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BACKGROUND: Operating room (OR) nurses experience abuse perpetrated by physicians; however, little research has been conducted to examine nurses' perceptions of the effects of such abuse. AIMS: The aim of this research was to understand participants' perceptions of physician-perpetrated abuse on their health and ability to provide patient care. MATERIALS/METHODS: In this qualitative descriptive study, ten operating room nurses working in Eastern Canada participated in open-ended, individual audiotaped interviews that were transcribed for analysis using Boyatzis' method for code development. RESULTS: Three categories of factors contributing to abuse were developed. The first, culture of the OR, included environment and hierarchy. The second, catalysts of abuse, included nurses' positions and experience as well as non-nurse factors such as resources and interpersonal relationships among physicians. The third category, perceived effects, included psychological, physical and social health consequences for nurses. Effects on patient care consisted of safety and potential challenges to access. DISCUSSION: Nursing practice implications included mentoring, support and accountability for action. Educational implications related to interdisciplinary education and increased education on communication, assertiveness, and awareness of abuse. Implications for research included studying perceptions of other health-care providers including physicians, studying recruitment and retention in relation to abuse, and studying other abuse in health care such as horizontal violence. CONCLUSION: We suggest a proactive approach for empowering OR nurses to address abuse and an increased focus on interdisciplinary roles.

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We present theory and experiment for the task of discriminating two nonorthogonal states, given multiple copies. We implement several local measurement schemes, on both pure states and states mixed by depolarizing noise. We find that schemes which are optimal (or have optimal scaling) without noise perform worse with noise than simply repeating the optimal single-copy measurement. Applying optimal control theory, we derive the globally optimal local measurement strategy, which outperforms all other local schemes, and experimentally implement it for various levels of noise.

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Measurement underpins all quantitative science. A key example is the measurement of optical phase, used in length metrology and many other applications. Advances in precision measurement have consistently led to important scientific discoveries. At the fundamental level, measurement precision is limited by the number N of quantum resources (such as photons) that are used. Standard measurement schemes, using each resource independently, lead to a phase uncertainty that scales as 1/square root N-known as the standard quantum limit. However, it has long been conjectured that it should be possible to achieve a precision limited only by the Heisenberg uncertainty principle, dramatically improving the scaling to 1/N (ref. 3). It is commonly thought that achieving this improvement requires the use of exotic quantum entangled states, such as the NOON state. These states are extremely difficult to generate. Measurement schemes with counted photons or ions have been performed with N < or = 6 (refs 6-15), but few have surpassed the standard quantum limit and none have shown Heisenberg-limited scaling. Here we demonstrate experimentally a Heisenberg-limited phase estimation procedure. We replace entangled input states with multiple applications of the phase shift on unentangled single-photon states. We generalize Kitaev's phase estimation algorithm using adaptive measurement theory to achieve a standard deviation scaling at the Heisenberg limit. For the largest number of resources used (N = 378), we estimate an unknown phase with a variance more than 10 dB below the standard quantum limit; achieving this variance would require more than 4,000 resources using standard interferometry. Our results represent a drastic reduction in the complexity of achieving quantum-enhanced measurement precision.

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Inositol 1,4,5-trisphosphate (IP3) rapidly increased 45Ca2+ efflux from a nonmitochondrial organelle in cultured vascular smooth muscle cells that were permeabilized with saponin. A nucleotide, preferably ATP, was essential for IP3-evoked 45Ca2+ release. Two nonhydrolyzable ATP analogues satisfied the nucleotide requirement for IP3-evoked 45Ca2+ release. IP3 strongly stimulated 45Ca2+ efflux at low temperatures (1 to 15 degrees C). Decreasing the temperature from 37 to 4 degrees C inhibited the rate of IP3-stimulated efflux by only about 33%. The failure of such low temperatures to strongly inhibit IP3-induced 45Ca2+ efflux suggests that IP3 activated a Ca2+ channel, rather than a carrier, by a ligand-binding, rather than a metabolic, reaction.

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