Probing the segregation of evoked and spontaneous neurotransmission via photobleaching and recovery of a fluorescent glutamate sensor

Synapses maintain both action potential-evoked and spontaneous neurotransmitter release, however, organization of these two forms of release within an individual synapse remains unclear. Here, we used photobleaching properties of iGluSnFR, a fluorescent probe that detects glutamate, to investigate the subsynaptic organization of evoked and spontaneous release. In non-neuronal cells and neuronal dendrites, iGluSnFR fluorescence is intensely photobleached and recovers via diffusion of non-photobleached probes within 10-seconds. After photobleaching, while evoked iGluSnFR events could be rapidly suppressed, their recovery required several hours. In contrast, iGluSnFR responses to spontaneous release were comparatively resilient to photobleaching, unless the complete pool of iGluSnFR was activated by glutamate perfusion. This differential effect of photobleaching on different modes of neurotransmission is consistent with a subsynaptic organization where sites of evoked glutamate release are clustered and corresponding iGluSnFR probes are diffusion restricted, while spontaneous release sites are broadly spread across a synapse with readily diffusible iGluSnFR probes.

The Connections Between Founders’ Social Network and Human Capital in Technology-Based New Ventures

This research examines the relationship between a founding team’s social network and the acquisition of its critical human capital. First, explicitly dealing with technology-based firms, we disaggregate the founder(s) social network into four sub-networks: academic, industry, finance, and personal (family and community). Then, we detail the relationship between these individual sub-networks and the acquisition of both technical and business skilled human capital. Our results confirm that individual sub-networks have a differential effect on acquiring both technical and business human capital.

Age Differences in the Use/Efficacy of Emotion Coping Strategies among Adults with Chronic Pain: A Scoping Review

Active coping strategies (e.g., exercise and pharmacological treatments) typically do not leave chronic pain patients completely pain-free. Therefore, individuals turn to emotion-focused strategies to cope with associated impairment and psychosocial consequences. General coping strategy use has been shown to differ by age. This scoping review explored age differences in the use and effectiveness of emotion-focused strategies in adults experiencing chronic pain. Studies were located via advanced searches in PubMed, PsycINFO, CINAHL, Embase, Web of Science, and Proquest Dissertations and Theses Global and referral. Two reviewers independently conducted abstract screenings and full-text extractions. Conflicts were discussed and resolved by the PI. We identified 15 studies that met our inclusion criteria, of which 14 met criteria for high methodologic quality. The majority of studies utilized the Coping Strategies Questionnaire to assess differential use of pain-coping strategies. The remaining studies used one of five other questionnaires. Only one study examined the differential effect of age on the efficacy of emotion-focused strategies. Five of the eight studies that examined hoping/prayer coping reported the strategy’s positive association with age. Age was not associated with ignoring pain or reinterpreting pain sensations in any of the eight studies in which these strategies were measured. We concluded that older age was associated with the use of praying/hoping as a means of coping with pain. No other consistent associations between age and other measured coping strategies were identified. Future research should account for auxiliary stressors and pain characteristics while investigating the differential effect of age on pain coping efficacy.