WRISTBAND.IO:expanding input and output spaces of a Smartwatch

Smartwatches are characterized by their small size designed for wearability, discretion, and mobile interactions. Most of the interactivity, however, is limited to the size of the display, introducing issues such as screen occlusion and limited information density. We introduce Wristband.io, a smartwatch with an extended interaction space along the wristband, enabling (i) back-of-band interaction using a touchpad, (ii) a low resolution ambient watchband display for offscreen notification, and (iii) tangible buttons for quick, eyes-free input. Insights gained through a study show that back-of-band input increases accuracy and task completion rates for smaller on-screen targets. We probe the design space of Wristband.io with three applications

WRISTBAND.IO:expanding input and output spaces of a Smartwatch

Smartwatches are characterized by their small size designed for wearability, discretion, and mobile interactions. Most of the interactivity, however, is limited to the size of the display, introducing issues such as screen occlusion and limited information density. We introduce Wristband.io, a smartwatch with an extended interaction space along the wristband, enabling (i) back-of-band interaction using a touchpad, (ii) a low resolution ambient watchband display for offscreen notification, and (iii) tangible buttons for quick, eyes-free input. Insights gained through a study show that back-of-band input increases accuracy and task completion rates for smaller on-screen targets. We probe the design space of Wristband.io with three applications

CurationSpace:Cross-Device Content Curation Using Instrumental Interaction

For digital content curation of historical artefacts, curators collaboratively collect, analyze and edit documents, images, and other digital resources in order to display and share new representations of that information to an audience. Despite their increasing reliance on digital documents and tools, current technologies provide little support for these specific collaborative content curation activities. We introduce CurationSpace - a novel cross-device system - to provide more expressive tools for curating and composing digital historical artefacts. Based on the concept of Instrumental Interaction, CurationSpace allows users to interact with digital curation artefacts on shared interactive surfaces using personal smartwatches as selectors for instruments or modifiers (applied to either the whole curation space, individual documents, or fragments). We introduce a range of novel interaction techniques that allow individuals or groups of curators to more easily create, navigate and share resources during content curation. We report insights from our user study about people's use of instruments and modifiers for curation activities

On the decisional Diffie-Hellman problem for class group actions on oriented elliptic curves

We show how the Weil pairing can be used to evaluate the assigned characters of an imaginary quadratic order $\mathcal{O}$ in an unknown ideal class $[\mathfrak{a}] \in \mathrm{Cl}(\mathcal{O})$ that connects two given $\mathcal{O}$-oriented elliptic curves $(E, \iota)$ and $(E', \iota') = [\mathfrak{a}](E, \iota)$. When specialized to ordinary elliptic curves over finite fields, our method is conceptually simpler and often somewhat faster than a recent approach due to Castryck, Sot\'akov\'a and Vercauteren, who rely on the Tate pairing instead. The main implication of our work is that it breaks the decisional Diffie-Hellman problem for practically all oriented elliptic curves that are acted upon by an even-order class group. It can also be used to better handle the worst cases in Wesolowski's recent reduction from the vectorization problem for oriented elliptic curves to the endomorphism ring problem, leading to a method that always works in sub-exponential time.Comment: 18 p

Multilevel analysis of nuclear dynamics in lamin perturbed fibroblasts

The nuclear lamina provides structural support to the nucleus and has a central role in defining nuclear organization. Defects in its filamentous constituents, the lamins, lead to a class of diseases collectively referred to as laminopathies. On the cellular level, lamin mutations affect the physical integrity of nuclei and nucleo-cytoskeletal interactions, resulting in increased susceptibility to mechanical stress and altered gene expression [1]. Most studies regarding the mechanical properties of the nucleus in laminopathic conditions are based on the induction of extracellular stress, such as strain or compression, and focus on nuclear integrity and/or nucleo-cytoskeletal interaction [2]. Far less is known about the role of nuclear organization and mobility under basal steady-state conditions. In this study, we quantitatively compared nuclear organization, nuclear deformation and chromatin mobility of fibroblasts from a Hutchinson-Gilford progeria patient with cells from a lamin A/C-deficient patient and wild-type dermal fibroblasts. To this end, we created a toolbox in imageJ for automatically analyzing both nuclear as well as subnuclear dynamics in living cells. Simultaneously, we developed a workflow for comparing cellular morphology and subcellular protein distribution in a high content fashion. We found that the absence of functional lamin A/C leads to increased nuclear plasticity on the hour and minute time scale but also to increased intranuclear mobility down to the seconds time scale. In contrast, progeria cells showed overall reduced nuclear dynamics. In addition, high content analysis revealed marked morphological and topological differences between different culture passages within a cell type and between different pathological variants of culture-age matched laminopathic cell types

Horizontal racewalking using radical isogenies

We address three main open problems concerning the use of radical isogenies, as presented by Castryck, Decru and Vercauteren at Asiacrypt 2020, in the computation of long chains of isogenies of fixed, small degree between elliptic curves over finite fields. Firstly, we present an interpolation method for finding radical isogeny formulae in a given degree $N$, which by-passes the need for factoring division polynomials over large function fields. Using this method, we are able to push the range for which we have formulae at our disposal from $N \leq 13$ to $N \leq 37$ (where in the range $18 \leq N \leq 37$ we have restricted our attention to prime powers). Secondly, using a combination of known techniques and ad-hoc manipulations, we derive optimized versions of these formulae for $N \leq 19$, with some instances performing more than twice as fast as their counterparts from 2020. Thirdly, we solve the problem of understanding the correct choice of radical when walking along the surface between supersingular elliptic curves over $\mathbb{F}_p$ with $p \equiv 7 \bmod 8$; this is non-trivial for even $N$ and was settled for $N = 2$ and $N = 4$ only, in the latter case by Onuki and Moriya at PKC 2022. We give a conjectural statement for all even $N$ and prove it for $N \leq 14$. The speed-ups obtained from these techniques are substantial: using $16$-isogenies, the computation of long chains of $2$-isogenies over $512$-bit prime fields can be accelerated by a factor $3$, and the previous implementation of CSIDH using radical isogenies can be sped up by about $12\%$

Investigating the Role of an Overview Device in Multi-Device Collaboration

The availability of mobile device ecologies enables new types of ad-hoc co-located decision-making and sensemaking practices in which people find, collect, discuss, and share information. However, little is known about what kind of device configurations are suitable for these types of tasks. This paper contributes new insights into how people use configurations of devices for one representative example task: collaborative co-located trip-planning. We present an empirical study that explores and compares three strategies to use multiple devices: no-overview, overview on own device, and a separate overview device. The results show that the overview facilitated decision- and sensemaking during a collaborative trip-planning task by aiding groups to iterate their itinerary, organize locations and timings efficiently, and discover new insights. Groups shared and discussed more opinions, resulting in more democratic decision-making. Groups provided with a separate overview device engaged more frequently and spent more time in closely-coupled collaboration

EagleView:A Video Analysis Tool for Visualising and Querying Spatial Interactions of People and Devices

To study and understand group collaborations involving multiple handheld devices and large interactive displays, researchers frequently analyse video recordings of interaction studies to interpret people's interactions with each other and/or devices. Advances in ubicomp technologies allow researchers to record spatial information through sensors in addition to video material. However, the volume of video data and high number of coding parameters involved in such an interaction analysis makes this a time-consuming and labour-intensive process. We designed EagleView, which provides analysts with real-time visualisations during playback of videos and an accompanying data-stream of tracked interactions. Real-time visualisations take into account key proxemic dimensions, such as distance and orientation. Overview visualisations show people's position and movement over longer periods of time. EagleView also allows the user to query people's interactions with an easy-to-use visual interface. Results are highlighted on the video player's timeline, enabling quick review of relevant instances. Our evaluation with expert users showed that EagleView is easy to learn and use, and the visualisations allow analysts to gain insights into collaborative activities

Weak instances of class group action based cryptography via self-pairings

In this paper we study non-trivial self-pairings with cyclic domains that are compatible with isogenies between elliptic curves oriented by an imaginary quadratic order $\mathcal{O}$. We prove that the order $m$ of such a self-pairing necessarily satisfies $m \mid \Delta_\mathcal{O}$ (and even $2m \mid \Delta_\mathcal{O}$ if $4 \mid \Delta_\mathcal{O}$ and $4m \mid \Delta_\mathcal{O}$ if $8 \mid \Delta_\mathcal{O}$) and is not a multiple of the field characteristic. Conversely, for each $m$ satisfying these necessary conditions, we construct a family of non-trivial cyclic self-pairings of order $m$ that are compatible with oriented isogenies, based on generalized Weil and Tate pairings. As an application, we identify weak instances of class group actions on elliptic curves assuming the degree of the secret isogeny is known. More in detail, we show that if $m^2 \mid \Delta_\mathcal{O}$ for some prime power $m$ then given two primitively $\mathcal{O}$-oriented elliptic curves $(E, \iota)$ and $(E\u27,\iota\u27) = [\mathfrak{a}] (E,\iota)$ connected by an unknown invertible ideal $\mathfrak{a} \subseteq \mathcal{O}$, we can recover $\mathfrak{a}$ essentially at the cost of a discrete logarithm computation in a group of order $m^2$, assuming the norm of $\mathfrak{a}$ is given and is smaller than $m^2$. We give concrete instances, involving ordinary elliptic curves over finite fields, where this turns into a polynomial time attack. Finally, we show that these self-pairings simplify known results on the decisional Diffie-Hellman problem for class group actions on oriented elliptic curves