Applying persuasive design in a diabetes mellitus application

This paper describes persuasive design methods and compares this to an application currently under development for diabetes mellitus patients. Various elements of persuasion and a categorization of persuasion types are mentioned. Also discussed are principles of how successful persuasion should be designed, as well as the practical applications and ethics of persuasive design. This paper is not striving for completeness of theories on the topic, but uses the theories to compare it to an application intended for diabetes mellitus patients. The results of this comparison can be used for improvements of the application

It's Time for Summer: An Analysis of Recent Policy and Funding Opportunities

Recommends ways to improve and expand summer learning programs by better coordinating federal, state and local programs, including ensuring that federal program regulations explicitly allow spending for summer programs and creating funding collaboratives

Optical fibres : analysis, numerical modelling and optimisation

For several decades silica-based optical fibres have been used for telecommunication and sensor purposes. The single-mode fibre is frequently employed in long-distance networks, whereas the multi-mode fibre is the preferred means of signal transport in campus and in-building networks. Because of the huge bandwidth of optical fibres in comparison to its electrical wireless and copper-based counterparts, the demand for optical fibres keeps increasing. In a competitive market, fibre manufacturers aim to produce ever better fibres that are as cheap and easy to employ as possible. As fibre research, development and manufacturing is a mature discipline, improvements in fibre design can only be achieved through the construction of robust, accurate and efficient numerical fibre models for the computation of those quantities that determine the behaviour of the fibre. We have developed a modular software code, based on Maxwell’s equations, to compute these quantities in a vectorial full-wave way for both single-mode and multi-mode optical fibres. Key is the refractive-index profile, or, more specifically, the dopant profile, as it defines the propagation, splicing and bending-loss characteristics of the fibre. For the single-mode fibre, the fibre quantities that we have concentrated on are dispersion, dispersion slope, mode-field diameter, effective area, bending loss, effective and theoretical cut-off wavelength and MAC-value. We highlight one fibre quantity in particular, viz. the computation of the bending loss in a single-mode fibre. Many approximate modelling techniques have been developed to estimate this loss in a fast way. Our numerical scheme, however, is the first rigorous one, as we have performed a vectorial full-wave analysis of the bent optical fibre. In this context, triple integrals involving products of Bessel functions with large, complex order and argument appear. Due to cancellations in the pertaining computation, a high relative accuracy is needed for the computation of each product. As a result, it takes weeks on a contemporary computer to compute the bending loss as a function of the radius of curvature. We have used the vectorial full-wave bending-loss results to determine the most appropriate approximate method. Subsequently, we have extended that approximate method to compute the bending losses of higher-order modes, since the required effective cut-off wavelength depends on the bending loss of the first higher-order mode. The selected approximate method has been used in the ensuing bending-loss calculations. Since the fibre properties are often conflicting, it is a challenging task to adapt the radial dopant profile to meet a set of predefined design goals. A design goal is a combination of desired values for (some of) the aforementioned fibre quantities, and can mathematically be translated into a cost function. The minimisation of this cost function provides us with the optimal dopant profile for that specific set. For the single-mode fibre, we have performed this minimisation for piecewise-linear profiles, by employing various global and gradient-based local optimisation strategies to speed up the design step considerably. Frequently,these optimisation strategies lead to counter-intuitive dopant profile designs that could not have been contrived otherwise. We have selected a deliberate mix of several optimisation routines and have compared their performances. Perhaps the most important conclusion is that there still appears to be room for improvement in the design of the radial dopant profile of commercially available fibres. For the multi-mode fibre, vectorial full-wave optimisation is not feasible yet because of the long computation times for the large number of propagating modes. Still, our numerical scheme allows for a manual fine-tuning of the popular power-law profile to minimise differential mode delay. Further, we have included mode coupling and differential mode attenuation in our model to obtain intensity patterns that match closely with measurements. We have also analysed the influence of profile variations, e.g. on-axis dips and kinks, on the intensity pattern. A selective excitation of different mode groups in a multi-mode fibre, offers the possibility to create several independent transmission channels, and thus a higher information capacity. Recently, the feasibility of this so-called mode group diversity multiplexing technique has been demonstrated. Simulations provide us with a means to better understand its operation and possibly increase its efficiency. The channel separation may be enhanced by employing a lens between the fibre and the detector, which is called mode-selective spatial filtering. Our numerical simulations of a mode group diversity multiplexing link, with and without mode-selective spatial filtering, are in agreement with the measurements. The above discussion makes clear that the developed software code has a wide range of applicability. Moreover, it is built in a modular way and thus extensions, like the inclusion of more fibre quantities or different profile dopants, are straightforward

Proteomic analysis of outer membrane vesicles of Aeromonas hydrophila ML09-119

Aeromonas hydrophila ML09-119 is an important fish pathogen that severely affects channel catfish aquaculture. To better understand this strain’s virulence factors, outer membrane vesicles (OMVs) were isolated, and their proteome was assessed. Using transmission electron microscopy and dynamic light scattering, OMVs were shown to be monodispersed particles with an average diameter of 120.33 nm. OMV proteins were identified using mass spectrometry, and analysis of the resulting proteome of 74 proteins revealed that many originated from the cytoplasm, but there was an enrichment of outer membrane, periplasmic, and extracellular proteins compared to the total proteome. The majority of the functional classifications were associated with bacterial metabolism. Of the predicted virulence factors, several had a putative function in adherence, and there were type III secretions system proteins as well as three secreted exotoxins. Overall, our data reveal new insights into A. hydrophila OMVs and their potential roles in physiology and virulence

Manifold field effects at a complex oxide interface

The fundamental physical process underlying all consumer electronics on the market today is the (electric-)field effect. In the broadest sense of the word, it encompasses tuning the properties of a material by an electric field, which is usually done by externally applying a voltage. The elementary electronic building block, the field-effect transistor, nowadays comes by the billions on the size of a postage stamp, and is conventionally based on the material silicon. Replacing silicon by a different material may lead to electronic devices with novel functionality, such as devices that compute more efficiently or in a different way: for example, future devices may closely resemble the way nature 'computes' interactions between atoms and molecules; the realization of such devices is projected to enable breakthroughs in medical and material sciences. In this light, the conducting interface between lanthanum aluminate (LaAlO3) and strontium titanate (SrTiO3) is especially appealing: it exhibits exotic phenomena like superconductivity and magnetism, which are highly tunable by an externally applied voltage. These unique characteristics make this interface a promising platform for better understanding these phenomena on a fundamental level, as well as for creating new electronic devices for innovative computing methods. The main result of this thesis is that the field effect at the LaAlO3 - SrTiO3 interface goes beyond accumulating and depleting charges in a channel. Correlated-electron phenomena such as superconductivity and magnetism are deeply connected to the electronic band structure; the magnetotransport studies described in this thesis show that an externally applied gate voltage can change the band structure of this interface; a direct manifestation of the Schrödinger equation, this premier result establishes electrostatic control over the fundamental electronic properties of a material. The following chapters show that this evolution of the band structure with gate voltage is closely related to tuning superconductivity in this system, and that the electrostatic confinement is the main factor distinguishing bulk and surface states. Finally, the limits of complex-oxide field-effect devices are explored in terms of electric field strength, dielectric layer thickness, and lateral dimensions. In general, this thesis contributes both to the fundamental understanding of the field effect in advanced materials, and to the boundary conditions of using such materials in functional devices

A new traversal method for virtual reality: overcoming the drawbacks of common methods

One of the biggest issues facing VR as a platform is the limitation of the user’s physical space. Not everyone has a lab, empty warehouse, or open space in their home or office, and even if they do, the hardware also limits the physical space the user can take advantage of. Fitting the entirety of the environment within few square meters is a strict limitation for many applications. A method of moving the user within a larger space is needed, but current methods come with drawbacks. Developing a new movement method that avoids these drawbacks will help ensure a better experience for the user