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Channel nuclear pore protein 54 directs sexual differentiation and neuronal wiring of female reproductive behaviors in Drosophila
No full textBackground: Female reproductive behaviors and physiology change profoundly after mating. The control of pregnancy-associated changes in physiology and behaviors are largely hard-wired into the brain to guarantee reproductive success, yet the gene expression programs that direct neuronal differentiation and circuit wiring at the end of the sex determination pathway in response to mating are largely unknown. In Drosophila, the post-mating response induced by male-derived sex-peptide in females is a well-established model to elucidate how complex innate behaviors are hard-wired into the brain. Here, we use a genetic approach to further characterize the molecular and cellular architecture of the sex-peptide response in Drosophila females. Results: Screening for mutations that affect the sensitivity to sex-peptide, we identified the channel nuclear pore protein Nup54 gene as an essential component for mediating the sex-peptide response, with viable mutant alleles leading to the inability of laying eggs and reducing receptivity upon sex-peptide exposure. Nup54 directs correct wiring of eight adult brain neurons that express pickpocket and are required for egg-laying, while additional channel Nups also mediate sexual differentiation. Consistent with links of Nups to speciation, the Nup54 promoter is a hot spot for rapid evolution and promoter variants alter nucleo-cytoplasmic shuttling. Conclusions: These results implicate nuclear pore functionality to neuronal wiring underlying the sex-peptide response and sexual differentiation as a response to sexual conflict arising from male-derived sex-peptide to direct the female post-mating response.This work was supported by the Biotechnology and Biological Science Research Council to MS and the Natural Sciences and Engineering Research Council of Canada to AC.https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-021-01154-
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Discounting Life: The Impact of Gender, Race, Domestic Violence, and Ideal Victim Status on Second Degree Murder Sentencing in Canada
Get PDFScholars, the media, and the public have been concerned about differing values placed on crime victims on the basis of social factors such as gender, race, and domestic violence affiliation. Some academics argue that specific victim attributes result in more punitive sentencing to be imposed, particularly if the victim is constructed as “ideal”. An ideal victim is one who is socially constructed as more “worthy” than another victim of crime based on personal attributes, behaviors and situational aspects of their victimization. International and domestic Canadian sentencing research, however, has demonstrated inconsistent results regarding the role of key victim attributes of gender, race and domestic violence status in sentencing. This study uses the theoretical perspective of social constructionism to guide an assessment of what impact victim gender, race, and domestic violence affiliation may have on sentencing and evaluate the effect of other “ideal victim” factors on court sanctions. The research design also considers the perspective of legal rationalism and the influence of legal factors such as past criminal history, as well as aggravating and mitigating circumstances considered by judges in their sentencing decision. The study uses the crime of second-degree murder and the outcome of parole ineligibility length to test research hypotheses. Through legal case reports and media coverage, data was gathered on victim and offender demographic, social situation and legal background data on 259 cases of second degree murder from 1980-2017. There was little support for the influence of race and domestic violence attributes on murder sentencing. Gender did appear to increase sentence punitivity, even after control variables were introduced. Consistent with past research, demographic factors and ideal victim situational factors showed mostly weak effects on sentencing, while legal predictors such as prior criminal history, other aggravating and mitigating factors explained considerably more variance in parole ineligibility. Given the high evidentiary burden of second degree murder and its seriousness as a crime, it may be an offence less likely to show bias at the point of sentence. Researchers investigating bias might be better served examining manslaughter, assault and less serious offences. Given the limited evidence of domestic violence bias, it may be that governments should provide more resources directly to family violence offenders for rehabilitation and victims for social support. Finally, results should be interpreted cautiously given sampling limitations.Social Sciences and Humanities Research Council (SSHRC)Master of Arts in Criminal Justic
Slides to accompany Chemistry and the Environment: A Chemistry Perspective for discussion of Environmental Issues [first edition]
No full textReproductive isolation caused by azoospermia in sterile male hybrids of Drosophila
No full textRecently diverged populations in the early stages of speciation offer an opportunity to understand mechanisms of isolation and their relative contributions. Drosophila willistoni is a tropical species with broad distribution from Argentina to the southern United States, including the Caribbean islands. A postzygotic barrier between northern populations (North America, Central America, and the northern Caribbean islands) and southern populations (South American and the southern Caribbean islands) has been recently documented and used to propose the existence of two different subspecies. Here, we identify premating isolation between populations regardless of their subspecies status. We find no evidence of postmating prezygotic isolation and proceeded to characterize hybrid male sterility between the subspecies. Sterile male hybrids transfer an ejaculate that is devoid of sperm but causes elongation and expansion of the female uterus. In sterile male hybrids, bulging of the seminal vesicle appears to impede the movement of the sperm toward the sperm pump, where sperm normally mixes with accessory gland products. Our results highlight a unique form of hybrid male sterility in Drosophila that is driven by a mechanical impediment to transfer sperm rather than by an abnormality of the sperm itself. Interestingly, this form of sterility is reminiscent of a form of infertility (azoospermia) that is caused by lack of sperm in the semen due to blockages that impede the sperm from reaching the ejaculate.HD and NS were partially funded by NSERC USRA scholarships. This work was supported by an NSERC Discovery Grant to AC.https://onlinelibrary.wiley.com/doi/10.1002/ece3.632
Re-routing using Contraction Hierarchies in Software-Defined Networks
Get PDFAccording to the Open Networking Foundation (ONF), one of the reasons to reexamine traditional network architectures is the increment of mobile devices and its data transmission. The global IP traffic forecast by CISCO estimates an overall traffic increase to 396 exabytes per month in 2022, more than three times the traffic on 2017 (122 exabytes per month). In this work, we research the similarities between vehicular networks and computer networks. These similarities will allow us to implement the Contraction Hierarchies algorithm (CH) in computer networks. CH is an interdisciplinary algorithm from vehicular networks which can provide us with the elements and logic to optimize specific routing problems in computer networks. In order to implement CH, we use Software Defined Networks (SDN). SDN is a computer networks paradigm that separates the Data and Control planes. The Data plane is left to the network devices to distribute the packages, and the control plane is centralized into a Controller. By having a controller with a broad view of the network, we implement CH in order to optimize route selection. Once the route is determined, we study the possibility of using the advantages of CH to redistribute traffic in case the network elements suffer from unforeseen circumstances.Master of Science in Applied Computer Scienc
Identifying the gaps: A scoping review of urban Indigenous health and wellness studies in Manitoba and Saskatchewan
Get PDFThe purpose of this paper is to review and summarize past urban Indigenous health and wellness studies conducted in Manitoba and Saskatchewan from 1996 to 2018 as part of a larger project to develop community-driven research platforms that focus on Indigenous health. Using the scoping review methodology, this paper presents literature from 13 databases in six categories: chronic disease, preventative and population health, maternal health, sexual health, traditional health and medicine, and the determinants of health proposed by the Public Health Agency of Canada (PHAC). This paper will be used as a first step to direct future research topics for communities and researchers by identifying research gaps."The University of Winnipeg Network Environment for Indigenous Health Research (NEIHR) Development Grant funded through the Canadian Institutes of Health Research (CIHR)."http://cjur.uwinnipeg.ca/index.php/cjur/article/view/292
