Simultaneous visible and near-infrared spectrophotometry of Comet Austin 1989c

Simultaneous visible and near-infrared spectra of Comet Austin were obtained wit the 1.5 m and 2.3 m telescopes of the University of Arizona Observatories on 1990 May 16. The visible spectrum obtained with the IHW spectrograph covers the 3126-9490 A wavelength interval, while the near-infrared spectrum obtained with the germanium spectrometer covers the 9036-12794 A wavelength interval. Simultaneous measurements of integrated band fluxes are presented for the CN B 2Sigma(+) - X 2Sigma(+) (violet) and A 2Pi - X 2Sigma(+) (red) systems. A CN spectrum and CN band flux ratios calculated from a fluoresence equilibrium model are also presented. From a comparison between the observed and calculated CN spectra and band flux ratios, it is found that red system oscillator strengths determined from recent ab initio calculations appropriately describe the radiative properties of CN molecules

The effects of fatigue on robotic surgical skill training in Urology residents

This study reports on the effect of fatigue on Urology residents using the daVinci surgical skills simulator (dVSS). Seven Urology residents performed a series of selected exercises on the dVSS while pre-call and post-call. Prior to dVSS performance a survey of subjective fatigue was taken and residents were tested with the Epworth Sleepiness Scale (ESS). Using the metrics available in the dVSS software, the performance of each resident was evaluated. The Urology residents slept an average of 4.07 h (range 2.5-6 h) while on call compared to an average of 5.43 h while not on call (range 3-7 h, p = 0.08). Post-call residents were significantly more likely to be identified as fatigued by the Epworth Sleepiness Score than pre-call residents (p = 0.01). Significant differences were observed in fatigued residents performing the exercises, Tubes and Match Board 2 (p = 0.05, 0.02). Additionally, there were significant differences in the total number of critical errors during the training session (9.29 vs. 3.14, p = 0.04). Fatigue in post-call Urology residents leads to poorer performance on the dVSS simulator. The dVSS may become a useful instrument in the education of fatigued residents and a tool to identify fatigue in trainees

Antenna reconfiguration verification and validation

A method of testing the electrical functionality of an optically controlled switch in a reconfigurable antenna is provided. The method includes configuring one or more conductive paths between one or more feed points and one or more test point with switches in the reconfigurable antenna. Applying one or more test signals to the one or more feed points. Monitoring the one or more test points in response to the one or more test signals and determining the functionality of the switch based upon the monitoring of the one or more test points

Computer memories: the history of computer form

This paper looks at the computer as a truly global form. The similar beige boxes found in offices across the world are analysed from the perspective of design history rather than that of the history of science and technology. Through the exploration of an archive of computer manufacturer's catalogues and concurrent design texts, this paper examines the changes that have occurred in the production and consumption of the computer in the context of the workplace, from its inception as a room-sized mainframe operated through a console of flashing lights, to the personal computer as a 'universal' form, reproduced by many manufacturers. It shows how the computer in the past has been as diverse as any other product, and asks how and why it now appears as a standardised, sanitised object. In doing so our relationship with the office computer, past and present is explored, revealing a complex history of vicissitude.</p

Craniux: A LabVIEW-Based Modular Software Framework for Brain-Machine Interface Research

This paper presents “Craniux,” an open-access, open-source software framework for brain-machine interface (BMI) research. Developed in LabVIEW, a high-level graphical programming environment, Craniux offers both out-of-the-box functionality and a modular BMI software framework that is easily extendable. Specifically, it allows researchers to take advantage of multiple features inherent to the LabVIEW environment for on-the-fly data visualization, parallel processing, multithreading, and data saving. This paper introduces the basic features and system architecture of Craniux and describes the validation of the system under real-time BMI operation using simulated and real electrocorticographic (ECoG) signals. Our results indicate that Craniux is able to operate consistently in real time, enabling a seamless work flow to achieve brain control of cursor movement. The Craniux software framework is made available to the scientific research community to provide a LabVIEW-based BMI software platform for future BMI research and development

An Efficient Protocol for the Palladium-Catalyzed Asymmetric Decarboxylative Allylic Alkylation Using Low Palladium Concentrations and a Palladium(II) Precatalyst

Enantioselective catalytic allylic alkylation for the synthesis of 2-alkyl-2-allylcycloalkanones and 3,3-disubstituted pyrrolidinones, piperidinones and piperazinones has been previously reported by our laboratory. The efficient construction of chiral all-carbon quaternary centers by allylic alkylation was previously achieved with a catalyst derived in situ from zero-valent palladium sources and chiral phosphinooxazoline (PHOX) ligands. We now report an improved reaction protocol with broad applicability among different substrate classes in industry-compatible reaction media using loadings of palladium(II) acetate as low as 0.075 mol% and the readily available chiral PHOX ligands. The novel and highly efficient procedure enables facile scale-up of the reaction in an economical and sustainable fashion

Towards an understanding of tensile deformation in Ti-based bulk metallic glass matrix composites with BCC dendrites

The microstructure and tension ductility of a series of Ti-based bulk metallic glass matrix composite (BMGMC) is investigated by changing content of the β stabilizing element vanadium while holding the volume fraction of dendritic phase constant. The ability to change only one variable in these novel composites has previously been difficult, leading to uninvestigated areas regarding how composition affects properties. It is shown that the tension ductility can range from near zero percent to over ten percent simply by changing the amount of vanadium in the dendritic phase. This approach may prove useful for the future development of these alloys, which have largely been developed experimentally using trial and error