18 research outputs found
Foraging behaviour and fuel accumulation of capital breeders during spring migration as derived from a combination of satellite- and ground-based observations
The work was supported by Aarhus Univ., Denmark, the Norwegian Research Council (project MIGRAPOP, granted to I. Tombre) and the Schure-Beijerinck-Popping Fund (granted to BAN).The migration strategy of many capital breeders is to garner body stores along the flyway at distinct stopover sites. The rate at which they can fuel is likely to be strongly influenced by a range of factors, such as physiology, food availability, time available for foraging and perceived predation. We analysed the foraging behaviour and fuel accumulation of pink-footed geese, an Arctic capital breeder, at their mid-flyway spring stopover site and evaluated to what extent their behaviour and fuelling were related to physiological and external factors and how it differed from other stopovers along the flyway. We found that fuel accumulation rates of geese at the mid-flyway site were limited by habitat availability rather than by digestive constraints. However, as the time available for foraging increased over the stopover season, geese were able to keep constant fuelling rate. Putting this in perspective, geese increased their daily net energy intake along the flyway corresponding to the increase in time available for foraging. The net energy intake per hour of foraging remained the same. Geese showed differences in their reaction to predators/disturbance between the sites, taking higher risks particularly at the final stopover site. Hence, perceived predation along the flyway may force birds to postpone the final fuel accumulation to the last stopover along the flyway. Flexibility in behaviour appears to be an important trait to ensure fitness in this capital breeder. Our findings are based on a new, improved method for estimating fuel accumulation of animals foraging in heterogeneous landscapes based on data obtained from satellite telemetry and habitat specific intake rates.Publisher PDFPeer reviewe
AgentSeal : agent-based model describing movement of marine central-place foragers
Acknowledgement This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 746602. GA and SB have been partly funded by Gemini Wind park and the NWO (project ALWPP.2017.003). We would like to thank J. Grecian, D. Thomson, M. Fedak, M. Carter, D. Russell, A. Hall, J. Ransijn, H. Vance and M. Civil for help in model design.Peer reviewedPublisher PD
RENAL TRANSPLANTATION IN PATIENTS WITH LUPUS NEPHRITIS
Zahvaćanje bubrega teška je komplikacija sistemskog eritemskog lupusa, praćena visokim pobolijevanjem i smrtnošću. Do razvoja lupusnog nefritisa dolazi u do 60% oboljelih, a unatoč primjeni novih i potentnijih terapijskih protokola u 5 do 22% ove specifične populacije razvije se završni stadij kronične bubrežne bolesti unutar 15 godina od postavljanja dijagnoze. Kako je SLE ponajprije vezan uz mlađu životnu dob, izuzetno je važno odabrati optimalan modalitet nadomještanja bubrežne funkcije. Brojne su studije provedene ne bi li se odgovorilo na kontroverzna pitanja vezana uz ovu specifičnu populaciju. Veća sklonost infekcijama, rizik od povratka osnovne bolesti u presadak, nedefinirani kriteriji praćenja aktivnosti bolesti nakon transplantacije te veća učestalost epizoda odbacivanja i trombotskih događaja rizični su čimbenici zbog kojih se ovoj skupini dugo vremena onemogućavalo liječenje transplantacijom. Rezultati studija nedvojbeno pokazuju da je dugoročno preživljenje podjednako u liječenih hemodijalizom i peritonealnom dijalizom, no transplantacija bubrega nametnula se kao mnogo bolja metoda koja omogućava dulje preživljenje i veću kvalitetu života, umanjujući istodobno aktivnost samog SLE-a. Iako postoje brojna neistražena i neodgovorena pitanja vezana uz zbrinjavanje ove imunosno vrlo osjetljive i zahtjevne skupine bolesnika, pažljiva skrb prije i nakon transplantacije te uska suradnja nefrologa i imunologa omogućavaju dobar ishod uz znatno povećanje kvalitete života.Lupus nephritis (LN) is a severe complication of systemic lupus erythematosus (SLE), associated with high morbidity and mortality. Up to 60% of SLE patients develop LN, and despite novel and potent therapeutic regimens, 5 to 22% develop end-stage renal disease within 15 years of diagnosis. While LN primarily affects younger individuals, it is important to choose optimal method of renal replacement therapy for those who develop end-stage renal disease. Numerous studies were carried out trying to solve problems of treatment of patients with LN. Increased risk of infections, disease recurrence in renal allograft, undefined criteria for follow-up of disease activity after transplantation, as well as higher incidence of rejection episodes and thrombotic events are well known risks which have postponed and restricted access to transplantation for patients with LN for long-time. However, numerous studies have demonstrated similar long-term survival in patients treated with haemodialysis or peritoneal dialysis, with clear superiority of renal transplantation regarding the prolonged survival and better quality of life for SLE patients. Many questions are still waiting for answers. Close cooperation between nephrologists and immunologists provides the best treatment for SLE patients with end-stage renal disease
Tracing potential soil contamination in the historical Solvay soda ash plant area, Jaworzno, Southern Poland
This study of soil conditions was carried out on 30 meadow soil (podzol) samples from the vicinity of the soda ash heap in Jaworzno, supplemented by analyses of 18 samples of waste deposited on the heap. In all samples, the total content of macroelements (Ca and Na) and heavy metals (Cd, Cr, Ni, Pb and Zn) as well as pH were analysed. The element concentrations were measured using inductively coupled plasma optical emission spectrometry (ICP-OES). The materials examined were neutral to ultra-alkaline. Total accumulations (mg kg(−1)) of chemical elements in the soil vary from 130.24 to 14076.67 for Ca, 41.40–926.23 for Na, 0.03–3.34 for Cd, 0.94–103.62 for Cr, 0.94–35.89 for Ni, 3.51–76.47 for Pb and 12.05–279.13 for Zn, whereas quantities of the same elements in the waste samples vary from 171705.13 to 360487.94 for Ca, 517.64–3152.82 for Na, 0.2–9.89 for Cd, 1.16–20.40 for Cr, 1.08–9.79 for Ni, 0.1–146.05 for Pb and 10.26–552.35 for Zn. The vertical distribution of the metals was determined in each soil profile. Despite enrichment of heavy metals in the uppermost horizon on the top of the heap, the results lead to the conclusion that the relation of historical production of soda ash in Jaworzno to current contamination of the local soil environment is insignificant
Accumulation of heavy metals and antioxidant responses in Pinus sylvestris L. needles in polluted and non-polluted sites
Zastosowanie współczynnika podziału do oceny ruchlowiści metali ciężkich w strefie oddziaływania huty cynku w miasteczku śląskim (Polska)
The present paper outlines some approaches, which were suggested for assessing heavy metals (Cu, Zn, Pb and Cd) mobility in soils contaminated by a zinc smelter activity. The concept was based on the assumption that partition coefficients, as ratios of total (assayed by aqua regia) metal contents to exchangeable (extracted by 1 mol CH3COONH4 dm–3 , pH 7.0) or to bioavailable (extracted by 0.1 mol NaNO3 dm–3) metal contents, will be more predictive in assessing metals mobility as compared with single extractions. The calculated partition coefficients for exchangeable and bioavailable metal forms were respectively termed Kd-Ex and Kd-Bio, which in turn were intended to represent the statico-dynamic nature of heavy metal mobility. It was found that metal mobility followed the sequence Cd > Zn > Pb > Cu, which implies that Cd and Zn will evoke more threat due to greater susceptibility for mobility. Regressions for the pairs logKd versus pH were applied in order to exhibit the proton generating capacity of each metal. The average calculated proton coefficient in the case of exchangeable metal forms amounted to 0.16 mole of protons released for each mole of Cu, Zn and Pb. In contrast, the proton coefficient for Cd was about 81 % greater. The estimation made on the basis of bioavailable metal forms showed, that Cd and Zn retention by soils generated, respectively 77 and 131 % more protons as compared to Pb. In terms of environmental concern, it may be formulated, that the higher the proton generating capacity, the highest the metal mobility, and thus the weakest partition to the solid phase.Praca przedstawia zagadnienia związane z oceną ruchliwości metali ciężkich (Cu, Zn, Pb, Cd) w glebach zanieczyszczonych w wyniku działalności huty cynku. Koncepcja opierała się na założeniu, że współczynniki podziału jako stosunki całkowitej zawartości metali (oznaczonej w wodzie królewskiej) do zawartości wymiennych (ekstrahowanych przez 1 mol CH3COONH4 dm-3 , pH 7.0) lub do zawartości biodostępnych (ekstrahowanych przez 0.10 mol NaNO3 dm-3 ) metali są bardziej przydatne do prognozowania ruchliwości metali ciężkich niż w przypadku pojedynczych ekstrakcji. Obliczone współczynniki podziału przyjęto odpowiednio jako Kd-Ex i Kd-Bio, które z kolej miały odzwierciedlić statyczno-dynamiczny charakter ruchliwości metali ciężkich. Uzyskane wyniki przedstawiają szereg Cd > Zn > Pb > Cu, z którego wynika, że Cd i Zn stanowią większe zagrożenie z uwagi na większą ich ruchliwość w glebie. Zależności między log Kd a pH wykorzystano w celu obliczenia zdolności każdego metalu do generowania jonów wodorowych. Średnie wartości obliczone dla wymiennych form metali wynosiły 0.16 mola protonów uwolnionych na każdy mol Cu, Zn i Pb w odróżnieniu od Cd, dla którego wartość ta była o 81 % większa. Oszacowanie dokonane na podstawie zawartości biodostępnych form metali ujawniło, że zatrzymywanie Cd i Zn przez gleby spowodowało generowanie odpowiednio o 77 i 131 % więcej protonów w porównaniu z Pb. Biorąc pod uwagę zagrożenie przyrodnicze, należy przyjąć, że im większa zdolność do generowania protonów, tym większą ruchliwość wykazuje dany metal i tym samym słabsze jest jego zatrzymywanie przez fazę stałą gleby
Genetic resources of the oldest trees of Pinus sylvestris L. from the last natural forest in Europe
Foraging behaviour and fuel accumulation of capital breeders during spring migration as derived from a combination of satellite- and ground-based observations
The migration strategy of many capital breeders is to garner body stores along the flyway at distinct stopover sites. The rate at which they can fuel is likely to be strongly influenced by a range of factors, such as physiology, food availability, time available for foraging and perceived predation. We analysed the foraging behaviour and fuel accumulation of pink-footed geese, an Arctic capital breeder, at their mid-flyway spring stopover site and evaluated to what extent their behaviour and fuelling were related to physiological and external factors and how it differed from other stopovers along the flyway. We found that fuel accumulation rates of geese at the mid-flyway site were limited by habitat availability rather than by digestive constraints. However, as the time available for foraging increased over the stopover season, geese were able to keep constant fuelling rate. Putting this in perspective, geese increased their daily net energy intake along the flyway corresponding to the increase in time available for foraging. The net energy intake per hour of foraging remained the same. Geese showed differences in their reaction to predators/disturbance between the sites, taking higher risks particularly at the final stopover site. Hence, perceived predation along the flyway may force birds to postpone the final fuel accumulation to the last stopover along the flyway. Flexibility in behaviour appears to be an important trait to ensure fitness in this capital breeder. Our findings are based on a new, improved method for estimating fuel accumulation of animals foraging in heterogeneous landscapes based on data obtained from satellite telemetry and habitat specific intake rates.</p
Genetic profile of the oldest Picea abies (L.) Karst. trees in the Białowieza Primeval Forest
The aim of this study was to: 1) describe the genetic structure of the population of old Picea abies trees in the Białowieża Primeval Forest and 2) design the genetic database for every examined tree in scope of 26 isoenzymatic loci containing: the genotype pattern, the number of stated alleles and the level of individual heterozygosity. We found that 101 out of 117 trees are characterized by a unique genotype pattern and 20 ones are completely homozygous individuals. The oldest Norway spruces in the Białowieża Primeval Forest are characterized by rather low level of genetic variation and their homozygous genotypes that are well adapted to their environment let them live to a ripe old age