Pied flycatcher males were removed from 14 territories on the day when females laid their first egg to see if other males would adopt the brood. In most cases males avoided joining females that had ...already begun egg-laying. Only in three nests did new males arrive and aided the females in raising the young. Replacement males joined widowed females in the beginning of the nesting cycle and, therefore, may have sired some of the young in the brood they helped to raise. /// Самцы мухолвки-пеструшки были изъяты с 14 участков в день, когда самки откладывали первое яйцо, чтобы установить, как другие самцы примут потом-ство. В большинстве случаев самцы не объединялись с самками, уже начавши-ми яйцеклажку. Лишь в трех гнездах самцы поселились и помогали в выкарм-ливании птенцов. Замещенные самцы присоединились к самкам в начале цикла гнездования и, таким образом, возможно, могли быть производителями наибо-лее молодых птенцов в выводках, которые они помогали выкармливать.
Codakia orbicularis may obtain nutrients from chemoautolithotrophic bacteria. The chemical composition of the C. orbicularis was investigated because of this unusual source of nutrition, and because ...it is a human food source in the Caribbean. The lipid fraction of these molluscs is discussed in detail. Polyunsaturated fatty acids account for only 11-15% of the total fatty acids, and non-methylene interrupted dienes are present as high as 9.5%. Cholesterol represents about 45% of the total sterols present.
A parent bird feeding its young often has the potential to increase its effort depending on how much the other parent is prepared to work. For life-history reasons such as reduced confidence in ...paternity and higher mating success with age (Houston and Davies 1985), we could expect Pied Flycatcher males to be prepared to work less than females in feeding young. We tested this idea by measuring the feeding rates of males and females in monogamous pairs; and also by a removal experiment, to see how much more single parents were prepared to work than members of a pair. Unaided males or females raised fewer young, which were also of lower fledging weight, than did pairs. Single males increased their feeding efforts as much as single females, and in monogamous pairs both sexes had similar feeding rates, thus contradicting our expectation. The model of Houston and Davies (1985) assumes that increasing effort affects adult mortality only after the independence of the young. In reality, adults might die before that time, and then the joint interest of both parents in staying alive at least until the independence of young, may have led to the stable "agreement" of Pied Flycatcher mates in contributing equally to the feeding af nestlings.
While both society and astronomy have evolved greatly over the past fifty years, the academic institutions and incentives that shape our field have remained largely stagnant. As a result, the ...astronomical community is faced with several major challenges, including: (1) the training that we provide does not align with the skills that future astronomers will need, (2) the postdoctoral phase is becoming increasingly demanding and demoralizing, and (3) our jobs are increasingly unfriendly to families with children. Solving these problems will require conscious engineering of our profession. Fortunately, this Decadal Review offers the opportunity to revise outmoded practices to be more effective and equitable. The highest priority of the Subcommittee on the State of the Profession should be to recommend specific, funded activities that will ensure the field meets the challenges we describe.
We investigate the optical and Wide-field Survey Explorer (WISE) colors of "E+A" identified post-starburst galaxies, including a deep analysis of 190 post-starbursts detected in the 2 mu m All Sky ...Survey Extended Source Catalog. The post-starburst galaxies appear in both the optical green valley and the WISE Infrared Transition Zone. Furthermore, we find that post-starbursts occupy a distinct region of 3.4-4.6 versus 4.6-12 WISE colors, enabling the identification of this class of transitioning galaxies through the use of broadband photometric criteria alone. We have investigated possible causes for the WISE colors of post-starbursts by constructing a composite spectral energy distribution (SED), finding that the mid-infrared (4-12 mu m) properties of post-starbursts are consistent with either 11.3 mu m polycyclic aromatic hydrocarbon emission, or thermally pulsating asymptotic giant branch (TP-AGB) and post-AGB stars. The composite SED of extended post-starburst galaxies with 22 mu m emission detected with signal-to-noise ratio >= 3 requires a hot dust component to produce their observed rising mid-infrared SED between 12 and 22 mu m. The composite SED of WISE. 22 mu m non-detections (S/N < 3), created by stacking 22 mu m images, is also flat, requiring a hot dust component. The most likely source of the mid-infrared emission of these E+A galaxies is a buried active galactic nucleus (AGN). The inferred upper limits to the Eddington ratios of post-starbursts are 10(-2)-10(-4), with an average of 10(-3). This suggests that AGNs are not radiatively dominant in these systems. This could mean that including selections capable of identifying AGNs as part of a search for transitioning and post-starburst galaxies would create a more complete census of the transition pathways taken as a galaxy quenches its star formation.
Anaphylactic reaction from Ringer's solution Hannuksela, Matti; Alatalo, Elina; Tuominen, Esa K
Duodecim (Helsinki, Finland : 1961),
2004, Volume:
120, Issue:
10
Magazine Article
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