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Green fluorescent protein (GFP) fluoresces efficiently under blue excitation despite major electrostatic rearrangements resulting from photoionization of the chromophore and neutralization of Glu-222. A competing phototransformation process, which ionizes the chromophore and decarboxylates Glu-222, mimics the electrostatic and structural changes in the fluorescence photocycle. Structural and spectroscopic analysis of the cryogenically stabilized photoproduct at 100 K and a structurally annealed intermediate of the phototransformed protein at 170 K reveals distinct structural relaxations involving protein, chromophore, solvent, and photogenerated CO2. Strong structural changes of the 100 K photoproduct after decarboxylation appear exclusively within 15 Å of the chromophore and include the electrostatically driven perturbations of Gln-69, Cys-70, and water molecules in an H-bonding network connecting the chromophore. X-ray crystallography to 1.85 Å resolution and static and picosecond time-resolved IR spectroscopy identify structural mechanisms common to phototransformation and to the fluorescence photocycle. In particular, the appearance of a 1697 cm-1 (+) difference band in both photocycle and phototransformation intermediates is a spectroscopic signature for the structural perturbation of Gin-69. This is taken as evidence for an electrostatically driven dynamic response that is common to both photoreaction pathways. The interactions between the chromophore and the perturbed residues and solvent are decreased or removed in the T203H single and T203H/Q69L double mutants, resulting in a strong reduction of the fluorescence quantum yield. This suggests that the electrostatic response to the transient formation of a buried charge in the wild type is important for the bright fluorescence. [ABSTRACT FROM AUTHOR]

Our access to computer-generated worlds changes the way we feel, how we think, and how we solve problems. In this review, we explore the utility of different types of virtual reality, immersive or non-immersive, for providing controllable, safe environments that enable individual training, neurorehabilitation, or even replacement of lost functions. The neurobiological effects of virtual reality on neuronal plasticity have been shown to result in increased cortical gray matter volumes, higher concentration of electroencephalographic beta-waves, and enhanced cognitive performance. Clinical application of virtual reality is aided by innovative brain–computer interfaces, which allow direct tapping into the electric activity generated by different brain cortical areas for precise voluntary control of connected robotic devices. Virtual reality is also valuable to healthy individuals as a narrative medium for redesigning their individual stories in an integrative process of self-improvement and personal development. Future upgrades of virtual reality-based technologies promise to help humans transcend the limitations of their biological bodies and augment their capacity to mold physical reality to better meet the needs of a globalized world. [ABSTRACT FROM AUTHOR]

Previous studies have clearly established the impact of culture on design creativity. For example, the presence of cultural values with low uncertainty avoidance (UA, the degree of anxiety and risk aversion that people feel during ambiguous situations) is linked to low workability of creative ideas. Currently, there is limited research on potential remedies to alleviate the impact of culture, specifically with respect to UA. Therefore, this study investigates the use of technology to prime UA cultural values and mitigate their potential negative impacts on design creativity. This was achieved using stimuli that had been generated by virtual reality (VR) technology and presented in an immersive environment. Participants in an experimental study were exposed to VR stimuli designed to either decrease or increase their UA. The results showed that the VR stimuli had successfully increased and decreased low and high UA values, respectively, which mitigated the influence of UA on design creativity. Furthermore, the VR stimuli influenced the emphasis of the participants on ideation, with lowered and enhanced UA values leading to them prioritizing novelty and usefulness, respectively. Overall, the findings provided evidence that VR could be leveraged from a psychological standpoint to reduce cultural influences on creativity through targeted priming. These findings indicated the essential implications of the study in terms of understanding the effect of immersive technologies in shaping human behaviors and mindsets. • Virtual reality stimuli can successfully prime the UA values of participants. • Primed high UA leads to a prioritization of the usefulness of ideas. • Primed low UA leads to a prioritization of the novelty of ideas. • VR stimuli is a promising tool for mitigating cultural influences on creativity. [ABSTRACT FROM AUTHOR]

The rebinding kinetics of CO to protoheme (FePPIX) in the presence and absence of a proximal imidazole ligand reveals the magnitude of the rebinding barrier associated with proximal histidine ligation. The ligation states of the heme under different solvent conditions are also investigated using both equilibrium and transient spectroscopy. In the absence of imidazole, a weak ligand (probably water) is bound on the proximal side of the FePPIX-CO adduct. When the heme is encapsulated in micelles of cetyltrimethylammonium bromide (CTAB), photolysis of FePPIX-CO induces a complicated set of proximal ligation changes. In contrast, the use of glycerol-water solutions leads to a simple two-state geminate kinetic response with rapid (10-100 ps) CO recombination and a geminate amplitude that can be controlled by adjusting the solvent viscosity. By comparing the rate of CO rebinding to protoheme in glycerol solution with and without a bound proximal imidazole ligand, we find the enthalpic contribution to the proximal rebinding barrier, Hp, to be 11 ± 2 kJ/mol. Further comparison of the CO rebinding rate of the imidazole bound protoheme with the analogous rate in myoglobin (Mb) leads to a determination of the difference in their distal free energy barriers: ΔGD 12± 1 kJ/mol. Estimates of the entropic contributions, due to the ligand accessible volumes in the distal pocket and the xenon-4 cavity of myoglobin (∼3 kJ/mol), then lead to a distal pocket enthalpic barrier of HD ≈ 9 ± 2 kJ/mol. These results agree well with the predictions of a simple model and with previous independent room-temperature measurements (Tian et al. Phys. Rev. Left. 1992, 68, 408) of the enthalpic MbCO rebinding barrier (18 ± 2 kJ/mol). [ABSTRACT FROM AUTHOR]

Advances in virtual reality present opportunities to relive experiences in an immersive medium that can change the way we perceive our life stories, potentially shaping our realities for the better. This paper studies the role of virtual reality as a tool for the creation of stories with the concept of the self as a narrator and the life of the self as a storyline. The basis of the study is the philosophical notion of the self-narrative as an explanatory story of the events in one's life that constitutes the notion of one's self. This application is suitable for cases when individuals need to recreate their self, such as during recovery after traumatic events. The analysis of the effects of virtual reality shows that it enables a person to engage in a process of deeper self-observation to understand and explain adverse events and to give meaning to these events to form a new story, which can complement the therapeutic outcomes of exposure treatments. This study proposes concrete examples of immersive scenarios used to reconstruct personal stories. Several possible levels of experience are proposed to suggest that recovery can be achieved through the gradual retelling of the self-narrative, addressing all of the underlying narratives. Considering the ethical challenges that might arise, this paper explores the ways in which immersion in virtual reality can benefit a person's view toward life as a story and his or her self as its author, comparing this idea with previous research on the application of virtual reality for trauma treatment. The analysis also emphasizes the perception of narrative authorship in virtual reality as an essential method for recovering the self-narrative and improving a patient's mental health during self-actualization.