Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
Add more filters










Database
Language
Publication year range
1.
Ecol Evol ; 14(3): e11104, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38435010

ABSTRACT

Current environmental changes may increase temporal variability of life history traits of species thus affecting their long-term population growth rate and extinction risk. If there is a general relationship between environmental variances (EVs) and mean annual survival rates of species, that relationship could be used as a guideline for analyses of population growth and extinction risk for populations, where data on EVs are missing. For this purpose, we present a comprehensive compilation of 252 EV estimates from 89 species belonging to five vertebrate taxa (birds, mammals, reptiles, amphibians and fish) covering mean annual survival rates from 0.01 to 0.98. Since variances of survival rates are constrained by their means, particularly for low and high mean survival rates, we assessed whether any observed relationship persisted after applying two types of commonly used variance stabilizing transformations: relativized EVs (observed/mathematical maximum) and logit-scaled EVs. With raw EVs at the arithmetic scale, mean-variance relationships of annual survival rates were hump-shaped with small EVs at low and high mean survival rates and higher (and widely variable) EVs at intermediate mean survival rates. When mean annual survival rates were related to relativized EVs the hump-shaped pattern was less distinct than for raw EVs. When transforming EVs to logit scale the relationship between mean annual survival rates and EVs largely disappeared. The within-species juvenile-adult slopes were mainly positive at low (<0.5) and negative at high (>0.5) mean survival rates for raw and relativized variances while these patterns disappeared when EVs were logit transformed. Uncertainties in how to interpret the results of relativized and logit-scaled EVs, and the observed high variation in EV's for similar mean annual survival rates illustrates that extrapolations of observed EVs and tests of life history drivers of survival-EV relationships need to also acknowledge the large variation in these parameters.

2.
ChemSusChem ; 16(21): e202300333, 2023 Nov 08.
Article in English | MEDLINE | ID: mdl-37341155

ABSTRACT

In this bibliometric study, we analyze two of the six battery research subfields identified in the BATTERY 2030+ roadmap: Materials Acceleration Platform and Smart functionalities: Sensing. In addition, we analyze the entire research field related to BATTERY 2030+ as a whole. We (a) evaluate the European standing in the two subfields/the BATTERY 2030+ field in comparison to the rest of the world, and (b) identify strongholds of the two subfields/the BATTERY 2030+ field across Europe. For each subfield and the field as a whole, we used seed articles, i. e. articles listed in the BATTERY 2030+ roadmap or cited by such articles, in order to generate additional, similar articles located in an algorithmically obtained classification system. The output of the analysis is publication volumes, field normalized citation impact values with comparisons between country/country aggregates and between organizations, co-publishing networks between countries and organizations, and keyword co-occurrence networks.

3.
J Synchrotron Radiat ; 27(Pt 5): 1415-1429, 2020 Sep 01.
Article in English | MEDLINE | ID: mdl-32876619

ABSTRACT

BioMAX is the first macromolecular crystallography beamline at the MAX IV Laboratory 3 GeV storage ring, which is the first operational multi-bend achromat storage ring. Due to the low-emittance storage ring, BioMAX has a parallel, high-intensity X-ray beam, even when focused down to 20 µm × 5 µm using the bendable focusing mirrors. The beam is tunable in the energy range 5-25 keV using the in-vacuum undulator and the horizontally deflecting double-crystal monochromator. BioMAX is equipped with an MD3 diffractometer, an ISARA high-capacity sample changer and an EIGER 16M hybrid pixel detector. Data collection at BioMAX is controlled using the newly developed MXCuBE3 graphical user interface, and sample tracking is handled by ISPyB. The computing infrastructure includes data storage and processing both at MAX IV and the Lund University supercomputing center LUNARC. With state-of-the-art instrumentation, a high degree of automation, a user-friendly control system interface and remote operation, BioMAX provides an excellent facility for most macromolecular crystallography experiments. Serial crystallography using either a high-viscosity extruder injector or the MD3 as a fixed-target scanner is already implemented. The serial crystallography activities at MAX IV Laboratory will be further developed at the microfocus beamline MicroMAX, when it comes into operation in 2022. MicroMAX will have a 1 µm × 1 µm beam focus and a flux up to 1015 photons s-1 with main applications in serial crystallography, room-temperature structure determinations and time-resolved experiments.

4.
Sci Total Environ ; 650(Pt 1): 1547-1553, 2019 Feb 10.
Article in English | MEDLINE | ID: mdl-30308840

ABSTRACT

Population growth in passerine birds is largely driven by fecundity. If fecundity is affected, for instance by hatching failure, populations may decline. We noted high hatching failure of up to 27% per year in relict populations of the Northern wheatear (Oenanthe oenanthe) in The Netherlands, a strongly declining, migratory passerine in Europe. This hatching failure itself can cause population decline, irrespective of other adverse factors. Additionally, we investigated the cause of hatching failure. Unhatched eggs showed egg yolk infections or embryonic malformations, part of which is associated with the actions of dioxin-like compounds (DLCs). Indeed, DLCs appear to bioaccumulate in the local foodweb, where the soil contained only background concentrations, similar to those found at many other locations. DLC concentrations in Dutch eggs were six-fold higher than those in a reference population in Sweden, where egg failure was only 6%. However, Northern wheatears appear to be only moderately sensitive to the actions of DLCs, because of their specific Ah-receptor type which may moderate the receptor mediated effects of DLCs. This indicates that the concentrations of DLCs, although elevated, may not have caused the embryo malformations or the low hatching rates. We discuss whether other toxins may be important or imbalances in the nutrition and if inbreeding may play a larger role than expected.


Subject(s)
Environmental Monitoring , Environmental Pollutants/metabolism , Food Chain , Passeriformes/physiology , Songbirds/physiology , Animals , Carcinogens , Dioxins , Liver/drug effects , Netherlands , Receptors, Aryl Hydrocarbon , Sweden
5.
Am Nat ; 179(6): 706-20, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22617260

ABSTRACT

Demographic stochasticity is important in determining extinction risks of small populations, but it is largely unknown how its effect depends on the life histories of species. We modeled effects of demographic stochasticity on extinction risk in a broad range of generalized life histories, using matrix models and branching processes. Extinction risks of life histories varied greatly in their sensitivity to demographic stochasticity. Comparing life histories, extinction risk generally increased with increasing fecundity and decreased with higher ages of maturation. Effects of adult survival depended on age of maturation. At lower ages of maturation, extinction risk peaked at intermediate levels of adult survival, but it increased along with adult survival at higher ages of maturation. These differences were largely explained by differences in sensitivities of population growth to perturbations of life-history traits. Juvenile survival rate contributed most to total demographic variance in the majority of life histories. Our general results confirmed earlier findings, suggesting that empirical patterns can be explained by a relatively simple model. Thus, basic life-history information can be used to assign life-history-specific sensitivity to demographic stochasticity. This is of great value when assessing the vulnerability of small populations.


Subject(s)
Demography , Extinction, Biological , Models, Biological , Animals , Fertility , Risk , Sexual Maturation , Stochastic Processes
6.
PLoS One ; 3(8): e3006, 2008 Aug 20.
Article in English | MEDLINE | ID: mdl-18714351

ABSTRACT

BACKGROUND: To assess population persistence of species living in heterogeneous landscapes, the effects of habitat on reproduction and survival have to be investigated. METHODOLOGY/PRINCIPAL FINDINGS: We used a matrix population model to estimate habitat-specific population growth rates for a population of northern wheatears Oenanthe oenanthe breeding in farmland consisting of a mosaic of distinct habitat (land use) types. Based on extensive long-term data on reproduction and survival, habitats characterised by tall field layers (spring- and autumn-sown crop fields, ungrazed grasslands) displayed negative stochastic population growth rates (log lambda(s): -0.332, -0.429, -0.168, respectively), that were markedly lower than growth rates of habitats characterised by permanently short field layers (pastures grazed by cattle or horses, and farmyards, log lambda(s): -0.056, +0.081, -0.059). Although habitats differed with respect to reproductive performance, differences in habitat-specific population growth were largely due to differences in adult and first-year survival rates, as shown by a life table response experiment (LTRE). CONCLUSIONS/SIGNIFICANCE: Our results show that estimation of survival rates is important for realistic assessments of habitat quality. Results also indicate that grazed grasslands and farmyards may act as source habitats, whereas crop fields and ungrazed grasslands with tall field layers may act as sink habitats. We suggest that the strong decline of northern wheatears in Swedish farmland may be linked to the corresponding observed loss of high quality breeding habitat, i.e. grazed semi-natural grasslands.


Subject(s)
Ecosystem , Passeriformes/physiology , Population Growth , Animals , Demography , Kinetics , Life Tables , Territoriality
SELECTION OF CITATIONS
SEARCH DETAIL
...