Wetting films on chemically heterogeneous substrates

Based on a microscopic density functional theory we investigate the morphology of thin liquidlike wetting films adsorbed on substrates endowed with well-defined chemical heterogeneities. As paradigmatic cases we focus on a single chemical step and on a single stripe. In view of applications in microfluidics the accuracy of guiding liquids by chemical microchannels is discussed. Finally we give a general prescription of how to investigate theoretically the wetting properties of substrates with arbitrary chemical structures.Comment: 56 pages, RevTeX, 20 Figure

Unconventional Low-Cost Fabrication and Patterning Techniques for Point of Care Diagnostics

The potential of rapid, quantitative, and sensitive diagnosis has led to many innovative ‘lab on chip’ technologies for point of care diagnostic applications. Because these chips must be designed within strict cost constraints to be widely deployable, recent research in this area has produced extremely novel non-conventional micro- and nano-fabrication innovations. These advances can be leveraged for other biological assays as well, including for custom assay development and academic prototyping. The technologies reviewed here leverage extremely low-cost substrates and easily adoptable ways to pattern both structural and biological materials at high resolution in unprecedented ways. These new approaches offer the promise of more rapid prototyping with less investment in capital equipment as well as greater flexibility in design. Though still in their infancy, these technologies hold potential to improve upon the resolution, sensitivity, flexibility, and cost-savings over more traditional approaches

Strategies for Controlled Placement of Nanoscale Building Blocks

The capability of placing individual nanoscale building blocks on exact substrate locations in a controlled manner is one of the key requirements to realize future electronic, optical, and magnetic devices and sensors that are composed of such blocks. This article reviews some important advances in the strategies for controlled placement of nanoscale building blocks. In particular, we will overview template assisted placement that utilizes physical, molecular, or electrostatic templates, DNA-programmed assembly, placement using dielectrophoresis, approaches for non-close-packed assembly of spherical particles, and recent development of focused placement schemes including electrostatic funneling, focused placement via molecular gradient patterns, electrodynamic focusing of charged aerosols, and others

Cosmic ray oriented performance studies for the JEM-EUSO first level trigger

JEM-EUSO is a space mission designed to investigate Ultra-High Energy Cosmic Rays and Neutrinos (E > 5 ⋅ 1019 eV) from the International Space Station (ISS). Looking down from above its wide angle telescope is able to observe their air showers and collect such data from a very wide area. Highly specific trigger algorithms are needed to drastically reduce the data load in the presence of both atmospheric and human activity related background light, yet retain the rare cosmic ray events recorded in the telescope. We report the performance in offline testing of the first level trigger algorithm on data from JEM-EUSO prototypes and laboratory measurements observing different light sources: data taken during a high altitude balloon flight over Canada, laser pulses observed from the ground traversing the real atmosphere, and model landscapes reproducing realistic aspect ratios and light conditions as would be seen from the ISS itself. The first level trigger logic successfully kept the trigger rate within the permissible bounds when challenged with artificially produced as well as naturally encountered night sky background fluctuations and while retaining events with general air-shower characteristics

Implementing a global perspective: the role of teacher-librarians in facilitating curriculum change

The politics of education is such that curricula in our schools are continually changing. In British Columbia, this is especially apparent since the Sullivan Royal Commission on Education released its report in August 1988. The Commission suggested that "a quality curriculum clearly reflects relevance, equity of access, response to diversity, accountability, and achievement" (Sullivan, 1988, p. 79). Consequently, the British Columbia Ministry of Education published several documents to guide teachers in developing, implementing, and assessing curricula, which promotes the development of an educated citizen. As a teacher and a teacher-librarian, I believe that it is my responsibility to help develop students as educated citizens. I also believe that to become educated citizens, students need to develop a global perspective. The purpose of this research was to investigate ways in which teacher-librarians could facilitate the implementation of a global perspective. I expected to gain insight into the ways that reflection and collaboration motivated teacher-librarians to affect curriculum development and implementation. I also expected to create a situation that encouraged teacher-librarians to evolve as leaders in their schools, whether it was as cooperative program planners and teachers, as advocates of teaching for a global perspective, or as forerunners of information technology. My method of investigation was action research. I chose this approach because it was a collaborative process that involved creating a research plan, acting on the plan, reflecting on the information that was collected, and then revising the plan. Furthermore, it allowed for the improvement of our practice as we progressed. During the project, a group of five teacher-librarians, including me, completed two action research cycles where we developed and reflected upon strategies for implementing a global perspective within our separate schools. In conclusion, the teacher-librarians demonstrated a commitment to the project and documented various situations in which they influenced curriculum implementation that reflected facilitating a global perspective. They felt that the action research process provided valuable opportunities for sharing with peers, which generally does not occur because teacher-librarians tend to occupy unique, solitary positions within their schools.Education, Faculty ofCurriculum and Pedagogy (EDCP), Department ofGraduat

EFFECTS OF RAIL STATIONS AT AIRPORTS IN EUROPE

The effects of rail stations, including high-speed rail, at airports in Europe are discussed in terms of a cost-benefit framework. Rail stations are operational at many European airports and are at the center of interest when road access relief at airports is considered, as well as when rail and air transport complementarity is considered. As public budget deficits are under more scrutiny than in the past and privatization of state-owned public transport companies is being considered, it is of interest to know the extent to which rail stations at airports improve the performance of the rail companies and have a positive impact on the economy as a whole (are of value to taxpayers). The study is based on a cost-benefit analysis of rail stations at five major airports (Brussels, Zurich, Frankfurt, Paris-Orly, and Paris-Charles de Gaulle) and two medium-sized airports (Geneva and Stuttgart). The results of case studies of several rail stations (those in Belgium, France, Germany, and Switzerland), which had wide spectra of technology and operating system backgrounds, showed that the overall effects of rail stations, by taking into account investment costs and the partial effects on the railways, were positive for the major (hub) airports analyzed [except in particular cases for particular reasons (Brussels and Paris-Orly)] but were balanced or negative for the medium-sized airports analyzed. The results show not only the impact of airport size but also that of distance to the airport by rail, because the benefit to users in terms of time and fare savings played a significant role and highlighted the benefits of having access to a rail network as much as possible. Finally, the effects on public transport as a whole (i.e., the effects on all public transport companies at the airport, including taxi and parking operators) were negative

Combined crystal structure prediction and high-pressure crystallization in rational pharmaceutical polymorph screening.

Organic molecules, such as pharmaceuticals, agro-chemicals and pigments, frequently form several crystal polymorphs with different physicochemical properties. Finding polymorphs has long been a purely experimental game of trial-and-error. Here we utilize in silico polymorph screening in combination with rationally planned crystallization experiments to study the polymorphism of the pharmaceutical compound Dalcetrapib, with 10 torsional degrees of freedom one of the most flexible molecules ever studied computationally. The experimental crystal polymorphs are found at the bottom of the calculated lattice energy landscape, and two predicted structures are identified as candidates for a missing, thermodynamically more stable polymorph. Pressure-dependent stability calculations suggested high pressure as a means to bring these polymorphs into existence. Subsequently, one of them could indeed be crystallized in the 0.02 to 0.50 GPa pressure range and was found to be metastable at ambient pressure, effectively derisking the appearance of a more stable polymorph during late-stage development of Dalcetrapib