Emotional response inhibition is greater in older than younger adults

Emotional information rapidly captures our attention and also often invokes automatic response tendencies, whereby positive information motivates approach, while negative information encourages avoidance. However, many circumstances require the need to override or inhibit these automatic responses. Control over responses to emotional information remains largely intact in late life, in spite of age-related declines in cognitive control and inhibition of responses to non-emotional information. The goal of this behavioral study was to understand how the aging process influences emotional response inhibition for positive and negative information in older adults. We examined emotional response inhibition in 36 healthy older adults (ages 60–89) and 44 younger adults (ages 18–22) using an emotional Go/No-Go task presenting happy (positive), fearful (negative), and neutral faces. In both younger and older adults, happy faces produced more approach-related behavior (i.e., fewer misses), while fearful faces produced more avoidance-related behavior, in keeping with theories of approach/avoidance-motivated responses. Calculation of speed/accuracy trade-offs between response times and false alarm rates revealed that younger and older adults both favored speed at the expense of accuracy, most robustly within blocks with fearful faces. However, there was no indication that the strength of the speed/accuracy trade-off differed between younger and older adults. The key finding was that although younger adults were faster to respond to all types of faces, older adults had greater emotional response inhibition (i.e., fewer false alarms). Moreover, younger adults were particularly prone to false alarms for happy faces. This is the first study to directly test effects of aging on emotional response inhibition. Complementing previous literature in the domains of attention and memory, these results provide new evidence that in the domain of response inhibition older adults may more effectively employ emotion regulatory ability, albeit on a slower time course, compared to younger adults. Older adults’ enhanced adaptive emotion regulation strategies may facilitate resistance to emotional distraction. The present study extends the literature of emotional response inhibition in younger adulthood into late life, and in doing so further elucidates how cognitive aging interacts with affective control processes

Chinese cross‐border mergers and acquisitions in the developing world: Is Africa unique?

China has emerged as an important partner for Africa. Not surprisingly, Chinese business and investment relations with Africa have been growing. This article contends that Africa offers a different proposition to Chinese business interests in non-African developing economies. In this optic, it takes a “comparative” institution-based view treating factors that determine Chinese multinationals' cross-border merger and acquisition (CBMA) decisions as comparatively different for Africa to the rest of the developing world. From a panel data estimation of the number of Chinese CBMAs from 2007 to 2016, we find among market size, natural resources, strategic assets, labor productivity, and institutional governance, only natural resources and market size have a distinctive effect, with Chinese investors being more attracted to African natural resources than the African market. The drive for natural resources provides impetus for Chinese MNEs to choose CBMAs over greenfield investment, and through majority ownership to exercise control. Our inference is that Africa is “significantly” different from other developing regions, in terms of CBMAs, as Chinese multinationals have a strong motive to control access to natural resources

Seeding black holes in cosmological simulations

We present a new model for the formation of black holes in cosmological simulations, motivated by the first star formation. Black holes form from high density peaks of primordial gas, and grow via both gas accretion and mergers. Massive black holes heat the surrounding material, suppressing star formation at the centres of galaxies, and driving galactic winds. We perform an investigation into the physical effects of the model parameters, and obtain a 'best' set of these parameters by comparing the outcome of simulations to observations. With this best set, we successfully reproduce the cosmic star formation rate history, black hole mass-velocity dispersion relation, and the size-velocity dispersion relation of galaxies. The black hole seed mass is ~103M{⊙}, which is orders of magnitude smaller than that which has been used in previous cosmological simulations with active galactic nuclei, but suggests that the origin of the seed black holes is the death of Population III stars.Peer reviewedFinal Accepted Versio

Fungal entomopathogens: new insights on their ecology

An important mechanism for insect pest control should be the use of fungal entomopathogens. Even though these organisms have been studied for more than 100 y, their effective use in the field remains elusive. Recently, however, it has been discovered that many of these entomopathogenic fungi play additional roles in nature. They are endophytes, antagonists of plant pathogens, associates with the rhizosphere, and possibly even plant growth promoting agents. These findings indicate that the ecological role of these fungi in the environment is not fully understood and limits our ability to employ them successfully for pest management. In this paper, we review the recently discovered roles played by many entomopathogenic fungi and propose new research strategies focused on alternate uses for these fungi. It seems likely that these agents can be used in multiple roles in protecting plants from pests and diseases and at the same time promoting plant growth

Galaxy Formation Theory

We review the current theory of how galaxies form within the cosmological framework provided by the cold dark matter paradigm for structure formation. Beginning with the pre-galactic evolution of baryonic material we describe the analytical and numerical understanding of how baryons condense into galaxies, what determines the structure of those galaxies and how internal and external processes (including star formation, merging, active galactic nuclei etc.) determine their gross properties and evolution. Throughout, we highlight successes and failings of current galaxy formation theory. We include a review of computational implementations of galaxy formation theory and assess their ability to provide reliable modelling of this complex phenomenon. We finish with a discussion of several "hot topics" in contemporary galaxy formation theory and assess future directions for this field.Comment: 58 pages, to appear in Physics Reports. This version includes minor corrections and a handful of additional reference

PREDICT-CP: study protocol of implementation of comprehensive surveillance to predict outcomes for school-aged children with cerebral palsy

Objectives: Cerebral palsy (CP) remains the world’s most common childhood physical disability with total annual costs of care and lost well-being of $A3.87b. The PREDICT-CP (NHMRC 1077257 Partnership Project: Comprehensive surveillance to PREDICT outcomes for school age children with CP) study will investigate the influence of brain structure, body composition, dietary intake, oropharyngeal function, habitual physical activity, musculoskeletal development (hip status, bone health) and muscle performance on motor attainment, cognition, executive function, communication, participation, quality of life and related health resource use costs. The PREDICT-CP cohort provides further follow-up at 8–12 years of two overlapping preschool-age cohorts examined from 1.5 to 5 years (NHMRC 465128 motor and brain development; NHMRC 569605 growth, nutrition and physical activity). Methods and analyses: This population-based cohort study undertakes state-wide surveillance of 245 children with CP born in Queensland (birth years 2006–2009). Children will be classified for Gross Motor Function Classification System; Manual Ability Classification System, Communication Function Classification System and Eating and Drinking Ability Classification System. Outcomes include gross motor function, musculoskeletal development (hip displacement, spasticity, muscle contracture), upper limb function, communication difficulties, oropharyngeal dysphagia, dietary intake and body composition, participation, parent-reported and child-reported quality of life and medical and allied health resource use. These detailed phenotypical data will be compared with brain macrostructure and microstructure using 3 Tesla MRI (3T MRI). Relationships between brain lesion severity and outcomes will be analysed using multilevel mixed-effects models. Ethics and dissemination: The PREDICT-CP protocol is a prospectively registered and ethically accepted study protocol. The study combines data at 1.5–5 then 8–12 years of direct clinical assessment to enable prediction of outcomes and healthcare needs essential for tailoring interventions (eg, rehabilitation, orthopaedic surgery and nutritional supplements) and the projected healthcare utilisation

Hypoxic Air Inhalation and Ischemia Interventions Both Elicit Preconditioning Which Attenuate Subsequent Cellular Stress In vivo Following Blood Flow Occlusion and Reperfusion

schemic preconditioning (IPC) is valid technique which elicits reductions in femoral blood flow occlusion mediated reperfusion stress (oxidative stress, Hsp gene transcripts) within the systemic blood circulation and/or skeletal muscle. It is unknown whether systemic hypoxia, evoked by hypoxic preconditioning (HPC) has efficacy in priming the heat shock protein (Hsp) system thus reducing reperfusion stress following blood flow occlusion, in the same manner as IPC. The comparison between IPC and HPC being relevant as a preconditioning strategy prior to orthopedic surgery. In an independent group design, 18 healthy men were exposed to 40 min of (1) passive whole-body HPC (FiO2 = 0.143; no ischemia. N = 6), (2) IPC (FiO2 = 0.209; four bouts of 5 min ischemia and 5 min reperfusion. n = 6), or (3) rest (FiO2 = 0.209; no ischemia. n = 6). The interventions were administered 1 h prior to 30 min of tourniquet derived femoral blood flow occlusion and were followed by 2 h subsequent reperfusion. Systemic blood samples were taken pre- and post-intervention. Systemic blood and gastrocnemius skeletal muscle samples were obtained pre-, 15 min post- (15PoT) and 120 min (120PoT) post-tourniquet deflation. To determine the cellular stress response gastrocnemius and leukocyte Hsp72 mRNA and Hsp32 mRNA gene transcripts were determined by RT-qPCR. The plasma oxidative stress response (protein carbonyl, reduced glutathione/oxidized glutathione ratio) was measured utilizing commercially available kits. In comparison to control, at 15PoT a significant difference in gastrocnemius Hsp72 mRNA was seen in HPC (−1.93-fold; p = 0.007) and IPC (−1.97-fold; p = 0.006). No significant differences were observed in gastrocnemius Hsp32 and Hsp72 mRNA, leukocyte Hsp72 and Hsp32 mRNA, or oxidative stress markers (p > 0.05) between HPC and IPC. HPC provided near identical amelioration of blood flow occlusion mediated gastrocnemius stress response (Hsp72 mRNA), compared to an established IPC protocol. This was seen independent of changes in systemic oxidative stress, which likely explains the absence of change in Hsp32 mRNA transcripts within leukocytes and the gastrocnemius. Both the established IPC and novel HPC interventions facilitate a priming of the skeletal muscle, but not leukocyte, Hsp system prior to femoral blood flow occlusion. This response demonstrates a localized tissue specific adaptation which may ameliorate reperfusion stress

Civil society leadership in the struggle for AIDS treatment in South Africa and Uganda

Includes abstract.Includes bibliographical references.This thesis is an attempt to theorise and operationalise empirically the notion of ‘civil society leadership’ in Sub-Saharan Africa. ‘AIDS leadership,’ which is associated with the intergovernmental institutions charged with coordinating the global response to HIV/AIDS, is both under-theorised and highly context-specific. In this study I therefore opt for an inclusive framework that draws on a range of approaches, including the literature on ‘leadership’, institutions, social movements and the ‘network’ perspective on civil society mobilisation. This framework is employed in rich and detailed empirical descriptions (‘thick description’) of civil society mobilisation around AIDS, including contentious AIDS activism, in the key case studies of South Africa and Uganda. South Africa and Uganda are widely considered key examples of poor and good leadership (from national political leaders) respectively, while the Treatment Action Campaign (TAC) and The AIDS Support Organisation (TASO) are both seen as highly effective civil society movements. These descriptions emphasise ‘transnational networks of influence’ in which civil society leaders participated (and at times actively constructed) in order to mobilise both symbolic and material resources aimed at exerting influence at the transnational, national and local levels