Deciphering Mechanisms for Matrix Stiffness Sensing

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Fragmentation of CD+ induced by intense ultrashort laser pulses

Citation: Graham, L., Zohrabi, M., Gaire, B., Ablikim, U., Jochim, B., Berry, B., . . . Ben-Itzhak, I. (2015). Fragmentation of CD+ induced by intense ultrashort laser pulses. Physical Review A, 91(2), 11. doi:10.1103/PhysRevA.91.023414The fragmentation of CD[superscript +] in intense ultrashort laser pulses was investigated using a coincidence three-dimensional momentum imaging technique improved by employing both transverse and longitudinal electric fields. This allowed clear separation of all fragmentation channels and the determination of the kinetic energy release down to nearly zero, for a molecule with significant mass asymmetry. The most probable dissociation pathways for the two lowest dissociation limits, C[superscript +]+D and C+D[superscript +], were identified for both 22-fs, 798-nm and 50-fs, 392-nm pulses. Curiously, the charge asymmetric dissociation of CD[superscript 2+] was not observed for 392-nm photons, even though it was clearly visible for the fundamental 798 nm at the same peak intensity

The Surgical Infection Society revised guidelines on the management of intra-abdominal infection

Background: Previous evidence-based guidelines on the management of intra-abdominal infection (IAI) were published by the Surgical Infection Society (SIS) in 1992, 2002, and 2010. At the time the most recent guideline was released, the plan was to update the guideline every five years to ensure the timeliness and appropriateness of the recommendations. Methods: Based on the previous guidelines, the task force outlined a number of topics related to the treatment of patients with IAI and then developed key questions on these various topics. All questions were approached using general and specific literature searches, focusing on articles and other information published since 2008. These publications and additional materials published before 2008 were reviewed by the task force as a whole or by individual subgroups as to relevance to individual questions. Recommendations were developed by a process of iterative consensus, with all task force members voting to accept or reject each recommendation. Grading was based on the GRADE (Grades of Recommendation Assessment, Development, and Evaluation) system; the quality of the evidence was graded as high, moderate, or weak, and the strength of the recommendation was graded as strong or weak. Review of the document was performed by members of the SIS who were not on the task force. After responses were made to all critiques, the document was approved as an official guideline of the SIS by the Executive Council. Results: This guideline summarizes the current recommendations developed by the task force on the treatment of patients who have IAI. Evidence-based recommendations have been made regarding risk assessment in individual patients; source control; the timing, selection, and duration of antimicrobial therapy; and suggested approaches to patients who fail initial therapy. Additional recommendations related to the treatment of pediatric patients with IAI have been included. Summary: The current recommendations of the SIS regarding the treatment of patients with IAI are provided in this guideline

Strong-field dissociation dynamics of molecular dications

Citation: Jochim, B., Severt, T., Zohrabi, M., Ablikim, U., Berry, B., Gaire, B., . . . Ben-Itzhak, I. (2015). Strong-field dissociation dynamics of molecular dications. 635(11). doi:10.1088/1742-6596/635/11/112044We focus on the dissociation of metastable molecular dications induced by intense, ultrafast laser pulses. In particular, we demonstrate the dominant role of commonly-neglected permanent-dipole transitions and drive dissociation via a pump-dump-like mechanism within a single laser pulse. © Published under licence by IOP Publishing Ltd

Carrier-envelope phase control over fragmentation of H2 + and D2

Citation: Zohrabi, M., Berry, B., Kling, N. G., Jochim, B., Severt, T., Ablikim, U., . . . Ben-Itzhak, I. (2015). Carrier-envelope phase control over fragmentation of H2 + and D2. 635(11). doi:10.1088/1742-6596/635/11/112045We demonstrate control over fragmentation of H2 + and D2 molecules via the carrier-envelope phase of sub-5 fs laser pulses. Moreover, we attribute our findings to interferences between different pathways involving different net numbers of photons, revealing "high-order" pathways and the importance of the bandwidth. © Published under licence by IOP Publishing Ltd

The importance of Rydberg orbitals in dissociative ionization of small hydrocarbon molecules in intense few-cycle laser pulses

Citation: Jochim, B., Siemering, R., Zohrabi, M., Voznyuk, A., Mahowald, J. B., Schmitz, D. G., . . . De Vivie-Riedle, R. (2015). The importance of Rydberg orbitals in dissociative ionization of small hydrocarbon molecules in intense few-cycle laser pulses. 635(11). doi:10.1088/1742-6596/635/11/112043We demonstrate the importance of ionization from Rydberg orbitals via experimental and theoretical work focusing on the strong-field dissociative single ionization of small hydrocarbons. Our findings suggest that Rydberg states should be routinely considered when studying polyatomic molecules in intense laser fields. © Published under licence by IOP Publishing Ltd.Additional Authors: Wells, E.;De Vivie-Riedle, R

Path Dependence in Decision-Making Processes: Exploring the Impact of Complexity under Increasing Returns

The development of path-dependent processes basically refers to positive feedback in terms of increasing returns as the main driving forces of such processes. Furthermore, path dependence can be affected by context factors, such as different degrees of complexity. Up to now, it has been unclear whether and how different settings of complexity impact path-dependent processes and the probability of lock-in. In this paper we investigate the relationship between environmental complexity and path dependence by means of an experimental study. By focusing on the mode of information load and decision quality in chronological sequences, the study explores the impact of complexity on decision-making processes. The results contribute to both the development of path-dependence theory and a better understanding of decision-making behavior under conditions of positive feedback. Since previous path research has mostly applied qualitative case-study research and (to a minor part) simulations, this paper makes a further contribution by establishing an experimental approach for research on path dependence.You can play an additonal video-file that demonstrates a brief instruction to the ComPad-Explorer (see "Supplementary material" below)