Publications by authors named "J Cedar Farwell"

Purpose: In mono-isocentric radiation therapy treatment plans designed to treat the whole breast and supraclavicular lymph nodes, the fields meet at isocenter, forming the match line. Insufficient coverage at the match line can lead to recurrence, and overlap over weeks of treatment can lead to increased risk of healthy tissue toxicity. Cherenkov imaging was used to assess the accuracy of delivery at the match line and identify potential incidents during patient treatments.

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In this study the metric of detective quantum efficiency (DQE) was applied to Cherenkov imaging systems for the first time, and results were compared for different detector hardware, gain levels and with imaging processing for noise suppression. Intensified complementary metal oxide semiconductor cameras using different image intensifier designs (Gen3 and Gen2+) were used to image Cherenkov emission from a tissue phantom in order to measure the modulation transfer function (MTF) and noise power spectrum (NPS) of the systems. These parameters were used to calculate the DQE for varying acquisition settings and image processing steps.

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In light of the recent events of terrorism and publicized cases of mass slayings and serial killings, there have been calls from the public and policy-makers alike for neuroscience and neurotechnology (neuroS/T) to be employed to intervene in ways that define and assess, if not prevent, such wanton acts of aggression and violence. Ongoing advancements in assessment neuroS/T have enabled heretofore unparalleled capabilities to evaluate the structure and function of the brain, yet each and all are constrained by certain technical and practical limitations. In this paper, we present an overview of the capabilities and constraints of current assessment neuroS/T, address neuro-ethical and legal issues fostered by the use and potential misuse of these approaches, and discuss how neuroethics may inform science and the law to guide right and sound applications of neuroS/T to "deliver us from evil" while not being led into temptations of ampliative claims and inapt use.

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Purpose: To evaluate the radiation doses delivered during volumetric helical perfusion CT of the thorax, abdomen or pelvis.

Materials And Methods: The dose-length product (DLP) and CT dose index (CTDIvol) were recorded and effective dose (E) determined for patients undergoing CT (4D adaptive spiral) for tumour evaluation. Image noise and contrast to noise (CNR) at peak enhancement were also assessed for quality.

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The tetracyclic dilithio-Si,Si'-oxo-bridged bis(N,N'-methylsilyl-beta-diketiminates) 2 and 3, having an outer LiNCCCNLiNCCCN macrocycle, were prepared from [Li{CH(SiMe(3))SiMe(OMe)(2)}](infinity) and 2 PhCN. They differ in that the substituent at the beta-C atom of each diketiminato ligand is either SiMe(3) (2) or H (3). Each of and has (i) a central Si-O-Si unit, (ii) an Si(Me) fragment N,N'-intramolecularly bridging each beta-diketiminate, and (iii) an Li(thf)(2) moiety N,N'-intermolecularly bridging the two beta-diketiminates (thf = tetrahydrofuran).

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