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Intervention et animation de la séance n°3 du séminaire "Kracauer et les miniatures urbaines : une écriture sensible critique" dirigé par Rachel Thomas.; National audience

The appropriate representation of the photomask in the simulation of wafer lithography processes has been shown to be of vital importance for 14-nm and below [1]. This task is difficult, since accurate optical metrology and physical metrology of the three-dimensional mask structure is not always available. OPC models for wafer patterning comprise representations of the mask, the optics, and the photoresist process. The traditional calibration of these models has involved empirical tuning of model parameters to CD-SEM data from printed photoresist patterns. Such a flow necessarily convolves the resist effects and it has been difficult to reliably obtain mask and optical parameters which are most representative of physical reality due to aliasing effects. In this work, we have undertaken to decouple the mask model from the photoresist process by use of the ZEISS Wafer-Level CD (WLCD) tool based upon aerial image metrology. By measuring the OPC test pattern mask with WLCD, the mask parameters in the OPC model can be tuned directly without interference of resist effects. This work utilized 14-nm,10-nm, and 7-nm node masks, and we demonstrate that the use of such a flow leads to the most predictive overall OPC models, and that the mask parameters resulting from this flow more closely match the expected physical values. More specifically, the mask corner rounding, sidewall angle, and bias values were tuned to the WLCD data instead of the wafer CD SEM data, and resulted in improved predictive capability of the model. Furthermore, other mask variables not traditionally tuned can be verified or tuned by matching simulation to aerial image metrology.

The development of professional attitudes and behaviors in students who will become pharmacists is an important outcome for pharmacy education. The literature in higher education has shown that student engagement during college leads to positive learning outcomes as well as the development of character. Assuming that character development and professionalism development are parallel processes, this preliminary research seeks to describe first-year experience (FYE) programming and health professional schools' programming intended to promote professional behavior. Objectives (1) To compare strategies used by undergraduate FYE programs to enhance student engagement with approaches used by professional doctoral programs to improve professionalism; and (2) to recommend methods of improving development of professionalism in pharmacy education. Methods Interviews were conducted with FYE leaders and professional school leaders in six US universities that have pharmacy schools. An analysis of the literature in higher education on student engagement and FYE was conducted. Results Both FYE and professional programs used orientation programs, course work, and student codes of conduct to develop character or professionalism, respectively. The FYE programs included more reflective/writing activities, peer mentoring, and diversity activities than professional schools. Conclusions The undergraduate FYE is a useful framework for developing professional attitudes and behaviors in pharmacy students. Recommendations for pharmacy education include: (1) incorporating professionalism development into program mission statements; (2) communicating the importance of developing professionalism to students; (3) offering activities aimed at professional development; and (4) engaging students fully in these activities.

Here we investigate the dynamics of a gas bubble rising through an inclined channel in two dimensions. The fluids obey the Stokes equations and a boundary integral method is used to solve for the dynamics of the bubbles. Bubbles with and without an insoluble surfactant are considered. We study the dynamics of the bubbles as a function of the angle of inclination, the Bond number, and the other physical parameters of the problem. We find that for large enough Bond numbers a thread of liquid is formed on the bubble interface. We also find that for large enough angles of inclination, it is possible for the bubble to bounce along the top wall of the channel. Our computations are consistent with recent experimental results.

An experimental investigation into the changes in turbulence structure of the boundary layer over a wall oscillating in spanwise direction was carried out in a wind tunnel using hot-wire anemometry and flow visualisation. The main purpose of this investigation is to confirm recent numerical results which seem to indicate that the turbulent skinfriction drag can be reduced by up to 40 percent over the oscillating wall. The results from the present investigation clearly indicate that the logarithmic velocity profiles are shifted upwards and turbulence intensities reduced by the spanwise-wall oscillation, confirming the basic conclusions of recent direct numerical simulation. Also, the skinfriction reductions as much as 45% are observed in the present experiment at an optimum speed of wall oscillation. The flow-visualisation study indicates that the longitudinal vortices in the near-wall region of the boundary layer are twisted towards the direction of spanwise-wall motion with oscillation. As a result, the vortices are realigned into the cross-flow direction, resulting in a reduction of turbulent wall-skin friction by spanwise-wall oscillation. A conceptual model for a turbulent boundary layer over an oscillating wall is proposed to examine the mechanism of turbulent drag reduction by spanwise-wall oscillation.

Several compressible mixing layers, with one supersonic and one subsonic streams, are experimentally analyzed by pressure measurements and laser anemometry. Detailed measurements of the mean and fluctuating velocity fields are provided and compared against data from incompressible flows. The effects of compressibility on the flows are observed. The spreading rate of the mixing layers decrease when the Mach number is increased, in good agreement with results found in the literature. Laser Doppler measurements are performed for three test cases. The compressibility effects on the fluctuation levels are discussed and compared with existing results. The evolution of the turbulence structure of the flow, when the convective Mach number increases, is considered in the analysis when separate LDA seeding regimens are employed on the two sides of the layers. Some modifications of the large scale organization are observed when supersonic and subsonic mixing layers are compared and the two sides of the supersonic mixing layers have different characteristics.

An electronic airport moving map is standard on today's aircraft, starting with the Airport Moving Map (AMM) on the Electronic Flight Bag (EFB) of the Boeing 777. Airbus followed with the Onboard Airport Navigation System (OANS) on the navigation display of the A380, and Boeing with integrated Airport Map with the navigation display on the 787 and 747–8. One of the next steps for AMM displays will be the display of assigned taxi routes. Input, management, and display of taxi routes in the cockpit have been covered in various studies in the past. However, regular use is not possible yet as Aerodrome Mapping Databases (AMDB) as specified in the industry standards RTCA DO-272 (User Requirements)[1], DO-291 (Exchange Format)[2], and ARINC 816 (Embedded Format)[3] do not contain the required connectivity information. The joint RTCA special committee SC-217 / EUROCAE WG-44 worked on this issue over the past two years and updated data requirements, data model, and capture rules accordingly. The approach was driven by various depiction concepts (highly-detailed vs. generalized) and taxi route input methods (i.e., SC-214 D-TAXI data links), but also data availability and the characteristics of taxi instructions from official sources (i.e., airport facility directives and the Notices to Airmen Publication). The result is a graph network with nodes and edges modeling taxiway and runway connectivities within an airport, called the Aerodrome Surface Routing Network (ASRN). Intersections are modeled by nodes of the graph. Other node types are used for holding positions or parking positions. Feasible connections between two nodes are modeled by edges of the graph. This paper provides an overview of the new elements of RTCA DO-272C and DO-291B and in particular about the specifications for the ASRN. The new standard documents (DO-272C/DO-291B) are scheduled for publication by end of 2011.

This review presents an interesting new analysis of cyclo-oxygenase-2 (COX-2) inhibitor safety, concluding that long-term use results in more serious adverse events than traditional nonsteroidal anti-inflammatory drugs (NSAIDs). The nonsystematic and retrospective properties of this analysis limit its validity. However, the fact that an evaluation of long-term data found some small harm to COX-2 inhibitors relative to traditional NSAIDs (number needed to harm=78 over 9 months) should give clinicians pause. Until better meta-analyses or new safety data are published, clinicians should prescribe COX-2 inhibitors long-term only for those patients deemed to be at high risk of ulcer complications.

Inhaled anticholinergic drugs are considered one of the principal bronchodilator treatments for chronic obstructive pulmonary disease (COPD). Ipratropium bromide is an anticholinergic drug frequently administered for the treatment of COPD. Unfortunately, ipratropium has a short duration of action, requiring administration every 6 hours; this regimen affects adherence to drug therapy. Tiotropium bromide is structurally similar to ipratropium and is under development in the United States. The duration of action of tiotropium is approximately 24 hours, allowing for once-daily dosing. Other than xerostomia being more common with tiotropium than with ipratropium, the safety profiles of these drugs were similar in studied populations. On the basis of its improvements in trough spirometric measurements and improved pharmacokinetic profile compared with that of ipratropium, tiotropium is likely to become the first-line anticholinergic agent in the treatment of patients with COPD.

Experiments are discussed in an adverse pressure gradient boundary layer, which develops on a flat plate in a windtunnel. The skin friction is measured with a drag balance and velocity profiles are measured with a hot-wire. The measured velocity profiles deviate from the standard logarithmic profile valid for the zero pressure gradient case.