We experimentally demonstrate a source of nearly pure single photons in arbitrary temporal shapes heralded from a parametric down-conversion (PDC) source at telecom wavelengths. The technology is ...enabled by the tailored dispersion of in-house fabricated waveguides with shaped pump pulses to directly generate the PDC photons in on-demand temporal shapes. We generate PDC photons in Hermite-Gauss and frequency-binned modes and confirm a minimum purity of 0.81, even for complex temporal shapes.
Letters to the editor Monroe, Laura B.; Donohue, William A.; Pekow, Charles ...
Society (New Brunswick),
7/1991, Letnik:
28, Številka:
5
Journal Article
Compares 2 samples of mediator intervention strategies to learn about sources of dissatisfaction among clients. Coding of transcripts from family & divorce mediations in Los Angeles, CA, & Marion ...County, IN (total N = 42 cases), indicate that the more mediators ignore disputants' relational concerns, the more difficulty they will experience in reaching agreement. In both samples, couples who came to mediation with significant relational baggage quickly moved the discussion toward these concerns & away from substantive issues. Mediators who had trouble reaching agreement bypassed any mention of these issues & instead focused on facts. By failing to provide the clients with an opportunity to vent emotional concerns, these mediators may have contributed significantly to decreased client satisfaction. 3 Tables, 14 References. Adapted from the source document.
This chapter addresses two long-standing questions concerning ribosome structure and function: (i) How are the mRNA and tRNAs moved through the ribosome following formation of each peptide bond? and ...(ii) how does recognition of a stop codon result in hydrolysis of peptidyl-tRNA? Not surprisingly, results from structural biology have played an important part in formulating mechanistic models for both of these processes. Although structural information is essential for understanding the detailed molecular mechanisms of such processes, it is in itself insufficient for establishing whether or not they are correct. There are already sufficient published examples of false mechanistic inferences based on ribosome structures to remind us that such models need to be tested experimentally, preferably by diverse approaches. Key aspects of the standard models for translocation and termination have emerged from structural observations — cryoEM reconstructions and x-ray crystallography, respectively. Both models have been subjected to experimental tests of various kinds, a process that continues in many laboratories. In the first part of this chapter, we describe the results of experiments using both single-molecule and bulk fluorescence methods to examine the relationship between intersubunit movement, hybrid-states binding of tRNA a6nd translocation. In the second part, we discuss a model for the mechanism of translation termination based on the x-ray crystal structures of the translation termination complexes, and some experimental tests of the model.
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