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Male incubation in barn swallows: the influence of nest temperature and sexual selection

Male Barn Swallows (Hirundo rustica) help their mates to incubate in North America but not in Europe. In this study, conducted at four colonies in southeastern Canada, males contributed an average of 9% of the total amount of incubation during daylight hours. The total percent of time that eggs were incubated (nest attentiveness) by both sexes declined through the day, largely due to a response to

Parental age and reproduction in the marsh tit

In the Marsh Tit Parus palustris, breeding performance improved with the age of both the male and the female parent-older birds produced larger clutches earlier in the season. The effect of male age, however, was mainly due to a positive association with the age of the female. When the effect of laying date was accounted for, there was no additional effect of female age on clutch-size. However, pa

Interclutch variation in egg size among starlings (Sturnus vulgaris) reflects female condition

Starlings show considerable variation in egg mass among clutches. Mean clutch egg mass was highly repeatable for females, but few characteristics of females were found to relate to egg mass. Egg mass related weakly to female age, but female age only explained a small part of the variation. Hatchling mass was strongly correlated with egg mass, but body mass at 14 d of age was unrelated to egg mass.

Heritability of tarsus length in cross-fostered European Starling broods

A cross-fostering experiment demonstrated that tarsus length of European starlings (Sturnus vulgaris) was heritable. The tarsus length of the foster-parent had no effect. A full-sib resemblance analysis showed that sibs were much more similar in tarsus length than explained by heritability alone. This was partly due to an effect of female mating status on offspring tarsus length. When nestling gro

A comparison between physical and virtual experiments of convective heat transfer between head and bicycle helmet

Thermal performance of five bicycle helmets was evaluated with a thermal manikin head with six zones. Evaluation was made with physical and virtual experimental methods. Ambient temperature maintained at 24 °C and surface temperature of the thermal manikin head was set to 34 °C. Experiments were performed for air velocities of 1.6 m/s and 6 m/s. Heat transfer (W) of four thermal zones was recorded

Compact acceleration of energetic neutral atoms using high intensity laser-solid interaction

Recent advances in high-intensity laser-produced plasmas have demonstrated their potential as compact charge particle accelerators. Unlike conventional accelerators, transient quasi-static charge separation acceleration fields in laser produced plasmas are highly localized and orders of magnitude larger. Manipulating these ion accelerators, to convert the fast ions to neutral atoms with little cha

Reduced tillage stimulated symbiotic fungi and microbial saprotrophs, but did not lead to a shift in the saprotrophic microorganism community structure

The need for sustainable agricultural systems, which for example enhance soil organic carbon (SOC) content, has increased the interest for management with reduced tillage. In this study we used a Swedish long-term (20 yrs.) systems experiment, including reduced tillage (harrowing 10 cm) and plowing (moldboard plow 0–20 cm) combined with three levels of nitrogen (N) fertilization. With this setup w

The reversibility of the snuff-induced lesion : an experimental study in the rat

Snuff lesions were induced in 30 rats. Ten of the snuff-exposed rats were killed immediately after 13 months snuff exposure, as were the 10 control animals. Ten rats were killed 1 month and 10 rats 4 months after the snuff administration had ceased. The rats exposed to snuff for 13 months exhibited hyperplastic, hyperorthokeratotic epithelium with focal mild atypia, focal ulcerations and marked su

Amputations due to lower-limb ischemia. Analysis of a 3-year series

Lower-limb amputation was performed on 261 patients from a catchment population of 232,500 in 1984-1986, and 253 of the amputees were retrospectively followed up. In 241 cases amputation was performed because of threatening or manifest gangrene, 95 of them without preceding consultation with vascular surgeons. In 19 cases amputation followed thromboembolectomy. Of the 127 patients seen by vascular

An integrated approach to design site specific distributed electrical hubs combining optimization, multi-criterion assessment and decision making

An integrated approach is presented in this study to design electrical hubs combining optimization, multi-criterion assessment and decision making. Levelized Energy Cost (LEC), Initial Capital Cost (ICC), Grid Integration Level (GI), Levelized CO2 emission (LCO2), utilization of renewable energy, flexibility of the system, loss of load probability (LOLP) are considered as criteria used to assess t

The Plasmodium serine-type SERA proteases display distinct expression patterns and non-essential in vivo roles during life cycle progression of the malaria parasite

Parasite proteases play key roles in several fundamental steps of the Plasmodium life cycle, including haemoglobin degradation, host cell invasion and parasite egress. Plasmodium exit from infected host cells appears to be mediated by a class of papain-like cysteine proteases called 'serine repeat antigens' (SERAs). A SERA subfamily, represented by Plasmodium falciparum SERA5, contains an atypical

Expression and processing of Plasmodium berghei SERA3 during liver stages

Cysteine proteases mediate liberation of Plasmodium berghei merozoites from infected hepatocytes. In an attempt to identify the responsible parasite proteases, we screened the genome of P. berghei for cysteine protease-encoding genes. RT-PCR analyses revealed that transcription of four out of five P. berghei serine repeat antigen (PbSERA) genes was strongly upregulated in late liver stages briefly

The liver stage of Plasmodium berghei inhibits host cell apoptosis

Plasmodium berghei is the causative agent of rodent malaria and is widely used as a model system to study the liver stage of Plasmodium parasites. The entry of P. berghei sporozoites into hepatocytes has extensively been studied, but little is known about parasite-host interaction during later developmental stages of the intracellular parasite. Growth of the parasite far beyond the normal size of