Effects of a high salt diet on blood pressure responses to acoustic stimuli in borderline hypertensive rats (BHR)

The borderline hypertensive rat (BHR) responds to environmental and dietary stressors with elevated blood pressure. The first two months of a high salt diet appear to be the time of greatest sensitivity to salt effects on the blood pressure of BHR. The current study was conducted to examine whether exposure to salt diets varying in duration for up to two months differentially affects baseline blood pressures (systolic, SBP, and diastolic, DBP) and blood pressure responses to novel acoustic stimuli in BHR and normotensive Wistar-Kyoto (WKY) rats. Male BHR and WKY were fed a control (1%) salt diet or a high (8%) salt diet for 1, 1.5, 2.5, or 8.5 weeks. SBP and DBP responses to an acoustic stimulus (85 dB, 3 kHz) were measured upon completion of the diets at 12 weeks of age. Ten acoustic trials (one stimulus/minute) were presented and blood pressure responses were recorded in 2-second blocks spanning the 10 seconds prior to and following stimulus presentation. BHR had higher resting SBP and DBP than WKY, and 8.5 weeks of 8 percent salt increased SBP markedly in BHR. SBP and DBP labilities in the initial trial were greater in BHR than WKY with high salt diet durations of 2.5 and 8.5 weeks producing greater lability in later trials. Few differences were noted in pressor responses, but BHR had more dramatic depressor responses than WKY in early trials, and BHR pressures had a more dramatic return to baseline. It appears that genetic history and salt diet can affect blood pressure lability and recovery in response to novel stimuli in genetically susceptible animals.     

Both exposure to a novel context and associative learning induce an upregulation of AKAP150 protein in mouse hippocampus

A-kinase anchoring protein 150 (AKAP150) is a multi-enzyme signaling complex that coordinates the action of PKA, PKC, and PP2B at neuronal membranes and synapses. We measured levels of AKAP150 protein in the hippocampus 6h after training mice in a contextual fear conditioning paradigm. In contextual fear conditioning mice learn to associate a context with a footshock presentation. Mice were divided in four experimental groups with different training protocols: naive, no footshock exposure, immediate footshock exposure, and footshock 3min after exposure to the context. We found that AKAP150 protein levels were increased upon exposing mice to the novel context independent of the training protocol. However, when the animals were habituated to the experimental context, only mice that learned to associate the context with the footshock showed an upregulation of AKAP150. We suggest that upregulated levels of AKAP150 contribute to processing the exposure to a novel context and associative learning.     

Pathways to adulthood and their precursors and outcomes

Norway has an extensive welfare system which may provide adolescents with many options and high levels of flexibility in terms of pathways to adulthood. This study aimed to describe Norwegian developmental pathways to adulthood, including changes in role statuses (such as living situations, education, work, marriage/cohabitation and parenthood) from 16 to 30 years of age, and their precursors and outcomes. Repeated measures latent class analysis of longitudinal data from 998 Norwegian individuals indicated three main pathways to adulthood among women and men. In both sexes, most individuals undertook a long period of education and postponed family formation. However, some individuals started working early, a group of women established families with partners and children early, and a group of men remained primarily single between 16 and 30 years of age. Furthermore, the results show that pathways to adulthood in Norway are surprisingly similar to pathways in other countries such as the US, UK and Finland. The results indicate that pathways to adulthood are influenced by social reproduction factors in a country with high levels of welfare benefits as well. In addition, the results suggest that pathways involving living with a partner and either higher education or work are associated with high life satisfaction at age 30.     

The Uncertainty Paradox: Perceived Threat Moderates the Effect of Uncertainty on Political Tolerance

People respond to dissimilar political beliefs in a variety of ways, ranging from openness and acceptance to closed‐mindedness and intolerance. While there is reason to believe that uncertainty may influence political tolerance, the direction of this influence remains unclear. We propose that threat moderates the effect of uncertainty on tolerance; when safe, uncertainty leads to greater tolerance, yet when threatened, uncertainty leads to reduced tolerance. Using independent manipulations of threat and uncertainty, we provide support for this hypothesis. This research demonstrates that, although feelings of threat and uncertainty can be independent, it is also important to understand their interaction.     

Social Media as Social Capital of LGB Individuals in Hong Kong: Its Relations with Group Membership,Stigma, and Mental Well‐Being

Social media are found to facilitate social information exchange among lesbian, gay, and bisexual (LGB) individuals who are subjected to social stigma. This study tested the protective role of LGB‐tailored social media uses and gratifications in promoting LGB group membership, which we hypothesized to reduce LGB stigma and enhance mental health among LGB individuals in Hong Kong. Based on a sample of 233 Chinese LGB individuals in Hong Kong, structural equation modeling showed evidence for our hypotheses, χ_(df=62)² = 88.20, GFI = 0.95, CFI = 0.98, NNFI = 0.98, SRMR = 0.07, RMSEA = 0.04. Community surveillance, identity expression, and emotional support on social media may promote mental health by instilling a sense of group membership and reducing stigma. Social media may build camaraderie and bolster resilience among LGB individuals that may otherwise be difficult in conservative regions.     

Assessing Agreement between the K10 and MHI-5 Measures of Psychological Wellbeing

Responses to the Kessler Psychological Distress Scale (K10) and the Mental Health Index-5 (MHI-5) mental health subscale of the Medical Outcomes Study Short Form (SF-36) survey cover broadly similar constructs. The aim of this paper is to use the equipercentile method to produce a concordance between K10 and MHI-5 across the whole score distribution. Comparisons were made using survey data from the Australian Longitudinal Study on Women’s Health (ALSWH) and the Household, Income and Labour Dynamics in Australia (HILDA) survey, which used both the K10 and the MHI-5 measures at the same time for the same participants. Agreement was assessed with Bland-Altman plots. The differences between MHI-5 scores and transformed K10 scores were assessed with paired t-tests. For the ALSWH data there is good agreement between MHI-5 scores and scores equated from the K10. The mean of the differences is −0.15 with standard deviation 10.8. Using the ALSWH transformation on the HILDA data for different age groups and genders, the mean differences ranged from 0.43 to 3.38 with corresponding standard deviations of 11.1 to 9.9. The concordance table was very similar to one obtained by the more complicated item response theory method. The results suggest that longitudinal surveys of the same respondents that previously used MHI-5 could adopt the K10 (or vice versa) without loss of comparability.

     

Captivity and habituation to humans raise curiosity in vervet monkeys

Animal Cognition - The cognitive mechanisms causing intraspecific behavioural differences between wild and captive animals remain poorly understood. Although diminished neophobia, resulting from a...