811 research outputs found
Nesting behaviour influences species-specific gas exchange across avian eggshells
Carefully controlled gas exchange across the eggshell is essential for the development of the avian embryo. Water vapour conductance (GH2O) across the shell, typically measured as mass loss during incubation, has been demonstrated to optimally ensure the healthy development of the embryo while avoiding desiccation. Accordingly, eggs exposed to sub-optimal gas exchange have reduced hatching success. We tested the association between eggshell GH2O and putative life-history correlates of adult birds, ecological nest parameters and physical characteristics of the egg itself to investigate how variation in GH2O has evolved to maintain optimal water loss across a diverse set of nest environments. We measured gas exchange through eggshell fragments in 151 British breeding bird species and fitted phylogenetically controlled, general linear models to test the relationship between GH2O and potential predictor parameters of each species. Of our 17 life-history traits, only two were retained in the final model: wet-incubating parent and nest type. Eggs of species where the parent habitually returned to the nest with wet plumage had significantly higher GH2O than those of parents that returned to the nest with dry plumage. Eggs of species nesting in ground burrows, cliffs and arboreal cups had significantly higher GH2O than those of species nesting on the ground in open nests or cups, in tree cavities and in shallow arboreal nests. Phylogenetic signal (measured as Pagel's λ) was intermediate in magnitude, suggesting that differences observed in the GH2O are dependent upon a combination of shared ancestry and species-specific life history and ecological traits. Although these data are correlational by nature, they are consistent with the hypothesis that parents constrained to return to the nest with wet plumage will increase the humidity of the nest environment, and the eggs of these species have evolved a higher GH2O to overcome this constraint and still achieve optimal water loss during incubation. We also suggest that eggs laid in cup nests and burrows may require a higher GH2O to overcome the increased humidity as a result from the confined nest microclimate lacking air movements through the nest. Taken together, these comparative data imply that species-specific levels of gas exchange across avian eggshells are variable and evolve in response to ecological and physical variation resulting from parental and nesting behaviours
Effect of castor oil hydrolysis in the production of gamma-decalactone by the yeast Yarrowia lipolytica
Archaeological investigations at the Ross Hammock site, Florida.
Describes the excavations of the Ross Hammock Site, located a little southeast of Oak Hill, Florida. The excavations were made in 1963 to evaluate the site\u27s archaeological potential. The authors believed that the site was probably occupied about 2000 years ago. Includes a brief account of an investigation of a nearby 19th century salt evaporation works site.https://stars.library.ucf.edu/floridaheritage/1007/thumbnail.jp
The effect of hydrodynamic conditions in Corynebacterium glutamicum growth
[Excerpt] Corynebacterium glutamicum is a facultative anaerobic, gram-positive bacterium with a GRAS status that grows fast and achieves high cell densities. C. glutamicum is commonly used in amino acids production, and is also able to convert sugars in organic acids (OA) and alcohols in specific conditions: anaerobic and limited-oxygen environments. In these conditions, the carbon metabolism is modified, namely the flux shifts from the pentose phosphate pathway to glycolysis and the TCA cycle flux decreases and consequently bacterial growth is strongly affected [1,2]. (...
A qualitative enquiry of health care workers’ narratives on knowledge and sources of information on principles of Respectful Maternity Care (RMC)
Research from sub-Saharan Africa indicate that many women experience varied forms of disrespectful maternity care, which amount to a violation of their rights and dignity. Notably, there is little research that sheds light on health care workers (HCWs) training and knowledge of principles of respectful maternity care (RMC). Formulating appropriate interventional strategies to promote the respectful provision of services for women during pregnancy, childbirth, and postpartum period requires an understanding of the current state of knowledge and sources of information on respectful maternity care among HCWs. This paper reports findings from a qualitative study that examined the knowledge and sources of information on the Respectful Maternity Care Charter among HCWs in rural Kisii and Kilifi counties in Kenya. Between January and March 2020, we conducted 24 in-depth interviews among HCWs in rural Kisii and Kilifi health facilities. Data were analyzed using a mixed deductive and inductive thematic analysis guided by Braun’s [2006] six stages of analysis. We found that from the seven globally accepted principles of respectful maternity care, at least half of the HCWs were aware of patients right to consented care, confidentiality and privacy, and the right to non-discriminatory care based on specific attributes. Knowledge of the right to no physical and emotional abuse, abandonment of care, and detentions in the facilities was limited to a minority of health care workers but only after prompting. Sources of information on respectful maternity care were largely limited to continuous medical and professional training and clinical mentorship. The existing gap shows the need for training and mentorship of HCWs on the Respectful Maternity Care Charter as part of pre-service medical and nursing curricula and continuing clinical education to bridge this gap. At the policy level, strategies are necessary to support the integration of respectful maternity care into pre-service training curricula
A TAXONOMIC REVISION OF THE GENUS HUXLEYA EWART (VERBENACEAE)*
Abstract A taxonomic revision of the monotypic genus Huxleya is presented and its affinities and distribution are considered. A detailed description of the type species, H. linifolia, is supplemented by a habit sketch of a flowering branch and analytical drawings of the flower. Taxonomic History of the Genus The genus Huxleya was described b
THE DROSERA PELTATA -D. AURICULATA COMPLEX
Abstract The correct authority of Drosera pehata is shown to be Thunberg and a specimen on Herb. Thunberg 7720 (UPS) is chosen as the new lectotype of this species. D. pe/tata and D. auriculata are variable taxa which consistently intergrade in parts of their wide range. As a consequence, D. auriculata is reduced to a subspecies of D. pe/tata. A description of D. pe/tata, a key to the two subspecies and descriptions of each are presented
NOTES ON HIBBERTIA (DILLENIACEAE) 4. THE IDENTITY OF H. ENERVIA
Abstract A specimen inscribed "New Holland Gov. King" (G) is identified as the type of Pleurandra enervia DC., which is then placed into synonomy of Hibbertia procumbens (Labill.) DC. New combinations, H. hemignosta (Steud.) J.R.Wheeler and H. hibbertioides (Steud.) J.R.Wheeler, are published to replace the Western Australian species previously identified as H. enervia. History CandoIle (1817) described 41 species which are now included in the genus Hibbertia and there is a type specimen for each of them in his own herbarium except for Pleurandra enervia, the identity of which remained a problem. It was based on a King specimen in Lambert's herbarium, and this was assumed lost with the sale and distribution of that collection in June 1842
The extreme insular adaptation of Garganornis ballmanni Meijer, 2014: A giant anseriformes of the Neogene of the Mediterranean basin
Macromolecule uptake and characterisation of hydrogels designed for gingival crevicular fluid sampling for periodontal disease diagnostics.
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