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1.
Aust Educ Res ; : 1-22, 2022 Jun 28.
Article in English | MEDLINE | ID: mdl-35789682

ABSTRACT

Publishing in the academy is a high-stakes activity often used to measure academic staff progress and inform promotion. Many universities have increased pressure on academics, even at the earliest stages of their careers, to publish in high-ranking journals resulting in increased stress and uncertainty. The authors of this paper are members of a writing group in an Australian regional university, established to support each other towards success in quality research and publishing. Over the 2020-2021 summer semester, six members of the group decided to reflect on their experiences, emotions and outcomes throughout the writing process by participating in four reflective arts-based activities. Theoretical frameworks of reflection and metaphor were used to share findings. Strong evidence of having to grapple with meeting university expectations in tension with personal goals and passions was ever-present. The importance of drawing on both personal resources and significant others to manage these tensions through self-care practices was also evident. Implications resulting from this research include recognising the pressures placed on academics to publish only in specifically ranked journals. Overall, the arts-based reflection was critical in uncovering deeper feelings about the pressures of publishing and supporting higher education employees' well-being and self-care during the writing process.

2.
PLoS Comput Biol ; 14(10): e1006455, 2018 10.
Article in English | MEDLINE | ID: mdl-30303951

ABSTRACT

The morphogenesis of sex combs (SCs), a male trait in many species of fruit flies, is an excellent system in which to study the cell biology, genetics and evolution of a trait. In Drosophila melanogaster, where the incipient SC rotates from horizontal to a vertical position, three signal comb properties have been documented: length, final angle and shape (linearity). During SC rotation, in which many cellular processes are occurring both spatially and temporally, it is difficult to distinguish which processes are crucial for which attributes of the comb. We have used a novel approach combining simulations and experiments to uncover the spatio-temporal dynamics underlying SC rotation. Our results indicate that 1) the final SC shape is primarily controlled by the inhomogeneity of initial cell size in cells close to the immature comb, 2) the final angle is primarily controlled by later cell expansion and 3) a temporal sequence of cell expansion mitigates the malformations generally associated with longer rotated SCs. Overall, our work has linked together the morphological diversity of SCs and the cellular dynamics behind such diversity, thus providing important insights on how evolution may affect SC development via the behaviours of surrounding epithelial cells.


Subject(s)
Animal Structures/growth & development , Drosophila melanogaster/growth & development , Epithelial Cells/physiology , Morphogenesis/physiology , Algorithms , Animals , Computational Biology , Epithelial Cells/cytology , Male
3.
Int Rev Cell Mol Biol ; 315: 153-81, 2015.
Article in English | MEDLINE | ID: mdl-25708463

ABSTRACT

In this review we examine the role of self-organization in the context of the evolution of morphogenesis. We provide examples to show that self-organized behavior is ubiquitous, and suggest it is a mechanism that can permit high levels of biodiversity without the invention of ever-increasing numbers of genes. We also examine the implications of self-organization for understanding the "internal descriptions" of organisms and the concept of a genotype-phenotype map.


Subject(s)
Biological Evolution , Heredity , Animals , Genetic Variation , Growth and Development , Humans , Models, Biological , Phenotype
4.
Proc Natl Acad Sci U S A ; 111(39): E4103-9, 2014 Sep 30.
Article in English | MEDLINE | ID: mdl-25197080

ABSTRACT

In spite of the diversity of possible biological forms observed in nature, a limited range of morphospace is frequently occupied for a given trait. Several mechanisms have been proposed to explain this bias in the distribution of phenotypes including selection, drift, and developmental constraints. Despite extensive work on phenotypic bias, the underlying developmental mechanisms explaining why particular regions of morphological space remain unoccupied are poorly understood. To address this issue, we studied the sex comb, a group of modified bristles used in courtship that shows marked morphological diversity among Drosophila species. In many Drosophila species including Drosophila melanogaster, the sex comb rotates 90° to a vertical position during development. Here we analyze the effect of changing D. melanogaster sex comb length on the process of rotation. We find that artificial selection changes the number of bristles per comb without a proportional change in the space available for rotation. As a result, when increasing sex comb length, rather than displaying a similar straight vertical shape observed in other Drosophila species, long sex combs bend because rotation is blocked by a neighboring row of bristles. Our results show ways in which morphologies that would be favored by natural selection are apparently impossible to achieve developmentally. These findings highlight the potential role of development in modifying selectable variation in the evolution of Drosophila sex comb length.


Subject(s)
Biological Evolution , Drosophila/anatomy & histology , Drosophila/genetics , Animal Structures/anatomy & histology , Animal Structures/growth & development , Animals , Drosophila/growth & development , Drosophila melanogaster/anatomy & histology , Drosophila melanogaster/genetics , Drosophila melanogaster/growth & development , Extremities/anatomy & histology , Male , Morphogenesis , Phenotype , Phylogeny , Selection, Genetic , Sex Characteristics , Species Specificity
5.
Eur J Cardiovasc Nurs ; 13(5): 466-72, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24336239

ABSTRACT

BACKGROUND: In patients undergoing coronary angiography or percutaneous coronary intervention (PCI), the standard post procedure regime includes immobilization and bed rest despite the use of vascular closure devices. AIM: In the Mobilization after Coronary Angiography or Percutaneous Coronary Intervention (MOBS) study we compared bleeding complications after cardiac catheterization with femoral artery access after mobilization immediately off the angiographic table or standard care with1 hour (MOBS I after a diagnostic angiogram) or 2 hours of bed rest before mobilization (MOBS II after PCI). METHODS: Bleeding complications were defined as major (requiring surgery of the femoral artery, transfusion or increased hospital stay) and minor (hematoma <5 × 5 cm(2), oozing from the puncture site or minor bleeding that could be compressed manually). RESULTS: In the MOBS I cohort (100 patients were mobilized immediately and 100 patients followed standard care) no major bleeding complications were seen. In the immediate mobilization group 2.0% experienced minor bleeding compared to 4.0% in the standard care group (p=0.41). In the MOBS II cohort after PCI (158 patients were mobilized immediately and 161 patients followed standard care), major bleeding complication rates did not differ significantly between the two groups: immediate mobilization group 26.6% vs. standard care group 28.0%, p=0.78. The majority of bleeding complications were due to oozing: immediate mobilization group 22.8% vs. standard care group 20.5%, p=0.62. CONCLUSIONS: Immediate mobilization after a coronary angiogram or PCI with the femoral access site closed by the closure device AngioSeal was not associated with increased bleeding risk compared to standard care with bed rest.


Subject(s)
Coronary Angiography/adverse effects , Coronary Angiography/methods , Hemorrhage/etiology , Hemorrhage/prevention & control , Immobilization/methods , Percutaneous Coronary Intervention/adverse effects , Percutaneous Coronary Intervention/methods , Aged , Bed Rest , Cohort Studies , Female , Hemostasis , Humans , Male , Middle Aged , Sweden , Vascular Closure Devices
6.
Mycology ; 4(4): 187-195, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24605248

ABSTRACT

Lichens can either disperse sexually through fungal spores or asexually through vegetative propagules and fragmentation. Understanding how genetic variation in lichens is distributed across a landscape can be useful to infer dispersal and establishment events in space and time as well as the conditions needed for this establishment. Most studies have sampled lichens across large spatial distances on the order of hundreds of kilometers, while here we sequence the internal transcribed spacer (ITS) for 113 samples of three Peltigera species sampling at a variety of small spatial scales. The maximum distance between sampled lichens was 3.7 km and minimum distance was approximately 20 cm. We find significant amounts of genetic diversity across all three species. For P. praetextata, two out of the three most common ITS genotypes exhibit spatial autocorrelation supporting short-range dispersal. Using rarefaction we estimate that all ITS genotypes in our sampling area have been found for P. praetextata and P. evansiana, but not P. canina. Comparing our results with other ITS data in the literature provides evidence for global dispersal for at least one sequence followed by the evolution of endemic haplotypes with wide dispersal and rare haplotypes with more local dispersal.

7.
Int Rev Cell Mol Biol ; 278: 119-48, 2009.
Article in English | MEDLINE | ID: mdl-19815178

ABSTRACT

The quest to understand the relationship between an organism's DNA sequence and three-dimensional form is an interdisciplinary task, integrating diverse fields of the life sciences. The relevance of the metaphor of a genotype-phenotype map is explored from a developmental perspective, in light of the recent concept of a "molecular toolkit" of protein-coding genes, and the widespread view that analyzing the logic and mechanics of gene regulation at multiple levels is key to explaining how morphology is genetically encoded. We discuss the challenges of decoding genomes despite variable genetic backgrounds, the dynamically changing physical and molecular contexts of the internal environment during development, and the impact of external forces on morphogenesis.


Subject(s)
Developmental Biology , Gene Expression Regulation, Developmental , Genes/physiology , Animals , Genotype , Humans , Phenotype
8.
Evol Dev ; 11(2): 191-204, 2009.
Article in English | MEDLINE | ID: mdl-19245550

ABSTRACT

The Drosophila sex comb (SC) has been hailed as a powerful tool for integrative studies in development, evolution, and behavior, but its ontogeny is poorly understood, even in the model organism Drosophila melanogaster. Using 4D live imaging and other techniques, we carried out a detailed analysis of the cellular events that take place during the development of the SC. We showed that the comb and other contiguous bristle formations assemble from noncontiguous precursor cells, which join together through intercalation. Most of the rotation of the SC (which has a longitudinal orientation in D. melanogaster but is initially transverse) occurs after this stage, when the structure is a single unit. We have provided evidence that male-specific convergent extension through cell rearrangement is responsible for both this rotation and another sexually dimorphic bristle trait. Contiguous bristle formations act as barriers to cell movement within the epithelium, and we demonstrated that a particularly rapid rotation of the proximal region of the comb is associated with the presence of a constricted area between a portion of the SC and a transverse row of contiguous bristle precursors. Our results suggest that the cell dynamics in the neighborhood of the SC may have biased its evolution.


Subject(s)
Drosophila melanogaster/physiology , Sex Characteristics , Animals , Biological Evolution , Evolution, Molecular , Extremities , Female , Gene Expression Regulation, Developmental , Green Fluorescent Proteins/metabolism , Male , Microscopy, Confocal/methods , Microscopy, Electron, Scanning , Morphogenesis , Phenotype
9.
Evol Dev ; 11(2): 205-18, 2009.
Article in English | MEDLINE | ID: mdl-19245551

ABSTRACT

The most complex and diverse secondary sexual character in Drosophila is the sex comb (SC), an arrangement of modified bristles on the forelegs of a subclade of male fruit flies. We examined SC formation in six representative nonmodel fruit fly species, in an effort to understand how the variation in comb patterning arises. We first compared SC development in two species with relatively small combs, Drosophila takahashii, where the SCs remain approximately transverse, and Drosophila biarmipes, where two rows of SC teeth rotate and move in an anterior direction relative to other bristle landmarks. We then analyzed comb ontogeny in species with prominent extended SCs parallel to the proximodistal axis, including Drosophila ficusphila and species of the montium subgroup. Our study allowed us to identify two general methods of generating longitudinal combs on the tarsus, and we showed that a montium subgroup species (Drosophila nikananu) with a comb convergently similar in size, orientation and position to the model organism Drosophila melanogaster, forms its SC through a different developmental mechanism. We also found that the protein product of the leg patterning gene, dachshund (dac), is strongly reduced in the SC in all species, but not in other bristles. Our results suggest that an apparent constraint on SC position in the adult may be attributable to at least two different lineage-specific developmental processes, although external forces could also play a role.


Subject(s)
Drosophila/physiology , Sex Characteristics , Animals , Body Patterning , Cell Lineage , Developmental Biology/methods , Extremities , Gene Expression Regulation, Developmental , Genes, Insect , Male , Microscopy, Confocal , Microscopy, Electron, Scanning , Phylogeny , Species Specificity
10.
J Genet ; 86(2): 111-23, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17968139

ABSTRACT

The putative regulatory relationships between Antennapedia (Antp), spalt major (salm) and homothorax (hth) are tested with regard to the sensitive period of antenna-to-leg transformations. Although Antp expression repressed hth as predicted, contrary to expectations, hth did not show increased repression at higher Antp doses, whereas salm, a gene downstream of hth, did show such a dose response. Loss of hth allowed antenna-to-leg transformations but the relative timing of proximal-distal transformations was reversed, relative to transformations induced by ectopic Antp. Finally, overexpression of Hth was only partially able to rescue transformations induced by ectopic Antp. These results indicate that there may be additional molecules involved in antenna/leg identity and that spatial, temporal and dosage relationships are more subtle than suspected and must be part of a robust understanding of molecular network behaviour involved in determining appendage identity in Drosophila melanogaster.


Subject(s)
Antennapedia Homeodomain Protein/genetics , Antennapedia Homeodomain Protein/physiology , Drosophila Proteins/genetics , Drosophila Proteins/physiology , Drosophila melanogaster/embryology , Drosophila melanogaster/genetics , Gene Expression Regulation, Developmental , Limb Deformities, Congenital/genetics , Animals , Animals, Genetically Modified , Body Patterning/genetics , Embryo, Nonmammalian , Gene Dosage/physiology , Gene Regulatory Networks/physiology , Genetic Complementation Test , Homeodomain Proteins/genetics , Models, Biological , Time Factors
11.
Evol Dev ; 6(2): 114-22, 2004.
Article in English | MEDLINE | ID: mdl-15009124

ABSTRACT

The morphogenetic field, a fundamental concept of classical embryology, is once again being invoked to describe developmental processes. Because the evolution of adult structures requires the modification of development, the ways in which morphogenetic fields can change over time may yield insights into evolutionary possibilities. We considered how the duplication/multiplication of a morphogenetic field in fruit flies, caused by the previously described obake (obk) mutation, is regulated by genetic and environmental factors. Mutations of genes in the canonical antenna-producing imaginal disc pathway suppressed duplication as expected, although the results suggested that other pathways might also be involved. Overgrowth mutations, expected to increase duplication, actually suppressed it. Mutations in the heat-shock protein gene Hsp83 did not uniformly enhance obk expressivity as hypothesized. Using third chromosomes extracted from wild-derived lines, natural genetic variation for modifiers of obk function was found to be extensive. Larval crowding suppressed the obk phenotype, but there was no evidence of trade-offs between body or head size and arista number. Our results suggest that a complex interplay of genetic and environmental factors in the regulation of fields may be responsible for ample natural variation in the expressivity of adult phenotypes, affording multiple opportunities for selection and evolutionary modification.


Subject(s)
Animal Structures/embryology , Drosophila Proteins/metabolism , Drosophila melanogaster/embryology , Gene Expression Regulation, Developmental , Phenotype , Alleles , Animals , Body Weights and Measures , Drosophila melanogaster/metabolism , Female , Genotype , Heat-Shock Proteins/metabolism , Morphogenesis , Mutation/genetics , Population Density
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