Search results for "annual"
showing 10 items of 168 documents
Scavengers on the move: behavioural changes in foraging search patterns during the annual cycle
2013
Background: Optimal foraging theory predicts that animals will tend to maximize foraging success by optimizing search strategies. However, how organisms detect sparsely distributed food resources remains an open question. When targets are sparse and unpredictably distributed, a Lévy strategy should maximize foraging success. By contrast, when resources are abundant and regularly distributed, simple Brownian random movement should be sufficient. Although very different groups of organisms exhibit Lévy motion, the shift from a Lévy to a Brownian search strategy has been suggested to depend on internal and external factors such as sex, prey density, or environmental context. However, animal re…
Incidence and time trends of soft tissue sarcomas in German children 1985-2004 - a report from the population-based German Childhood Cancer Registry.
2008
Abstract The incidence of soft tissue sarcoma (STS) in Europe is increasing, but it is unclear whether this increase can also be seen in Germany. We analysed the heterogeneous group of STS recorded to the German Childhood Cancer Registry (GCCR) between 1985 and 2004 with respect to incidence data. Age-specific, age-standardised and cumulative incidence rates were calculated. Additionally, the average annual percent change (AAPC), derived from a Poisson regression model, was estimated, using time in years as the explanatory, continuous variable. Two thousand sixty-one children were diagnosed at a median age of 72 months. Most common are rhabdomyosarcomas (RMS) (n = 1202) and fibrosarcomas (n…
Air Pollution and Recent Symptoms of Asthma, Allergic Rhinitis, and Atopic Eczema in Schoolchildren Aged Between 6 and 7 Years
2008
Abstract Objective The objective of the study was to analyze the relationship between air pollutants and the prevalence of recent symptoms of asthma, allergic rhinitis, and atopic eczema in schoolchildren aged between 6 and 7 years. Patients and Methods The prevalence of recent (previous 12 months) symptoms of allergic diseases was obtained by means of the questionnaire of the International Study of Asthma and Allergies in Childhood (ISAAC), Spain, with the participation of 7 centers (Asturias, Barcelona, Bilbao, Cartagena, La Coruna, Madrid, and Valencia) and 20 455 schoolchildren aged between 6 and 7 years, from 2002 to 2003. The pollutant detection systems of the aforementioned centers p…
Simultaneous age‐dependent and age‐independent sexual selection in the lekking black grouse(Lyrurus tetrix)
2014
Individuals' reproductive success is often strongly associated with their age, with typical patterns of early‐life reproductive improvement and late‐life senescence. These age‐related patterns are due to the inherent trade‐offs between life‐history traits competing for a limited amount of resources available to the organisms. In males, such trade‐offs are exacerbated by the resource requirements associated with the expression of costly sexual traits, leading to dynamic changes in trait expression throughout their life span. Due to the age dependency of male phenotypes, the relationship between the expression of male traits and mating success can also vary with male age. Hence, using longitu…
Incidence of type 1 diabetes among Polish children ages 0-14 years from 1989-2012.
2014
Aims The incidence of pediatric type 1 diabetes mellitus (T1DM) in Poland is intermediate relative to the rest of the world. T1DM prevalence in the region of Silesia approximates national estimates for all of Poland. This epidemiologic study aimed to analyze the changes in incidence rates of T1DM among children ages 0–14 years from 1989 to 2012 in this region. Methods Data collection methods for the registry followed EURODIAB criteria. To estimate overall population size, data from the Central and regional Statistical Office in Katowice were used. T1DM incidence rates/100,000 children ages 0–14 years/annum and their 95 % CI were calculated for all children and in age subgroups (0–4, 5–9, 10…
Last Interglacial Hydroclimate Seasonality Reconstructed From Tropical Atlantic Corals
2018
The seasonality of hydroclimate during past periods of warmer than modern global temperatures is a critical component for understanding future climate change scenarios. Although only partially analogous to these scenarios, the last interglacial (LIG, Marine Isotope Stage 5e, ~127–117 ka) is a popular test bed. We present coral δ18O monthly resolved records from multiple Bonaire (southern Caribbean) fossil corals (Diploria strigosa) that date to between 130 and 118 ka. These records represent up to 37 years and cover a total of 105 years, offering insights into the seasonality and characteristics of LIG tropical Atlantic hydroclimate. Our coral δ18O records and available coral Sr/Ca-sea surf…
A Simple Analytical Model for Remote Assessment of the Dynamics of Biomass Accumulation
2011
Efficient means for assessment of the dynamics and the state of the stocks of renewable assets such as wood biomass are important for sustainable supplies satisfying current needs. So far attention has been paid mainly to the economic aspects of forest management while ecological problems are rising with the expected transfer from fossil to renewable resources supplies of which from forest being essential for traditional consumers of wood and for emerging biorefineries. Production of biomass is more reliant on assets other than money the land (territory) available and suitable for the purpose being the first in the number. Studies of the ecological impacts (the “footprint”) of sustainable u…
Variation in pheno-morphological and agronomic traits among burr medic (Medicago polymorpha L.) populations collected in Sicily, Italy
2010
The present study assessed the diversity of pheno-morphological and agronomic traits among 31 natural populations of burr medic (Medicago polymorpha L.) from different environments throughout Sicily, and analysed the patterns of phenotypic diversity in relation to the environmental parameters of each collection site. Three commercial cultivars (Cavalier, Santiago, and Anglona) were also included in the study as check cultivars. Two field experiments were performed in 2005–06 in a hilly area of the Sicilian inland. Principal components analysis (PCA) was performed on the sites using geographic, climatic, and pedological data to assess the differences in types of collection sites. PCA was al…
Classification of Extreme Rainfall for a Mediterranean Region by Means of Atmospheric Circulation Patterns and Reanalysis Data
2020
AbstractThe atmospheric circulation can be recognized as one of the causes of severe rainfall events occurrence. Such events, especially when are characterized by short durations and high intensities, result in flood events in the Mediterranean area. It is very important to understand how these heavy rainfall events, which can be usually identified with convective rainfall, are related to the different types of atmospheric circulation. In order to do this, some weather circulation patterns (WPs), which have been derived for the Europe, have been first connected with the rainfall annual maxima (AMAX) recorded over the Sicily. The analyses allowed to identify those WPs that are more likely to…
Weakening of annual temperature cycle over the Tibetan Plateau since the 1870s
2017
The annual cycle of extra-tropical surface air temperature is an important component of the Earth's climate system. Over the past decades, a reduced amplitude of this mode has been observed in some regions. Although attributed to anthropogenic forcing, it remains unclear when dampening of the annual cycle started. Here we use a residual series of tree-ring width and maximum latewood density from the Tibetan Plateau >4,000 m asl to reconstruct changes in temperature seasonality over the past three centuries. The new proxy evidence suggests that the onset of a decrease in summer-to-winter temperature difference over the Tibetan Plateau occurred in the 1870s. Our results imply that the influen…