Conditioned taste aversions support drug discrimination learning at low dosages of morphine.

The present experiment shows that a conditioned taste aversion procedure can support discrimination learning at dosages of morphine comparable to those required to produce motivational effects. Sprague-Dawley rats were injected with 4.0 mg/kg morphine sulfate prior to a saccharin-lithium chloride pairing, and physiological saline prior to a saccharin-saline pairing. The rats avoided the saccharin solution following the administration of morphine and consumed significantly more saccharin following saline administration after four discrimination cycles. After this initial discrimination the subjects were trained with progressively lower doses of morphine. Discrimination learning was apparent at doses of 2.0, 1.5, 1.0, 0.75 and 0.5 mg/kg. Animals initially trained with 1.0 mg/kg morphine also learned the discrimination but required 10 training cycles. After this initial discrimination the subjects were trained with progressively lower dosages of morphine and showed a discrimination at a dosage of 0.5 mg/kg.     

Low-dimensional chaos maps learning in a model neuropil (olfactory bulb).

Quantification of a chaotic system can be made by calculating the correlation dimension (D2) of the data that the system generates (Packard et al., 1980). The D2 algorithm, however, requires stationarity of the generator, a feature that biological data rarely reflect (Mayer-Kress et al., 1988). So we developed the "point correlation dimension" (PD2), an algorithm that accurately tracks D2 in linked data of different dimensions (Carpeggiani et al., 1991). We now present a mathematical argument that, for stationary data, individual PD2s converge to D2 and we demonstrate that the algorithm rejects contributions made by bursts of noise. Data were obtained from the surface of the olfactory bulb of the conscious rabbit (64 electrodes, 640 Hz each, 1.3 sec epochs) before and after presentation of a novel or habituated odor. D2 could be calculated in only 1 of 10 novel-odor trials, whereas PD2 could be calculated in all. Both algorithms indicated that a novel odor evokes a spatially uniform dimensional increase. The PD2 uniquely exhibited the dimensional decreases that occur during inspiration and the gradients of mean dimension present during the nonstimulated control state. These control gradients remained unchanged without odor experience, but showed spatially specific PD2 increases following odor habituation. It is interpreted that, 1) the PD2 is sensitive, accurate, and appropriate for dimensional assessment of biological data, 2) that during analysis of unfamiliar information a single global process is transiently evoked in the neuropil, and 3) after experience multiple spatially specific processes tonically map the sites of learning.     

Low-dimensional chaos maps learning in a model neuropil (olfactory bulb)

Quantification of a chaotic system can be made by calculating the correlation dimension (D2) of the data that the system generates (Packard et al., 1980). The D2 algorithm, however, requires stationarity of the generator, a feature that biological data rarely reflect (Mayer-Kress et al., 1988). So we developed the “point correlation dimension” (PD2), an algorithm that accurately tracks D2 in linked data of different dimensions (Carpeggiani et al., 1991). We now present a mathematical argument that, for stationary data, individual PD2s converge to D2 and we demonstrate that the algorithm rejects contributions made by bursts of noise. Data were obtained from the surface of the olfactory bulb of the conscious rabbit (64 electrodes, 640 Hz each, 1.3 sec epochs) before and after presentation of a novel or habituated odor. D2 could be calculated in only 1 of 10 novel-odor trials, whereas PD2 could be calculated in all. Both algorithms indicated that a novel odor evokes a spatially uniform dimensional increase. The PD2 uniquely exhibited the dimensional decreases that occur during inspiration and the gradients of mean dimension present during the nonstimulated control state. These control gradients remained unchanged without odor experience, but showed spatially specific PD2 increases following odor habituation. It is interpreted that, 1) the PD2 issensitive, accurate, and appropriate for dimensional assessment of biological data, 2) that during analysis of unfamiliar information a singleglobal process is transiently evoked in the neuropil, and 3) after experience multiplespatially specific processes tonically map the sites of learning. Grant Support: National Institutes of Health, HL 31164 and NS27745     

Counselling issues in the fostering and adoption of children at risk of HIV infection

The heterosexual nature of the HIV epidemic in Lothian is such that a number (50 to date) of babies have been born to women who have HIV. Some have needed social work services such as Children Centre placement, foster parents or adopters. Since this work began in 1986, our understanding of the transmission and manifestation of HIV infection in children has grown. However, it is still not possible until children reach the age of two to be certain whether or not they have been infected, or what the outlook is for them. Even then there are some further areas of uncertainty. We have developed a programme of preparation, training and support which has enabled a number of families to live with this uncertainly in offering placements to children at risk of HIV infection.     

#sustainablefashion on Instagram: A content and network analysis of user-generated posts

The social and environmental impacts of the global fashion industry face increasing scrutiny. As such, consumers and brands look towards ‘sustainable fashion’ for low-impact alternatives. Simultaneously, visual social media platforms such as Instagram have become prevalent places for fashion advertising and discourse. To investigate this under-researched area, the current study utilises visual content and social network analysis to explore how sustainable fashion is presented on Instagram, specifically: (a) what visual characteristics are present within sustainable fashion content, and (b) in what broader contexts and communities is discussion of sustainable fashion taking place? Posts included under the hashtag #sustainablefashion (N = 650) were inspected for visual characteristics, including type of clothing, presence of person, post setting, presence of nature, and post format. Most posts were photographs located indoors with no person and no nature-based elements. The hashtags used alongside #sustainablefashion were analysed with Gephi software to establish a social network and community groups of related topics. Network analysis revealed four key community groups: online-promotional, artisan-traditional, eco-ethical, and Malay-online-selling. Secondhand fashion also appeared to be the most prominent sustainable fashion alternative on Instagram. This study is one of the first to investigate the characteristics of user-generated #sustainablefashion content on Instagram. Whilst social media is a burgeoning avenue for research, existing studies primarily investigate how these platforms can be harnessed for advertising, rather than what users themselves are already posting. Implications for brands who use this platform and opportunities for future research are discussed.     

Intra- and interpersonal factors and adolescent wellbeing during COVID-19 in three countries

COVID-19 has altered adolescents' opportunities for developing and strengthening interpersonal skills and proficiencies. Using data from adolescents in Italy, the United States, and the United Kingdom, we examined the relation between internalizing symptoms assessed pre-pandemic or when pandemic-related restrictions were lifted (Time 1) and associated internalizing symptoms during a subsequent restrictive pandemic period (Time 2). Across all 3 countries, we found significant and consistent effect sizes in the relation between Time 1 and Time 2 internalizing symptoms. We further examined the direct and moderating impact of self-efficacy and contextual supports for adolescents' internalizing symptoms. Higher self-efficacy was associated with lower levels of internalizing symptoms at Time 2 in all 3 countries. Additionally, the relation between Time 1 and 2 internalizing symptoms was buffered by regulatory self-efficacy and peer support in Italy, but in the U.S., higher levels of general self-efficacy instead had an exacerbating effect on the relation between Times 1 and 2 internalizing symptoms. Results are discussed in the context of utilizing cross-national datasets to examine similarities in adolescent well-being over time and in the face of varying government responses to the pandemic.