Chewing gum alleviates negative mood and reduces cortisol during acute laboratory psychological stress

The notion that chewing gum may relieve stress was investigated in a controlled setting. A multi-tasking framework which reliably evokes stress and also includes performance measures was used to induce acute stress in the laboratory. Using a randomised crossover design forty participants (mean age 21.98 years) performed on the multi-tasking framework at two intensities (on separate days) both while chewing and not chewing. Order of workload intensity and chewing conditions were counterbalanced. Before and after undergoing the platform participants completed the state portion of the State-Trait Anxiety Inventory, Bond-Lader visual analogue mood scales, a single Stress Visual Analogue Scale and provided saliva samples for cortisol measurement. Baseline measures showed that both levels of the multi-tasking framework were effective in significantly reducing self-rated alertness, calmness and contentment while increasing self-rated stress and state anxiety. Cortisol levels fell during both levels of the stressor during the morning, reflecting the predominance of a.m. diurnal changes, but this effect was reversed in the afternoon which may reflect a measurable stress response. Pre-post stressor changes (Delta) for each measure at baseline were subtracted from Delta scores under chewing and no chewing conditions. During both levels of stress the chewing gum condition was associated with significantly better alertness and reduced state anxiety, stress and salivary cortisol. Overall performance on the framework was also significantly better in the chewing condition. The mechanisms underlying these effects are unknown but may involve improved cerebral blood flow and/or effects secondary to performance improvement during gum chewing

Drawing Trees with Perfect Angular Resolution and Polynomial Area

We study methods for drawing trees with perfect angular resolution, i.e., with angles at each node v equal to 2{\pi}/d(v). We show: 1. Any unordered tree has a crossing-free straight-line drawing with perfect angular resolution and polynomial area. 2. There are ordered trees that require exponential area for any crossing-free straight-line drawing having perfect angular resolution. 3. Any ordered tree has a crossing-free Lombardi-style drawing (where each edge is represented by a circular arc) with perfect angular resolution and polynomial area. Thus, our results explore what is achievable with straight-line drawings and what more is achievable with Lombardi-style drawings, with respect to drawings of trees with perfect angular resolution.Comment: 30 pages, 17 figure

Reflecting on loss in Papua New Guinea

This article takes up the conundrum of conducting anthropological fieldwork with people who claim that they have 'lost their culture,' as is the case with Suau people in the Massim region of Papua New Guinea. But rather than claiming culture loss as a process of dispossession, Suau claim it as a consequence of their own attempts to engage with colonial interests. Suau appear to have responded to missionization and their close proximity to the colonial-era capital by jettisoning many of the practices characteristic of Massim societies, now identified as 'kastom.' The rejection of kastom in order to facilitate their relations with Europeans during colonialism, followed by the mourning for kastom after independence, both invite consideration of a kind of reflexivity that requires action based on the presumed perspective of another

A history of the Anglican mission in Papua, 1891-1941

The purpose of this thesis is to enquire into the aims, methods and achievements of the Anglican Mission in Papua between 1891 and 1941. This span of fifty years may conveniently be divided into three periods. In the first of these (1891 - 1910) missionaries made a foothold on the northern Papuan coast while their patrons attempted to secure for them a source of support. In the second period (1910-1920) the mission sought to define attitudes towards indigenous culture in harmony with contemporary colonial philosophy and traditional theology. The third period (1920-1941) saw a slowing down in missionary momentum as a result of diminishing support at home, at a time when Papuans were encountering other agencies of western culture. The work of the Anglican Mission is examined both in relation to the aspirations of its founders and the reactions of the Melanesians. Its struggle for survival and growth is set in the context of a society in transition. Since it is in the nature of missionary work to come to an end, leaving an integrated Christian culture behind, the methods used by missionaries to bring this about are evaluated, and in particular why some enterprises died and others flourished, where the mission failed to realize its goals and where it attained a measure of success. The mission entered northern Papua under the aegis of a powerful invading culture. The Papuan reaction to the invasion ranged from an eager reception of missionaries in some places to the waning of millenarian hopes in others. This varied as the Papuans attempted to relate missionaries both to other westerners and to their own experiences and philosophies of life. Lastly, the enquiry is directed towards the Papuan Christian as he moved slowly away from the guardianship of the missionary on the edge of civilization, as missionary and convert saw hopes for a golden age of Papuan missions dashed on the stubborn realities of cultural change

Cognitive-Behavioral Therapy Augmentation of SSRI Reduces Cortisol Levels in Older Adults with Generalized Anxiety Disorder: A Randomized Clinical Trial

Objectives: Elevated cortisol in stress and aging, such as has been seen in late-life anxiety disorders, is postulated to accelerate cognitive and physiological decline in this large and increasing population. Selective serotonin-reuptake inhibitors (SSRIs) and cognitive behavior therapy (CBT) are both effective treatments for Generalized Anxiety Disorder (GAD) in older adults. On the other hand, there is very little research examining the effect of combining these therapies on peak cortisol levels. For the current analyses, we examined the effectiveness of CBT augmentation on peak cortisol levels in older adults diagnosed with GAD. Methods: The sample consisted of 42 individuals with late-life GAD who received an acute course of the SSRI escitalopram and then entered a 16-week randomized phase. Twenty-one participants were randomized to receive 16 sessions of CBT in addition to continuing escitalopram and the remaining 21 participants continued on escitalopram without CBT. Generalized Estimating Equations were performed to assess the effectiveness of CBT augmentation on peak cortisol levels (30 minutes after waking). Results: Older adults with GAD who received both escitalopram and CBT demonstrated a significant reduction in peak cortisol levels at post-treatment compared to the group who received escitalopram without CBT augmentation. Conclusions: CBT augmentation of SSRI treatment reduced peak cortisol levels for older adults with GAD. Since persistently high cortisol levels in aging are thought to increase age-related cognitive and medical problems, our findings suggest that there may be a benefit to health and cognition of CBT augmentation for late-life anxiety disorders

Evaluating the diagnostic role of in-bore magnetic resonance imaging guided prostate biopsy: a single-centre study.

BACKGROUND To evaluate the role of in-bore MRI-guided biopsy (IB-MRGB) in the diagnosis of clinically significant prostate cancer (csPCa). METHODS In this tertiary single centre study, a total of 125 consecutive patients receiving IB-MRGB over a three-year period were evaluated, including 73 patients who had prior biopsies and 52 biopsy-naïve patients. We assessed cancer detection rate of patients according to the degree of suspicion based on mpMRI findings. Histopathological data were reviewed by experienced uropathologists. RESULTS The mpMRI was suspicious for PCa (PI-RADS 4/5) in 77% (96/125) and equivocal (PI-RADS 3) in 23% (29/125). The detection rate for csPCa was 54.2% (52/96) and 20.7% (6/29) for suspicious lesions (PI-RADS 4/5) and equivocal lesions (PI-RADS 3), respectively. In subgroup analysis, patients with previous negative biopsy, overall positive biopsy rate and csPCa detection rate were 48.3% (19/35) and 34.5% (13/35), respectively. In patients on AS, 36/44 (81.8%) and 21/44 (47.8%) had PCa and csPCa respectively. In biopsy-naïve patients 34/52 (65.4%) and 27/52 (51.92%) had PCa and csPCa respectively. Of the patients on AS, 18/44 (41.6%) upgraded from ISUP 1 to ISUP 2 PCa, and 4/44 (9.1%) upgraded from ISUP 1 to ISUP 3 PCa on IB-MRGB. A total of 14 Clavien-Dindo≤2 complications occurred in 14 patients (11.2%) that were directly related to the biopsy. No Clavien-Dindo≥3 complications occurred. CONCLUSION MRI-targeted biopsy is suitable for assessment of csPCa. Given the favourable complications profile, its use may be considered in both the initial biopsy and re-biopsy settings

Fatness but Not Fitness Linked to BrainAge: Longitudinal Changes in Brain Aging during an Exercise Intervention.

PURPOSE: Fitness, physical activity, body composition, and sleep have all been proposed to explain differences in brain health. We hypothesized that an exercise intervention would result in improved fitness and body composition and would be associated with improved structural brain health. METHODS: In a randomized controlled trial, we studied 485 older adults who engaged in an exercise intervention ( n = 225) or a nonexercise comparison condition ( n = 260). Using magnetic resonance imaging, we estimated the physiological age of the brain (BrainAge) and derived a predicted age difference compared with chronological age (brain-predicted age difference (BrainPAD)). Aerobic capacity, physical activity, sleep, and body composition were assessed and their impact on BrainPAD explored. RESULTS: There were no significant differences between experimental groups for any variable at any time point. The intervention group gained fitness, improved body composition, and increased total sleep time but did not have significant changes in BrainPAD. Analyses of changes in BrainPAD independent of group assignment indicated significant associations with changes in body fat percentage ( r (479) = 0.154, P = 0.001), and visceral adipose tissue (VAT) ( r (478) = 0.141, P = 0.002), but not fitness ( r (406) = -0.075, P = 0.129), sleep ( r (467) range, -0.017 to 0.063; P range, 0.171 to 0.710), or physical activity ( r (471) = -0.035, P = 0.444). With linear regression, changes in body fat percentage and VAT significantly predicted changes in BrainPAD ( β = 0.948, P = 0.003) with 1-kg change in VAT predicting 0.948 yr of change in BrainPAD. CONCLUSIONS: In cognitively normal older adults, exercise did not appear to impact BrainPAD, although it was effective in improving fitness and body composition. Changes in body composition, but not fitness, physical activity, or sleep impacted BrainPAD. These findings suggest that focus on weight control, particularly reduction of central obesity, could be an interventional target to promote healthier brains

Cardiorespiratory Fitness and Sleep, but not Physical Activity, are Associated with Functional Connectivity in Older Adults.

BACKGROUND: Aging results in changes in resting state functional connectivity within key networks associated with cognition. Cardiovascular function, physical activity, sleep, and body composition may influence these age-related changes in the brain. Better understanding these associations may help clarify mechanisms related to brain aging and guide interventional strategies to reduce these changes. METHODS: In a large (n = 398) sample of healthy community dwelling older adults that were part of a larger interventional trial, we conducted cross sectional analyses of baseline data to examine the relationships between several modifiable behaviors and resting state functional connectivity within networks associated with cognition and emotional regulation. Additionally, maximal aerobic capacity, physical activity, quality of sleep, and body composition were assessed. Associations were explored both through correlation and best vs. worst group comparisons. RESULTS: Greater cardiovascular fitness, but not larger quantity of daily physical activity, was associated with greater functional connectivity within the Default Mode (p = 0.008 r = 0.142) and Salience Networks (p = 0.005, r = 0.152). Better sleep (greater efficiency and fewer nighttime awakenings) was also associated with greater functional connectivity within multiple networks including the Default Mode, Executive Control, and Salience Networks. When the population was split into quartiles, the highest body fat group displayed higher functional connectivity in the Dorsal Attentional Network compared to the lowest body fat percentage (p = 0.011; 95% CI - 0.0172 to - 0.0023). CONCLUSION: These findings confirm and expand on previous work indicating that, in older adults, higher levels of cardiovascular fitness and better sleep quality, but not greater quantity of physical activity, total sleep time, or lower body fat percentage are associated with increased functional connectivity within key resting state networks