Multiple mechanisms mediate the suppression of motion vision during escape maneuvers in flying Drosophila

During voluntary behaviors, animals need to disable any reflexes that could interfere with the intended movements. With the optomotor response, flies stabilize a straight flight path by correcting for unintended deviations sensed as the panoramic motion of the surround. HS cells of the fly are thought to mediate optomotor responses to horizontal motion. During spontaneous flight turns, an efference copy acts on HS cells with the right sign to counteract the visual input elicited by the fly’s own behavior. Here, we investigated, whether looming-elicited turns in flying Drosophila have a similar effect on HS cells. We show that looming stimuli themselves can influence the processing of panoramic motion stimuli in HS cells and that an inhibitory efference copy suppresses excitatory motion responses during turns in both directions, but only in a subset of HS cells. Our findings support the notion that the processing of sensory information is finely tuned to behavioral context

Multiple mechanisms mediate the suppression of motion vision during escape maneuvers in flying Drosophila

Animals must be able to discriminate self-generated (reafferent) from external (exafferent) sensory input. Otherwise, the former could interfere with perception and behavioral actions. The way this can be achieved is through an efference copy, which suppresses reafferent sensory input. An example for this is the optomotor response of the fly. With the optomotor response, flies stabilize a straight flight path by correcting for unintended deviations, which they sense as visual motion of their surrounding or optic flow. HS cells of the fly are tuned to rotational optic flow and are thought to mediate optomotor responses to horizontal motion. It has been shown that during spontaneous turns, an efference copy influences the membrane potential of HS cells. Here we investigate the influence of an efference copy during looming-elicited evasive turns combined with a subsequent optomotor stimulus in Drosophila. We show that looming stimuli themselves can influence the processing of preferred-direction motion in HS cells. In addition, an efference copy can influence visual processing during saccades in both directions, but only in a subset of cells. Our study supports the notion that processing of sensory information is finely tuned and dependent on both stimulus history and behavioral context

Correction: CO2 induced phase transitions in diamine-appended metal-organic frameworks.

[This corrects the article DOI: 10.1039/C5SC01828E.]

Q(2) dependence of nuclear transparency for exclusive rho(0) production

Exclusive coherent and incoherent electroproduction of the rho(0) meson from H-1 and N-14 targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to the lifetime of hadronic fluctuations of the virtual photon, and squared four-momentum of the virtual photon (-Q(2)). The ratio of N-14 to H-1 cross sections per nucleon, called nuclear transparency, was found to increase (decrease) with increasing l(c) for coherent (incoherent) rho(0) electroproduction. For fixed l(c), a rise of nuclear transparency with Q(2) is observed for both coherent and incoherent rho(0) production, which is in agreement with theoretical calculations of color transparency

The emergency department as a holding environment : using object relations theory and institutional transference to explore schizophrenia and emergency department overuse

The purpose of this study was to explore if object relations theory and institutional transference can help explain why some people with schizophrenia overuse the emergency department (ED). Since deinstitutionalization, and the implementation of managed care, high utilization of the ED by people with mental illnesses has become an important, and controversial topic within medical and mental health settings. High utilization negatively impacts both ED staff members, and people with schizophrenia. Specifically, this study examined this phenomenon through the lens of object relations theory, and institutional transference. Object relations theory contributed to an understanding of social relationships in schizophrenia, and how poor object relations impacts the therapeutic alliance. The concept of a holding environment was used to examine the ED as a source of containment for those in crisis. Institutional transference helped to explain why people with schizophrenia may develop transference to the ED instead of transference to an individual therapist. Findings of this research highlight the importance of person-centered care for people with schizophrenia. This thesis calls for a reexamination of our traditional notions of therapy, and connection so that we may better serve those with schizophrenia