Both odor identification and ApoE-ε4 contribute to normative cognitive aging

Research indicates that apoliprotein E (ApoE) plays a role in the development of Alzheimer's disease (AD) and possibly in the cognitive decline associated with normative aging. More recently, researchers have shown that ApoE is expressed in olfactory brain structures, and a relationship among ApoE, AD, and olfactory function has been proposed. In the current analyses, we investigated the contribution of ApoE and odor identification in decline trajectories associated with normative cognitive aging in various domains, using longitudinal data on cognitive performance available from the Swedish Adoption/Twin Study of Aging. Data on both ApoE status and olfactory functioning were available from 455 individuals ranging in age from 50 to 88 years at the first measurement occasion. Odor identification was measured via a mailed survey. Cognitive performance was assessed in up to 5 waves of in-person testing covering a period of 16 years. Latent growth curve analyses incorporating odor identification and ApoE status indicated a main effect of odor identification on the performance level in three cognitive domains: verbal, memory, and speed. A main effect of ApoE on rates of decline after age 65 was found for verbal, spatial, and speed factors. The consistency of results across cognitive domains provides support for theories that posit central nervous system-wide origins of the olfaction-cognition-ApoE relationship; however, olfactory errors and APOE ε4 show unique and differential effects on cognitive trajectory features.     

Stimulation seeking and intelligence: a prospective longitudinal study

The prediction that high stimulation seeking 3-year-olds would have higher IQs by 11 years old was tested in 1,795 children on whom behavioral measures of stimulation seeking were taken at 3 years, together with cognitive ability at 11 years. High 3-year-old stimulation seekers scored 12 points higher on total IQ at age 11 compared with low stimulation seekers and also had superior scholastic and reading ability. Results replicated across independent samples and were found for all gender and ethnic groups. Effect sizes for the relationship between age 3 stimulation seeking and age 11 IQ ranged from 0.52 to 0.87. Findings appear to be the first to show a prospective link between stimulation seeking and intelligence. It is hypothesized that young stimulation seekers create for themselves an enriched environment that stimulates cognitive development.     

Examining the influence of group diversity on the functioning of community-based participatory research partnerships: A mixed methods study

Public health has endorsed the use of community-based participatory research (CBPR) to address health inequities involving diverse and marginalized communities. However, few studies have examined how group diversity among members of CBPR partnerships influenced how well the partnerships achieve their goals of addressing health inequities through equitable collaboration. We conducted secondary, convergent, mixed methods analysis to (1) evaluate the association between group diversity and participatory decision-making within CBPR partnerships, and (2) identify the perceived characteristics, benefits, and challenges of group diversity within CBPR partnerships. Using data from a cross-site study of federally funded CBPR partnerships, we analyzed and integrated data from surveys of 163 partnerships (n = 448 partners) and seven in-depth case study interviews (n = 55 partners). Quantitatively, none of the measured characteristics of group diversity was associated with participatory decision-making within the partnerships. Qualitatively, we found that partnerships mainly benefited from membership differences in functional characteristics (e.g., skillset) but faced challenges from membership differences in sociocultural characteristics (e.g., gender and race). The integrated findings suggest the need to further understand how emergent group characteristics and how practices that engage in group diversity contribute to collective functioning of the partnerships. Attention to this area can help promote health equity achievements of CBPR partnerships.     

Applicability of Scheil–Gulliver solidification model in real alloy: a case study with Cu-9wt%Ni-6wt%Sn alloy

The present work explores the possibilities of the application of Scheil–Gulliver equation in modelling the solidification of a real alloy. For this study, Cu-9 wt%Ni-6 wt%Sn alloy was chosen which exhibits profuse micro-segregation during solidification, and hence easy to quantify experimentally. Also, this alloy is spinodally strengthened high strength copper alloy and has industrial importance. In this study, thermodynamic assessment using Scheil–Gulliver solidification model was carried out. Subsequently, the assessed result was compared with the experimentally obtained results from energy-dispersive X-ray spectroscopy analysis, and a good agreement was observed between these results. Therefore, it could be concluded that the solidification of this particular alloy system can be modelled using Scheil–Gulliver equation.     

Instagram Use and Self-Objectification: The Roles of Internalization,Comparison, Appearance Commentary,and Feminism

The current study examined potential mediators (i.e., internalization of cultural standards of beauty, engaging in upward and downward appearance comparison, and receiving positive and negative appearance-related commentary), moderators (i.e., feminist beliefs), and moderated mediation of the links between Instagram (an electronic way to share visual images) use and self-objectification and body surveillance among 492 undergraduate women from the Southeast United States. Results revealed that internalization of cultural standards of beauty and engaging in upward appearance comparison uniquely mediated Instagram usage and self-objectification and body surveillance links. Additionally, findings from the moderation analyses indicated that the direct effect of Instagram usage on body surveillance was contingent on feminist beliefs, such that this relationship was only significant among women with lower and moderate feminist beliefs. This finding suggests that higher feminist beliefs play a buffering or protective role whereas lower feminist beliefs play an intensifying role. Implications and future directions are discussed.     

Trace and contextual fear conditioning is enhanced in mice lacking the α4 subunit of the GABAA receptor

The GABA_AR α4 subunit is highly expressed in the dentate gyrus region of the hippocampus at predominantly extra synaptic locations where, along with the GABA_AR δ subunit, it forms GABA_A receptors that mediate a tonic inhibitory current. The present study was designed to test hippocampus-dependent and hippocampus-independent learning and memory in GABA_AR α4 subunit-deficient mice using trace and delay fear conditioning, respectively. Mice were of a mixed C57Bl/6J X 129S1/X1 genetic background from α4 heterozygous breeding pairs. The α4-knockout mice showed enhanced trace and contextual fear conditioning consistent with an enhancement of hippocampus-dependent learning and memory. These enhancements were sex-dependent, similar to previous studies in GABA_AR δ knockout mice, but differences were present in both males and females. The convergent findings between α4 and δ knockout mice suggests that tonic inhibition mediated by α4βδ GABA_A receptors negatively modulates learning and memory processes and provides further evidence that tonic inhibition makes important functional contributions to learning and behavior.     

Vibha Chaturvedi and Pragati Sahni (eds.): Understanding Ethics

Journal of Indian Council of Philosophical Research -