Scrapie pathology and its relationship to infectivity following intraocular infection

Different strains of scrapie can be distinguished by the characteristic pattern of vacuolar degeneration which develops in the murine brain, and by the length of the incubation period. The causal agent has not been identified, and the presence of infection within tissues can only be demonstrated by bioassay. In this study, the intraocular route of infection was exploited to examine the development of the pathology produced by six different scrapie strains, and to compare the pattern of lesion targeting within this well-studied anatomical system with the spread of infectivity. Scrapie incubation period is controlled by the murine Sine gene, which has two alleles; lesion development was recorded in both mouse genotypes following infection with several of the scrapie strains. The pattern of lesion development was found to correspond closely with the neuroanatomical pathways from retina via the optic nerve to the visual projection areas in the brain. The earliest lesions in all models appeared in the second half of the incubation period, and were confined to the visual projection areas on the contralateral side of the brain to the injected eye (there is almost complete decussation at the murine chiasma). The first lesions were seen either in the superior colliculus or the dorsal lateral geniculate nucleus, depending on the scrapie model; these are both major projections of the optic nerve. The pattern of subsequent lesions within the visual system also varied, gradually affecting both sides of the brain, until in the terminal mouse, the lesions were usually similar to those resulting from an intracerebral route of infection.The spread of infectivity following intraocular infection 2 was studied by bioassay of tissues throughout the incubation period. The rise in infectivity levels of ME7 scrapie correlated closely with the sequence of lesion targeting, although infectivity wsls detected much earlier in the incubation period. Several questions relating to the sites of replication, and the spread of infectivity were investigated by bioassay of appropriate tissues. The lower levels of infectivity in retinas from mice with an inherited retinal defect, compared to normal mice, suggested that the photoreceptor cells support scrapie replication; these cells are destroyed following infection with 79A scrapie. The Sine gene was shown to delay replication in the single neuronal relay to the superior colliculus by 50 - 60 days, suggesting that this gene acts on the transport and/or replication of infectivity. High levels of infectivity were found in the spleen following intraocular infection, indicating that inoculum escaping from the eye initiates replication in the lymphoreticular system. Similarly, disease could also be produced by conjunctival instillation of inoculum with no evidence of contralateral targeting of lesions.The way in which infectivity spreads within neurons was studied using serial enucleation after infection, alteration of retinal ganglion cell number in mice, and attempted modification of initial infection. Following serial enucleation of the infected eye, the lesion pattern and incubation periods with ME7 scrapie indicated that infectivity spread at a similar rate to that of slow axoplasmic transport. Preliminary results with two other scrapie strains show similar timings, suggesting that spread within axons is a passive process associated with normal cellular metabolism. This means that Sine gene control is exerted through its effect on replication rather than transport

Rural health and human rights - summary of a submission to the truth and reconciliation commission health sector hearings, 17 June 1997

No Abstract

Embarrassment as a Key Emotion in Young People Talking About Sexual Health

This paper highlights embarrassment as one of the often-ignored emotions of young people when it comes to discussing issues around sexual health. There have been many sexual health studies on knowledge, attitudes and behaviour of young people over the past two decades, but emotional aspects have been largely ignored, despite a growing literature in the sociology of emotion. A qualitative approach was adopted in the form of focus group discussions, which included questions on sex education, sexual health campaigns and formal and informal sources of sexual health information and advice. Focus groups were conducted in secondary schools in and around Edinburgh and Aberdeen as part of a four-year evaluation study of a Scottish Demonstration Project on young people's sexual health: 'Healthy Respect'. We conclude that is it important for policy makers and sexual health promoters to understand young people's notions of embarrassment. Not only are there elements of sex education that (some) young people perceive as embarrassing, they also sense embarrassment in those people providing them with sex education. Young people reported that both professionals (e.g. teachers and doctors) and their parents could be embarrassed about raising the topic of sexual health. Moreover, as one of the goals of sex education is to ensure an open and non-embarrassing attitude towards sex and sexuality, there is still a major gap between the aspirations of health educators and policy makers and the ways that young people experience such education.Sexual Health Services, Adolescence, School, Scotland, Emotion, Qualitative Research, Sex Education, Parents, Focus Groups, Relationships

Challenging the Glass Ceiling: Collaboration as the Key to Increasing the Number of Librarians of Color in Academic Libraries

Currently, libraries are engaged in creating environments that embrace diversity, equity and inclusion (DEI). This includes having candidates for hire submit statements regarding their approach to DEI and internal committees to look at policies and procedures regarding DEI. Also there is a lot of both internal and external training designed to help organizations and their members become more adept at creating environments with DEI in mind. What is often missed in all of this activity is how individual librarians, through mentorship and collaboration, can come together to foster DEI and support each other in success. This field report shows how two librarians, from different backgrounds and experiences came together to not only support each other through their regular work day, but elevate their partnership toward professional success and retention. The report provides recommendations for creating a more inclusive workplace through mentoring and collaboration

Patterns and Processes of Groundwater Invasion by Copepods in the Interior Low Plateaus of the United States

The copepod crustacean fauna collected from subterranean habitats, including caves, wells, and the hyporheos of streams in and near the Interior Low Plateaus of the United States is dominated by Cyclopoida, with 39 species, followed by Harpacticoida with 9, and Calanoida with 2. Nearly all of the harpacticoid and calanoid species are widespread, primarily surface-dwelling generalists. Fourteen of the cyclopoids, members of the genera Diacyclops, Itocyclops, Megacyclops, and Rheocyclops, are apparently obligate stygobionts or hyporheic. Several of the species that are more strongly modified for subterranean existence occur only in the more southern, unglaciated areas. Our sampling data support the hypothesis that the more specialized, groundwater-interstitial species have been unable to disperse into previously glaciated regions; whereas some, less-specialized species may have invaded groundwaters from surface habitats as the glaciers receded

Aeroallergens, Allergic Disease, and Climate Change: Impacts and Adaptation

Recent research has shown that there are many effects of climate change on aeroallergens and thus allergic diseases in humans. Increased atmospheric carbon dioxide concentration acts as a fertilizer for plant growth. The fertilizing effects of carbon dioxide, as well as increased temperatures from climate change, increase pollen production and the allergen content of pollen grains. In addition, higher temperatures are changing the timing and duration of the pollen season. As regional climates change, plants can move into new areas and changes in atmospheric circulation can blow pollen- and spore-containing dust to new areas, thus introducing people to allergens to which they have not been exposed previously. Climate change also influences the concentrations of airborne pollutants, which alone, and in conjunction with aeroallergens, can exacerbate asthma or other respiratory illnesses. The few epidemiological analyses of meteorological factors, aeroallergens, and allergic diseases demonstrate the pathways through which climate can exert its influence on aeroallergens and allergic diseases. In addition to the need for more research, there is the imperative to take preventive and adaptive actions to address the onset and exacerbation of allergic diseases associated with climate variability and change

First Records of Two Neotropical Species of Mesocyclops (Copepoda) from Yukon Territory: Cases of Passive Dispersal?

Two species of neotropical cyclopoid copepod crustaceans, Mesocyclops longisetus curvatus and Mesocyclops venezolanus, were collected from a pond at Shingle Point, Yukon Territory, Canada, in September 1974. This is the first record of M. longisetus curvatus north of the southern United States and the first record of M. venezolanus north of Honduras. We provide amplified descriptions of both species. Four additional congeners, M. americanus, M. edax, M. reidae, and M. ruttneri, are now known from the continental U.S. and Canada. We provide a key to the identification of the six species. We hypothesize that the specimens of M. longisetus curvatus and M. venezolanus may have been passively transported to Shingle Point by migrant shorebirds.Key words: Copepoda, Cyclopoida, Mesocyclops, new record, Yukon, neotropical, zoogeography, passive dispersal, identification keyEn septembre 1974, on a recueilli deux espèces de copépodes cyclopoïdes néogènes, Mesocyclops longisetus curvatus et Mesocyclops venezolanus, dans un étang situé à Shingle Point, dans le territoire du Yukon au Canada. Cela représente la première occurrence rapportée de M. longisetus curvatus au nord de la partie méridionale des États-Unis, et la première de M. venezolanus au nord du Honduras. On donne une description détaillée des deux espèces. On sait maintenant qu'il existe quatre autres congénères, M. americanus, M. edax, M. reida et M. ruttneri, aux États-Unis américains et au Canada. On fournit un code permettant d'identifier les six espèces. On émet l'hypothèse que les spécimens de M. longisetus curvatus et de M. venezolanus ont pu être transportés de façon passive à Shingle Point par des oiseaux de rivage migrateurs.Mots clés: copépodes, cyclopoïdes, Mesocyclops, nouvelle Occurrence rapportée, Yukon, néogène, zoogéographie, dispersion passive, code d'identificatio

The Planktonic Copepods of Coastal Saline Ponds of the Cayman Islands with Special Reference to the Occurrence of Mesocyclops ogunnus Onabamiro, an Apparently Introduced Afro-Asian Cyclopoid

Taxonomic analysis of the copepod specimens collected from 29 Cayman Island ponds revealed the presence of ten species including the nearly ubiquitous cyclopoid Apocyclops panamensis. This species was widespread throughout the islands, being collected at 27 of the sampling sites. Another common calanoid, Mastigodiaptomus nesus, occurred at nine sites on Grand Cayman and one on Cayman Brac. A cyclopoid of Afro-Asian origin, Mesocyclops ogunnus, was collected at two nearly fresh water sites on Grand Cayman and was considered to be a recent introduction. Because of its known adaptability to fluctuating environmental conditions, it is likely that M. ogunnus will successfully compete with and probably displace some of the native species and may become a dominant zooplankter on Grand Cayman

The Planktonic Copepods of Coastal Saline Ponds of the Cayman Islands with Special Reference to the Occurrence of Mesocyclops ogunnus Onabamiro, an Apparently Introduced Afro-Asian Cyclopoid

Taxonomic analysis of the copepod specimens collected from 29 Cayman Island ponds revealed the presence of ten species including the nearly ubiquitous cyclopoid Apocyclops panamensis. This species was widespread throughout the islands, being collected at 27 of the sampling sites. Another common calanoid, Mastigodiaptomus nesus, occurred at nine sites on Grand Cayman and one on Cayman Brac. A cyclopoid of Afro-Asian origin, Mesocyclops ogunnus, was collected at two nearly fresh water sites on Grand Cayman and was considered to be a recent introduction. Because of its known adaptability to fluctuating environmental conditions, it is likely that M. ogunnus will successfully compete with and probably displace some of the native species and may become a dominant zooplankter on Grand Cayman

Shifting contexts, shifting identities: a realist exploration of transnational mobility, change and identity construction in South African Higher Education expatriates in Abu Dhabi, UAE.

Positioned in relation to the globalization of higher education, this realist study is approached from an interest in identity and focuses on nine South African academics professional contexts in South Africa and Abu Dhabi, UAE. As the context of identity formation and emergence is always local, the intention of this research was never to generalize. Rather, in using Bhaskar’s critical realism as its underpinning philosophy, and Archer’s social realism, theories on self, personal and the development and attainment of social identity - her concept of analytical dualism and her morphogenetic framework, this qualitative case study was designed to explore how global and national powers and mechanism effected change in this sub-group of academic’s respective higher education sectors and institutions in post- 1994 South Africa and in Abu Dhabi between 2008 and 2016. The study suggests that participants perceived their academic roles and role-incumbent professional identities to have been negatively impacted by the changes that were implemented in the South African higher education sector as a result the countries reintroduction to the global stage. Their response to become transnational educators in Abu Dhabi’s presented them with conditions that allied their professional experiences of the transformation of South African’s higher education sector. This led to a continued sense of loss of academic agency and powerlessness. This effecting the emergence, through the personal power of reflectivity, combined with discourse and affinity powers and mechanisms, in a social identity that supplanted their academic identities