject(s)
Asparaginase/metabolism , Escherichia coli/enzymology , Binding Sites , Cold Temperature , Drug Stability , Hydrogen-Ion Concentration , Kinetics , Macromolecular Substances , Protein Binding , Protein Conformation
SELECTION OF CITATIONS
SEARCH DETAIL
...