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51.
52.
In the majority of socially monogamous bird species, females have offspring sired by males other than their social mate as the result of extra-pair copulations. While it is widely recognised that there is considerable variation in the frequency of extra-pair paternity between species, between populations of a species and between individuals of a population, determinants of this variation are surprisingly difficult to establish. With respect to individual variation within a population, it is an important step to test for male and female correlates of cuckoldry to better understand the patterns as well as the adaptive significance of extra-pair mating behaviour. Here, we analysed patterns of extra-pair paternity in relation to male age, female age and their interaction in the great tit Parus major, a socially monogamous passerine with a moderate frequency of extra-pair paternity. Based on a large sample of 316 genotyped first broods from five successive years, we failed to demonstrate interaction effects of male and female age on both the proportion of extra-pair offspring and the likelihood that at least one extra-pair offspring is present within a brood. However, both the proportion of extra-pair offspring and the likelihood of paternity loss were higher for yearling as compared to older males, while this was not the case for yearling vs. older females. Furthermore, the proportion of extra-pair offspring within a brood decreased with increasing age of the attending male in within-individual analyses. We found a comparable effect also for attending females in within-individual analyses, but only when excluding two individuals with 100% extra-pair paternity. A female (extra-pair) mating preference for older males and/or a limited ability of yearling males to prevent cuckoldry in their broods could explain these age-related patterns of paternity loss. Effect sizes, however, were not particularly large and substantial residual variation within age categories suggests the importance of further yet unidentified determinants of variation in paternity loss in the study population. 相似文献
53.
Letícia Muraro Wildner Maria Luiza Bazzo Susie Coutinho Liedke Christiane Louren?o Nogueira Gabriela Segat Simone Gon?alves Senna Aline Daiane Schlindwein Jaquelline Germano de Oliveira Darcita B Rovaris Claudio A Bonjardim Erna G Kroon Paulo CP Ferreira 《Memórias do Instituto Oswaldo Cruz》2014,109(3):356-361
The identification of mycobacteria is essential because tuberculosis (TB) and
mycobacteriosis are clinically indistinguishable and require different therapeutic
regimens. The traditional phenotypic method is time consuming and may last up to 60
days. Indeed, rapid, affordable, specific and easy-to-perform identification methods
are needed. We have previously described a polymerase chain reaction-based method
called a mycobacteria mobility shift assay (MMSA) that was designed for
Mycobacterium tuberculosis complex (MTC) and nontuberculous mycobacteria
(NTM) species identification. The aim of this study was to assess the MMSA for the
identification of MTC and NTM clinical isolates and to compare its performance with
that of the PRA-hsp65 method. A total of 204 clinical isolates (102
NTM and 102 MTC) were identified by the MMSA and PRA-hsp65. For
isolates for which these methods gave discordant results, definitive species
identification was obtained by sequencing fragments of the 16S rRNA and
hsp65 genes. Both methods correctly identified all MTC isolates. Among
the NTM isolates, the MMSA alone assigned 94 (92.2%) to a complex or species, whereas
the PRA-hsp65 method assigned 100% to a species. A 91.5% agreement
was observed for the 94 NTM isolates identified by both methods. The MMSA provided
correct identification for 96.8% of the NTM isolates compared with 94.7% for
PRA-hsp65. The MMSA is a suitable auxiliary method for routine
use for the rapid identification of mycobacteria. 相似文献
54.
55.
Al-Ramamneh D Riek A Gerken M 《Animal : an international journal of animal bioscience》2012,6(1):173-178
The present study was conducted to evaluate and compare the physiological responses of sheep and goats to water restriction using the deuterium dilution technique (D2O) to predict the total water intake (TWI) in both species. In two consecutive trials, 10 non-lactating Boer goats and 10 non-lactating German black-head mutton ewes were each randomly allocated into a treatment and a control group. In the control groups (n = 5, for each species), water was offered ad libitum, whereas the treatment groups (n = 5, for each species) received water 3 h/day on experimental days 8 to 14 and 6 h every 2 days on experimental days 15 to 22. The respiratory rate, rectal temperature, body mass and drinking behaviour were also recorded. The TWI was estimated by D2O for each animal. Water restriction for 21 h/day or 42 h/2 days had no significant (P > 0.05) effect on water intake (WI), feed intake, WI to dry matter intake ratio or body mass in both species. The absence of differences between species in their WIs was also confirmed using D2O. However, sheep had higher respiratory rates and rectal temperatures than goats in both control and treatment groups. Both species showed the ability to tolerate a moderate water shortage by activating several physiological mechanisms and behavioural strategies. 相似文献
56.
Alper PB Marsilje TH Mutnick D Lu W Chatterjee A Roberts MJ He Y Karanewsky DS Chow D Lao J Gerken A Tuntland T Liu B Chang J Gordon P Seidel HM Tian SS 《Bioorganic & medicinal chemistry letters》2008,18(19):5255-5258
A novel series of benzo[a]carbazole-based small molecule agonists of the thrombopoietin (Tpo) receptor is reported. Starting from a 3.4 microM high throughput screen hit, members of this series have been identified which are full agonists with functional potency <50 nM and oral bioavailability in mice. 相似文献
57.
Marcilio CP de Souto Ivan G Costa Daniel SA de Araujo Teresa B Ludermir Alexander Schliep 《BMC bioinformatics》2008,9(1):497
Background
The use of clustering methods for the discovery of cancer subtypes has drawn a great deal of attention in the scientific community. While bioinformaticians have proposed new clustering methods that take advantage of characteristics of the gene expression data, the medical community has a preference for using "classic" clustering methods. There have been no studies thus far performing a large-scale evaluation of different clustering methods in this context. 相似文献58.
Yang Claire Yang Karen Gerken Kristen Schorpp Courtney Boen Kathleen Mullan Harris 《Biodemography and social biology》2017,63(2):87-103
A growing literature has demonstrated a link between early-life socioeconomic conditions and adult health at a singular point in life. No research exists, however, that specifies the life course patterns of socioeconomic status (SES) in relation to the underlying biological processes that determine health. Using an innovative life course research design consisting of four nationally representative longitudinal datasets that collectively cover the human life span from early adolescence to old age (Add Health, MIDUS, NSHAP, and HRS), we address this scientific gap and assess how SES pathways from childhood into adulthood are associated with biophysiological outcomes in different adult life stages. For each dataset, we constructed standardized composite measures of early-life SES and adult SES and harmonized biophysiological measurements of immune and metabolic functioning. We found that the relative importance of early-life SES and adult SES varied across young, mid, and late adulthood, such that early-life SES sets a life course trajectory of socioeconomic well-being and operates through adult SES to influence health as adults age. We also documented evidence of the detrimental health effects of downward mobility and persistent socioeconomic disadvantage. These findings are the first to specify the life course patterns of SES that matter for underlying biophysiological functioning in different stages of adulthood. The study thus contributes new knowledge critical for improving population health by identifying the particular points in the life course at which interventions might be most effective in preventing disease and premature mortality. 相似文献
59.
William J Durham Yi-Ping Li Eric Gerken Mehran Farid Sandrine Arbogast Robert R Wolfe Michael B Reid 《Journal of applied physiology》2004,97(5):1740-1745
This study tested the hypothesis that skeletal muscle contraction activates nuclear factor-kappaB (NF-kappaB), a putative regulator of muscle protein breakdown. Muscle biopsies were obtained from the vastus lateralis of healthy humans before, immediately after, and 1 h after fatiguing resistance exercise of the lower limbs. Biopsies were analyzed for nuclear NF-kappaB DNA binding activity by using electrophoretic mobility shift assay. NF-kappaB activity, measured immediately after exercise, was less than preexercise activity; after 1-h recovery, activity returned to preexercise levels. In follow-up studies in adult mice, basal NF-kappaB activity varied among individual muscles. NF-kappaB activity in diaphragm fiber bundles was decreased after a 10-min bout of fatiguing tetanic contractions in vitro. NF-kappaB activity in soleus was increased by 12 days of unloading by hindlimb suspension; this increase was reversed by 10 min of fatiguing exercise. These data provide no support for our original hypothesis. Instead, acute fatiguing exercise appears to decrease NF-kappaB activity in muscle under a variety of conditions. 相似文献
60.
C Tietz F Jelezko U Gerken S Schuler A Schubert H Rogl J Wrachtrup 《Biophysical journal》2001,81(1):556-562
Spectroscopic and polarization properties of single light-harvesting complexes of higher plants (LHC-II) were studied at both room temperature and T < 5 K. Monomeric complexes emit roughly linearly polarized fluorescence light thus indicating the existence of only one emitting state. Most probably this observation is explained by efficient triplet quenching restricted to one chlorophyll a (Chl a) molecule or by rather irreversible energy transfer within the pool of Chl a molecules. LHC-II complexes in the trimeric (native) arrangement bleach in a number of steps, suggesting localization of excitations within the monomeric subunits. Interpretation of the fluorescence polarization properties of trimers requires the assumption of transition dipole moments tilted out of the symmetry plane of the complex. Low-temperature fluorescence emission of trimers is characterized by several narrow spectral lines. Even at lowest excitation intensities, we observed considerable spectral diffusion most probably due to low temperature protein dynamics. These results also indicate weak interaction between Chls belonging to different monomeric subunits within the trimer thus leading to a localization of excitations within the monomer. The experimental results demonstrate the feasibility of polarization sensitive studies on single LHC-II complexes and suggest an application for determination of the Chl transition-dipole moment orientations, a key issue in understanding the structure-function relationships. 相似文献